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Quantitative structure-activity relationship study on the biodegradation of acid dyestuffs 被引量:9
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作者 LI Yin XI Dan-li 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2007年第7期800-804,共5页
Quantitative structure-biodegradability relationships (QSBRs) were established to develop predictive models and mechanistic explanations for acid dyestuffs as well as biological activities. With a total of four desc... Quantitative structure-biodegradability relationships (QSBRs) were established to develop predictive models and mechanistic explanations for acid dyestuffs as well as biological activities. With a total of four descriptors, molecular weight (MW), energies of the highest occupied molecular orbital (EHOMO), the lowest unoccupied molecular orbital (ELUMO), and the excited state (EES), calculated using quantum chemical semi-empirical methodology, a series of models were analyzed between the dye biodegradability and each descriptor. Results showed that EHOMO and Mw were the dominant parameters controlling the biodegradability of acid dyes. A statistically robust QSBR model was developed for all studied dyes, with the combined application of EHOMO and Mw. The calculated biodegradations fitted well with the experimental data monitored in a facultative-aerobic process, indicative of the reliable prediction and mechanistic character of the developed model. 展开更多
关键词 quantitative structure-activity relationship (qsar acid dyestuff BIODEGRADABILITY DECOLORIZATION
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Predicting quantitative structure-activity relationship of substituted 17α-acetoxyprogesterones by molecular hybridization electronegativity-distance vector
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作者 SUN Li-Ii LAN Yu-kun +2 位作者 ZHOU Li-ping YU YU LI Zhi-liang 《Journal of Chongqing University》 CAS 2007年第2期79-87,共9页
A set of novel structural descriptors (molecular hybridization electronegativity-distance vector, VMEDh) was put forward, and the quantitative structure–activity relationship (QSAR) of a series of 17α-Acetoxyprogest... A set of novel structural descriptors (molecular hybridization electronegativity-distance vector, VMEDh) was put forward, and the quantitative structure–activity relationship (QSAR) of a series of 17α-Acetoxyprogesterones (APs) was investigated. Taking into account the effect of various hybridized orbits on atomic electronegativities, we developed the structure descriptors with amended electronegativities to build a QSAR model. The 10-parameter model based on VMEDh yields a correlation coefficient R=0.972 and standard deviation SD=0.262, which are more desirable than those of the previous molecular electonegativity-distance vector (MEDV-4) (R=0.969, SD=0.275). By stepwise multiple linear regression, several parameters are selected to construct optimal models. The 7-parameter model based on VMEDh has R=0.960 and SD=0.276; its correlation coefficient (RCV) and standard deviation (SDCV) for leave-one-out procedure crossvalidation are respectively RCV=0.890 and SDCV=0.445. The 6-parameter MEDV-4 model has R=0.946, SD=0.304, RCV=0.903 and SDCV=0.406. It is demonstrated that VMEDh has desirable estimation performance and good predictive capability for this series of chemical compounds. 展开更多
关键词 molecular hybridization electronegativity-distance vector quantitative structure-activity relationship (qsar 17α- Acetoxyprogesterones
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Genotoxicity of substituted nitrobenzenes and the quantitative structure-activity relationship 被引量:1
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作者 Huang Qingguo Liu Yongbin +1 位作者 Wang Liansheng Han Shuokui(Department of Environmental Science and Engineering,Nanjing University,Nanjing 210093,China)Yang Jun(Jiangsu Metallurgy Institute.Nanjing 210007,China) 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 1996年第1期103-109,共7页
The genotoxicity of 22 substituted nitrobenzenes were evaluated by the chromosome aberrations test in in vitro human peripheral lymphocytes.18 of 22 compounds exhibit genotoxic activities.Quantitative structure-activi... The genotoxicity of 22 substituted nitrobenzenes were evaluated by the chromosome aberrations test in in vitro human peripheral lymphocytes.18 of 22 compounds exhibit genotoxic activities.Quantitative structure-activity relationship model was established to correlate the genotoxicity of substituted nitrobenzenes with the characteristics of the substituents on benzene ring. 展开更多
关键词 quantitative structure-activity relationship(qsar) substituted nitrobenzenes genotoxicity.
