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以N-苯甲酰基-N'-芳基硫脲和氯化铜为原料,在乙醇中合成了4种未见报道的标题配合物,通过元素分析、红外、紫外及荧光光谱和循环伏安法等对配合物进行了表征,初步确定其组成为[Cu(L)2Cl2]并推测了结构。对金黄色葡萄球菌、枯草芽孢杆菌以及大肠杆菌的抑菌活性测试结果表明,合成的4种配合物均有抑菌活性,且抑菌活性强于相应的配体,其中苯环上为双甲氧基取代的配体及其与铜的配合物对金黄色葡萄球菌的抑制能力强于其他配合物和配体。实验还发现配体的抑菌活性随配体取代基推电子能力呈规律性变化,配体中推电子取代基的数目和推电子能力是影响配合物抑菌活性的主要因素。 相似文献
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[目的]研究水溶性壳聚糖及其稀土离子金属配合物的抑菌活性。[方法]合成水溶性壳聚糖和稀土离子La(Ⅲ)、Ce(Ⅲ)、Nd(Ⅲ)的配合物,利用FT-IR、UV-Vis和热重分析仪对配合物进行表征,研究壳聚糖及其配合物对芦笋茎枯病菌Phomopsis asparagus的抑制活性。[结果]壳聚糖Ce(Ⅲ)配合物对Phomopsis asparagus的抑菌活性较单一的水溶性壳聚糖及其他稀土配合物显著提高。[结论]水溶性壳聚糖稀土配合物抑菌活性分别为Ce(Ⅲ)配合物>La(Ⅲ)配合物>Nd(Ⅲ)配合物>壳聚糖。 相似文献
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为研究酰腙类配合物的抑菌活性,以水杨酸甲酯、水合肼、呋喃甲醛为原料,无水乙醇为溶剂,在回流条件下合成了呋喃甲醛水杨酰腙(C12H10N2O3简称HL),再将HL和稀土硝酸盐反应,合成了RE(HL)2(NO3)3(RE=Pr,Eu,Tb,Y)4种稀土配合物。采用容量分析、元素分析、红外、紫外和摩尔电导率对配体及配合物的组成和结构特性进行了表征。选取配体HL及其与稀土Pr(Ⅲ)的配合物对辣椒疫霉菌、棉花枯萎病菌、烟草赤星菌进行了抑菌活性实验。结果表明:HL及Pr(HL)2(NO3)3配合物对棉花枯萎病的抑菌活性不明显(抑制率<70%),配体对辣椒疫霉、烟草赤星菌的抑菌率分别为71.0%和82.5%,而配合物为73.0%和85.9%。配合物的抗菌活性高于配体。 相似文献
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苯乙烯是重要的石油化工原料。本文介绍了国内外苯乙烯生产的发展概况,合成乙苯,苯乙烯所用的催化剂种类,并就苯乙烯生产及催化剂的发展趋势提出了自己的观点。 相似文献
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Synthesis and characterization of homopolymers and copolymers of various acrylates and acrylonitrile
Various homopolymers and copolymers of methyl acrylate, ethyl acrylate, butyl acrylate, and acrylonitrile in different feed ratios were synthesized. These were characterized by IR, 13C-NMR, DSC, DTA, and TGA. Spectroscopic characterization helped in differentiating copolymers of different mol ratios. Thermal analysis revealed different degradation patterns for homopolymers and copolymers. The temperature and energy changes associated with various phase transitions were dependent on the chemical composition of homo- and copolymers, as expected. © 1993 John Wiley & Sons, Inc. 相似文献
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责任是人应主动承担的角色义务和对其因过失所造成后果应承担的责罚.有两层涵义:一是义务;二是后果.责任心是个体自觉做好分内事务和履行道德义务的心理倾向,是个性心理品质成分中自我特征维度上的重要内容.责任心具有两个方面的涵义:一是角色分内职责;二是角色道德义务.责任心是一种通过责任认知、责任个性和责任适应的动态形式表现出来的静态品质,责任心是责任心过程结构与责任心关系结构相互制约、相互影响的统一体. 相似文献
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G. R. Hamed 《The Journal of Adhesion》1983,16(1):31-39
A substantially greater detachment energy is required to strip a polyethylene tereph-thalate (Mylar) film from a styrene-butadiene-styrene (SBS) triblock copolymer compared to that for peeling from a random styrene-butadiene (SBR) copolymer. This is true even though the intrinsic interaction between the Mylar and each elastomer is expected to be similar because of their virtually identical chemical composition. It is proposed that this difference in peel strength (between the SBS and SBR) is a consequence of the much higher dissipative capacity of the former elastomer. Another manifestation of this is the higher cohesive tear strength of the SBS compared to the SBR. Extents of energy dissipation within each elastomer during detachment of the Mylar adherend are consistent with the hypothesis that the average maximum stress experience before detachment is some similar fraction of each elastomer's tensile strength. 相似文献
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《国际聚合物材料杂志》2012,61(1-4):113-122
Abstract Kinetics and mechanisms of oxidation of 6 acetals by molecular oxygen and ozone in liquid phase have been studied. Reaction with molecular oxygen (70°C, 15–16 hr) leads to the formation monoethers of the corresponding glycols with 68–90% selectivity. Salts of metals and complexes with crown-ethers have increased the reaction rate significally. Ozone have reacted with acetals with formation similar products. The mechanisms of intermediate stages have been proposed. 相似文献
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The variation of the Au 4f binding energy of Au clusters with the cluster size has been established by measuring the binding energies of clusters whose size distributions were independently determined by HREM and STM. The binding energy increases significantly when the cluster size is less than 2 nm. Au-Cu bimetallic clusters of the composition Cu3Au have been deposited for the first time on carbon substrates. The shifts in the core level binding energies of the bimetallic clusters show the effect of alloying in the case of large clusters, but show effects of both alloying and cluster size in the case of the small clusters. The interaction of CO with Cu3Au clusters is stronger than with a bulk Cu metal. The interaction of CO with small Cu clusters also seems to be stronger than with bulk Cu or with large Cu clusters. 相似文献
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Polypentafluorostyrene (PPFS), polymethylacrylate (PMA), and poly(pentafluorostyrene-co-methylacrylate), poly(PFS-co-MA) were prepared and the wetting characteristics of polymer blends of PPFS and PMA were compared with that of poly(PFS-co-MA) via contact angle measurements. The critical surface tension of polypentafluorostyrene was found to be 22.6 dyne/cm, which is comparable to the value reported for polytrifluoroethylene (22 dyne/cm). The critical surface tension of poly(PFS-co-MA) is not linearly related to its composition. The polymer blends of PPFS and PMA exhibit significant surface enrichment of the fluoropolymer. The harmonic-mean method1 was employed to determine surface tensions of these polymers and many known polymers. It is found that the method produces useful surface tension data provided the contact angle values are derived from testing liquids of dissimilar polarity. 相似文献