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应用灰色系统理论,推导出灰色N参数模型CGM(1,1,N),突破了现有单参数灰色模型的局限性,并用该模型讨论了色谱保留值与分子结构参数间绎烷基苯的同分异构体色谱保留值及疏水性参数进行了预测,经实例验证,其预测精度较单参数灰色模型高,这为溶质保留行为的预测提供了一个实用方法,同时也拓宽了灰色模型的应用范围。 相似文献
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应用灰色系统理论,推导出灰色N参数模型CGM(1,1,N),突破了现有单参数灰色模型的局限性.并用该模型讨论了色谱保留值与分子结构参数间的关系,对烷基苯的同分异构体色谱保留值及疏水性参数进行了预测.经实例验证,其预测精度较单参数灰色模型高,这为溶质保留行为的预测提供了一个实用方法,同时也拓宽了灰色模型的应用范围. 相似文献
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应用灰色系统理论和最小二乘原理,推导出连续GM(1,N)模型,并将该模型用于高效液相色谱中溶质保留行为的预测.研究了烷烃、烷基苯及对羟基苯甲酸酯等化合物的容量因子与流动相组成、容量因子与碳数、保留时间与温度、保留时间与碳数的关系,并建立了相应的数学模型,经验证,预测结果良好. 相似文献
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液相色谱中一个新的表征参数Z:Ⅱ.反相液相色谱中小分子极性溶质体系 总被引:3,自引:2,他引:3
反相高效液相色谱(RPLC)中小分子极性溶质的极性是可以用液相色谱中溶质计量置换保留模型中的Z值(1mol溶质被固定相吸附时,在固定相与溶质子间释放出置换剂的mol数)来表征的,其大小可用带有该极性端基的同系物的Z值对碳原子数线性作图的截距求得。这些检性基的Z测量定值与疏水性片段指数1gf间有极好的线性关系。依此关系还可测出一些用其他实验方法无法测得的某些基团的1gf值。 相似文献
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连续型非等时空距灰色模型在液相色谱保留值研究中的应用 总被引:12,自引:2,他引:12
本运用灰色理论中的连续型等时空距GM(1,1)模型,对液相色谱中流动相组成与容量因子间的关系进行了研究,建立了可进行连续预测的数学模型,所建模型与实际情况吻合很好,经检验各模型精度均达到I级。 相似文献
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灰色理论在液相色谱保留值研究中的应用 总被引:13,自引:4,他引:13
本文应用灰色理论中的GM(1,1)模型,对液相色谱中的Ф和k'的关系进行了研究,其结果达到用Schoenmakers公式和卢佩章公式预测及计算k'的水平。结果指出:灰色理论完全适用于对色谱保留问题的研究,其方法也这无全能满足实际工作中的应用。 相似文献
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反相液相色谱中生物大分子保留自由能及相比的测定 总被引:1,自引:0,他引:1
依据液相色谱中溶质的计量置换保留模型(SDM-R)和反相液相色谱(RPLC) 中小分子溶质柱相比的热力学新定义,建立了准确测定生物大分子柱相比的理论模 型和实验方法,准确测定了生物大分子的柱相比。同时依据计量置换参数logI和Z 具有热力学平衡常数的性质,并以logI和对1/T作图呈线性为途径,解决了生物大 分子色谱热力学研究中存在的三个难题,准确测定了七种标准蛋白质在RPLC保留过 程中的自由能变,并发现在RPLC中柱相比对保留过程中溶质总自由能变的贡献值几 乎可与溶质在RPLC保留过程中的净自由能变相当。 相似文献
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利用分子力学和量子化学方法计算出烷基苯类化合物的分子结构描述参数,用逐步回归法建立烷基苯类化合物在不同极性色谱柱上的QSRR模型。烷基苯类化合物在不同极性色谱柱上的气相色谱保留指数与其分子结构描述参数之间具有较好的线性关系。建立了在不同极性色谱柱上的烷基苯类化合物的色谱保留QSRR模型,并预测烷基苯类化合物的色谱保留值,结果具有较好的稳定性和准确性。 相似文献
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烃类化合物在不同色谱柱上的定量结构-保留相关性研究 总被引:4,自引:0,他引:4
运用量子化学中的AMI方法计算烃类化合物的分子结构描述参数,借助逐步回归法建立了烃类化合物在不同极性色谱柱上的QSRR模型。结果表明:烷烃、烯烃、二烯烃类化合物在不同极性的色谱柱上的色谱保留与其分子结构描述参数之间具有较好的线性关系,烃类化合物在不同极性固定相上的保留主要与溶质分子的MR有关,即与溶质分子的色散力有关。随着溶质分子的不饱和度的增加,或固定相极性的增强,溶质分子与固定相之间的电荷传递作用随之增强。而且,烃类化合物在不同极性固定相上的色谱保留的QSRR模型均可用量化参数HOMO、LUMO、EICE以及MR参数来描述。所建立的在不同极性色谱柱上的烃类化合物的色谱保留QSRR模型预测烃类化合物的色谱保留值时具有较好的稳定性和准确性。 相似文献
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Conclusions Equations are proposed for the calculation of the accuracy in the determination of the relative activity coefficients, the differences in partial molar excess enthalpies, entropies, and free energies of solution from the retention indexes. The calculation gives an error of the same order of magnitude as the gas-chro-matographic method of determination from the specific retention volumes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 658–600, March, 1972. 相似文献
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P. Jandera 《Chromatographia》1984,19(1):101-112
