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  Subjects -> CHEMISTRY (Total: 881 journals)
    - ANALYTICAL CHEMISTRY (54 journals)
    - CHEMISTRY (616 journals)
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CHEMISTRY (616 journals)                  1 2 3 4 | Last

Showing 1 - 200 of 735 Journals sorted alphabetically
2D Materials     Hybrid Journal   (Followers: 14)
Accreditation and Quality Assurance: Journal for Quality, Comparability and Reliability in Chemical Measurement     Hybrid Journal   (Followers: 26)
ACS Catalysis     Hybrid Journal   (Followers: 43)
ACS Chemical Neuroscience     Hybrid Journal   (Followers: 21)
ACS Combinatorial Science     Hybrid Journal   (Followers: 23)
ACS Macro Letters     Hybrid Journal   (Followers: 25)
ACS Medicinal Chemistry Letters     Hybrid Journal   (Followers: 41)
ACS Nano     Hybrid Journal   (Followers: 280)
ACS Photonics     Hybrid Journal   (Followers: 14)
ACS Symposium Series     Full-text available via subscription  
ACS Synthetic Biology     Hybrid Journal   (Followers: 24)
Acta Chemica Iasi     Open Access   (Followers: 5)
Acta Chimica Slovaca     Open Access   (Followers: 2)
Acta Chimica Slovenica     Open Access   (Followers: 1)
Acta Chromatographica     Full-text available via subscription   (Followers: 9)
Acta Facultatis Medicae Naissensis     Open Access  
Acta Metallurgica Sinica (English Letters)     Hybrid Journal   (Followers: 7)
Acta Scientifica Naturalis     Open Access   (Followers: 3)
adhäsion KLEBEN & DICHTEN     Hybrid Journal   (Followers: 7)
Adhesion Adhesives & Sealants     Hybrid Journal   (Followers: 9)
Adsorption Science & Technology     Open Access   (Followers: 6)
Advanced Functional Materials     Hybrid Journal   (Followers: 57)
Advanced Science Focus     Free   (Followers: 5)
Advances in Chemical Engineering and Science     Open Access   (Followers: 67)
Advances in Chemical Science     Open Access   (Followers: 18)
Advances in Chemistry     Open Access   (Followers: 21)
Advances in Colloid and Interface Science     Full-text available via subscription   (Followers: 19)
Advances in Drug Research     Full-text available via subscription   (Followers: 24)
Advances in Environmental Chemistry     Open Access   (Followers: 5)
Advances in Enzyme Research     Open Access   (Followers: 10)
Advances in Fluorine Science     Full-text available via subscription   (Followers: 9)
Advances in Fuel Cells     Full-text available via subscription   (Followers: 16)
Advances in Heterocyclic Chemistry     Full-text available via subscription   (Followers: 11)
Advances in Materials Physics and Chemistry     Open Access   (Followers: 25)
Advances in Nanoparticles     Open Access   (Followers: 15)
Advances in Organometallic Chemistry     Full-text available via subscription   (Followers: 16)
Advances in Polymer Science     Hybrid Journal   (Followers: 44)
Advances in Protein Chemistry     Full-text available via subscription   (Followers: 18)
Advances in Protein Chemistry and Structural Biology     Full-text available via subscription   (Followers: 20)
Advances in Quantum Chemistry     Full-text available via subscription   (Followers: 6)
Advances in Science and Technology     Full-text available via subscription   (Followers: 12)
African Journal of Bacteriology Research     Open Access  
African Journal of Chemical Education     Open Access   (Followers: 3)
African Journal of Pure and Applied Chemistry     Open Access   (Followers: 7)
Agrokémia és Talajtan     Full-text available via subscription   (Followers: 2)
Al-Kimia : Jurnal Penelitian Sains Kimia     Open Access  
Alkaloids: Chemical and Biological Perspectives     Full-text available via subscription   (Followers: 2)
AMB Express     Open Access   (Followers: 1)
Ambix     Hybrid Journal   (Followers: 3)
American Journal of Biochemistry and Biotechnology     Open Access   (Followers: 65)
American Journal of Biochemistry and Molecular Biology     Open Access   (Followers: 20)
American Journal of Chemistry     Open Access   (Followers: 30)
American Journal of Plant Physiology     Open Access   (Followers: 11)
American Mineralogist     Hybrid Journal   (Followers: 15)
Analyst     Full-text available via subscription   (Followers: 38)
Angewandte Chemie     Hybrid Journal   (Followers: 169)
Angewandte Chemie International Edition     Hybrid Journal   (Followers: 243)
Annals of Clinical Chemistry and Laboratory Medicine     Open Access   (Followers: 5)
Annual Reports in Computational Chemistry     Full-text available via subscription   (Followers: 3)
Annual Reports Section A (Inorganic Chemistry)     Full-text available via subscription   (Followers: 4)
Annual Reports Section B (Organic Chemistry)     Full-text available via subscription   (Followers: 9)
Annual Review of Chemical and Biomolecular Engineering     Full-text available via subscription   (Followers: 12)
Annual Review of Food Science and Technology     Full-text available via subscription   (Followers: 13)
Anti-Infective Agents     Hybrid Journal   (Followers: 3)
Antiviral Chemistry and Chemotherapy     Hybrid Journal   (Followers: 2)
Applied Organometallic Chemistry     Hybrid Journal   (Followers: 9)
Applied Spectroscopy     Full-text available via subscription   (Followers: 23)
Applied Surface Science     Hybrid Journal   (Followers: 32)
Arabian Journal of Chemistry     Open Access   (Followers: 6)
ARKIVOC     Open Access   (Followers: 1)
Asian Journal of Biochemistry     Open Access   (Followers: 2)
Atomization and Sprays     Full-text available via subscription   (Followers: 4)
Australian Journal of Chemistry     Hybrid Journal   (Followers: 7)
Autophagy     Hybrid Journal   (Followers: 2)
Avances en Quimica     Open Access  
Biochemical Pharmacology     Hybrid Journal   (Followers: 10)
Biochemistry     Hybrid Journal   (Followers: 355)
Biochemistry Insights     Open Access   (Followers: 6)
Biochemistry Research International     Open Access   (Followers: 6)
BioChip Journal     Hybrid Journal  
Bioinorganic Chemistry and Applications     Open Access   (Followers: 10)
Bioinspired Materials     Open Access   (Followers: 5)
Biointerface Research in Applied Chemistry     Open Access   (Followers: 2)
Biointerphases     Open Access   (Followers: 1)
Biology, Medicine, & Natural Product Chemistry     Open Access   (Followers: 2)
Biomacromolecules     Hybrid Journal   (Followers: 21)
Biomass Conversion and Biorefinery     Partially Free   (Followers: 10)
Biomedical Chromatography     Hybrid Journal   (Followers: 7)
Biomolecular NMR Assignments     Hybrid Journal   (Followers: 3)
BioNanoScience     Partially Free   (Followers: 5)
Bioorganic & Medicinal Chemistry     Hybrid Journal   (Followers: 132)
Bioorganic & Medicinal Chemistry Letters     Hybrid Journal   (Followers: 86)
Bioorganic Chemistry     Hybrid Journal   (Followers: 10)
Biopolymers     Hybrid Journal   (Followers: 18)
Biosensors     Open Access   (Followers: 2)
Biotechnic and Histochemistry     Hybrid Journal   (Followers: 2)
Bitácora Digital     Open Access  
Boletin de la Sociedad Chilena de Quimica     Open Access  
Bulletin of the Chemical Society of Ethiopia     Open Access   (Followers: 1)
Bulletin of the Chemical Society of Japan     Full-text available via subscription   (Followers: 24)
Bulletin of the Korean Chemical Society     Hybrid Journal   (Followers: 1)
C - Journal of Carbon Research     Open Access   (Followers: 3)
Cakra Kimia (Indonesian E-Journal of Applied Chemistry)     Open Access  
Canadian Association of Radiologists Journal     Full-text available via subscription   (Followers: 2)
Canadian Journal of Chemistry     Hybrid Journal   (Followers: 10)
Canadian Mineralogist     Full-text available via subscription   (Followers: 6)
Carbohydrate Research     Hybrid Journal   (Followers: 26)
Carbon     Hybrid Journal   (Followers: 70)
Catalysis for Sustainable Energy     Open Access   (Followers: 8)
Catalysis Reviews: Science and Engineering     Hybrid Journal   (Followers: 7)
Catalysis Science and Technology     Free   (Followers: 8)
Catalysis Surveys from Asia     Hybrid Journal   (Followers: 3)
Catalysts     Open Access   (Followers: 10)
Cellulose     Hybrid Journal   (Followers: 7)
Cereal Chemistry     Full-text available via subscription   (Followers: 4)
ChemBioEng Reviews     Full-text available via subscription   (Followers: 1)
ChemCatChem     Hybrid Journal   (Followers: 8)
Chemical and Engineering News     Free   (Followers: 19)
Chemical Bulletin of Kazakh National University     Open Access  
Chemical Communications     Full-text available via subscription   (Followers: 74)
Chemical Engineering Research and Design     Hybrid Journal   (Followers: 26)
Chemical Research in Chinese Universities     Hybrid Journal   (Followers: 3)
Chemical Research in Toxicology     Hybrid Journal   (Followers: 22)
Chemical Reviews     Hybrid Journal   (Followers: 190)
Chemical Science     Open Access   (Followers: 25)
Chemical Technology     Open Access   (Followers: 26)
Chemical Vapor Deposition     Hybrid Journal   (Followers: 5)
Chemie in Unserer Zeit     Hybrid Journal   (Followers: 56)
Chemie-Ingenieur-Technik (Cit)     Hybrid Journal   (Followers: 24)
ChemInform     Hybrid Journal   (Followers: 8)
Chemistry & Biodiversity     Hybrid Journal   (Followers: 7)
Chemistry & Biology     Full-text available via subscription   (Followers: 32)
Chemistry & Industry     Hybrid Journal   (Followers: 7)
Chemistry - A European Journal     Hybrid Journal   (Followers: 159)
Chemistry - An Asian Journal     Hybrid Journal   (Followers: 16)
Chemistry and Materials Research     Open Access   (Followers: 21)
Chemistry Central Journal     Open Access   (Followers: 4)
Chemistry Education Research and Practice     Free   (Followers: 5)
Chemistry in Education     Open Access   (Followers: 9)
Chemistry International     Open Access   (Followers: 2)
Chemistry Letters     Full-text available via subscription   (Followers: 43)
Chemistry of Materials     Hybrid Journal   (Followers: 256)
Chemistry of Natural Compounds     Hybrid Journal   (Followers: 9)
Chemistry World     Full-text available via subscription   (Followers: 19)
Chemistry-Didactics-Ecology-Metrology     Open Access   (Followers: 1)
ChemistryOpen     Open Access   (Followers: 1)
Chemkon - Chemie Konkret, Forum Fuer Unterricht Und Didaktik     Hybrid Journal  
Chemoecology     Hybrid Journal   (Followers: 4)
Chemometrics and Intelligent Laboratory Systems     Hybrid Journal   (Followers: 14)
Chemosensors     Open Access  
ChemPhysChem     Hybrid Journal   (Followers: 12)
ChemPlusChem     Hybrid Journal   (Followers: 2)
ChemTexts     Hybrid Journal  
CHIMIA International Journal for Chemistry     Full-text available via subscription   (Followers: 2)
Chinese Journal of Chemistry     Hybrid Journal   (Followers: 6)
Chinese Journal of Polymer Science     Hybrid Journal   (Followers: 11)
Chromatographia     Hybrid Journal   (Followers: 24)
Chromatography     Open Access   (Followers: 2)
Chromatography Research International     Open Access   (Followers: 6)
Clay Minerals     Full-text available via subscription   (Followers: 10)
Cogent Chemistry     Open Access   (Followers: 1)
Colloid and Interface Science Communications     Open Access  
Colloid and Polymer Science     Hybrid Journal   (Followers: 11)
Colloids and Interfaces     Open Access  
Colloids and Surfaces B: Biointerfaces     Hybrid Journal   (Followers: 6)
Combinatorial Chemistry & High Throughput Screening     Hybrid Journal   (Followers: 4)
Combustion Science and Technology     Hybrid Journal   (Followers: 22)
Comments on Inorganic Chemistry: A Journal of Critical Discussion of the Current Literature     Hybrid Journal   (Followers: 2)
Communications Chemistry     Open Access  
Composite Interfaces     Hybrid Journal   (Followers: 7)
Comprehensive Chemical Kinetics     Full-text available via subscription   (Followers: 1)
Comptes Rendus Chimie     Full-text available via subscription  
Comptes Rendus Physique     Full-text available via subscription   (Followers: 1)
Computational and Theoretical Chemistry     Hybrid Journal   (Followers: 9)
Computational Biology and Chemistry     Hybrid Journal   (Followers: 12)
Computational Chemistry     Open Access   (Followers: 2)
Computers & Chemical Engineering     Hybrid Journal   (Followers: 10)
Coordination Chemistry Reviews     Full-text available via subscription   (Followers: 4)
Copernican Letters     Open Access   (Followers: 1)
Corrosion Series     Full-text available via subscription   (Followers: 6)
Critical Reviews in Biochemistry and Molecular Biology     Hybrid Journal   (Followers: 6)
Croatica Chemica Acta     Open Access  
Crystal Structure Theory and Applications     Open Access   (Followers: 4)
CrystEngComm     Full-text available via subscription   (Followers: 13)
Current Catalysis     Hybrid Journal   (Followers: 2)
Current Chromatography     Hybrid Journal  
Current Green Chemistry     Hybrid Journal  
Current Metabolomics     Hybrid Journal   (Followers: 5)
Current Microwave Chemistry     Hybrid Journal  
Current Opinion in Colloid & Interface Science     Hybrid Journal   (Followers: 9)
Current Opinion in Molecular Therapeutics     Full-text available via subscription   (Followers: 14)
Current Research in Chemistry     Open Access   (Followers: 8)
Current Science     Open Access   (Followers: 69)
Current Trends in Biotechnology and Chemical Research     Open Access   (Followers: 3)
Dalton Transactions     Full-text available via subscription   (Followers: 23)
Detection     Open Access   (Followers: 2)
Developments in Geochemistry     Full-text available via subscription   (Followers: 2)
Diamond and Related Materials     Hybrid Journal   (Followers: 12)
Dislocations in Solids     Full-text available via subscription  
Doklady Chemistry     Hybrid Journal  

        1 2 3 4 | Last

Journal Cover
Arabian Journal of Chemistry
Journal Prestige (SJR): 0.591
Citation Impact (citeScore): 2
Number of Followers: 6  

  This is an Open Access Journal Open Access journal
ISSN (Print) 1878-5352
Published by Elsevier Homepage  [3159 journals]
  • Synergistic interface between Co3O4 and MgAl2O4 in CO2 assisted continuous
           

    • Abstract: Publication date: Available online 9 August 2018Source: Arabian Journal of ChemistryAuthor(s): Venkata Rao Madduluri, Peddinti Nagaiah, Challa Prathap, K. Vasikarappa, Ajmeera Nagu, Burri David Raju, Kamaraju Seetha Rama Rao A Series of Co3O4/MgAl2O4 spinel catalysts were prepared by conventional co-precipitation method with various Co loadings (0.5, 0.75, 1.0 and 1.25) keeping Mg/Al atomic ratio of 1.0 with over all Co+Mg+Al concentration at 3.0. Catalysts characteristics were throughly obtained by X ray diffraction (XRD), Fourier transform infra-red spectroscopy (FT-IR), UV-Vis Diffuse reflectance spectra, Temperature programmed reduction (H2-TPR), Transmission electron microscopy (TEM), Thermogravimetric analysis (TGA), NH3 and CO2 Temperture programmed desorption (TPD), CO2 pulse chemisorption, CHNS elemental analysis, and Surface area techniques. The superior catalytic activity accomplished by the catalyst with Co concentration of 1.0 (Co3O4/MgAl2O4), for an oxidative dehydrogenation of ethylbenzene can be ascribed to the presence of more number of active Co species. Co-precipitation method seems to be a excellent method in maintaining better synergistic influence, more number of active solid solution species such as MgCo2O4 or MgxCo(1-x)Al2O4 which were advantageous role for better catalytic efficiency. Suitable number of optimized acidic-basic properties measured by NH3 and CO2-TPD analysis was another property influencing the activity with respect to desired product contribution. Higher, 81.2% ethylbenzene conversion (81.2%) with 98% styrene selectivity was attained on 1.0Co3O4/MgAl2O4 in comparision to Co3O4/MgO, and Co3O4/γ-Al2O3 catalysts. According to the CO2 pulse chemisorption reaction with dehydrogenation of ethylbenzene over 1.0Co3O4/MgAl2O4 resulted to get superior CO yield which was promised to get higher ethylbenzene conversion as well as styrene selectivity.Graphical abstractCMA catalysts afforded superior EB conversion and ST selectivity comapared to repotrted cobalt based and other solid oxide catalysts.Graphical abstract for this article
       
  • Amorphous content on the photocatalytic performance of micrometer-sized
           tungsten trioxide particles

    • Abstract: Publication date: Available online 7 August 2018Source: Arabian Journal of ChemistryAuthor(s): Asep Bayu Dani Nandiyanto, Rosi Oktiani, Risti Ragadhita, Ajeng Sukmafitri, Rena Zaen The purpose of this study was to investigate the correlation between amorphous content and the characteristics of micrometer-sized photocatalyst particles. As a model of photocatalyst, tungsten trioxide (WO3) particles with controllable amorphous contents were used. To comprehend the amorphous content parameter precisely, the experiments were conducted by heating amorphous WO3 powders at a specific temperature without additional chemicals or solvents. Thus, the percentage of amorphous in the WO3 particles was controlled independently in the constant particle outer sizes and morphology. Micrometer-sized catalyst was used to avoid the misleading photocatalytic measurements due to the over-dominancy of other catalytic parameters (such as excessive surface area and quantum confinement effect). The results revealed that in the constant process condition, the photocatalytic properties were strongly dependent on the amorphous content in the catalyst. Decreases in this parameter had a strong influence to the enhancement of the photodecomposition rate of organic material. The tendency for the influence of amorphous content was also confirmed by varying the number of catalysts in the photocatalytic process. The study was also completed with the theoretical consideration for the phenomenon happening during the WO3 crystallization (transformation of amorphous into hexagonal and monoclinic crystal structure) and the photocatalytic process.
       
  • Functionalized electrospun carbon nanofibers for removal of cationic dye

    • Abstract: Publication date: Available online 4 August 2018Source: Arabian Journal of ChemistryAuthor(s): Badr M. Thamer, Hany El-Hamshary, Salem S. Al-Deyab, Mohamed H. El-Newehy Electrospun carbon nanofibers (ECNFs) have attracted significant attention in recent years as relatively inexpensive alternative to carbon nanotubes for adsorption organic pollutants. In this study, ECNFs were fabricated from polyacrylonitrile (PAN) using an electrospinning technique, followed by carbonization and oxidation via treatment with a H2SO4/HNO3 mixture. The prepared oxidized electrospun carbon nanofibers (O-ECNFs) were characterized using scanning and transmission electron microscopy (SEM and TEM), Fourier transform infrared (FT-IR), Brunauer-Emmett-Teller (BET), X-ray diffraction (XRD), and thermogravimetric analysis (TGA). The O-ECNFs were used as nano-adsorbents for the adsorption of methylene blue (MB) from aqueous solution. The adsorption of MB by the O-ECNFs was studied as a function of pH, time, adsorbent dosage, MB concentration, and temperature. ECNF functionalization enhanced the adsorption capacity towards MB dye compared pristine ECNFs. Detailed analysis of the adsorption kinetics showed that the adsorption process followed a pseudo-second-order model. The adsorption isotherm was best fit by the Langmuir model. The thermodynamic results showed that MB adsorption onto the O-ECNFs was endothermic and spontaneous.Graphical abstractGraphical abstract for this article
       
  • Quantitative screening of parabens in Ready-to-eat foodstuffs available in
           the Saudi market using high performance liquid chromatography with
           photodiode array detection

    • Abstract: Publication date: Available online 2 August 2018Source: Arabian Journal of ChemistryAuthor(s): Hadir M. Maher, Nourah Z. Alzoman, Munira Abdulaziz Almeshal, Hawazin Abdullah Alotaibi, Njoud Naif Alotaibi, Hessa Al-Showiman Parabens are widely used as preservatives in thousands of consumer’s products including, cosmetics, pharmaceutical products, and foodstuffs. Concern in regards to the safety of parabens has been raised where parabens have been classified as “Endocrine distributing compounds” with potential link to many tumor types. Despite their wide spread, the occurrence of parabens in foodstuffs available in the Saudi market has not been studied until now. In this work, an HPLC-PDA method was developed and validated for the screening of parabens’ residues in different categories of Ready-to-eat foodstuffs collected from the Saudi market. These categories include: cereals, meat, fish, dairy product, bean products, fruits, vegetables, cookies and snacks, beverages, condiments, and others. Chromatographic analysis of the selected parabens (Methyl paraben MeP ,ethyl paraben EtP, propyl paraben PrP, butyl paraben BuP, and isobutyl paraben isoBuP) was performed on Symmetry® C-18 Colum (4.6×75mm,3.5μm) with methanol/water (57:43,v/v) as the mobile phase and using simply methanol for sample preparation . The proposed method was fully validated with regards to linearity, limits of detection (LOD) and of quantification (LOQ), accuracy and precision, extraction recovery, and specificity. Matrix-based calibration curves were linear in the range 0.025-500 μg/g (MeP, EtP), 0.05-500 μg/g (PrP), and 0.125-1250 μg/g (IsoBuP, BuP) with LOQ 0.025 μg/g for MeP, EtP, 0.05 μg/g for PrP, 0.125 μg/g for both BuP and isoBuP. The method was successfully applied for quantitative screening of the five parabens in different Ready-to-eat foodstuffs (n=215) collected from the Saudi market. The total parabens content was determined and was related to the food category and to the packaging material. The highest paraben content was found in cereals and condiments. The type of the packaging material did not have a significant effect on the paraben content among all food categories. Moreover, the estimated daily intake of parabens among the Saudi adults was calculated and it was found to have an average of 2000 μg/kgbw/day.
       
