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Adsorption of atrazine by natural organic matter and surfactant dispersed carbon nanotubes

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Journal of environmental sciences 2010年第8期22卷 1195-1202页

作者： Baoyou Shi, Xiaoyan Zhuang, Xiaomin Yan, Jiajuan Lu, Hongxiao Tang State Key Laboratory of environmental Aquatic Chemistry, research center for eco-environmental sciences, chinese academy of sciences, beijing 100085, china. [a] State Key Laboratory of environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The aggregation and dispersion behaviors of carbon nanotubes （CNTs） can regulate the environmental spread and fate of CNTs, as well as the organic pollutants adsorbed onto them. In this study, multi-walled carbon nanotubes （MWNTs） and single-walled carbon nanotubes （SWNTs） were surface modified with humic acids from different sources and with surfactants of different ionic types. The dispersion stability of surface modified CNTs was observed by UV-Vis spectrophotometry. The effect of humic acid and surfactant dispersion on the adsorption of atrazine by CNTs was investigated by batch equilibrium experiments. Both humic acid and surfactant could effectively disperse MWNTs, but not SWNTs, into stable suspensions under the studied conditions. Surface modified CNTs had a greatly reduced capacity for adsorption of atrazine. The inhibitory effect of peat humic acid was relatively stronger than that of soil humic acid, but the two surfactants had a similar inhibitory effect on atrazine adsorption by the two CNT types. Increases in surfactant concentration resulted in rapid decreases in the adsorption of atrazine by CNTs when the surfactant concentration was less than 0.5 critical micelle concentration.

关键词： carbon nanotubes adsorption dispersion atrazine

eco-environmental problems and protectionin Tumen River development

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Journal of environmental sciences 1995年第3期7卷 317-324页

作者： Ye Changming Yan Hai Ding Mei(research center for eco-environmental sciences, chinese Acaderny of Sceiences, beijing 100085, china)

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Ｅｃｏ－ｅｎｖｉｒｏｎｍｅｎｔａｌｐｒｏｂｌｅｍｓａｎｄｐｒｏｔｅｃｔｉｏｎｉｎＴｕｍｅｎＲｉｖｅｒｄｅｖｅｌｏｐｍｅｎｔＹｅＣｈａｎｇｍｉｎｇ；ＹａｎＨａｉ；ＤｉｎｇＭｅｉ（ＲｅｓｅａｒｃｈＣｅｎｔｅｒｆｏｒＥｃｏ－ＥｎｖｉｒｏｎｍｅｎｔａｌＳｃｉ...

关键词： regional ecology ecological division Tumen River china.

Simulating study on the effect of acid precipitation on forest soil weathering

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Journal of environmental sciences 1991年第3期3卷 61-69页

作者： Liu Quanyou and Li Changshengresearch center for eco-environmental sciences,chinese academy of sciences,beijing 100083,china

The effect of acid rain on the forest soils in china was discussed on the basis of simulating studies. The soils were collected from five typical areas, including Chongqing in Sichuan Province and Guiyang in Guizhou Province, where there has been heavier acid rain in southwest china, and Huitong in Hunan Province, Zhouzhi in Shaanxi Province, and Xinglong in Hebei Province, all of which were selected as control. Field investigation and sampling were made in the typical forests in all the above five areas. The relationship between pH values in precipitation and rates of soil weathering, the difference between the rates of soil weathering in different areas, and the cause of such a difference, have been worked out. The prediction was also conducted on the supply dynamics of nutrient and toxic elements in various forest ecosystems which were affected by acid deposition in order to understand the long-term effects of acid precipitation on the forest ecosystems studied.

关键词： acid precipitation forest ecosystems soil weathering.

Construction of WCB-11:A novel phiYFP arsenic-resistant whole-cell biosensor

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Journal of environmental sciences 2010年第9期22卷 1469-1474页

作者： Qing Hu ,Li Li,Yanjuan Wang,Wenjuan Zhao,Hongyan Qi,Guoqiang Zhuang Department of environmental Bio-Technology,research center for eco-environmental sciences,chinese academy of sciences,beijing 100085,china. [a] Department of environmental Bio-Technology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The prediction and assessment of environmental pollution by arsenic are important preconditions of advocating environmental protection and human health risk assessment. A yellow fluorescent protein-based whole-cell biosensor for the detection of arsenite and arsenate was constructed and tested. An arsenic-resistant promoter and the regulatory gene arsR were obtained by PCR from the genome ofEscherichia coli DH5ct, andphiYFP was introduced into E. coli DH5ct as a reporter gene to construct an arsenic-resistant whole-cell biosensor （WCB-11） in which phiYFP was expressed well for the first time. Experimental results demonstrated that the biosensor has a good response to arsenic and the expression ofphiYFP. When strain WCB-11 was exposed to As^3＋ and As^5＋, the expression of yellow fluorescence was time-dependent and dose-dependent. This engineered construct is expected to become established as an inexpensive and convenient method for the detection of arsenic in the field.

