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Exploiting pattern and sustainable development of marginal lands in the Three Gorge Reservoir Areas

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Journal of Environmental sciences 2001年第2期13卷 173-179页

作者： WU Gang, LI Jing, KONG Hong mei, ZHAO Jing zhu, GAO Lin (Department of Ecology system, research center for Eco Environmental sciences, chinese academy of sciences, Beijing 100085, China) Department of Ecology system Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China.

This paper studied the distribution and utilization status, reasonable exploitation patterns and potential productivity, and sustainable development of marginal lands in the Three Gorge Reservoir Areas. It has been pointed that problems of the soil fertility degradation, poor productivity in crop lands, natural disasters and environmental deterioration existed in all the exploited marginal lands. In order to maintain the sustainability of the marginal lands, following measure have been proposed: prohibiting cultivation in the crop lands with a slope more than 25°, restoring vegetation in the slope more than 25°, strengthening the basic agricultural construction, establishing the production base of woody feeds and oils, establishing a multi dimensional management model with reasonable structure and optimum function for forestry, agriculture and fishing.

关键词： marginal lands utilization pattern sustainable development Three Gorge Reservoir Are4

In situ adsorption-catalysis system for the removal of o-xylene over an activated carbon supported Pd catalyst

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Journal of Environmental sciences 2009年第7期21卷 985-990页

作者： HUANG Shaoyong, ZHANG Changbin, HE Hong research center for Eco-Environmental sciences, chinese academy of sciences, Beijing 100085, China. [a]research center for Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 China

An activated carbon （AC） supported Pd catalyst was used to develop a highly efficient in situ adsorption-catalysis system for the removal of low concentrations of o-xylene. In this study, three kinds of Pd/AC catalysts were prepared and tested to investigate the synergistic efficiency between adsorption and catalysis for o-xylene removal. The Pd/AC catalyst was first used as an adsorbent to concentrate dilute o-xylene at low temperature. After saturated adsorption, the adsorbed o-xylene was oxidized to CO2 and H20 by raising the temperature of the catalyst bed. The results showed that more than 99% of the adsorbed o-xylene was completely oxidized to CO2 over a 5% Pd/AC catalyst at 140℃. Brunauer-Emmett-Teller （BET） analysis, scanning electron microscopy （SEM）, temperatureprogrammed desorption （TPD）, and temperature-programmed oxidation （TPO） were applied to investigate the physical properties of o-xylene adsorption-desorption and the in situ adsorption-catalysis activity of the AC support and Pd/AC catalyst. A synergistic relationship between the AC support and the active Pd species for the removal of low concentrations of o-xylene was established.

关键词： in situ adsorption-catalysis Pd/AC volatile organic compounds

Adsorption-desorption behavior of acetochlor to soils in the presence of some environmental substances

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Journal of Environmental sciences 2002年第2期14卷 269-276页

作者： YE Chang ming, LEI Zhi fang (research center for Eco Environmental sciences, chinese academy of sciences, Beijing 100085, China. research center for Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 Chin

The behavior of herbicide acetochlor adsorption desorption to soil in the presence of humic acid (HA), anionic surfactant sodium dodecylbenzene sulfonate (SDBS), cationic surfactant hexadecyltrimethyl ammonium bromide (HDAB) and NH 4NO 3 as a chemical fertilizer was studied. Observed acetochlor adsorption isotherm were well described using Freundlich isotherm equation, from which the desorption isotherm equation has been deduced. The deduced equation can more directly describe acetochlor desorption process. The results showed that the enhance of acetochlor adsorption capacity by solid HA was greater than by soluble HA. The presence of NH 4NO 3 can slightly enhance acetochlor adsorption to soil by comparison with that measured in NH 4NO 3 free solution. In soil water system, surfactant acetochlor interaction is very complex, and the surfactant adsorptions as well as acetochlor adsorption need to be considered. When acetochlor soil suspensions contained lower concentration SDBS or HDAB (40 mg/L), K f for acetochlor adsorption was decreased in comparison to that measured in SDBS or HDAB free solution. When acetochlor soil suspensions contained higher concentration SDBS or HDAB (corresponding 1400 mg/L or 200 mg/L), K f for acetochlor adsorption was increased in comparison to that measured in SDBS or HDAB free solution.

关键词： adsorption desorption acetochlor humic acid surfactants ammonium nitrate soil

Dynamic analysis and assessment for sustainable development

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Journal of Environmental sciences 2002年第1期14卷 88-94页

作者： SHI Xiao\|qing (Department of systems Ecology, research center for Eco\|Environmental sciences, chinese academy of sciences, Beijing 100085, China. ) Department of systems Ecology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The assessment of sustainable development is crucial for constituting sustainable development strategies. Assessment methods that exist so far usually only use an indicator system for making sustainable judgement. These indicators rarely reflect dynamic characteristics. However, sustainable development is influenced by changes in the social\|economic system and in the eco\|environmental system at different times. Besides the spatial character, sustainable development has a temporal character that can not be neglected; therefore the research system should also be dynamic. This paper focuses on this dynamic trait, so that the assessment results obtained provide more information for judgements in decision\|making processes. Firstly the dynamic characteristics of sustainable development are analyzed, which point to a track of sustainable development that is an upward undulating curve. According to the dynamic character and the development rules of a social, economic and ecological system, a flexible assessment approach that is based on tendency analysis, restrictive conditions and a feedback system is then proposed for sustainable development.