  • Preparation of nanoparticulate TiO2 containing nanocrystalline phases of
           Anatase and Brookite by electrochemical dissolution of remelted Titanium
           Components

    • Abstract: Publication date: Available online 29 July 2018Source: Arabian Journal of ChemistryAuthor(s): D. Ortega-Díaz, D. Fernández, S. Sepúlveda, R.R. Lindeke, J.J. Pérez-Bueno, E. Peláez-Abellán, J. Manríquez In this investigation, we present an efficient electrochemical methodology to prepare nano-particulate TiO2 having a nano-crystalline composition of 40% Anatase and 60% Brookite, without need for subsequent thermal treatments (which are typically applied to alter the amount of amorphicity). This procedure for oxide synthesis is novel as it involves the galvanostatic dissolution of remelted Titanium Components, thus constituting a promising technological route for re-using Titanium-containing metallic pieces from the secondary metals industry to produce nano-crystalline TiO2 powders as a high value-added primary product. The experimental results presented showed that the faradaic efficiency of the TiO2 electro-synthesis, crystalline purity, and dispersion of the electro-generated TiO2 material was significant, despite the fact that the titanium content of the remelted titanium components was less than 80%.Graphical abstractGraphical abstract for this article
       
  • Tuning the morphological structure, light absorption, and photocatalytic
           activity of Bi2WO6 and Bi2WO6-BiOCl through cerium doping

    • Abstract: Publication date: Available online 29 July 2018Source: Arabian Journal of ChemistryAuthor(s): Mirabbos Hojamberdiev, Zuhra Kadirova, Ehsan Zahedi, Diego Onna, María Claudia Marchi, Gangqiang Zhu, Nobuhiro Matsushita, Masashi Hasegawa, Sara Aldabe Bilmes, Kiyoshi Okada Pharmaceuticals and personal care products are recognized as new classes of water pollutants that receive considerable attention because of their negative environmental impact on aquatic life and humans. Because microbiological and/or conventional secondary physicochemical treatments cannot completely remove those water pollutants, effective advanced oxidation processes using semiconductor-based photocatalysts are needed to ensure their total elimination in water. Here, we report on the tuning of the morphological structure, light absorption, and photocatalytic activity of Bi2WO6 and Bi2WO6-BiOCl through cerium doping. Non-doped and Ce-doped Bi2WO6 and Bi2WO6-BiOCl powders are synthesized by a hydrothermal method, and their adsorption ability and photocatalytic activity are evaluated for the removal of salicylic acid in the dark and under visible light irradiation, respectively. The adsorption affinities and preferential sites of salicylic acid molecules on non-doped and Ce-doped Bi2WO6, BiOCl, and Bi2WO6-BiOCl are computationally predicted using molecular dynamics simulations. When ethylene glycol is replaced by dilute HCl as a solvent in a hydrothermal system, BiOCl is also formed along with Bi2WO6, confirming the successful formation of a Bi2WO6-BiOCl composite. The flower-like hierarchical structures of Bi2WO6 and Bi2WO6-BiOCl can absorb more photon energy due to multiple scattering, charge carriers can easily transfer to the surface/interface, and mesopores can improve the transfer rate of organic molecules, contributing to the overall enhancement in photocatalytic activity. The Bi2WO6-BiOCl samples show higher photocatalytic activity than that of the Bi2WO6 samples for the degradation of salicylic acid due to the formed p–n heterojunction. The optimum concentration of Ce doping is found to be 1 mol% in the Bi2WO6 and Bi2WO6-BiOCl, promoting the effective separation and transfer of photogenerated charge carriers, resulting in high photocatalytic performance, and the sample exhibited good stability.Graphical abstractGraphical abstract for this article
       
  • Comparative studies of sunlight mediated green synthesis of silver
           nanoparaticles from Azadirachta indica leaf extract and its antibacterial
           effect on Xanthomonas oryzae pv oryzae

    • Abstract: Publication date: Available online 29 July 2018Source: Arabian Journal of ChemistryAuthor(s): Mounil Mankad, Ghanshyam Patil, Dimpy Patel, Parthvi Patel, Armi Patel Biogenic synthesis of silver nanoparticle (AgNPs) has attracted worldwide attention as it is cheap and non-toxic. Therefore, in present study sunlight mediated silver nanoparticle was synthesized from Azadirachta indica A. Juss (Neem) leaf extract. Various combinations i.e., reducing agent (5, 10, 15 and 20 ml leaf extract), substrate concentration (1mM AgNO3) and sunlight durations (5, 10, 15 and 20 minutes) were assessed for their ability to synthesized stabilized AgNPs. Leaf extract provide both reducing and capping agent, while sunlight served as catalyst for the synthesis process. The green synthesized AgNPs were characterized using change in color due to Surface Plasmon Resonance further analyzed by UV-visible spectroscopy, dynamic light scattering for size, polydispersity index and zeta potential for stability studies and Fourier Transform Infrared Spectroscopy (FT-IR). The smallest size of synthesized AgNPs was 67.94±0.72 nm synthesized using to 20ml of reducing agent (leaf extract) and 5 minute of sunlight exposure. Antibacterial activity of synthesized silver nanoparticle was examined against plant pathogen Xanthomonas oryzae pv. oryzae (Xoo) and showed a good antimicrobial activity compared to 200 mg/l of streptocycline.
       
  • Mesoporous cobalt phosphate electrocatalyst prepared using liquid crystal
           template for methanol oxidation reaction in alkaline solution

    • Abstract: Publication date: Available online 29 July 2018Source: Arabian Journal of ChemistryAuthor(s): Merfat S. Al-Sharif, Prabhakarn Arunachalam, Twaha Abiti, Mabrook S. Amer, Matar Al-Shalwi, Mohamed A. Ghanem A crystalline mesoporous cobalt phosphate (meso-CoPi) electrocatalyst is prepared using liquid crystal template of non-ionic surfactant of Brij®78. The physicochemical investigations of the electrocatalyst executed by surface area analyzer, XRD, transmission electron microscope submits creation of a mesoporous crystalline nanostructured of meso-CoPi with a surface area of 124 m2g-1. This is an 10-fold greatness superior than that for bulk-CoPi particles produced without surfactant template. The meso-CoPi electrocatalyst comprises of metallic cobalt layered with a cobalt-oxo/hydroxo-phosphate layer which facilitates the electro-oxidation of methanol at modest overpotential of < 1.2 V vs RHE in alkaline solution. The methanol oxidation activity of the meso-CoPi catalyst shows more than 20-fold current increase at 1.4 VRHE in comparison to bulk-CoPi counterpart which due to the enhancement of the electroactive specific surface area. Liquid crystal template chemical approach provides a reproducible stage to synthesize mesoporous metal phosphates with improved electrocatalytic activities.
       
  • Acylhydrazidate-based porous coordination polymers and reversible I2
           adsorption properties

    • Abstract: Publication date: Available online 25 July 2018Source: Arabian Journal of ChemistryAuthor(s): Yan-Ning Wang, Rong-Yan Wang, Qing-Feng Yang, Jie-Hui Yu By employing the hydrothermal in situ acylation of organic acids with N2H4, three porous acylhydrazidate-based Zn2+/Cd2+ coordination polymers as [M(L1)(H2O)]·1.5H2O (H2L1 = benzimidazole-5,6-dihydrazide; M2+ = Zn2+1, Cd2+2) and [Zn(HL2)(H2O)]·3H2O (H3L2 = 4,5-(di-(3′,4′-phthalhydrazide))) 3 were obtained. X-ray single-crystal diffraction analysis reveals that the frameworks of 1–3 can all be simplified into a (3metal node,3ligand node)-connected net. However, since the ligands are different, they show the distinct structures: a C-tube-like structure for the isostructural 1 and 2; a 103 topology for 3. The cif-checking reports indicate that the solvent accessible voids in the structures of 1–3 are 1055 Å3, 1282.4 Å3, and 978 Å3, respectively. It is noteworthy that 3 is the first example of triacylhydrazidate-based coordination polymer. The investigation of the I2-adsorption property for two Zn2+ compounds suggests that both can adsorb reversibly the I2 molecule. The adsorption amount for 3 (100 mg adsorbing 22.0 mg I2) is a bit higher than that for 1 (100 mg accommodating 15.6 mg I2). However, the adsorption speed for 3 is much faster than that for 1. About 5 s, the I2 adsorption for 3 is close to saturation, while for 1, it is about 20 days. This might be related to the number and the distribution for the uncoordinated N/O atoms on the side walls of the channels.Graphical abstractStructures of three acylhydrazidate-based porous coordination polymers were reported, reversible I2 adsorption properties were investigated, and factors of influencing adsorption property were discussed.Graphical abstract for this article
       
  • Economical, environmental friendly synthesis, characterization for the
           production of zeolitic imidazolate framework-8 (ZIF-8) nanoparticles with
           enhanced CO2 adsorption

    • Abstract: Publication date: Available online 23 July 2018Source: Arabian Journal of ChemistryAuthor(s): Imran Ullah Khan, Mohd Hafiz Dzarfan Othman, Asim Jilani, A.F. Ismail, Haslenda Hashim, Juhana Jaafar, Mukhlis A. Rahman, Ghani Ur Rehman Zeolitic imidazole framework 8 (ZIF-8) nanoparticles were successfully synthesized in an aqueous solution at the ambient condition with a relatively low molar ratio of zinc salt and an organic ligand, Zn+2/Hmim (1: 8). ZIF-8 has remarkable thermal and chemical stability, tunable microporous structure, and a great potential for absorption, adsorption, and separation. Various physicochemical characterization techniques like X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), attenuated total reflected infrared spectroscopy (ATR-IR), thermogravimetric analysis (TGA), and surface area with pore textural properties by micromeritics gas adsorption equipment were performed to investigate the effect of base type additive triethylamine (TEA) on the morphology, crystallinity, yield, particle and crystal size, thermal stability and microporosity of ZIF-8 nanoparticles. The total quantity of basic sites and carbon dioxide (CO2) desorption aptitude was also calculated using CO2 temperature-programmed desorption (CO2-TPD) system. The pure ZIF-8 nanoparticles of 177 nm were formed at TEA/total mole ratio of 0.002. Furthermore, the size of ZIF-8 nanoparticles was decreased to 77 nm with increasing TEA/total mole ratio up to 0.004. The structures, particle sizes and textural properties of ammonia modified ZIF-8 particle can easily be tailored by the amount of aqueous ammonium hydroxide solution. The smallest ZIF-8 nanoparticles obtained were 75 nm after ammonia modification which shows excellent thermal stability and improved microporosity. The ZIF-8 basicity and uptakes of CO2 improved with TEA and ammonia modification which followed the order: A25ml–Z4> Z4> Z3> Z5> Z2> A50ml–Z4. The proposed economical and efficient synthesis method has great potential for large-scale production of ZIF-8.
       
  • Investigation on the g-C3N4 encapsulated ZnO nanorods heterojunction
           coupled with GO for effective photocatalytic activity under visible light
           irradiation

    • Abstract: Publication date: Available online 21 July 2018Source: Arabian Journal of ChemistryAuthor(s): N. Kumaresan, M. Maria Angelin Sinthiya, M. Praveen Kumar, S. Ravichandran, R. Ramesh Babu, K. Sethurman, K. Ramamurthi The present work reports on a novel ternary nanocomposite of ZnO rods encapsulated by graphitic like carbon nitride (g-C3N4) and coupled with graphene oxide (GO) prepared by ultrasonication assisted hydrothermal method which provides enhanced photocatalytic activity and stability. Field emission scanning electron microscopy analysis showed that the surface morphology of ZnO, g-C3N4 (prepared by heating method) and the GO contains nanorods structures, sheet like structures and sheets with porous structures respectively. Formation of rod like structures of ZnO and thin sheet like structures of g-C3N4 were observed from transmission electron microscopy analysis. Transmission electron microscopy analysis of g-C3N4 (6 wt.%)/ZnO nanocomposites showed that ZnO nanorods are encapsulated by the thin sheets of g-C3N4 and g-C3N4(6 wt.%)/ZnO/GO (30 mg) ternary nanocomposites contains porous structures of GO. The optical band gap of ZnO nanoparticles was shifted from 3.08 eV to 2.85 eV for g-C3N4(6 wt.%)/ZnO/GO(30 mg) ternary nanocomposites. Under visible light irradiation the ZnO nanorods and g-C3N4 (6 wt.%)/ZnO showed photodegradation efficiency of ∼21% and 90% respectively for 120 min whereas g-C3N4 (6 wt.%)/ZnO/GO(30 mg) showed about 99% photodegradation efficiency in a time period of 14 min. The recycle process carried out for g-C3N4(6 wt.%)/ZnO/GO(30 mg) composites up to five cycles showed 91.5% of photodegradation in the fifth cycle for a time period of 14 min. Total Organic Carbon (TOC) analysis shows removal of carbon content 83% of carbon content in 28 min. The Gas Chromatography-Mass Spectroscopy analysis shows the intermediate products of 1,2 benzenedicarboxylic acid and phthalic acid during the RhB dye photodegradation process. The radical trapping experiment reveals that the photo-induced holes (h+) are one of the main reactive species involved in the degradation of the RhB.
       
  • β -Ag2MoO4+microcrystals:+correlation+between+experimental+and+theoretical+data&rft.title=Arabian+Journal+of+Chemistry&rft.issn=1878-5352&rft.date=&rft.volume=">Hydrothermal synthesis, structural characterization and photocatalytic
           properties of β -Ag2MoO4 microcrystals: correlation between experimental
           and theoretical data

    • Abstract: Publication date: Available online 20 July 2018Source: Arabian Journal of ChemistryAuthor(s): Giancarlo da Silva Sousa, Francisco Xavier Nobre, Edgar Alves Araújo Júnior, Julio Ricardo Sambrano, Anderson dos Reis Albuquerque, Rosane dos Santos Bindá, Paulo Rogério da Costa Couceiro, Walter Ricardo Brito, Laécio Santos Cavalcante, Maria Rita de Morais Chaves Santos, José Milton Elias de Matos In this paper, we report about hydrothermal synthesis, structural characterization and photocatalytic properties of beta-silver molybdate (β-Ag2MoO4) microcrystals obtained at different temperatures (100, 120, 140 and 160 °C) for 2h. These crystals were characterized structurally using X−ray diffraction (XRD), X-ray fluorescence, Rietveld refinement, micro−Raman (m−Raman) and Fourier-transform infrared (FT-IR) spectroscopies. Experimental and theoretical band gap values were correlated by ultraviolet−visible (UV−Vis) diffuse reflectance spectroscopy and periodic first-principles calculations in the framework of density functional theory (DFT) with the B3LYP-D3 hybrid functional. The crystals morphology was observed through field-emission scanning electron microscopy (FE-SEM) images. The photocatalytic properties of these crystals were investigated for degradation of rhodamine B (RhB) dye under UV−light. XRD patterns and Rietveld refinement data indicate that all crystals exhibit a spinel-type cubic structure with space group (Fd3_m) formed by tetrahedral [MoO4] clusters and distorted octahedral [AgO6] clusters. m−Raman spectra exhibited five Raman-active modes in a range from 50 to 1,000 cm-1, while FT-IR spectra have three infrared active modes in a range from 400 to 1,100 cm-1. The experimental results from Raman and IR modes are in reasonable agreement with theoretically calculated results. Experimental UV−Vis spectra indicate a decrease in optical band gap (Egap = 3.35 eV to 3.32 eV) with the temperature rise. The calculated band structure revealed an indirect optical band gap (Egap) of approximately 3.94 eV. Moreover, theoretical calculations based on density of states and electron density maps were employed to understand the polarization phenomenon induced by structural defects in the β-Ag2MoO4 microcrystals. FE-SEM images revealed that the increase of processing temperatures promotes a change in shape of microcrystals from potatoes-like to coral-like. Finally, photocatalytic measures to degradation of the RhB dye resulted in the best catalytic performance for β-Ag2MoO4 microcrystals synthesized at temperatures of 120 and 140 °C, corresponding to 97.3% and 96.8% in the photodegradation of RhB dye under UV–light up to 2h. The stability of the β-Ag2MoO4 was investigated by reusing, resulting in f 97.2, 93.9 and 78.8% degradation of the RhB dye for the first, second and third cycle, respectively.
       
  • Synthesis of low-molecular-weight poly-α-olefins using silicon-bridged
           zirconocene catalyst for lubricant basestock

    • Abstract: Publication date: Available online 20 July 2018Source: Arabian Journal of ChemistryAuthor(s): Huaiqi Shao, Ruofei Wang, Hui Li, Xiaoyan Guo, Tao Jiang The oily oligomers with low-molecular-weight, medium kinematic viscosity and high viscosity index are yielded through oligomerizations of higher α-olefins (1-hexene, 1-octene, 1-decene, 1-dodecene and 1-tetradecene) and co-oligomerization of 1-decene with 1-butene in the presence of the silicon-bridged Ph2Si(Cp)(9-Flu)ZrCl2 catalyst and the methylaluminoxane co-catalyst. The oligomerization activity is affected by the bulkiness and lateral size of monomer, and the viscosity of oligomer obtained. Through adding of 1-butene to 1-decene, the oligomerization activity is decreased, but viscosity index of oligomer obviously is increased. The highest co-oligomerization activity of 1-decene with 1-butene is presented at the temperature of 60 °C and Al/Zr molar ratio of 300. 1H and 13C NMR spectroscopy reveal that four types of vinylidene are existed in oligomers and the major olefinic bonds are internal disubstituted vinylidene, which are produced through 2,1-misinsertion and β-hydride elimination, or 2,1-misinsertion and rearrangement followed by β-hydride elimination. The chain termination of oligomerization of α-olefins favors chain transfer to the co-catalyst to produce saturated end group. The oligomerization pathways are summarized.
       
  • Cordierite honeycomb monoliths coated with Al(III)/ZrO2 as an efficient
           

    • Abstract: Publication date: Available online 20 July 2018Source: Arabian Journal of ChemistryAuthor(s): S.R. Pratap, S.Z.M. Shamshuddin, N. Thimmaraju, M. Shyamsundar Al(III)/ZrO2 with 5–25 wt% Al(III) was coated on honeycomb monoliths by dip & dry technique and were also prepared in their powder forms for the purpose of comparison. These prepared catalysts were characterized for their total acidity, crystallinity, and morphology. The catalytic activity of Al(III)/ZrO2 was examined in 3 different modes of heating, i.e., conventional, ultrasonic, and microwave. The effect of calcination temperature of the catalyst, poisoning of acid sites of the catalyst by adsorbing pyridine adsorption on the physico-chemical properties and the catalytic activity was also studied. The results indicated that the microwave heating mode shows highest catalytic activity when compared to either ultrasonic or conventional modes. The honeycomb form of the catalysts shows almost 1.2 fold time increase in their catalytic activity when compared to their powder forms. Pre-adsorption studies disclose that the Knoevenagel condensation reaction obeys the Langmuir-Hinshelwood type which involves chemisorptions of both of the reactants. A faster kinetic study confirms that monolithic catalysts [15Z-A (CHM)] possess the least energy of activation (35.6 kJ/mol) while their powder forms analogs [15Z-A (PFM)] posses highest activation energy (59.2 kJ/mol) correspondingly with a shorter reaction time indicating that monolithic catalysts are highly efficient compared to their powder forms. Reusability tests pertaining to both calcined and uncalcined catalysts authenticates that calcination enhances catalytic activity with the augmentation of catalytically active sites.
       
  • Degradability and Biocompatibility of Magnesium-MAO: the Consistency and
           Contradiction Between in-vitro and in-vivo Outcomes

    • Abstract: Publication date: Available online 20 July 2018Source: Arabian Journal of ChemistryAuthor(s): Haitao Xu, Tu Hu, Manle Wang, Yuxin Zheng, Hui Qin, Huiliang Cao, Zhiquan An Magnesium-based metals are promising for biomedical use for its biodegradation characteristic. However, its rapid degradation in physiological environment impedes its application. Oxides coating is a widely-used form of surface modification to improve the corrosion resistance of biomaterials. In this study, we systematically compared two oxides coatings, steam oxidation (SO) and micro-arc oxidation (MAO), in controlling degradation and improving the biocompatibility of pure magnesium in vitro and in vivo. The addition of both coatings was found to reduce the degradation rate of magnesium in vitro at the early stage, but the corrosion behavior became severe with longer immersion time in all the groups. Unfortunately, all the coated and uncoated materials were found undermining the adhesion and proliferation of MC3T3-E1 cells in vitro, even at the first day of culture. In terms of in-vivo circumstance, the Mg-MAO group showed satisfying biocompatibility compared with pure Mg and Mg-SO, as is evidenced by radiographic results and histological analysis. Little corrosion was found, and more newly formed bone was observed in the animal model. These data suggest that the characteristic of in-vivo circumstance have considerable impacts on the degradation and bone integration process.
       
