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51.
Xingye Gu Wei Lv Yangyang Hui Xiao Liu Minghui Wu Yan Yang Shixiong She 《无机化学与普通化学杂志》2019,645(8):663-668
The zinc(II) compound, [Zn3(HL)6]n ( 1 ) (H2L = 3‐hydroxypyridine‐2‐carboxylic acid) was synthesized by a solvothermal reaction of Zn(NO3)2 · 6H2O and 3‐hydroxypyridine‐2‐carboxylic acid as raw materials. The structure of complex 1 was determined by single‐crystal X‐ray diffraction analysis and further characterized by elemental analysis, Fourier transform infrared spectroscopy, thermogravimetric analysis, as well as powder X‐ray diffraction. X‐ray structure analysis demonstrates that the complex crystallizes in the monoclinic system, space group P21/n. There are three zinc ions in the asymmetric unit, which are either five‐coordinate or six‐coordinate. The asymmetric units are further bridged by the carboxylate of the organic ligands, featuring a 2D framework. The solid state diffuse‐reflectance UV/Vis spectra reveals that complex 1 has semiconducting nature with the energy bandgap (Eg) estimated to be 3.11 eV. The photocatalytic properties of complex 1 in degradation of organic dyes were further investigated. Results showed that the complex could degrade 54 % of the dye methylene blue solution within 120 min under UV irradiation light and reused for five times without the decline of the photocatalytic activity. 相似文献
52.
许兴业 《数学物理学报(A辑)》2000,20(Z1):675-683
该文讨论半线性椭圆型方程在环形区域上的Dirichlet(dirchlet-Neumann)边值问题. 相似文献
53.
Interaction of traditional Chinese Herb Rhizoma Chuanxiong and protein was studied by microdialysis coupled with high performance liquid chromatography. Compounds in Rhizoma Chuanxiong, such as ferulic acid, senkyunolide A and 3-butylphthalide, were identified by HPLC, HPLC-MS and UV-vis. Microdialysis recoveries and binding degrees of compounds in Rhizoma Chuanxiong with human serum albumin (HSA) and other human plasma protein were determined: recoveries of microdialysis sampling ranged from 36.7 to 98.4% with R.S.D. below 3.1%; while binding to HSA ranged from 0 to 91.5% (0.3 mM HSA) and from 0 to 93.5% (0.6 mM HSA), respectively. Compared with HSA, most of compounds bound to human blood serum more extensively and the results showed that binding of these compounds in Rhizoma Chuanxiong was influenced by pH. Two compounds were found to bind to HSA and human blood serum, their binding degrees were consistent with ferulic acid and 3-butylphthalide, the active compounds in Rhizoma Chuangxiong. 相似文献
54.
JIANGLISHANG LIUZUHAN YIFAHUAI YUEXINGYE 《高校应用数学学报(英文版)》1995,10(1):1-10
This paper deals with the relationship between a certain three-dimensional elliptic problem and a two-dimensional parabolic problem, which arises from numerical calculation in the process of the continuous casting of steel. 相似文献
55.
Xingye Mu Hanxiao Yu Henian Peng Wenrui Xiong Ting Wu Prof. Dr. Wenjun Tang 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2020,132(21):8220-8224
A powerful palladium-catalyzed dearomative cyclization was developed that provides facile access to eight types of bridged tetracyclic skeletons bearing various ring sizes and heterocycles. With this method, several skeletons or analogues of natural products, including tubingensin B and dracaenones, were synthesized. Asymmetric dearomative cyclization enables the construction of various enantiomerically enriched bridged polycyclic systems with up to 99 % ee by employing a chiral palladium catalyst. 相似文献
56.
A stationary phase for high performance affinity chromatography with immobilization of DNA onto silica gel was prepared and characterized. The effect of the ionic strength, concentration of Mg2+, EDTA and CH3CN in the mobile phase on the retention of alkaloids were investigated. With this stationary phase, biological fingerprinting analysis of traditional Chinese medicines (TCMs) Coptis chinensis Franch and Rheum palmatum L. was performed with both one-dimensional (1-D) and two-dimensional (2-D) chromatography. The 1-D chromatography was performed with isocratic and gradient elution and 2-D chromatography was developed with immobilized DNA column combined with silica monolithic ODS column. It was found that 7 compounds in Coptis chinensis Franch including berberine, palmatine and jatrorrhizine, 14 compounds in Rheum palmatum L. including aloe-emodin, rhein, emodin, chrysophannol-8-O-glucophranoside and physionl-8-O-glucophranoside were active in binding to the immobilized DNA. 相似文献
57.
The reaction mechanism for the reduction of CO(2) gas activated by (tBuArN)(3)M≡N was studied by the means of density functional theory (DFT) calculations. The calculations indicated that this reaction has a two step reaction mechanism. From our calculations, we found that (tBuArN)(3)Ta≡N held the best activity among the three (tBuArN)(3)M≡N complexes studied. Our results also indicated that the reaction of (tBuArN)(3)M≡N with CO(2) occurred under orbital control involving the HOMO-3 orbital of (tBuArN)(3)M≡N, which could give higher overlapping with the LUMO of the CO(2) molecule. The substitutions on the amino donor ligands studied here took larger effect on the HOMO structure of the (tBuArN)(3)M≡N molecules. The electronic structure of the (tBuArN)(3)M≡N complexes also showed their ability for activating CO(2) molecules, in the order of M = V < Nb < Ta. 相似文献
58.
Ahighly persistent benzoanthracenyl radical(BAR1) protected by five substituents at strategic positions is synthesized. BAR1 exhibited half-life time of 108 h in air-saturated solution, which allowed for detailed characterization in the solution. The combined experimental and theoretical study reveals the properties associated with its asymmetric structure and spin distribution. One-electron oxidation of BAR1 afforded stable cationic species BAR1+, whose structure is unambiguously determined by the NMR spectroscopy. 相似文献
59.
关于球内奇异非线性椭圆边值问题的正解 总被引:2,自引:0,他引:2
本文建立了一类球内奇异的椭圆边值问题正解的存在性定理,发展了Usami,H.^[2]于1989年所得的部分结果。 相似文献