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meso-5,10,15,20-四(取代2-噻吩基)卟啉及其配合物的合成与表征 总被引:5,自引:0,他引:5
用混合溶剂法合成了中位噻吩基取代的卟啉化合物:meso-四(2-噻吩基)卟啉 ,meso-四(4-溴-2-噻吩基)卟啉和meso-四(3-甲基-2-噻吩基)卟啉,产率达到36. 5%-39.3%,考察了溶剂的配比、反应温度、反应时间等因素对反应的影响,其 最佳反应条件为:溶剂配比:丙酸:乙酸:硝基苯:2:2(or3):1;反应温度: 130~140t;反应时间:50-60min.研究了利用固相合成法合成上述卟啉化合物与过 渡金属盐形成配合物的配位反应,在40℃利用固相合成法合成了卟啉化合物与 Fe2' Fe~3+,CO~2+,Ni~2+,Mn~2+等过渡金属离子形成的配合物,产率为81.1 %~87.6%.利用元素分析,UV-vis,m,'HNMR, HRMS对卟啉化合物及其配合物 进行了表征,利用TG-DTA研究了它们的热稳定性,利用EPR研究了它们的顺磁性. 相似文献
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以具有热敏性能的N-异丙基丙烯酰胺及其衍生物的共聚物作载体,利用温度为相分离的控制手段,在水介质中合成了2-氨基-3-氰基-4-取代苯基-5-甲氧羰基-4H-喃化合物,其结构经^1H NMR,IR和元素分析确证。 相似文献
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针对中学化学“物质结构与性质”模块3个版本教材中有关石英结构的二维图形不利于教学的局限性,利用“晶体学开放数据库”数据制作α-石英晶体结构三维虚拟模型,借助三维虚拟技术强大的交互功能全方位探索α-石英的空间结构,展示α-石英独特的大半径双螺旋手性结构,揭秘其旋光性的原因。教学实践表明,利用三维虚拟技术拓展中学结构教学的广度和深度是可行的。 相似文献
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目的通过测定8批复方木鸡颗粒中无机元素的含量,拟从无机成分的角度探讨复方木鸡颗粒的特征元素。方法采用电感耦合等离子体质谱仪(ICP-MS),以半定量分析的方式测定8批次复方木鸡颗粒无机元素的含量,建立复方木鸡颗粒无机轮廓谱,并对其差异元素中的重金属元素和人体有益元素进行全定量测定,同时,采用聚类分析和主成分分析,对其特征元素进行评价。结果构建了复方木鸡颗粒无机元素的轮廓谱,通过聚类分析和主成分分析共找到6个特征元素,包括Ca、Mg、Mn、K、Cr、Ni。结论从无机成分的角度明确了复方木颗粒的特征元素,为进一步探究复方木鸡颗粒的药效研究提供理论依据。 相似文献
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合成了新化合物2,4,6-三(对甲氧基苯乙烯基)-1,3,5-均三嗪(TMST);利用红外光谱、元素分析和核磁共振(1 H NMR)分析了化合物的组成和结构,利用紫外和荧光光谱分析了其光谱特征.结果表明,在375nm的紫外光激发下,化合物在410~480nm区域发出较强的蓝光,对应于叶绿素a的主吸收峰;这表明其可望作为一种新的蓝光光转换剂而应用于农用薄膜. 相似文献
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Gröger T Welthagen W Mitschke S Schäffer M Zimmermann R 《Journal of separation science》2008,31(19):3366-3374
In tobacco research, the comparison of different tobacco blends as well as the puff-dependent behaviour of cigarettes is a matter of particular interest. For the investigation of smoke characteristics, GC x GC offers different ways for data analysis, namely, compound target analysis, automated peak-based compound classification and comprehensive pixel-based data analysis. This study will show the application as well as the pros and cons of these types of data analysis for very complex matrices like cigarette particulate matter. In addition, new aspects about the recently discovered puff-dependent behaviour of compounds in cigarette smoke will be presented. Automated peak-based compound classification including mass spectrometric pattern recognition is used for the classification of tobacco particulate matter samples and the puff-dependent investigation of different compound classes. This compound group specific analysis is further reinforced by applying an even more comprehensive pixel-based analysis. This kind of analysis is used to generate fingerprints of different types of cigarettes. The combination of fast feature reduction methods like analysis of variance (ANOVA) and t-test with multivariate feature transformation methods like partial least squares discriminate analysis (PLSDA) for feature selection provides a powerful tool for a detailed inspection of different types of cigarettes. 相似文献
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J. Zhang Y. Y. Liu J. L. Zeng F. Xu L. X. Sun W. S. You Y. Sawada 《Journal of Thermal Analysis and Calorimetry》2008,91(3):861-866