  • Fabrication of virus metal hybrid nanomaterials: An ideal reference for
           bio semiconductor

    • Abstract: Publication date: Available online 20 July 2018Source: Arabian Journal of ChemistryAuthor(s): Raja Muthuramalingam Thangavelu, Rajendran Ganapathy, Pandian Ramasamy, Kathiravan Krishnan Recently, Nanotechnology has made easier utilizing plant pathogens as a potential nanomaterial in biomedical applications. In this research work, we have exploited a devastating plant pathogenic virus of Squash leaf curl China virus (SLCCNV), as a nano-bio template (32 nm) to fabricate the gold and silver nanomaterials. This is achieved through the direct exposure of SLCCNV to gold chloride (HAuCll4) and silver nitrate (AgNO3) precursors at sunlight, resulted into SLCCNV-metallic-hybrid nanomaterials which are synthesized quick (∼5 min) and eco-friendly. However, virus hybrid nanomaterials are fabricated through the nucleation and growth of metal precursors over the pH-activated capsid of SLCCNV. Under the controlled fabrication process, it produced a highly arrayed virus-metallic-hybrid nanomaterial at nanoscale size limit. Its properties are thoroughly studied through spectroscopic techniques (UV–Vis, DLS, Raman) and electron microscopy (HRTEM & FESEM). In a follow-up study of cytotoxicity assay, the virus and its fabricated nanomaterials show better biocompatibility features even at high concentrations. Finally, the electrical conductivities of virus-metallic-hybrid nanomaterials (Au & Ag) are determined by simple “lab on a chip” system and Keithley's pico-ammeter. The result of electrical conductivity measurement revealed that hybrid nanomaterials have greater electrical conductive properties within the band-gap of semi-conductive materials. It is truly remarkable that a plant virus associated metal nanomaterials can be efficiently used as bio-semi-conductors which are the ideal one for biomedical applications.Graphical abstractGraphical abstract for this article
       
  • Physiochemical properties of TiO2 nanoparticle loaded APTES-functionalized
           MWCNTs composites and their photocatalytic activity with kinetic study

    • Abstract: Publication date: Available online 19 July 2018Source: Arabian Journal of ChemistryAuthor(s): Amirah Ahmad, Mohd Hasmizam Razali, Mazidah Mamat, Karimah Kassim, Khairul Anuar Mat Amin In this study, functionalized-MWCNTs with 3-aminopropyltriethoxysilane (APTES) loaded titania nanoparticles (MWCNTs-APTES-TiO2) were prepared to investigate their physicochemical properties and photocatalytic activity for methyl orange (MO) degradation. The TiO2 nanoparticles, functionalized-MNCNT and composite powders were characterized by XRD, raman, and TEM. The results obtained proved that titania (TiO2) nanoparticles was successfully loaded on APTES-MWCNTs. For application, MWCNTs-APTES-TiO2 composites were used as photocatalyst for degradation of methyl orange (MO) in aqueous solution under UV light irradiation and the result shows that 87% MO was degraded after 180 min. Kinetic analysis indicated that photocatalytic degradation of MO solution by MWCNTs-APTES-TiO2 obeyed second-order kinetic model (R2> 0.95), supported by half-life equations and graph. Because of the presence of carbon nanotubes accelerated the degradation of methyl orange due to inhibition of electron-hole recombination, the formation of additional hydroxyl radicals and functional groups of the latter had an inhibitory effect on the degradation of methyl orange. This study suggested the MWCNTs-APTES-TiO2 nanocomposite has considerable potential as environmental photocatalyst due to higher degradation rate as compared to bare TiO2.
       
  • Determination of carbamates in soils by liquid chromatography coupled with
           on-line postcolumn UV irradiation and chemiluminescence detection

    • Abstract: Publication date: Available online 18 July 2018Source: Arabian Journal of ChemistryAuthor(s): José A. Murillo Pulgarín, Luisa F. García Bermejo, Armando Carrasquero Durán In this study, high performance liquid chromatography (HPLC) coupled with a simple and fast sample pre-treatment based on the use of the UV-irradiation in a simple continuous flow system for the chemiluminescent quantification of pesticide carbamates in soils was developed and validated. HPLC was used to separate thiodicarb, bendiocarb and carbaryl in soil extracts. The eluates emerging from the column tail were mixed with an alkaline solution of Co2+ in EDTA and irradiated with UV light to induce photolysis of the carbamates, in order to obtain free radicals and other reactive species capable of oxidizing luminol and producing photoinduced chemiluminescence (PICL) as a result. Measurements of CL intensity were plotted as a function of time to obtain chromatographic peaks. Under the optimum operating conditions for the combined HPLC-PICL system, CL peak areas were linearly related to analyte concentrations. The limit of detection were 0.05 mg L-1 for thiodicarb, 0.09 mg L-1 for bendiocarb and 0.17 mg L-1 for carbaryl. A simple extraction procedure using 98% methanol as solvent ensured complete dissolution of the analytes in spiked soils with recoveries from 87 to 120 %. The proposed method is a simple, fast, accurate choice for quantifying the target pesticides in soils.
       
  • Sodium hyroxyethylcellulose adipate: An efficient and reusable sorbent for
           cadmium uptake from spiked high-hardness ground water

    • Abstract: Publication date: Available online 17 July 2018Source: Arabian Journal of ChemistryAuthor(s): Muhammad Ajaz Hussain, Shahana Zaman, Azhar Abbas, Muhammad Nawaz Tahir, Muhammad Amin, Syed Zajif Hussain, Irshad Hussain Herein, we report on the evaluation of chemically modified hyrdroxyethylcellulose for its sorption efficacy to uptake Cd(II) from spiked high-hardness ground water (GW) and aqueous solution (DW). Hyrdroxyethylcellulose was chemically modified using adipic anhydride in the presence of DMAP as a catalyst under homogeneous reaction conditions. Hyrdroxyethylcellulose adipate (HEC-Adip) obtained was then converted to its sodium salt as HEC-Adip-Na after treating with NaHCO3. Structures were thoroughly characterized using FTIR, SEM, EDS and solid-state CP/MAS 13C NMR. The surface charge and morphology of the sorbent was determined using pHZPC (pH of zero point charge). The sorption data fitted well to Langmuir isotherm and pseudo-second order kinetic model. Maximum sorption capacity of Cd(II) was calculated to be 114.94 mg g–1 and 112.35 mg g-1 from DW and GW, respectively. Thermodynamic parameters, i.e., ΔH°, ΔS° and ΔG°, were also calculated and showed negative values indicating spontaneous and exothermic nature of sorption process. In addition, the synthesized sorbent is more suitable for repeated use because it shows negligible decrease in its sorption capacity for the uptake of Cd(II) from aqueous solution after five regeneration cycles.
       
  • Unlocking the Synthetic Potential of Aziridine and Cyclopropane-Fused
           Quinolin-2-ones by Regioselective Fragmentation of its Three-membered
           Rings

    • Abstract: Publication date: Available online 11 July 2018Source: Arabian Journal of ChemistryAuthor(s): Javier Diaz, Daniel Rodenas, Francisco-Jose Ballester, Mateo Alajarin, Raul-Angel Orenes, Pilar Sanchez-Andrada, Angel Vidal The cyclization of cis-2-(2-azidophenyl)-1-benzyl-3-ethoxycarbonylaziridines and trans-2-(2-azidophenyl)-3-nitrocyclopropane-1,1-dicarboxylates yielded the respective aziridino[2,3-c]quinolin-2-ones and cyclopropa[c]quinolin-2-ones. Ring-opening of the aziridine-fused species under silica gel catalysis provided 3-aminoquinolin-2-ones whereas the ring-expansion of the cyclopropane-fused derivatives by the action of sodium hydride gave 1-benzazepin-2-ones, in both cases in a regioselective manner. A computational study using DFT methods revealed that the mechanism for the transformation of cyclopropa[c]quinolin-2-ones into 1-benzazepin-2-ones involves the initial deprotonation step of its amide function followed by two pericyclic events: a 6π-electrocyclic ring opening and a subsequent [1,5]-H shift.Graphical abstractAziridine- and cyclopropa-fused quinolones, obtained by annulation of the quinoline core to substituted aziridines and cyclopropanes, undergo regioselective ring-fragmentation of the three membered ring to afford 3-aminoquinolin-2-ones and 1-benzazepin-2-ones.Graphical abstract for this article
       
  • Synthesis and characterization of surface-active antimicrobial
           hyperbranched polyurethane coatings based on oleo-ethers of boric acid

    • Abstract: Publication date: Available online 10 July 2018Source: Arabian Journal of ChemistryAuthor(s): Younes Ahmadi, Mohammad Tahir Siddiqui, Qazi Mohd. Rizwanul Haq, Sharif Ahmad Present study reports a facile synthesis of surface-active antimicrobial hyperbranched polyurethane coatings using oleo-ethers of boric acid (BA) as branching and biocidal moiety (BHPU). The antimicrobial branching center was synthesized via polycondensation reaction of BA and vegetable oil-based diol. The structural characterization of synthesized BHPU and its linear counterpart was investigated using Fourier-transform infrared (FTIR) and nuclear magnetic resonance (1H, 13C, and 11B NMR) spectroscopy techniques. The cured coatings were examined by physico-mechanical, thermogravimetric (TG) analysis and differential scanning calorimetry (DSC). The antimicrobial behavior of these polymers against Gram-positive and Gram-negative bacteria was carried out by well diffusion technique. The appearance of zone of inhibition (ZOI) in case of BHPU confirmed its antimicrobial activity, which arisen due to the presence of cationic moiety in its structure. These investigations showed that the utilization of oleo-ethers of BA as branching agent in synthesis of BHPU coatings induced prominent effect on its physico-mechanical, thermal, and biocidal properties. In addition, soil burial study for 210 days was conducted on BHPU film to confirm its contact-killing mechanism against soil-borne bacteria. These results suggest the potential scope of BHPU in various applications such as long-term antimicrobial surface-active coatings for medical devices, packaging industry, paints, etc.Graphical abstractGraphical abstract for this article
       
  • Novel and highly effective composites of silver and zinc oxide
           nanoparticles with some transition metal complexes against different
           microorganisms

    • Abstract: Publication date: Available online 7 July 2018Source: Arabian Journal of ChemistryAuthor(s): A.S. Orabi, K.M. Abou El-Nour, M.F. Youssef, H.A. Salem Novel composites of Ag and ZnO nanoparticles with prepared transition metal complexes were obtained. The transition metal complexes are obtained by the interaction of the ligand N,N’-bis(salicylaldehyde)-o-phenylenediamine(H2B) with some transition metal ions (Co(II), Ni(II), Cu(II) and Zn(II)). The structures of the ligand and the formed complexes were characterized by elemental analysis, FTIR, UV-Vis, 1HNMR, mass spectra, thermal (TG/DTA), magnetic and conductivity measurements. The obtained complexes have the molecular formula [MB(H2O)x]. yH2O. The found conductivity revealed the non-electrolytic behavior of the formed complexes. The magnetic susceptibility and UV-Vis spectra indicated the octahedral structure of the formed complexes. The thermodynamic and kinetic parameters are estimated for the formed complexes. The interaction of the formed compounds with the FM-DNA was tested. The evaluation of the binding constant (Kb) using Bensi-Hildebrand plot, revealed the moderate interaction with electrostatic behavior. Silver and zinc oxide nanoparticles were prepared and characterized by XRD, UV-Vis, FTIR spectra and TEM analysis. The biological activity of the synthesized composites of Ag and ZnO nanoparticles with the prepared transition metal complexes were tested against some Gram positive and Gram negative bacteria as well as Fungi. The obtained inhibition zone supported the enhancement in the activity of the prepared compounds towards the target microorganism after forming the composites. Also, the interaction with the E.coli protein (FabH, PDB code: 1HNJ) was tested and evaluated using the docking operation with aid of some computational chemistry software. The obtained results agreed well with our experimental work.
       
  • Highly selective and sensitive optosensing of glutathione based on
           fluorescence resonance energy transfer of upconversion nanoparticles
           coated with a Rhodamine B derivative

    • Abstract: Publication date: Available online 6 July 2018Source: Arabian Journal of ChemistryAuthor(s): Thu-Thuy T. Nguyen, Bui The Huy, Salah M. Tawfik, Gerelkhuu Zayakhuu, Hyo Hyun Cho, Yong-Ill Lee A Glutathione (GSH) optical sensor with high sensitivity and exceptional selectivity was developed using one-step synthesized-upconversion nanoparticles (UCNPs, NaLuF4:Gd3+,Yb3+,Er3+) in conjunction with a Rhodamine B derivative (RBD). RBD was loaded on the surface of the UCNPs though non-covalent bonding to serve as an energy acceptor, while UCNPs served as energy donors. The sensor based on a coupling fluorescence resonance energy transfer (FRET) process at an excitation of 980 nm wavelength from UCNP to RBD with a ring-opening process of RBD after the addition of GSH. The sensing probe exhibits a remarkable limit of detection (LOD = 50 nM) for GSH through the enhancement of the fluorescence intensity of RBD at 592 nm, together with a concomitant reduction in the green band of the UCNPs. In addition, the sensing mechanism, characterization of UCNPs, and the selectivity of the fluorescence sensor toward GSH were discussed. The proposed sensor was evaluated on real human serum and urine samples and demonstrated as a highly selective and sensitive probe for the detection of GSH.
       
  • Effective Removal of Mercury(II) from Aqueous Solutions by Chemically
           Modified Graphene Oxide Nanosheets

    • Abstract: Publication date: Available online 6 July 2018Source: Arabian Journal of ChemistryAuthor(s): Fathi S. Awad, Khaled M. AbouZied, Weam M. Abou El-Maaty, Ahmad M. El-Wakil, M. Samy El-Shall Improved graphene oxide (IGO) is chemically modified with chloroacetic acid and ethylene diamine to form carboxylated improved graphene oxide (IGO-COOH), aminated improved graphene oxide (IGO-NH2), and imino-diacetic acid improved graphene oxide (Imino-IGO). These novel solid phase adsorbents are utilized to adsorb mercury ions from aqueous solutions. The IGO, IGO-COOH, IGO-NH2, and Imino-IGO adsorbents are fully characterized by FT-IR, UV-Vis, XPS, XRD, SEM, TEM, and Raman spectroscopy. Batch adsorption experiments are conducted to evaluate the adsorption of Hg(II) ions by IGO, IGO-COOH, and Imino-IGO under different conditions. The effects of pH, adsorbent dose, temperature, contact time, and initial concentrations on the removal of Hg(II) ions are studied. The results reveal that, at pH 5, the maximum adsorption capacity for the removal of mercury (mg Hg / g adsorbent) follows the order: Imino-IGO (230.0) < IGO-COOH (122.0) < IGO (24.0 mg/g), in which mercury ions’ complexation is highly dependent on the concentrations of (NH), and (OH) containing functional groups in the adsorbent.The IGO-COOH, and Imino-IGO adsorbents show 100% removal of Hg(II) at concentrations as low as 10 ppm. The equilibrium isotherms for evaluating the mechanism of adsorption process show good fits to the Langmuir model. The Imino-IGO could retain more than 93.0% of its original adsorption capacity after six adsorption-desorption cycles. All data confirmed that the Imino-IGO is a promising material to extract Hg (II) from wastewater.Graphical abstractGraphical abstract for this article
       
  • Oxidative desulfurization of fuels at room temperature using ordered
           

    • Abstract: Publication date: Available online 6 July 2018Source: Arabian Journal of ChemistryAuthor(s): Du Yue, Jiaheng Lei, Lina Zhou, Xiaodi Du, Zhenran Guo, Junsheng Li Ordered meso/macroporous H3PW12O40/SiO2 nanocomposites with high specific surface areas were prepared using cationic surfactant and monodispersed polystyrene spheres (PS) as dual-template. The characterization results of scanning electron microscopy (SEM), transmission electron microscopy (TEM), N2 adsorption-desorption, and small-angle XRD patterns confirmed the existence of ordered meso/macroporous structure and the wide-angle XRD patterns, Fourier transform infrared spectroscopy (FTIR), X-ray photoemission spectroscopy (XPS) measurements suggested the high dispersivity of the Keggin-type heteropolyacid (HPA) on silica matrix. There was an optimum value of cationic surfactant usage and proper calcination temperature of ordered meso/macroporous H3PW12O40/SiO2 catalyst leading to ultra-high specific surface areas. Furthermore, the ordered meso/macroporous H3PW12O40/SiO2 catalyst was evaluated for ultra-deep oxidative desulfurization (ODS) of cyclic sulphur-containing compounds using hydrogen peroxide (H2O2) as oxidant. Under optimum reaction conditions, dibenzothiophene (DBT) could be removed within 100 min at 30 °C by meso/macroporous H3PW12O40/SiO2 catalyst. The excellent catalytic activity should be attributed to the combination of ordered meso/macroporous architecture and high surface area of H3PW12O40/SiO2 catalyst which promoted the mass transport of reactants and products in the pore channel and provided more accessible catalytic active sites. In addition, the meso/macroporous H3PW12O40/SiO2 catalyst showed good stability with only 1.9% efficiency decreased after 6 cycles.
       
  • Bio-guided fractionation and characterization of powerful antioxidant
           compounds from the halophyte Inula crithmoїdes

    • Abstract: Publication date: Available online 6 July 2018Source: Arabian Journal of ChemistryAuthor(s): Inès Jallali, Pierre waffo Téguo, Abderrazek Smaoui, Jean-Michel Mérillon, Chedly Abdelly, Riadh Ksouri The investigation of natural and safe antioxidants from natural origin is highly encouraged since it was revealed that synthetic antioxidants have restricted use in foods due to their toxicological effects and suspected carcinogenic potential. Purification of most active phenolics from the halophyte Inula crithmoїdes was the objective fixed for this work. The separation of the flower phenolics was carried using centrifugal partition chromatography (CPC) and yielded 24 fractions. A bio-guided selection of the most active fractions was done based on their antioxidant activities. Fractions 2, 7, 11 and 19 were the most active ones, even more potent than positive controls BHT, BHA and ascorbic acid. The semi-preparative High Performance Liquid Chromatography (HPLC) purification of the antioxidant molecules from these active fractions and their identification by Nuclear Magnetic Resonance spectroscopy (NMR) revealed that the most potent phenolics of I. crithmoїdes are the chlorogenic acid and its two derivatives 3-p-coumaroyl-5-caffeoyl quinic acid and 1,5-di-O-caffeoylquinic acid, in addition to the quercetin and its derivative quercimeritrin. All identified compounds are powerful antioxidants, as they have many biological properties allowing their use in agro-food, pharmaceutical or cosmetic industries.Graphical abstractGraphical abstract for this article
       
  • Effect of number and position of methoxy substituents on fine-tuning the
           electronic structures and photophysical properties of designed
           carbazole-based hole-transporting materials for perovskite solar cells:
           DFT calculations

    • Abstract: Publication date: Available online 3 July 2018Source: Arabian Journal of ChemistryAuthor(s): Nuha Wazzan, Zaki Safi In perovskite solar cells (PSCs), the state-of-art Spiro-OMeTAD, which used as a hole-transporting material (HTM), suffered from complicated multistep synthesis and difficult purification that make this material cost ineffective, in addition to it being UV-unstable. Thus, new, cost-effective and easy to synthesize small organic molecules is still required. As reported, a carbazole-based compound (R01) was synthesized using a simple two steps method from low-cost commercially available compounds and used as an HTM. R01 exhibited higher conductivity and hole-mobility compared to that of the Spiro-OMeTAD. PSCs fabricated with R01 produced a power conversion efficiency of 12.03%, equivalent to that obtained in devices where Spiro-OMeTAD was the HTM. These findings highlighted R01 as a highly promising HTM with high performance, facile synthesis, and low cost. From a structural perspective, methoxy groups (–OCH3) in the HTM structure are controlling the HOMO level of the compound, apart from the critical role they play in anchoring the material onto the core perovskite layer. In this paper, we report a systematic study of the electronic structures and photophysical properties of twelve designed derivatives of R01. R01 was modified by substituting some hydrogen in the carbazole rings by two, four and six methoxy groups at different positions. The ground and excited state geometries are optimized by applying density functional theory (DFT) and its time-dependent functional (TDDFT), respectively. Detailed investigation of two factors: (i) the number and (ii) position of methoxy groups on the frontier molecular orbitals (FMOs), absorption and emission wavelengths, ionization potential, electron affinity, reorganization energies and charge mobility are examined and discussed. The electro-optical and nonlinear optical (NLO) properties are finely tuned in the R01 derivatives. By incorporating methoxy substituents into this carbazole-based compound, systematic design of potential materials for PSCs can be feasible.
       
  • Enhanced performance of BiFeO3@nitrogen doped TiO2 core-shell structured
           nanocomposites: Synergistic effect towards solar cell amplification

    • Abstract: Publication date: Available online 2 July 2018Source: Arabian Journal of ChemistryAuthor(s): Mohamed Mokhtar Mohamed, S.M. Reda, Ahmed A. Amer A core-shell nano-heterostructured perovskite BiFO3@nitrogen doped mesoporous TiO2 (BFO/n-TiO2) hydrothermally assembled via using citric acid and polyethlene glycol (PEG) was characterized through XRD, TEM, FTIR, UV–Vis diffuse reflectance, IPCE, N2 adsorption and impedance spectroscopy. It has been demonstrated that the photovoltaic yield of the 90%N-TiO2-10%BFO electrode achieves a power conversion efficiency (PCE) of 4.5%, which is 1.85, 2.5, 3 and 1202 times higher than those of 10%N-TiO2-90%BFO, 50%N-TiO2-50%BFO, n-TiO2 and pristine BFO, respectively. It is acknowledged that the former electrode exhibits a significant visible light harvesting capability, lowest band gap (Eg = 2.0 eV) as well as the highest IPCE% (36% at 460 nm) values. The EIS and capacitance results illustrated that 90%N-TiO2-10%BFO owns excessive charge carriers (e− − h+); compared to rest of nanocomposites, with a great sparation, to assist boosting the PCE value. This was highly aided by the surface defects seen on the core represented by BFO, which worked as a rational carrier trapper between the N719 dye and the n-TiO2 shell structure. The surface texturing properties of the nanocomposite forming the 90%N-TiO2-10%BFO electrode including SBET (Asahi et al., 2001) and pore volume (0.48 cm3 g−1) have shared significantly in improving the conversion efficiency of such p-n heterojunction based solar cells; which never achieved as such in all BFO-based solar cell devices, with acceptable tunability.
       
  • A new way of assessing the interaction of a metallic phase precursor with
           a modified oxide support substrate as a source of information for
           predicting metal dispersion

    • Abstract: Publication date: Available online 2 July 2018Source: Arabian Journal of ChemistryAuthor(s): Waldemar Nowicki, Zbigniew Piskuła, Piotr Kirszensztejn, Dorota Bartkowiak, Erhard Kemnitz Well-dispersed nanosized clusters of metallic platinum were obtained by decomposition of ethylenediamine complexes immobilized on amorphous silica surfaces. Samples before reduction were obtained by potentiometric titration in a heterogeneous liquid/solid system in different pH ranges. The proposed easy and inexpensive method for characterization of metal-ligand interactions provides new information about phenomena taking place at the molecular level, depending on the type of support, type of agent coupling with the ligand, and type of metal. The systems obtained were characterized by TEM, XRPD and hydrogen chemisorption. The catalytic properties of the systems studied were tested in N2O decomposition.
       
