首页 | 本学科首页   官方微博 | 高级检索  
文章检索
  按 检索   检索词:      
出版年份:   被引次数:   他引次数: 提示:输入*表示无穷大
  收费全文   44篇
  免费   4篇
安全科学   3篇
废物处理   2篇
环保管理   8篇
综合类   10篇
污染及防治   21篇
评价与监测   2篇
灾害及防治   2篇
  2024年   1篇
  2022年   2篇
  2021年   4篇
  2020年   1篇
  2019年   2篇
  2018年   1篇
  2017年   1篇
  2014年   2篇
  2013年   9篇
  2012年   2篇
  2011年   2篇
  2010年   1篇
  2009年   2篇
  2008年   2篇
  2007年   2篇
  2004年   1篇
  2003年   2篇
  2001年   2篇
  2000年   6篇
  1994年   1篇
  1988年   1篇
  1959年   1篇
排序方式: 共有48条查询结果,搜索用时 578 毫秒
21.
Data from the 1990 San Joaquin Valley Air Quality Study/Atmospheric Utility Signatures, Predictions, and Experiments (SJVAQS/AUSPEX) field program in California's San Joaquin Valley (SJV) suggest that both urban and rural areas would have difficulty meeting an 8-hr average O3 standard of 80 ppb. A conceptual model of O3 formation and accumulation in the SJV is formulated based on the chemical, meteorological, and tracer data from SJVAQS/AUSPEX. Two major phenomena appear to lead to high O3 concentrations in the SJV: (1) transport of O3 and precursors from upwind areas (primarily the San Francisco Bay Area, but also the Sacramento Valley) into the SJV, affecting the northern part of the valley, and (2) emissions of precursors, mixing, transport (including long-range transport), and atmospheric reactions within the SJV responsible for regional and urban-scale (e.g., down-wind of Fresno and Bakersfield) distributions of O3. Using this conceptual model, we then conduct a critical evaluation of the meteorological model and air quality model. Areas of model improvements and data needed to understand and properly simulate O3 formation in the SJV are highlighted.  相似文献   
22.
23.
24.
循环经济作为一种新的、科学的发展观,要求高等职业教育必须建立全新的适应循环经济发展的人才培养模式,在专业建设中凸显循环经济理念,用专业长负责制实现专业建设与社会需求的联通。以中国环境管理干部学院为例,以精品课建设为载体,从循环经济视角探讨了专业长负责制的推行,以及取得的成效。  相似文献   
25.
孙嘉  齐实  澎湃  黄媛  刘孝盈  杨爱民 《中国环境科学》2014,34(12):3242-3248
依据“源头—过程—末端”防控体系对13种常见的农村水资源保护措施进行分类,在此基础上,建立AHP评价模型,根据影响水资源保护措施适宜性的13个指标对各项措施进行适宜性评价.结果表明:污染物去除率、出水水质、建设成本及运行维护这4个因素具有较高权重值,应在实际运用中优先考虑.源头控制措施中保护性耕作与“一池三改”技术可以作为首选措施;在过程控制措施中,土地处理技术措施具有较好的适宜性;在选取末端处理措施的时候,必须优先考虑温度及建设成本的影响.  相似文献   
26.
The SARMAP air quality model, enhanced with aerosol modeling capability, and its associated components were developed to understand causes of ozone (O3) and particulate matter exceedances in the San Joaquin Valley of California. In order for this modeling system to gain increasing acceptance and use in guiding air quality management, it is important to assess how transportable this modeling system is across geographic domains. We describe the first application of the modeling system outside the "home" domain for which it was developed and evaluated. We have chosen the August 27-28, 1987, intensive monitoring period of the Southern California Air Quality Study to evaluate the performance of the modeling system and to assess its sensitivity to emission control options. The predicted surface concentrations of O3 and other gas-phase species were spatially and temporally correlated with measured data. The fractional normalized absolute error was 0.32 to 0.36 for O3, and somewhat larger for other species. The fractional normalized bias for O3 on August 27 and 28, 1987, was 0.02 to 0.04. The simulated PM2.5 mass and constituent species concentrations reproduced the magnitude and variability of the observed daytime concentrations at most locations; however, nighttime PM2.5 concentrations were overpredicted by the model. The model's response to emission control options was consistent with other models of the same genre.  相似文献   
27.
普通话与口才训练教学中应加强人文素质教育   总被引:1,自引:0,他引:1  
经济社会的飞速发展并没有带来人文精神的匹配升华,新生代大学生无法和社会历史融合最重要的原因就是人文素质教育的缺乏。应使普通话与口才训练成为大学生人文素质教育的有效载体和实践途径,输送给学生口语交际知识和人文素质的双重养分。  相似文献   
28.
朋辈群体是影响大学生思想形成和发展的重要因素。在大学生思想政治工作中构建朋辈教育体系,通过设立班主任导生、政治导生、心理辅导员等形式,依靠朋辈群体开展学生思想政治教育工作,是做好学生教育和管理工作的一个独特而有效的切入点。  相似文献   
29.
The results of a pilot study that was conducted to determine the total nitrogen removal by the reverse osmosis process are presented. The organic nitrogen removal rates are compared with removals observed from three full-scale reverse osmosis facilities and four pilot studies. The results of this analysis suggest that organic nitrogen removal is variable and that reverse osmosis may not consistently produce total nitrogen levels less than 1.0 mg/L without additional treatment. Three hypotheses to explain the variability in organic nitrogen removal in the different data sets are presented.  相似文献   
30.
首次将固体废弃物硅酸钙微粉用于焦化废水的预处理,通过静态和动态吸附实验评价了硅酸钙微粉对COD和NH3-N的去除效果。结果表明:对COD和NH3-N产生吸附作用的有效组分为硅酸钙微粉的水解产物H2SiO3电离产生的HSiO3-和SiO23-;pH通过影响硅酸钙微粉水解反应以及水解产物H2SiO3和有机物、NH3的电离反应来影响去除率。在进水pH=7.00、硅酸钙微粉投加量为170g/L、振荡时间为75min的条件下,静态吸附实验中COD和NH3-N的去除率分别达16.1%和27.1%;经直径为10mm、高度为300mm的硅酸钙吸附柱预处理,动态吸附实验中COD和NH3-N的去除率分别可达58.9%和35.9%。  相似文献   
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号