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Adsorption　characteristics　of　copper　in　rivers　contaminated　by　acid　mine　drainage　from　copper　mine

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Journal of environmental sciences 1996年第1期8卷 28-37页

作者： Luan Zhaokun Chen Ming Tang Hongxiao(research center for {2.-environmental sciences,chinese academy of sciences,beijing 100085,china)

In this paper, the partitioning of copper between surfacial sediments and overlaying water in Dawu-Le An River, which was contaminated by acid mine drainage resulted from mining activities,was studied by field investigation and acid dissolution *** adsorption experiments were carried out to study the adsorption of copper on amorphous iron oxyhydroxide and ore tailing *** results showed that it was the binding of copper onto the surface of amorphous Fe/Al oxyhydroxides and ore tailing particles that regulated the concentrations of dissolved Cu at downstream of Dawu River and its inlet into Le An River.A significant part of adsorbed copper was likely to be associated with amorphous Fe/Al oxyhydroxides coated on the surface of ore tailing particles. A simplified surface complexation model can be used to describe the adsorption behavior in the river.

关键词： copper mine adsorption behavior natural waters.

Phosphorus release: A biogeochemical insight from a restored lakeside wetland in the Yangtze-Huaihe region, china

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Journal of environmental sciences 2010年第3期22卷 347-354页

作者： Xiaoling Zhou, Baoqing Shan, Hong Zhang State Key Laboratory of environmental Aquatic Chemistry, research {2. 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 heavy intensification of agriculture in East china since the 1980s caused the decrease of lake area and water storage capacity with impediment of regulation, lake eutrophication and frequent floods. Many restoration projects have been conducted. However, the knowledge of biogeochemical factors that drive nutrient cycles during the early stage of restoration is still limited. We studied the effect of the remediation of a patch of near-shore shallow wetland on the northern bank of Chaohu Lake in the Yangtze-Huaihe region, china, which was used as rice paddy for many years, on the behavior of phosphorus. Redox potential （ORP）, temperature and dissolved oxygen were monitored in situ from May 2.06 to November 2.07. Samples of soil pore water were collected during this time for the determination of different forms of iron and phosphorus. ORP showed a clear transition of the wetland soil from an oxidized state in winter to a reduced state in summer. The decrease of ORP correlated with the release of large amounts of Fe and P. The maxima of total dissolved Fe and total dissolved P in the summer of the s{2.nd year were （13.8 ± 6.8） mg/L and （0.88 ± 0.2.） mg/L, respectively. It is worth noticing that P concentration far exceeded the critical value of lake eutrophication （0.02.mg/L）. The pressure of P release to the adjacent lake during the first two years of wetland restoration from rice fields should be taken into account by environmental policy makers.

关键词： wetland restoration phosphorus eutrophication redox potential iron

eco-environmental susceptibility in Shangyi County,Northern Hebei Province,{2.

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Journal of environmental sciences 1997年第1期9卷 86-94页

作者： Liu Quanyou Chen Liding research center for {2.-environmental sciences,chinese academy of sciences,beijing 100085,china Res. Ctr. for eco-Environ. sciences Chinese Academy of Sciences Beijing 100085 China

In this paper,the eco-environmental susceptibility of Shangyi County,Northern Hebei Province of {2. has been calculated by using the weighted-addition method based on expert's giv- ing a mark to each influencing factor according to their knowledge on the influence of all the factors on eco-environmental *** eco-environmental classification and distribution map were reached based on the above results,its difference is mainly result from the physical conditions and human activity,however the value of eco-environmental susceptibility is only a relative index which can not completely reflect the quality of *** work provided a basis for control- ling the further development of desertification.

关键词： eco-environmental susceptibility weighted addition method.

Photooxidation　of　hydrochlorofluocarbons　and　hydrofluorocarbons　initiated　by　OH　radicals

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Journal of environmental sciences 1996年第2期8卷 228-234页

作者： Zhong Jinxian Mu Yujing Yang Wenxiang(research center for {2.-environmental sciences chinese academy of sciences, beijing 100085, china)Chen Dazhou(chinese center for Certified Reference Materials, beijing 100013, china) Res. Ctr. for eco-Environ. sciences Chinese Academy of Sciences Beijing 100085 China chinese Ctr. for Certified Ref. Mat. Beijing 100013 China

Under simulated atmospheric condition, photoomdation for HCFC-2. + H2.2. HCFC-2. + H2.2.O2. HFC-134A + H2.2.and HFC-134A + H2.2. O2.systems were studied.H2.2.was irradiated by low pressure mercury lamp and produced OH radicals. The OH radicals can initiate photooxidation of HCFC-2. and 134A. The products of photooxidation were determined by a Fourier Transform infrared Spectroscopy with a 2.ml long path cell. The products were COF2.CO2. HCI, H2. and HF for HCFC-2. + H2.2.system, HO, CO2. HCI and HF for HCFC-2. +H2.2.+O2.system, HCOF, CF3OOCF3,CO2. H2. and HF for HFC-134A +H2.2.system, HCOF, CO2. H2., and HF for HFC-134A + H2.2. O2.system. Based on those results, the mechanisms of photooxidation were suggested.

关键词： hydrochlorofluorocarbons hydrofluorocarbons photooxidation OH radicals FTIR.

