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51.
D-氨基葡萄糖Schiff碱及其金属配合物的抗菌活性 总被引:16,自引:0,他引:16
The effects of D-glucosamine schiff base and its metal complexes on the growth of Aerobacter aerogenes were investigated by the microcalorimetry. Among the substances tested. Zn-SG was shown to be the most bacteriostasic, followed by Zn-o-VG and SG (with the Ic50 of 242, 287 and 320 μg•mL-1, respectively). Cu(Ⅱ)-SG showed less inhibitory effect on Aerobacter aerogenes over the concentration rang of 50~300μg•mL-1. 相似文献
52.
Ming‐Yi Chen Jian‐Xun Wang Kung‐Tung Chen Bi‐Zhou Wen Wei‐Chieh Lin Chiing‐Chang Chen 《中国化学会会志》2012,59(2):170-175
Calcium carbide residue (CCR) was investigated in transesterification reaction of triglycerides to determine its viability as a solid catalyst for biodiesel synthesis. Literature survey showed that CCR has never been studied as a solid catalyst in the transesterification of triglyceride. The scope of the study includes the effects of CCR calcination temperature, calcination time, the alcohol/oil molar ratio, the catalyst amount (wt % of oil) and the reaction time. The relationship between chemical composition and catalytic activity of waste cement was also investigated. These CCR catalysts, thermally activated at 600 °C, can give rise to fatty acid methyl esters (FAME) purity higher than 99.5%, after 3 h of reaction, when oil/methanol molar ratio of 1/12 and 1 wt % of the catalyst were employed. Application of CCR as catalyst for biodiesel production in this study may not only provide a cost‐effective and environment friendly way of recycling CCR waste but also reduce hopefully the cost of biodiesel production. 相似文献
53.
Qi Teng Wenxiu Mao Dong Chen Zhen Wang Chen‐Ho Tung Zhenghu Xu 《Angewandte Chemie (International ed. in English)》2020,59(6):2220-2224
A rhodium(I)‐BINAP‐catalyzed highly enantioselective [2+2+2] cycloaddition of enynes with alkynes has been developed. Diverse fused tricyclic hydronaphthofuran scaffolds with three consecutive stereogenic centers were constructed in one step from easily available materials with excellent chemo‐, regio‐, diastereo‐, and enantioselectivity. Notable features of these reactions include 100 % atom economy, very broad scope, and mild reaction conditions. 相似文献
54.
55.
High‐Nuclear Organometallic Copper(I)–Alkynide Clusters: Thermochromic Near‐Infrared Luminescence and Solution Stability
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Hong‐Yan Zhuo Dr. Hai‐Feng Su Zhao‐Zhen Cao Wei Liu Prof. Shu‐Ao Wang Lei Feng Dr. Gui‐Lin Zhuang Dr. Shui‐Chao Lin Prof. Mohamedally Kurmoo Prof. Chen‐Ho Tung Dr. Di Sun Prof. Lan‐Sun Zheng 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(49):17619-17626
Cu(CF3COO)2 reacts with tert‐butylacetylene (tBuC≡CH) in methanol in the presence of metallic copper powder to give two air‐stable clusters, [CuI15(tBuC≡C)10(CF3COO)5]?tBuC≡CH ( 1 ) and [CuI16(tBuC≡C)12(CF3COO)4(CH3OH)2] ( 2 ). The assembly process involves in situ comproportionation reaction between Cu2+ and Cu0 and the formation of two different clusters is controlled by reactants concentration. The clusters consist of Cu15 and Cu16 cores co‐stabilized by strong by σ‐ and π‐bonded tert‐butylethynide and CF3COO? (together with methanol molecule in 2 ). Their stabilities in solution were confirmed using electrospray ionization mass spectrometry in which the cluster core remains intact for 1 in chloroform and acetone, and for 2 in acetonitrile. Strong thermochromic luminescence in the near infrared (NIR) region was observed in the solid‐state. Of particular interest, the emission maximum of 1 is red‐shifted from 710 nm at 298 K to 793 nm at 93 K, along with a 17‐fold fluorescence enhancement. In contrast, 2 exhibits red shift from 298 to 123 K followed by blue shift from 123 to 93 K. The emission wavelength was correlated with the structural parameters using variable‐temperature X‐ray single‐crystal analyses. The rich cuprophilic interaction plays a significant role in the formation of 3LMCT (tBuC≡C→Cux) excited state mixed with cluster‐centered (3CC) characters, which can be considerably influenced by temperature, leading to thermochromic luminescence. The present work provides 1) a new synthetic protocol for the high‐nuclear CuI–alkynyl clusters; 2) a comprehensive insight into the mechanism of thermochromic luminescence; 3) unusual emissive materials with the characters of NIR and thermochromic luminescence simultaneously. 相似文献
56.
N. T. Tung T. X. Hoai V. D. Lam J. W. Park V. T. Thuy Y. P. Lee 《The European Physical Journal B - Condensed Matter and Complex Systems》2010,74(1):47-51
Matching the impedance of a medium to free space, which is usually not available in natural materials, is an important advance
in metamaterials. In this paper, we present a simple mechanism for a perfect impedance-matched left-handed metamaterials,
that reveals a nearly zero reflection over operating frequency. This finding is based on the independent manipulation of the
electric response without any effect on the magnetic one. 相似文献
57.
Regular conjugated terpolymers comprising two different acceptors and bithiophene donor in repeating group: Effect of strong and weak acceptors on semiconducting properties
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Duc Nghia Nguyen Trinh Tung Ngo Dae Hee Lee Min Ju Cho Dong Hoon Choi 《Journal of polymer science. Part A, Polymer chemistry》2016,54(10):1339-1347
Diketopyrrolopyrrole (DPP)‐based terpolymers—P(DPP‐TPyT) and P(DPP‐T3MTT)—bearing bithiophene donating groups and weak accepting units such as pyridine (Py) or methyl thiophene‐3‐carboxylate (3MT), in the polymer backbone, were successfully synthesized. Although the two polymers had similar physical and electrochemical properties, grazing incidence X‐ray diffraction patterns of P(DPP‐TPyT) and P(DPP‐T3MTT) showed mixed and edge‐on orientations, respectively, in thermally annealed films. Accordingly, the P(DPP‐T3MTT) showed twice the hole mobility of P(DPP‐TPyT) in a thin‐film transistor, and a blended film of P(DPP‐T3MTT) and [6,6]‐phenyl‐C71‐butyric acid methyl ester (PC71BM) showed better power conversion efficiency in a polymer solar cell. © 2015 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2016 , 54, 1339‐1347 相似文献
58.
We expand the picture of plasmon hybridization in metamagnetic structure via numerically studying the electromagnetic coupling in the metallic cut-wire-pair super cells. It is shown that a triple negative permeability band can be achieved by systematically controlling the plasmon hybridization in such the structure. The corresponding transmission properties as well as the electromagnetic responses of the plasmon-hybridized structures were presented by using the finite integration technique simulations. Our results would reveal a promising design to obtain the multiple negative refractions based on the combination of hybridized cut-wire-pairs and continuous wires. 相似文献
59.
Photoluminescence with high quantum yield and long lifetime from a triplet metal-to-ligand charge transfer (MLCT) excited state in fluid solution at room temperature has been observed for a series of platinum(II) 4'-p-tolyl-terpyridyl acetylide complexes. 相似文献
60.
[reaction: see text] Water- and methanol-swollen Nafion membranes were used as microreactors to successfully control the photochemical reaction pathway of stilbazole derivatives. Of particular interest is the production of azaphenanthrene (the product not obtainable in homogeneous solution) in high yield under high bulk concentration. 相似文献