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Journal of environmental Sciences 2016年第1期28卷 62-68页

作者： Gang Li Yingming Li Hongxing Zhang Honghua Li Guanjun Gao Qian Zhou Yuan Gao Wenjuan Li Huizhong Sun Xiaoke Wang Qinghua Zhang State Key Laboratory of environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing Urban Ecosystem research Station Research Center for Eco-Environmental Sciences Chinese Academy of Sciences institute of Environment and Health Jianghan University

Quartz particles are a toxic component of airborne paniculate matter（PM）.Quartz concentrations were analyzed by X-ray diffraction in eighty-seven airborne PM samples collected from three locations in Beijing before,during,and after the Asia-Pacific Economic Cooperation（APEC） Leaders＇ Meeting in *** results showed that the mean concentrations of quartz in PM samples from the two urban sites were considerably higher than those from the rural *** quartz concentrations in samples collected after the APEC meeting,when the pollution restriction lever was lifted,were higher than those in the samples collected before or during the APEC *** quartz concentrations ranged from 0.97 to 13.2 μg/m^3,which were among the highest values amid those reported from other *** highest quartz concentration exceeded the Californian Office of environmental Health Hazard Assessment reference exposure level and was close to the occupational threshold limit values for occupational ***,a correlation analysis showed that quartz concentrations were positively correlated with concentrations of pollution parameters PM10,PM2.5,SO2 and NOx,but were negatively correlated with O3 *** results suggest that the airborne quartz particles may potentially pose health risks to the general population of Beijing.

关键词： Air pollution Carcinogen Haze PM10 Quartz

A review of environmental characteristics and effects of low-molecular weight organic acids in the surface ecosystem

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Journal of environmental Sciences 2014年第5期26卷 935-954页

作者： Min Xiao Fengchang Wu State Key Laboratory of environmental Geochemistry Institute of Geochemistry Chinese Academy of Sciences State Key Laboratory of environmental Criteria and Risk Assessment Chinese Research Academy of Environmental Sciences

Low molecular weight organic acids （LMWOAs） are prevalent on the earth＇s surface. They are vital intermediate products during metabolic pathways of organic matter and participate in the tricarboxylic acid cycle during life activities. Photochemical reactions are pivotal for LMWOAs＇ origination and play a large role in determining their diversity and their ultimate fate. Within the long time that organic matter is preserved in sediments, it can be decomposed and converted to release organic and inorganic pollutants as well as C, N, and P nutrients, which are of potential ecological risk in causing secondary pollution to lake water. The sediment pool is a comprehensive and complex compartment closely associated with overlying water by various biochemical processes, during which LMWOAs play critical roles to transport and transform elements. This article elucidates geochemical behaviors of LMWOAs in the surface environment in details, taking natural water, soil, and aerosol as examples, focusing on reviewing research developments on sources and characteristics, migration and mineralization of LMWOAs and relevant environmental effects. Simultaneously, this review article depicts the categories and contents of LMWOAs or their contribution to DOC in environmental media, and evaluates their importance during organic matter early diagenesis. Through concluding and discussing the conversion mechanisms and influencing factors, the next research orientations on LMWOAs in lake ecosystems are determined, mainly concerning relationships with hydrochemical parameters and microorganisms, and interactions with pollutants. This will enrich the knowledge on organic matter degradation and related environmental effects, and help reconstruct a theoretical framework for organic compound succession and influencing factors, providing basic data for lake eutrophication and ecological risk assessment, conducive to better control over water pollution and proper management of water quality.

关键词： low molecular weight organic acids conversion mechanism pollutants environmental effects ecological risk management of water quality

The westerly fluctuation and water vapor transport over the Qilian-Heihe valley

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Science China Earth Sciences 2004年第z1期47卷 32-38页

作者： WANG Keli CHENG Guodong XIAO Honglang JIANG Hao Cold and Arid Regions environmental and Engineering research institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

