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Comparison of temporal and Spatial Characteristics of Ozone Pollution at Ground Level in the Eastern china

chinese Journal of Population,Resources and Environment 2006年第3期4卷 51-57页

作者： Liu Houfeng1,2.1. Shandong Normal University, Jinan 2.0014, china 2. chinese research academe of environmental sciences,{2. Shandong Normal University Jinan 250014 China chinese research {2. of environmental sciences Beijing 100012 China

Monitoring data from ozone（O3） automatic stations in three typical cities with different climatic areas in the southern and northern parts of eastern china are used to analyze temporal and spatial characteristics of ozone pollution at ground level. The results show that ozone pollution level has distinct regional differences and the concentration in the suburbs is higher than that in the urban areas. The seasonal variation of ozone concentration in different climatic areas is greatly affected by the variation of precipitation. Ozone concentration in Shenyang and beijing , in the temperate zone, has one perennial peak concentration, occurring in early summer, May or June. Ozone concentration in Guangzhou, in sub-tropical zone, has two peak values year round. The highest values occur in October and the secondary high value in June. The ozone season in the south is longer than that in the north. The annual average daily peak value of ozone concentrations in different climates usually occur around 3 pm. The diurnal variation range of ozone concentration declines with the increase of latitude. Ozone concentration does not elevate with the increase of traffic flow. Ozone concentration in Guangzhou has a distinct reverse relation to CO and NOx. This complicated non-linearity indicates that the equilibrium of ozone photochemical reaction has regional differences. Exceeding the rate of beijing＇s lh ozone concentration is higher than that of Guangzhou, whereas the average 8h ozone level is lower than that of Guangzhou, indicating that areas in low latitude are more easily affected by moderate ozone concentrations and longer exposure. Thus, china should work out standards for 8h ozone concentration.

关键词： ozone temporal and spatial characteristics 8h concentrations weekly variation

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Emission of landfill gas in Qingdao, china

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Journal of environmental sciences 1996年第3期8卷 292-297页

作者： Gao Jixi Shen Yingwa Cao Hongfa Shu Jianmin(Institute of Ecology, chinese research Academy of {2. sciences,beijing 100012. china) Institute of Ecology Chinese Res. Acad. of Environ. Sci. Beijing 100012 China

A study on landfill gas emission in Qingdao,china was carried out. The results showed that the generation of landfill gas with maximum methane concentration occurred several months after the refuse was disposed and the steady emission of landfill gas could remain two *** variation of landfill gas production was associated with temperature. In June, the emission of landfill gas rose gradually from morning to evening, but in September, it rose in the morning, and then fell in the afternoon. From June to August, the emission of landfill gas showed rising trend,but it declined quite quickly from September to December. In different seasons,the outflow rate of landfill gas varied from depth to depth in the refuse site. When earth temperature was higher in summer, the emission of landfill gas did not correspond with the depth of refuse sites, but when temperature fell in winter, and the temperature became a limited factor to the gas production,the outflow of landfill gas increased with increasing in depth of refuse piling.

关键词： landfill gas emission china

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Effect of external and internal phosphate status on arsenic toxicity and accumulation in rice seedlings

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Journal of environmental sciences 2009年第3期21卷 346-351页

作者： WANG Lihong,DUAN Guilan research Center for Eco-environmental {2.,chinese Academy of {2.,beijing 100085,china [a]research Center for Eco-environmental {2. Chinese Academy of Sciences Beijing 100085 China

Phosphorus （P） deficiency is thought to exacerbate the arsenic （As） phytotoxicity in paddy rice. The experiments were conducted to investigate the effects of external phosphate supply on As accumulation in rice and its toxicity under phosphate deficiency conditions. Rice seedlings pretreated with a phosphorus deficient nutrient solution （-P） for 14 d accumulated more As than those pretreated with a normal phosphorus supply nutrient solution （＋P）. Rice protreated with -P showed As toxicity symptoms after being exposed to 50 μmol/L arsenate for 4 h, while ＋P rice did not show any toxicity symptoms. Arsenic toxicity symptoms can be alleviated by increasing external P concentrations. The arsenate uptake rate and accumulation corresponded with the As toxicity in rice plants. Arsenic concentrations in rice roots decreased with increasing external phosphate concentrations. The lowest As accumulation and the highest P accumulation were found when the external P concentration reached 100μmol/L. In short, P deficiency increased the sensitivity of rice to arsenate and increasing of external phosphate supply could alleviate As toxicity.