  • Adsorption thermodynamics of cationic dyes (methylene blue and crystal
           violet) to a natural clay mineral from aqueous solution between 293.15 and
           323.15 K

    • Abstract: Publication date: July 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 5Author(s): Omer Sakin Omer, Mohammed Ali Hussein, Belal H.M. Hussein, Arbi Mgaidi Wastewater from dyestuff production is one of the main water pollutants. Several methods have been applied for the remediation of contaminated water. Currently, adsorption using a cheap, abundant, and environmental-friendly adsorbent such as natural clay is the simplest and most useful method. This study aimed to determine the enthalpies of adsorption of the organic cationic dyes, methylene blue (MB) and crystal violet (CV), from polluted water onto a natural clay mineral. Early on, we performed mineralogical and textural analyses of a clay sample using various techniques, namely X-ray diffraction, scanning electron microscopy/energy dispersive X-ray spectroscopy, Brunauer-Emmett-Teller analysis, Fourier-transform infrared spectroscopy, and differential scanning calorimetry, before and after adsorption. The experimental results showed that this adsorbent is a mesoporous and non-swelling clay with illite and kaolinite as the major components. The effects of various parameters such as contact time, pH, and temperature were examined. The experimental data were analyzed using the linear forms of the Langmuir and Freundlich isotherm models and showed a good fit with the Langmuir equation for MB adsorption. Thermodynamic parameters such as the changes in Gibbs free energy, enthalpy, and entropy were determined from batch experiments. Results revealed that the adsorption of MB onto illitic clay was endothermic, while that of CV was an exothermic and spontaneous process.
       
  • Development and performance analysis of PEMFC stack based on bipolar
           plates fabricated employing different designs

    • Abstract: Publication date: July 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 5Author(s): M. ElSayed Youssef, R.S. Amin, K.M. El-Khatib A low-temperature proton exchange membrane fuel cell (LT-PEMFC) is a promising clean and effective technology for power generation because of its simplified water and heat management. Due to the non-uniform of H2 and air distributions within fuel cells, the stack design is one of the key factors to enhance the performance and efficiency of LT-PEMFC. In this study, a single, two cells, 6 cells and 11 cells LT-PEMFC stack was investigated with cell active area 114 cm2, Nafion membrane 112 and catalyst loading 0.4 mg/cm2 working at 25 °C and atmospheric pressure using hydrogen and air as a fuel and oxidant, respectively. The power output that is obtained from each stack is presented and the overall power output is compared with single cell stack. The stack prototype has been fabricated, constructed and tested producing a maximum value of 70 W electrical power using 11 cells stack.
       
  • Evaluation of non-covalent interactions of chlorambucil (monomer and
           dimer) and its interaction with biological targets: Vibrational frequency
           shift, electron density topological and automated docking analysis

    • Abstract: Publication date: July 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 5Author(s): T. Karthick, Poonam Tandon, Karnica Srivastava, Swapnil Singh Chlorambucil is a well-known chemotherapy drug that is being used to treat chronic myelogenous leukemia. As it contains ten flexible rotational bonds, the possible spatial conformations have been identified theoretically. The spectral signatures of monomer and dimer structures of chlorambucil and the frequency shifts due to non-covalent interactions (NCIs) have been illustrated using FT-IR and FT-Raman spectra. The bond correlation between carbon and hydrogen nuclei of chlorambucil has been obtained using 2D-HSQC NMR spectrum. The assignments of harmonic normal modes have been done in order to find the vibrational contributions of each functional group. Besides the spectroscopic studies, the electron density based quantum topological atoms in molecule analysis have been performed to explore the possible interactions between the non-bonded atoms. The reduced density gradient and isosurface plots have been used in this study to understand the strength of NCIs. The charge delocalization patterns of monomer and dimer structures were explained so as to investigate the chemical stability profile. The active sites for the electrophilic and nucleophilic attack on the monomer conformers have been determined by applying Hirshfeld charges and atomic spin densities into Fukui and Parr functions, respectively. From the automated docking analysis, it is found that chlorambucil interacts with the aldo-keto reductase family 1 (AKR1B1, AKR1B10, AKR1B15) and FAD-linked sulfhydryl oxidase ALR proteins through strong hydrogen bonds and shows a potential inhibition. In order to take into account the interactions ranging from short to long range, the modern density functionals viz. M06-2X, wB97XD, B97D which includes dispersion-corrected repulsion terms have been employed and the theoretical results were found coincide with the experimental observations.
       
  • Inside Front Cover - Editorial Board

    • Abstract: Publication date: July 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 5Author(s):
       
  • Adsorption of aflatoxin B1 on magnetic carbon nanocomposites prepared from
           bagasse

    • Abstract: Publication date: July 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 5Author(s): Muhammad Zahoor, Farhat Ali Khan A novel adsorbent for the removal of aflatoxin from poultry feed was prepared from bagasse and was characterized by surface area analyzer, SEM, XRD, FTIR, TG/DTA and EDX. A specially designed chamber was used for the preparation of the adsorbent. SEM, XRD and FTIR analysis showed the iron oxide presence on the adsorbent surface. The adsorption parameters were determined for aflatoxin adsorption using Freundlich and Langmuir isotherms. The equilibrium time was 115 min for 200 ppm at pH 3 while 150 min at pH 7. At high pH there was a decline in percent adsorption. Best fit was obtained with pseudo first order kinetics model for the kinetics data of adsorption. The value of ΔS0 (30.67 kJ mol−1 deg−1) was positive while that of ΔH0 (−5.9 kJ mol−1) and ΔG0 (−9.303, −9.610, −9.916 and −10.226 kJ mol−1 correspond to 30, 40, 50 and 60 °C) was negative. The increase in ΔG0 values with temperature showed that the adsorption process was favorable at high temperature.
       
  • Novel supercapacitor electrodes based semiconductor nanoheterostructure of
           CdS/rGO/CeO2 as efficient candidates

    • Abstract: Publication date: July 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 5Author(s): Asma A. Ali, Ahmed Abdel Nazeer, Metwally Madkour, Ali Bumajdad, Fakhreia Al Sagheer In this study, we have synthesized metal oxide/metal sulphide based nanoheterostuctures mediated with graphene nanosheets. The synthesized nanoheterostructures were characterized via different techniques such as XRD, XPS, and TEM. The electrochemical characteristics of the investigated nanoheterostucture (CdS/rGO/CeO2) were investigated through electrochemical impedance spectroscopy (EIS), cyclic voltammetry (CV), and galvanostatic charge-discharge. The specific capacitance of the single rGO, binary CdS/CeO2 and ternary CdS/rGO/CeO2 heterostructures were measured. The CdS/rGO/CeO2 nanoheterostucture showed the most excellent cycling stability with high specific capacitance of 407 F g−1 achieved at a charge-discharge rate of 1 A/g. The investigated supercapacitor retained about 96% of the initial energy density after charge-discharge at a 10 A/g for 5000 cycles. The ternary CdS/rGO/CeO2 nanoheterostucture revealed the best specific capacitance as the graphene nanosheets increased interfacial electron transfer. The results revealed that the investigated novel nanoheterostucture is among the best reported ones in the literature.
       
  • DFT calculations, spectroscopic studies, thermal analysis and biological
           activity of supramolecular Schiff base complexes

    • Abstract: Publication date: July 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 5Author(s): Omaima E. Sherif, Nora S. Abdel-Kader Metal complexes of Schiff base (H2L) prepared from condensation reaction of o-phenylenediamine and 6-formyl-7-hydroxy-5-methoxy-2-methylbenzopyran-4-one with metal ions: Mn(II), Co(II), Ni(II) and Cu(II) were synthesized. Different analysis tools such as elemental analyses, mass spectra, Fourier transform infrared (FTIR), thermal analysis, conductivity, electronic spectra and magnetic susceptibility measurements are all used to elucidate the structure of the prepared metal complexes. The ligand behaves as a monobasic bidentate in case of mononuclear NiHL and CoHL complexes and acts as dibasic tetradentate in binuclear Mn2L and Cu2L complexes. All formed complexes are non-electrolytes. The thermal decomposition of Mn2L and CoHL complexes was studied by thermogravimetry/derivative thermogravimetry (TG/DTG). The Schiff base and its complexes were screened for antibacterial activities. The Mn2L Complex has the highest antimicrobial activity among the complexes almost close to that of the standard. Density Functional Theory (DFT) calculations at the B3LYP/3-21G level of theory have been carried out to investigate the equilibrium geometry of the ligand. The optimized geometry parameters of the complexes were evaluated using LANL2DZ basis set. Moreover, total energy, energy of HOMO and LUMO and Mullikan atomic charges were calculated. In addition, dipole moment and orientation have been performed.
       
  • Annona muricata: A comprehensive review on its traditional medicinal uses,
           phytochemicals, pharmacological activities, mechanisms of action and
           toxicity

    • Abstract: Publication date: July 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 5Author(s): Ana V. Coria-Téllez, Efigenia Montalvo-Gónzalez, Elhadi M. Yahia, Eva N. Obledo-Vázquez Annona muricata L. (Magnoliales: Annonaceae) is a tropical plant species known for its edible fruit which has some medicinal merits, but also some toxicological effects. This review focuses on the phytochemicals contents, bioactivity, biological actions and toxicological aspects of extracts and isolated compounds, as well as medicinal uses of A. muricata, with the objective of stimulating further studies on extracts and fruit pulp used for human consumption. Traditional medicinal uses of A. muricata have been identified in tropical regions to treat diverse ailments such as fever, pain, respiratory and skin illness, internal and external parasites, bacterial infections, hypertension, inflammation, diabetes and cancer. More than 200 chemical compounds have been identified and isolated from this plant; the most important being alkaloids, phenols and acetogenins. Using in vitro studies, extracts and phytochemicals of A. muricata have been characterized as an antimicrobial, anti-inflammatory, anti-protozoan, antioxidant, insecticide, larvicide, and cytotoxic to tumor cells. In vivo studies of the crude extracts and isolated compounds of A. muricata were shown to possess anxiolytic, anti-stress, anti-inflammatory, contraceptive, anti-tumoral, antiulceric, wound healing, hepato-protective, anti-icteric and hypoglycemic activities. In addition, clinical studies support the hypoglycemic activity of the ethanolic extracts of A. muricata leaves. Mechanisms of action of some pharmacological activities have been elucidated, such as cytotoxic, antioxidant, antimicrobial, antinociception and hypotensive activities. However, some phytochemical compounds isolated from A. muricata have shown a neurotoxic effect in vitro and in vivo, and therefore, these crude extracts and isolated compounds need to be further investigated to define the magnitude of the effects, optimal dosage, mechanisms of action, long-term safety, and potential side effects. Additionally, clinical studies are necessary to support the therapeutic potential of this plant.
       
  • Characterization of a sensitive biosensor based on an unmodified DNA and
           gold nanoparticle composite and its application in diquat determination

    • Abstract: Publication date: July 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 5Author(s): Ling Mei Niu, Ying Liu, Kao Qi Lian, Li Ma, Wei Jun Kang DNA usually adsorbs gold nanoparticles by virtue of mercapto or amino groups at one end of a DNA molecule. However, in this paper, we report a sensitive biosensor constructed using unmodified DNA molecules with consecutive adenines (CA DNA) and gold nanoparticles (GNPs). The CA DNA–GNP composite was fabricated on gold electrodes and characterized by using of scanning electron microscopy (SEM), electrochemical impedance spectroscopy (EIS) and the electrochemical method. Using an electrochemical quartz crystal microbalance (EQCM), the mechanism by which the CA DNA and GNPs combined was also studied. The modified electrode exhibited an ultrasensitive response to diquat. Differential pulse voltammetry (DPV) was used to study the linear relationships between concentrations and reduction peak currents, ranging from 1.0 × 10−9 M to 1.2 × 10−6 M. The detection limit of it is 2.0 × 10−10 M. The feasibility of the proposed assay for use in human urine and grain was investigated, and the satisfactory results were obtained.
       
  • Magnesium incorporated hydroxyapatite nanoparticles: Preparation,
           characterization, antibacterial and larvicidal activity

    • Abstract: Publication date: July 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 5Author(s): B. Gayathri, N. Muthukumarasamy, Dhayalan Velauthapillai, S.B. Santhosh, Vijayshankar asokan Mosquito-borne diseases cause several deaths every year in tropical and subtropical climate countries. Control of vectors is an alarming problem in today’s world due to the resistance matters. In this study magnesium incorporated hydroxyapatite nanoparticles have been synthesized by microwave irradiation method. Magnesium chloride hexahydrate (MgCl2·6H2O) calcium nitrate tetra hydrate (Ca (NO3)2·6H2O) and disodium hydrogen phosphate (Na2HPO4) were used as magnesium, calcium and phosphorous sources to prepare hydroxyapatite nanoparticles. The FT-IR studies show the presence of hydroxyl and phosphate functional groups. The structural properties have been studied using X-ray diffraction (XRD), Field Emission Scanning Electron Microscope (FESEM) and Transmission Electron Microscope (HRTEM). The energy dispersive X-ray analysis (EDAX) revealed the presence of Ca, Mg, P and O in the prepared samples. The antibacterial activity of the as-synthesized nanoparticles was evaluated against two prokaryotic strains, the gram negative bacteria Escherichia coli for three different concentrations of as-synthesized nanoparticles and they showed excellent antibacterial activity. The as-synthesized Mg-HAp nanoparticles were tested against fourth instar larvae of Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus and the nanoparticles exhibited significant mortality against the selected mosquitoes. The observed results suggest that the magnesium incorporated hydroxyapatite nanoparticles have the potential to be used as an effective mosquito larvae control agent against Ae. aegypti, An. stephensi, and Cx. quinquefasciatus. From the detailed literature review it has been observed that no work has been carried out so far on the larvicidal activity using hydroxyapatite (HAp) nanoparticles and magnesium substituted hydroxyapatite (Mg-HAp) nanoparticles.
       
  • Effect of homogeneous acidic catalyst on mechanical strength of
           trishydrazone hydrogels: Characterization and optimization studies

    • Abstract: Publication date: July 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 5Author(s): Nor Hakimin Abdullah, Wan Azelee Wan Abu Bakar, Rafaqat Hussain, Mohd Bakri Bakar, Jan H. van Esch Characterization utilizing X-ray photoelectron spectroscopy (XPS) revealed the presence of all the expected elements found in trishydrazone hydrogels (3). Morphological study on confocal laser scanning microscopy (CLSM) and atomic force microscopy (AFM) revealed the branching and bundling of fibers that led hydrogels network as well as the presence of cross-linked nanofibrillar network structure. A three-factor three-level Box Behnken design was implemented to study the concurrent effects of three main variables (concentration of precursor; 10–20 mM, pH; 3–7, and concentration of buffer; 50–150 mM) on mechanical strength of hydrogels. Analysis of variance (ANOVA) was conducted to investigate the potential interactive and quadratic effects between these variables and revealed that interaction between the pH value and the concentration of buffer (X2X3) showed a significant effect on the response since the significance of the design model (p-value) was set at
       
  • Influence of the ligand nature on the in situ laser-induced synthesis of
           the electrocatalytically active copper microstructures

    • Abstract: Publication date: July 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 5Author(s): Lev S. Logunov, Maxim S. Panov, Liubov A. Myund, Ilya I. Tumkin, Evgeniia M. Khairullina, Mikhail N. Ryazantsev, Irina A. Balova, Vladimir A. Kochemirovsky In this work we demonstrate the role of a ligand in formation of the conductive and electrocatalytically active copper microstructures produced using the in situ laser-induced metal deposition technique. For this purpose, the alkaline solutions of different concentrations containing copper(II) chloride and Rochelle salt, which is used as the ligand and exhibits both coordination and reduction properties, were studied by ATR-FTIR, UV–Vis, and Raman spectroscopy. According to spectroscopic studies and theoretical considerations, it was observed that at certain concentrations and proportion of copper(II) chloride and sodium potassium tartrate, and also within pH range between 7 and 13 the components of the plating copper solution form the tartrate copper complex, in which copper ion is coordinated by four hydroxyl groups of the ligand and two hydroxyl groups of the environment. As a result, the laser-induced deposition from solutions, where copper coordination occurs via hydroxyls rather than through other functional groups (e.g. carboxylate), results in the synthesis of the sensory active materials. Furthermore, we figured out that the presence of the reducing agents such as polyols in the plating copper solution also enhances the electrical conductivity and electrochemical characteristics of the resulting copper microdeposits, among which sorbitol displays the most attractive results. Thus, it was shown that the regime of copper coordination in an organic ligand and number of hydroxyl groups in a ligand and a reducing agent directly affect the properties of the synthesized copper microstructures. In addition, the overall results obtained in this study are quite useful for better understanding the mechanisms of the laser-induced metal deposition process, and very perspective for development and design of new non-enzymatic electrochemical sensors and biosensors.Graphical abstractGraphical abstract for this article
       
  • Antibacterial, in vitro antitumor activity and structural studies of
           rhodium and iridium complexes featuring the two positional isomers of
           pyridine carbaldehyde picolinic hydrazone ligand

    • Abstract: Publication date: July 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 5Author(s): Narasinga Rao Palepu, J. Richard Premkumar, Akalesh Kumar Verma, Kaushik Bhattacharjee, S.R. Joshi, Scott Forbes, Yurij Mozharivskyj, Kollipara Mohan Rao Half-sandwich organometallic rhodium and iridium complexes [1–6] have been synthesized with ligands L1 (L1 = Pyridin-2-ylmethylene picolinichydrazine) and L2 (L2 = Pyridin-3-ylmethylene picolinichydrazine). Treatment of [{Cp∗MCl2}2] (M = Rh/Ir) with L1 in methanol has yielded mononuclear cationic complexes such as [{Cp∗M(L1N∩N)Cl}]PF6 where {M = Rh (1) and Ir (2)} and dinuclear complexes such as [{(Cp∗MCl)2(L1N∩N, N∩N)}]PF6 where {M = Rh (3) and Ir (4)} in 1:2 and 1:1 metal dimer to ligand ratios respectively. Reactions of [{Cp∗MCl2}2] with L2 in both 1:2 and 1:1 metal dimer to ligand ratios have yielded two metalla-macrocyclic dinuclear and dicationic complexes such as [{Cp∗M(L2N∩NμN)}2](PF6)2 where {M = Rh (5) and Ir (6)}. Spectroscopic and crystallographic data were used to elucidate the structures of the synthesized complexes. The in vitro antitumor evaluation of the complexes 1 and 2 by fluorescence based apoptosis study revealed their antitumor activity against Dalton’s ascites lymphoma (DL) cells. The antibacterial evaluation of complexes 1, 2, 5 and 6 by agar well-diffusion method revealed their significant activity against the two species considered viz., Proteus vulgaris (MTCC 426) and Vibrio parahaemolyticus (MTCC 451) with zone of inhibition up to 43 mm. The docking study with few key enzymes associated with cancer viz., ribonucleotide reductase, thymidylate synthase, thymidylate phosphorylase and topoisomerase II revealed their strong interactions with complexes under study. Complexes 1–6 exhibited a HOMO (highest occupied molecular orbital) – LUMO (lowest unoccupied molecular orbital) energy gap from 2.95 eV to 3.59 eV. TDDFT calculations explain the nature of electronic transitions and found well agreement with the experiments.Graphical abstractReaction of rhodium and iridium precursor compounds with ligand L1 in 1:2 and 1:1 metal dimer to ligand ratio has yielded mononuclear and dinuclear complexes respectively. In contrast, ligand L2 has yielded dinuclear metalla-macrocyclic complexes irrespective of the ratios. Complexes 1 and 2 are more cytotoxic against Dalton’s ascites lymphoma (DL) cells and comparatively less toxic on normal cells. Complexes 1, 2, 5 and 6 are considerably bactericidal against the two species considered viz., Proteus vulgaris and Vibrio parahaemolyticus.Graphical abstract for this article
       
  • A study of vitamin B influence on the morphology, roughness, and
           reflectance of electropolished aluminum in H3PO4 –H2SO4 mixture

    • Abstract: Publication date: Available online 30 June 2018Source: Arabian Journal of ChemistryAuthor(s): Fatma M. Abouzeid, Haya A. Abubshait The galvanostatic polarization method used to determine the electrodissolution process of aluminum metal (Al) in acids (phosphoric acid; H3PO4, and sulfuric acid; H2SO4) mixture solution. The investigate of anode potential–limiting current (IL) measured in solution that include of the vitamins B (VB). This research showed an improvement produced in electropolishing (EP) of Al, in the exist of VB, which occurs through adsorption of molecules on the metal surface. The comparison study established by using a different additive: vitamin B1 (VB1), vitamin B2 (VB2), vitamin B6 (VB6), and vitamin B12 (VB12) to evaluate the best one. Adding of VB to Al dissolution bath leads to reduce IL, where the minimum obtained's value for VB12 above other type's value, which according to its chemical structure. By indicating the increases in the surface viscosity of the additives formed over Al, which influences the planarization capacity of the electrolyte. VB adsorbed on the Al surface found to conserve the energy established, resulting in the increased charge transfer resistance and the increase of the overpotential for oxygen and hydrogenThe impact effect of the temperature (T) and acid ratios (v/v %) in a solution are evaluated to determine the preferable conditions in the dissolution process. The calculated IL value will increase by increasing solution's T in moderated acid ratio. A limiting plateau observed at 35°C in 60% H3PO4: 40% H2SO4 mixture solution, considered an ideal condition for EP of Al. Activation parameter's values confirm that the dissolution is an endothermic procedure and a character of diffusion.The influence of increasing concentration (C) (1 x 10-4 to 10 x 10-4 mol. L-1) of VB completed and comprehend, to deduce the relationship between IL and C. Surface morphology, reflection, and roughness of polished samples examined with a scanning electron microscope (SEM), Vis-IR spectroscopy and profilometry. Appreciated and effective results in morphology SEM images occurred at 35°C by adding optimum C (5x 10-4 mol. L-1) of VB to a solution mixture; representing a perfect in surface texture. The highest reflectance and lowest roughness values under optimal condition recorded to confirm the SEM results.
       
