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101.
Zhi Qiang Shi Ya Qing Feng Bing Zhao Wen Xiang Wang 《中国化学快报》2007,18(12):1493-1495
A novel series of N-alkylphthalimidylaminocarbonylmethoxylcalix[4]arenes with the reaction between 4-(N-bromoacetyla- mino)-phthalimide derivatives and calix[4]arene has been synthesized and structurally characterized by IR,~1HNMR and MS.From their analysis data,it was found that compounds 7a-7d adopted a cone conformation. 相似文献
102.
103.
Qiang ZHAO Qian Kun ZHUANG 《中国化学快报》2005,16(9):1237-1240
With 1-Pymnebutyric acid (PBA) and multiwalled carbon nanotubes (MWNTs), glassy carbon electrode modified was successfully prepared. In phosphate buffer solution (pH 7,0), the direct electrochemistry of cytochrome C (Cyt C) was realized. In the cyclic voltammetry experiment two pairs of redox peaks ofCyt C were observed at 0.018 V and -0.314 V (vs. SCE), respectively. The redox reaction at 0.018 V was diffusion controlled, while the redox reaction at -0.314 V was adsorption controlled. 相似文献
104.
A New Reaction-controlled Phase-transfer Catalyst System 总被引:1,自引:0,他引:1
MingQiangLI XiGaoJIAN GuiMeiWANG YanYU 《中国化学快报》2004,15(3):350-352
A new reaction-controlled phase-transfer catalyst system was designed and synthesized.In this system, heteropolytungstate [C7H7N(CH3)3]9PW9O34 was used for catalytic epoxidation of cyclohexene with H2O2 as the oxidant. The conversion of H2O2 was 100% and the yield of cyclohexene oxide was 87.1% based on cyclohexene. Infrared spectra showed that both fresh catalyst and the recovered catalyst do have completely same absorption peak, indicating the structure of catalyst is very stability and can be recycled. 相似文献
105.
Qi SUN Qiang XIAO Yong JU* Yu Fen ZHAO The Key Laboratory of Bioorganic Phosphorus Chemistry of Education Ministry Department of Chemistry School of Life Sciences Engineering Tsinghua University Beijing 《中国化学快报》2003,14(7):685-688
It is known that saccharides linked to proteins via a phosphoester hinge can function as immunological determinants. Under regular physiological conditions, it has been suggested that the role of phosphonate group is to direct the protease towards basic substrates1. Phosphoramidon a, which was isolated from a culture filtrate, is a potent inhibitor of the thermolysin, a metallo-endopeptidase. It is a glycosylated dipeptide, which has a L-rhamnose attached to the N-terminal of Leu-Trp dipep… 相似文献
106.
Chromatographic Features and Molecular Recognition Mechanism of a Strychnine Monolithic Molecularly Imprinted Polymer 总被引:1,自引:0,他引:1
A monolithic molecularly imprinted polymer (mMIP) with specific recognition ability for strychnine was prepared by in-situ polymerization, using methacrylic acid (MAA) as a functional monomer, ethylene glycol dimethacrylate (EDMA) as a cross-linking agent, toluene and dodecanol as porogenic solvents and 2, 2’-azobisisobutyronitrile (AIBN) as a initiator. Scanning electron microscopy and mercury intrusion porosimetry were used to identify the structural features of the mMIP. The results show that there were three kinds of pore structures. The large through-pore structure allows mobile phase to flow through a column of mMIP with a low back pressure and the other pores lead to the molecular recognition. Some chromatographic conditions such as the pH and the composition of the mobile phase were characterized. Strychnine was separated from compounds such as indole, quinine and brucine. The possible recognition mechanisms were ionic and hydrogen bonding interactions between the strychnine molecule and the mMIP. 相似文献
107.
108.
Polycrystal Li2B4O7 (LBO) doped with Cu and In was prepared and then sintered at different temperatures. X-ray diffraction (XRD) was applied
to get the parameters of the LBO structure, thermoluminescence (TL) and optically stimulated luminescence (OSL) were measured,
and a second-order exponential decay model was fitted to the OSL decay curves. The results indicate that the original number
of OSL traps that have captured electroncs is linearly related with the sum of TL decay during the OSL process. Mean decay
constant of OSL is related to the sintered temperature. The possible reason is that the sintered temperature affects the crystal
sizes of the polycrystal, and consequently affects the stimulating lights’s intensity and the photoionization cross-section
of the electrons, which have been captured by the traps.
__________
Translated from Acta Scientiarum Naturalium Universitatis Sunyatseni, 2005, 44(4) (in Chinese) 相似文献
109.
中药一枝黄花、黄连、天麻、蛇床子中8种微量元素的测定 总被引:13,自引:2,他引:13
采用原子吸收光谱仪对一枝黄花、黄连、天麻、蛇床子中Fe、Ca、Mg、Mn、Cr、Cu、Zn、Pb八种无机元素的含量进行了测定,为进一步研究其药理和用途提供基础。 相似文献
110.