关键词： arsenic reporter gene whole-cell biosensor yellow fluorescent protein (phiYFP)

The associations between the environmental exposure to polychlorinated biphenyls (PCBs) and breast cancer risk and progression

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Science china Chemistry 2010年第5期53卷 974-979页

作者： LIU SiJin ,ZHANG ShuPing,QU Chen,LIU Wei & DU YuGuo State Key Laboratory of environmental Chemistry and ecotoxicology research center for eco-environmental sciences,chinese academy of sciences,beijing 100085,china 1. State Key Laboratory of environmental Chemistry and ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Polychlorinated biphenyls(PCBs) are chlorinated biphenyl compounds with wide applications in the *** spite of a ban on their production in the late 1970s,PCBs,as a group of POPs,are still persistent and widely spread in the environment,posing potential threats to human *** role of PCBs as etiologic agents for breast cancer has been intensively explored in a variety of in vivo,animal and epidemiologic *** investigations indicated higher levels of PCBs in mammary tissues or sera corresponded to the occurrence of breast cancer,but later studies showed no positive association between PCB exposure and breast cancer *** recent data suggested that the CYP1A1 m2 polymorphisms might add increased risk to the etiology of breast cancer in women with environmental exposure to *** are implicated in advancing breast cancer progression,and our unpublished data reveals that PCBs activate the ROCK signaling to enhance breast cancer ***,the correlation between PCB exposure and breast cancer risk warrants further careful investigations.

关键词： Polychlorinated biphenyls (PCBs) environmental exposure CYP1A1 polymorphisms breast cancer risk tumor progression

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贵州民族研究 2024年第4期 2-2页

作者： center for chinese Social sciences research Assessment 南京大学中国社会科学研究评价中心

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The roles of a decision support system in applying forest ecosystem management in Northeast china

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Science china(Technological sciences) 2006年第z1期49卷 9-18页

作者： DAI Limin, ZHENG Bofu, Guofan Shao & ZHOU Li State Key Lab of Systems ecology, research center for eco-environmental sciences, chinese academy of sciences, beijing 100085, china Institute of Applied ecology, chinese academy of sciences, Shenyang 110016, china Department of Forestry and Natural Resources, Purdue University, West Lafayette, IN 47907, USA Graduate University of chinese academy of sciences, beijing 100101, china 1. State Key Lab of Systems ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China2. Institute of Applied Ecology Chinese Academy of Sciences Shenyang 110016 China3. Department of Forestry and Natural Resources Purdue University West Lafayette IN 47907 USA4. Graduate University of Chinese Academy of Sciences Beijing 100101 China

Forest ecosystems provide a variety of services and forest ecosystem management (FEM) is an effective approach to maximize the services. Because of the complexity of forest ecosystems, the applications of FEM can be facilitated with decision support systems (DSS) that recognize and incorporate ecological and socio-economic variables. With the rapid development of computation and information technologies, DSS have been advanced in many ways. Traditional forest management within a forestry unit in china is planned on a yearly basis. The planning itself remains primarily a verbal concept as there are no quantitative decision-support tools available to translate the concept into forest management actions. For the purposes of FEM at the management level, a forest management DFF, FORESTAR, has been developed under a framework of geographic information system (GIS) and forest models. The paper explained the intelligent modeling mechanisms and demonstrated how the applications of FEM can be strengthened with the applications of FORESTAR.

关键词： forest functions, forested landscapes, forest services, forest models, geographic information systems.

Comparison　of　some　atmospheric　chemical　modeling　schemes

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Journal of environmental sciences 1997年第2期9卷 58-76页

作者： Shen Ji,\ Zhao Qianxue research center for eco Enviromental sciences,chinese academy of sciences,beijing 100085,china

The comparison of five atmospheric chemical modeling schemes was presented from accuracy,efficiency and progamming in term of Carbon bond Mechanism IV of atmospheric chemical reactions. The major results were as follows. The classical Gear scheme can provide an accurate solution and it is easy for programming by a computer automatically. The sparse matrix Gear type scheme can also provide an accurate solution but much faster than classical Gear scheme. QSSA,EBI and hybrid schemes can run with much longer time step without sacrificing of accuracy, therefore, much efficiently. If analytical solution is obtained by EBI scheme the accuracy and efficiency are much better.

关键词： atmospheric chemical modeling photochemical reaction mechanism stiff ordinary differential equations.

Effects of allelochemicals on activity of nitrate reductase

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Journal of environmental sciences 2000年第1期12卷 127-130页

作者： MA Rui\|xia (research center for eco\|environmental sciences, chinese academy of sciences, beijing 100085, china)

Study on the effects of allelochemicals such as trans \|ferulic acid ( t \|FA), benzoic acid (BA) and p \|hydroxybenzoic acid ( p \|HA), isolated from decomposed wheat straw on the activity of nitrate reductase at different concentrations of allelochemicals and different pH is described. t \|FA (0.26, 2.58 and 5.15 mmol/L) and BA (4.09, 8.19 mmol/L) showed a certain inhibition to the activity of nitrate reductase. The highest inhibition rate was 18.40%, but BA (0.41 mmol/L) and p \|HA (0.36, 1.81 and 3.62 mmol/L) showed stimulation, the more strong stimulation rate was 15.80%. At pH 6 condition, the activity of nitrate reductase was stronger inhibited than pH 7 and pH 8, but the mixture of 3 allelochemicals at pH 6 showed a stimulation. The mixture, however, at pH 7 and pH 8 showed some inhibition. It was found that there was a relationship between production of NO\+-\-2 and transformation of NO\+-\-3.

关键词： allelochemicals nitrate reductase denitrification activity CLC number: S131 Document code: A