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Quantum Chemical Study on Structure-activity Relationship of Several Kinds of Drugs
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作者 李小红 程新路 +1 位作者 张瑞州 杨向东 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第5期513-520,490,共9页
The structure-activity relationship of several drugs with similar structure has been investigated by using ab initio method. The relation between the dipole moments and biological activities of these drugs was judged ... The structure-activity relationship of several drugs with similar structure has been investigated by using ab initio method. The relation between the dipole moments and biological activities of these drugs was judged after comparing their geometric structures, dipole moments and inhibitory concentrations. In principle, new drug molecule could be reasonably designed by altering the place of groups and ultimately, the potential drug could be screened by comparing the dipole moments of obtained molecules. 展开更多
关键词 quantitative structure-activity relationship (qsar) dipole moment ab initio calculation biological activity
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Quantitative Structure Activity Relationship Studies of Benzoxazinone Derivative Antithrombotic Drug Using New Three-dimensional Structure Descriptors
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作者 仝建波 李云飞 +1 位作者 刘淑玲 孟元亮 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第12期1893-1899,共7页
A novel three-dimensional holographic vector of atomic interaction field(3D-HoVAIF) was used to describe the chemical structures of 23 benzoxazinone derivatives as antithrombotic drugs.Here a quantitative structure ... A novel three-dimensional holographic vector of atomic interaction field(3D-HoVAIF) was used to describe the chemical structures of 23 benzoxazinone derivatives as antithrombotic drugs.Here a quantitative structure activity relationship(QSAR) model was built by partial least-squares(PLS) regression.The estimation stability and prediction ability of the model were strictly analyzed by both internal and external validations.The correlation coefficients of established PLS model,leave-one-out(LOO) cross-validation,and predicted values versus experimental ones of external samples were R2=0.899,RCV2=0.854 and Qext2=0.868,respectively.These values indicated that the built PLS model had both favorable estimation stability and good prediction capabilities.Furthermore,the satisfactory results showed that 3D-HoVAIF could preferably express the information related to the biological activity of benzoxazinone derivatives. 展开更多
关键词 benzoxazinone derivatives antithrombotic drug three-dimensional holographic vector of atomic interaction field(3D-HoVAIF) quantitative structure-activity relationship(qsar
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QSAR/QSPR在POPs归趋与风险评价中的应用 被引量:15
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作者 王斌 余刚 +1 位作者 黄俊 胡洪营 《化学进展》 SCIE CAS CSCD 北大核心 2007年第10期1612-1619,共8页
持久性有机污染物(POPs)是目前备受国际社会关注的高危害性有机污染物,对它们的环境归趋分析和风险评价需要获得大量可靠的性质数据和毒性数据,而定量结构活性/性质相关(QSAR/QSPR)方法为快速有效地获得这些数据提供了可能性。QSAR/QSP... 持久性有机污染物(POPs)是目前备受国际社会关注的高危害性有机污染物,对它们的环境归趋分析和风险评价需要获得大量可靠的性质数据和毒性数据,而定量结构活性/性质相关(QSAR/QSPR)方法为快速有效地获得这些数据提供了可能性。QSAR/QSPR模型已在预测POPs的生物活性/性质,补充缺失的基础数据及探求POPs的环境过程机制和生态效应机理等方面得到了广泛应用。近年来其在新POPs物质的筛选、归趋模拟以及风险评价等方面有着更进一步的应用或潜在应用前景。本文介绍了QSAR/QSPR在POPs性质和生物活性预测中的基本应用及其在POPs归趋和风险评价中的扩展应用,并对QSAR/QSPR在POPs领域的应用前景进行了展望。 展开更多
关键词 定量结构活性/性质相关 持久性有机污染物 归趋 风险评价
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化合物分子的QSAR/QSPR研究 被引量:1
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作者 陈丽华 《汉中师范学院学报》 2004年第6期41-45,共5页
 对化合物的定量结构_活性 性质相关(QSAR QSPR)进行相关描述,重点介绍了QSAR QSPR研究的特点,并对化合物分子的QSAR QSPR的相关研究发展作了展望.
