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  Subjects -> CHEMISTRY (Total: 809 journals)
    - ANALYTICAL CHEMISTRY (48 journals)
    - CHEMISTRY (563 journals)
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    - ELECTROCHEMISTRY (25 journals)
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CHEMISTRY (563 journals)                  1 2 3 4 5 6 | Last

2D Materials     Hybrid Journal   (Followers: 4)
Accreditation and Quality Assurance: Journal for Quality, Comparability and Reliability in Chemical Measurement     Hybrid Journal   (Followers: 31)
ACS Catalysis     Full-text available via subscription   (Followers: 25)
ACS Chemical Neuroscience     Full-text available via subscription   (Followers: 13)
ACS Combinatorial Science     Full-text available via subscription   (Followers: 8)
ACS Macro Letters     Full-text available via subscription   (Followers: 19)
ACS Medicinal Chemistry Letters     Full-text available via subscription   (Followers: 25)
ACS Nano     Full-text available via subscription   (Followers: 334)
ACS Photonics     Full-text available via subscription   (Followers: 6)
ACS Synthetic Biology     Full-text available via subscription   (Followers: 9)
Acta Chemica Iasi     Open Access  
Acta Chimica Sinica     Full-text available via subscription  
Acta Chimica Slovaca     Open Access   (Followers: 6)
Acta Chromatographica     Full-text available via subscription   (Followers: 10)
Acta Facultatis Medicae Naissensis     Open Access   (Followers: 1)
Acta Metallurgica Sinica (English Letters)     Hybrid Journal   (Followers: 5)
adhäsion KLEBEN & DICHTEN     Hybrid Journal   (Followers: 4)
Adhesion Adhesives & Sealants     Hybrid Journal   (Followers: 5)
Adsorption Science & Technology     Full-text available via subscription   (Followers: 8)
Advanced Functional Materials     Hybrid Journal   (Followers: 38)
Advances in Chemical Engineering and Science     Open Access   (Followers: 22)
Advances in Chemical Science     Open Access   (Followers: 9)
Advances in Colloid and Interface Science     Full-text available via subscription   (Followers: 15)
Advances in Drug Research     Full-text available via subscription   (Followers: 16)
Advances in Fluorine Science     Full-text available via subscription   (Followers: 7)
Advances in Fuel Cells     Full-text available via subscription   (Followers: 12)
Advances in Heterocyclic Chemistry     Full-text available via subscription   (Followers: 8)
Advances in Materials Physics and Chemistry     Open Access   (Followers: 16)
Advances in Nanoparticles     Open Access   (Followers: 12)
Advances in Organometallic Chemistry     Full-text available via subscription   (Followers: 9)
Advances in Polymer Science     Hybrid Journal   (Followers: 39)
Advances in Protein Chemistry     Full-text available via subscription   (Followers: 6)
Advances in Protein Chemistry and Structural Biology     Full-text available via subscription   (Followers: 10)
Advances in Quantum Chemistry     Full-text available via subscription   (Followers: 4)
African Journal of Chemical Education     Open Access   (Followers: 1)
African Journal of Pure and Applied Chemistry     Open Access   (Followers: 4)
Afrique Science : Revue Internationale des Sciences et Technologie     Open Access   (Followers: 1)
Agrokémia és Talajtan     Full-text available via subscription   (Followers: 1)
Alchemy     Open Access   (Followers: 3)
Alkaloids: Chemical and Biological Perspectives     Full-text available via subscription   (Followers: 4)
AMB Express     Open Access  
American Journal of Applied Sciences     Open Access   (Followers: 30)
American Journal of Biochemistry and Biotechnology     Open Access   (Followers: 201)
American Journal of Biochemistry and Molecular Biology     Open Access   (Followers: 11)
American Journal of Chemistry     Open Access   (Followers: 18)
American Journal of Plant Physiology     Open Access   (Followers: 10)
American Mineralogist     Full-text available via subscription   (Followers: 4)
Analyst     Full-text available via subscription   (Followers: 35)
Angewandte Chemie     Hybrid Journal   (Followers: 18)
Angewandte Chemie International Edition     Hybrid Journal   (Followers: 262)
Annales UMCS, Chemia     Open Access   (Followers: 2)
Annual Reports in Computational Chemistry     Full-text available via subscription   (Followers: 1)
Annual Reports Section A (Inorganic Chemistry)     Full-text available via subscription   (Followers: 2)
Annual Reports Section B (Organic Chemistry)     Full-text available via subscription   (Followers: 4)
Annual Review of Chemical and Biomolecular Engineering     Full-text available via subscription   (Followers: 10)
Annual Review of Food Science and Technology     Full-text available via subscription   (Followers: 11)
Anti-Infective Agents     Hybrid Journal   (Followers: 1)
Applied Organometallic Chemistry     Hybrid Journal   (Followers: 4)
Applied Spectroscopy     Full-text available via subscription   (Followers: 12)
Applied Surface Science     Hybrid Journal   (Followers: 19)
Arabian Journal of Chemistry     Full-text available via subscription   (Followers: 6)
ARKIVOC     Open Access   (Followers: 1)
Asian Journal of Biochemistry     Open Access   (Followers: 1)
Australian Journal of Chemistry     Hybrid Journal   (Followers: 4)
Autophagy     Full-text available via subscription   (Followers: 1)
Avances en Quimica     Open Access   (Followers: 1)
Biochemical Pharmacology     Hybrid Journal   (Followers: 6)
Biochemistry     Full-text available via subscription   (Followers: 253)
Biochemistry Insights     Open Access   (Followers: 4)
Biochemistry Research International     Open Access   (Followers: 4)
BioChip Journal     Hybrid Journal   (Followers: 1)
Bioinorganic Chemistry and Applications     Open Access   (Followers: 4)
Bioinspired Materials     Open Access  
Biointerface Research in Applied Chemistry     Open Access   (Followers: 1)
Biointerphases     Open Access  
Biomacromolecules     Full-text available via subscription   (Followers: 17)
Biomass Conversion and Biorefinery     Partially Free   (Followers: 5)
Biomedical Chromatography     Hybrid Journal   (Followers: 7)
Biomolecular NMR Assignments     Hybrid Journal   (Followers: 2)
BioNanoScience     Partially Free   (Followers: 4)
Bioorganic & Medicinal Chemistry     Hybrid Journal   (Followers: 30)
Bioorganic & Medicinal Chemistry Letters     Hybrid Journal   (Followers: 24)
Bioorganic Chemistry     Hybrid Journal   (Followers: 5)
Biopolymers     Hybrid Journal   (Followers: 14)
Biosensors     Open Access   (Followers: 3)
Biotechnic and Histochemistry     Hybrid Journal   (Followers: 1)
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: 13)
Canadian Association of Radiologists Journal     Full-text available via subscription   (Followers: 3)
Canadian Journal of Chemistry     Full-text available via subscription   (Followers: 6)
Canadian Mineralogist     Full-text available via subscription   (Followers: 1)
Carbohydrate Research     Hybrid Journal   (Followers: 11)
Carbon     Hybrid Journal   (Followers: 54)
Catalysis for Sustainable Energy     Open Access   (Followers: 2)
Catalysis Reviews: Science and Engineering     Hybrid Journal   (Followers: 5)
Catalysis Science and Technology     Free   (Followers: 4)
Catalysis Surveys from Asia     Hybrid Journal   (Followers: 4)
Catalysts     Open Access   (Followers: 7)
Cellulose     Hybrid Journal   (Followers: 5)

