Subjects -> CHEMISTRY (Total: 1001 journals)
    - ANALYTICAL CHEMISTRY (59 journals)
    - CHEMISTRY (726 journals)
    - CRYSTALLOGRAPHY (23 journals)
    - ELECTROCHEMISTRY (28 journals)
    - INORGANIC CHEMISTRY (45 journals)
    - ORGANIC CHEMISTRY (49 journals)
    - PHYSICAL CHEMISTRY (71 journals)

CHEMISTRY (726 journals)                  1 2 3 4 | Last

Showing 1 - 200 of 735 Journals sorted alphabetically
Accounts of Materials Research     Hybrid Journal  
Accreditation and Quality Assurance: Journal for Quality, Comparability and Reliability in Chemical Measurement     Hybrid Journal   (Followers: 36)
ACS Applied Polymer Materials     Hybrid Journal   (Followers: 15)
ACS Catalysis     Hybrid Journal   (Followers: 78)
ACS Chemical Neuroscience     Hybrid Journal   (Followers: 25)
ACS Combinatorial Science     Hybrid Journal   (Followers: 25)
ACS Macro Letters     Hybrid Journal   (Followers: 34)
ACS Materials Letters     Open Access   (Followers: 4)
ACS Medicinal Chemistry Letters     Hybrid Journal   (Followers: 49)
ACS Nano     Hybrid Journal   (Followers: 452)
ACS Photonics     Hybrid Journal   (Followers: 19)
ACS Symposium Series     Full-text available via subscription   (Followers: 3)
ACS Synthetic Biology     Hybrid Journal   (Followers: 40)
Acta Chemica Iasi     Open Access   (Followers: 8)
Acta Chemica Malaysia     Open Access  
Acta Chimica Slovaca     Open Access   (Followers: 4)
Acta Chimica Slovenica     Open Access   (Followers: 2)
Acta Chromatographica     Full-text available via subscription   (Followers: 9)
Acta Facultatis Medicae Naissensis     Open Access   (Followers: 1)
Acta Metallurgica Sinica (English Letters)     Hybrid Journal   (Followers: 10)
Acta Scientifica Naturalis     Open Access   (Followers: 3)
adhäsion KLEBEN & DICHTEN     Hybrid Journal   (Followers: 9)
Adhesion Adhesives & Sealants     Hybrid Journal   (Followers: 10)
Adsorption Science & Technology     Open Access   (Followers: 9)
Advanced Electronic Materials     Hybrid Journal   (Followers: 7)
Advanced Functional Materials     Hybrid Journal   (Followers: 81)
Advanced Journal of Chemistry, Section A     Open Access   (Followers: 15)
Advanced Journal of Chemistry, Section B     Open Access   (Followers: 14)
Advanced Science Focus     Free   (Followers: 7)
Advanced Theory and Simulations     Hybrid Journal   (Followers: 5)
Advanced Therapeutics     Hybrid Journal   (Followers: 1)
Advances in Chemical Engineering and Science     Open Access   (Followers: 108)
Advances in Chemical Science     Open Access   (Followers: 50)
Advances in Chemistry     Open Access   (Followers: 39)
Advances in Chemistry     Full-text available via subscription   (Followers: 6)
Advances in Colloid and Interface Science     Full-text available via subscription   (Followers: 21)
Advances in Drug Research     Full-text available via subscription   (Followers: 27)
Advances in Environmental Chemistry     Open Access   (Followers: 11)
Advances in Enzyme Research     Open Access   (Followers: 13)
Advances in Fluorine Science     Full-text available via subscription   (Followers: 8)
Advances in Fuel Cells     Full-text available via subscription   (Followers: 20)
Advances in Heterocyclic Chemistry     Full-text available via subscription   (Followers: 11)
Advances in Materials Physics and Chemistry     Open Access   (Followers: 35)
Advances in Nanoparticles     Open Access   (Followers: 20)
Advances in Organometallic Chemistry     Full-text available via subscription   (Followers: 20)
Advances in Polymer Science     Hybrid Journal   (Followers: 54)
Advances in Protein Chemistry     Full-text available via subscription   (Followers: 19)
Advances in Protein Chemistry and Structural Biology     Full-text available via subscription   (Followers: 22)
Advances in Quantum Chemistry     Full-text available via subscription   (Followers: 7)
Advances in Science and Technology     Full-text available via subscription   (Followers: 17)
Aerosol Science and Engineering     Hybrid Journal  
African Journal of Bacteriology Research     Open Access  
African Journal of Chemical Education     Open Access   (Followers: 6)
African Journal of Pure and Applied Chemistry     Open Access   (Followers: 7)
Aggregate     Open Access   (Followers: 3)
Agrokémia és Talajtan     Full-text available via subscription   (Followers: 3)
Al-Kimia : Jurnal Penelitian Sains Kimia     Open Access  
Alchemy : Journal of Chemistry     Open Access   (Followers: 5)
Alchemy : Jurnal Penelitian Kimia     Open Access   (Followers: 2)
Alkaloids: Chemical and Biological Perspectives     Full-text available via subscription   (Followers: 2)
Alotrop     Open Access  
AMB Express     Open Access   (Followers: 1)
Ambix     Hybrid Journal   (Followers: 3)
American Journal of Biochemistry and Biotechnology     Open Access   (Followers: 71)
American Journal of Biochemistry and Molecular Biology     Open Access   (Followers: 24)
American Journal of Chemistry     Open Access   (Followers: 41)
American Journal of Plant Physiology     Open Access   (Followers: 13)
Analyst     Full-text available via subscription   (Followers: 40)
Analytical Science Advances     Open Access   (Followers: 2)
Angewandte Chemie     Hybrid Journal   (Followers: 234)
Angewandte Chemie International Edition     Hybrid Journal   (Followers: 352)
Annales Universitatis Mariae Curie-Sklodowska, sectio AA – Chemia     Open Access   (Followers: 1)
Annals of Clinical Chemistry and Laboratory Medicine     Open Access   (Followers: 8)
Annual Reports in Computational Chemistry     Full-text available via subscription   (Followers: 4)
Annual Reports Section A (Inorganic Chemistry)     Full-text available via subscription   (Followers: 6)
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: 13)
Annual Review of Food Science and Technology     Full-text available via subscription   (Followers: 16)
Antiviral Chemistry and Chemotherapy     Open Access   (Followers: 2)
Applied Organometallic Chemistry     Hybrid Journal   (Followers: 12)
Applied Spectroscopy     Full-text available via subscription   (Followers: 27)
Applied Surface Science     Hybrid Journal   (Followers: 33)
Arabian Journal of Chemistry     Open Access   (Followers: 6)
ARKIVOC     Open Access   (Followers: 1)
Asian Journal of Applied Chemistry Research     Open Access   (Followers: 2)
Asian Journal of Biochemistry     Open Access   (Followers: 3)
Asian Journal of Chemical Sciences     Open Access   (Followers: 1)
Asian Journal of Chemistry and Pharmaceutical Sciences     Open Access   (Followers: 2)
Asian Journal of Physical and Chemical Sciences     Open Access   (Followers: 3)
Atomization and Sprays     Full-text available via subscription   (Followers: 8)
