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211.
阐述了酸雨的形成和危害;监测了近3a来五华区降水pH值。结果:2004年共出现酸雨5次,占全年降水次数6.3%;2005年无酸雨;2006年共出现酸雨1次,占全年降水次数1.6%。提出了酸雨防治措施。  相似文献   
212.
室内甲醛污染的分析调查   总被引:29,自引:1,他引:29  
含有甲醛的树脂广泛应用于建材、绝热材料、家具及服装等方面 ,使得室内空气发生甲醛污染。通过对室内甲醛污染的调查 ,室内甲醛污染高于室外 ,污染比室外更可怕 ,应引起人们对室内甲醛污染的高度重视。  相似文献   
213.
TiO_2-Fenton试剂光氧化降解水中氯代有机物的研究   总被引:8,自引:0,他引:8  
探讨了在光 Fenton体系中引入催化剂TiO2 对几种氯代有机物的光氧化降解效果及其影响因素。试验结果表明 ,TiO2 Fenton试剂复合体系对CH2 ClCOOH的光解脱氯速率显著高于TiO2 和Fenton试剂体系 ,TiO2 对Fenton光氧化反应有较强的催化作用 ;溶液 pH值、铁离子浓度、氯代有机物组成和结构等因素对复合体系的光氧化效果均有明显的影响  相似文献   
214.
以2001-2003年巢湖监测数据为依据,采用因子分析、聚类分析方法的复合模型进行计算,结果表明:2001-2003年间,影响巢湖水质的污染因子发生了改变,同时定量诊断出水污染因子对巢湖水质的贡献率,合理划分出各类水环境管理区域,并提出相应的水环境管理措施.在巢湖水环境管理分区中,可以大体分为2大类,在各类中可以再细分为几小类,西半巢湖属于重污染,为水环境控制区域,东半巢湖污染相对较轻,为水环境控制和自净区域.结果分析表明,复合模型具有一定的可靠性和准确性,具有一定的参考实用价值.  相似文献   
215.
INTENTION, GOAL, SCOPE, BACKGROUND: As the strong negative health effect of exposure to the inhalable particulate matter PM10 in the urban environment has been confirmed, the study of the mass concentrations, physico-chemical characteristics, sources, as well as spatial and temporal variation of atmospheric aerosol particles becomes very important. OBJECTIVE: This work is a pilot study to assess the concentration level of ambient suspended particulate matter, with an aerodynamic diameter of less than 10 microm, in the Belgrade central urban area. Average daily concentrations of PM10 and PM2.5 have been measured at three representative points in the city between June 2002 and December 2002. The influence of meteorological parameters on PM10 and PM2.5 concentrations was analyzed, and possible pollution sources were identified. METHODS: Suspended particles were collected on Pure Teflon filters by using a Mini-Vol low-volume air sampler (Airmetrics Co., Inc.; 5 l min(-1) flow rate). Particle mass was determined gravimetrically after 48 h of conditioning in a desiccator, in a Class 100 clean room at the temperature T = 20 degrees C and at about 50% constant relative humidity (RH). RESULTS AND DISCUSSION: Analysis of the PM10 data indicated a marked difference between season without heating--(summer; mean value 56 microg m(-3)) and heating season--(winter; mean value 96 microg m3); 62% of samples exceeded the level of 50 microg m(-3). The impact of meteorological factors on PM concentrations was not immediately apparent, but there was a significant negative correlation with the wind speed. CONCLUSIONS: The PM10 and PM2.5 mass concentrations in the Belgrade urban area had high average values (77 microg m(-3) and 61 microg m(-3)) in comparison with other European cities. The main sources of particulate matter were traffic emission, road dust resuspension, and individual heating emissions. When the air masses are coming from the SW direction, the contribution from the Obrenovac power plants is evident. During days of exceptionally severe pollution, in both summer and winter periods, high production of secondary aerosols occurred, as can be seen from an increase in PM2.5 in respect to PM10 mass concentration. RECOMMENDATION AND OUTLOOK: The results obtained gave us the first impression of the concentration level of particulate matter, with an aerodynamic diameter of less than 10 microm, in the Belgrade ambient air. Due to measured high PM mass concentrations, it is obvious that it would be very difficult to meet the EU standards (EEC 1999) by 2010. It is necessary to continue with PM10 and PM2.5 sampling; and after comprehensive analysis which includes the results of chemical and physical characterization of particles, we will be able to recommend effective control measures in order to improve air quality in Belgrade.  相似文献   
216.