        1 2 3 4 5 6 | Last

Journal Cover Chemistry and Materials Research  
   [12 followers]  Follow    
  This is an Open Access Journal Open Access journal
   ISSN (Print) 2224-3224 - ISSN (Online) 2225-0956
   Published by International Institute for Science, Technology and Education (IISTE) Homepage  [30 journals]
  • Spray Freeze Drying as a Smart Method in Preparation of Ultra-Fine
           CeO2-MOX Materials

    • Authors: Dalia R. Abd El-Hafiz, Mohamed A. Ebiad, Lamia. S. Mohamed
      Abstract: Cerium-oxide based nano-materials attract increasing interest for their use in multiple applications. In particular, the substitution of Ce atoms by other elements with lower or higher oxidation state is used to control oxygen vacancies within the oxide structures, which can greatly enhance the material properties for catalysis applications. Among the synthesis approaches, spray freeze drying method has been proved to be an extremely efficient method for the preparation of uniform nano-partical for different application. In this method, the pure solution or mixed solutions were directly sprayed into liquid nitrogen and immediately frozen to form a suspension, then, the iced droplets were dried in the freeze-dryer to reach the final product. However, in this work we deal with, the preparation of ultra-fine materials based on CeO2 fluorite structures and the substitution in its lattice with La and/or Co metal. The effect of Ce/La ratio on the properties of the final product was also investigated. During the experiment, the advantage of spray-freeze-drying process was successfully achieved. The characterization of the powder product was analyzed by means of EDX, TGA, XRD, DLS, and TEM which confirm the formation of nano-particles in the fluorite structure. For Ce:Co and when the Ce: La ratio is 0.2, 0.5, only cubic phase of CeO2-MO2 solid solution with ?uorite structure is observed with hig oxygen storage capacity, while Ce-La1 show the hcp structure of lanthanum. Keywords: nano-materials, Ceria, Lanthanium, metal loading spray freeze drying
      Issue No: Vol. 6
       