Zinc formate dihydrate has been synthesized and characterized by powder X-ray diffraction, elemental analysis, FTIR spectra
and thermal analysis. The molar heat capacity of the coordination compound was measured by a temperature modulated differential
scanning calorimetry (TMDSC) over the temperature range from 200 to 330 K for the first time. The thermodynamic parameters
such as entropy and enthalpy vs. 298.15 K based on the above molar heat capacity were calculated. The thermal decomposition characteristics of this compound
were investigated by thermogravimetric analysis (TG) and differential scanning calorimetry (DSC). TG curve showed that the
thermal decomposition occurred in two stages. The first step was the dehydration process of the coordination compound, and
the second step corresponded to the decomposition of the anhydrous zinc formate. The apparent activation energy of the dehydration
step of the compound was calculated by the Kissinger method using experimental data of TG analysis. There are three sharply
endothermic peaks in the temperature range from 300 to 650 K in DSC curve. 相似文献
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β—环糊精对D/L—酪氨酸对映体的手性识别及超分子包合物的合成 总被引:6,自引:0,他引:6
利用圆二色谱研究了β-环糊精(β-CD)对D/L酪氨酸的手性识别行为,制备出了β-CD与L-酪氨酸(L-Tyr)的固体超分子化合物,并用元素分析、薄层分析、X射线粉末衍射及热分析对包合物进行了表征,用荧光光谱法测定了包合物的形成常数.实验结果表明,β-CD具有选择包结L-酪氨酸的特性;主客体形成11的包合物,其组成为L-Tyr/β-CD·12H2O;稳定常数为5.13×103L/mol;包合物的热稳定性比主客体皆有改善 相似文献
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The characterization of structure-activity relationship (SAR) features of large compound data sets has been a hot topic in recent years, and different methods for large-scale SAR analysis have been introduced. The exploration of local SAR components and prioritization of compound subsets have thus far mostly relied on graphical analysis methods that capture similarity and potency relationships in a systematic manner. A currently unsolved problem in large-scale SAR analysis is how to automatically select those compound subsets from large data sets that carry most SAR information. For this purpose, we introduce a numerical optimization scheme that is based on particle swarm optimization guided by an SAR scoring function. The methodology is applied to four large compound sets. We demonstrate that compound subsets representing the most discontinuous local SARs are consistently selected through particle swarm optimization. 相似文献
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2-甲基-1-(4-芳基噻唑-2-基)-苯并咪唑-6-甲酸乙酯的合成、表征及生物活性 总被引:2,自引:0,他引:2
以4-乙酰氨基苯甲酸乙酯为原料设计合成了14 种2-甲基-1-(4-芳基噻唑-2-基)-苯并咪唑-6-甲酸乙酯新化合物. 化合物结构经质谱、1H NMR、红外光谱和元素分析等确证, 并用单晶X射线衍射仪测定了化合物5a的晶体结构. 生物活性实验结果表明, 化合物5c(500 mg/L)对小麦白粉病菌抑制率达到95%; 化合物5e对辣椒疫霉病菌(25 mg/L)的抑制率为61.9%, 对油菜菌核病菌(500 mg/L) 抑制率高达97.2%; 化合物5k(25 mg/L) 对小麦赤霉病菌抑制率为55.1%. 相似文献
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采用水热方法并以邻菲啉为模板剂合成了一种过渡金属配合物连接的无机-有机层状结构的多金属钒酸盐Co(1,10-phen)(H2O)(VO3)2,该化合物经过X-射线单晶衍射、元素分析、红外光谱表征和热失重分析,并用循环伏安法研究了标题化合物的电化学性质. 相似文献
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2-(取代哌嗪-1-甲基)-3-喹啉甲酸乙酯及其衍生物的合成、 表征及晶体结构 总被引:1,自引:0,他引:1
以邻硝基苯甲醛为起始原料, 经还原、Friedländer 缩合反应合成2-甲基-3-喹啉甲酸乙酯(2), 2经N-溴代丁二酰亚胺(NBS)溴代得到化合物3, 3再与N-取代哌嗪5a~5p 发生SN2亲核取代反应, 合成一系列2-(取代哌嗪-1-甲基)-3-喹啉甲酸乙酯及其衍生物6a~6p. 它们的结构通过元素分析, IR, 1H NMR, 13C NMR和MS进行了鉴定和表征, 并用X射线衍射法测定了化合物6n的晶体结构. 相似文献