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Applications of synchrotron-based X-ray techniques in environmental science

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Science china Chemistry 2010年第12期53卷 2529-2538页

作者： LUO Lei & ZHANG ShuZhen 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

Synchrotron-based X-ray techniques have been widely applied to the fields of environmental science due to their element-specific and nondestructive properties and unique spectral and spatial resolution *** techniques are capable of in situ investigating chemical speciation,microstructure and mapping of elements in question at the molecular or nanometer scale,and thus provide direct evidence for reaction mechanisms for various environmental *** this contribution,the applications of three types of the techniques commonly used in the fields of environmental research are reviewed,namely X-ray absorption spectroscopy (XAS),X-ray fluorescence (XRF) spectroscopy and scanning transmission X-ray microscopy (STXM).In particular,the recent advances of the techniques in china are elaborated,and a selection of the applied examples are provided in the field of environmental ***,the perspectives of synchrotron-based X-ray techniques are *** their great progress and wide application,the techniques have revolutionized our understanding of significant geo-and bio-chemical *** is anticipatable that synchrotron-based X-ray techniques will continue to play a significant role in the fields and significant advances will be obtained in decades ahead.

关键词： synchrotron spectroscopy spectromicroscopy environmental science

Carbon dioxide release due to change in land use in china mainland

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Journal of environmental sciences 1994年第3期6卷 287-295页

作者： Wang Xiaoke Zhuang Yahui Feng Zongwei(research center for {2.-environmental sciences, chinese academy of sciences, beijing 100085, china)

The carbon pool and emission of carbon dioxide from terrestrial ecosystems in chinahave been estimated. The carbon pool is 2.51×10￣9-2..2.10￣9 ton C in vegetation, and 49. 7×10￣9ton C in soil. The carbon dioxide release from terrestrial ecosystems is 0.0317× 10￣9- 0. 195× 10￣9ton C due to changes in land-use in recent years, mainly caused by deforestation and degradation ofgrassland. This carbon release due to changes in land-use is approximately 17% of the current carbondioxide emission from fossil fuel combustion and cement production in china. As compared withthe global carbon pool, the carbon pool in vegetation and in soil in china are 1.8% and 3.3% ofthe global figures, respectively.

关键词： carbon pool, carbon dioxide release terrestrial ecosystems.

Effect of temperature on the sorption and desorption of perfluorooctane sulfonate on humic acid

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Journal of environmental sciences 2010年第3期22卷 355-361页

作者： Chengxia Jia, Chun You, Gang Pan 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

Sorption and desorption of perfluorooctane sulfonate （PFOS） on humic acid at different temperatures were studied. It was found that the sorption process could be modeled with power kinetic equation very well, suggesting that diflusion predominated the sorption of PFOS on the humic acid. The sorption capacity was doubled when the temperature increased from 5 to 35°C, and thermodynamics parameters △G0 was calculated to be –7.11 to –5.04 kJ/mol, △H0 was 14.2.kJ/mol, and △S 0 was 69.5 J/（mol·K）, indicating that the sorption was a spontaneous, endothermic, and entropy driven process. Desorption hysteresis occurred at all studied temperatures which suggested that humic acid may be an important sink of PFOS in the environment.

关键词： perfluorooctane sulfonate sorption desorption temperature humic acid

Determination　of　herbicides　atrazine　and　butachlor　in　soil　by　high　performance　liquid　chromatography

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Journal of environmental sciences 1996年第4期8卷 504-506页

作者： Xu Weibing (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

A Liquid Chromatographic procedure was described for simultaneous determination atrazine and butachlor in soil with a diode-array-detector(DAD).Unequivocal identification by Rt alone,however,is sometimes difficult. The UV spectra offer a viable alternative to *** distinct differences in Rt and UV of the peaks are noteworthy. UV spectra are extremely helpful and served to accurately identify the various component. Soil samples containing herbicide residues were extracted on a shaker using dichloromethane. The extractions were finally concentrated to 1 ml by a K-D concentrator then the residues were quantitated by peak height. Detection limits for atrazine and butachlor were 0.1 ppb and 0.8 ppb respectively. Fortified at 5.0 ng,10. 0 ng, and 50.0 ng levels,the recoveries of atrazine (n= 8)were 88.4%,95. 1% and 91. 6%. Fortified at 10. 0 ng,50. 0 ng and 80.0 ng levels,the recoveries of butachlor (n=8) were 89. 8%,91.2. and 87.4%,respectively.

关键词： RP-HPLC,atrazine butachlor herbicids soil.

In situ DRIFTS study of hygroscopic behavior of mineral aerosol

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Journal of environmental sciences 2010年第4期22卷 555-560页

作者： Qingxin Ma,Hong He,Yongchun Liu State Key Laboratory of environmental Chemistry and ecotoxicology,{2. center for eco-environmental sciences,chinese academy of sciences,beijing 100085,china. [a] State Key Laboratory of environmental Chemistry ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

In situ diffusion reflectance infrared Fourier transform spectroscopy was used to study the water adsorption on mineral oxides （SiO2. a-Al2.3, MgO, Fe2.3, TiO2.. The results showed that all the water adsorption isotherms were well fitted with the Brunauer-Emmett-Teller （BET）-Ⅲ type equation, with the calculated monolayers occurring at 2.%-30% relative humidity. It showed that about 1-5 layers of water adsorbed on oxides surfaces in ambient relative humidity （2.%-90%）. The measured deliquescence relative humidity of NaCl was （74 ± 1）%, which demonstrated that DRIFTS is a useful method for the study the hygroscopic behavior of mineral dust. In addition, the limits of DRIPTS were also discussed.

