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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

SYNERGISTIC INTERACTIONS ON PHENOL ADSORPTION FROM AQUEOUS SOLUTIONS BY POLYMERIC ADSORBENTS

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Chinese Journal of Polymer Science 2005年第4期23卷 441-447页

作者：陈金龙 StateKeyLaboratoryofPollutionControlandResourcesReuse SchooloftheEnvironmentNanjingUniversityNanjing210093China

In this paper,the adsorption behaviors of phenol on polymeric adsorbents(Amberlite XAD4,NDA101,and D301) were investigated in batch system at 293,303,and 313 K,*** the results shown,the adsorption isotherms of phenol on all adsorbents can be well fitted by Langmuir and Freundlich equations,which indicate a favorable and exothermic *** adsorption capacity on a newly developed aminated adsorbent,NDA101,on which adsorption could be achieved by both hydrogen bonding interaction and π-π interaction,are higher than that on a weak base adsorbent,D301,on which adsorption could be achieved by hydrogen bonding interaction only,and on a nonpolar adsorbent,XAD4,on which adsorption could be achieved by π-π interaction *** results of this paper indicate that the synergistic effect of some weak interactions,which occur simultaneously would contribute more to the adsorption than that occur individually.

关键词： Polymeric adsorbent Phenol Adsorption behaviours Synergistic interaction

Competitive and cooperative adsorption behaviors of phenol and aniline onto nonpolar macroreticular adsorbents

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Journal of Environmental Sciences 2005年第4期17卷 529-534页

作者： ZHANGWei-ming CHENJin-long PANBing-cai ZHANGQuan-xing StateKeyLaboratoryofPollutionControlandResourcesReuse SchooloftheEnvironmentNanjingUniversityNanjing210093China

The adsorption behaviors of phenol and aniline on nonpolar macroreticular adsorbents(NDA100 and Amberlite XAD4) were investigated in single or binary batch system at 293K and 313K respectively in this study. The results indicated that the adsorption isotherms of phenol and aniline on both adsorbents in both systems fitted well Langmuir equation, which indicated a favourable and exothermic process. At the lower equilibrium concentrations, the individual amount adsorbed of phenol or aniline on macroreticular adsorbents in single-component systems was higher than those in binary-component systems because of the competition between phenol and aniline towards the adsorption sites. It is noteworthy, on the contrast, that at higher concentrations, the total uptake amounts of phenol and aniline in binary-component systems were obviously larger than that in single-component systems, and a large excess was noted on the adsorbent surface at saturation, which is presumably due to the cooperative effect primarily arisen from the hydrogen bonding or weak acid-base interaction between phenol and aniline.

关键词： macroreticular adsorbent phenol aniline competitive adsorption cooperative adsorption

ADSORPTION OF 2,4-D ON MODIFIED HYPERCROSSLINKED POLYSTYRENE(NDA-99)AND XAD-4 RESIN

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Chinese Journal of Polymer Science 2005年第4期23卷 435-440页

作者：邱宇平 StateKeyLaboratoryofPollutionControlandResourcesReuse SchooloftheEnvironmentNanjingUniversityNanjing210093China

The adsorption behavior of pesticide 2,4-dichlorophenoxyacetic acid(2,4-D)in aqueous solution has been investigated using a hypercrosslinked polystyrene adsorbent(NDA-99)modified by dimethylamine group as well as a nonionic macroporous adsorbent(XAD-4).The Langmuir and Freundlich isotherm models were employed to fit the experimental data to describe adsorption *** shows that NDA-99 resin exhibits an adsorption affinity for 2,4-D higher than XAD-4 resin owing to its exceptional micropore structure and the amine group of the hypercrosslinked matrix. Further studies indicate that the hydrogen bonding interaction and the stronger π-π conjugation play a significant role in the course of the adsorption of 2,4-D on NDA-99 resin,which is in agreement with the IR spectroscopic results and the ΔE values of HOMO(the highest occupied molecular orbit)of adsorbent and LUMO(the lowest unoccupied molecular orbit)of adsorbate calculated from the MINDO/3 model.