关键词 定量结构-性质相(qspr) 定量结构-活性相关(qsar) 研究特点 相关描述 发展展望
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Quantitative Correlation of Chromatographic Retention and Acute Toxicity for Alkyl(1-phenylsulfonyl) Cycloalkane Carboxylates and Their Structural Parameters by DFT 被引量:7
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作者 WANGZun-Yao HANXiang-Yun WANGLian-Sheng 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第7期851-857,740,共8页
Twenty eight alkyl(1-phenylsulfonyl) cycloalkane carboxylates were computed at the B3LYP/6-31G* level. Based on linear solvation energy theory, two quantitative correlation equations of the molecular structures of alk... Twenty eight alkyl(1-phenylsulfonyl) cycloalkane carboxylates were computed at the B3LYP/6-31G* level. Based on linear solvation energy theory, two quantitative correlation equations of the molecular structures of alkyl(1-phenylsulfonyl) cycloalkane carboxylate com- pounds to their chromatographic retention (capacity factor lgKW) and the toxicity for photo- bacterium phosphoreum (–lgEC50) were developed by using the molecular structural parameters as theoretical descriptors (r2 = 0.9501, 0.9488). The two quantitative correlation equations were consequently cross validated by leave-one-out (LOO) validation method with q2 of 0.9113 and 0.9281, respectively. The result showed that the two equations achieved in this work by B3LYP/6-31G* are both more advantageous than those from AM1, and can be used to predict the lgKW and –lgEC50 of congeneric organics. 展开更多
关键词 chromatographic retention acute toxicity photobacterium density functional theory method linear solvation energy theory quantitative structure-property relationship (qspr) quantitative structure-activity relationships (qsar)
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QSAR of Estrogen of Bisphenol A with 3D Vector of Atomic Property Correlation 被引量:2
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作者 CHEN Zhi-Tao ZHOU Peng +1 位作者 HE Liu LI Zhi-Liang 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2007年第8期988-994,共7页
Considering atomic property vector and atomic correlative function, the 3-dimensional structural vector of atomic property correlation (3D-VAPC), a novel descriptor,is defined to characterize a 3-dimensional molecul... Considering atomic property vector and atomic correlative function, the 3-dimensional structural vector of atomic property correlation (3D-VAPC), a novel descriptor,is defined to characterize a 3-dimensional molecular structure by introducing self-adaptability regulation mechanism and the idea of orientating to customers. Characterizing the structures of 25 bisphenol A compounds by this vector, the QSAR models of three kinds of estrogen activities (ER affinities, gene induction and cell proliferation) have high multiple correlation coefficient (Rcum^2=0.933, 0.813, 0.959) and cross verification coefficient (Qcum^2=0.847, 0.953, 0.798) by support vector machine (SVM), which suits for nonlinear circumstances. The above results show that the models successfully express the correlation between structure and three kinds of estrogen activities. Therefore, 3D-VAPC exactly reflects the molecular structural information and SVM method correctly describes the correlation between information and property of the compounds. 展开更多
关键词 3D vector of atomic property correlation (3D-VAPC) support vector machine (SVM) quantitative structure-activity relationship (qsar bisphenol A ESTROGEN