Australian Journal of Chemistry     Hybrid Journal   (Followers: 7)
Autophagy     Hybrid Journal   (Followers: 7)
Avances en Quimica     Open Access  
Biochemical Pharmacology     Hybrid Journal   (Followers: 11)
Biochemistry     Hybrid Journal   (Followers: 483)
Biochemistry Insights     Open Access   (Followers: 7)
Biochemistry Research International     Open Access   (Followers: 6)
BioChip Journal     Hybrid Journal  
Bioinorganic Chemistry and Applications     Open Access   (Followers: 11)
Biointerface Research in Applied Chemistry     Open Access   (Followers: 3)
Biointerphases     Open Access   (Followers: 1)
Biology, Medicine, & Natural Product Chemistry     Open Access   (Followers: 4)
Biomacromolecules     Hybrid Journal   (Followers: 27)
Biomass Conversion and Biorefinery     Partially Free   (Followers: 11)
Biomedical Chromatography     Hybrid Journal   (Followers: 6)
Biomolecular NMR Assignments     Hybrid Journal   (Followers: 4)
BioNanoScience     Partially Free   (Followers: 6)
Bioorganic & Medicinal Chemistry     Hybrid Journal   (Followers: 214)
Bioorganic & Medicinal Chemistry Letters     Hybrid Journal   (Followers: 88)
Bioorganic Chemistry     Hybrid Journal   (Followers: 10)
Biopolymers     Hybrid Journal   (Followers: 18)
Biosensors     Open Access   (Followers: 4)
Biotechnic and Histochemistry     Hybrid Journal   (Followers: 1)
Bitácora Digital     Open Access  
Boletin de la Sociedad Chilena de Quimica     Open Access  
Bulletin of Institute of Chemistry and Chemical Technology, Mongolian Academy of Sciences     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: 26)
Bulletin of the Korean Chemical Society     Hybrid Journal   (Followers: 1)
C - Journal of Carbon Research     Open Access   (Followers: 5)
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: 13)
Canadian Mineralogist     Full-text available via subscription   (Followers: 7)
Carbohydrate Polymer Technologies and Applications     Open Access   (Followers: 3)
Carbohydrate Polymers     Hybrid Journal   (Followers: 13)
Carbohydrate Research     Hybrid Journal   (Followers: 26)
Carbon     Hybrid Journal   (Followers: 76)
Catalysis Reviews: Science and Engineering     Hybrid Journal   (Followers: 9)
Catalysis Science and Technology     Hybrid Journal   (Followers: 13)
Catalysis Surveys from Asia     Hybrid Journal   (Followers: 4)
Catalysts     Open Access   (Followers: 14)
Cell Reports Physical Science     Open Access  
Cellulose     Hybrid Journal   (Followers: 17)
Cereal Chemistry     Full-text available via subscription   (Followers: 6)
ChemBioEng Reviews     Full-text available via subscription   (Followers: 3)
ChemCatChem     Hybrid Journal   (Followers: 11)
Chemical and Engineering News     Free   (Followers: 24)
Chemical Bulletin of Kazakh National University     Open Access  
Chemical Communications     Full-text available via subscription   (Followers: 88)
Chemical Engineering Research and Design     Hybrid Journal   (Followers: 28)
Chemical Physics Letters : X     Open Access   (Followers: 4)
Chemical Research in Chinese Universities     Hybrid Journal   (Followers: 4)
Chemical Research in Toxicology     Hybrid Journal   (Followers: 25)
Chemical Reviews     Hybrid Journal   (Followers: 266)
Chemical Science     Open Access   (Followers: 44)
Chemical Science International Journal     Open Access   (Followers: 1)
Chemical Technology     Open Access   (Followers: 71)
Chemical Vapor Deposition     Hybrid Journal   (Followers: 5)
Chemie in Unserer Zeit     Hybrid Journal   (Followers: 56)
Chemie-Ingenieur-Technik (Cit)     Hybrid Journal   (Followers: 23)
ChemInform     Hybrid Journal   (Followers: 9)
Chemistry     Open Access  
Chemistry & Biodiversity     Hybrid Journal   (Followers: 7)
Chemistry & Biology     Full-text available via subscription   (Followers: 31)
Chemistry & Industry     Full-text available via subscription   (Followers: 8)
Chemistry - A European Journal     Hybrid Journal   (Followers: 223)
Chemistry - An Asian Journal     Hybrid Journal   (Followers: 20)
Chemistry Africa : A Journal of the Tunisian Chemical Society     Hybrid Journal  
Chemistry and Materials Research     Open Access   (Followers: 24)
Chemistry Central Journal     Open Access   (Followers: 5)
Chemistry Education Research and Practice     Free   (Followers: 8)
Chemistry Education Review     Open Access   (Followers: 5)
Chemistry in Education     Open Access   (Followers: 9)
Chemistry Letters     Full-text available via subscription   (Followers: 49)
Chemistry of Heterocyclic Compounds     Hybrid Journal   (Followers: 4)
Chemistry of Materials     Hybrid Journal   (Followers: 337)
Chemistry of Natural Compounds     Hybrid Journal   (Followers: 10)
Chemistry World     Full-text available via subscription   (Followers: 20)
Chemistry-Didactics-Ecology-Metrology     Open Access   (Followers: 1)
ChemistryOpen     Open Access   (Followers: 1)
ChemistrySelect     Hybrid Journal  
Chemistry–Methods     Open Access   (Followers: 2)
Chemkon - Chemie Konkret, Forum Fuer Unterricht Und Didaktik     Hybrid Journal  
ChemNanoMat     Hybrid Journal   (Followers: 1)
Chemoecology     Hybrid Journal   (Followers: 3)
Chemometrics and Intelligent Laboratory Systems     Hybrid Journal   (Followers: 14)
Chemosensors     Open Access   (Followers: 1)
ChemPhotoChem     Hybrid Journal  
ChemPhysChem     Hybrid Journal   (Followers: 14)
ChemPlusChem     Hybrid Journal   (Followers: 2)
Chempublish Journal     Open Access   (Followers: 1)
ChemSystemsChem     Hybrid Journal   (Followers: 2)
ChemTexts     Hybrid Journal   (Followers: 1)
CHIMIA International Journal for Chemistry     Open Access   (Followers: 2)
Chinese Journal of Chemistry     Hybrid Journal   (Followers: 6)
Chinese Journal of Polymer Science     Hybrid Journal   (Followers: 13)
Chromatographia     Hybrid Journal   (Followers: 22)
Chromatography     Open Access   (Followers: 3)
Chromatography Research International     Open Access   (Followers: 5)
Ciencia     Open Access   (Followers: 1)
Clay Minerals     Hybrid Journal   (Followers: 9)
Cogent Chemistry     Open Access   (Followers: 3)
Colloid and Interface Science Communications     Open Access  
Colloid and Polymer Science     Hybrid Journal   (Followers: 12)
Colloids and Interfaces     Open Access  
Colloids and Surfaces B: Biointerfaces     Hybrid Journal   (Followers: 8)
Combinatorial Chemistry & High Throughput Screening     Hybrid Journal   (Followers: 4)
Combustion Science and Technology     Hybrid Journal   (Followers: 24)
Comments on Inorganic Chemistry: A Journal of Critical Discussion of the Current Literature     Hybrid Journal   (Followers: 2)

