title: QSPRs for the prediction of photodegradation half-life of PCBs in n-hexane.
abstract: By partial least squares (PLS) regression analysis, a quantitative structure-property relationship (QSPR) model was developed for photodegradation half-life (t1/2) of polychlorinated biphenyls (PCBs) in n-hexane solution under UV irradiation. Quantum chemical descriptors computed by PM3 Hamiltonian were used as predictor variables. The cross-validated value for the optimal QSPR model was 0.589, indicating good predictive capability for log t1/2 values of PCBs in n-hexane. The QSPR results show that standard heat of formation (DeltaHf), total energy (TE), and molecular weight (Mw) have dominant effect on t1/2 values of PCBs in n-hexane. Increasing DeltaHf and TE values or decreasing Mw values of the PCBs leads to decrease of log t1/2 values. In addition, increasing the largest negative atomic charge on a carbon atom and dipole moment of the PCBs leads to decrease of log t1/2 values.
authors.affiliation: State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875, P. R. China. niujunfeng@tsinghua.org.cn
authors.forename: J F
authors.initials: JF
authors.lastname: Niu
authors.forename: Z F
authors.initials: ZF
authors.lastname: Yang
authors.forename: Z Y
authors.initials: ZY
authors.lastname: Shen
authors.forename: L L
authors.initials: LL
authors.lastname: Wang
mesh_terms: D004785:Environmental Pollutants / Q000528:radiation effects; D006207:Half-Life; D006586:Hexanes / Q000737:chemistry; D016018:Least-Squares Analysis; D008956:Models, Chemical; D010782:Photolysis; D011078:Polychlorinated Biphenyls / Q000737:chemistry / Q000528:radiation effects*; D021281:Quantitative Structure-Activity Relationship; D015203:Reproducibility of Results; D014466:Ultraviolet Rays
chemical_list: D004785:Environmental Pollutants; D006586:Hexanes; C026385:n-hexane; D011078:Polychlorinated Biphenyls