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Quantitative Correlation of the Acute Toxicity of Phenylthio-carboxylates with Their Structural and Thermodynamic Parameters by DFT Calculation 被引量:2
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作者 韩香云 王遵尧 杨春生 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第2期145-150,共6页
Phenylthio-carboxylates were computed at the B3LYP/6-31G* level with DFT method. Based on linear solvation energy theory, the structural parameters were firstly taken as theoretical descriptors, and the correspondin... Phenylthio-carboxylates were computed at the B3LYP/6-31G* level with DFT method. Based on linear solvation energy theory, the structural parameters were firstly taken as theoretical descriptors, and the corresponding linear solvation energy relationship (LSER) equation (r = 0.8989) to the toxicity of photobacterium phosphoreum (–lgEC50) was thus obtained. Then the structural and thermodynamic parameters were taken as theoretical descriptors, and as a result the other corresponding correlation equation (r = 0.9274) relating to –lgEC50 was provided. The two equations achieved in this work by B3LYP/6-31G* are both more advantageous than that from AM1. 展开更多
关键词 acute toxicity linear solvation energy theory DFT method quantitative structure-activity relationships (qsar) aquatic life
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Quantitative Models for the Structure and Photodegradation of Polycyclic Aromatic Hydrocarbons 被引量:2
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作者 周作明 李小林 荆国华 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2010年第2期205-212,共8页
Based on the quantum chemical descriptors,quantitative structure-property relationship(QSPR) models have been developed to estimate and predict the photodegradation rate constant(logK) of polycyclic aromatic hydro... Based on the quantum chemical descriptors,quantitative structure-property relationship(QSPR) models have been developed to estimate and predict the photodegradation rate constant(logK) of polycyclic aromatic hydrocarbons(PAHs) by use of linear method(multiple linear regression,MLR) and non-linear method(back propagation artificial neural network,BP-ANN).A BP-ANN with 3-3-1 architecture was generated by using three quantum chemical descriptors appearing in the MLR model.The standard heat of formation(HOF),the gap of frontier molecular orbital energies(ΔELH) and total energy(TE) were inputs and its output was logK.Leave-One-Out(LOO) Cross-Validated correlation coefficient(R^2CV) of the established MLR and BP-ANN models were 0.6383 and 0.7843,respectively.The nonlinear BP-ANN model has better predictive ability compared to the linear MLR model with the root mean square error(RMSE) for training and validation sets to be 0.1071,0.1514 and the squared correlation coefficient(R^2) of 0.9791,0.9897,respectively.In addition,some insights into the molecular structural features affecting the photodegradation of PAHs were also discussed. 展开更多
关键词 quantitative structure-property relationshipqspr) photodegradation rate constant(logK) polycyclic aromatic hydrocarbons multiple linear regression backpropagation artificial neural network
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Correlation of Quantitative Structure and Inhibition Phytotoxicity for Aromatic Compounds Using Ab Initio Method
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作者 戴勇 王遵尧 +1 位作者 乔旭 杨春生 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2005年第9期1054-1060,共7页