        1 2 3 4 | Last

Similar Journals
Journal Cover
Cellulose
Journal Prestige (SJR): 1.047
Citation Impact (citeScore): 4
Number of Followers: 17  
 
  Hybrid Journal Hybrid journal (It can contain Open Access articles)
ISSN (Print) 1572-882X - ISSN (Online) 0969-0239
Published by Springer-Verlag Homepage  [2658 journals]
  • GQD embedded bacterial cellulose nanopaper based multi-layered filtration
           membranes assembly for industrial dye and heavy metal removal in
           wastewater

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      Abstract: The graphene based materials in water pollutant treatment have recently gained significant attention due to their high surface area, high mechanical strength and tuneable surface chemistry. However, the relatively high cost, poor hydrophobicity, low adsorption capacity, and recyclability limit their practical application. Here in, driven by need, we report a simple approach for the synthesis of graphene quantum dots (GQDs) via pyrolysis, preferred because of high controllability and fewer defects over chemical exfoliation methods. The synthesized GQDs are further embedded on bacterial cellulose nanopaper (BCN) and characterized using spectroscopy and microscopy techniques. Furthermore, the well-ordered multi-layered GQD embedded BCN based filtration assembly is designed and developed for treatment of water pollutants and industrial dye wastewater. The multi-layered GQD embedded BCN based filtration assembly is validated by purifying industrial dye and heavy metal (Hg2+, Pb2+) with removal efficiency of 99.6% and 97%, respectively. Our multi-layered filtration assembly demonstrated significant membrane regeneration capacity until six cycles. The isotherm model also showed an appropriate fit exhibiting good adsorption behaviour. Our multi-layered filtration assembly can be established as a promising filtration assembly for inexpensive, efficient and low energy applications in wastewater treatment. Graphic abstract
      PubDate: 2021-11-01
       