Major environmental and ecotoxicological processes of heavy metals in Lean River polluted by discharges from mining activities

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Journal of environmental sciences 1999年第3期11卷 322-327页

作者： Wang Zi\|jian SKLEAC, research center for {2.\|environmental sciences, chinese academy of sciences, beijing\ 100085, china 中科院生态环境研究中心北京 100085

This paper summarizes the major environmental and ecotoxicological processes of heavy metals pollution from Dexing Copper Mine in Jiangxi Province based on various findings in the Cooperative ecological research Project (CERP; Tang, 1994). It shows the knowledge necessary to elucidate metal pollution and its ecological implications. Processes devoted to the ecological implication include generation of acid mine drainage, formation of secondary minerals from precipitation, temporal and spatial distribution of metal pollutants in sediments and relevant toxicity, as well as ecosystem alternation which may relate to chemical pollution.\; From the results, it was stated that the major emphasis should be placed on the environmental processes associated with sediment pollution by heavy metals. It shows that ad/desorption on the inorganic minerals, such as Fe/Al oxyhydroxides, play an important role in the immobilization of heavy metals in this river. There were clear indications that metal pollution has resulted in the toxicological and ecological consequences and there would be the risk of secondary pollution in the way of mobilization of bound metals to the overlying water when environmental conditions are varied.

关键词： heavy metal pollution mobility toxicity ecotoxicology.

Lack of nano size effect on electrochemistry of dopamine at a gold nanoparticle modified indium tin oxide electrode

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Science china Chemistry 2010年第8期53卷 1778-1783页

作者： HUANG RongFu & GUO Liang-Hong State Key Laboratory of environmental Chemistry and ecotoxicology {2. center for eco-environmental sciences,chinese academy of sciences,beijing 100085,china 1. State Key Laboratory of environmental Chemistry and ecotoxicology research center for {2.-environmental sciences Chinese Academy of Sciences Beijing 100085 China

Nanometer sized materials have been shown to possess excellent chemical and electrochemical catalytic *** this work,a gold nanoparticle (AuNP) modified indium tin oxide (ITO) electrode was employed for investigating its electro-catalytic *** was deposited on the 3-aminopropyltriethoxysilane (APTES) modified ITO electrode by self-assembly,and was characterized by scanning electron microscopy and cyclic *** the electrochemical reaction of dopamine was very sluggish on the ITO/APTES electrode,it was significantly enhanced after AuNP *** cyclic voltammogram exhibited apparent dependence on the surface coverage of 11 nm AuNPs,which could be rationalized by different modes of mass *** the different sizes of AuNP investigated,the lowest anodic peak potential was observed on 11 nm ***,the potential was still about 50 mV more positive than that obtained on a bulk gold electrode of similar *** is therefore concluded that there is no nanometer size effect of AuNP modified ITO on the electrochemistry of dopamine.

关键词： gold nanoparticle dopamine electrocatalysis indium tin oxide

Effect of elevated CO_2.on CH_4 emission

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chinese Science Bulletin 1999年第13期44卷 1153-1157页

作者： WANG DaliState Key Laboratory of environmental Aquatic Chemistry, research {2. for eco-environmental sciences, chinese academy of sciences , beijing 100085, china State Key Laboratory of environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Science Beijing China

Global CH4 emission may increase under CO2.enrichment condition, which is projected for the future. CO2.enrichment could affect CH4 emission in two ways: （ ⅰ ） Photosynthesis of plants that also include plants in r... 详细信息

Global CH4 emission may increase under CO2./sub> enrichment condition, which is projected for the future. CO2./sub> enrichment could affect CH4 emission in two ways: （ ⅰ ） Photosynthesis of plants that also include plants in rice paddies and natural wetlands will be stimulated under CO2./sub> enrichment condition. CH4 emission rate may be increased due to the accumulation of more plant biomass, root exudes and soil organic matters. （ ⅱ ） Combined with other global warming forces, CO2./sub> enrichment may bring a change of atmospheric temperature and precipitation around the world. CH4 emission will also be changed with the variation of the area and distribution of rice paddies and natural wetlands.

关键词： global change CO2 enrichment CH4 emission.

Determination of atmospheric concentrations of halocarbons in beijing area

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Journal of environmental sciences 1993年第1期5卷 76-82页

作者： Wang Shaobinresearch center for {2.-environmental sciences, chinese academy of sciences, beijing 100085, chinaPeng Lixin and Tang Xiaoyanresearch center of environmental sciences, Peking University, {12. 100871, china research center for {2.-environmental sciences Chinese Academy of Sciences Beijing 100085 China. China

Gas chromatography with ambient temperature injection and frozen-trapped techniques was used to determine the atmospheric concentrations of halocarbons over beijing. Halogenated compounds such as CFC-11, CFC-12. CHCl_3, CCl_4, CH_3CCl_3, CHCl =CCl_2. and CCl2.CCl2.were measured and their concentrations are 109±8, 2.4±13, 47±2., 97±2., 88±2., 11±1 and 17±3 (pptv), respectively.

关键词： GC-ECD atmospheric halocarbons beijing.

Effect of atmospheric aerosols on UV-B radiation reaching the ground

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Journal of environmental sciences 1993年第2期5卷 224-229页

作者： Wang Shaobin Su Weihanresearch center for {2.-environmental sciences, chinese academy of sciences, beijing 100085, china research center of eco-environmental sciences Chinese Academy of Sciences Beijing 100085 China. China

Solar ultraviolet radiation reaching the ground can be reduced due to light scattering of atmospheric aerosols. Aerosol pollution has led to the decrease in biological active UV-B radiation by about 45% and 10% in city and rural areas, respectively. In populated areas, effect of aerosol scattering on UV-B radiation may offset the increased amount of UV-B caused by ozone depletion, but in clean areas such as two poles, ozone depletion may have great damage effects on ecosystems.

关键词： atmospheric aerosol UV-B radiation ozone reduction.