29 aromatic compounds were computed at the HF/6-31G^* level. Based on linear solvation energy theory firstly, the parameters of molecular structure were taken as theoretical descriptors, and the corresponding linear ... 29 aromatic compounds were computed at the HF/6-31G^* level. Based on linear solvation energy theory firstly, the parameters of molecular structure were taken as theoretical descriptors, and the corresponding linear solvation energy relationship (LSER) (r^2= 0.8993, q^2=0.8559) between the structural parameters and inhibition phytotoxicity to the seed germination rate of cucumis (-lgGC50) was thus obtained. Then the parameters of molecular structure and thermodynamics were taken as theoretical descriptors, and as a result the other corresponding correlation equation (r^2=0.9268, q^2=0.8960) relating to -lgGC50 was achieved. The two equations obtained in this work by HF/6-31G^* are both more advantageous than that from AM 1. 展开更多
关键词 aromatic compounds inhibition phytotoxicity linear solvation energy theory ab initio quantitative structure-activity relationships (qsar
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Molecular Structural Characterization and Quantitative Prediction of Reduced Ion Mobility Constants for Diversified Organic Compounds
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作者 何留 梁桂兆 李志良 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 北大核心 2008年第10期1187-1194,共8页
Based on two-dimensional topological structures, a novel molecular electronegativity interaction vector with hybridization (MEHIV) was developed to describe atomic hybridization state in different molecular environm... Based on two-dimensional topological structures, a novel molecular electronegativity interaction vector with hybridization (MEHIV) was developed to describe atomic hybridization state in different molecular environments. Five quantitative models by MEHIV characterization and multiple linear regression modeling were successfully established to predict reduced ion mobility constants (Ko) of alkanes, aromatic hydrocarbons, fatty alcohols, fatty aldehydes and ketones and carboxylic esters. The correlation coefficients Roy by leave-one-out cross-validation are 0.792, 0.787, 0,949, 0.972 and 0.981, respectively, and the standard deviations SDcv are 0.067, 0.086, 0.064, 0.043 and 0.042, respectively. These results suggested that MEHIV is an excellent topological index descriptor with many advantages such as straightforward physicochemical meaning, high characterization competence, convenient expansibility and easy manipulation. 展开更多
关键词 molecular electronegativity interaction veetur with hybridization (MEHIV) ion mobility spectrometry reduced ion mobility constants quantitative structure-property relationship qspr)
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Machine Learning-Based Quantitative Structure-Activity Relationship and ADMET Prediction Models for ERα Activity of Anti-Breast Cancer Drug Candidates 被引量:5
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作者 XU Zonghuang 《Wuhan University Journal of Natural Sciences》 CAS CSCD 2023年第3期257-270,共14页