  • Application of Cleaner Production in Palm Oil Mill: A Case Study at PT
           Perkebunan Nusantara IV Adolina Business Unit Perbaungan North Sumatera
           Indonesia

    • Authors: Tajuddin Bantacut, Suprihatin ., Panji Maulana
      Abstract: Palm oil mill (POM) produces CPO (Crude Palm Oil), PKO (Palm Kernel Oil) and wastes (solid, liquid and gas). Environmental pollution has existed together with palm oil processing. Being reactive approach, wastes treatment and disposal conducted by palm oil mill still creates some environmental problems. Cleaner production is a proactive approach concentrates on minimizing wastes through improving effectiveness and efficiency of the process. This research identified and analyzed the alternatives of cleaner production application in palm oil mill with special reference to PT Perkebunan Nusantara IV Adolina in North Sumatera, Indonesia. The analysis focused on technical, financial and environmental aspects of each possible alternative. AHP (Analytical Hierarchy Process) was used to rank alternatives by experts judgment. The results arranged the priority of alternatives: optimization of Standard Operational Procedure application, improvement of efficiency of water use, good operating procedures, utilization of palm oil mill effluent as biogas, optimizing the utilization of empty fruit bunches, free fatty acid control, collection of split oil by making condensate pond, and preventing contamination of fresh fruit bunches. The application of good house-keeping provides financial gain of 1.89 billion rupiah/year, process modification 0.28 billion rupiah/year, and on-site reuse of wastes 1.69 billion rupiah/year (exchange rate was Rp. 10,000/US$). An advance research is needed to make detail quantification and integration of all related benefits both economic and environmental aspects. Keywords: palm oil industry, cleaner production, analytical hierarchy process, case study, Indonesia
      Issue No: Vol. 6
       
  • Simultaneous Quantification of Lamivudine, Zidovudine and Related
           Impurities in Fixed Oral Dosage Combination Using RP-HPLC with DAD
           detection

    • Authors: Gordon A., Gati L, Akanji O, Asante SB, Osei-Adjei G, Tuani YT, Hackman HK
      Abstract: A simple and fast isocratic Reverse Phase High Performance Liquid Chromatography (RP-HPLC) method has been developed and validated for the simultaneous determination of Lamivudine, zidovudine and their related impurities in tablets. The method consists of a mobile phase combination of Acetonitrile (HPLC grade) and Buffer (0.0680 g of Potassium Dihydrogen Orthophosphate, 0.3 ml of Triethylamine, pH adjusted to 8.0 with Orthophosphoric acid to a final volume preparation of 100 ml) in the ratio 10:90. Phenomenex Luna 5-µm C18 (2)-250 x 4.6-mm, 5-µm) was used as the stationary phase. The column oven was set to a temperature of 30±1oC. Quantification was achieved with a DAD detector set at 270 nm. Resolution was achieved at a short run time of 25 minutes. Zidovudine related impurity C, Lamivudine, salicylic acid, Zidovudine and Zidovudine related impurity B eluted at 3.749±0.004, 4.862±0.013, 15.332±0.064, 21.201±0.076 and 23.682±0.117 respectively. Relative retention times (RRT) for lamivudine unknown related impurities with respect to Zidovudine were 0.15, 0.17, 0.30 and 0.59. RRT for Zidovudine unknown related impurities with respect to Zidovudine were 0.39 and 0.63.  The method was found to be specific, robust, accurate and precise for the estimation of Zidovudine related impurity C, Lamivudine, salicylic acid, Zidovudine and Zidovudine related impurity B in fixed oral dosage tablets over the concentration ranges of 0.0204 mg/mL-0.0088 mg/mL, 0.0962 mg/mL-0.7699 mg/mL, 0.1929 mg/mL-1.5410 mg/mL and 0.0088 mg/mL-0.024 mg/mL respectively. The Correlation Coefficient (r2) for Zidovudine related impurity C, Lamivudine, salicylic acid, Zidovudine and Zidovudine related impurity B were greater than 0.998. The LOD were found to be between 1.9x10-4 mg/mL to 2.69 x10-4 mg/mL.  The proposed method is precise, specific, accurate and robust for the simultaneous estimation of Zidovudine related impurity C, Lamivudine, salicylic acid, Zidovudine, Zidovudine related impurity B and other related impurities in dosage forms. Keywords: Zidovudine related impurity C, Lamivudine, salicylic acid, Zidovudine, Zidovudine related impurity B, Lamivudine related impurities, Zidovudine related impurities RP-HPLC, Validation.  
      Issue No: Vol. 6
       
  • Relative Response Factor for Lamivudine and Zidovudine Related substances
           by RP-HPLC with DAD detection