  • On the role of N-methylmorpholine-N-oxide (NMMO) in the generation of
           elemental transition metal precipitates in cellulosic materials

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      Abstract: Several literature reports describe the role of aqueous solutions of N-methylmorpholine-N-oxide monohydrate (NMMO) as a suitable medium for the generation of transition metal (nano)particles in or on cellulosic materials and further elaborate its role as a co-reactant of the transition metal salts that are reduced to the elemental metal. However, this would assign NMMO the role of a reductant, which is in contradiction of its obvious oxidative nature. In the present study, the exemplary cases of silver, gold, and platinum salts as the precursors of the respective metal (nano)particles in aqueous NMMO/cellulose mixtures were investigated. Naturally, NMMO did not act as a reducing agent in any case—this role was taken over by the frequently used NMMO stabilizer propyl gallate, or by cellulose itself, into which carbonyl and carboxyl groups were introduced. Also, hypochlorite—produced intermediately from chloride ions and subsequently undergoing disproportionation into chloride and chlorate—or transient N-methylene(morpholinium) ions generated from NMMO, which are in turn oxidized to formyl morpholide, can act as the corresponding reductants while the metal ions are reduced, depending on the reaction conditions. Apart from providing interesting mechanistic insights, the study points to the importance of a precise description of the composition of the chemical systems used, as well as the importance of seemingly inert auxiliaries, which turned out to be essential co-reactants in the metal (nano)particle generation. Graphic abstract
      PubDate: 2021-11-01
       
  • Development and characterization of bentonite-gum arabic composite as
           novel highly-efficient adsorbent to remove thorium ions from aqueous media
           

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      Abstract: Elimination of radioactive ions from wastewater using powerful adsorbents is of great importance for reducing the environmental pollution. Within this context, Bentonite (BNT)-Gum Arabic (GA) composite was developed as a new adsorbent to excellently eliminate Th(IV) ions from aqueous media. The produced composite adsorbent was examined by FTIR and SEM/EDX techniques. The effects of main empirical parameters on the adsorption efficiency were optimized by factorial design analysis. The maximum elimination capacity of BNT-GA was determined as 885.4 mg g−1 at pH 4.5, in 30 min, and 24 °C. Thermodynamic studies showed that Th(IV) adsorption progressed exothermically and the spontaneity of the process was lessened with the increase in temperature. Kinetic findings exposed that the adsorption mechanism fits perfectly with the pseudo-second-order (PSO) model. A 96% part of the adsorbed Th(IV) ions was recovered from the composite adsorbent using 1.0 M HCl. The produced composite revealed remarkable adsorption/desorption efficiency even after 7 cycles. All results show that the prepared BNT-GA compound can be used for the effective exclusion of Th(IV) ions from wastewater due to its advantageous properties such as great elimination capacity, cost-effectiveness, and facile preparation.
      PubDate: 2021-11-01
       
  • Fabrication of hierarchical porous MgO/cellulose acetate hybrid membrane
           with improved antifouling properties for tellurium separation

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      Abstract: Considerable toxic tellurium-containing wastewater has been discharged into water environment and constantly accumulates, due to the widespread applications but low utilization of tellurium, causing irreversible harm to the environment and human health, thus it is crucial to find an efficient strategy for tellurium separation. Herein, hierarchical porous magnesium oxide modified cellulose acetate membranes (MgO@CAM) were prepared via a facile physical blending and phase inversion method for tellurium separation. Diverse characterization methods and batch separation experiments were conducted to investigate the morphological structure of MgO@CAM, tellurium separation mechanism, and the separation behavior under different influencing factors. The results exhibit that MgO@CAM has a hierarchical porous structure and a hydroxyl-rich surface, which facilitates the separation of tellurium. Besides, MgO@CAM reveals eligible regeneration performance, good stability and thermal stability due to the hydrogen bonding and skeletal structure of cellulose acetate. The study on the effect of pH suggests that an acidic environment is more conducive to the separation of tellurium by MgO@CAM, and the prepared membranes show outstanding separation efficiency of tellurium, with a maximum of 97.6%. Furthermore, the membranes also achieve satisfactory separation efficiency of tellurium in the presence of multiple coexisting ions. Thomas dynamics indicate the practical application of MgO@CAM in tellurium separation. More importantly, prominent hydrophilic enables MgO@CAM to demonstrate excellent antifouling performance. Therefore, the preparation of hierarchical porous MgO@CAM provides an efficient and economic strategy for tellurium separation in wastewater and has promising applications in water treatment. Graphic abstract
      PubDate: 2021-11-01
       
  • Robust paper-based materials for efficient oil–water emulsion
           separation

