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王连生, Xiaodong Wang a, Songlin Tang b, Shushen Liu a, Shihai Cui a, Liansheng Wang a, *
Chemosphere 51(2003)617-632,-0001,():
-1年11月30日
Polychlorinated biphenyls (PCBs) congeners with various degrees of chlorination and substitution patterns are among the most widespread and persistent man-made organic pollutants. They are toxic, lipophilic and tend to be bioaccumulated. The knowledge of the physico-chemical properties is very useful to explain the environmental behavior of PCBs and to perform an exposure assessment. In this paper, we have used a new molecular representation, the molecular hologram, to generate quantitative structure-property relationship models to predict the physico-chemical properties of biphenyl and all of its chlorinated congeners. The investigated properties include 1-octanol/water partition coefficient (log Kow), aqueous solubility (log Sw), aqueous activity coefficient (log Yw), Total molecular surface area, Henry s law constant (logH). The results show that this new quantitative structure-activity relationship approach presents highly predictive models for important physico-chemical properties of PCBs.
Polychlorinated biphenyls, Holographic quantitative structure-activity relationship, Quantitative structure-property relationship, Physico-chemical properties, Molecular hologram
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王连生, Gehui Wang, Sulian Niu, Caie Liu, Liansheng Wang*
Atmospheric Environment 36(2002)1941-1950,-0001,():
-1年11月30日
In this study aerosol samples of PM10 and PM2.5 collected from 18 February 2001 to 1 May 2001 in Nanjing, China were analyzed for their water-soluble organic compounds. A series of homologous dicarboxylic acids (C2-10) and two kinds of aldehydes (methylglyoxal and 2-oxo-malonaldehyde) were detected by GC and GC/MS. Among the identified compounds, the concentration of oxalic acid was the highest at all the five sites, which ranged from 178 to 1423 ng/m3. The second highest concentration of dicarboxylic acids were malonic and succinic acids, which ranged from 26.9 to 243 ng/m3. Higher level of azelaic acid was also observed, of which the maximum was 301 ng/m3. As the highest fraction of dicarboxylic acids, oxalic acid comprised from 28% to 86% of total dicarboxylic acids in PM10 and from 41% to 65% of total dicarboxylic acids in PM2.5. The dicarboxylic acids (C2, C3, C4) together accounted for 38-95% of total dicarboxylic acids in PM10 and 59-87% of dicarboxylic acids in PM2.5. In this study, the total dicarboxylic acids accounted for 2.8-7.9% of total organic carbon (TOC) of water-soluble matters for PM10 and 3.4-11.8% of TOC for PM2.5. All dicarboxylic acids detected in this study together accounted for about+N35 1% of particle mass. The concentration of azelaic acid was higher at one site than others, which may be resulted from higher level of volatile fat used for cooking. The amounts of dicarboxyic acids (C2,3,4,9) and 2-oxo-malonaldehyde of PM2.5 were higher in winter and lower in spring. Compared with other major metropolitans in the world, the level of oxalic acid concentration of Nanjing is much higher, which may be contributed to higher level of particle loadings, especially for fine particles.
Dicarboxylic acid, Aldehyde, Atmospheric aerosol, Spatial and temporal variations
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【期刊论文】HYDROLYSIS KINETICS OF PHENYLSULFONYL-CYCLOALKANE CARBOXYLATES
王连生, Han Shuokui*, Zhang Huichun, Zhang Aiqian, Wang Liansheng
Chemosphere, Vol. 31, No.6, pp. 3425-3431, 1995,-0001,():
-1年11月30日
Batch data for hydrolysis of phenylsulfonyl-eycloalkane carboxylates have been measured at a specific pH at various temperatures. A set of regression equations between hydrolysis rate constants and temperatures was established. Effects of various chemical groups of the tested compounds on hydrolytic reactions were compared.
phenylsulfonyl-cycloalkane carboxylates,, hydrolysis kinetics
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王连生, Zhifen Lin, *, †, ‡, § Kedong Yin, † Ping Shi, † Liansheng Wang, ‡ and Hongxia Yu‡
Chem. Res. Toxicol. 2003, 16, 1365-1371,-0001,():
-1年11月30日
Quantitative structure-activity relationship (QSAR) approaches are proposed in this study to predict the joint effects of mixture toxicity. The initial investigation studies the joint effects between cyanogenic toxicants and aldehydes to Photobacterium phosphoreum. Joint effects are found to result from the formation of a carbanion intermediate produced through the chemical interactions between cyanogenic toxicants and aldehydes. Further research indicates that the formation of carbanion intermediate is highly correlated with not only the charge of the carbon atom in the-CHO of aldehydes but also the charge of the carbon atom (C*) in the carbochain of cyanogenic toxicants. The charge of the carbon atom in the-CHO of aldehydes is quantified by using the Hammett constant (
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王连生, Shu-Shen Liu, * Chun-Sheng Yin, and Lian-Sheng Wang
J. Chem. Inf. Comput. Sci. 2002, 42, 749-756,-0001,():
-1年11月30日
The MEDV-13, molecular electronegativity distance vector based on 13 atomic types, has at best 91 descriptors. It is impossible to indirectly use multiple linear regression (MLR) to derive a quantitative structure-activity relationship (QSAR) model. Although principal component regression (PCR) or partial least-squares regression (PLSR) can be employed to develop a latent QSAR model, it is still difficult how to determine the principal components (PCs) and depict the physical meaning of the PCs. So, a genetic algorithm (GA) is first employed to select an optimal subset of the descriptors from original MEDV-13 descriptor set. Then MLR is utilized to build a QSAR model between the optimal subset and the biological activities of three sets of compounds. For 31 benchmark steroids, a 5-descriptor QSAR model (M1) between the corticosteroid-binding globulin (CBG) binding affinity of the steroids and 5-descriptor subset is developed. The root-mean-square error of estimations (RMSEE) and the correlation coefficient of estimations (r) between the CBG binding affinity (BA) observed and the BA estimated by M1 are 0.422 and 0.9182, respectively. The root-mean-square error of predictions (RMSEP) and the correlation coefficient of predictions (q) between the BA observed and the BA predicted by leave-one-out cross validations are 0.504 and 0.8818, respectively. For 58 dipeptides inhibiting angiotensin-converting enzyme (ACE), a 5-variable QSAR model (M2) between the pIC50 of peptides and 5-descriptor subset is derived. The M2 has a high quality with RMSEE) 0.339 and r) 0.9398 and RMSEP) 0.370 and q) 0.9280. For 16 indomethacin amides and esters (ImAE) inhibiting cyclooxygenase-2 (COX-2), a 6-variable QSAR model (M3) with RMSEE) 0.079 and r) 0.9839 and RMSEP) 0.151 and q) 0.9413 is built.
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