    • Authors: Gordon A., Gati L., Asante SB, Fosu SA, Hackman HK, Osei-Adjei G, Tuani YT
      Abstract: A study was conducted to establish the Relative Response Factors for Zidovudine related impurity C, Lamivudine salicylic acid and Zidovudine related impurity B.  A simple and fast isocratic Reverse Phase High Performance Liquid Chromatography (RP-HPLC) method was used for the simultaneous determination of the related impurities. The method consists of a mobile phase combination of Acetonitrile (HPLC grade) and Buffer (0.0680 g of Potassium Dihydrogen Orthophosphate, 0.3 ml of Triethylamine, pH adjusted to 8.0 with Orthophosphoric acid to a final volume preparation of 100 ml) in the ratio 10:90 using Phenomenex Luna 5-µm C18 (2)-250 x 4.6-mm, 5-µm) as a stationary phase, flow rate of 1.0 mL/min with detection at 270 nm. The RRF for Zidovudine related impurity C, Lamivudine salicylic acid and Zidovudine related impurity B were 2.07, 0.13 and 1.28 respectively.   Results obtained for quantification of the related substance in lamivudine and zidovudine single dose oral solid dosage form using the RRF and know standards shows no significant difference at 95 % confidence interval. The RRF can therefore be used for the quantification of know related impurities in lamivudine zidovudine oral dosage form using the stated chromatographic conditions.
      Issue No: Vol. 6
       
  • The Substitutional Effects on the Carbonyl and Metal -Oxygen Stretching
           Frequencies of Some 4-Acyl Functional Derivatives of 1-Phenyl-3-Methyl -4-
           Acyl Pyrazol -5- ones and Thier Divalent Metal Chelates

    • Authors: Obinna Okpareke, Emmanuel Okafor, Pius Ukoha, Solomon Okereke
      Abstract: The divalent  metal complexes of Mg (II), Co (II), Cu (II) and Zn (II) ions with some 1-phenyl-3-methyl-4-acyl pyrazolone-5 have been synthesized and characterized by physical methods such as elemental analysis , U.V, and I.R spectral analyses. The corroborative evidences from elemental analysis and spectral data show that complexes are neutral dihydrated  bischelates  conforming to the general formula ML2.2 H2O , where  M= Mg2+,Co2+,Cu2+ and Zn2+ ions and L= anions of  the 4-acyl pyrazolone ligand. Infrared spectral assignments(4000 -  400cm?1) were made and interpretation  of the spectral data revealed that the stability of C=O bond increased while that of the M=O bond decreased with increase in the number of carbon atoms of the 4-acyl substituent. Keywords:  Stretching frequencies, 4 – acylpyrazolon-5 ,divalent metal chelates.
      Issue No: Vol. 6
       
  • Production of 75pb-15sb-10sn/ 10%V/V Sio2 Particulate Composite and Ageing
           Characteristics

    • Authors: Ihom; A.P., Anbua, E.E., Nyior, G.B., Nor Iv, J.
      Abstract: The research titled `production of 75Pb-15Sb-10Sn/10%v/v SiO2 Particulate composite and ageing characteristics’ has been carried out. The composite was produced using 75Pb-15Sb-10Sn alloy matrix and silica particles as reinforcing agent. The composite was produced using the stir-cast method. The reinforcing agent was produced from quartz which was ground to 63 microns passing using a laboratory ball mill. 10%v/v of the silica was added to the molten alloy during the production process. The produced composite was prepared into specimens, some of which were solution treated at 300oC and then aged hardened at various ageing times and a constant temperature of 100OC. The test specimens were then subjected to hardness test, and microstructural examination. The result of the hardness test showed that the composite in the as cast form had a hardness value of 32.5HRB which is higher than that of the ordinary alloy which is 27.7HRB. The result of the ageing characteristics showed that the best ageing time for the developed composite is 3 hours, the highest hardness value of 36HRB occurred after 3 hours of ageing. The microstructure of the composite revealed the constituent phases and gave more insight as to the hardness variation on ageing. Keywords: Ageing, Composite, Production, Particulate, Characteristics  
      Issue No: Vol. 6
       
  • Preparation ,Characterization and Thermal Properties of New Aromatic
           Polyester Based on Di ,Tri and Tetra Hydroxyl Monomers with 4,4Azo Di
           Benzoic Acid and Adipic Acid