关键词： phosphorus arsenate arsenic toxicity arsenic accumulation rice seedlings

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Current status and future of acid rain in china

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chinese Science Bulletin 1997年第24期42卷 2076-2081页

作者： DING Guo’an, XU Xiaobing, FANG Xiumei, JIN Shaping, XU Xia, Tang Jie, LIU Qijun, WANG Shufeng and WANG Wenxing1. chinese Academy of Meteorological sciences, {2. 100081, china 2. chinese Academy of Environment sciences, beijing 100012. china chinese Academy of Meteorological sciences Beijing 100081 China

As a part of the national key project of acid rain research, chemical element analysis of rainwater has been carried out based on observation of acid rain network in chinese MeteorologicalAdministration over the years of 1992.and 1993. Samples of precipitation collected from eachacid rain station were taken according to the standard established by chinese MeteorologicalAdministration. pH value was measured with pH meter (accuracy of 0. 01) made in

关键词： acid rain current status future.

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Ionization state of cosmic hydrogen by early stars and quasars

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research in Astronomy and Astrophysics 2009年第6期9卷 665-681页

作者： Xiao-Chun Mao1,2.1 National Astronomical Observatories, chinese Academy of sciences,{2. 2.Graduate University of chinese Academy of sciences, beijing 100049, china National Astronomical Observatories Chinese Academy of Sciences Beijing 100012 China Graduate University of chinese Academy of sciences Beijing 100049 China

Cosmic hydrogen is reionized and maintained in its highly ionized state by the ultraviolet emission attributed to an early generation of stars and quasars. The Lyα opacity observed in absorption spectra of high-redshift quasars permits more stringent constraints on the ionization state of cosmic hydrogen. Based on density perturbation and structure formation theory, we develop an analytic model to trace the evolution of the ionization state in the post-overlap epoch of reionization, in which the bias factor is taken into account. For quasars, we represent an improved luminosity function by utilizing a hybrid approach for the halo formation rate that is in reasonable agreement with the published measurements at 2.≤ z ≤ 6. Comparison with the classic Press-Schechter mass function of dark matter halos, we demonstrate that the biased mass distribution indeed enhances star formation efficiency in the overdense environment by more than 2. per cent following the overlap of ionized bubbles. In addition, an alternative way is introduced to derive robust estimates of the mean free path for ionizing photons. In our model, star-forming galaxies are likely to dominate the ionizing background radiation beyond z = 3, and quasars contribute equally above a redshift of z ～ 2.5. From 5 ≤ z ≤ 6, the lack of evolution in photoionization rate can thus be explained by the relatively flat evolution in star formation efficiency, although the mean free path of ionizing photons increases rapidly. Moreover, in the redshift interval z ～ 2.- 6, the expected mean free path and Gunn-Peterson optical depth obviously evolve by a factor of ～ 500 and ～50 respectively. We find that the relative values of critical overdensities for hydrogen ionization and collapse could be 430% at z ≈2.and 2. at z ≈6, suggesting a rapid overlap process in the overdense regions around instant quasars following reionization. We further illustrate that the absolute estimates of the fraction of neutral hydrogen computed fr

关键词： cosmology theory -- formation galaxies -- quasars general -- diffuse radiation -- intergalactic medium

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Preparation and characterization of a novel adsorbent for removing lipophilic organic from water

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Science china Chemistry 2005年第6期48卷 600-604页

作者： LIU Huijuan1, DAI Ruihua1, QU Jiuhui1 & RU Jia1,2.1. State Key Laboratory of environmental Aquatic Chemistry, research Center for Eco-environmental sciences, chinese Academy of sciences, beijing 100085, china 2. Graduate School of the chinese Academy of sciences, beijing 100039, china 1. State Key Laboratory of environmental Aquatic Chemistry Research Center for Eco-Environmental Sciences Chinese Academy of Sciences 100085 Beijing China 2. Graduate School of the chinese Academy of sciences 100039 Beijing China

A novel composite adsorbent containing a kind of lipid-triolein is studied. The ad-sorbent is prepared by embedding triolein into cellulose acetate (CA) sphere. The preparation method, the physical-chemical properties of the adsorbent and the removal efficiency of two or-ganochlorinated pesticides are studied. The adsorbent is stable in water and no triolein leaks into water for 465 h soaking. The adsorbent has high adsorption capacity for organochlorinated pes-ticides such as dieldrin and aldrin. The results suggest that triolein-containing adsorbent could serve as a good adsorbent for lipophilic organic pollutants. The adsorption rate for lipophilic pol-lutants is very fast and has relation with the logKow of the compounds.

