In this paper, the immobilized pellets were prepared by embedding Pichia pastoris (P. pastoris) with sodium alginate and used for the recovery of palladium ions in solution. The catalytic activity of immobilized Pd/P....In this paper, the immobilized pellets were prepared by embedding Pichia pastoris (P. pastoris) with sodium alginate and used for the recovery of palladium ions in solution. The catalytic activity of immobilized Pd/P. pastoris for 4-nitrophenol (4-NP) was studied. The results showed that the recovery rate of Pd ions could be significantly increased by immobilized cells. The immobilized Pd/P. pastoris pellets showed good catalytic activity for the reduction of 4-NP, and the catalyst remained good catalytic activity even after multiple reuses.展开更多
Two polyurethanes of different molecular weights were prepared by the copolymerization of phenyl diisocyanate and diisopropyl tartrate. The polyurethanes having terminal isocyanate groups were reacted with 3-aminoprop...Two polyurethanes of different molecular weights were prepared by the copolymerization of phenyl diisocyanate and diisopropyl tartrate. The polyurethanes having terminal isocyanate groups were reacted with 3-aminopropyl silica gel to afford two chiral stationary phases. The M^- n of the two polyurethanes were 4057 g/mol and 6442 g/mol. The polyurethanes and the corresponding chiral stationary phases were characterized by FT-IR,^1 H NMR and elemental analysis. The loading capacities of the polyurethanes on silica gel were 0.68 mmol units/g and 0.61 mmol units/g, respectively. The separation performance and the influence of additives, triethylamine and trichloroacetic acid, on the separation of chiral compounds were investigated by HPLC. The chiral stationary phase prepared from polyurethane with M^- n of 4057 g/mol demonstrated better enantioseparation capability than that with M^- n of 6442 g/mol. Additionally, it was found that the addition of triethylamine and trichloroacetic acid in the mobile phases significantly improved the enantioseparation for these two chiral stationary phases.展开更多
文摘In this paper, the immobilized pellets were prepared by embedding Pichia pastoris (P. pastoris) with sodium alginate and used for the recovery of palladium ions in solution. The catalytic activity of immobilized Pd/P. pastoris for 4-nitrophenol (4-NP) was studied. The results showed that the recovery rate of Pd ions could be significantly increased by immobilized cells. The immobilized Pd/P. pastoris pellets showed good catalytic activity for the reduction of 4-NP, and the catalyst remained good catalytic activity even after multiple reuses.
基金This work was supported by the National Natural Science Foundation of China (No. 20371037)the Natural Science Foundation of Hubei Province, China (No. 2002AB066).
文摘Two polyurethanes of different molecular weights were prepared by the copolymerization of phenyl diisocyanate and diisopropyl tartrate. The polyurethanes having terminal isocyanate groups were reacted with 3-aminopropyl silica gel to afford two chiral stationary phases. The M^- n of the two polyurethanes were 4057 g/mol and 6442 g/mol. The polyurethanes and the corresponding chiral stationary phases were characterized by FT-IR,^1 H NMR and elemental analysis. The loading capacities of the polyurethanes on silica gel were 0.68 mmol units/g and 0.61 mmol units/g, respectively. The separation performance and the influence of additives, triethylamine and trichloroacetic acid, on the separation of chiral compounds were investigated by HPLC. The chiral stationary phase prepared from polyurethane with M^- n of 4057 g/mol demonstrated better enantioseparation capability than that with M^- n of 6442 g/mol. Additionally, it was found that the addition of triethylamine and trichloroacetic acid in the mobile phases significantly improved the enantioseparation for these two chiral stationary phases.