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      Abstract: Developing a feasible and efficient separation membrane for the purification of emulsified oily wastewater is challenging due to the critical limitations of serious fouling during membrane preparation. Herein, underwater superoleophobic paper-based materials with high wet strength were prepared by low cost and green papermaking technology. The fibrillation of cellulose fibers was achieved by beating to optimize the pore structure of paper sheets. Simple modification of paper sheets with 1,2,3,4-butanetetracarboxylic acid significantly improves the surface hydrophilicity and the wet strength through the crosslinking reaction between fibers. The maximum underwater oil contact angle and wet strength of the modified paper sheets are high up to 167.8°and 36.5 N·m/g, respectively. The water flux can be adjusted in the range of 25.8 L m−2 h−1–4920 L m−2 h−1 by controlling the average pore size from 6.64 μm to 18.9 μm. Lower pore size and higher carboxyl content of the paper-based materials are beneficial to improve the oil rejection, which can reach more than 99.3% even for submicron emulsified oils. Most of the paper sheets achieve efficient oil–water separation although the average pore size is remarkably larger than the emulsified oil droplet. The reason can be attributed to the zigzag pore structure of paper sheets, which is favorable to form liquid bridge on the surface as well as collision demulsification in the Z-direction channel, thereby promoting the mechanical interception effects. The low-cost, eco-friendly, easily-manufactured and highly efficient paper-based separation materials possess wide applications in oily wastewater treatment.
      PubDate: 2021-11-01
       
  • Environmental method for preparation of higher color strength dyeing
           cotton fabrics with colored nanosilica pigment

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      Abstract: Colored wastewater discharge into the water system would pose a severe threat to human health and aquatic life. It is critical to enhance dye utilization and reduce dye discharge in the textile industry. In this work, a novel colored silica nanosphere was designed as pigment to dye cotton fabrics and could be recycled in the dyeing process. The worm-like hydrophilic porous silica (WHMS) nanospheres possess a large specific surface area of 968.61 m2/g, an average size of 300 nm, and strong electronegativity. The WHMS-dye nanosphere was fabricated through the adsorption of rhodamine B (RB) and methylene blue (MB) onto WHMS nanospheres. The adsorption capacities of WHMS nanospheres towards RB and MB were above 500 mg/g. It demonstrated that the prepared WHMS-dye nanospheres possessed good stability and coloration performance on the cotton fabrics, originating from the enrichment of dyes on the WHMS nanospheres. The color strength of colored nanospheres-dyed cotton fabrics is deeper compared with the pure dye. Moreover, the dyed cotton fabrics show satisfactory color fastness and hand feel. The colored silica nanospheres could be reused for the next dyeing process to reduce dyes discharge. This work shows that WHMS-dye nanospheres may be used as an environmentally sound pigment for dyeing cotton fabrics to avoid a large amount of dyes discharge. Graphic abstract
      PubDate: 2021-11-01
       
  • Micro/nanostructured lignonanocellulose obtained from steam-exploded
           sugarcane bagasse

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      Abstract: This work demonstrates the isolation of lignocellulose micro-nanofibrils, nanocrystals and nanospheres from steam-exploded sugarcane bagasse (SEB). First, steam-explosion was carried out in sugarcane bagasse at 195 °C for 7.5 and 15 min (SEB-7.5 and SEB-15). Untreated sugarcane bagasse was also pretreated by mechanical refining (MRB) in a PFI mill for comparison. Then, SEB and MRB fibers were subjected to alkaline delignification, hypochlorite bleaching for 60 or 180 min (HB60 and HB180), enzymatic hydrolysis (endoglucanase), and high-pressure homogenization. The resulting materials were characterized regarding chemical composition by high-performance liquid chromatography, width and morphology by transmission electron microscopy, crystallinity by X-ray powder diffraction and aspect ratio (length/diameter) by rheology. Levels of glucans (mostly cellulose), hemicelluloses and lignin were: 53.8%, 19.7% and 11.6% in MRB-HB180; 87.8%, < 0.1% and 7.2% in SEB-7.5-HB60; 84.3%, < 0.1% and 4.8% in SEB-7.5-HB180, 85.9%, < 0.1% and 8.4% in SEB-15-HB60; and 82.2%, < 0.1% and 5% in SE-15-HB180, respectively. Aspect ratios and crystallinity indexes were similar among all groups (~ 100 and ~ 73%, respectively), except for SE-15-HB180 (~ 78.5 and 77%, respectively). MRB-HB180 and SE-15 (HB60 and HB180) had the lowest fiber widths (< 20 nm) with the presence of nanocrystals in SE-15-HB180, while in the SE-7.5 (HB60 and HB180), fiber widths were greater than 50 nm with the presence of lignin nanospheres in SE-7.5-HB60. Hence, lignocellulose nanomaterials with aspect ratios ranging from micro/nanofibers to nanocrystals were isolated from SEB using a cost-effective production process. Graphic abstract
      PubDate: 2021-11-01
       
  • Bacterial cellulose based facial mask with antioxidant property and high
           moisturizing capacity

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      Abstract: Bacterial cellulose (BC) produced by certain bacteria has the potential to be used in many different areas. Despite its advantageous properties compared to plant cellulose, such as high purity, mechanical strength, nanofiber mesh structure, and high-water holding capacity, its production through a biotechnological process prevents it from competing with plant counterparts in terms of cost-effectiveness. Therefore, studies have focused on the development of culture media with cost-effective BC production methods and the production of high value-added products from BC. In this study, it was aimed to develop a taurine-loaded moisturizing facial mask with antioxidant properties based on BC’s high-water retention and chemical retention capacity. BC facial mask samples were characterized by Scanning Electron Microscopy (SEM) imaging, Fourier Transform Infrared (FTIR) Spectroscopy, Differential Scanning Calorimetry (DSC), Liquid Chromatography–Mass spectrometry (LC–MS), microbial and mechanical stability tests, as well as cytotoxicity tests. According to our results, produced facial mask samples did not show any cytotoxic effect on human keratinocyte (HS2) or mouse fibroblast (L-929) cell lines; it has high thermal stability, which makes it suitable for different sterilization techniques including sterilization by heat treatment. Taurine release (over 2 µg/mL in 5 min) and microbial stability tests (no bacterial growth observed) of packaged products kept at 40 and 25 °C for 6 months have shown that the product preserves its characteristics for a long time. In conclusion “bacterial cellulose-based facial masks" are suitable for use as a facial mask, and they can be used for moisturizing and antioxidant properties by means of taurine.
      PubDate: 2021-11-01
       
