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我国南北方城市空气环境质量对比分析 总被引:2,自引:0,他引:2
依据国家环境监测部门公布的空气环境质量日报,对27个省会城市、4个直辖市城市的2004年-2006年空气质量数据进行分析。结果显示:我国城市空气污染指数(API)时空差异明显,冬、春季节API值高于夏季和秋季,北方城市的API均值高于南方城市;PM10是大气环境的主要污染物,作为首要污染物出现所占比例南、北方城市分别是66.64%和83.97%;SO2为首要污染物所占比例南、北方城市分别是7.28%和6.19%;北方城市平均Ⅰ级和Ⅱ级天数所占百分比之和为77.00%,重污染级天数所占比例达到1.02%;南方城市平均Ⅰ级和Ⅱ级天数所占百分比之和为87.24%,重污染天数所占百分比是0.04%;城市空气质量优、良天数呈增加趋势。 相似文献
534.
试验了玻璃、聚乙烯、聚四氟乙烯等不同材质容器溶出氯离子对环境空气中氯化氢测定的影响,指出测定结果偏高的原因在于采用玻璃气泡吸收管,分析了玻璃材质溶出氯离子的原因,建议采用特制的聚四氟乙烯或聚乙烯吸收管采样。 相似文献
535.
Hua Wang Yun Zhu Carey Jang Che-Jen Lin Shuxiao Wang Joshua S. Fu Jian Gao Shuang Deng Junping Xie Dian Ding Xuezhen Qiu Shicheng Long 《环境科学学报(英文版)》2015
Due to the increasingly stringent standards, it is important to assess whether the proposed emission reduction will result in ambient concentrations that meet the standards. The Software for Model Attainment Test—Community Edition (SMAT-CE) is developed for demonstrating attainment of air quality standards of O3 and PM2.5. SMAT-CE improves computational efficiency and provides a number of advanced visualization and analytical functionalities on an integrated GIS platform. SMAT-CE incorporates historical measurements of air quality parameters and simulated air pollutant concentrations under a number of emission inventory scenarios to project the level of compliance to air quality standards in a targeted future year. An application case study of the software based on the U.S. National Ambient Air Quality Standards (NAAQS) shows that SMAT-CE is capable of demonstrating the air quality attainment of annual PM2.5 and 8-hour O3 for a proposed emission control policy. 相似文献
536.
活性炭石英砂双层深床滤料浮滤池处理高藻水源水的研究 总被引:8,自引:0,他引:8
活性炭石英砂双层深床滤料浮滤池是一种采用气浮过滤一体化,活性炭石英砂双层深床过滤,常规处理和深度处理一体化的工艺.该工艺处理高藻原水的结果显示:出水藻总数为4.30×105个/L,总去除率为95.1%;出水叶绿素-a为0.88μg/L,总去除率为92.2%;出水浊度为0.18NTU;出水UV254为0.016cm-1,总去除率为54.3%;出水耗氧量为0.78mg/L,总去除率为63.6%,出水没有嗅味,色度为3度,总去除率为86.4%.出水残留铝含量为0.011mg/L,满足饮用水水质标准.过滤单元运行周期为36h,滤柱产水能力UFRV为504m3/m2. 相似文献
537.
A heuristic optimization approach for Air Quality Monitoring Network design with the simultaneous consideration of multiple pollutants 总被引:3,自引:0,他引:3
Elkamel A Fatehifar E Taheri M Al-Rashidi MS Lohi A 《Journal of environmental management》2008,88(3):507-516
An interactive optimization methodology for allocating the number and configuration of an Air Quality Monitoring Network (AQMN) in a vast area to identify the impact of multiple pollutants is described. A mathematical model based on the multiple cell approach (MCA) was used to create monthly spatial distributions for the concentrations of the pollutants emitted from different emission sources. These spatial temporal patterns were subject to a heuristic optimization algorithm to identify the optimal configuration of a monitoring network. The objective of the optimization is to provide maximum information about multi-pollutants (i.e., CO, NO(x) and SO(2)) emitted from each source within a given area. The model was applied to a network of existing refinery stacks and the results indicate that three stations can provide a total coverage of more than 70%. In addition, the effect of the spatial correlation coefficient (R(C)) on total area coverage was analyzed. The modeling results show that as the cutoff correlation coefficient R(C) is increased from 0.75 to 0.95, the number of monitoring stations required for total coverage is increased. A high R(C) based network may not necessarily cover the entire region, but the covered region will be well represented. A low R(C) based network, on the other hand, would offer more coverage of the region, but the covered region may not be satisfactorily represented. 相似文献
538.
腐蚀性环境与自动控制设备的保护 总被引:1,自引:0,他引:1
介绍了环境空气中腐蚀住气体对电子仪器和自动控制设备的腐蚀机理与防护方法.腐蚀产生的原因主要是直接氧化和电化学过程.腐蚀性环境通常根据腐蚀性气体的反应性进行分级.环境空气的腐蚀性可通过控制环境条件和空气净化去除。 相似文献
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Air pollution is one of the main factors that affect the air quality in aircraft cabins, and the use of different air supply modes could influence the distribution of air pollutants in cabins. Based on the traditional ceiling air supply mode used on the B737NG, this study investigated another 3 different kinds of air supply modes for comparison: luggage rack air supply mode, joint mode combining ceiling and luggage rack air supply, and joint mode combining ceiling and individual air supply. Under the above 4 air supply modes, the air velocity, temperature and distribution of air pollutants in a cabin full of passengers were studied using computational fluid dynamics (CFD), and carbon dioxide (CO2) and formaldehyde were selected as 2 kinds of representative air pollutants. The simulation results show that the joint mode combining ceiling and individual air supply can create a more uniform distribution of air velocity and temperature, has a better effect on the removal of CO2 and formaldehyde, and can provide better air quality in cabins than the other 3 modes. 相似文献