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science china chemistry 2010年第4期53卷 820-825页

作者： LI YanRong, GAN ZhiYong, LI YanFen, Liu Qian, BAO JianChun, DAI ZhiHui & HAN Min Jiangsu Key Laboratory of Biofunctional Materials college of chemistry and environmental science, nanjing normal university, nanjing 210097, china 1. Jiangsu Key Laboratory of Biofunctional Materials Nanjing Normal University Nanjing 210097 China2. College of Chemistry and Environmental Science Nanjing Normal University Nanjing 210097 China

This paper reports a simple method for immobilization of acetylcholinesterase (AChE) on one-dimensional (1D) gold (Au) nanoparticles for detection of organophosphorous (OP) insecticides. 1D Au nanoparticles were prepared by electrodeposition in the pores of an alumina template which was subsequently removed by 2.0 M NaOH solution. They were characterized by XRD and FESEM. The immobilized AChE retained its biological activity and catalyzed the hydrolysis of acetylthiocholine to form thiocholine, which was subsequently oxidized to produce detectable signals. Based on the inhibition toward the enzymatic activity of AChE by OP insecticides, sensitive detection of methamidophos (an OP insecticide) was performed. Under optimal conditions, the sensors could be used for the determination of methamidophos ranging from 0.004 to 24 μg/mL with the detection limit of 0.001 μg/mL. The developed OP insecticide biosensors exhibited satisfactory stability and reproducibility. This work demonstrated that 1D Au nanoparticles could serve as an ideal carrier for immobilization of AChE to fabricate the corresponding biosensor.

关键词： acetylcholinesterase organophosphorous insecticides immobilization gold

Bacterial Communities in a Buried Ancient Paddy Soil from the Neolithic Age

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Pedosphere 2010年第3期20卷 389-398页

作者： SHEN Wei-Shou YIN Rui LIN Xian-Gui CAO Zhi-Hong State Key Laboratory of Soil and Sustainable Agriculture Institute of Soil Science Chinese Academy of SciencesNanjing 210008 (China) college of chemistry and environmental science Nanjing Normal University Nanjing 210097 (China) Joint Open Laboratory of Soil and Environment Institute of Soil Science Chinese Academy of Sciences and Hong KongBaptist University Nanjing 210008 (China)

An ancient irrigated paddy soil from the Neolithic age was excavated at Chuodunshan Site in the Yangtze River Delta, close to Suzhou, china. The soil organic matter (SOM) content in the prehistoric rice soil is comparable to the average SOM content of present rice soils in this region, but it is about 5 times higher than that in the parent materials. As possible biomarkers to indicate the presence of the prehistoric paddy soil, the bacterial communities were investigated using the techniques of aerobic and anaerobic oligotrophic bacteria enumeration, Biolog analysis, and polymerase chain reaction-denaturing gradient gel electrophoresis (PCR-DGGE). The results showed that in the buried soil layers, the prehistoric paddy soil had the largest number of aerobic and anaerobic oligotrophic bacteria, up to 6.12 and 5.86 log cfu g-1 dry soil, respectively. The prehistoric paddy soil displayed better carbon utilization potential and higher functional diversity compared to the parent materials and a prehistoric loess layer. The Shannon index and richness based on DGGE profiles of bacterial 16S rRNA genes were higher in prehistoric paddy soil than those in the prehistoric loess soil. It might be concluded that the prehistoric irrigated rice cultivation accumulated the SOM in plowed soil layer, and thus increased soil bacterial populations, metabolic activity, functional diversity and genetic diversity. Bacterial communities might be considered as the sensitive indicators of the presence of the prehistoric paddy soil in china's Yangtze River Delta.

关键词： biomarker denaturing gradient gel electrophoresis oligotrophic bacteria paleosols prehistoric paddy soil

新型溶胶-凝胶气相色谱柱:聚甲基苯基硅氧烷柱、Carbowax柱及PEG-Silane柱

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分析测试学报 2004年第4期23卷 5-8页

作者：王东新南京师范大学化学与环境科学学院江苏南京210097

采用聚甲基苯基硅氧烷、Carbowax20M、PEG-silane为固定相制取了溶胶-凝胶气相色谱毛细管柱。在这些色谱柱上脂肪酸、酚类、胺和苯胺类、醇、醛等各类化合物都得到很好的分离。采用这些固定相的溶胶-凝胶柱对化合物的分离也表现出很好... 详细信息

采用聚甲基苯基硅氧烷、Carbowax20M、PEG-silane为固定相制取了溶胶-凝胶气相色谱毛细管柱。在这些色谱柱上脂肪酸、酚类、胺和苯胺类、醇、醛等各类化合物都得到很好的分离。采用这些固定相的溶胶-凝胶柱对化合物的分离也表现出很好的重现性。溶胶-凝胶法制柱对各类固定相是普遍适用的方法。

