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951.
952.
In order to identify the potential nephrotoxic compounds in traditional Chinese medicine Lithospermum erythrorhizon,it was separated into serial fractions according to their polarities.An in vitro method was utilized to determine the nephrotoxicity of these fractions with the help of fluorescence image analysis.As a result,the primary fraction A05 and its secondary fractions C06 C09 and C12 C14 were found to have significant toxicity to LLC-PK1 cell line,as determined by the survive rate less than 20% after...  相似文献   
953.
The semi-conductive performances of hot growth film on 316L stainless steel were studied by means of electrochemical impedance spectroscopy(EIS) and Mott-Schottky analysis.The chemical compositions of the hot growth films were detected by X-ray photoelectron spectroscopy(XPS).The results show that the transfer resistance and film resistance increase with increasing temperature to 400℃,then they decrease sharply with further continuously increasing temperature.Formation time plays an important role in determ...  相似文献   
954.
A novel copolymer network with acetal structure was prepared using bis[4-(vinyloxy)butyl](4-methyl-1,3-phenylene)biscarbamate(BECT)as the crosslinking agent.Firstly,a tri-copolymer of maleic anhydride(MAn),n-butyl vinyl ether(BVE)and 4-hydroxybutyl vinyl ether(HBVE)was synthesized via free-radical polymerization with 2,2′-azobisisobutyronitrile as the initiator.The tri-copolymer consisted of two sorts of alternating units,MAn-alt-BVE and MAn-alt-HBVE.The linear copolymer Poly((MAn-alt-BVE)-co-(MAn-alt-HBVE)...  相似文献   
955.
Three two-dimensional like conjugated copolymers PFSDCN,PFSDTA and PFSDCNIO,which consist of alternating fluorene and triphenylamine main chain,and different pendant acceptor groups (malononitrile,1,3-diethtyl-2-thiobarbituric acid and 2-(1,2-dihydro-1-oxoinden-3-ylidene)malononitrile) with thiophene as π-bridge,have been designed,synthesized and characterized.The structure-property relationships of the two-dimensional like conjugated copolymers were systematically investigated.The absorption spectra,band g...  相似文献   
956.
With the development of colloid interface and enzyme technologies,enzyme-containing reversed micellar system has been receiving much attention in bioseparation and bioconversion. Because of its high efficiency,it has brought new opportunities for the development of molecular biotechnology. Reversed micelles represent nano-sized aqueous droplets stabilized by surfactant amphiphiles inside the bulk organic solvents. The entrapped enzymes have enhanced activities under those conditions as suited in the lipid b...  相似文献   
957.
The mechanisms of the acid-catalyzed decarboxylation of pyrrole-2-carboxylic acid and mesitoic acid have been investigated based on density functional theory calculations at the B3LYP/6-311G (d,p) level. A polarizable continuum model (PCM) has been established in order to evaluate the effects of solvents on these reactions. The results of the calculations indicate that the first step of the acid-catalyzed decarboxylation of the pyrrole-2-carboxylic acid has two possible pathways,that is,the proton of H3O+ a...  相似文献   
958.
Catalytic CO oxidation on platinum group metals exhibits nonlinear phenomena such as hysteresis and bifurcation.Elucidation of the nonlinear mechanisms is important for catalyst design and control of reaction routes.Previous studies have offered initial insights into the local bifurcation behavior of CO oxidation.However,since the bifurcation behavior of CO oxidation is determined by multiple parameters such as temperature,total flux,and CO fraction,it is difficult to predict the global bifurcation behavior...  相似文献   
959.
The algicidal activity of the terrestrial plants is a novel and promising means for alga control of eutrophic waters.In this study,three compositae plants — Artemisia annua(A.annua),Conyza canadensis(C.canadensis),and Erigeron annuus(E.annuus) were selected and antialgal activity of petroleum ether(PE),ethyl acetate(EA) and ethanol extracts of these plants on blue algae Microcystis aeruginosa was investigated.The result shows the EA extracts of these plants present the stronger inhibitory effects.The result...  相似文献   
960.
Pickering乳滴模板法制备有机/无机杂化的核壳微球越来越引起人们的关注,主要因为该方法制备出的微球具有以无机粒子为壳层的超粒子结构(supracolloidal structure),能够赋予微球独特的功能.胶体粒子在乳滴表面自组装形成有序的球面胶体壳,得到稳定Pickering乳液,固定乳滴表面的胶体粒子来制备核壳结构的微球或者以胶体粒子为壳层的微胶囊(colloidosome).本文综述了我们课题组以Pickering乳滴模板法制备超粒子结构有机/无机杂化微胶囊包括实心微球方面的工作.我们选择具有不同性能、种类的胶体粒子以及具有不同性质和功能的核材料,采用Pickering乳滴模板法,对吸附在乳滴表面的胶体粒子用不同的固定方法制备具有不同结构和性能的微球和微胶囊,利用基于多重Pickering乳液的聚合技术制备双纳米复合的超粒子结构多核聚合物微球.  相似文献   
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