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硫醇的分子连接性指数与气相色谱保留值 总被引:1,自引:0,他引:1
硫醇的分子连接性指数与气相色谱保留值赵邦屯王利亚(洛阳师专化学系洛阳471022)关键词硫醇分子连接性指数气相色谱保留值中图分类号O657.71有机化合物的色谱保留行为与其结构之间的定量关系研究一直是物理化学、分析化学和生物化学的研究对象之一。长期以... 相似文献
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1引言 作为结构-性质定量关系(QSPR)研究领域的一个重要分支,定量结构-色谱保留值相关(QSRR)的研究和应用在色谱科学领域受到关注。QSRR的研究对预测保留值、选择分离条件及探索色谱保留机理都具有重要意义。影响气相色谱相对保留值的因素很多,但主要是与被测组分和固定相之间的分子间作用能有关。而分子间的作用能主要由分子间的色散力决定,分子的色散力与分子的分支情况及体积大小有关。 相似文献
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烷基吡啶保留指数与分子结构的关系 总被引:5,自引:0,他引:5
分子连通指数是Randic提出描述分子中原子间连接特征(如型状、分子骨架结构)的参数,分子的许多性质如沸点、自由能等都和连通指数存在线性关系,气相色谱保留值在非极性固定液上也与分子连通指数有着线性关系,但用连通指数预示异构 相似文献
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从分子微观参数预测反相色谱保留值方程系数 总被引:8,自引:1,他引:7
在考虑氢键作用能随流动相组成改变的情况下,重新推导了液相色谱保留值方程,进而得到液相色谱保留值方程系数与分子微观参数之间的关系。在分子母体结构相同条件下,提出采用五个系数预测反相色谱保留值的方法,并用文献数据给予验证。 相似文献
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氮杂冠醚聚硅氧烷固定液的色谱保留机理 总被引:3,自引:0,他引:3
氨杂冠醚聚硅氧烷是一类呈中等极性的新颖气相色谱固定液.本文通过测定醇、酯、卤代烃和苯系列化合物的色谱保留值和相应势力学参数,研究它对上述不同化合物的保留机理及其分子识别的热力学性质 相似文献
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应用Benson基团加和法,对脂肪醇、醛、酮和酯几类有机化合物的分子结构与气相色谱保留值间的关系进行了研究,对部分化合物气相色谱保留值的预测结果表明,这几类化合物的气相色谱保留值具有很好的基团加和性,预测值与实验值吻合很好。 相似文献
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陈丽 《理化检验(化学分册)》2007,43(4):287-289
考虑到气相中溶质分子和其它成分在固定相上的竞争吸附作用,提出了一个描述溶质在气相色谱中进样量和保留值的关系式.由此方程可以获得两个描述色谱体系特征的重要参数:溶质和其它成分在固定相表面竞争吸附的热力学平衡常数Ka和单位体积固定相所能吸附溶质的量NmS.当其它参数给定时,Ka的大小直接决定溶质进样量与保留值关系式的性质.通过试验对此方程进行了初步验证. 相似文献
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应用半经验量子化学AM1方法得到了108种含氧有机分子的优势构象,利用AM1方法和分子图形学技术获得了它们的电子结构和几何结构参数,并将这些参数与脂水分配系数相关联,采用逐步回归分析方法,成功地建立了拟合度高、物理意义明确、预测能力强的含氧有机分子脂水分配系数-结构参数定量关系方程,找出了影响含氧有机分子脂水分配系数的主要结构因素. 相似文献
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Molecular structures of polychlorinated naphthalenes were numerically described with a simple but efficient encoding method. Correspondingly a set of structural parameters were obtained for these compounds and linearly correlated with their gas chromatography retention indexes. A quantitative structure‐retention relationship Model (M1) was developed by using multiple linear regression (MLR) with correlation coefficient R = 0.9880 between the numeric structural codes and the gas chromatography retention indexes of 62 polychlorinated naphthalenes. If the “leave‐one‐out” cross‐validation procedure was employed to construct QSPR model for all samples, the second model M2 with the correlation coefficient being R = 0.9839 was generated. The structural codes of polychlorinated naphthalenes were tested with MLR for estimation and prediction of the GC RI by models M1 and M2, and the results obtained were satisfactory. 相似文献
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应用分子电性距离矢量(MEDV)对114个多环芳香硫化合物(PASHs)进行结构表征,通过多元线性回归建立了PASHs的气相色谱保留指数与MEDV参数之间的定量结构-保留值关系模型;同时采用逐步回归分析进行变量筛选,继而以留一法交互检验对所得优化模型进行预测能力评价,所建立的模型的相关系数为0.9947,交互检验相关系数为0.9940,表明该优化模型具有良好的稳定性和预测能力。此外,通过将样本集按2:1分成校准集和测试集预测,统计分析结果显示所建的模型具有良好的相关性和稳定性。本文所建的定量结构-保留值关系(QSRR)模型为预测PASHs的气相色谱保留指数提供了一个便捷有效的新方法。 相似文献
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《Analytical letters》2012,45(3-4):375-384
Abstract Retention data for tetradentate metal complexes of copper and nickel are reported for microparticulate silica and reversed phase columns. An attempt is made to relate structure and stability constant data to the retention volume by means of multiple linear regression. The results indicate that if the structure is encoded by means of dummy variables it may be possible to predict retention volumes of metal complexes. There is not a strong correlation between the value of the stability constants for the metal diamine and metal ketone complexes and the retention volume. 相似文献
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Chemical structures of polychlorinated dibenzodioxin (PCDD) congeners are described by a novel molecular distance edge vector (VMDE), developed in our laboratory, that consists of the modified molecular distance edge parameters based on the identical group as a pseudo-atom instead of a traditional atom. Quantitative structure retention relationships (QSRRs) between the new VMDE parameters and the gas chromatographic retention behavior of PCDDs are then generated by a multiple linear regression method for nonpolar, moderately polar, and polar stationary phases. All QSRR models with a high correlation (R > 0.99) are developed for nonpolar, moderately polar, and polar columns (DB-5, SP-2100, SE-54, and OV-1701). Cross validation with the leave-one-out procedure is performed, and satisfactory results are obtained with high correlation. The obtained results show that the new VMDE vector is adapted to characterize the chemical structure and model the retention behavior of PCDDs on various polar stationary phases. 相似文献
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Quantitative structure–property relationships of retention indices of some sulfur organic compounds using random forest technique as a variable selection and modeling method 下载免费PDF全文
Nasser Goudarzi Davood Shahsavani Fereshteh Emadi‐Gandaghi Mansour Arab Chamjangali 《Journal of separation science》2016,39(19):3835-3842
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Jeanina Pandele Cusu Adina Magdalena Musuc Mihaela Matache Dumitru Oancea 《Journal of Thermal Analysis and Calorimetry》2012,110(3):1259-1266
In this study, the thermal stability and exothermal decomposition of some ketone-2,4-dinitrophenylhydrazones have investigated using the DSC technique. The synthesized and purified crystalline solids are thermally stable and start to decompose after melting. Non-isothermal DSC curves, recorded at several heating rates, were used to evaluate the melting properties and the kinetics of thermal decomposition. The isoconversional and model-fitting methods were applied to determine the activation parameters from the common analysis of multiple curves measured at different heating rates. Based on the results of the model??free method, a kinetic model was derived, and the kinetic parameters were obtained by means of a multivariate nonlinear regression. The results are discussed in relation to the effect of the ketone structure. 相似文献