The westerly fluctuation and the atmospheric water vapor transport over the Qilian-Heihe valley are analyzed and the results show that, in the water vapor transport stream field from Jun to September, this valley is in the westerly stream and the water vapor comes from westerlies water transport via the Black Sea and the Caspian Sea. The net water vapor transport is less net import and different from most areas of the northwest China. The interannual changes in water vapor transport over the valley arise from the westerly fluctuation, and have a positive relationship to the interannual changes in westerly wind speed. The cold air actions from the Mongol low pressure are the primary system that controls the westerly water vapor transport. Its action chain is that, the Mongol low pressure is strengthened → the circulation meridionality will be increased → the cold air will move southwards → the westerly will be stronger → the wind convergence of direction and speed will be stronger → the water vapor convergence transport will be increased → the local water vapor content will be increased. The interannual changes in atmospheric water vapor transport over the valley rely mainly on the convergence transport, but the effect of advection transport is less. The interannual changes of strong or weak westerly affect mainly the convergence transport, and then make the atmospheric water vapor net transport increase or decrease over the Qilian-Heihe valley.

关键词： waler vapor transport westerly fluctuation Qilian-Heihe valley northwest China water resource.

Impacts of Global Warming on Hydrological Cycles in the Asian Monsoon Region

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Advances in Atmospheric Sciences 2008年第6期25卷 960-973页

作者： Koji DAIRAKU Seita EMORI Toru NOZAWA Storm Flood and Landslide Research Department National Research Institute for Earth Science and Disaster Prevention Climate Risk Assessment research Section Center for Global Environmental Research National Institute for Environmental Studies Atmospheric Physics Section Atmospheric Environment Division National Institute for Environmental Studies

The hydrologic changes and the impact of these changes constitute a fundamental global-warmingrelated concern. Faced with threats to human life and natural ecosystems, such as droughts, floods, and soil erosion, water resource planners must increasingly make future risk assessments. Though hydrological predictions associated with the global climate change are already being performed, mainly through the use of GCMs, coarse spatial resolutions and uncertain physical processes limit the representation of terrestrial water/energy interactions and the variability in such systems as the Asian monsoon. Despite numerous studies, the regional responses of hydrologic changes resulting from climate change remains inconclusive. In this paper, an attempt at dynamical downsealing of future hydrologic projection under global climate change in Asia is addressed. The authors conducted present and future Asian regional climate simulations which were nested in the results of Atmospheric General Circulation Model （AGCM） experiments. The regional climate model could capture the general simulated features of the AGCM. Also, some regional phenomena such as orographic precipitation, which did not appear in the outcome of the AGCM simulation, were successfully produced. Under global warming, the increase of water vapor associated with the warmed air temperature was projected. It was projected to bring more abundant water vapor to the southern portions of India and the Bay of Bengal, and to enhance precipitation especially over the mountainous regions, the western part of India and the southern edge of the Tibetan Plateau. As a result of the changes in the synoptic flow patterns and precipitation under global warming, the increases of annual mean precipitation and surface runoff were projected in many regions of Asia. However, both the positive and negative changes of seasonal surface runoff were projected in some regions which will increase the flood risk and cause a mismatch between water

关键词： hydrologic change dynamical downscaling regional climate model Asian monsoon region

PM_(2.5) in an industrial district of Zhengzhou,China:Chemical composition and source apportionment

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Particuology 2013年第1期11卷 99-109页

作者： Ningbo Geng Jia Wang Yifei Xu Wending Zhang Chun Chen Ruiqin Zhang research institute of environmental Science Department of ChemistryZhengzhou University Henan environmental Monitoring Center

Zhengzhou is a developing city in China, that is heavily polluted by high levels of particulate matter. In this study, fine particulate matter （PM2.5） was collected and analyzed for their chemical composition （soluble ions, elements, elemental carbon （EC） and organic carbon （OC）） in an industrial district of Zhengzhou in 2010. The average concentrations of PM2.5 were 181, 122, 186 and 211 μg/m3 for spring, summer, autumn and winter, respectively, with an annual average of 175 μg/m3, far exceeding the PM2.5 regulation of usA National Air Quality Standards （15 μg/m3）. The dominant components of PM2.5 in Zhengzhou were secondary ions （sulphate and nitrate） and carbon fractions. Soluble ions, total carbon and elements contributed 41%, 13% and 3% of PM2.5 mass, respectively. Soil dust, secondary aerosol and coal combustion, each contributing about 26%, 24% and 23% of total PM2.5 mass, were the major sources of PM2.5, according to the result of positive matrix factorization analysis. A mixed source of biomass burning, oil combustion and incineration contributed 13% of PM2.5. Fine particulate matter arising from vehicles and industry contributed about 10% and 4% of PM2.5, respectively.