    • Authors: Mohammed A. Mutar, Khitam Abdul Alameer
      Abstract: A series of new aromatic Polyesters were  synthesized by  polycondensation of various aromatic monomers  di ,tri and tetra diols (BCAHPMNM , BHPMB, BHPPB , BPBHP) with Acids(4,4Azo Di benzoic acid  and Adipic acid) using  dibutyltine dilaurate as Catalyst .all polyesters(P.E1-P.E4)containing pyridine heterocyclic group, aliphatic methylene linkage, and Azo group. The yield of Polyesters varies from 60-85%. All of  these  new  aromatic polyester  show very good  solubility in common organic  solvents , such as (pyridine , CHCl3 ,  CH2Cl2 , NaOH , H2SO4 , HNO3 , Acetone , Benzene ,  DMF , DMSO , THF) without need for heating. Thermal analysis of polyesters by thermo gravimetric analysis (TGA) reveals that these Aromatic polyesters possess thermal stability. Monomers and polyesters characterized by FT-IRand1HNMRspectrosticcopy. Keywords: Aromatic polyester , 4,4Azo Di benzoic acid  , Adipic acid,  dibutyltine dilaurate.
      Issue No: Vol. 6
       
  • Novel Polyesteramide Resin from Rubber Seed Oil for Surface Coating
           Application

    • Authors: E.O. Obazee, F.E. Okieimen
      Abstract: This paper reports the synthesis of rubber seed oil-based polyesteramide via maleinised rubber seed oil intermediate. Rubber seed oil was modified by treatment with maleic anhydride and subsequently reacted with diethanolamine. The synthesized intermediate and the resin were characterized by measurement of physico-chemical properties (acid value, iodine value, and saponification value), resistance to chemicals (water, dilute alkali, dilute acid, and brine) and drying time in comparison with medium oil-modified alkyd resin. The values of the measurement parameter suggest a potential for the application of polyesteramide resin in surface coating applications. Keywords: Rubber seed oil, maleinization, polyesteramide resin, low V.O.C., surface coating
      Issue No: Vol. 6
       
  • Assessment the Effects of Alpha Particles on Women's Urine using
           CR-39 NTDs

    • Authors: Najeba F. Salih; , Mohamad S. Jaafar, Ammar A. Battawy
      Abstract: This research describes the results that have been obtained from the alpha particles after carrying out the present study. The study was conducted on 60 urine samples taken from women, who were either infertile, had weak fertility with 30 urine samples of normal women. The age of those women ranged between (18-47) years. They further belonged to different locations in Iraqi Kurdistan region. values calculated in 20 ml of female urine samples was noted that the average values of concentrations of alpha emitters in 20 ml of urine of women's problem with fertility were 0.371 ppm in Erbil,  0.330 ppm in Sulaymania, and 0.199 for normal women, respectively, The results showed that the concentration of alpha emitters in Erbil > Sulaymania> normal, the number of areas do represent a source of danger to human life. This denotes that there is evidence of health problems. Significant difference found in participants’ laboratory outcomes between Erbil, Sulaymania and normal. Significant correlations (p < 0.001) found between participants’ demographic data and their laboratory outcomes. Also the range of alpha particles in the surface of urine samples and CR-39NTDs was calculated using SRIM program Keywords: infertility in women, Urine, Iraqi Kurdistan region, CR- 39NTDs, Alpha particles
      Issue No: Vol. 6
       
  • Removal of Zinc from Aqueous Solution by Adsorption using Coir Dust
           (Residue and Extract)

    • Authors: Aniekemeabasi Ubon Israel, Okon Okon
      Abstract: The adsorption behaviour of Zn (II) ions onto unmodified coconut coir dust residue and NaCl treated coconut coir dust extract (UCCR, UCCE, NaCCE and NaCCR) was investigated at 30oC and pH of 7.0. The trend in the percentage adsorption of the adsorbate on the adsorbents decreased in the following descending: UCCR NaCCE>NaCCR> UCCE. There was justification in modifying the coir dust extract since this enhanced its adsorptive capacity. However, modification of the coir residue decreased its adsorptive capacity and not justifiable. The sorption data were also subjected to Langmuir, Freundlich and Flory-Huggins adsorption isotherm models. The adsorption of Zn(II) ions on NaCl treated coir residue (NaCCR) conform to the Langmuir isotherm model with high correlation value R2 > 0.90. This indicated monolayer surface coverage of the Zn(II) ions on these adsorbents. The data for the adsorption on NaCl treated coir residue (NaCCR) and NaCl treated coir residue (NaCCR) at 50oC fitted well to the Freundlich isotherm model implying a heterogeneous surface coverage of the adsorbents. All the adsorptions of Zn(II) ions on these adsorption did not fit the Flory-Huggins model. The adsorption increased with increase in temperature indicating an endothermic process. The negative value of ?Go signifies that the adsorption reaction was spontaneous process. The result indicate that the coir dust residue and modified coir dust extract could be employed as low-cost alternative for the removal of Zn(II) ions from solution. Keywords: Adsorption, coir dust residue, isotherm, NaCl treated coir extract, zinc.
      Issue No: Vol. 6
       
  • Salinity-Alkane Carbon Number (ACN) Relationship of Some Anionic Nonionic
           Surfactant Mixtures