关键词： sustainable development assessment dynamic analysis

Anaerobic　biodegradability　of　terephthalic　acid　and　its　inhibitory　effect　on　anaerobic　digestion

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Journal of Environmental sciences 1994年第2期6卷 180-188页

作者： Kuang Xin Wang Jusi(research center for Eco-Environmental sciences, chinese academy of sciences, Beijing 100085, China)

The behavior of terephthalic acid (TPA) in anaerobic system has been studied bysemicontinuous bioassays under mesophilic condition with artificial TPA production wastewater. Theeffect of different loading rate of TPA on anaerobic digestion was studied under certain CODloading rate. The results showed that the TPA could be degraded anaerobically within a relativelylow range. The degradable concentration of TPA was less than 500 mg/L in the digester, higherconcentration of TPA could not be degraded totally and the rate of degradation might decrease withthe increase of feed amount. The inhibition is related to both loading rate and accumulatedconcentration of TPA in the digesters.

关键词： anaerobic biodegradability terephthalic acid inhibitory effect semi-continuous bioassay ac-cumulated concentration .

A primary study of the correlation between the net air-sea heat flux and the interannual variation of western North Pacific tropical cyclone track and intensity

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Acta Oceanologica Sinica 2011年第6期30卷 27-35页

作者： WU Liang WEN Zhiping HUANG Ronghui center for monsoon and Environment research/Department of Atmospheric sciences Sun Yat-sen University Guangzhou 510275 China center for monsoon system research Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China

A singular value decomposition （SVD） analysis is carried out to reveal the relationship between the interannual variation of track and intensity of the western North Pacific tropical cyclones （WNPTCs） in the tropical cyclone （TC） active season （July–November） and the global net air-sea heat flux （Q net ） in the preceding season （April–June）. For this purpose, a tropical cyclone track and intensity function （TIF） is defined by a combination of accumulated cyclone energy （ACE） index and a cyclone track density function. The SVD analysis reveals that the first mode is responsible for the positive correlation between the upward heat flux in the tropical central Pacific and the increased activity of western North Pacific （WNP） TIF, the second mode for the positive correlation between the upward heat flux in the North Indian Ocean and the northeastward track shift of WNPTCs and the third mode for the negative correlation between the upward heat flux in mid-latitude central Pacific and the northwest displacement of the WNP TC-active center. This suggests that Q net anomalies in some key regions have a substantial remote impact on the WNP TC activity.

关键词： tropical cyclone western North Pacific the net air-sea heat flux (Q net ) interannual variation

A novel integrated step-feed biofilm process for the treatment of decentralized domestic wastewater in rural areas of China

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Journal of Environmental sciences 2010年第3期22卷 321-327页

作者： Hanwen Liang, Min Gao, Junxin Liu, Yuansong Wei, Xuesong Guo research center for Eco-Environmental sciences, chinese academy of sciences, Beijing 100085, China. [a] research center for Eco-Environmental sciences Chinese Academy of Sciences Beijing 100085 China

For wastewater treatment in rural areas, a novel three-stage step-feed wastewater treatment system, combined with a drop-aeration biofilm process, was tested in the laboratory to investigate its performance in removing suspended solids （SS）, chemical oxygen demand （COD）, NH4＋-N, total nitrogen （TN）, and total phosphorus （TP）. The removal rates of SS, COD and NH4＋-N were 90%, 80%, and 90% in efluent concentrations less than 10 mg/L, 50 mg/L and 8 mg/L, respectively. The TP removal rate was less satisfactory. The C/N ratio in the raw wastewater was often less than 3.5, and the removal efficiency of TN was therefore limited. A carbon-release batch experiment was carried out to measure the feasibility of enhancing denitrification at low influent C/N ratios. The result showed that the C/N could be over 9.0 in the supernatant. Polymerase chain reaction denaturing gradient gel electrophoresis technology was used to reveal the changes in the bacterial community during different stages of the integrated step-feed biofilm process. The results showed that banding patterns and the distribution of dominant bands for the same experimental period in different aerobic zones were similar. Phylogenetic analysis indicated that lanes 10, 11 and 12, which presented three aerobic zones at the same operation period, had the closest phylogenetic relationship among the lanes.

关键词： step-feed biofilm removal efficiency PCR-DGGE C/N ratio

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 Eco-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-22 + H2O2, HCFC-22 + H2O2+O2, HFC-134A + H2O2 and HFC-134A + H2O2+ O2 systems were studied.H2O2 was irradiated by low pressure mercury lamp and produced OH radicals. The OH radicals can initiate photooxidation of HCFC-22 and 134A. The products of photooxidation were determined by a Fourier Transform infrared Spectroscopy with a 20ml long path cell. The products were COF2,CO2, HCI, H2O and HF for HCFC-22 + H2O2 system, HO, CO2, HCI and HF for HCFC-22 +H2O2 +O2 system, HCOF, CF3OOCF3,CO2, H2O and HF for HFC-134A +H2O2 system, HCOF, CO2, H2O, and HF for HFC-134A + H2O2+ O2 system. Based on those results, the mechanisms of photooxidation were suggested.

关键词： hydrochlorofluorocarbons hydrofluorocarbons photooxidation OH radicals FTIR.

Effects of Positron Diffusion and Its Application in Composite system

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Journal of Materials Science & Technology 2000年第3期16卷 311-314页

作者： Jian JIANG, Xinzhang ZHOU and ChiWei LUNG (International center for Materials Physics, Institute of Metal research, chinese academy of sciences, Shenyang 110015, China) International center for Materials Physics Institute of Metal Research Chinese Academy of Sciences Shenyang 110015 China

The effects of positron diffusion on the measured S parameter have been investigated by a point-source diffusion model and a δ function method. Firstly, the theoretical analyses of the effects are presented for the samples of a homogeneous semi-infinite medium and a film of definite thickness. Then the results are used to analyze the S parameters in several composite systems and interface models.

关键词： Effects of Positron Diffusion and Its Application in Composite system