Reduced graphene sheets (RGSs) mediate electron transfer between sulfate-reducing bacteria (SRB) and solid electrodes, and promote the development of microbial fuel cells (MFC). We have investigated RSG-promoted elect...Reduced graphene sheets (RGSs) mediate electron transfer between sulfate-reducing bacteria (SRB) and solid electrodes, and promote the development of microbial fuel cells (MFC). We have investigated RSG-promoted electron transfer between SRB and a glassy carbon (GC) electrode. The RGSs were produced at high yield by a chemical sequence involving graphite oxidation, ultrasonic exfoliation of nanosheets, and N2H4 reduction. Cyclic voltammetric testing showed that the characteristic anodic peaks (around 0.3 V) might arise from the combination of bacterial membrane surface cytochrome c3 and the metabolic products of SRB. After 6 d, another anodic wave gradually increased to a maximum current peak and a third anodic signal became visible at around 0 V. The enhancements of two characteristic anodic peaks suggest that RSGs mediate electron-transfer kinetics between bacteria and the solid electrode. Manipulation of these recently-discovered electron-transport mechanisms will lead to significant advances in MFC engineering.展开更多
We present comparative life-cycle assessments of three fiber-reinforced sheet molding compounds (SMCs) using kenaf fiber, glass fiber and soy protein resin. Sheet molding compounds for automotive applications are ty...We present comparative life-cycle assessments of three fiber-reinforced sheet molding compounds (SMCs) using kenaf fiber, glass fiber and soy protein resin. Sheet molding compounds for automotive applications are typically made of unsaturated polyester and glass fibers. Replacing these with kenaf fiber or soy protein offers potential environmental benefits. A soy-based resin, maleated acrylated epoxidized soy oil (MAESO), was synthesized from refined soybean oil. Kenaf fiber and polyester resins were used to make SMC 1 composites, while SMC2 composites were made from kenaf fiber and a resin blend of 20% MASEO and 80% unsaturated polyester. Both exhibited good physical and mechanical properties, though neither was as strong as glass fiber reinforced polyester SMC. The functional unit was defined as mass to achieve equal stiffness and stability for the manufacture of interior parts for automobiles. The life-cycle assessments were done on SMCI, SMC2 and glass fiber reinforced SMC. The material and energy balances from producing one functional unit of three composites were collected from lab experiments and the literature. Key environmental measures were computed using SimaPro software. Kenaf fiber-reinforced SMC composites (SMC1 and SMC2) performed better than glass fiber-reinforced SMC in every environmental category. The global warming potentials of kenaf fiber-reinforced SMC (SMCI) and kenaf soy resin-based SMC (SMC2) were 45% and 58%, respectively, of glass fiber-reinforced SMC. Thus, we have demonstrated significant ecological benefit from replacing glass fiber reinforced SMC with soy-based resin and natural fiber.展开更多
High-efficiency photocatalysts are of great importance to satisfy the requirements of green chemistry nowadays.Here we reported a novel solar-driven photocatalyst fabricated by a facile surface modification method,wit...High-efficiency photocatalysts are of great importance to satisfy the requirements of green chemistry nowadays.Here we reported a novel solar-driven photocatalyst fabricated by a facile surface modification method,with the two-dimensional carboxylated zinc phthalocyanine-carboxylated C60-titanium dioxide(Zn Pc-C3-Ti O2)nanosheets,in which the surface modifications of Zn Pc and C60derivative were designed to extend the absorption range and promote charge separation,respectively.Benefiting from the unique structure and positive synergetic effect,the Zn Pc-C3-Ti O2 nanocomposite shows promising applications in selective reduction of nitroarenes for high-value-added aromatic amines under solar light.Especially,for the photocatalytic reduction of nitrobenzene to aniline,the Zn Pc-C3-Ti O2 nanocomposite possesses both high efficiency and selectivity(up to 99%).展开更多
基金Supported by the National Natural Science Foundation of China (No.41076047)the Shandong Provincial Natural Science Foundation of China (No. ZR2010DM004)the Chinese Academy of Sciences (No. KZCX2-YW-205-03)
文摘Reduced graphene sheets (RGSs) mediate electron transfer between sulfate-reducing bacteria (SRB) and solid electrodes, and promote the development of microbial fuel cells (MFC). We have investigated RSG-promoted electron transfer between SRB and a glassy carbon (GC) electrode. The RGSs were produced at high yield by a chemical sequence involving graphite oxidation, ultrasonic exfoliation of nanosheets, and N2H4 reduction. Cyclic voltammetric testing showed that the characteristic anodic peaks (around 0.3 V) might arise from the combination of bacterial membrane surface cytochrome c3 and the metabolic products of SRB. After 6 d, another anodic wave gradually increased to a maximum current peak and a third anodic signal became visible at around 0 V. The enhancements of two characteristic anodic peaks suggest that RSGs mediate electron-transfer kinetics between bacteria and the solid electrode. Manipulation of these recently-discovered electron-transport mechanisms will lead to significant advances in MFC engineering.
文摘We present comparative life-cycle assessments of three fiber-reinforced sheet molding compounds (SMCs) using kenaf fiber, glass fiber and soy protein resin. Sheet molding compounds for automotive applications are typically made of unsaturated polyester and glass fibers. Replacing these with kenaf fiber or soy protein offers potential environmental benefits. A soy-based resin, maleated acrylated epoxidized soy oil (MAESO), was synthesized from refined soybean oil. Kenaf fiber and polyester resins were used to make SMC 1 composites, while SMC2 composites were made from kenaf fiber and a resin blend of 20% MASEO and 80% unsaturated polyester. Both exhibited good physical and mechanical properties, though neither was as strong as glass fiber reinforced polyester SMC. The functional unit was defined as mass to achieve equal stiffness and stability for the manufacture of interior parts for automobiles. The life-cycle assessments were done on SMCI, SMC2 and glass fiber reinforced SMC. The material and energy balances from producing one functional unit of three composites were collected from lab experiments and the literature. Key environmental measures were computed using SimaPro software. Kenaf fiber-reinforced SMC composites (SMC1 and SMC2) performed better than glass fiber-reinforced SMC in every environmental category. The global warming potentials of kenaf fiber-reinforced SMC (SMCI) and kenaf soy resin-based SMC (SMC2) were 45% and 58%, respectively, of glass fiber-reinforced SMC. Thus, we have demonstrated significant ecological benefit from replacing glass fiber reinforced SMC with soy-based resin and natural fiber.
基金supported by Beijing Natural Science Foundation(2182094)the National Natural Science Foundation of China(51772300 and 51832008)the Youth Innovation Promotion Association of CAS(2018039)。
文摘High-efficiency photocatalysts are of great importance to satisfy the requirements of green chemistry nowadays.Here we reported a novel solar-driven photocatalyst fabricated by a facile surface modification method,with the two-dimensional carboxylated zinc phthalocyanine-carboxylated C60-titanium dioxide(Zn Pc-C3-Ti O2)nanosheets,in which the surface modifications of Zn Pc and C60derivative were designed to extend the absorption range and promote charge separation,respectively.Benefiting from the unique structure and positive synergetic effect,the Zn Pc-C3-Ti O2 nanocomposite shows promising applications in selective reduction of nitroarenes for high-value-added aromatic amines under solar light.Especially,for the photocatalytic reduction of nitrobenzene to aniline,the Zn Pc-C3-Ti O2 nanocomposite possesses both high efficiency and selectivity(up to 99%).