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371.
This paper analyzes the air quality impacts of coal-fired power plants in the northern passageway of the West-East Power Transmission Project in China. A three-layer Lagrangian model called ATMOS, was used to simulate the spatial distribution of incremental sulfur dioxide (SO2) and coarse particulate matter (PM10) concentrations under different emission control scenarios. In the year 2005, the emissions from planned power plants mainly affected the air quality of Shanxi, Shaanxi, the common boundary of Inner Mongolia and Shanxi, and the area around the boundary between Inner Mongolia and Ningxia. In these areas, the annually averaged incremental SO2 and PM10 concentrations exceed 2 and 2.5 microg/m3, respectively. The maximum increases of the annually averaged SO2 and PM10 concentrations are 8.3 and 7.2 microg/m3, respectively, which occur around Hancheng city, near the boundary of the Shaanxi and Shanxi provinces. After integrated control measures are considered, the maximum increases of annually averaged SO2 and PM10 concentrations fall to 4.9 and 4 microg/m3, respectively. In the year 2010, the areas affected by planned power plants are mainly North Shaanxi, North Ningxia, and Northwest Shanxi. The maximum increases of the annually averaged SO2 and PM10, concentrations are, respectively, 6.3 and 5.6 microg/m3, occurring in Northwest Shanxi, which decline to 4.4 and 4.1 microg/m3 after the control measures are implemented. The results showed that the proposed power plants mainly affect the air quality of the region where the power plants are built, with little impact on East China where the electricity will be used. The influences of planned power plants on air quality will be decreased greatly by implementing integrated control measures.  相似文献   
372.
钻井废液的超临界水氧化处理及动力学分析   总被引:2,自引:0,他引:2  
在反应温度为500~600℃、压力为25~30 MPa、停留时间为30~600 s的条件下,在连续式反应器中研究了钻井废液的超临界水氧化反应.结果表明:钻井废液的COD去除率可达90.00%以上;在600℃、停留时间为600 s时,钻井废液氧化后,剩余收集液的COD<120 mg/L,满足《污水综合排放标准》(GB 8978-1996)中的二级标准.用幂函数方程描述了氧化剂过量时钻井废液超临界水氧化的反应动力学规律,反应速率常数与温度的关系符合Arrhenius公式,随停留时间的增加、温度的升高,有机物的去除率显著增加;反应速率常数随压力升高而增加,但反应速率常数的增幅随压力的升高而减小,反应活化体积不是常数.在25 MPa时,反应活化能和频率因子分别为(17 745.430 40±1 114.983 42)kJ/mol和1.152 3×10-4s-1模型计算值与实验值的误差在±15%以内.  相似文献   
373.
本文对我国苏铁属植物分布、资源现状、植物濒危原因进行了初步考察和研究,提出了苏铁植物保护的四点建议。  相似文献   
374.
北京市大气中多氯联苯的污染水平和分布特征   总被引:1,自引:0,他引:1  
利用XAD树脂被动采样技术和同位素稀释高分辨气相色谱/高分辨质谱联用法(HRGC/HRMS)研究了2012年11月至2014年1月北京地区大气中多氯联苯(PCBs)的污染现状、区域分布特征及季节性变化规律.结果表明,北京大气中19种PCBs总浓度为8.42—45.2 pg·m-3(平均值23.1 pg·m-3),各采样点全年平均毒性当量范围为0.33—3.33 fg WHO-TEQ m-3(平均值1.85 fg WHO-TEQ m-3).PCB-11浓度范围为27.9—136pg·m-3,平均值为78.2 pg·m-3.大气中的PCBs以低氯代(2—5氯代)PCBs为主.季节变化规律呈现出夏/秋季节PCBs浓度高于冬/春季节的规律;区域分布特征呈现出人口密集的城区大于背景区、工业区大于城区的规律.  相似文献   
375.
