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An optimal hydrophobic ionic liquid was discovered as a solvent for highly enantioselective glyoxylate-ene reactions catalyzed by a chiral bis(oxazoline)–copper complex. The reactivity and stereoselectivity were highly dependent upon the property of the ionic liquids; reactions between olefins and ethyl glyoxylate in [Bmim]SbF6 at ambient temperature provided remarkably enhanced reactivity and stereoselectivity, which greatly exceed those of the corresponding reactions in dichloromethane. Furthermore, the metal–ligand complex was readily recycled up to eight times while exhibiting no significant decrease in reaction efficiency. 相似文献
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Won-Kun Park Gursong Yoo Myounghoon Moon Chul Woong Kim Yoon-E Choi Ji-Won Yang 《Applied biochemistry and biotechnology》2013,171(5):1128-1142
Cultivation is the most expensive step in the production of biodiesel from microalgae, and substantial research has been devoted to developing more cost-effective cultivation methods. Plant hormones (phytohormones) are chemical messengers that regulate various aspects of growth and development and are typically active at very low concentrations. In this study, we investigated the effect of different phytohormones on microalgal growth and biodiesel production in Chlamydomonas reinhardtii and their potential to lower the overall cost of commercial biofuel production. The results indicated that all five of the tested phytohormones (indole-3-acetic acid, gibberellic acid, kinetin, 1-triacontanol, and abscisic acid) promoted microalgal growth. In particular, hormone treatment increased biomass production by 54 to 69 % relative to the control growth medium (Tris–acetate–phosphate, TAP). Phytohormone treatments also affected microalgal cell morphology but had no effect on the yields of fatty acid methyl esters (FAMEs) as a percent of biomass. We also tested the effect of these phytohormones on microalgal growth in nitrogen-limited media by supplementation in the early stationary phase. Maximum cell densities after addition of phytohormones were higher than in TAP medium, even when the nitrogen source was reduced to 40 % of that in TAP medium. Taken together, our results indicate that phytohormones significantly increased microalgal growth, particularly in nitrogen-limited media, and have potential for use in the development of efficient microalgal cultivation for biofuel production. 相似文献
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E. A. Il’ina A. V. Aleksandrov A. A. Raskovalov N. N. Batalov 《Russian Journal of Applied Chemistry》2013,86(8):1225-1229
Results of a study of how the density and electrical conductivity of a Li7La3Zr2O12 ceramic depends on the sintering temperature were used to determine the optimal conditions for formation of the system under study as a solid electrolyte with a conductivity of 3.7 × 10?2 S cm?1 at 185°C for electrochemical devices. 相似文献
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Biomimetic pH/redox dual stimuli‐responsive zwitterionic polymer block poly(L‐histidine) micelles for intracellular delivery of doxorubicin into tumor cells 下载免费PDF全文
Johnson V. John Saji Uthaman Rimesh Augustine Kamali Manickavasagam Lekshmi In‐Kyu Park Il Kim 《Journal of polymer science. Part A, Polymer chemistry》2017,55(12):2061-2070
A series of pH/redox dual stimuli‐responsive poly(2‐methacryloyloxyethyl phosphorylcholine)25‐block‐poly(l ‐histidine)n (p[MPC])25‐b‐p[His]n, n = 20, 35, 50, and 75) copolymers consisting of a pH‐responsive p(His)n block and a biocompatible phospholipid analog p(MPC) block connected by a redox‐responsive disulfide linker have been synthesized. The block copolymers are self‐assembled into uniform micelles (~100 nm) in which doxorubicin (Dox) is efficiently encapsulated. The in vitro release profile shows an enhanced release of Dox at low pH (5.0) in 10 mM glutathione (GSH). The in vitro cell viability assays performed using various cell lines show that the blank hybrid micelles have no acute or intrinsic toxicity. A pH‐dependent cytotoxicity is observed with the Dox‐loaded micelles, especially at pH 5.0. Moreover, confocal microscopy images and flow cytometry results show the pH‐dependent cellular uptake of Dox‐loaded micelles. Therefore, the Dox‐loaded micelles can be considered a good candidate for cancer therapy. © 2017 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2017 , 55, 2061–2070 相似文献
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We have analyzed the effect of constant electric and magnetic fields on the micro- and substructure characteristics of the combustion products of aluminum nanopowder in air. It has been found that the combustion of aluminum nanopowder in a magnetic field leads to the formation of single crystals of the hexagonal habitus, while the combustion in an electric field results in the formation of faceted crystallites with layered morphology. The fields noticeably affect the crystal lattice parameters of aluminum oxide and nitride (reduce the coherent scattering regions in aluminum nitride and increase such regions in aluminum γ-oxide). At the same time, the displacement of atoms relative to the equilibrium position becomes noticeably smaller for all crystal phases under the action of the fields (except for aluminum nitride in a magnetic field). These results have been explained by the orienting and stabilizing actions of the fields on the combustion products of aluminum nanopowder in air. 相似文献