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  • Self-Supported Nanoporous Gold with Gradient Tin Oxide for Sustainable and Efficient Hydrogen Evolution in Neutral Media
  • Abstract Hydrogen evolution reaction (HER) in neutral medium suffers from slow kinetics as compared to that in alkaline or acidic conditions, owing to larger Ohmic loss and low proton concentration. Here we report that a self-supported nanoporous Au-SnOx (NP Au-SnOx) catalyst with gradient tin oxide surface could significantly enhance HER activity in neutral buffer solution (0.2 M PBS). The NP Au-SnOx catalyst exhibits a low onset overpotential of 38 mV and a small Tafel slope of 79 mV dec−1 . The current density of 10 mA cm−2 is manifested at an overpotential as low as 148 mV, representing the comparable performance…
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  • Experimental Research on Structural Behaviors of Glulam I-Beam with a Special-Shaped Section
  • Abstract In order to enhance the bearing capacity of structural components, save materials, and reduce cost, a glued laminated timber (glulam) I-beam that is theoretically suitable for engineering application was proposed. In this study, 18 glulam specimens were fabricated using larch dimension lumber and resorcinol– formaldehyde resin. Four-point bending tests were carried out to compare the ultimate bearing capacity, strain, and deflection of various specimens. The results showed that: (1) The typical failure mode at bending is the web shear failure parallel to grain. Before the failure, cracks and sounds appear at the beam web, which represent the sudden brittle failure.…
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  • Isolation of Thermally Stable Cellulose Nanocrystals from Spent Coffee Grounds via Phosphoric Acid Hydrolysis
  • Abstract As the world's population exponentially grows, so does the need for the production of food, with cereal production growing annually from an estimated 1.0 billion to 2.5 billion tons within the last few decades. This rapid growth in food production results in an ever increasing amount of agricultural wastes, of which already occupies nearly 50% of the total landfill area. For example, is the billions of dry tons of cellulose-containing spent coffee grounds disposed in landfills annually. This paper seeks to provide a method for isolating cellulose nanocrystals (CNCs) from spent coffee grounds, in order to recycle and utilize the…
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  • Two Routes to Produce Chitosan from Agaricus bisporus
  • Abstract Two methods were used to produce chitosan by deacetylation of chitin which was extracted from Agaricus bisporus stipes. The first one gives chitosan 1 with low yield of 2.5%, degree of acetylation (DA) of 4%, molecular weight (MW) of 2.973 × 105 (g/mol). The second route produces chitosan 2 with higher yield of 41%, degree of acetylation (DA) of 17.23%, molecular weight (MW) of 2.939 × 105 (g/mol). Both chitosans were characterized by XRD, FTIR, 1 H-NMR spectroscopy nuclear magnetic resonance of proton. The molecular weight (MW) was determined by size exclusion chromatography (SEC). Thermal analysis shows that both chitosans…
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  • Poly (vinyl alcohol)/Graphene Nanocomposite Hydrogel Scaffolds for Control of Cell Adhesion
  • Abstract Poly (vinyl alcohol) (PVA)/reduced graphene oxide (rGO) nanocomposites is prepared by the immersion of PVA/graphene oxide (GO) nanocomposites in the reducing agent aqueous solution. The PVA/graphene nanocomposites can be used as scaffold after treatment by chemical crosslinking agents. The surface hydrophilicity of the nanocomposite scaffolds decreased with the addition of GO or rGO by measuring the contact angles of scaffolds. The electrical conductivity of PVA/rGO nanocomposite scaffold increased with rGO content increased. The highest conductivity of PVA/rGO nanocomposite scaffolds with 10 wt% rGO could reach to 12.16 × 10−3 S/m. The NIH-3T3 fibroblasts attach and grow well on the surface…
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  • Mannonic Acid and Bio-Ethanol Production from Konjac Using a Two-Step Bioprocess with Candida Shehatae and Gluconobacter Oxydans
  • Abstract Amorphophallus konjac is rich in glucomannan, which can be hydrolyzed into glucose and mannose, thereby acting as an economic raw material for the acquisition of glucose and mannose. The total sugar yield was 91.2% when konjac powder was treated with 0.75% hydrochloric acid at 121°C for 1 h. Thus, dilute acid hydrolysates of konjac powder were used as a carbon source for obtaining value-added products. Here we showed that the microbial production of ethanol and mannonic acid was obtained by employing Candida shehatae (C. shehatae) and Gluconobacter oxydans (G. oxydans). Through a step-by-step bioprocess, glucose is the first selectively converted…
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  • Green Synthesis of Silver Nanoparticles from Abronia villosa as an Alternative to Control of Pathogenic Microorganisms
  • Abstract The aim of this study was to evaluate the antibacterial and antifungal activities of eco-friendly synthesized silver nanoparticles. The silver nanoparticles were synthesized by biological method using aqueous extract of Abronia villosa. Synthesis of silver nanoparticles was confirmed by color change and characterized using UV-visible spectroscopy, scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDX), dynamic light scattering (DLS), and zeta potential analysis. The SEM analysis revealed the presence of spherical silver nanoparticles of the size range 21 to 33 nm. Synthesized silver nanoparticles were used to evaluate their antibacterial effects at different concentrations (25, 50, 75 and 100 µg/ml)…
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  • Synthesis and Characterization of UV Oligomer based on Cardanol
  • Abstract In the present research, cardanol based di-acrylic UV oligomer was synthesized by thiol-ene coupling followed by ring opening reaction with glycidyl methacrylate. The intermediate as well as final diacrylate materials were analyzed by chemical as well as spectroscopic analysis. Further, ultraviolet (UV) radiation curable formulations were prepared by replacing commercial epoxy acrylate with synthesized UV oligomer in 10-50 wt% and applied on wood panels. The coated films were then evaluated for their optical, mechanical, chemical and thermal properties. Studies showed that up to 30 wt% amount of UV oligomer the coatings exhibited at par mechanical and chemical properties. The stain…
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  • The Effects of DOPO-g-ITA Modified Microcrystalline Cellulose on the Properites of Composite Phenolic Foams
  • Abstract In order to improve the comprehensive performance of phenolic foam, 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) was grafted with itaconic acid (ITA) (DOPO-g-ITA) to modify microcrystalline cellulose (MCC). DOPO-g-ITA modified MCC (DIMMCC) was used to prepare composite phenolic foam (DCPF). The structures of DIMMCC were verified by Fourier transform infrared spectroscopy (FT-IR). The microstructure and crystalline property were characterized by scanning electron microscope (SEM) and X-ray diffraction (XRD) respectively. Compared with MCC, the crystallinity of DIMMCC was dramatically decreased, but the diffraction peak positions were unchanged. Thermal stability was decreased, and Ti decreased by 45.0°C. The residual carbon (600°C) was increased by 22.34%.…
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Displaying 11-20 on page 2 of 308. Per Page