  • Effect of ultrasonication on the size distribution and stability of
           cellulose nanocrystals in suspension: an asymmetrical flow field-flow
           fractionation study

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      Abstract: Cellulose nanocrystals (CNCs) are bio-based building blocks for sustainable advanced materials with prospective applications in polymer composites, emulsions, electronics, sensors, and biomedical devices. However, their high surface area-to-volume ratio promotes agglomeration, which restrains their performance in size-driven applications, thereby hindering commercial CNC utilization. In this regard, ultrasonication is commonly applied to disperse CNCs in colloidal suspensions; however, ultrasonication methodology is not yet standardized and knowledge of the effects of ultrasound treatments on CNC size distribution is scarce. The major goals of this study were attributed to targeted breakage of CNC agglomerates and clusters by ultrasound. The evolution of particle size distribution and potential de-sulfation by ultrasonication as well as the long-term stability of ultrasonicated CNC suspensions were investigated. Colloidal suspensions of sulfated CNCs were isolated from cotton α-cellulose. Effects of ultrasonication on particle size distribution were determined by asymmetrical flow field-flow fractionation (AF4) coupled with on-line multi-angle light scattering and ultraviolet spectroscopy. These results were complemented with off-line dynamic light scattering. High ultrasound energy densities facilitated cumulative dispersion of CNC clusters. Consequently, the mean rod length decreased logarithmically from 178.1 nm at an ultrasound energy input of 2 kJ g−1 CNC to 141.7 nm (− 20%) at 40 kJ g−1 CNC. Likewise, the hydrodynamic diameter of the particle collective decreased logarithmically from 94.5 to 73.5 nm (− 22%) in the same processing window. While the rod length, below which 95 wt% of the CNCs were found, decreased from 306.5 to 231.8 nm (− 24%) from 2 to 40 kJ g−1 CNC, the shape factor of the main particle fraction ranged from 1.0 to 1.1, which indicated a decreasing number of dimers and clusters in the particle collective. In summary, progressing ultrasonication caused a shift of the particle length distribution to shorter particle lengths and simultaneously induced narrowing of the distribution. The suspension’s electrical conductivity concurrently increased, which has been attributed to faster diffusion of smaller particles and exposure of previously obscured surface charges. Colloidal stability, investigated through electrical AF4 and electrophoretic light scattering, was not affected by ultrasonication and, therefore, indicates no de-sulfation by the applied ultrasound treatment. Occurrence of minor CNC agglomeration at low ultrasound energy densities over the course of 6 months suggest the effect was not unmitigatedly permanent.
      PubDate: 2021-11-01
       
  • Facile microwave assisted flame retardant treatment for cotton fabric
           using a biobased industrial byproduct: phytic acid

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      Abstract: A single-step, solvent-free microwave-assisted technique for flame retardant (FR) cotton fabric using a bio-based FR agent, phytic acid is presented. The effects of microwave power and irradiation time on FR characteristics of cotton are investigated. Self-extinguishing cotton fabric with char length of 79 mm and no afterflame is achieved within 4 min of 600 W microwave irradiation whereas a treatment time of as long as 45 min is needed in conventional heating method to achieve the same level of weight add-on or FR performance. The cotton fabric treated with phytic acid in the microwave also exhibits 90% retention of tear strength. Comprehensive characterization of the phytic acid treated cotton fabric using scanning electron microscope (SEM), elemental analysis, thermal gravimetric analysis (TGA), and microscale combustion calorimetry (MCC) correlated with reaction condition allowed the formulation of generalized guidelines applicable for microwave assisted cellulose phosphorylation. The FR mechanism study shows that phytic acid is covalently attached to cellulose and as an acid source, contributes to intumescent char formation during combustion. Graphic abstract
      PubDate: 2021-11-01
       
  • An environmentally-friendly sandwich-like structured nanocoating system
           for wash durable, flame retardant, and hydrophobic cotton fabrics

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      Abstract: Surface modification is a main approach for natural polymers to gain flame retardancy. Developing a green coating system to endow natural polymers with flame retardancy and wash-durability is extremely challenging. Herein, a sandwich-like structured nanocoating system with mutual restricted network through electrostatic interaction, hydrogen bonding, and chemical bonding were designed via multi-layered coating and UV curing. The coated natural cotton fabrics demonstrated exellent flame retardancy, wash durability, and hydrophobicity. The chemicals involved include montmorillonite (MMT), ammonium polyphosphate (APP), acrylated polyurethane (PU), branched polyethylenimine (bPEI), and polydimethylsiloxane (PDMS). The concentration of bPEI governed the wash durability of the coated fabrics, and those samples with a higher concentration of bPEI possessed better wash durability. Meanwhile, bPEI served as a flammable resource to deteriorate the flame retardant performance. The systematic evaluations of the coated fabrics after washing demonstrated that this coating system can maintain balanced wash durability and flame retardancy. Graphic abstract
      PubDate: 2021-11-01
       
  • Preparation of cellulose-based fluorescent materials as coating pigment by
           use of DMSO/DBU/CO2 system