Breast cancer is presently one of the most common malignancies worldwide,with a higher fatality rate.In this study,a quantitative structure-activity relationship(QSAR)model of compound biological activity and ADMET(Ab... Breast cancer is presently one of the most common malignancies worldwide,with a higher fatality rate.In this study,a quantitative structure-activity relationship(QSAR)model of compound biological activity and ADMET(Absorption,Distribution,Metabolism,Excretion,Toxicity)properties prediction model were performed using estrogen receptor alpha(ERα)antagonist information collected from compound samples.We first utilized grey relation analysis(GRA)in conjunction with the random forest(RF)algorithm to identify the top 20 molecular descriptor variables that have the greatest influence on biological activity,and then we used Spearman correlation analysis to identify 16 independent variables.Second,a QSAR model of the compound were developed based on BP neural network(BPNN),genetic algorithm optimized BP neural network(GA-BPNN),and support vector regression(SVR).The BPNN,the SVR,and the logistic regression(LR)models were then used to identify and predict the ADMET properties of substances,with the prediction impacts of each model compared and assessed.The results reveal that a SVR model was used in QSAR quantitative prediction,and in the classification prediction of ADMET properties:the SVR model predicts the Caco-2 and hERG(human Ether-a-go-go Related Gene)properties,the LR model predicts the cytochrome P450 enzyme 3A4 subtype(CYP3A4)and Micronucleus(MN)properties,and the BPNN model predicts the Human Oral Bioavailability(HOB)properties.Finally,information entropy theory is used to validate the rationality of variable screening,and sensitivity analysis of the model demonstrates that the constructed model has high accuracy and stability,which can be used as a reference for screening probable active compounds and drug discovery. 展开更多
关键词 anti-breast cancer drug discovery quantitative structure-activity relationship(qsar)model ADMET(Absorption Distribution Metabolism Excretion Toxicity)prediction machine learning
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Quantitative structure-activity relationship of compounds binding to estrogen receptor β based on heuristic method 被引量:3
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作者 ZHANG YiMing YANG XuShu +1 位作者 SUN Cheng WANG LianSheng 《Science China Chemistry》 SCIE EI CAS 2011年第1期237-243,共7页
Estrogen compounds may pose a serious threat to the health of humans and wildlife. The estrogen receptor (ER) exists as two subtypes, ERα and ERβ. Compounds might have different relative affinities and binding mod... Estrogen compounds may pose a serious threat to the health of humans and wildlife. The estrogen receptor (ER) exists as two subtypes, ERα and ERβ. Compounds might have different relative affinities and binding modes for ERα and ERβ. In this study, the heuristic method was performed on 31 compounds binding to ERβ to select 5 variances most related to the activity (LogRBA) from 1524 variances, which were then employed to develop the best model with the significant correlation and the best predictive power (γ^2 = 0.829, q^2LOO = 0.742, γ^2pred = 0.772, q^2ext = 0.724, RMSEE = 0.395) using multiple linear regression (MLR). The model derived identified critical structural features related to the activity of binding to ERβ. The applicability domain (AD) of the model was assessed by Williams plot. 展开更多
关键词 estrogen receptor β(ERβ) quantitative structure-activity relationship (qsar heuristic method applicability domain
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QSPR模型对AE_3SO_3表面活性剂的cmc计算及其分子中EO基团对胶束化的作用 被引量:7
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作者 王仲妮 王正武 +4 位作者 高艳安 郑利强 刘杰 李干佐 张高勇 《化学学报》 SCIE CAS CSCD 北大核心 2004年第24期2391-2397,共7页