关键词： DRIFTS mineral oxides water adsorption hygroscopicity

Population growth，economic growth，technology changes in relation to environmental changes──A theoretical modelling analysis of environmental changes

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Journal of environmental sciences 1994年第4期6卷 412-421页

作者： Hu Angang(research center for {2.-environmental sciences ,chinese Acaderny of sciences. beijing 100085 , china)

This paper mainly deals with the impact of three major factors , namely population growth,economic growth and technology changes, on the changes of environmental quality. It presents a curve ofenvironmental changes in relation to demographic transition and process of industrialization. It concludesthat a major way of improving environmental quality is to intensify pollution decreasing technical factorsand that control of population growth will also reduce the pressure on the environment.

关键词： Population growth economic growth environmental changes ttchnolilgy change.

PCDD／Fs in sodium pentachlorophenate（Na－PCP） and human blood， milk and sediment samples from chinese schistosomiasis areas

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Journal of environmental sciences 1995年第1期7卷 52-59页

作者： Jiang Ke Chen Yudong Li Lingjun(research center for {2.-environmental sciences,chinese academy of sciences,beijing 100085,china)

ＰＣＤＤ／Ｆｓｉｎｓｏｄｉｕｍｐｅｎｔａｃｈｌｏｒｏｐｈｅｎａｔｅ（Ｎａ－ＰＣＰ）ａｎｄｈｕｍａｎｂｌｏｏｄ，ｍｉｌｋａｎｄｓｅｄｉｍｅｎｔｓａｍｐｌｅｓｆｒｏｍＣｈｉｎｅｓｅｓｃｈｉｓｔｏｓｏｍｉａｓｉｓａｒｅａｓ... 详细信息

ＰＣＤＤ／Ｆｓｉｎｓｏｄｉｕｍｐｅｎｔａｃｈｌｏｒｏｐｈｅｎａｔｅ（Ｎａ－ＰＣＰ）ａｎｄｈｕｍａｎｂｌｏｏｄ，ｍｉｌｋａｎｄｓｅｄｉｍｅｎｔｓａｍｐｌｅｓｆｒｏｍＣｈｉｎｅｓｅｓｃｈｉｓｔｏｓｏｍｉａｓｉｓａｒｅａｓＪｉａｎｇＫｅ；ＣｈｅｎＹｕｄｏｎ...

关键词： sodium pentacuorophenate PCDD/Fs molluscacde.

Treatment of black liquor from the papermaking industry by acidification and reuse

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Journal of environmental sciences 2003年第5期15卷 697-700页

作者： YANG Wen bo, MU Huan zhen, HUANG Yan chu (research center for {2. environmental sciences, chinese academy of sciences, beijing 100085, china. research center for {2.-environmental sciences Chinese Academy of Sciences Beijing 100085 Chin

Two different kinds of black liquor from the papermaking industry were treated by acidification and reuse. The experimental parameters and conditions were discussed in detail. The experimental results indicated that the treatment process mentioned in this article is an effective process for the treatment of black liquor from the papermaking industry. By the treatment, the solid materials in black liquor are transferred into two by products and the other components are reused or evaporated. Thus, no wastewater except some condensation water would be discharged in pulping process and the problem of pollution of black liquor would be effectively solved.

关键词： black liquor acidification reuse lignin water reducing agent

Combined fluorescence and electrochemical investigation on the binding interaction between organic acid and human serum albumin

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Journal of environmental sciences 2009年第3期21卷 373-379页

作者： CHEN Yan-Min,GUO Liang-Hong State Key Laboratory of environmental Chemistry and ecotoxicology,{2. center for eco-environmental sciences,chinese academy of sciences,beijing 100085,china. [a]State Key Laboratory of environmental Chemistry and ecotoxicology Research Center for Eco-environmental Sciences Chinese Academy of Sciences Beijing 100085 China

Human serum albumin （HSA） is a plasma protein responsible for the binding and transport of fatty acids and a variety of exogenous chemicals such as drugs and environmental pollutants. Such binding plays a crucial role in determining the ADME （absorption, distribution, metabolism, and excretion） and bioavailability of the pollutants. The binding interaction between HSA and acetic acid （C2., octanoic acid （C8） and dodecanoic acid （C12. has been investigated by the combination of site-specific fluorescent probe, tryptophan intrinsic fluorescence and tyrosine electrochemistry. For the study of the fatty acid interaction with the two drug-binding sites on HSA, two fluorescent probes, dansylamide and dansyl-L-proline were employed in the displacement measurements. Intrinsic fluorescence of tryptophan in HSA was monitored upon addition of the fatty acids into HSA. Electrocatalyzed response of the tyrosine residues in HSA by a redox mediator was used to investigate the binding interaction. Qualitatively, observations from these three approaches were very similar. HSA did not show any change in the fluorescence and electrochemical experiments after mixing with C2. suggesting there is no significant interaction with the short-chain fatty acid. For C8, the measured signal dropped in a single-exponential mode, indicating an independent and non-cooperative binding. The calculated association constant and binding ratio were 3.1 × 10^6 L/mol and 1 with drug binding Site Ⅰ, 1.1 × 107 L/mol and 1 with Site Ⅱ, and 7.0× 0^4 L/mol and 4 with the tryptophan site, respectively. The measurements with C12.displayed multiple phases of fluorescence change, suggesting cooperativity and allosteric effect of the C12.binding. These results correlate well with those obtained by the established methods, and validate the new approach as a viable tool to study the interactions of environmental pollutants with biological molecules.

关键词： absorption, distribution, metabolism, and excretion (ADME) organic acid human serum albumin fluorescence electrochemistry