  • True-remanent, resistive-leakage and mechanical studies of flux grown
           0.64PMN-0.36PT single crystals

    • Abstract: Publication date: Available online 30 June 2018Source: Arabian Journal of ChemistryAuthor(s): Abhilash J. Joseph, Nidhi Sinha, Sahil Goel, Abid Hussain, Binay Kumar Ferroelectric single crystals of 0.64Pb(Mg1/3Nb2/3)O3-0.36PbTiO3 (PMN-PT), which have attracted lot of attention because of its excellent ferroelectric and piezoelectric response, has been successfully grown in the vicinity of morphotropic phase boundary, using high temperature solution method with PbO/B2O3 as flux. The crystals were characterized for its dielectric, ferroelectric, piezoelectric and pyroelectric properties along with the investigation of its domain structure. A high Curie temperature (Tc = 190 °C) was observed in the dielectric study. Well-saturated ferroelectric hysteresis loops with high remanent polarization, good switching and fatigue resistant nature indicated the high ferroelectric quality of the crystals. A high value of piezoelectric coefficient (d33∗ = 1398 pm/V) was obtained from the butterfly loops. True-remanent hysteresis study unveiled the practically usable polarization value, which actually serves as memory component in devices and has never been reported for PMN-PT crystals. Time-dependent compensated hysteresis analysis was carried out to study the resistive-leakage nature of the grown crystals which is also a new study for this system. Weibull statistics was used to analyze the distribution of hardness number and to find the values of critical load for the flux grown PMN-PT crystals which helps to critically analyze materials suitability for device fabrication.Graphical abstractGraphical abstract for this article
       
  • A Review on the Classifications of Organic/Inorganic/Carbonaceous Hole
           Transporting Materials for Perovskite Solar Cell Application

    • Abstract: Publication date: Available online 28 June 2018Source: Arabian Journal of ChemistryAuthor(s): Selvakumar Pitchaiya, Muthukumarasamy Natarajan, Agilan Santhanam, Vijayshankar Asokan, Akila Yuvapragasam, Venkatraman Madurai Ramakrishnan, Subramaniam E Palanisamy, Senthilarasu Sundaram, Dhayalan Velauthapillai The rapid increase in the efficiency of perovskite solar cells (PSCs) in last few decades have made them very attractive to the photovoltaic (PV) community. However, the serious challenge is related to the stability under various conditions and toxicity issues. A huge number of articles have been published in PSCs in the recent years focusing these issues by employing different strategies in the synthesis of electron transport layer (ETL), active perovskite layer, hole transport layer (HTL) and back contact counter electrodes. This article tends to focus on the role and classifications of different materials used as HTLs in influencing long-term stability, in improving the photovoltaic parameters and thereby enhancing the device efficiencies. Hole Transport Materials (HTMs) are categorized by dividing into three primary types, namely; organic, inorganic and carbonaceous HTMs. To analyze the role of HTMs in detail, we further divide these primary types of HTMs into different subgroups. The organic-based HTMs are subdivided into two categories, namely; long polymer HTMs small molecule HTMs and cross-linked polymers and the inorganic HTMs have been classified into nickel (Ni) derivatives and copper (Cu) derivatives based HTMs, p-type semiconductor based HTMs and transition metal based HTMs. We further analyze the dual role of carbonaceous materials as HTMs and counter electrode in the perovskite devices. In addition, in this review, an overview of the preparation methods, and the influence of the thickness of the HTM layers on performances and stability of the perovskite devices are also provided. We have carried out a detailed comparison on the various classifications of HTMs based on their cost-effectiveness and considering their role on effective device performances. This review further discusses the critical challenges involved in the synthesis and device engineering of HTMs. This will give the reader provides a better insight into the state of the art of perovskite solar devices.
       
  • The gene transfection and endocytic uptake pathways mediated by PEGylated
           PEI-entrapped gold nanoparticles

    • Abstract: Publication date: Available online 28 June 2018Source: Arabian Journal of ChemistryAuthor(s): Aijun Li, Jieru Qiu, Benqing Zhou, Bei Xu, Zhijuan Xiong, Xinxin Hao, Xiangyang Shi, Xueyan Cao The development of gene vectors is the vital step in gene therapy. The cationic polymer polyethylenimine (PEI) is widely applied as an efficient and low cost nonviral gene vehicle. However, its further practical applications in gene therapy are limited due to its high cytotoxicity. To obtain safe and efficient gene vectors, hydrophilic polyethylene glycol (PEG) has been conjugated onto its surface due to its good biocompatibility, and the PEGylated PEI was used as a template to entrap gold nanoparticles (Au NPs) with different Au atom/PEI molar ratios (25:1, 50:1, 100:1, and 200:1, respectively). The formed PEGylated PEI-entrapped Au NPs (PEG-Au PENPs) and their cytotoxic effects as well as ability to transfect plasmid DNA (pDNAs) to HeLa cells were analyzed using Cell Counting Kit-8 (CCK-8) assay, flow cytometry and confocal microscopic imaging. To further understand cell internalization pathway of PEG-Au PENPs, several pharmacologic inhibitions of endocytic pathways were conducted. Our results revealed that the PEG-Au PENPs were not only able to transfect pDNAs into cells with decreased cytotoxicity, but also showed high transfection efficiency compared with PEI alone. The cellular uptake data indicated that the clathrin-mediated endocytosis is the main pathway in the internalization of the formed polyplexes. These findings suggested that the developed PEG-Au PENPs may serve as a safe gene carrier with non-compromised DNA transfection efficiency and promote the further development of efficient and safe gene delivery strategies based on nanoparticles.
       
  • Biomonitoring and risk assessment of organochlorine pesticides among Saudi
           adults

    • Abstract: Publication date: Available online 26 June 2018Source: Arabian Journal of ChemistryAuthor(s): Nasser Al-Daghri, Sherif H. Abd-Alrahman, Kaiser Wani, Amaresh Panigrahy, Philip G. McTernan, Omar S. Al-Attas, Majed S. Alokail The present study aimed to determine the serum organochlorine pesticides (OCPs) levels and risk of exposure among Saudi adults. Most OCPs are considered as endocrine-disrupting chemicals, and exposure can induce adverse health effects in both humans and wildlife. Serum OCP levels have not been documented in the Saudi population. Serum OCP concentrations were quantified using gas chromatography mass spectrometry (GC-MS/MS) in 302 serum samples collected from adult Saudis. All studied OCPs were detected in all participants. High concentrations of DDT and its metabolites (DDE and DDD) were detected in both males and females, with concentrations being significantly higher in males. High concentrations of 2,4-DDE, 4,4-DDE, and gamma-HCH were detected (18.31, 16.12, and 15.15 ng g−1 lipid and 5.9, 7.1, and 8.6 ng g−1 lipid for males and females, respectively). Alpha-HCH, Beta-HCH, 2,4-DDT, and 4,4-DDT were detected at concentrations lower than 2 ng g−1. Levels of OCPs varied according to age and body mass index (BMI). Serum concentrations of OCPs significantly differed between Saudi males and females and were influenced by age and BMI. This study is the first to document serum OCP concentrations in Saudi adults from Riyadh, KSA. Monitoring programs are suggested for evaluating serum OCP concentrations in the general population to track toxicity levels and serve as an indicator of possible adverse health effects.
       
  • Impact of purification on iota carrageenan as solid polymer electrolyte

    • Abstract: Publication date: Available online 26 June 2018Source: Arabian Journal of ChemistryAuthor(s): Noor Azlina Abdul Ghani, Rizafizah Othaman, Azizan Ahmad, Farah Hannan Anuar, Nur Hasyareeda Hassan Iota carrageenan purification was done by dissolving iota carrageenan powder in water. The purified iota carrageenan powder was analyzed by using Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy and X-Ray Diffraction (XRD) analyses. The powder was used to form a purified iota carrageenan film based solid polymer electrolyte. Ionic conductivity value of the film was determined by using Electrochemical Impedance Spectroscopy (EIS). The conductivity value for purified iota carrageenan was 1.57 × 10−5 S cm−1 higher than iota carrageenan film. The films were analyzed by using ATR-FTIR, XRD and Field Emission Scanning Electron Microscopy with Energy Dispersive X-Ray Spectroscopy (FESEM-EDX). Electrochemical stability of iota carrageenan was improved after purification and had more ionic conduction as compared to iota carrageenan without purification.
       
  • Ti3+ self-doped rutile/anatase/TiO2(B) mixed-crystal tri-phase
           heterojunctions as effective visible-light-driven photocatalysts

    • Abstract: Publication date: Available online 23 June 2018Source: Arabian Journal of ChemistryAuthor(s): Junyan Kuang, Zipeng Xing, Junwei Yin, Zhenzi Li, Siyu Tan, Meng Li, Jiaojiao Jiang, Qi Zhu, Wei Zhou Ti3+ self-doped rutile/anatase/TiO2(B) mixed-crystal tri-phase heterojunctions photocatalysts are fabricated via hydrothermal approach and mechanochemical process, followed by in-situ solid-state chemical reduction approach. The as-prepared samples are characterized by X-ray diffraction, Raman, scanning electron microscopy, transmission electron microscopy, X-ray photoelectron spectroscopy, and UV–vis diffuse reflectance spectroscopy. The photocatalysts are consisted by anatase/rutile TiO2 nanoparticles and 1D TiO2(B) single-crystalline nanorods, which form rutile/anatase/TiO2(B) tri-phase heterojunctions. The visible-light-driven photocatalytic degradation rates of methyl orange and phenol are up to ∼98 and 97%, which are 2.2 and 1.8 times higher than that of commercial Degussa P25, 2.3 and 2.2 times higher than that of pure TiO2(B) as well. The enhancement can be attributed to the synergistic effect of special nanostructure, tri-phase heterojunctions, oxygen vacancy and Ti3+ self-doping, which facilitates the absorption of visible light and the spatial separation of photo-generated charge carriers. This work provides a new perspective for designing high-active visible-light-driven photocatalyst in future.
       
  • Multifunctionalization of cyanuric chloride for the stepwise synthesis of
           potential multimodal imaging chemical entities

    • Abstract: Publication date: Available online 22 June 2018Source: Arabian Journal of ChemistryAuthor(s): Mário J.F. Calvete, Sara M.A. Pinto, Hugh D. Burrows, M. Margarida C.A. Castro, Carlos F.G.C. Geraldes, Mariette M. Pereira We report a synthetic strategy to combine different moieties in a single structure using cyanuric chloride (2,4,6-trichlorotriazine) as a starting platform for preparing potential bioimaging agents. This reacted with macrocycles of the porphyrin family and DOTA type metal chelators through mono-, di- and tri- substitution of its chlorine atoms by appropriate nucleophiles, controlling the stepwise by temperature, to produce a system that opens the potential for biomedicinal applications. Porphyrins were chosen as one of the sensing arms, based on their rich structural chemistry, and excellent photophysical properties, while DO3A was used since it can form a versatile aminopropionate functionalized metal ion chelator. All new compounds were fully characterized, both spectroscopically and photophysically.
       
  • Green synthesized SiO2@OPW nanocomposites for enhanced Lead
           (II) removal from water

    • Abstract: Publication date: Available online 22 June 2018Source: Arabian Journal of ChemistryAuthor(s): Jyoti Saini, V.K. Garg, R.K. Gupta The orange peel waste (OPW) was chemically spiked with silica nanospheres, to develop a novel, nanocomposite (SiO2@OPW) with enhanced adsorption capacity for heavy metals. The dispersion of silica nanospheres into orange peel waste was confirmed by XRD, FTIR, TEM, SEM and EDX. Adsorption of Pb2+ ions onto SiO2@OPW was studied in batch mode under varying process conditions such as pH, metal concentration, contact time and adsorbent dosage. The maximum adsorption capacity for OPW and SiO2@OPW was 166.7 mg/g and 200.0 mg/g, respectively calculated employing the Langmuir isotherm model. The kinetic data followed pseudo second order and intraparticle diffusion models. The maximum removal of Pb2+ ions was at pH = 6.0, adsorbent dosage = 0.02 g/L and contact time 60 min. Regeneration and reusability of SiO2@OPW was studied for five cycles. Owing to reusability and high adsorption capacity, SiO2@OPW nanocomposites may be considered as a promising adsorbent for the removal of heavy metals from water and wastewater.
       
  • Determination of nitrosamines in skin care cosmetics using Ce-SBA-15 based
           stir bar-supported micro-solid-phase extraction coupled with gas
           chromatography mass spectrometry

    • Abstract: Publication date: Available online 22 June 2018Source: Arabian Journal of ChemistryAuthor(s): Khalid Alhooshani Improvement for nitrosamine detections, particularly in consumables and products applied to skin is a growing area of research due to implications of nitrosamines on human health. In this study, mesoporous silica, SBA-15 was doped with various ceria loadings and used in the stir bar-supported micro-solid-phase extraction (SB-µ-SPE) of nitrosamines in cosmetic samples. The synthesized sorbents were characterized using field emission scanning electron microscopy and energy dispersive X-ray spectrometry. The effects of extraction variables (sorbent type and amount; desorption time, solvent, and volume; extraction time; and ionic strength) were determined. This newly improved method provides good linear range (R2 value up to 0.9985) and trace detection (2.7–3.4 ng mL−1). Relative standard deviation (RSD) values determined at different concentration levels ranged between 2.3 and 8.0%, and the screened sorbent shows excellent regeneration ability for four cycles. With this developed Ce-SBA-15 based stir bar-supported micro-solid-phase extraction, trace levels of nitrosamines can be detected in matrices that are commonly encountered by humans.
       
  • l-DOPA&rft.title=Arabian+Journal+of+Chemistry&rft.issn=1878-5352&rft.date=&rft.volume=">CuNPs decorated molecular imprinted polymer on MWCNT for the
           electrochemical detection of l-DOPA

    • Abstract: Publication date: Available online 22 June 2018Source: Arabian Journal of ChemistryAuthor(s): M.P. Sooraj, Archana S. Nair, Suresh C. Pillai, Steven J. Hinder, Beena Mathew A novel synthesis of copper nanoparticle (CuNPs) is carried out by the reduction of ethylene diamine Cu complexes using sodiumborohydride as reducing agent. The synthesized copper nanoparticle is grafted with molecular imprinted polymer on MWCNT (CuNPs/MWCNT-MIPs). Fabricated sorbent is used for the molecular recognition and sensing of levodopa (l-DOPA) in human urine and pharmaceutical samples. The non covalent interaction between l-DOPA and the functional groups present in the selective binding sites of the polymer composite sorbent is mainly responsible for the recognition property. The synthesis of CuNPs decorated MWCNT-MIPs and its extents are characterized by employing UV–Vis spectroscopy, Fourier-transform infrared spectroscopy, powder X-ray diffraction analysis, X-ray photoelectron spectroscopy, scanning electron microscopy and transmission electron microscopy techniques. The electrochemical investigation shows that the imprinted (CuNPs/MWCNT-MIP) material has good recognition capacity towards l-DOPA. The sensitivity is found to be directly proportional to the concentration of template with a detection limit of 7.23 × 10−9M (S/N = 3). The specificity and selectivity of the fabricated sensor give a fine discrimination between l-DOPA and structurally related compounds such as dopamine, uric acid, 3,4-Dihydroxyphenylacetic acid and homovanillic acid.
       
  • Application of carbon nanotubes in extraction and chromatographic
           analysis: A review

    • Abstract: Publication date: Available online 12 June 2018Source: Arabian Journal of ChemistryAuthor(s): Zeid Abdullah ALOthman, Saikh Mohammad Wabaidur Carbon nanotube (CNT), a well-known carbon-based nanomaterial has drawn much attention in many application fields including chemistry in the last few decades. Many researchers and scientists have shown huge interest to improve the extraction methodologies and adopt their applications in combination with chromatography technique. With respect to this, the exceptional applications of CNTs have been introduced as extraction sorbent due to their excellent inborn physical and chemical properties. In particular, CNTs have consistently been used as adsorbents in various techniques including solid-phase micro-extraction, solid-phase extraction, micro dispersive slid phase extraction, magnetic dispersive solid phase extraction, analytes enrichment, sample fractionation and clean-up as well as support for many derivatization reactions. Many research papers have discussed the successful use of CNTs to overcome the limitations of the extraction techniques due to their excellent sorbent capacity. In addition, considering the clear need to make chromatographic technique more successful, the applications of CNTs have been reported in the literatures in details as stationary and pseudo-stationary phases for the separation and extraction of challenging compounds. Because of the higher thermal and chemical stability, CNTs have been anticipated as stationary phase modifier for chromatographic applications to avoid bleeding of the columns and enable the analysis even at very high temperature (1200 °C). In liquid chromatography CNTs have primarily been used in combination with other packing materials (silica) and sometimes incorporated in a porous polymeric monolith. Therefore, the recent utilizations of CNTs as extraction materials and stationary phases have been illustrated in the current review and a table listing the details applications of CNTs in aforementioned field is provided as well. We believe that the review will help researcher to gain vast knowledge about application of carbon nanotubes in the field of separation chemistry.
       
  • Fabrication of new type of barium ferrite/copper oxide composite
           nanoparticles blended polyvinylchloride based heterogeneous ion exchange
           membrane

    • Abstract: Publication date: Available online 12 June 2018Source: Arabian Journal of ChemistryAuthor(s): S.M. Hosseini, N. Rafiei, A. Salabat, A. Ahmadi The current study focuses on the electrochemical, morphological and antibacterial characteristics of a new type of polyvinylchloride based cation exchange membrane modified by BaFe12O19/CuO composite nanoparticles. The used BaFe12O19/CuO composite nanoparticles were synthesized by chemical precipitation technique. The formation of BaFe12O19/CuO was characterized by Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM) and X-ray diffraction (XRD). SEM and scanning optical microscopy (SOM) images also showed relatively uniform structure for the prepared membranes. The membrane water uptake was enhanced up to 14.5% in presence of BaFe12O19/CuO composite nanoparticles. The membrane ion exchange capacity, membrane potential, transport number, surface charge density, permselectivity and ion permeability/flux were also improved sharply by increase of additive concentration up to 2 %wt and then showed decreasing trend by more BaFe12O19/CuO content ratio from 2 to 8 %wt . The membrane areal electrical resistance were decreased significantly from ∼24 to ∼5 (Ω.cm2) by using of BaFe12O19/CuO nanoparticles. Moreover, modified membranes demonstrated good ability to removal of E-coli bacteria.
       
  • Establishment of analytical method for quantification of anti-inflammatory
           agents co-nanoencapsulated and its application to physicochemical
           development and characterization of lipid-core nanocapsules

    • Abstract: Publication date: Available online 31 May 2018Source: Arabian Journal of ChemistryAuthor(s): Kelly Ayumi Nakama, Renata Bem dos Santos, Carlos Eduardo da Rosa Silva, Jessica Cristina Izoton, Anne Suely Pinto Savall, Maria Eduarda Ziani Gutirrez, Silvane Souza Roman, Cristiane Luchese, Simone Pinton, Sandra Elisa Haas Anti-inflammatory agents may be alternatives for the treatment of Alzheimer's disease. Then, we propose the nanotechnology as a strategy to curcumin and meloxicam co-nanoencapsulation for neurodegenerative diseases treatment. In this study, we developed and validated an analytical method by HPLC-DAD for simultaneous quantification of curcumin and meloxicam in the same formulation. We applied this method to characterize curcumin, meloxican and curcumin plus meloxican loaded lipid-core nanocapsules (LNC): drug content, encapsulation efficiency, photostability and drug's distribution. Additionally, toxicity levels of the nanoparticles were evaluated in vivo (mice). Therefore a C18-RP column was used with a guard column packed with the same material as the stationary phase. Acetonitrile: methanol: water: triethylamine (52:5:43:0.3 v/v/v/v), was used as the mobile phase in the 1 mL min−1 flow. Detection was 424 nm (curcumin) and 365 nm (meloxicam). The method was established in accordance with the current national and international guidelines, showing good linearity (r2 > 0.999). The formulations showed exclusively nanosized particles, negative zeta potential and slightly acidic pH, with content and encapsulation rate close to 100%. The distributions of meloxicam and curcumin in the LNC (alone or co-encapsulated) were type III and type VI, respectively. LNC were able to protect both drugs against UVA degradation. In vivo experiments showed no toxicity in relation to the parameters determined of all LNC evaluated in mice. In this work, we showed the possibility to carry meloxicam and curcumin in LNC with good technological characteristics and without toxicity in vivo with prospects for the treatment of Alzheimer's disease in sequential pharmacological studies.Graphical abstractGraphical abstract for this article
       
  • Optimization and detailed stability study on coupling of CdMoO4 into BaWO4
           for enhanced photodegradation and removal of organic contaminant

    • Abstract: Publication date: Available online 30 May 2018Source: Arabian Journal of ChemistryAuthor(s): Mohammad Eghbali-Arani, Saeid Pourmasoud, Farhad Ahmadi, Mehdi Rahimi-Nasrabadi, Vahid Ameri, Ali Sobhani-Nasab BaWO4 nanoparticles and BaWO4/CdMoO4 nanocomposites were synthesized by eco-friendly method at low temperature. The effects of various capping agents such as glucose, fructose, lactose, and starch on the morphology and particle size of BaWO4/CdMoO4 nanocomposites were investigated. The nanocluster was obtained with glucose and Ba2+ to capping agent molar ratio of (1:2). BaWO4/CdMoO4 nanocomposites were analyzed through techniques including, XRD, FT-IR, VSM, TEM, PL, FESEM, UV–vis, and EDX. According to the BET results, in the presence of glucose as the capping agent, surface area increased from 13.781 m2/g to 122.22 m2/g. Furthermore, adding CdMoO4 nanoparticles to BaWO4 causes optical properties and photocatalytic activity of BaWO4 to improve. Moreover, the effects of several factors such as BaWO4/CdMoO4 nanocomposites concentration and its particle size and difference dyes on the photocatalytic performance of BaWO4/CdMoO4 nanocomposites were studied under visible light.
       
