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Abstract: Single crystalline flower-like Bi2S3 nanostructures were successfully synthesized via a simple, facile and green hydrothermal method, with the assistance of D-penicillamine. The products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM), and found their morphologies mainly depend on the ratios of Bi3+ to D-penicillamine, as well as the reaction temperature and time. And the possible growth mechanism has been discussed in some detail. In addition, the as-prepared Bi2S3 nanoflowers show good hydrogen storage ability. This strategy can be potentially expanded to prepare other metal chalcogenides materials. [Copyright &y& Elsevier]

Abstract: Enzymatic modification of starch was conducted by lipase-coupling esterification with octenyl succinic anhydride (OSA). Parameters affecting the esterification were systematically studied. Products were characterized by Fourier transform infrared (FT-IR) spectroscopy, scanning electron microscopy (SEM), X-ray diffraction, differential scanning calorimetry (DSC) and viscosity analysis (VA). Optimum condition for lipase-coupling OSA starch preparation was as follows: starch pretreatment at 65°C for 15min, starch concentration 35%, amount of lipase and OSA, 0.6% and 3%, reaction pH, temperature and time, 8.0, 40°C and 30min respectively, which resulted in 0.0195 of the degree of substitution and 84.05±2.07% of the reaction efficiency. FT-IR spectroscopy confirmed the formation of OSA starch. SEM and X-ray diffraction showed apparent surface change, but no crystalline change. DSC and VA results indicated the synthesized OSA starch gelatinized rapidly with high viscosity. Attractively, reaction time drastically reduced to 30min, showing vast potential for scale production of OSA starch. [Copyright &y& Elsevier]