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Chinese Journal of Structural Chemistry 2005年第7期24卷 851-857,740页

作者： WANGZun-Yao HANXiang-Yun wanglian-sheng SchooloftheEnvironment NanjingUniversityJiangsu210093China／／SchoolofChemicalandBiologicalEngineeringYanchengInstituteofTechnologyJiangsu224003China SchooloftheEnvironment NanjingUniversityJiangsu210093China SchoolofChemicalandBiologicalEngineering YanchengInstituteofTechnologyJiangsu224003China

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.

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)

Immobilization study of biosorption of heavy metal ions onto activated sludge

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Journal of Environmental Sciences 2004年第4期16卷 640-645页

作者： WUHai-suo ZHANGAi-qiang wanglian-sheng StateKeyLaboratoryofPollutionControlandResourcesReuse SchooloftheEnvironmentNanjingUniversityNanjing210093China

Activated sludge was immobilized into Ca-alginate beads via entrapment, and biosorption of three heavy metal ions, copper(Ⅱ), zinc(Ⅱ), and chromimum(Ⅱ), from aqueous solution in the concentration range of 10\_100 mg/L was studied by using both entrapped activated sludge and inactivated free biomass at pH≤5. A biphasic metal adsorption pattern was observed in all immobilized biomass experiments. The biosorption of metal ions by the biosorbents increased with the initial concentration increased in the medium. The adsorption rate of immobilized pre-treated activated sludge(PAS) was much lower than that of free PAS due to the increase in mass transfer resistance resulting from the polymeric matrix. Biosorption equilibrium of beads was established in about 20 h and the adsorbed heavy metal ions did not change further with time. No significant effect of temperature was observed in the test for free biomass while immobilized PAS appeared to be strong temperature dependent in the test range of 10 and 40℃. Besides, the content of activated sludge in the calcium alginate bead has an influence on the uptake of heavy metals. The sorption equilibrium was well modeled by Langmuir isotherm, implying monomolecular adsorption mechanism. Carboxyl group in cell wall played an important role in surface adsorption of heavy metal ions on PAS.

关键词： biosorption alginate beads immobilization heavy metal activated sludge wastewater treatment

Quantitative structure-property relationship of aromatic sulfur-containing carboxylates

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Journal of Environmental Sciences 2003年第6期15卷 721-727页

作者： LIUXin-hui YANGZhi-feng wanglian-sheng StateKeyLaboratoryofEnvironmentalSimulationandPollutionControl InstituteofEnvironmentalSciencesBeijingNormalUniversityBeijing100875China. SchooloftheEnvironment NanjingUniversityNanjing210093China

Based on quantum chemical calculations, TLSER model(theoretical linear solvation energy relationships) and atomic charge approach were applied to model the partition properties(water solubility and octanol/water partition coefficient) of 96 aromatic sulfur-containing carboxylates, including phenylthio, phenylsulfinyl and phenylsulfonyl carboxylates. In comparison with TLSER models, the atomic charge models are more accurate and reliable to predict the partition properties of the kind of compounds. For the atomic charge models, the molecular descriptors are molecular surface area(S), molecular shape(O), weight(M W), net charges on carboxyl group(Q OC), net charges of nitrogen atoms(Q N), and the most negative atomic charge(q -) of the solute molecule. For water solubility(log S W) and octanol/water partition coefficient(log K OW), the correction coefficients r 2 adj(adjusted for degrees of freedom) are 0.936 and 0.938, and the standard deviations are 0.364 and 0.223, respectively.

关键词： octanol/water partition coefficient water solubility atomic charge model TLSER quantum chemical descriptor

Determination of hydroxyl radicals with salicylic acid in aqueous nitrate and nitrite solutions

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Journal of Environmental Sciences 2004年第4期16卷 687-689页

作者： YANGXi ZHANMan-jun KONGLing-ren wanglian-sheng StateKeyLaboratoryofPollutionControlandResourceReuse SchooloftheEnvironmentNanjingUniversityNanjing210093China

The qualitative and quantitative analyses of reactive oxygen species are essential to determine their steady-state concentration and related reaction mechanisms in environmental aquatic systems. In this study, salicylic acid was employed as an innovative molecular probe of hydroxyl radical(OH) generated in aqueous nitrate and nitrite solutions through photochemical reactions. Kinetic studies showed that the steady-state concentrations of OH in aqueous NO- 3(10 mmol/L, pH=5) and NO- 2(10 mmol/L, pH=5) solutions under ultraviolet irradiation were at a same magnitude, 10 -15 mol/L. Apparent quantum yields of OH at 313 nm were measured as 0.011 and 0.07 for NO- 3 and NO- 2 respectively, all comparable to the results of previous studies.

关键词： photochemistry hydroxyl radical salicylic acid nitrate nitrite

Holographic quantitative structure-activity relationship for prediction acute toxicity of benzene derivatives to the guppy(poecilia reticulata)

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Journal of Environmental Sciences 2004年第3期16卷 423-427页

作者： HUANGHong WANGXiao-dong DAIXuan-li YUYa-juan wanglian-sheng StateKeyLaboratoryofPollutionControlandResourcesReuse.SchooloftheEnvironment NanjingUniversityNanjing210093China

Holographic quantitative structure activity relationship(HQSAR) is an emerging QSAR technique with the combined application of molecular hologram, which encoded the frequency of occurrence of various molecular fragment types, and the subsequent partial least squares(PLS) regression analysis. In this paper, the acute toxicity data to the guppy( poecilia reticulata) for a series of 56 substituted benzenes, phenols, aromatic amines and nitro aromatics were subjected and this resulted in a model with a high predictive ability. The influence of fragment size and fragment distinction parameters on the quality of HQSAR model was investigated. The robustness and predictive ability of the model were also validated by leave one out (LOO) cross validation procedure and external testing data set.

关键词： benzene derivatives HQSAR molecular hologram acute toxicity guppy (poecilia reticulata)

Surface microlayer enrichment of volatile organic compounds and semi-volatile organic compounds in drinking water source

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Journal of Environmental Sciences 2004年第1期16卷 56-60页

作者： HUANGZhi ZHOUWen YUYa-juan ZHANGAi-qian HANShuo-kui wanglian-sheng StateKeyLaboratoryofPollutionControlandSourcesReuse SchooloftheEnvironmentNanjingUniversityNanjing210093China

Enrichment of volatile organic compounds(VOC) and semi-volatility organic compounds(SVOC) in surface microlayer(SM) of three drinking water sources were studied. The enrichment factor( EF s) were 0.67 to 13.37 and 0.16 to 136, respectively. The results showed some VOC and most SVOC could enrich in SM. Some EF s of SVOC was quite high. Suspension and temperature could affect EF s of SVOC, slim wind and water movement do not destroy enrichment of organic in SM.

关键词： surface microlayer enrichment GC-MS SPE