    • Authors: Y. Barakat, Viola Ibrahim
      Abstract: Salinity scans were performed for petroleum sulphonate/eugenol ethoxyate mixtures having the same composition (0.75 mole fraction of witco TRS 10-80 petroleum sulphonate + 0.25 mole fraction of any of the prepared eugenol ethoxylates). Widths of the obtained three-phase (3?) microemulsion regions, were determined and the optimum salinity (S*) values of these anionic/nonionic systems, were calculated at different oil phase alkane carbon numbers (ACN). Phase behaviour diagrams, of the investigated systems, were constructed by plotting the width of the 3? region against oil phase ACN. From the obtained phase maps, the areas of the 3? regions, bounded between the upper and lower phase boundaries (UPB & LPB), were located. Also, the areas bounded between the UPB and LPB fitted curves for the whole ACN range (from hexane to hexadecane, 3?6-16) and that for the preferred ACN (from hexane to nonane, 3?6-9), were determined through computational approach. Linear and polynomial equations were developed to describe the S*-ACN relationship of the investigated systems.Results obtained reveal that more pronounced shift, in the 3? region, to higher ACN was observed when nonionic having longer polyoxyethylene chain was employed. Sulphonate/eugenol ethoxylate mixtures gave 3 ?6-9 regions at a relatively higher salinity ranges if compared with that of sulphonate alone. Such mixtures are more beneficial in surfactant flooding for high salinity reservoirs. Keywords : Eugenol ethoxylates, Petroleum sulphonates, Phase behaviour, Phase map, Surfactant flooding formulation systems.
      Issue No: Vol. 6
       
  • Isolation and Characterization of Palmitic Acid from Ethyl Acetate Extract
           of Root Bark of Terminalia Glaucescens

    • Authors: JS Bulama, SM Dangoggo, ME Halilu, A.I Tsafe, SW Hassan
      Abstract: The aim of this study is to identify and characterized the bioactive compounds from the root bark of the plant. Preliminary phytochemical screening of the root bark extract of Terminalia glaucescens revealed the presence of steroids, terpenoids, saponins, flavonoids, tannins and cardiac glycoside. The plant has wide folk medicinal use in traditional medicine. The air dried root bark was pulverized to powder, subjected to hot extraction (soxhlet) with methanol, and fractionated into n-hexane, ethyl acetate, and n-butanol fractions. Ethyl acetate as bioactive fraction based on sensitivity test was subjected to TLC and column chromatography. The isolated compound was colourless powder, which was further subjected to IR, UV, 13CNMR and 1HNMR for proper characterization and elucidation of the structure. The compound was concluded as palmitic acid.
      Issue No: Vol. 6
       
  • HIV-2 Reverse Transcriptase using Chemical Similarity Process of Reducing
           Viral Attack and Increasing CD4 Counts in HIV-Infected Patients

    • Authors: Jerwin prabu.A, Manimegalai. P, Jenifer. S, Abbirami. S
      Abstract: The aim of this study is to examine the Chemical processes focused to reduce viral attack and increasing CD4 counts, HIV viral load after initiation of combination antiretroviral treatment. However by purchasing and assaying of selected top-scoring compounds from the library active anti-HIV agents are created. Subsequent synthesis and assaying of S10087 analogs proposed by further computational analysis yielded anti- HIV agents. Thus, with the aid of computational tools, it was possible to evolve a false positive into a true active. Antiretroviral treatment–naive, chronically HIV-infected persons (n = 1376 and n = 1605 for each of the 2 cohorts) are untreated. During the observation period (5 months), at least 1 HIV RNA level and 2 CD4 cell counts may be stable. Approximately 35% were nonwhite, and 45% had risk factors. Currently, the data would generally support initiation of HAART in patients with CD4 cell counts more than 350 cells/µl. However, from the strong potential for confounding in observational studies and the lack of adjustment for lead-time bias in many analyses, it is not possible to rule out possible long-term detrimental effects of earlier use of HAART. In chemical process we can use these chemicals and it is possible to reduce the critical bond in HIV virus and increase the amount of CD 4 counts.
      Issue No: Vol. 6
       
  • Dye-Sensitized Solar Cell using Extract of Jacaranda Mimosifolia and
           Salvia Spelendens as a Natural Sensitizer