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      Abstract: A series of cellulose-based fluorescent materials are prepared under relative mild conditions by use of the DMSO/1,8-diazabicyclo[5.4.0]undec-7-ene (DBU)/CO2 system to utilize as coating pigments. Through the observation under 365 nm UV light, the cellulose-based fluorescent materials exhibit good fluorescence response and bright color. Furthermore, due to the limitation of the molecular skeleton of cellulose, the intrinsic aggregation caused quenching phenomenon commonly existed in conventional organic fluorescent pigments can be effectively inhibited, which is very helpful to retain good fluorescence response in epoxy-based coating material and its coating films. Moreover, the addition of cellulose-based fluorescent materials also increases the mechanical properties of the coating film. The increase of tensile strength and tensile modulus respectively reaches ~39% and ~66%. Solvent resistance and thermal property of the coating films generally remain unchanged. The fabrication of cellulose-based fluorescent materials in DMSO/DBU/CO2 system provides a feasible way to develop the functional application of cellulose. Graphic abstract
      PubDate: 2021-11-01
       
  • Superhydrophobic materials with good oil/water separation and
           self-cleaning property

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      Abstract: A simple, efficient, and economical method was developed to fabricate superhydrophobic surfaces on various substrates, including wood, bamboo, cotton, filter paper, sponge, glass, textile, and copper. This method involves synthesizing a two-component modifier solution consisting of SiO2 nanoparticles combined with poly(methylhydrogen)siloxane (PMHS) modification. The superhydrophobicity of the coated surfaces was created by PMHS combined with SiO2 nanoparticles to construct a rough hierarchical structure on the surface of the substrate. All superhydrophobic surfaces were maintained at a relative humidity of 50% for 30 days in an indoor environment and subsequently, the superhydrophobic surfaces were kept minus 20 °C for 24 h. It was confirmed that these surfaces exhibited excellent self-cleaning, oil/water separation, and elimination of underwater oil properties. The method for fabricating superhydrophobic materials proposed in this study will have great potential to prepare large-scale superhydrophobic surfaces for use in ancient building protection. Graphic abstract
      PubDate: 2021-11-01
       
  • Non-freezing water sorbed on microcrystalline cellulose studied by
           high-resolution thermogravimetric analysis

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      Abstract: Knowing the nature of water-cellulose interactions is a key factor in understanding cellulose properties and developing new processing strategies. The emergence of new advanced materials based on nanocelluloses requires more precise methods to study these systems. Here we described the study of water-cellulose interaction by high-resolution thermogravimetric analysis (TGA), comparing dynamic and auto stepwise methods. Auto stepwise method was able to identify with precision three different types of non-freezing water, which we denoted as, (I) weakly bound water, (II) intermediate and (III) strongly bound water. The Ozawa-Flynn-Wall method was used to estimate the activation energy of strongly bound water desorption, Ea average = 50.45 kJ.mol−1 and the cellulose degradation energy, Ea average = 143.18 kJ.mol−1. The results obtained provide a new knowledge about the interaction between water and cellulose since other techniques such as DSC are not sensitive to non-freezing bound water. Graphic
      PubDate: 2021-11-01
       
  • Pretreatment of corn stover by acidic and basic choline chloride solutions
           for enzymatic hydrolysis

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      Abstract: As a cheap, biodegradable, and nontoxic chemical, choline chloride (ChCl) is widely used in animal feed. In this study, acid and alkali catalyzed ChCl pretreatments of corn stover (CS) were investigated. Compared with single aqueous ChCl pretreatment, H2SO4 acidified aqueous ChCl pretreatment was more effective in removing lignin (69.5%) and xylan (84.9%). NaOH alkalified aqueous ChCl pretreatment demonstrated better performance of delignification (76.8%) but weaker capability of removing xylan (46.2%) than acidified aqueous ChCl pretreatment. Following enzymatic digestibility of pretreated CS, glucose yield from acidified ChCl pretreatment was 72.1%, significantly lower than that of alkalified ChCl pretreatment (89.4%). However, the highest glucose yield of 98.6% resulted from solitary alkali pretreatment. Correlation studies between change in physico-chemical properties of pretreated solids and corresponding enzymatic digestibility indicated high delignification and bigger cellulose crystallite size were mainly responsible for high enzymatic hydrolysis efficiency. Additionally, the properties of extracted lignin from single and combined pretreatments with ChCl and alkali or acid were analyzed. Acidified ChCl pretreatment increased, whereas alkaline ChCl pretreatment decreased molecular weight and phenolic hydroxyl groups of separated lignin in comparison to individual acid and alkali pretreatment. These findings would provide useful information in understanding biomass pretreatments with aqueous ChCl.
      PubDate: 2021-11-01
       
  • Application of enzyme technology in biopulping and biobleaching

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      Abstract: Owing to the rapid development of biotechnology, enzymes are being used more frequently in the manufacturing industry, especially in the pulp and paper industry. Compared with traditional pulping, biopulping has the advantage of requiring mild reaction conditions, which makes it more eco-friendly and faster than other methods. When enzymes are combined with other pulping technologies, maximum pulping efficiency can be ensured and pollution could be reduced. However, to maximize pulping efficiency, control pulping costs, and achieve the best quality paper, enzymatic methods are often combined with other pulping technologies. Therefore, enzyme production costs for papermaking remains a problem to be addressed in future research. Graphic abstract
      PubDate: 2021-11-01
       