  • Construction of High Efficient g-C3N4 Nanosheets combined with Bi2MoO6-Ag
           Photocatalysts for Visible-Light-Driven Photocatalytic Activity and
           inactivation’s of Bacteria’s

    • Abstract: Publication date: Available online 29 May 2018Source: Arabian Journal of ChemistryAuthor(s): Shanmugam Vignesh, Muppudathi Anna Lakshmi, J. Sridhar, Jeyaperumal Kalyana Sundar Novel g-C3N4-Bi2MoO6-Ag nanocomposite with their g-C3N4 nanosheets was synthesized by a facile hydrothermal method. The superior photocatalytic performance of gC3N4-Bi2MoO6-Ag nanocomposite was owing to the interface of Bi2MoO6/Ag nanomaterials whereas reduced the bandgap which enables high separation efficiency, suppressed recombination rate of charge carriers and their high specific surface area (97.4 cm3 g−1). For the MB dye degradation efficiency accomplishes 99.6% within 80 min under the visible light. Significantly, the ideal photocatalytic activity of gC3N4-Bi2MoO6-Ag composite has 3.63 times faster than pristine g-C3N4. Based on the trapping test, the superoxide radical O2•- and hydroxyl radical (OH.) plays a vital role in dye degradation in chief g-C3N4-Bi2MoO6-Ag nanocomposite under the visible light exposure. Novel gC3N4-Bi2MoO6-Ag catalyst has been exhibited superior electrochemical performance, which is smaller charge transfer resistance (impedance), and the prime photocurrent response has confirmed that more charge carrier abilities. The physicochemical assemblies and high degradation efficiencies were preserved after five successive cycles, whereas signifying that the sample was displayed good stability. Based on the consistent energy band positions, the probable mechanism for heightening photocatalytic activity was proposed. This study delivers a visible light driven novel g-C3N4-Bi2MoO6-Ag photocatalyst is a capable aspirant material and applicable for environmental remediation. Also, the antibacterial activity is well exposed towards disinfection of the bacterial strain, including pathogens which are S. aureus (G+) and E. coli (G-) bacteria’s.
       
  • Fabrication and characterization of supported dual acidic ionic liquids
           for polymer electrolyte membrane fuel cell applications

    • Abstract: Publication date: Available online 29 May 2018Source: Arabian Journal of ChemistryAuthor(s): Masoumeh Zakeri, Ebrahim Abouzari-Lotf, Mohamed Mahmoud Nasef, Arshad Ahmad, Mikio Miyake, Teo Ming Ting, Paveswari Sithambaranathan In this study, we proposed an innovative and versatile method for preparation of highly stable and conductive supported ionic liquid (IL) membranes for proton exchange fuel cell applications. Novel covalently supported dual acidic IL membranes were prepared by radiation induced grafting of 4-vinyl pyridine (4-VP) onto poly(ethylene-co-tetrafluoroethylene) (ETFE) film followed by post-functionalization via sequential treatments with 1,4-butane sultone and sulfuric acid to introduce pyridinium alkyl sulfonate/hydrogen sulfate moieties. The advantage of our approach lies in grafting polymers with highly reactive functional groups suitable for efficient post-sulfonation. The membranes displayed better swelling and mechanical properties compared to Nafion 112 despite having more than 3 times higher ion exchange capacity (IEC). The proton conductivity reached superior values to Nafion above 80 °C. Particularly, the membrane with ion exchange capacity of 3.41 displayed a proton conductivity of 259 mScm−1 at 95 °C. This desired conductivity value is attributed to the high IEC of the membranes as well as dissociation of the hydrophobic ETFE polymer and hydrophilic pyridinium alkyl sulfonate groups. Such appealing properties make the supported IL membranes promising for proton exchange membrane fuel cells (PEMFC).
       
  • Green synthesis of platinum nanoparticles using Saudi’s Dates extract
           and their usage on the cancer cell treatment

    • Abstract: Publication date: Available online 29 May 2018Source: Arabian Journal of ChemistryAuthor(s): Najlaa S. Al-Radadi Green synthesis of the Platinum nanoparticle of dates is carried out for examining their effect on various cancer cells. The extract solution of Dates (biodegradable surfactant) is used for this purpose. The bio-degradable plant-based surfactant, used in the study, occurs naturally, and no other reducing, or capping agent is used for cancer cell treatment. The aqueous extract solution of popular dates Ajwa and Barni acts as a stabilizing and reducing agent during the production of PtNPs at ambient condition because of simplicity, long-time stability, and cost-effectiveness. In order to achieve the best size and shape of nanoparticles, different ratio of extract and metal salt were mixed and developed. Additionally, nanoparticles of varying size were furnished by altering the pH of the reaction. Spectroscopic techniques like FTIR, X-ray Diffraction (XRD), EDX, thermos-gravimetric analysis (TGA), UV–vis, and transmission electron microscopy (TEM) were applied to identify PtNPs. In this study, electrochemical HPCL and high-performance liquid chromatography (HPCL) are combined for better understanding and effectiveness. The metabolites such as amino acid, sugar, organic acid, flavonoids, phenol, and minerals, in the Dates produced in Al-Madinah Al-Munawarah, have been analyzed with the help of the techniques employed in the study.PtNPs' anticancer activities were evaluated for different cancer cells including the colon carcinoma cells (HCT-116), breast cells (MCF-7), and hepatocellular carcinoma (HePG-2). Commonly used effective anticancer agent, Doxorubicin HCl, is used in the current study related to anticancer activitiy. To discover the antibacterial effect, antibacterial agents Ampicillin and Gentamicin are used. Lastly, the Gram-negative bacteria: Escherichia coli (RCMB 010052) and Gram-Positive Bacteria: Bacillus subtilis (RCMB 010067) were used to determine the antibacterial application of PtNPs.
       
  • Fluorinated phosphonate analogues of phenylalanine: Synthesis, X-ray and
           DFT studies

    • Abstract: Publication date: Available online 19 May 2018Source: Arabian Journal of ChemistryAuthor(s): Joanna Kwiczak-Yiğitbaşı, Jean-Luc Pirat, David Virieux, Jean-Noël Volle, Agnieszka Janiak, Marcin Hoffmann, Donata Pluskota-Karwatka Due to their biological activity and structural analogy to corresponding α-amino acids, α-aminophosphonates and their fluorinated derivatives provide an important source for drug discovery. Therefore convenient access to this class of compounds is still desirable. Four series of novel phosphonate analogues of fluorinated phenylalanine containing variable number of fluorine atoms in different positions of the phenyl ring were synthesized and subjected to solid state characterization by single-crystal X-ray diffraction analysis, and to studies with the use of NMR, HRMS and DFT methods. Such an approach provided valuable information in regard to preferable conformation, hydrogen bonds and also weak intermolecular interactions present in the crystals investigated. As analogues of naturally occurring compounds, the obtained α-aminophosphonates have a big potential for biological activity. Formation of some indolinylphosphonates as minor products arisen from intramolecular SNAr reactions show that aminophosphonates exhibiting an electronically depleted aromatic group, and possessing a fluorine atom in ortho position of the phosphonoalkyl substituent may give an entrance to further derivatives that may exhibit entirely new properties.Graphical abstractNovel fluorinated phosphonate analogues of phenylalanine were obtained and subjected to structural investigations by NMR, HRMS and DFT methods, and by single-crystal X-ray diffraction analyses. When aldehydes possessing a fluorine atom in ortho position of the methyleneformyl group were involved in the synthesis, 2-indolinylphosphonates were also formed. The synthesized phenylalanine analogues have a big potential for biological activity and are good substrate for SNAr reactions.Graphical abstract for this article
       
  • Synthesis of 2D boron nitride doped polyaniline hybrid nanocomposites for
           photocatalytic degradation of carcinogenic dyes from aqueous solution

    • Abstract: Publication date: Available online 19 May 2018Source: Arabian Journal of ChemistryAuthor(s): Syed Shahabuddin, Rashmin Khanam, Mohammad Khalid, Norazilawati Muhamad Sarih, Juan Joon Ching, Sharifah Mohamad, R. Saidur This investigation focused on the photocatalytic treatment of pollutants in waste water using methylene blue (MB) and methyl orange (MO) as the model dyes. In this study, conducting polyaniline (PANI) based nanocomposites doped with 2D hexagonal boron nitride (h-BN) were synthesised using simplistic oxidative in-situ polymerization technique by employing ammonium persulfate as an initiator in acidic medium. The synthesised 2D h-BN doped PANI nanocomposites were comprehensively characterized using field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), elemental mapping, X-ray diffraction (XRD), Brunauer-Emmett-Teller analysis (BET), thermogravimetric analysis (TGA), and Fourier transform infrared spectroscopy (FTIR). Degradation of MB and MO dyes under UV irradiations was performed to evaluate the photocatalytic performance of the synthesised nanocomposites. The results indicated that the h-BN nanosheets doped nanocomposites demonstrated better photocatalytic activities as compared to bare PANI or h-BN. Moreover, the nanocomposite P-BN-2, with 2 wt% of 2D h-BN nanosheets was found to be an optimal composition with 93% and 95% degradation efficiency for MB and MO within 90 min respectively.Graphical abstractGraphical abstract for this article
       
  • Insight on the structural aspect of ENR-50/TiO2 hybrid in KOH/C3H8O medium
           revealed by NMR spectroscopy

    • Abstract: Publication date: Available online 18 May 2018Source: Arabian Journal of ChemistryAuthor(s): Omar S. Dahham, Rosniza Hamzah, Mohamad Abu Bakar, Nik Noriman Zulkepli, Abdulkader M. Alakrach, Sung Ting Sam, Mohd Firdaus Omar, Tijjani Adam, Awad A. Al-rashdi The ring-opening reactions (ROR) of epoxide groups in epoxidized natural rubber/titania (ENR-50/TiO2) hybrid in potassium hydroxide/isopropanol medium were examined using NMR spectroscopy and supported by the FTIR technique. The thermal behaviour of the hybrid was also studied using TG/DTG and DSC analyses. The 1H NMR results suggested that 16.82% of ROR occurred in the hybrid, while the 13C NMR results exhibited five new peaks at δ 19.5, 71.0, 73.7, 91.7 and 94.4 ppm in the hybrid. 2D NMR, such as HMQC, HMBC and COSY techniques, further scrutinized these assignments. The FTIR spectrum exhibited Ti-O-C characteristics via the peak at 1028 cm−1. The TG/DTG results showed four steps of thermal degradation at 44–148, 219–309, 331–489 and 629–810 °C due to the existence of Ti moieties along with a polymer chain mixture (intact and ring-opened epoxide groups) of ENR-50, which in turn led to an increase in the Tg value of the hybrid to 27 °C compared to that of purified ENR-50 at −17.72 °C.
       
  • Cr(II)-promoted internal cyclization of acyclic enediynes fused to
           benzo[b]thiophene core: Macrocycles versus 2-methylenecycloalkan-1-ols
           formation

    • Abstract: Publication date: Available online 18 May 2018Source: Arabian Journal of ChemistryAuthor(s): A.E. Kulyashova, A.V. Ponomarev, S.I. Selivanov, A.F. Khlebnikov, V.V. Popik, I.A. Balova The utility of the intramolecular Nozaki-type coupling for the synthesis of macrocyclic benzo[b]thiophene-fused enediynes has been explored. The starting acyclic enediynes were prepared by the iodocyclization of 2-(buta-1,3-diynyl)thioanisoles followed by the Sonogashira cross-coupling of the resulting iodo-substituted benzo[b]thiophene with corresponding acetylenes. We found that Cr(II)-promoted intramolecular cyclization of 7-[2-(iodoethynyl)benzo[b]thiophen-3-yl]hept-6-ynal and 7-[3-(iodoethynyl)benzo-[b]thiophen-2-yl]hept-6-ynal resulted in the formation of 11-membered macrocyclic enediynes, while both expected 10-membered enediynes cannot be produced under the Nozaki-type reaction from corresponding 6-[3-(iodoethynyl)benzo[b]thiophen-2-yl]hex-5-ynal and 6-[2-(iodoethynyl)benzo[b]thiophen-3-yl]hex-5-ynal. In the case the reaction was catalyzed by Ni(II), the attack on a proximal triple bond led to the formation of 2-methylenecycloalkane-1-ol fragments, instead of macrocyclization. The DFT analysis of the ring strain in the benzo[b]thiophene-fused 10- and 11-membered enediyne-containing cycle provides the plausible explanation of the observed regioselectivity.
       
  • Incorporating MoFe alloys into reduced graphene oxide as counter electrode
           catalysts for dye-sensitized solar cells

    • Abstract: Publication date: Available online 18 May 2018Source: Arabian Journal of ChemistryAuthor(s): Sangho Shin, Van-Duong Dao, Ho-Suk Choi In this study, MoFe alloy decorated onto reduced graphene oxide (RGO) nanohybrids is successfully synthesized with various volume ratios of Fe to Mo precursors using a dry plasma reduction method at a low temperature and under atmospheric pressure and is introduced for the first time as an electrocatalyst for counter electrodes (CEs) in dye-sensitized solar cells (DSCs). As observed by HRSEM and TEM analyses, MoFe is successfully immobilized on a 3D network structure of RGO. Well-dispersed MoxFe1−x (0 ≤ x ≤ 1) NPs ranging in size from 2 to 6 nm are stabilized with RGO after co-reduction of the metal precursor ions and graphene oxide. The developed catalysts are then applied as CEs in DSCs. As a result, the Mo0.7Fe0.3/RGO nanohybrid exhibited the highest electrocatalytic activity, corresponding to the lowest charge transfer resistance of 0.11 Ω, among the electrodes tested. The DSC employing Mo0.7Fe0.3/RGO CEs exhibits 5.44% efficiency, which is higher than the 1.26, 4.54 and 4.53% efficiency rates for cells using RGO, Mo0Fe1/RGO and Mo1Fe0/RGO electrodes, respectively, due to the optimization of the catalytic activity and the electron conductivity of the developed materials. Note that the efficiency of the device using a Pt electrode was 5.36% under identical conditions. This study concludes that the CE based on the MoFe/RGO nanohybrid is a prospective substitute for Pt which can provide new opportunities for advancing high-efficiency DSCs. Furthermore, the developed catalysts can be applied to other applications, such as methanol oxidation and oxygen reduction reactions.
       
  • Preparation and characterization of inexpensive kaolin hollow fibre
           membrane (KHFM) prepared using phase inversion/sintering technique for the
           efficient separation of real oily wastewater

    • Abstract: Publication date: Available online 15 May 2018Source: Arabian Journal of ChemistryAuthor(s): Siti Khadijah Hubadillah, Mohd Hafiz Dzarfan Othman, Mukhlis A. Rahman, A.F. Ismail, Juhana Jaafar A low-cost kaolin hollow fiber membrane (KHFM) with unique finger-like and sponge-like structures was successfully fabricated by utilizing cheap and abundantly available kaolin clay as the starting material via phase inversion/sintering technique. In this study, mixing kaolin particles prepare the ceramic suspension, dispersant, polymer binder, and solvent using a planetary ball mill. This process is then followed by extrusion at various kaolin contents, bore fluid flow rates, and sintering temperatures ranging from 1200 to 1500 °C. The effect of calcium carbonate (CaCO3) content and polyethylene glycol (PEG) molecular weight as a function of pore agents are also discussed. Membrane characterizations were performed in terms of morphology, pore size distribution, porosity, mechanical strength, contact angle value, and pure water flux. The performance of membranes towards oil-in-water separation was conducted using oily wastewater samples taken from three points in Johor, Malaysia which were Kluang Oil Palm Mill Sdn. Bhd. in Kluang district, a car wash in Taman Skudai Baru in Johor Bahru district, and Meranti café, Universiti Teknologi Malaysia (UTM). The optimum parameters in fabricating the inexpensive KHFM were identified. It was found that the increase of kaolin content, bore fluid flow rate, and sintering temperature gave insignificant effect in the formation of finger–like structure but the process can be used to find a defect-free (i.e., rounded lumen and sufficient thickness) hollow fiber membrane shape. Interestingly, the finger-like structure can be controlled by the addition of PEG as a pore agent at different molecular weights. KHFM prepared with PEG 30,000 as a pore agent offered the highest oil rejection of 99.99% of turbidity and total organic carbon (TOC), and 91.8% of chemical oxygen demand (COD) with stable high flux of 320 L/m2h for all oily wastewater samples.Graphical abstractGraphical abstract for this article
       
  • Selective conversion of stearic acid into high-added value octadecanedioic
           acid using air and transition metal acetate bromide catalyst: Kinetics,
           pathway and process optimization

    • Abstract: Publication date: Available online 15 May 2018Source: Arabian Journal of ChemistryAuthor(s): Nazmun Sultana, Chandan Guria, Vinod K. Saxena Liquid phase selective homogeneous catalytic oxidation of stearic acid (SA) was carried out to obtain industrially important carbon neutral high-added value octadecanedioic acid (ODDA). The oxidation was carried using air, cobalt(II)-acetate, manganese(II)-acetate and HBr catalyst in acetic acid (AcOH) solvent at an elevated temperature and pressure. SA oxidation products were analyzed by gas chromatography–mass spectrometry (GC–MS), gas chromatography (GC) and CO2 analyzer, and SA was oxidized selectively to ODDA without producing CO2 and intermediates like alcohols, aldehydes and ketones. The effect of SA loading (5–20%), pressure (2.8–5.8 barg) and temperature (353–383 K) on ODDA yield was studied by varying one variable at a time. Central composite design assisted response surface methodology was employed to find (i) the optimal design of experiments involving several combination of cobalt(II)-acetate (Co: 0–700 ppm), manganese(II)-acetate (Mn: 0–700 ppm) and HBr (Br–: 0–1144 ppm) and (ii) the most influencing variable and interaction among the variables. The synergistic effect of cobalt(II)-acetate in presence of HBr was observed and suggested that SA oxidation proceeds via bromine-bromide cycle. The elevated temperature and pressure along with reduced SA loading enhanced the yield of ODDA. The maximum ODDA yield was found to be 90.5% and corresponding optimum cobalt (II), manganese (II) and bromide concentration were 600.4, 452.2 and 1016.6 ppm, respectively, at fixed SA:AcOH-10:90, pressure-2.8 barg and temperature-383 K. Finally, SA oxidation kinetic analysis was determined based on the pseudo-first order homogeneous catalysis and found to be kinetically controlled with an average activation energy 34.55 kJ mol−1. The proposed kinetic model fitted well with the time-variant experimental SA and ODDA concentration under varying operating condition with percent average absolute deviation less than 5.0%.
       
  • Effects of a dianion compound as a surface modifier on the back reaction
           of photogenerated electrons in TiO2-based solar cells

    • Abstract: Publication date: Available online 7 May 2018Source: Arabian Journal of ChemistryAuthor(s): Ji Young Kim, Ki Hong Kim, Dae-Hwan Kim, Yoon Soo Han The TiO2 films were modified with a dianion compound, 1,2-ethanedisulfonic acid disodium salt (ESD), to give a negative charge (ethane sulfonate anion) on the TiO2 surface, i.e., TiO2-O-SO2-CH2-CH2-SO3-), and effects of repulsion between the negative charge and ions (I3−) of the electrolyte on the performance of dye-sensitized solar cells (DSSCs) were investigated. The reference device without any modification showed a power conversion efficiency (PCE) of 9.89%, whereas for the device with ESD(20)-TiO2/FTO, which was prepared by soaking bare TiO2/FTO in an ESD solution for 20 min, the PCE was increased to 10.97%, due to an increase in both short-circuit current (Jsc) and open-circuit voltage(Voc). It was verified from the measurements of electrochemical impedance, open-circuit voltage decay and dark current that the enhancement in the Jsc and Voc values was attributed to the reduced back reaction between photoinjected electrons and I3− ions, resulting from the presence of the ethane sulfonate anions on the TiO2 surface.
       
  • Influence of the surfactant degree of oligomerization on the formation of
           cyclodextrin:surfactant inclusion complexes

    • Abstract: Publication date: Available online 5 May 2018Source: Arabian Journal of ChemistryAuthor(s): Victoria Isabel Martín, Pilar López-Cornejo, Manuel López-López, Daniel Blanco-Arévalo, Antonio José Moreno-Vargas, Manuel Angulo, André Laschewsky, María Luisa Moyá Supramolecular complexation is an attractive strategy to modulate the performance of surfactants, e.g., by host-guest interactions. Here, we investigate the interaction of single-chained, di-, tri-, and tetrameric cationic surfactants with cyclodextrins by conductivity and 1H NMR measurements, exploring the effect of increasing the number of the surfactant hydrophobic tails on the stability of cyclodextrin:surfactant inclusion complexes. The stoichiometry and the binding equilibrium constants of the different inclusion complexes were elucidated. Under the working conditions, the number of hydrophobic chains was found not to affect stoichiometry and 1:1 inclusion complexes were formed for all the surfactants investigated. The stability of the host-guest complexes decreases from single-chained to dimeric (“gemini”) surfactants, the binding following a non-cooperative mechanism. This result may be rationalized by taking into account steric constraints and electrostatic effects as well as the need to overcome the hydrophobic interactions between the chains of the same surfactant molecule. However, a further increase in the number of hydrophobic tails, from two to three to four, results in an increase in the equilibrium binding constant, K1. In this case, an increment in the number of chains capable of interaction with the cyclodextrin molecules seems to be the main factor responsible for the increase in K1. ROESY spectra show the coexistence of different types of 1:1 host-guest complexes for tri- and tetrameric surfactants.Graphical abstractThe surfactant degree of oligomerization affects the inclusion complex formationGraphical abstract for this article
       
  • Effect of functionalization of iron oxide nanoparticles on the physical
           properties of poly (aniline-co-pyrrole) based nanocomposites: Experimental
           and theoretical studies

    • Abstract: Publication date: Available online 4 May 2018Source: Arabian Journal of ChemistryAuthor(s): Ehsan Nazarzadeh Zare, Tahereh Abdollahi, Ahmad Motahari Poly(aniline-co-pyrrole)@functionalized Fe3O4 (PACP@f-Fe3O4) nanocomposites were prepared by a two-step method. In the first step, the Fe3O4-OH and Fe3O4-NH2 nanoparticles were synthesized by the solvothermal and co-precipitation techniques, respectively. In the second step, the PACP@f-Fe3O4 nanocomposites were synthesized by an in-situ microemulsion polymerization technique. The synthesized materials were characterized by Fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). Based on the SEM, the iron oxide changed the morphology of the PACP copolymer from being completely nanospheres. The TGA showed the higher thermal stability of the PACP@Fe3O4-OH nanocomposite in comparison to the PACP@Fe3O4-NH2, and the density functional theory (DFT) successfully confirmed this fact by calculating the binding energies between the PACP copolymer and functionalized nanoparticles. Also, the HOMO − LUMO energy gap (Eg) values were determined by the DFT to investigate the electrical conductivities, which are in accord with the experimental electrical conductivities in the order PACP@Fe3O4-OH > PACP@Fe3O4-NH2 > PACP.
       