关键词： PM2.5 Component Seasonal variation PMF Source apportionment

Preferential oxidation of CO in excess H_2 over CeO_2/CuO catalyst:Effect of calcination temperature

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Journal of Natural Gas Chemistry 2012年第5期21卷 513-518页

作者： Zhiming Gao Ming Zhou Hao Deng Yong Yue Key Laboratory of Cluster Science Ministry of Education of China School of Chemistry Beijing Institute of TechnologyBeijing 100081China research Department of environmental Technology CNPC Research Institute of Safety and Environmental TechnologyBeijing 100083China

Different from the classical configuration CuO/CeO2 catalyst,the inverse configuration CeO2 /CuO catalyst （atomic ratio of Ce/Cu=10/100） was prepared by impregnation *** calcination temperatures were selected to investigate the interaction between CeO2 and CuO *** is found that as calcination temperature increased from 500 to 900 C,sintering of CeO2 particles on the support occurred together with the diffusion of a portion of Ce 4＋ ions into CuO crystals,forming solid *** of interface complex Ce-O-Cu was suggested by TPR *** catalyst calcined at 700 C gives the highest activity for preferential oxidation of CO in excess H2 stream.

关键词： preferential oxidation carbon monoxide cerium oxide cupric oxide TPR

Seasonal exports of phosphorus from intensively fertilised nested grassland catchments

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Journal of environmental Sciences 2013年第9期25卷 1847-1857页

作者： Ciaran Lewis Rashad Rafique Nelius Foley Paul Leahy Gerard Morgan John Albertson Sandeep Kumar Gerard Kiely Department of Civil and environmental Engineering University College Cork Department of Microbiology and Plant Biology University of Oklahoma environmental research institute University College Cork Aquatic Services Unit Environmental Research Institute University College Cork Department of Civil and environmental Engineering Duke University Department of Plant Science South Dakota State University

We carried out a one year （2002） study of phosphorus （P） loss from soil to water in three nested grassland catchments with known P input in chemical fertilizer and animal liquid slurry applications. Chemical fertilizer was applied to the grasslands between March and September and animal slurry was applied over the twelve months. The annual chemical P fertilizer applications for the 17 and 211 ha catchments were 16.4 and 23.7 kg P/ha respectively and the annual slurry applications were 10.7 and 14.0 kg P/ha, respectively. The annual total phosphorus （TP） export in stream-flow was 2.61, 2.48 and 1.61 kg P/ha for the 17, 211 and 1524 ha catchments, respectively, compared with a maximum permissible （by regulation） annual export of ca. 0.35 kg P/ha. The export rate （ratio of P export to P in land applications） was 9.6% and 6.6% from the 17 and 211 ha catchments, respectively. On average, 70% of stream flow and 85% of the P export occurred during the five wet months （October to February） indicating that when precipitation is much greater than evaporation, the hydrological conditions are most favourable for P export. However the soil quality and land use history may vary the results. Particulate P made up 22%, 43% and 37% of the TP export at the 17, 211 and 1524 ha catchment areas, respectively. As the chemical fertilizer was spread during the grass growth months （March to September）, it has less immediate impact on stream water quality than the slurry applications. We also show that as the catchment scale increases, the P concentrations and P export decrease, confirming dilution due to increasing rural catchment size. In the longer term, the excess P from fertilizer maintains high soil P levels, an antecedent condition favourable to P loss from soil to water. This study confirms the significant negative water quality impact of excess P applications, particularly liquid animal slurry applications in wet winter months. The findings suggest that restricted P application in w

关键词： phosphorus fertilizer slurry exports grassland land management water quality eutrophication

research Progress on the Corrosion Behavior of Magnesium-Lithium-Based Alloys: A Review

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Acta Metallurgica Sinica(English Letters) 2019年第1期32卷 1-9页

作者： Bao-Jie Wang Ji-Yu Luan Dao-Kui Xu Jie Sun Chuan-Qiang Li En-Hou Han School of environmental and Chemical Engineering Shenyang Ligong University Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal Research Chinese Academy of Sciences environmental Corrosion Center Institute of Metal ResearchChinese Academy of Sciences

In this review paper, the research progress on corrosion behavior of hexagonal close-packed(HCP) singular phase, body cubic-centered(BCC) singular phase and(HCP + BCC) duplex-structured Mg–Li alloys has been summarized and reviewed, and the future trend about the studies on corrosion behavior of Mg–Li-based alloys and possible solving methods for the improvement in corrosion resistance are discussed also.