Investigations presented in this paper were aimed at defining the alterations of n-alkane composition in cases of oil-polluted alluvial sediments. Therefore, oil-polluted groundwater samples, taken in five different time intervals during a period of 28 months, were investigated. Samples of alluvial sediments were taken from two boreholes within an oil refinery at Pancevo, Yugoslavia. In both boreholes significant alterations with characteristic degradation of "oil" n-alkanes with no odd- or even-member predominance were observed, as well as subsequent synthesis of new ones with pronounced even-member predominance, and with maxima at C16 and C18. Since no additional contamination of boreholes was observed by analyses of steranes and triterpanes, the observed changes can only be attributed to microbial activity. It is assumed that for the degradation of oil n-alkanes, as well as for the synthesis of "new" n-alkanes, algae such as dinoflagellates are responsible. This assumption was confirmed by identification of n-alcohols with even-member predominance (C14–C20), by identification of cholesterol, as well as of n-fatty acids with even-member predominance (C14–C18) in the extract with n-alkane even-member predominance. Electronic Publication  相似文献   
217.
A lipid-transfer protein was isolated from a domestic cultivar of brewers barley grain, Hordeum vulgare. The presence of Cu (II), Pb (II), Cd (II) and Zn (II) ions in its structure and its ability to bind Hg (II) and Ni (II) ions is known. We investigated its ability to bind other metal ions by differential pulse polarography. Here we demonstrate that the lipid-transfer protein has an affinity to bind Co (II) and Pb (II) and has no affinity towards Cd (II), Cu (II), Zn (II) and Cr (III). These results suggest a new possible role of barley lipid-transfer protein for phytoextraction.Selected article from the Regional Symposium on Chemistry and Environment, Krusevac, Serbia, June 2003, organised by Dr. Branimir Jovancicevic  相似文献   
218.
一个国家或地区的作物生产是通过轮作进行的,某些地区存在耕地的弃耕现象。Wackernagel生态足迹方法没有考虑复种的影响,耕地类生态足迹核算结果实际是播种面积,而生态承载力核算得到的是耕地面积,因此,二者不具有可比性,生态足迹盈余核算存在逻辑性错误。从理论角度采用复种指数修正耕地类生态足迹,使核算结果为耕地面积,增强了生态足迹和生态承载力的可比性。用改进的生态足迹核算方法,分析了阜宁县区域生态经济系统1995~2003年的生态供需状况及发展能力变动趋势,采用生态足迹盈余强度评价区域可持续发展能力。1995~2003年,阜宁县人均生态足迹从1.120 7 hm2增加到2.434 0 hm2,人均生态承载力变化较小,人均生态赤字从0.815 3 hm2增加为2.017 2 hm2,发展能力由1.226 5增加为3.140 7,生态足迹盈余强度由-1.226 5增强为-0.495 7 hm2。基于改进的生态足迹核算方法得到的发展能力和人均GDP之间的相关系数大于Wackernagel方法所得结果,表明改进的生态足迹方法能更好地反映区域社会经济状况。  相似文献   
219.
指出了环境污染纠纷的行政调解不同于行政处罚,一般性地阐述了行政调解的原则。  相似文献   
220.
从可持续度模型的特点出发,分析影响干旱区可持续发展的重要因子,对原先较适用于工业发达,环境污染严重的大中小型城市的区域PRED系统模式进行了改进。针对西部干旱区特殊的地理环境和经济结构,将水资源总量和生态环境因子引入可持续度模型。结合干旱区的实际情况和已有模型,选用人口增长、经济发展、发展阶段、水资源总量和生态环境这五大因子建立新的模型。将其应用于新疆和田民丰县,根据其波动规律将民丰县可持续发展变化分为五个阶段。  相似文献   
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