关键词： 2,4-D Adsorption Hypercrosslinked resin Microporous structure Hydrogen bonding

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

SINGLE AND BINARY ADSORPTION PERFORMANCE OF SALICYLIC ACID AND 5-SULFOSALICYLIC ACID ONTO HYPERCROSSLINKED POLYMERIC ADSORBENTS

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Chinese Journal of Polymer Science 2005年第4期23卷 373-378页

作者：刘福强 StateKeyLaboratoryofPollutionControlandResourceReuse SchooloftheEnvironmentNanjingUniversityNanjing210093China

Single and binary adsorption behaviors of salicylic acid and 5-sulfosalicylic acid onto hypercrosslinked polymeric adsorbents,***-101 and NDA-99 were *** Freundlich model can successfully describe all the adsorption isotherms tested,which indicates a favorable and exothermic adsorption *** adsorption of salicylic acid relies on π-π interaction,while the electrostatic interaction further influences the adsorption of 5-sulfosalicylic acid onto *** adsorptive capacity of salicylic acid on NDA-99 decreases but increases on NDA-101 with 5-sulfosalicylic acid as the background component in a binary solute *** amount of 5-sulfosalicylic acid adsorbed was decreased with the increase in initial concentration of salicylic acid on both *** competition for the adsorption sites is considered to be predominant in the solid-to-liquid interaction *** adsorption selectivity of salicylic acid onto NDA-101 is higher than onto NDA-99 by more than an order of ***,combination technique involving NDA-101 followed by NDA-99 can be effectively applied to separate and recover salicylic acid and 5-sulfosalicylic acid from wastewater.

关键词： Binary competitive adsorption Hypercrosslinked polymeric adsorbent Salicylic acid 5-Sulfosalicylic acid

Prediction of the Aqueous Solubilities of Polychlorinated Biphenyls

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Chinese Chemical Letters 2004年第4期15卷 467-470页

作者： ShuShenLIU ShiHaiCUI LianShengWANG StateKeyLaboratoryofPollutionControlandResourcesReuse SchooloftheEnvironmentNanjingUniversityNanjing210093

Using the molecular electronegativity distance vector descriptors derived directly from the molecular topological structures, the aqueous solubilities of polychlorinated biphenyls (PCBs) were predicted. A three-variable regression equation with correlation coefficient of 0.9739 and the root mean square errors of 0.26 was developed. The descriptors included in the equation represent three interactions between three pairs of atomic types, i.e., atom -C= and >C=, -C= and -Cl, and -Cl and -Cl. It has been proved that the aqueous solubilities of 137 PCB congeners can be accurately predicted as long as there are more than 65 calibration compounds.

关键词： Polychlorinated biphenyls (PCBs) aqueous solubility molecular electronegativity distance vector (MEDV).

Binary competitive adsorption of naphthalene compounds onto an aminated hypercrosslinked macroporous polymeric adsorbent

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Journal of Environmental Sciences 2004年第3期16卷 471-475页

作者： LIUFu-qiang CHENJin-long CHENGXiu-mei GEJun-jie LIAi-min ZHANGQuan-xing StateKeyLaboratoryofPollutionControlandResourcesReuse SchooloftheEnvironmentNanjingUniversityNanjing210093China

An aminated hypercrosslinked macroporous polymeric adsorbent was synthesized and characterized. Adsorption isotherms for 1 amino 2 naphthol 4 sulfonic acid(1, 2, 4 acid) and 2 naphthol obtained from various binary adsorption environments can be well fitted by Freundlich equation, which indicated a favorable adsorption process in the studied range. Adsorption for 1, 2, 4 acid was an endothermic process in comparison with that for 2 naphthol of an exothermic process. 2 naphthol molecules put a little influence on the adsorption capacity for 1, 2, 4 acid. However, the adsorption to 1, 2, 4 acid depressed that to 2 naphthol in a large extent for the stronger electrostatic interaction between 1, 2, 4 acid and adsorbent. The predominant mechanism can be contributed to the competition for adsorption sites. And the simultaneous environment was confirmed to be helpful to the selective adsorption towards 1,2,4 acid based on the larger selectivity index.

关键词： aminated hypercrosslinked macroporous polymeric adsorbent 1, 2, 4 acid 2 naphthol competitive adsorption

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)