关键词： triolein, cellulose acetate, adsorbent, lipophilic organic, drinking water.

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Urbanization, environmental consequences and management in china

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Journal of environmental sciences 1995年第1期7卷 1-11页

作者： Lu Yonglong (research Center for Eco-environmental {2.),chinese Acaderny of Scieiences,beijing 100085,china) Sch Ctr for Eco-Envmtl Sci Chinese Acad of Sci Beijing China China

Ｕｒｂａｎｉｚａｔｉｏｎ，ｅｎｖｉｒｏｎｍｅｎｔａｌｃｏｎｓｅｑｕｅｎｃｅｓａｎｄｍａｎａｇｅｍｅｎｔｉｎＣｈｉｎａＬｕＹｏｎｇｌｏｎｇ（ＲｅｓｅａｒｃｈＣｅｎｔｅｒｆｏｒＥｃｏ－ＥｎｖｉｒｏｎｍｅｎｔａｌＳｃｉｅｎ... 详细信息

Ｕｒｂａｎｉｚａｔｉｏｎ，ｅｎｖｉｒｏｎｍｅｎｔａｌｃｏｎｓｅｑｕｅｎｃｅｓａｎｄｍａｎａｇｅｍｅｎｔｉｎＣｈｉｎａＬｕＹｏｎｇｌｏｎｇ（ＲｅｓｅａｒｃｈＣｅｎｔｅｒｆｏｒＥｃｏ－ＥｎｖｉｒｏｎｍｅｎｔａｌＳｃｉｅｎｃｅｓ），ＣｈｉｎｅｓｅＡｃａｄｅ...

关键词： urbanization environmental management urban ecological planning

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Cleaning method of the oil field wastewater treatment by UF process

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Journal of environmental sciences 2001年第3期13卷 365-367页

作者： WANG Jing rong, Xu Cheng(research Center for Eco environmental {2., chinese Academy of {2., beijing 100085, china) research Center for Eco-environmental {2. Chinese Academy of Sciences Beijing 100085 China.

This article introduces experiments and researches of polysulphone ultrafiltration membrane's effect on oil field polluted water and approaches renewing oil field polluted water and approaches renewing of membrane's flux by different detergents and cleaning method. Good result has been achieved by doing experiments and the renewal rate of membrane is over 90%.

关键词： Detergents Membranes Oil fields Ultrafiltration Water pollution

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Combined toxicity of copper and cadmium to six rice genotypes (Oryza sativa L.)

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Journal of environmental sciences 2009年第5期21卷 647-653页

作者： HUANG Yizong, HU Ying, LIU Yunxia research Center for Eco-environmental {2., chinese Academy of {2., beijing 100085, china. [a]research Center for Eco-environmental {2. Chinese Academy of Sciences Beijing 100085 China

Accumulations of copper （Cu） and cadmium （Cd） in six rice cultivars （94D-2., 94D-54, 94D-64, Gui630, YY-1, and KY1360） were evaluated through exposure to heavy metal contamination （100 mg/kg Cu, 1.0 mg/kg Cd, and 100 mg/kg Cu ＋ 1.0 mg/kg Cd） in a greenhouse. The dry weights of shoot and root, concentrations of Cu and Cd in plant tissues and the Cu, Cd, P, Fe concentrations in the root surface iron plaques were analyzed eight weeks later after treatment. The results indicated that the plant biomass was mainly determined by rice genotypes, not Cu and Cd content in soil. Separated treatment with Cu/Cd increased each metal level in shoot, root and iron plaques. Soil Cu enhanced Cd accumulation in tissues. In contrast, Cu concentrations in shoot and root was unaffected by soil Cd. Compared to single metal contamination, combined treatment increased Cd content by 110.6%, 77.0%, and 45.2. in shoot, and by 112.7%, 51.2. and 18.4% in root for Gui630, YY-1, and KY1360, respectively. The content level of Cu or Cd in root surface iron plaques was not affected by their soil content. Cu promoted Fe accumulation in iron plaques, while Cd has no effect on P and Fe accumulation in it. The translocation of Cu and Cd from iron plaques to root and shoot was also discussed. These results might be beneficial in selecting cultivars with low heavy metal accumulation and designing strategies for soil bioremediation.

关键词： Cu Cd combined contamination soil uptake accumulation root surface iron plaques

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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 {2., chinese Academy of {2., beijing 100085, china. research Center for Eco-environmental {2. 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 2.0 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

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