在高效液相色谱(HPLC)测定方法的基础上,采用摇瓶法,准确测得25℃时16个取代苯硫酚类化合物的水溶解度(-lgSw)和19个正辛醇/水分配系数(lgKow)数据.采用密度泛函理论(DFT)中的B3LYP方法,在6-311G**基组上全优化计算得到24个取代苯硫酚...在高效液相色谱(HPLC)测定方法的基础上,采用摇瓶法,准确测得25℃时16个取代苯硫酚类化合物的水溶解度(-lgSw)和19个正辛醇/水分配系数(lgKow)数据.采用密度泛函理论(DFT)中的B3LYP方法,在6-311G**基组上全优化计算得到24个取代苯硫酚的结构参数和热力学参数,采用SPSS12.0 for windows程序,分别求得-lgSw和lgKow值与这些参数之间的相关方程,相关系数R2分别为0.958和0.946.用交叉验证法对方程的稳定性进行了验证(q2分别为0.925和0.930),并用t检验和变异膨胀因子(Variance Inflation Factors,VIF)对两个方程中各变量的显著性和自相关性进行了检验.结果表明:所建方程具有较强的预测能力,并用其预测了8个没有实验数据的取代苯硫酚的-lgSw值和5个lgKow值.展开更多
Polychlorinated diphenyl ethers(PCDEs) are listed as the so-called persistent pollutants.Atomic characteristic values of all 209 possible molecular structure patterns of PCDEs were calculated,then a new connectivity i...Polychlorinated diphenyl ethers(PCDEs) are listed as the so-called persistent pollutants.Atomic characteristic values of all 209 possible molecular structure patterns of PCDEs were calculated,then a new connectivity index,orientating corresponding index was calculated with the technique of molecule graphics.The orientating corresponding index was combined with five observed thermodynamic properties of PCDEs,i.e.molecular mean polarizability,standard enthalpy,free energy,heat capacity at constant volume and standard entropy,and fifteen quantitative structure-property relationship(QSPR) models(r>0.99)were obtained with the unitary linear regression method,and the relative mean deviations were 1.02%,0.48%,0.48%,0.22% and 0.90%,respectively.In order to test the stability and prediction ability of each model,the jackknifed cross validation was performed and good results(r>0.99)were obtained.These models can better elucidate the change of the thermodynamic properties for the PCDEs,and the QSPR models have satisfactory stability and good predictability.展开更多
文摘在高效液相色谱(HPLC)测定方法的基础上,采用摇瓶法,准确测得25℃时16个取代苯硫酚类化合物的水溶解度(-lgSw)和19个正辛醇/水分配系数(lgKow)数据.采用密度泛函理论(DFT)中的B3LYP方法,在6-311G**基组上全优化计算得到24个取代苯硫酚的结构参数和热力学参数,采用SPSS12.0 for windows程序,分别求得-lgSw和lgKow值与这些参数之间的相关方程,相关系数R2分别为0.958和0.946.用交叉验证法对方程的稳定性进行了验证(q2分别为0.925和0.930),并用t检验和变异膨胀因子(Variance Inflation Factors,VIF)对两个方程中各变量的显著性和自相关性进行了检验.结果表明:所建方程具有较强的预测能力,并用其预测了8个没有实验数据的取代苯硫酚的-lgSw值和5个lgKow值.
文摘Polychlorinated diphenyl ethers(PCDEs) are listed as the so-called persistent pollutants.Atomic characteristic values of all 209 possible molecular structure patterns of PCDEs were calculated,then a new connectivity index,orientating corresponding index was calculated with the technique of molecule graphics.The orientating corresponding index was combined with five observed thermodynamic properties of PCDEs,i.e.molecular mean polarizability,standard enthalpy,free energy,heat capacity at constant volume and standard entropy,and fifteen quantitative structure-property relationship(QSPR) models(r>0.99)were obtained with the unitary linear regression method,and the relative mean deviations were 1.02%,0.48%,0.48%,0.22% and 0.90%,respectively.In order to test the stability and prediction ability of each model,the jackknifed cross validation was performed and good results(r>0.99)were obtained.These models can better elucidate the change of the thermodynamic properties for the PCDEs,and the QSPR models have satisfactory stability and good predictability.