    • Authors: Leta Takele Menisa, Abi Tadesse Mengesha, Girma Goro Gonfa, Taketel Yohannes Anshebo
      Abstract: Nanocomposites of Sn-Ti oxide were prepared by sol-gel method to use as photo anode for dye sensitized solar cell (DSSC). Crystal size, elemental contents, structural properties and energy band gaps of the as-synthesized powders was examined using XRD, EDX, SEM and UV-Vis spectrophotometer respectively.  A quasi-solid state photo electrochemical solar energy conversion device with I3¯/I¯ redox couple has been constructed and characterized. Natural pigments were also extracted using ethanol, HCl and water solvents from jacaranda mimosifolia and Salvia spelendens to use as sensitizer. Ethanol extract of natural sensitizer absorbs in the visible region. Dye sensitized solar cells were assembled using extracted natural dyes. 8.63% Incident photon to current conversion efficiency (IPCE) at 330 nm was obtained. The photo electrochemical performance of the quasi-solid state DSSCs based on the  ethanol extract of Salvia spelendens showed best photon conversion efficiency with an open circuit voltage (Voc = 266 mV) and short circuit current density (Jsc = 0.1930 mAcm?2) at 100 mWcm-2 white light intensity. Keywords: Sol-gel method, photo electrochemical cell, dye sensitized solar cell, quasi -solid state electrolyte
      Issue No: Vol. 6
       
  • Effect of the Different Preparation Methods on the Characterization and
           the Catalytic activity of the Nano-Structured Cryptomelane Materials

    • Authors: S. Said, M. Riad, M. Helmy, S. Mikhail, L. Khalil
      Abstract: Manganese-based octahedral molecular sieves of the type K-OMS-2 (cryptomelane structure) were prepared either by synproportionation of KMnO4 and Mn2+sulfate salts, in acidic aqueous suspension (reflux method) and or by the reduction  of Mn+7 using benzyl alcohol and CTAB (as template) in neutral medium. The prepared K-OMS-2 materials were characterized using several techniques: X-ray diffraction, Fourier transformer-Infrared & Raman spectroscopy, Transmission electron microscopy, differential & gravimetric thermal analysis, H2-temperature programmed reduction and N2 adsorption-desorption measurements. The results revealed that, the two prepared samples are mainly nano-structured cryptomelane materials (crystallite diameter 9- 32.5 nm.). The obtained K-OMS-2 material on using the sulfate anion (reflux method) has more available lattice oxygen as compared to that prepared by the other method. On using CTAB the obtained cryptomelane material exhibits a high thermal stability. The catalytic activity of the prepared K-OMS-2 cryptomelane samples were studied towards the oxidation reaction of cyclohexane at reaction temperature: 300-400oC. The catalytic activity for K-OMS-2 “neutral” is higher (the conversion increases with the increase in reaction temperature from 27 to 95% successively) with respect to K-OMS-2 ”reflux” (the conversion increases from 30 to 79% successively). Keywords: Cryptomelane, acidic, neutral, lattice oxygen, thermal stability.  
      Issue No: Vol. 6
       
  • The Patronage of Bamboo and Rattan Furniture Products – A Relief of
           Pressure on Wood use in Ghana

    • Authors: Agyei-Boakye Isaac, Quayson Ebenezer, Nutassey Kennedy Newton
      Abstract: The natural high forest of Ghana has depleted greatly due partly to timber logging for primarily furniture and building construction. Almost all the traditional tree species that are solely harvested for furniture production have grown extinct even in the forest reserves. The lesser used species that are in use as replacement are also gradually becoming scarce, its main source of supply to the timber markets being the ‘bush cut.’ Should there be an implementation of the outright ban on the illegal chain saw operation which unarguably, is behind the dominance of the ‘bush cut’ sources, on the timber markets, acquisition of wood would be very difficult to come by. It is anticipated that if the taste for bamboo and cane products is enhanced  and the manufacturing processes made very efficient, the demand for timber (exploitation and depletion) will decline and therefore the supply of timber would also see a corresponding decrease, a very good “omen” for the country to manage the forests at the socially “optimal” level of timber exploitation and trade. The purpose of the study was to ascertain the level of interest of residents of Accra and its environs in furniture products manufactured from local materials other than wood. Using the convenience sampling method 200 people were interviewed using questionnaires. The study revealed that even though the respondents were aware of the negative impacts of wooden furniture production on the environment, more especially on the natural high forest, it is not time yet to develop taste for furniture produced with the other alternative naturally occurring materials such as bamboo and cane. Keywords : traditional tree species, dominance, manufacturing, environment, Rattan, Bamboo,
      Issue No: Vol. 6
       
  • Antiknock Properties and Volatility Criteria of Some Gasoline-Butanol
           Blends

    • Authors: Y. Barakat, Ezis N. Awad, S.M. El Zein, V. Ibrahim
      Abstract: Antinock properties and volatility criteria were studied for all-hydrocarbon gasoline before and after blending with 8 and 12 volume percent n-and iso-butanol. Composition and specifications of the hydrocarbon- base gasoline and the formulated gasoline- oxygenate blends, were determined through gas chromatographic analysis and the standard test methods. The effects of n-and iso-butanol addition on driveability performance and volatility criteria, were studied. Keywords: oxygenated gasoline, gasoline-butanol blend volatility criteria, antiknock properties.  
      Issue No: Vol. 6
       
  • Assessment of Municipal Waste Disposal Methods: A Case Study of Ibadan,
           Nigeria.

