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Francisco Torrens Gloria Castellano 《Journal of environmental science and health. Part. B》2013,48(6):400-407
The high‐performance liquid‐chromatographic retentions of red‐wine pesticide residues are modeled by structure–property relationships. The effect of different types of features is analyzed: geometric, lipophilic, etc. The properties are fractal dimensions, partition coefficient, etc., in linear and nonlinear correlation models. Biological plastic evolution is an evolutionary perspective conjugating the effect of acquired characters and relations that emerge among the principles of evolutionary indeterminacy, morphological determination and natural selection. It is applied to design the co‐ordination index that is used to characterize pesticide retentions. The parameters used to calculate the co‐ordination index are the molar formation enthalpy, molecular weight and surface area. The morphological and co‐ordination indices barely improve the correlations. The fractal dimension averaged for non?buried atoms, partition coefficient, etc. distinguishes the pesticide molecular structures. The structural and constituent classification is based on nonplanarity, and the number of cycles, and O, S, N and Cl atoms. Different behavior depends on the number of cycles. 相似文献
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本文采用摇瓶法测定了14各甲酰苯胺类化合物的溶解度及正辛醇/水分配系数,二者之间具有较好的相关性,应用线性溶剂化相关方法获得的相关方程,能更好地预测测苯甲酰苯胺类化合物的的水溶解度和正辛醇/水分配系数。 相似文献
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DUAN Jinming 《环境科学学报(英文版)》2009,21(1):30-34
Colloidal particle stability and some other interfacial phenomena are governed by interfacial force interactions. The two well known
forces are van der Waals force and electrostatic force, as documented by the classical Derjaguin, Landau, Verwey, and Overbeek
(DLVO) theory. Moreover, advances in modern instrumentation and colloid science suggested that some short-ranged forces or structure
forces are important for relevant colloidal systems. The interfacial and/or molecular forces can be measured as a resultant force as
function of separation distance by atomic force microscopy (AFM) colloid probe. This article presents a discussion on AFM colloid
probe measurement of silica particle and silica wafer surfaces in solutions with some technical notifications in measurement and data
convolution mechanisms. The measured forces are then analyzed and discussed based on the ‘constant charge’ and ‘constant potential’
models of DLVO theory. The di erence between the prediction of DLVO theory and the measured results indicates that there is a strong
short-range structure force between the two hydrophilic surfaces, even at extremely low ionic concentration, such as Milli-Q water
purity solution. 相似文献
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有机污染物在被动采样材料与环境介质之间的平衡分配系数(K_P),是测定环境中有机污染物浓度的重要参数,但K_P值大部分都需要经过繁琐的实验测定获取,无法逐个测定数量繁多的污染物,因此需开发一种预测K_P值的方法。为此,搜集整理了一些多环芳香烃(PAHs)和多氯联苯(PCBs)的低密度聚乙烯(LDPE)-空气分配系数(K_PA)的实测值,基于理论线性溶解能(TLSER)和定量结构性质关系(QSPR),利用逐步多元线性回归(MLR)分别构建了预测K_PA值的模型。模型的决定系数R2adj分别为0.927和0.956,交叉验证系数Q2LOO分别为0.915和0.946,外部系数Q2ext分别为0.913和0.960。结果表明,2种模型具有良好的拟合优度、稳健性和预测能力,并解释了模型的机理。所构建的2种模型均可用来预测应用域内有机污染物的LDPE膜-空气分配系数。 相似文献
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在B3LYP/6-31G水平上全优化计算了多氯代二苯并—对-二英和多氯代二苯并呋喃(PCDD/Fs)系列物的分子结构;基于得到的分子结构描述符,依据修正的线性溶解能理论,分别建立了PCDDs和PCDFs的正辛醇/水分配系数的定量结构-性质关系模型(R2分别为0.985和0.966),并用交叉验证法对模型进行了验证(q2分别为0.983和0.936),用t-检验对各变量进行了检验.检验结果表明,模型的预测能力优于AM1法、单苯环氯取代指数法和拓扑量子方法得出的模型. 相似文献
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以单壁碳纳米管(SWCNTs)为固定相,采用高压匀浆法,制备HPLC色谱柱.测定乙腈相中18种有机化合物在SWCNTs色谱柱上的保留因子,研究SWCNTs与化合物的相互作用.结果表明,有机化合物取代基的种类和个数、杂原子的个数影响乙腈相中有机化合物与SWCNTs的相互作用.采用线性溶解能关系(LSER)定量表征SWCNTs与有机化合物的相互作用,所构建的LSER模型具有较强的拟合能力(R2=0.844)和稳健性(Q2LOO=0.768),发现π-/n-电子对作用和空穴/弥散作用是控制SWCNTs与有机化合物相互作用的主要因素. 相似文献
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IntroductionThephysicochemicalprofileoforganiccompoundslargelydeterminestheirdistributionbetweenenvironmentalmedia .Fortheenvironmentalbehavioroforganiccontaminants,theoctanol waterpartitioncoefficient(KOW)ismoresignificant.KOWhasbeenwidelyrelatedtobioc… 相似文献
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