关键词： Magnesium–lithium alloys Crystallographic structure Corrosion behavior Corrosion product film Corrosion mechanism

Carbon assimilation characteristics of plants in oasis-desert ecotone and their response to CO_2 enrichment

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Science China Earth Sciences 2004年第z1期47卷 39-49页

作者： SU Peixi CHEN Huaishun AN Lizhe LIU Xinmin Cold and Arid Regions environmental and Engineering research institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China Cold and Arid Regions Environmental and Engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Six species of more than 20-year-old desert woody plants in the oasis-desert ecotone were selected for study. The results showed that: (1) in different growing seasons δ13C values of assimilating organ varied between -14‰ and -16‰ for Haloxylon ammodendron (HA),-14‰-15‰ for Calligonum mongolicum (CM) and-25‰- -28‰ for Caragana korshinskii(CK), Nitraria sphaerocarpa (NS) and Hedysarum scoparium (HS). (2) The net photosynthetic rate (Pn) of HA and CM was significantly higher than those of the other species. With the decrease in Pn for the six species, their intercellular CO2 concentration increased, but stomatal limitation value decreased under the intensive light. At the same time, the photochemical efficiency of PS II dropped to different degrees. (3) The CO2 enrichment experiment demonstrated that, Pn of HA and CM increased to different extent under 450 umol/mol, but their Pn reduced or approximated to the current condition under 650 umol/mol. Under 450 umol/mol the efficiency for solar energy utilization of CK and HS significantly reduced and under 650 umol/mol their respiration rate exceeded photosynthesis rate. It can be concluded that HA and CM have some function of pathway for C4, but the other three species have the function for C3. The decline in their Pn is mainly caused by non-stomatal factors. HA, CM, CKand HS exhibited photoinhibition, which disappeared in a short time. This is a kind of positive readjustment to adapting to the desert environment. HA and CM can adapt to the high CO2 environment, but CK and HS cannot. With the rise in atmospheric CO2 concentration and climate warming, the latter two species in the oasis-desert ecotone may be gradually degraded or even disappear.

关键词： oasis-desert ecotone, carbon assimilation, stable carbon isotope ratio, photoinhibition, CO2 enrichment.

Diapause development in early and late emerging phenotypes of Delia floralis

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Insect Science 2014年第1期21卷 103-113页

作者： Tor J. Johansen Richard Meadow Arctic Agriculture and Land use Division Bioforsk - Norwegian Institute for Agricultural and Environmental Research Tromsm plant Health and Plant Protection Division Bioforsk - Norwegian Institute for Agricultural and Environmental Research As Norway

The turnip fly, Delia floralis Fall6n （Diptera： Anthomyiidae） is an important insect pest of brassica vegetable crops in the holarctic region. Different populations have strongly varying temperature requirements for fly emergence, a challenge for accurate prediction of activity. This study focused on diapause development in one early and one late emerging phenotype. The physiological state after various treatments was deduced from emergence data. Our results showed a slow diapause progression at chilling conditions for both populations and diapause ended about 7 months after pupae were formed for the early population. For the late population held at 4℃ diapause did not end, no matter how long the duration of chilling. These pupae required a period with elevated temperatures above 6~C to continue development. At constant non-chilling conditions （18℃） from the time pupae were formed both populations completed diapause most rapidly. These results indicate that chilling delayed, rather than accelerated development and was not a prerequisite for diapause development. For post-diapause, results indicated a linear relationship between rate of development and temperature within the range of 6-18℃and a theoretical base temperature for development of about 2℃ for both populations. In conclusion, D. floralis pupae are in diapause throughout a long winter period, and delayed emergence of the late population appears to be caused by prolonged diapause regulated by a developmental temperature threshold. The study has added information on the biology of turnip fly populations, a prerequisite for improved pest control.

关键词： brassica chilling emergence hibernation quiescence