合成并纯化了三种阴离子表面活性剂脂肪醇聚氧乙烯 (3 )醚磺酸钠AE3 SO3 [CnH2n+ 1(OE) 3 SO3 Na (n =12 ,14 ,16) ] .用我们建立的定量结构 -性质相关 (QSPR)模型预测它们的cmc值 ,其结果与表面张力测定的实验值相吻合 ;并用QSPR计算... 合成并纯化了三种阴离子表面活性剂脂肪醇聚氧乙烯 (3 )醚磺酸钠AE3 SO3 [CnH2n+ 1(OE) 3 SO3 Na (n =12 ,14 ,16) ] .用我们建立的定量结构 -性质相关 (QSPR)模型预测它们的cmc值 ,其结果与表面张力测定的实验值相吻合 ;并用QSPR计算分子中嵌入 0~ 5个EO基团的C12 ESO3 的cmc值 ,表明EO具有疏水性 .从Klevens经验公式和有机概念图均得出 ,EO链对AE3 SO3 疏水性的贡献随烷基链长增加 (n =12~ 16)而逐渐减弱 ,3个EO基团分别相当于 2 .4,2 .3 ,2 .2个CH2 的疏水作用 .热力学计算表明 ,在C12 SO3 中引入第 1个EO后 ,胶束形成的ΔG°mic下降约 3kJ/mol,相当于 1个CH2 的疏水作用 ,而第 2和第 3个EO的引入使ΔG°mic下降约 2kJ/mol,即每个EO基团相当于 1/3个CH2 的疏水作用 ;说明随着分子中EO数增加 ,每个EO基团的疏水性减弱 ,亲水性的作用越来越明显 .长期被认作是亲水基团的EO也具有一定的疏水性 . 展开更多
关键词 EO SO3 胶束化 疏水性 并用 亲水基团 有机概念图 疏水作用 qspr 分子
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邻苯二甲酸酯类化合物正辛醇-水分配系数的QSPR研究 被引量:20
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作者 隆兴兴 牛军峰 史姝琼 《环境科学》 EI CAS CSCD 北大核心 2006年第11期2318-2322,共5页
采用PM3算法计算邻苯二甲酸酯类化合物(PAEs)的量子化学参数,应用偏最小二乘(PLS)算法建立了PAEs的正辛醇-水分配系数(KOW)的定量结构-性质相关(QSPR)模型.模型的结果表明,用量子化学参数建立的QSPR模型相关性显著,具有较好的稳健性和... 采用PM3算法计算邻苯二甲酸酯类化合物(PAEs)的量子化学参数,应用偏最小二乘(PLS)算法建立了PAEs的正辛醇-水分配系数(KOW)的定量结构-性质相关(QSPR)模型.模型的结果表明,用量子化学参数建立的QSPR模型相关性显著,具有较好的稳健性和预测能力,因此,利用该模型可对其他PAEs分子的lgKOW值进行初步预测.模型的结果表明,影响lgKOW的主要量子化学参数是分子总能量TE、相对分子质量Mr、平均分子极化率α和分子生成热ΔHf.lgKOW随着Mr和α的增大而增大,随着TE和ΔHf的增大而减小. 展开更多
关键词 邻苯二甲酸酯(PAEs) 定量结构-性质相关(qspr) 正辛醇-水分配系数(Kow) PM3算法 偏最小二乘(PLS)
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基于遗传-支持向量机和遗传-径向基神经网络的有机物正辛醇-水分配系数QSPR研究 被引量:13
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作者 齐珺 牛军峰 王丽莉 《环境科学》 EI CAS CSCD 北大核心 2008年第1期212-218,共7页
基于遗传算法(GA)的因子筛选和支持向量机(SVM)的非线性回归,提出了1种改进的有机物定量结构-性质相关(QSPR)建模方法——遗传-支持向量机(GA-SVM),并将其用于38种食品工业常用有机物正辛醇-水分配系数(Kow)的QSPR建模.结果显示,QSPR模... 基于遗传算法(GA)的因子筛选和支持向量机(SVM)的非线性回归,提出了1种改进的有机物定量结构-性质相关(QSPR)建模方法——遗传-支持向量机(GA-SVM),并将其用于38种食品工业常用有机物正辛醇-水分配系数(Kow)的QSPR建模.结果显示,QSPR模型选取了分子量、Hansen极性、沸点、含氧率和含氢率5种参数;模型的预测值与实测值间的误差平方和(SSE)、均方差(RMSE)和决定系数(R2)分别为0.048、0.036和0.999,表明模型具有较强的预测能力;同时,交叉验证的结果(SSE=0.295,RMSE=0.089,R2=0.995)也表明,模型具有良好的稳健性,因此,GA-SVM算法适用于对有机物正辛醇-水分配系数的QSPR建模.此外,将基于GA-SVM的QSPR模型分别与基于遗传-径向基神经网络(GA-RBFNN)和基于线性算法的模型进行了比较,结果表明,应用GA-SVM建立的QSPR模型无论从稳健性还是预测能力上都优于应用其它2种算法建立的模型,因此,GA-SVM算法比GA-RBFNN和线性算法更适合于对有机物正辛醇-水分配系数进行QSPR建模. 展开更多
关键词 定量结构-性质相关(qspr) 正辛醇-水分配系数(Kow) 遗传算法(GA) 支持向量机(SVM)
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均三硝基苯类化合物撞击感度与电性拓扑指数的QSPR研究 被引量:5
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作者 王睿 蒋军成 +1 位作者 潘勇 曹洪印 《含能材料》 EI CAS CSCD 2008年第1期90-93,共4页
采用电性拓扑态(electrotopologieal state,E-state)指数模拟分析了20种均三硝基苯类化合物的撞击感度,构建了4变量的定量结构-性质相关(QSPR)模型,其相关系数和标准偏差分别为0.929和0.079,具有较高的可靠性和相关度。模型... 采用电性拓扑态(electrotopologieal state,E-state)指数模拟分析了20种均三硝基苯类化合物的撞击感度,构建了4变量的定量结构-性质相关(QSPR)模型,其相关系数和标准偏差分别为0.929和0.079,具有较高的可靠性和相关度。模型分析表明:影响均三硝基苯类化合物撞击感度的主要因素为4个ETSI描述符对应的子结构,即saCa,-N=^ =,-CH2-和-O-。说明原子的电性状态对撞击感度有重要影响。 展开更多
关键词 有机化学 硝基化合物 撞击感度 电性拓扑态指数 定量结构-性质相关(qspr)
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用定量结构性质关系(QSPR)预测芳香系炸药的密度 被引量:3
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作者 来蔚鹏 廉鹏 +4 位作者 王伯周 贾思媛 张海昊 薛永强 庞先勇 《含能材料》 EI CAS CSCD 2007年第6期626-628,655,共4页
以物质的电子、空间等结构性质为基础,运用Gaussian98和Cerius2程序包对偶极距(Dipole)、最高占据轨道能量(EHOMO)、最低空轨道能量(ELUMO)、分子总能量(E)、旋转键(Rotlbonds)、最弱的R-NO2键长(R-NO2 bond length,R为C或N)、氢键供体(... 以物质的电子、空间等结构性质为基础,运用Gaussian98和Cerius2程序包对偶极距(Dipole)、最高占据轨道能量(EHOMO)、最低空轨道能量(ELUMO)、分子总能量(E)、旋转键(Rotlbonds)、最弱的R-NO2键长(R-NO2 bond length,R为C或N)、氢键供体(Hbond donor)和中点势(Vmid)8种描述符进行了计算,采用Cerius2程序包中的QSPR方法建立了芳香系炸药密度与8种描述符之间的构效关系式,相关系数R为0.909,30个化合物所构成的训练集和15个化合物所构成的预测集预测密度与实测密度之间的平均误差分别为3.33%和2.94%。 展开更多
关键词 物理化学 芳香炸药 密度 qspr
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