  • Microwave-assisted intermolecular aldol condensation: Efficient one-step
           synthesis of 3-acetyl isocoumarin and optimization of different reaction
           conditions

    • Abstract: Publication date: May 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 4Author(s): Murat Koca, Ali S. Ertürk, Adil Umaz This paper describes the optimization and comparison of conventional and microwave-assisted methods for efficient, cheap, one-pot, and straightforward synthesis of isocoumarins under mild reaction conditions. On this basis of this aim, synthesis of 3-acetyl isocoumarin from 2-formylbenzoic acid with mono-chloroacetone was chosen as a model reaction. Afterward, four different methods conventional (Method A), microwave open vessel (Method B), microwave sealed vessel (Method C), and microwave closed system (Method D) were used methodologically to determine best experimental conditions for each of these methods in this model reaction. The results revealed that developed Methods A, C and D could be used successfully under solvent-free conditions with good yields (84–87%) for the future efficient, one-pot synthesis of isocoumarins. This paper is also a first for characterizing 3-acetyl isocoumarin by using ATR, 1H NMR, 13C NMR and GC–MS.
       
  • Synthesis and antioxidant study of new polyphenolic hybrid-coumarins

    • Abstract: Publication date: May 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 4Author(s): Karina Pérez-Cruz, Mauricio Moncada-Basualto, Javier Morales-Valenzuela, Germán Barriga-González, Patricio Navarrete-Encina, Luis Núñez-Vergara, J.A. Squella, Claudio Olea-Azar The antioxidant capacity of hydroxylated coumarins and hydroxybenzoic acids has been widely described. However, there is little information on the antioxidant activity when both systems are functionalized. In this work, new hybrid compounds synthesis with a common coumarin scaffold and hydroxybenzoic acids is described. Their antioxidant capacity was evaluated against reactive oxygen species (ROS) using oxygen radical absorbance capacity-fluorescein (ORAC-FL), electron spin resonance (ESR) spin trapping, quenching of superoxide anion, cellular antioxidant activity (CAA) and a ferric reducing ability of plasma (FRAP assay). Additionally, the local reactivity indicator (Fukui index) was calculated to discriminate different reactive sites in the new molecules in which the oxidative process occurs. Likewise, the BDE values were calculated in order to obtain information about the antioxidant capacity for HAT mechanisms. The insertion of organic phenols in a simple coumarin structure produced new derivatives with an improved antioxidant capacity in relation to coumarin 1a. For compound 3c, a synergy phenomenon in ORAC-FL and the FRAP test was observed. For compound 3b, this phenomenon was observed in the superoxide scavenging test. According to the CAA assay results, the activity of the new compounds is limited to those oxidative processes in lipophilic media (e.g., bio membranes).Graphical abstractGraphical abstract for this article
       
  • Winter wild fennel leaves as a source of anti-inflammatory and antioxidant
           polyphenols

    • Abstract: Publication date: May 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 4Author(s): Severina Pacifico, Silvia Galasso, Simona Piccolella, Nadine Kretschmer, San-Po Pan, Paola Nocera, Annamaria Lettieri, Rudolf Bauer, Pietro Monaco In the course of a screening program on the seasonal phenol composition of wild Mediterranean medicinal and aromatic plants, broadly used for culinary purposes, Foeniculum vulgare Mill. was the focus of the present study. Hydroalcoholic extracts from fennel freeze-dried leaves, collected in different seasons along 2012 and 2013 years, were quali-quantitatively analyzed through LC/MS/MS techniques. Winter extract contained, beyond several hydroxycinnamoyl quinic acids and flavonol glycosides, two chromone derivatives. Flavonol hexuronides were the main spring sample constituents. Phenol profile differences among the extracts influenced massively their bioactivity. When the antioxidant screening was performed, winter extract effectively scavenged DPPH and ABTS+ and reduced Fe3+. Although all the extracts did not show cytotoxicity, they were differently able to exert cytoprotection in H2O2-oxidized cell systems and to affect COX-2 gene expression in THP-1 cells. The most active one was winter extract, which inhibited COX-2 expression by 40%, whereas spring sample showed a weak pro-inflammatory capability.
       
  • Synergism of thiocyanate ions and microinterfacial surface as driving
           forces for heavy multi-metals extraction

    • Abstract: Publication date: May 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 4Author(s): Daniela Cadar, Nicoleta Liliana Olteanu, Elena Adina Andrei, Adina Roxana Petcu, Cosmina Andreea Marin, Aurelia Meghea, Maria Mihaly A comprehensive study has been carried out to evaluate the extraction of heavy metals mixture (Co2+, Cr3+, Cu2+, Ni2+) from aqueous media by Winsor II non-ionic microemulsion, containing polyoxyethylene (4) lauryl ether as non-ionic surfactant and butyl acetate as organic phase. The extraction mechanism is based on the formation of thiocyanate complexes of metals and their transfer from aqueous to microemulsion phase, either towards the interfacial film of surfactant (Co2+) or into the core of micelles (Cr3+, Cu2+, Ni2+). The value of the distribution coefficient for Co2+ was higher than for the other studied metals and its extraction efficiency was not dependent on the working conditions, showing a maximum value (99.99%) in all cases. By using successive extractions, chromium, nickel and copper ions that remained in the aqueous phase after first extraction were transported into the microemulsion phase, leading to an increase in the extraction efficiency up to 99.99% for chromium and copper, and 85% for nickel. Based on pH influence, a selective extraction of Co2+ and Cr3+ can be achieved, since the cobalt ions were completely extracted into the microemulsion phase at pH = 1, and the chromium ions still remained in the aqueous phase.
       
  • Inside Front Cover - Editorial Board

    • Abstract: Publication date: May 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 4Author(s):
       
  • Validated electroanalytical determination of flavoxate hydrochloride and
           tolterodine tartrate drugs in bulk, dosage forms and urine using modified
           carbon paste electrodes

    • Abstract: Publication date: May 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 4Author(s): Ali K. Attia, Eman Y.Z. Frag, Heba E. Ahmed Simple, precise, inexpensive and sensitive voltammetric methods have been developed for the determination of flavoxate HCl (FLXHC) and tolterodine tartrate (TOLT) in the bulk, pharmaceutical dosage forms and human urine using ferrocene modified carbon paste electrode (FMCPE) for FLXHC and polyethylene glycol modified carbon paste electrode (PEGMCPE) for TOLT. The electrochemical behavior of FLXHC and TOLT showed irreversible diffusion-controlled oxidation processes in Britton-Robinson (BR) buffer over the entire pH range from 2 to 6 for FLXHC and from 2 to 9 for TOLT. The peak current was evaluated as a function of some variables such as pH, scan rate and number of cycles of ferrocenium solution and PEG concentration. The linear ranges were 7.8 × 10−6–1.2 × 10−4 mol L−1 and 7.6 × 10−7–2.2 × 10−4 mol L−1 for FLXHC and TOLT, respectively. The limits of detection and quantification were 5.9 × 10−7 and 2 × 10−6 for FLXHC and 8.6 × 10−8 mol L−1 and 2.9 × 10−7 mol L−1 for TOLT. The percentage recoveries were found in the following ranges: 99.2–101.1% and 99.7–101.1% for FLXHC and TOLT, respectively.Graphical Graphical abstract for this article
       
  • A facile designed highly moderate craspedia flowerlike sulphated Bi2O3-fly
           ash catalyst: Green synthetic strategy for
           (6H-pyrido[3,2-b]carbazol-4-yl)aniline derivatives in water

    • Abstract: Publication date: May 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 4Author(s): Kannan Thirumurthy, Ganesamoorthy Thirunarayanan The air pollutant fly ash was facile designed as a green catalyst and practical to organic synthesis. We have designed sulfated Bi2O3-fly ash catalyst (12 wt%) and it was characterized by Fourier transform infrared (FT-IR), confocal Raman, Powder X-ray diffraction (XRD), Field emission electron microscopy (FE-SEM), elemental color mapping, energy-dispersive X-ray spectroscopy (EDS), Transmission electron microscopy (TEM) and Brunauer–Emmett–Teller (BET) techniques. The sulfated Bi2O3-fly ash was found an excellent catalytic application for the synthesis of (6H-pyrido[3,2-b]carbazol-4-yl)aniline derivatives in water has been described. The synthesized (6H-pyrido[3,2-b]carbazol-4-yl)aniline derivatives were confirmed by spectral techniques Fourier transform infrared (FT-IR), Nuclear magnetic resonance (NMR) and Liquid chromatography–mass spectrometry (LC–MS). The significant catalytic role of Bi–N interaction was readily form adduct, moreover Bi–O bond was favorable for hydrogen abstraction, dehydration and aromatization. Due to the strong potential, the precise reaction time and high yield have been achieved, which is realized from hot filtration test. The sulfated Bi2O3-fly ash catalyst could be reused for five successive run, the resulting in no appreciable change in the catalytic activity. The crystal phase and surface morphology of fifth run catalyst were examined by powder XRD, FE-SEM, EDS and TEM techniques, and the results revealed no changes in catalyst nature. The sulfated Bi2O3-fly ash catalyst has high efficiency, reusability, good catalytic activity, environmentally harmless and notable potential in industrial applications.Graphical abstractGraphical abstract for this article
       
  • Cyclic voltammetry, square wave voltammetry, electrochemical impedance
           spectroscopy and colorimetric method for hydrogen peroxide detection based
           on chitosan/silver nanocomposite

    • Abstract: Publication date: May 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 4Author(s): Hoang V. Tran, Chinh D. Huynh, Hanh V. Tran, Benoit Piro In this paper, we demonstrate a promising method to fabricate a non-enzymatic stable, highly sensitive and selective hydrogen peroxide sensor based on a chitosan/silver nanoparticles (CS/AgNPs) hybrid. Using this composite, we elaborated both electrochemical and colorimetric sensors for hydrogen peroxide detection. The colorimetric sensor is based on a homogenous reaction which fades the color of CS/AgNPs solutions from red-orange to colorless depending on hydrogen peroxide concentration. For the electrochemical sensor, CS/AgNPs were immobilized on glassy carbon electrodes and hydrogen peroxide was measured using cyclic voltammetry, square wave voltammetry and electrochemical impedance spectroscopy. The response time is less than 10 s and the detection limit is 5 μM.
       
  • Facile LaOF: Sm3+ based labeling agent and their applications in residue
           chemistry of latent fingerprint and cheiloscopy under UV–visible light

    • Abstract: Publication date: May 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 4Author(s): C. Suresh, H. Nagabhushana, G.P. Darshan, R.B. Basavaraj, D. Kavyashree, S.C. Sharma, A. Arulmozhi, B. Daruka Prasad, H.J. Amith Yadav Luminescent lanthanum oxyfluoride nano inorganic materials were considered to be prospective building blocks for multifunctional applications. This offers new potentials in surface-based science comprising of visualization of latent fingerprint (LFPs) and lips print on non-porous surfaces. Traditional visualization techniques possess high backward hindrance, low sensitivity, complicated setup and poor visibility. To overcome with these problems, LaOF:Sm3+ (5 mol%) nanopowder (NPs) prepared via sonochemical route were explored. Photoluminescence (PL) emission spectra exhibit strong emission peaks at ∼566 nm, 607 nm, 653 nm and 708 nm attributed to 4G5/2 → 6H5/2, 4G5/2 → 4H7/2, 4G5/2 → 6H9/2 and 4G5/2 → 6H11/2 intra-4f orbital transitions of Sm3+ ions respectively. Estimated photometric properties confirm that the material emits warm orange red color. Therefore, the synthesized phosphor materials may quite be useful for LFPs recovery, cheiloscopy and optoelectronics applications.Graphical abstractGraphical abstract for this article
       
  • Influence of operational parameters on photocatalytic amitrole degradation
           using nickel organic xerogel under UV irradiation

    • Abstract: Publication date: May 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 4Author(s): Miguel A. Álvarez, Francisco Orellana-García, M. Victoria López-Ramón, José Rivera-Utrilla, Manuel Sánchez-Polo The objectives of this study were to analyze the influence of different operational variables and to determine the time course of total organic carbon (TOC) and medium toxicity during amitrole (AMT) photodegradation in the presence of Ni xerogel (X-Ni) as photocatalyst. A further study objective was to analyze the influence of the type of water on the photodegradation process. Results show that the degradation rate is directly proportional to the initial X-Ni concentration up to a maximum of 250 mg/L with a slight decrease thereafter, indicating progressive photon absorption saturation of the catalyst for a given incident radiation flow. At concentrations close to 250 mg/L X-Ni, the AMT photodegradation rate is not affected by further increases in X-Ni concentration. In addition, AMT photolysis is highly pH-dependent and is generally favored at pH values at which AMT is in its ionic form. The increase observed in AMT degradation rate under alkaline conditions can be attributed to the higher generation of HO radicals. The presence of chloride reduces the AMT degradation rate, because Cl− anions behave as h+ and HO radical scavengers. The degradation rate is also decreased by addition to the medium of organic matter, which acts as a filter. The behavior of TOC removal kinetics during AMT degradation in the presence of X-Ni is similar to that observed for AMT degradation kinetics. Finally, we highlight that photocatalysis is more effective in ultrapure water than in wastewater or tap water. In all systems, the optimal catalyst concentration is 250 mg/L. The medium toxicity increases with longer treatment time, indicating the formation of by-products that are smaller than AMT and can more readily penetrate the cell.
       
  • A theoretical assessment of antioxidant capacity of flavonoids by means of
           local hyper–softness

    • Abstract: Publication date: May 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 4Author(s): Claudia Sandoval-Yañez, Carolina Mascayano, Jorge I. Martínez-Araya A theoretical reactivity descriptor to estimate local reactivity on molecules was tested to assess the antioxidant capability of some flavonoids. It was validated by comparison with experimental precedents published already by Firuzi et al. (2005). The aforementioned reactivity index is called local hyper-softness (LHS). This parameter was applied on HO- substituent groups on the same set of flavonoids within each subclassification: flavones (apigenin and baicalein), flavonols (fisetin, galangin, 3–OH flavone, kaempferol, myricetin, and quercetin), flavanones (hesperetin, naringenin, taxifolin) and isoflavones (daidzein and genistein). Experimental values of both techniques, ferric reducing antioxidant power (FRAP) and anodic oxidation potential (Eap) were retrieved from Firuzi et al. (2005) with the purpose of validating the calculated LHS values. Excepting myricetin, the LHS values of all these compounds matched in a similar order relationship experimentally obtained by means of Eap and FRAP from Firuzi et al. (2005). Our results revealed that LHS is a suitable theoretical parameter to get an insight concerning to the antioxidant capacity of these compounds, in particular, LHS allows explaining experimentally obtained values of FRAP along with Eap values in terms of reactivity of HO- substituent groups belonging these molecules theoretically computed without including experimental parametes.
       
  • Design, synthesis and biological evaluation of new substituted
           5-benzylideno-2-adamantylthiazol[3,2-b][1,2,4]triazol-6(5H)ones.
           Pharmacophore models for antifungal activity

    • Abstract: Publication date: May 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 4Author(s): C. Tratrat, M. Haroun, A. Paparisva, A. Geronikaki, Ch. Kamoutsis, A. Ćirić, J. Glamočlija, M. Soković, Ch. Fotakis, P. Zoumpoulakis, Shome S. Bhunia, Anil K. Saxena As a part of our ongoing studies in developing new derivatives as antimicrobial agents we describe the synthesis of novel substituted 5-benzylideno-2-adamantylthiazol[3,2-b][1,2,4]triazol-6(5H)ones.The twenty-five newly synthesized compounds were tested for their antimicrobial and antifungal activity. All compounds have shown antibacterial properties with compounds 1–9 showing the lowest activity, followed by compounds 10–14 while compounds 15–25 the highest antibacterial activity. Specific compounds appeared to be more active than ampicillin in most studied strains and in some cases more active than streptomycin. Antifungal activity in most cases also was better than that of reference drugs ketoconazole and bifonazole. Elucidating the relation of molecular properties to antimicrobial activity as well as generation of pharmacophore model for antifungal activity of two fungal species Aspergillus fumigatus and Candida albicans were performed.
       
  • Production of biodegradable plastic from agricultural wastes

    • Abstract: Publication date: May 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 4Author(s): N.A. Mostafa, Awatef A. Farag, Hala M. Abo-dief, Aghareed M. Tayeb Agricultural residues management is considered to be a vital strategy in order to accomplish resource conservation and to maintain the quality of the environment. In recent years, biofibers have attracted increasing interest due to their wide applications in food packaging and in the biomedical sciences. These eco-friendly polymers reduce rapidly and replace the usage of the petroleum-based synthetic polymers due to their safety, low production costs, and biodegradability. This paper reports an efficient method for the production of the cellulose acetate biofiber from flax fibers and cotton linters. The used process satisfied a yield of 81% and 54% for flax fibers and cotton linters respectively (based on the weight of the cellulosic residue used). The structure of the produced bioplastic was confirmed by X-ray diffraction, FT-IR and gel permeation chromatography. Moreover, this new biopolymer is biodegradable and is not affected by acid or salt treatment but is alkali labile. A comparison test showed that the produced cellulose acetate was affected by acids to a lesser extent than polypropylene and polystyrene. Therefore, this new cellulose acetate bioplastics can be applied in both the food industry and medicine.
       
  • Free fluoride determination in honey by ion-specific electrode
           potentiometry: Method assessment, validation and application to real
           unifloral samples

    • Abstract: Publication date: May 2018Source: Arabian Journal of Chemistry, Volume 11, Issue 4Author(s): Nadia Spano, Valentina Guccini, Marco Ciulu, Ignazio Floris, Valeria M. Nurchi, Angelo Panzanelli, Maria I. Pilo, Gavino Sanna Surprisingly, a reliable method for measuring the concentration of free fluoride ions in honey is still missing from the literature, notwithstanding the generally recognized importance of the analyte and the matrix. To fill this gap, this study proposes and validates a straightforward ion-specific electrode potentiometric method for this task. The method offers very low detection and quantification limits (6.7 μg kg−1 and 25 μg kg−1, respectively), good linearity (R2 > 0.994), good sensitivity (typically 55 ± 3 mV for an order of magnitude of concentration) in an unusually low concentration interval (between 0.020 and 1 mg L−1), and acceptable precision and bias. The method was applied to 30 unifloral (thistle, eucalyptus and strawberry tree) honey samples from Sardinia, Italy. The amount of free fluoride ions found in these honeys appears to be lower than the range usually found in the literature; indeed, early results suggest a possible dependence of the analyte concentration on the honey’s botanical origin.
       
  • Synthesis of CeO2 doped ZnO nanoparticles and their application in
           Zn-composite coating on mild steel

    • Abstract: Publication date: Available online 27 April 2018Source: Arabian Journal of ChemistryAuthor(s): Deepa Kallappa, Venkatesha Thimmappa Venkatarangaiah CeO2 doped ZnO nanoparticles were synthesized by co-precipitation method and their size, structure and composition were characterized by XRD, SEM and EDAX analysis. The nanoparticles were used for generation of Zn-CeO2 doped ZnO composite (Zn-composite) coating on mild steel by electroplating. The surface morphology, elemental composition of Zn coated and Zn-composite coated samples were examined by scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDAX) respectively. Corrosion experiments were carried out by electrochemical techniques such as OCP, Tafel polarization, Anodic polarization and electrochemical impedance spectroscopy. The electrochemical corrosion behavior of Zn-composite coating was compared with pure zinc coating. The morphology of the deposits after corrosion tests was analyzed by SEM images. Incorporation of CeO2 doped ZnO nanoparticles into Zn-matrix significantly improved the corrosion resistance property of Zn-coating.
       
  • Green biosynthesis of superparamagnetic magnetite Fe3O4 nanoparticles and
           biomedical applications in targeted anticancer drug delivery system: A
           review

    • Abstract: Publication date: Available online 26 April 2018Source: Arabian Journal of ChemistryAuthor(s): Yen Pin Yew, Kamyar Shameli, Mikio Miyake, Nurul Bahiyah Bt Ahmad Khairudin, Shaza Eva Bt Mohamad, Takeru Naiki, Kar Xin Lee This review discussed about the green biosynthesis of magnetite nanoparticles (Fe3O4-NPs) and the biomedical applications, which mainly focus on the targeted anticancer drug delivery. Fe3O4-NPs have been studied and proved that Fe3O4-NPs can be used in various fields of application, due to “superparamagnetic” property that Fe3O4-NPs possessed. In targeted drug delivery system, drug loaded Fe3O4-NPs can accumulate at the tumor site by the aid of external magnetic field. This can increase the effectiveness of drug release to the tumor site and vanquish cancer cells without harming healthy cells. In order to apply Fe3O4-NPs in human body, Fe3O4-NPs have to be biocompatible and biodegradable to minimize the toxicity. So, green biosynthesis plays a crucial role as the biosynthesized Fe3O4-NPs is safe to be consumed by human because the materials used are from biological routes, such as plant extract and natural polymer. However, biosynthesis using plant extract is the most popular among them all as plant extract can act as both reducing and stabilizing agents in the synthesizing process of nanoparticles. This approach is not merely simple, yet economic and less waste production, which is environmental friendly. Several biomedical applications of Fe3O4-NPs are included in this review, but anticancer drug delivery study is discussed in detail. The criteria for Fe3O4-NPs to be used as drug delivery vehicle are discussed so as to study the optimum condition of Fe3O4-NPs in drug delivery application. Many researches showed the promising results of Fe3O4-NPs in treating cancer cells via in vitro study. Hence, this review is significant which summarize the vital points of Fe3O4-NPs in targeted anticancer drug delivery system. Conclusions have been made according to the literature reviewed and some points of view were proposed for future study.
       