Summary A method based on the use of the members of homologous series as the calibration standards is suggested for prediction of
retention in reversed-phase liquid chromatography. The method respects the dependence of retention on the composition of the
mobile phase and makes possible distinguishing between the contributions of non-specific (hydrophobic) and specific (polar)
interactions to the retention. The selection of calibration homologous series is described, the method is verified for a number
of compounds and compared to the calculations based on the model of interaction indexes. The method suggested can be used
for prediction of retention in mobile phases with different compositions and for the optimization of separation conditions.
Presented at the 15th International Symposium on Chromatography, Nürnberg, October 1984 相似文献
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Conclusions Equations are proposed for evaluating the accuracy in the determination of the relative distribution coefficients, separation factors, differences in partial molar enthalpies, entropies, and free energies of solution from retention indexes which give an error of the same order of magnitude as the gas-chromatographic method of determination from specific retention volumes.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 3, pp. 632–635, March, 1972. 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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The retention of small peptides can be predicted by summing the hydrophobic contribution to retention of each amino acid of
peptides. But the retention time of peptides larger than 10–15 residues are less than that predicted by summing the retention
coefficients of each constitutive residue. A new prediction model, considering the effects of the peptide length and contact
area of each amino acid with the stationary phase for larger peptides was proposed. The model was validated by 136 peptides
identified by nano-flow 2-D-LC-ESI-MS-MS platform and other retention data observed from literature. The high degree of correlation
between the observed and predicted retention time by using the new model is not only good evidence for the accuracy of our
predictive method, but supports the supposition that the peptide length and contact area of each amino acid with stationary
phase are important factors affecting peptide retention time for larger peptide. In addition it is found that the range of
peptide length is wider, the accuracy of prediction is better. The ratio coefficient of surface area of non-polar, polar and
charged amino residues contacting with the stationary phase were all calculated to be less than one.
Revised: 30 June and 11 August 2005 相似文献
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甲基烷烃结构与色谱保留指数相关性的拓扑指数法研究 总被引:14,自引:0,他引:14
计算了207个甲基烷烃的127个拓扑指数变量,把变量选择方法GAPLS方法引入到定量结构与气相色谱保留关系研究中,对127个拓扑指数变量进行选择,得到了含7个变量的化合物的定量结构与色谱保留指数关系(QSRR)模型,其复相关系数的平方为0.99998,标准偏差为2.88。交互验证的复相关系数为0.99997,交互验证的预测标准偏差为2.95,表明该模型具有良好的稳定性和可靠性。对获得的7个变量进行了合理的结构解释,表明甲基烷烃色谱保留指数完全能用拓扑指数来精确表征。 相似文献