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61.
Xiu‐Li Wang Ke‐Ke Yang Yu‐Zhong Wang Zhi‐Xuan Zhou Yong‐Dong Jin 《Journal of polymer science. Part A, Polymer chemistry》2004,42(14):3417-3422
A new biodegradable starch graft copolymer, starch‐g‐poly(1,4‐dioxan‐2‐one), was synthesized through the ring‐opening graft polymerization of 1,4‐dioxan‐2‐one onto a starch backbone. The grafting reactions were conducted with various 1,4‐dioxan‐2‐one/starch feed ratios to obtain starch‐g‐poly(1,4‐dioxan‐2‐one) copolymers with various poly(1,4‐dioxan‐2‐one) graft structures. The microstructure of starch‐g‐poly(1,4‐dioxan‐2‐one) was characterized in detail with one‐ and two‐dimensional NMR spectroscopy. The effect of the feed composition on the resulting microstructure of starch‐g‐poly(1,4‐dioxan‐2‐one) was investigated. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 3417–3422, 2004 相似文献
62.
ZHANG Jing wen * ZHAO Jian zhang ZHANG Xiao long JIANG Yu lin MA Xiu li SUN Yun xiu JIANG Wen pu LI Yao xian XU Zhi luo 《高等学校化学研究》1998,(2)
ChemoselectiveCatalyticHydrogenationofα,β┐UnsaturatedKetonesandα,β┐UnsaturatedCarboxylicEstersZHANGJing-wen*,ZHAOJian-zhang,Z... 相似文献
63.
Enantioselective catalytic trimethylsilylcyanations of aldehydes with 48% to 92% e.e. have been studied using the novel Ti-chiral Schiff base complexes. We have found that the catalyst led to high enantoselectivity when the molar ratio of the Schiff base 1 to Ti(O-i-Pr)4 was 2:1. 相似文献
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Juan Hong Liang-Fu Tang Zhi Yang Yu-Ping Zhai Mujia Nan 《Transition Metal Chemistry》2005,30(4):439-444
A series of [M(CO)5I]− and [M2(CO)10I]− anion complexes have been synthesized by the photochemical reaction of PhCH2N(CH3)3I or FcCH2N(CH3)3I (Fc=ferrocenyl) with M(CO)6 (M = Cr, Mo or W), and characterized by elemental analyses, i.r., 1H-n.m.r. and 13C-n.m.r. spectra in the case of the molybdenum and tungsten complexes. These complexes exhibit considerably different electrochemical behavior, when investigated by cyclic voltammetry. The crystal structures of [PhCH2N(CH3)3][Cr(CO)5I] and [FcCH2N(CH3)3][W2(CO)10I] have been determined by X-ray diffraction, indicating that only weak contacts maybe exist between anions and cations by the I...H bond in the former, and there are no direct interactions between anions and cations in the latter. 相似文献
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Fang Fang Zhong Yu Chen Zhi Nan Mei Guang Zhong Yang 《中国化学快报》2007,18(7):849-851
Two novel xanthones, 1,6-dihydroxy-4,5-dimethoxyxanthone (1) and 1,5,6-trihydroxy-7,8-di(3-methyl-2-butenyl)-60,60- dimethylpyrano(20,30:3,4)xanthone (2) were isolated from the bark of Garcinia xanthochymus by normal phase and reverse phase silica gel column chromatography. Their structures were elucidated by spectroscopic methods, especially 2D-NMR techniques. 相似文献
70.
A new fluorescent compound based on calix[4] arene skeleton was synthesized.Its complexation ability with transition metal ions,such as Fe^3 ,Co^2 ,Ni^2 ,Cu^2 ,Zn^2 and Ag^ ,Was investigated by UV-vis and fluorescent spectra. 相似文献