  • Supramolecular drug inclusion complex of Capecitabine with cucurbit[7]uril
           and inverted cucurbit[7]uril

    • Abstract: Publication date: Available online 25 April 2018Source: Arabian Journal of ChemistryAuthor(s): Hai-Yan Wang, Yang Zhou, Ji-Hong Lu, Qing-Yun Liu, Gui-Ying Chen, Zhu Tao, Xin Xiao The interaction of capecitabine (CAP) with cucurbit[7]uril (Q[7]) and inverted cucurbit[7]uril (iQ[7]) was investigated using nuclear magnetic resonance, fluorescence spectroscopy, MALDI-TOF mass spectrometry and isothermal titration calorimetry. The obtained results revealed that the alkyl chain of CAP is located inside the cavities of Q[7] or iQ[7], whereas the other section of CAP remains outside the portal. Our results suggest that both Q[7] and iQ[7] could be promising candidates for excipients used in medicinal and pharmaceutical research fields.Graphical abstractQ[7] and iQ[7] could be promising candidates for excipients used in medicinal and pharmaceutical research fields.Graphical abstract for this article
       
  • Nanostructured pH-responsive biocompatible chitosan coated copper oxide
           nanoparticles: A polymeric smart intracellular delivery system for
           doxorubicin in breast cancer cells

    • Abstract: Publication date: Available online 25 April 2018Source: Arabian Journal of ChemistryAuthor(s): Nipun Babu Varukattu, Raju Vivek, Chandrababu Rejeeth, Ramar Thangam, Thondhi Ponraj, Alok Sharma, Soundarapandian Kannan In this study, we report a novel feasible single step reduction method for the active synthesis of biocompatible chitosan coated copper oxide nanoparticles (Cs-CuO NPs), for loading and delivery of doxorubicin (DOX) into breast cancer cells. The formulated nanoparticles (NPs) were characterized by size, shape and surface charge using various sophisticated instruments. Interestingly, these formulated particles showed profound drug loading activity and also showed its versatile nature of DOX release at different pH which makes them as ideal particles for breast cancer therapy. Intracellular uptake was evaluated through fluorescence microscopy studies with the help of coumarin. Morphological and apoptotic studies with the DOX-Cs-CuO NPs on MCF-7 cells showed its ability to induce apoptosis in breast cancer cells, which was clearly substantiated by ROS generation with the loss of mitochondrial membrane potential. Our results clearly showed the therapeutic nature of novel biocompatible Cs-CuO NPs in delivering DOX with a pH-dependent manner.
       
  • Low-loading of oxidized platinum nanoparticles into mesoporous titanium
           dioxide for effective and durable hydrogen evolution in acidic media

    • Abstract: Publication date: Available online 25 April 2018Source: Arabian Journal of ChemistryAuthor(s): Mabrook S. Amer, Mohamed A. Ghanem, Abdullah M. Al-Mayouf, Prabhakarn Arunachalam, Nezar H. Khdary Low-loading of oxidized platinum nanoparticles (0.1–0.5 wt%) was incorporated into mesoporous titanium dioxide support (Ptx/meso-TiO2) via evaporation self-assembly (ESA) approach followed by a two-step calcination processes. The physicochemical characterizations showed that the oxidized Ptx/meso-TiO2 catalysts exhibit high surface area around 200 m2/g and Pt nanoparticles having an average size of 3.0 nm are uniformly incorporated into the mesoporous TiO2 matrix with the existence of Pt(II) and Pt(IV) oxidation states. The Ptx/meso-TiO2 electrocatalysts showed an enhanced electrocatalytic activity with hydrogen evolution onset potential at −10 mV vs. RHE, Tafel slope of −110 mV/dec, small charge transfer resistance, and mass activity that reaches up to 25.7 A/mgPt at −300 mV vs. RHE. The hydrogen evolution mass activity of Ptx/meso-TiO2 electrocatalysts is significantly more efficient than the commercial Pt/C catalysts and Pt nanoparticles supported on nanostructured carbon substrates. Moreover, the Ptx/meso-TiO2 electrocatalysts exhibit excellent durability for a 24-hour electrolysis in acid solution with a further current activation during the prolonged electrolysis. The enhanced mass activity and durability are attributed to the substrate mesoporosity, uniform distribution and strong bonding between the oxidized Pt nanoparticles and the TiO2 substrate. These results demonstrate the promise of the mesoporous TiO2 substrate modified with low loading of platinum nanoparticles for energy conversion technologies.
       
  • Anchoring N-Halo (sodium dichloroisocyanurate) on the nano-Fe3O4 surface
           as “chlorine reservoir”: Antibacterial properties and wastewater
           treatment

    • Abstract: Publication date: Available online 25 April 2018Source: Arabian Journal of ChemistryAuthor(s): Ardeshir Khazaei, Negin Sarmasti, Jaber Yousefi Seyf, Zohreh Merati A novel retrievable bifunctional magnetic nano-structure (sodium dichloroisocyanurate immobilized on the Fe3O4@SiO2@Si(CH2)3Cl surface) was synthesized. Its antibacterial performance as water disinfectant successfully evaluated. The value of Minimum Bactericidal Concentration (625 ppm) and Minimum Inhibitory Concentration (314.5 ppm) show that magnetic nano-structure is a very effective antibacterial structure against the E. coli bacteria. In addition the viability of bacteria (%) was evaluated at different contact time against magnetic nano-structure. The disinfection procedure is very clean without any residual cyanuric acid in water. In other hand, oxidizing performance of nano-structure against the azo dye (acid red-18) was evaluated which attributed to the releasing HOCl in water. Kinetic of dye removal was measured at 0.01, 0.05, 0.1, and 0.5 g of nano-structure. Reducing pH and increasing temperature leads to increased Acid Red 18 degradation. Chemical oxygen demand (COD) measurement shows the effectiveness of nano-structure in acid red-18 degradation.The nano-structure turns to be magnetically retrievable, clean disinfectant, wastewater treatment agent, and its chlorine can be regenerated simply by exposure to household bleach such as Ca(OCl)2.
       
  • Integration of virtual screening and computational simulation identifies
           photodynamic therapeutics against human Protoporphyrinogen Oxidase IX
           (hPPO)

    • Abstract: Publication date: Available online 25 April 2018Source: Arabian Journal of ChemistryAuthor(s): Amir Zeb, Chanin Park, Minky Son, Ayoung Baek, Yeongrae Cho, Donghwan Kim, Shailima Rampogu, Gihwan Lee, Youn-Sig Kwak, Seok Ju Park, Keun Woo Lee Photodynamic therapy (PDT) is a rapidly evolving area of cancer management against solid tumors. PDT is either administrated by injecting photosensitizer (porphyrins) or by accumulation of intracellular protoporphyrin IX via the inhibition of human Protoporphyrinogen Oxidase IX (hPPO). In this study, novel inhibitors of hPPO have been investigated by integrating virtual screening, molecular docking, and molecular dynamics (MD) simulation. A ligand-based pharmacophore was generated from a training set of 22 inhibitors of hPPO. The selected pharmacophore had four chemical features including three hydrogen bond acceptors and one hydrophobic. The pharmacophore was characterized by highest correlation coefficient of 0.96, cost difference of 53.20, and lowest root mean square deviation of 0.73. The resultant pharmacophore was validated by Fischer’s Randomization and Test Set Validation methods. The validated pharmacophore was used as a 3D query to screen chemical databases including NCI, Asinex, Chembridge, and Maybridge. The screening of chemical databases and the subsequent application of Lipinski’s Rule of Five, and ADMET Assessment Test, retrieved 1176 drug-like compounds. The drug-like compounds were subjected to molecular docking studies in the active site of hPPO to eliminate false positive hits and to elucidate their true binding orientation. Top three candidate molecules with high docking scores and hydrogen bond interactions with catalytic active residues were selected as best candidate inhibitors against hPPO. The binding stability of selected candidate inhibitors was evaluated by MD simulation. The MD simulation of hits portrayed strong hydrogen bonds and key hydrophobic interactions with catalytic active residues of hPPO including R59, R97, G159, G332 and flavin moiety of FAD (coenzyme of hPPO). Our study predicts three hit compounds against hPPO, which could possibly accumulate high concentration of protoporphyrinogen-IX, and thereby acting as an intracellular photosensitizer against tumor cells through photodynamic therapy.
       
  • Unveiling interactions between DNA and cytotoxic
           2-arylpiperidinyl-1,4-naphthoquinone derivatives: A combined
           electrochemical and computational study

    • Abstract: Publication date: Available online 25 April 2018Source: Arabian Journal of ChemistryAuthor(s): Christian Espinosa-Bustos, Camila Canales, Galo Ramírez, Pablo Jaque, Cristian O. Salas Three 2-arylpiperidinyl-1,4-naphthoquinone derivatives were synthesized and evaluated in vitro to determine their cytotoxicity on cancer and normal cell lines. In order to establish their possible action mechanism, the electrochemical behaviour of these quinones was examined using cyclic voltammetry (CV) as technique by using a three-electrode setup: a glassy carbon, Ag/AgCl (in 3 M KCl), and platinum wire as working, reference, and counter electrodes, respectively. Kinetic studies were done to determine the control of the reduction reaction and the number of transferred electrons in the process. Furthermore, the addition of dsDNA to the quinone solutions allowed for the observation of an interaction between each quinone and dsDNA as the current-peaks became lower in presence of dsDNA. Otherwise, motivated to support the aforementioned results, electronic structure calculations at the TPSS-D3/6-31+G(d,p) level of theory were carried out in order to find the most favourable noncovalently bonded complexes between quinones and DNA. Noncovalent complexes formed between DNA and 2-arylpiperidinyl-1,4-naphthoquinones and stabilized by π-stacking interactions along with the well-known hydrogen-bonded complexes were found, with the former being more stable than the latter. These results suggest that the intercalation of these quinone derivatives in DNA is the most likely action mechanism.
       
  • Impact of annealing on the structural and optical properties of ZnO
           nanoparticles and tracing the formation of clusters via DFT calculation

    • Abstract: Publication date: Available online 22 April 2018Source: Arabian Journal of ChemistryAuthor(s): Rezq Naji Aljawfi, Mohammad Jane Alam, F. Rahman, Shabbir Ahmad, Aga Shahee, Shalendra Kumar In this report, nanoparticles (NPs) of zinc oxide (ZnO) were synthesized through auto-combustion route and annealed in air at different temperatures: 200, 400, 600 and 800 °C. The single phase nature has been confirmed via X-ray diffraction (XRD) and selected area electron diffraction (SAED) analysis. The average of crystallite sizes increased progressively as the thermal annealing increase and ranging between 13.8 and 39.7 nm. Raman spectra resembled to that of hexagonal ZnO wurtzite structure, the narrowing in E2H (438 cm−1) Raman phonon mode in sequence with further annealing indicates improvement in the crystallinity and reduction in the local atomic defects of oxygen vacancy (Vo2+). The defects create energy deep bands within the band gap region and diminish the UV emission efficiency that has been assessed through photoluminescence (PL) spectroscopic. The donor band of oxygen vacancy (Vo2+) was ∼1 eV above valence band (VB), whereas the acceptor band of zinc vacancy (VZn2−) was at ∼0.85 eV above the VB. The ZnO NPs that was annealed at lowest temperature of 200 °C exhibited different behavior trend in which the UV-PL band was diminished clearly, blue shifted to lower wave length and appeared as small plateau at the range of 380–270 nm corresponding to high band gap energy (3.8–4.6 eV), which is indicative to low crystal quality and presence of clusters. We used density function theory (DFT) calculation for computing the HOMO-LUMO band gap of supposed clusters ZnnOn (n = 2, 3, 5, 10). The high band gap energy of the simulated clusters was agreed with that of ZnO NPs annealed at 200 °C that gives indirect evidence on the formation of clusters.
       
  • Acetocatechol functionalized viologen as polyfunctional material that
           responds to anion, cation and reductant in aqueous and organic solvents

    • Abstract: Publication date: Available online 17 April 2018Source: Arabian Journal of ChemistryAuthor(s): Huanhuan Qiao, Yue-Ling Bai, Yongmei Zhao, Feifei Xing, Ming-Xing Li, Shourong Zhu Both viologen and catechol have been studied extensively. However, the stability of catechol-Fe(III) without additional oxidant is still not well understood. In this paper, we introduced acetocatechol into viologen to investigate its interactions with anion, cation, and reductant, as well as the stability of its Fe(III) complexes. This acetocatechol functionalized viologen, 1,1'-bis(2-(3,4-dihydroxyphenyl)-2-oxoethyl)- [4,4'-bipyridine]-1,1'-diium chloride (H6V·Cl2) exists in central symmetric ketone cation form in solid state. Viologen cation increased the acidity of the aceto group and deprotonated the enolic proton to form monodeprotonated enolic H5V+ in the presence of anion/base, which had the deepest color in organic solvents. The absorbance maximum of H5V+ increased with the decrease of solvent polarity. It also interacted with B4O72- and MoO42- by forming catechol ester in DMSO solution. The catechol moiety can coordinate to metal ion, especially Fe(III), in both aqueous and DMSO solution. In particular, it coordinated to Fe(III) much more readily in aqueous solution than in DMSO. Green monocatecholato Fe(III) and red-brown bis-catecholato Fe(III) complex also formed in aqueous solution. The monocatecholato Fe(III) complex first-order dimerized in aqueous solution at room temperature but underwent second-order decomposition to Fe(II) complex at 60°C. The biscatecholato Fe(III) complex also transferred to other Fe(III) complexes at first- and second-order at room-temperature and 60 °C respectively. The t1/2 varied from several hours at room-temperature and several minutes at 60 °C at 10-4 M concentration. The interactions of Fe(III) in DMSO is much more complex than that of acetocatecholate without viologen. Fe(III) can also be reduced to free viologen radicals in the presence of sodium Na2S2O4, but not N2H4. In conclusion, this polyfunctional compound responds to anion via aceto and catechol, metal ion via catechol hydroxyl, while reductant via viologen.Graphical abstractAcetocatechol viologen can response to anion via aceto, metal ion via catechol hydroxyl and reductant via viologen. Its Fe(III) complex decay first- and second-order at RT and 60°C respectively.Graphical abstract for this article
       
  • Microparticles based on carboxymethyl starch/chitosan polyelectrolyte
           complex as vehicles for drug delivery systems

    • Abstract: Publication date: Available online 16 April 2018Source: Arabian Journal of ChemistryAuthor(s): Rafael F.N. Quadrado, André R. Fajardo Microparticles with oval-shape morphology and rough and porous surfaces were prepared by polyelectrolyte complexation of carboxymethyl starch (CMS) and chitosan (Cs). CMS with DS of 0.5, the polyanionic moiety, was synthesized from rice starch with low content of amylose (6%). A preliminary investigation revealed that this kind of starch is more susceptive to esterification than rice starches with higher contents of amylose. The CMS/Cs microparticles showed higher chemical and thermal stability than microparticles prepared by conventional ionotropic crosslinking of Cs with TPP ions. The carboxymethyl groups of CMS are more efficient to neutralize the positive groups of Cs and, also, enhance the entrapment of bovine serum albumin (BSA) in the CMS/Cs matrix as compared to Cs/TPP. In vitro experiments conducted in simulated gastric fluid (pH 1.2) and simulated intestinal fluid (pH 6.8) with the testing microparticles revealed that the CMS/Cs-BSA microparticles exhibit a highlighted pH-dependent release profile. This desirable property allows controlling the release of BSA more efficiently, which minimizes undesirable issues (e.g. burst effect and non-sustained release). Furthermore, the BSA release from CMS/Cs-BSA microparticles in SIF follows an ideal Zero-order kinetics, which is very attractive for a drug delivery system. Therefore, microparticles based on CMS/Cs polyelectrolyte complex may be promising to control the drug release in specific regions of the gastrointestinal tract.Graphical abstractGraphical abstract for this article
       
  • Porous multifunctional fluoropolymer composite foams prepared via humic
           acid modified Fe3O4 Nanoparticles stabilized Pickering high internal phase
           emulsion using cationic fluorosurfactant as co-stabilizer

    • Abstract: Publication date: Available online 14 April 2018Source: Arabian Journal of ChemistryAuthor(s): Umair Azhar, Chenxi Huyan, Xiaozheng Wan, Chuanyong Zong, Anhou Xu, Jitao Liu, Jiachen Ma, Shuxiang Zhang, Bing Geng Fluoropolymers are very important owing to their excellent application performances, especially in extreme conditions. On the other hand, the preparation of porous fluoropolymers is a difficult task due to unavailability of suitable surfactants as well as tedious synthesis steps. Here we prepared multifunctional porous fluoropolymer composite foams with a simple process of “high internal phase emulsion (HIPE)” by using humic acid modified iron oxide nanoparticles (HA-Fe3O4 NPs) and cationic fluorosurfactant (CFS) (PDMAEMA-b-PHFBA) as co-stabilizer. The inclusion of HA-Fe3O4 NPs in the system made fluoro-HIPE more stable than the emulsion prepared using only CFS or other conventional stabilizers. Morphology of the prepared polyHIPE was easily controlled by altering the concentration of HA-Fe3O4 and/or CFS in the original formulation. Adjustment of the porous structure with open/close cells was performed and the average diameter of the pores tuned between 4.9-23 μm. With the increase in specific surface area by using nanoparticles (NPs) and CFS as co-surfactants, Pickering HIPE monoliths adsorbed double amount of oil compared to foams based solely on HIPE template. Multiple functional groups were bound onto Fe3O4 NPs through HA modification that made the fluoro-monolith capable of adsorbing dye, i.e. methylene blue, from water. A simple centrifugation enabled regeneration of the oil soaked foams and adsorption capacity was not decreased after 10 adsorption/regeneration cycles.
       
  • Hierarchical nanocrystalline NiO with coral-like structure derived from
           nickel galactarate dihydrate: An active mesoporous catalyst for methyl
           ethyl ketone production

    • Abstract: Publication date: Available online 14 April 2018Source: Arabian Journal of ChemistryAuthor(s): Samih A. Halawy, Mohamed A. Mohamed, Adel Abdelkader Nanocrystalline NiO with a coral-like structure (38 nm) has been prepared via thermal decomposition of a new precursor, nickel galactarate (NiC6H8O8·2H2O), at 500 °C for 3 h in air. Thermal decomposition of that precursor was studied by TG and DSC techniques. The resultant NiO was physicochemically characterized by XRD, FTIR, SEM, surface area, porosity and CO2-TPD. NiO was found to exhibit a remarkable activity towards the synthesis of MEK from 2-butanol between 200 and 325 °C. In addition, it has shown a great tendency to ease regeneration of the used catalyst after 192 h in stream by simple refreshing method.
       
  • Analysis of amphetaminic drug compounds in urine by headspace-dielectric
           barrier discharge ionization-mass spectrometry

    • Abstract: Publication date: Available online 11 April 2018Source: Arabian Journal of ChemistryAuthor(s): Ahsan Habib, Aklima Nargis, Lei Bi, Peng Zhao, Wen Luhong Rapid detection of trace level amphetaminic drug compounds in urine is essential to monitor consumption of these abuse drugs by athletes. In this work, the amphetaminic drug compounds were spiked in human urine and analyzed using headspace - dielectric barrier discharge (DBD) ionization-mass spectrometry method. In the headspace method, the urine spiked drug compound was treated with alkali solution, thus the free base amphetaminic molecules were released into the gas phase. The gaseous molecules were then ionized by the DBD ion source placed in front of the mass spectrometer inlet under ambient condition. This method provided comparable sensitivity with the solid-phase microextraction (SPME) in analysis of the amphetaminic compounds where no derivatization or adduct formation was required. The present method also facilitated the sensitivity enhancement with about one order of magnitude in urine compared to standard solution. Carbonate alkali solution showed the highest sensitivity for detection of the drug compounds in urine and the sensitivity was enhanced by using NH3. The limits of detection (LODs) of the various amphetaminic molecules were found to be in the range of 0.10-0.80 ng/mL for standard solutions while those for urine were in the range of 0.04-0.40 ng/mL. The analytical figures of merit of this method were evaluated under ambient condition using suitable internal standard. Results suggested the suitability of this method for analytical routine work in detection of amine-based drugs in doping test and/or in forensic laboratories. A mechanism of enhanced sensitivity by the ammoniated carbonate alkali solution in urine is also discussed.
       
  • Aloe-vera flower shaped rutile TiO2 for selective hydrogenation of
           nitroaromatics under direct sunlight irradiation

    • Abstract: Publication date: Available online 10 April 2018Source: Arabian Journal of ChemistryAuthor(s): Satnam Singh, Roopchand Prajapat, Rayees Ahmad Rather, Bonamali Pal This study reveals the fabrication of a sunlight receptive flower shaped rutile TiO2 microstructure (F-TiO2) for the selective photoreduction of nitroaromatics. The crystalline F-TiO2 possesses small band gap (∼2.8 eV) and large specific surface area (193 m2g−1). Moreover, the F-TiO2 exhibited higher relaxation time (120 µs) for the electron-hole pairs due to its brilliant multi dimensional morphology that enables shorter diffusion path and multiple scattering of active sites. The experimental results revealed the superior photocatalytic activity of the F-TiO2 microstructure in contrast to active P25 and rutile TiO2 (obtained from thermally treated P25 at 800 °C for 4 h) for the reduction of nitrobenzene, m-dinitrobenzene and 2,2-dinitrobiphenyl in 50% aqueous isopropanol (hole scavenger) to aniline (42–72%), m-nitroaniline (37–42%), m-phenylenediamine (88–100%) and benzo[c]cinnoline (80–94%) respectively under UV and direct sunlight irradiation. The quantitative estimation of byproducts like acetone and hydrogen (H2) produced from iso-propanol oxidation and water splitting during instant reduction of nitroaromatics to aromatic amines is well correlated and explained on the basis of its beneficial surface structural and electronic properties.Graphical abstractSunlight active Aloe-vera flower shaped crystalline rutile TiO2 microstructures displayed good photocatalytic reduction ability for various nitro aromatics to their respective aromatic amines. Despite having rutile lattice structure this photocatalyst showed dominance of (1 1 0) and (1 0 1) facets as exposed reduction sites. Moreover, narrow band gap, higher specific surface area and lower rate of recombination for photogenerated charge carriers are responsible for better selectivity and higher yield in nitro aromatic reduction.Graphical abstract for this article
       
  • A novel and convenient oxidation-controlled procedure for the synthesis of
           oxazolines from TosMIC and aldehydes in water – Anti biofilm activity

    • Abstract: Publication date: Available online 5 April 2018Source: Arabian Journal of ChemistryAuthor(s): Rajan Abraham, Periakaruppan Prakash, Karthikeyan Mahendran, Murugappan Ramanathan A new convenient procedure for the synthesis of oxazolines from tosylmethyl isocyanide (TosMIC) and aldehydes using imidazole as an efficient catalyst has been reported. The synthesized oxazolines were able to be protected from the oxidation by using just water both as a good solvent and anti oxidant. All the synthesized compounds show good anti biofilm activity against Staphylococcus epidermidis.Graphical abstractGraphical abstract for this article
       
 
 
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