关键词：气相色谱溶胶-凝胶聚甲基苯基硅氧烷 Carbowax PEG-silane 色谱柱

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污染生态学领域的稀土应用研究进展

中国稀土学报 2004年第2期22卷 177-182页

作者：周青黄晓华张光生梁婵娟曾庆玲江南大学工业生物技术教育部重点实验室江苏无锡214036 南京师范大学化学与环境科学学院

综述了近年来应用稀土诱导植物抗性,继而减轻酸雨、臭氧、紫外辐射、农药、重金属等环境污染伤害植物的研究进展,提出稀土诱导植物抗性、减轻环境污染胁迫伤害的机理在于调控植物细胞内生化代谢网络,维持植物自由基防御系统,光合作用、... 详细信息

综述了近年来应用稀土诱导植物抗性,继而减轻酸雨、臭氧、紫外辐射、农药、重金属等环境污染伤害植物的研究进展,提出稀土诱导植物抗性、减轻环境污染胁迫伤害的机理在于调控植物细胞内生化代谢网络,维持植物自由基防御系统,光合作用、细胞膜系统、矿质营养代谢等正常生理功能,增强植物对环境污染的耐受幅度,在此基础上分析了目前研究中存在的主要问题。

关键词：污染生态学稀土诱导抗性抗污染能力植物作用机理

Landscape structure and land uese on county level in northeastern Yunnan Province of china——a case study of Huize County

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Journal of environmental sciences 2000年第3期12卷 355-360页

作者： WANG Jin\|liang, NI Shao\|xiang (college of Geographical science, nanjing normal university, nanjing 210097, china) 南京师范大学江苏南京 2 1 0 0 97

Taking Huize County as an example, the paper analyzed the landscape structure(landscape element structure, landscape type structure, landscape spatial structure, landscape succession structure) and the relations between landscape structure and land use. It was pointed out that the agriculture should be developed in harmony with the landscape structure in the study area.

关键词： landscape structure land use agriculture Yunnan Province china

Predicting bioconcentration factor values of organic pollutants based on medv descriptors derived QSARs

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science china chemistry 2007年第5期50卷 587-592页

作者： CUI ShiHai1,2, YANG Jing1, LIU ShuShen2,3 & WANG LianSheng2 1 college of chemistry and Environment, nanjing normal university, nanjing 210097, china 2 State Key Laboratory of Pollution Control and Resources Reuse, School of the Environment, nanjing university, nanjing 210093, china 3 Key Laboratory of Yangtze Aquatic Environment, Ministry of Education, college of environmental science and Engineering, Tongji university, Shanghai 200092, china 1. college of chemistry and Environment Nanjing Normal University Nanjing 210097 China 2. State Key Laboratory of Pollution Control and Resources Reuse School of the Environment Nanjing University Nanjing 210093 China 3. Key Laboratory of Yangtze Aquatic Environment Ministry of Education College of Environmental Science and Engineering Tongji University Shanghai 200092 China

The molecular electronegativity-distance vector (MEDV) is employed todescribe the chemical structure of organic *** linear relationships between themolecular descriptors and BCF values are developed by best subset regression and partial leastsquare regression *** main structural factors influencing the bioactivities are -CH2,-X,-Cnot <,- C not <,-O-.The high values of r2 and q2_(LOO) present good estimation ability and stabilityof *** prediction power for external samples is validated by the model developed from thetraining set.

关键词： POPs, BCF, MEDV, QSAR

Effect of climatic change on snowmelt runoffs in mountainous regions of inland rivers in Northwestern china

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science china Earth sciences 2006年第8期49卷 881-888页

作者： WANG Jian1 & LI Shuo2 1. Cold and Arid Regions environmental and Engineering Research Institute, Chinese Academy of sciences, Lanzhou 730000, china 2. college of Geography, nanjing normal university, nanjing 210097, china 1. Cold and Arid Regions environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China 2. college of Geography Nanjing Normal University Nanjing 210097 China

Climatic change has significant impacts on snow cover in mid-latitude mountainous re- gions, in the meantime, spatial and temporal changes of snow cover and snowmelt runoffs are con- sidered as sensitive indicators for climatic change. In this study, the upper Heihe Watershed in the Qilian Mountains was selected as a typical area affected by snow cover and snowmelt runoffs in northwestern china. The changes in air temperatures, precipitation, snowfall and spring snowmelt runoffs were analyzed for the period from 1956 to 2001. The results indicate that climatic warming was apparent, particularly in January and February, but precipitation just fluctuated without a clear trend. The possible changes of snowmelt runoffs in the upper Heihe watershed in response to a warming of 4℃ were simulated using Snowmelt Runoff Model (SRM) based on the degree-day factor algorithm. The results of the simulation indicate that a forward shifting of snow melting season, an increase in water flows in earlier melting season, and a decline in flows in later melting season would occur under a 4℃ warming scenario.

关键词： climatic changes, snowmelt runoff, SRM model, upper Heihe Watershed, simulating.