    • Authors: Iyanda; Titilope Ayoola, Olaniyi Olatunde A.
      Abstract: In order to prevent health hazards that can occur as a result of inappropriate waste disposal, this study was carried out to identify the various municipal waste disposal methods practiced, and present the methods that are mostly adopted in the South Sahara region. It also analyzed the effects of these methods practiced on individuals and environment, and proffered solutions to the problems facing the populace as a result of these inappropriate methods of waste disposal. The third largest city of Africa located in Nigeria, called Ibadan was used as a case study. Questionnaires of population size 5000 were administered to households in all Local Government Areas of Ibadan. 4500 questionnaires were completely filled and returned. The rating results derived from the survey revealed that the most practiced municipal waste disposal method is open burning. Keywords: Environmental Assessment, Health, Waste Disposal, Open Burning.
      Issue No: Vol. 6
       
  • Refractive Index and Dielectric Properties of TiO2/CuO Core –Shell
           Thin Films

    • Authors: Agbo; P.E
      Abstract: Core-shell metal oxide thin film of the form TiO2/CuO was deposited on a glass substrate using the chemical bath technique. The deposited thin films were subjected to various annealing temperature in order to investigate the effect of thermal annealing on the properties of interest. The films were characterized to study the effect of thermal annealing on refractive index and the dielectric behaviour. Samples of the deposited film were annealed at temperature range of 373K to 673K in step of 100K in order to ascertain the influence of post deposition annealing temperature on the structure, the index of refraction and the dielectric constant. X-ray diffraction technique was used to ascertain the structure of the films, Rutherford backscattering was used to investigate the composition of the film while Scanning electron method was employed in studying the surface morphology of the film. The optical properties were investigated using spectrophotometer analysis. The results showed a reasonable trend between the annealing temperature and the film refractive index and dielectric constant. Keywords: XRD,refractive index, SEM, dielectric constant, photon energy, core-shell
      Issue No: Vol. 6
       
  • Antimicrobial Activity and Quantum Chemical Calculations of
           Pyrazol-2,3-Dihydrothiazole Sugar Derivatives

    • Authors: M. A. Migahed, A. M. Al-Sabagh, E.A. Khamis, M. Abd-EL-Raouf, E. G. Zaki
      Abstract: A number of new [(pyrazol-4-yl) methylene] hydrazono-2,3-dihydrothiazoles, sugar hydrazones, and their N-glycoside derivatives were synthesized. The chemical structures of the synthesized compounds were confirmed by 1H NMR technique. The newly synthesized compounds were tested for their antimicrobial activities and showed moderate to high inhibition activities. Quantum chemistry calculations were used to study the molecular geometry and electronic structure of the selected derivatives. The energy gap between the highest occupied molecular orbital (HOMO)and lowest unoccupied molecular orbital (LUMO) has been calculated using the theoretical computations to reflect the chemical reactivity and kinetic stability of compounds. Keywords: 1H-pyrazole, aminothiazole, ethylchloroacetate, quantum chemical calculations, antimicrobial activity.
      Issue No: Vol. 6
       
  • Characterization of Mixed Solvents of Tetrahydofuran and Acetonitrile for
           Magnesium Ion Battery

    • Authors: Maduelosi N.J, Abia A.A, Nwokobia F.U
      Abstract: Mixed organic electrolytes formed by the combination of Tetrahydrofuran (THF)/ and  Acetonitrile (AN) solvents with Magnesium Perchlorate salt were prepared and characterized for their physico-chemical properties. These properties include density, viscosity, conductivity, dielectric constant, Critical distance for ion pair formation, . The cells of Mg2+ ion containing electrolytic solutions of the binary mixtures of organic solvents were also studied. Jones –Dole viscosity/concentration dependence plots were made, and the ion-ion interaction coefficient (A) and the ion-solvent interaction coefficient (B) were determined. Molar conductivity measurements investigated at 250c demonstrated that the mixed systems exhibit a wide electrochemical stability window than the pure solvents. The properties of the mixed electrolytes were affected by ion-solvent and solvent-solvent interactions. The results have been interpreted on the basis of the intermolecular interactions among the component molecules of the systems. The temperatures studied show that the battery remain stable even at high temperatures. The mixing ratio of the organic solvents for optimal battery performance is established to be between 15-25%THF for the  system studied. Key words: Battery,Magnesium ions, conductivity,viscosity,density, voltage
      Issue No: Vol. 6
       
 
 
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