Congestion causes many externalities for the society, including time delays, excessive fuel consumption, air pollution, noise and safety concerns. In Shanghai, various policy options have been explored, piloted or applied; however, not all of them may be understood and accepted by the public. A survey was conducted to investigate people's attitudes towards several policy options. The main findings reveal that Shanghai residents are resistant to certain policies, such as congestion charges, higher parking charges in congested areas and car restrictions. Instead, they favor public transport provisions. The paper suggests that there is a case for promoting public transport and more efficient trips when the car ownership is still low, and for investing in a policy of educating the public on the 'true' costs and causes of congestion before embarking on ,an intensive policy of congestion charges or restrictions.  相似文献   
376.
The national ‘Shandong Peninsula Blue Economic Zone Development Plan’ compels the further understanding of the distribution and potential risk of metals pollution in the east coast of China, where the rapid economic and urban development have been taken off and metal pollution has become a noticeable problem. Surface sediments collected from the largest swan habitat in Asia, the Swan Lake lagoon and the surrounding coastal area in Rongcheng Bay in northern Yellow Sea, were analyzed for the total metal concentrations and chemical phase partitioning of five heavy metals (Cu, Zn, Pb, Cd, and Cr). Metal contents in the studied region have increased significantly in the past decade. The speciation analyzed by the sequential extraction showed that Zn and Cr were present dominantly in the residual fraction and thus of low bioavailability, while Cd, Pb and Cu were found mostly in the non-residual fraction thus of high potential availability, indicating significant anthropogenic sources. Among the five metals, Cd is the most outstanding pollutant and presents high risk, and half of the surface sediments in the studied region had a 21% probability of toxicity based on the mean Effect Range-Median Quotient. At some stations with comparable total metal contents, remarkably different non-residual fraction portions were determined, pointing out that site-specific risk assessment integrating speciation is crucial for better management practices of coastal sediments.  相似文献   
377.
王永  马璞  宋文华 《安全》2009,30(8):13-16
本文简要介绍了事故树分析法和对偶成功树分析法的基本原理,利用对偶成功树分析法以某涂料生产企业车间可燃液体蒸气火灾爆炸事故为例,将建立的涂料生产企业车间可燃液体蒸气火灾爆炸事故树转化为对偶成功树,求得对偶成功树的最小径集,通过对最小径集中各基本事件结构重要度的比较,确定了结构重要度最高的基本事件。结合该企业的生产实际提出了确保车间可燃液体蒸气火灾爆炸事故不发生的火灾控制措施。  相似文献   
378.
At a stage of rapid economic development and urbanization in China, most cities are faced with serious problems caused by environment deterioration such as pollution, space press, afforestation degradation, and disordering. Kunshan City, one of the most economically vigorous regions in China, has suffered a more prominent conflict between urbanization and environmental safety. In this paper, urban land expansion in Kunshan City in the Yangtze River Delta was measured with reference to the Landsat data recorded in 1982, 1991, 1995, and 2003 and change in land-use pattern in 1981, 1991, 1995, and 2004 as well as that in nutrients in soils of different purposes between the periods were analyzed to study the effect of urban land-use expansion on soil characteristics. To get a better understanding of soil nutrients, heavy metal content, and pollution, on-the-spot investigation, sampling and laboratory analysis were all conducted, and the geo-accumulation factors and revised Nemerow comprehensive index method were adopted for evaluation of the findings. The results show that the content of organic matter, total nitrogen, rapidly available nitrogen, and available phosphorus in the soil (except available potassium) all increased, and the average content of As, Cd, Cr, Cu, Pb, Ni, Hg, Se, and Zn prove to be 8.61, 0.12, 83.53, 32.49, 29.93, 30.45, 0.27, 0.24, and 93.3 mg kg−1, respectively, showing degradation in soil quality.  相似文献   
379.
本文针对目前我国城市集中式污水处理方法的弊端,提出将小型人工湿地运用于城市小区的污水处理,实现环境目标与经济效益的结合。  相似文献   
380.
可持续发展与地球表层的进化   总被引:6,自引:0,他引:6  
包括非生物、生物和人的地球表层巨系统,是人的生存环境,它是进化发展的。人类社会只有认识并遵守地球表层的进化规律,才能达到可持续发展的目标。  相似文献   
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