Miocene Bahean stratigraphy in the Longzhong Basin, northern central china and its implications in environmental change

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science china Earth sciences 2006年第12期49卷 1270-1279页

作者： LI Jijun1,2, ZHANG Jun1, SONG Chunhui1, ZHAO Zhijun2, ZHANG Yong1, WANG Xiuxi 1, ZHANG Jianming1 & CUI Qiaoyu1 1. Key Laboratory of Western china’s environmental Systems (Ministry of Education) & college of Earth and Environment sciences, Lanzhou university, Lanzhou 730000, china 2. Jiangsu Key Laboratory of environmental Change and Ecological Construction & college of Geography, nanjing normal university, nanjing 210097, china 1. Key Laboratory of Western china’s environmental Systems (Ministry of Education) & college of Earth and Environment sciences Lanzhou University Lanzhou 730000 China 2. Jiangsu Key Laboratory of environmental Change and Ecological Construction & college of Geography Nanjing Normal University Nanjing 210097 China

Fossil mammal-riched Neogene strata are widely distributed in the southeast corner of the huge Longzhong Basin at Tianshui, Gansu Province, northern central china. Hipparion weihoense, a typical member of late Middle Miocene Bahean stage, was recently excavated at Yaodian along a well-exposed outcrop. Owing to the importance of the Bahean stage in the mammalian evolution and its potential for environmental change, we suggested a name of Yaodian Formation for the stratigra- phy, which is correlated to the Bahe Formation at Lantian, Shaanxi. High resolution paleomagnetic dating of the section shows that the Yaodian Formation covers the period between 11.67 Ma and 7.43 Ma, with the site bearing Hipparion weihoense being estimated at about 10.54―10.30 Ma, providing first magnetostratigraphic chronology for the Bahean Stage. The Yaodian Formation consists of fluvial channel deposits (11.67―10.40 Ma) at the bottom, floodplain deposits in the middle (10.40―9.23 Ma) and shallow lake sediments at the top (9.23―7.43 Ma). This upward fining sequence suggests that the relief in nearby mountain ranges such as West Qinling to the south and Huajia Ling to the north was greatly reduced after long-term denudation, fluvial transport capacity was low, and finally the drainage system was disintegrated, replaced with broad-shallow lakes in which only fine sediments like mud and marlite were deposited, indicating an old stage of development of a planation surface. A remarkable shift in ecology and climatic environment was found at 7.4―7.7 Ma when paleoclimate changed from early warm humid to late dry as indicated by sedimentary facies changed from early shallow lake sequence to late eolian red clays and a former coniferous-deciduous mixed forest was replaced by grassland, leading to great growth of Hipparion Fauna of Baodean stage in the region. Therefore, it is estimated that the present high relief of Qinling and drainage pattern did not come into being until Late Pliocene in response

关键词： Bahean stage,magnetostratigraphy,Yaodian Formation,Neogene,Longzhong Basin.

Soil Organic Carbon Storage in china

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Pedosphere 2004年第4期14卷 491-500页

作者： XIEXian-Li SUNBo ZHOUHui-Zhen LIAn-Bo InstituteofSoilscience ChineseAcademyofSciencesNanjing210008（China）. Geographycollege NanjingNormalUniversityNanjing210097（China）

Soil organic carbon (SOC) storage under different types of vegetations in china were estimated using measured data of 2 440 soil profiles to compare SOC density distribution between different estimates, to map the soil organic carbon stocks under different types of vegetation in china, and to analyze the relationships between soil organic carbon stocks and environmental variables using stepwise regression analyses. Soil organic carbon storage in china was estimated at 69.38 Gt (10 15 g). There was a big difference in SOC densities for various vegetation types, with SOC distribution closely related to climatic patterns in general. Stepwise regression analyses of SOC against environmental variables showed that SOC generally increased with increasing precipitation and elevation, while it decreased with increasing ***, the important factor controlling SOC accumulation for forests was elevation, while for temperate steppes mean annual temperature dominated. The more specific the vegetation type used in the regression analysis, the greater was the effect of environmental variables on SOC. However, compared to native vegetation, cultivation activities in the croplands reduced the influence of environmental variables on SOC.

关键词： china environmental factors soil organic carbon storage vegetation

Effect of lead on survival, locomotion and sperm morphology of Asian earthworm, Pheretima guillelmi

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Journal of environmental sciences 2009年第5期21卷 691-695页

作者： ZHENG Rongquan, LI Canyang college of chemistry and Life science, Zhejiang normal university, Jinhua 321004, china. [a]college of chemistry and Life science Zhejiang Normal University Jinhua 321004 China

To provide basic toxicity data for formulating risk characterization benchmarks, the effects of lead on survival, locomotion, and sperm morphology were investigated in the Asian earthworm Pheretima guillelmi. The LC50 of P. guiUelmi for 7 and 14 d were 4285＋339 mg/kg and 3207＋248 mg/kg, which shows P. guillelmi can tolerate a higher concentration of lead nitrate. The average weight of the surviving earthworms decreased at concentration of 2800 mg Pb/kg soil, and the locomotor ability of earthworms exposed to a range of soil Pb concentrations showed a general decrease with increasing Pb concentrations. We also presented data depicting the sperm morphology of earthworms, which shows potential as a sensitive biomarker for measuring the effects of heavy metal on reproduction.

关键词： lead Pheretima guillelmi sperm morphology locomotion