  • Lignocellulose nanofiber incorporated N-TiO2 for wound dressing

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      Abstract: Lignocellulose nanofiber incorporated N-TiO2 mat, LCNF/N-TiO2, was successfully developed using a simple solvent casting technique and utilized to address skin damages. This study evaluated the physicochemical characteristics of the LCNF mat using FT-IR, XRD, and SEM. The FT-IR and diffractogram signal confirmed the presence of N-TiO2 on the LCNF mat surface. The obtained microphotograph from the morphological analysis provided evidence of the formation of N-TiO2 particle aggregates on the LCNF mat surface. The enhancement of cell proliferation showed the biocompatibility effect of LCNF/N-TiO2. This result could be used as a baseline to develop the LCNF/N-TiO2 mat for advanced tissue engineering studies.
      PubDate: 2021-11-01
       
  • Hot–dog structured protective nanocoating for multifunctional cotton
           fabrics through spray–assisted layer–by–layer assembly

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      Abstract: Multifunctional cotton fabrics were prepared by low–cost and environmentally–friendly spray–assisted layer–by–layer assembly to simultaneously achieve excellent self–extinguishing ability, antistatic property and antimicrobial activity. Especially, a novel hot–dog structured protective coating was designed by was designed with the incorporation of polyaniline (PANI) nanofibers between graphene sheets, which could exhibit unique structural advantages and give full play to the compound synergetic effect. More clearly, 3–aminopropyl triethoxysilane, ammonium polyphosphate and PANI were selected for achieving phosphorus–silicon–nitrogen synergism in the assembled layer, while PANI nanofibers doped with various organic acids were intercalated between adjacent graphene sheets for constructing more stable and efficient protective space. The optimized coated fabric exhibited the excellent self–extinguishing ability for 5 composite layers including phytic acid doped nanofiber, and its limited oxygen index was increased significantly from 18.1% for neat cotton to 35.1%. Moreover, the peak heat release rate and the total heat release values were greatly declined by 78.3% and 49.0%, respectively. Furthermore, a low sheet resistance of 264.7 kΩ/sq for antistatic property, as well as remarkable growth inhibition of E. coli and S. aureus could be observed. In addition, the coated fabrics also had good washing durability. Therefore, such eco–friendly and facile large–scale fabrication approach has great potentials in application for multifunctional advanced textiles and could be employed to various kinds of other cellulose fibers. Graphic abstract
      PubDate: 2021-11-01
       
  • Structural properties of cellulose nanofibril foam depending on wet
           foaming conditions in Pickering stabilization

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      Abstract: Porous cellulose nanofibril (CNF) foam was prepared by stabilizing bubbles with CNF and a surfactant and then drying the stabilized wet foam in a convection oven. The consistency of carboxymethylated CNF (CMCNF) and the addition amount of the surfactant were controlled and the effects of these factors on the CNF wet foam and dry foam properties were investigated. An adequate amount of the surfactant (0.02–0.04 wt%) with CMCNF consistency higher than 0.5 wt% yielded wet foams with excellent stability. When the wet foam was dried at 60 °C in an oven, dry CNF foam with over 97% porosity was generated. The stable wet foams resulted in dry CNF foam with a sphere-like pore structure and low levels of shrinkage during drying. In contrast, unstable wet foams generated dry foam with severe shrinkage and large cavities. The pore size and the porosity of the dried foam were determined by the shape of bubbles in the wet foam and the degree of shrinkage during drying, which, in turn, affected the mechanical strength. In addition, the compressive strength of the oven-dried foam was 83% higher than that of the freeze-dried foam. Therefore, the preparation of a stable wet porous CMCNF foam by controlling the CMCNF consistency and the amount of surfactant was essential for obtaining a porous CMCNF foam with a uniform pore structure and good mechanical strength by oven drying. Graphic abstract
      PubDate: 2021-11-01
       
  • Hydrothermal treatments of aqueous cellulose nanocrystal suspensions:
           effects on structure and surface charge content

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      Abstract: Cellulose nanocrystals (CNCs) are ideal rheological modifiers for aqueous oil and gas extraction fluids. CNCs are typically produced with sulfuric acid and their aqueous suspensions have uniform and predictable properties under ambient conditions; however, drastic changes occur at elevated temperatures. Herein, the effects of high temperature treatments (ranging from 80 to 180 °C for 1 h to 7 days) on the properties (including uniformity, colloidal stability, and color) of sulfated, phosphated, and carboxylated CNC suspensions were studied. Additionally, cellulose molecular weight, and CNC surface charge content and crystallinity index were quantified before and after heating. CNCs underwent few morphological changes; their molecular weight and crystallinity index were largely unchanged under the conditions tested. Their surface charge content, however, was significantly decreased after heat treatment which resulted in loss of colloidal stability and aggregation of CNCs. The largest change in suspension properties was observed for sulfated CNCs whereas CNCs with a combination of sulfate and phosphate esters, or carboxylate groups, were less affected and maintained colloidal stability at higher temperatures. In fact, desulfation was found to occur rapidly at 80 °C, while many carboxylate groups persisted at temperatures up to 180 °C; calculated rate constants (based on second order kinetics) suggested that desulfation is 20 times faster than decarboxylation but with a similar activation energy. Overall, this study elucidates CNC suspension behavior after heat exposure and demonstrates routes to produce CNCs with improved high temperature performance. Graphic abstract
      PubDate: 2021-11-01
       
 
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