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   8731篇
  免费   958篇
  国内免费   1420篇
安全科学   1921篇
废物处理   517篇
环保管理   1463篇
综合类   4173篇
基础理论   873篇
环境理论   9篇
污染及防治   611篇
评价与监测   488篇
社会与环境   642篇
灾害及防治   412篇
  2024年   36篇
  2023年   139篇
  2022年   263篇
  2021年   337篇
  2020年   323篇
  2019年   302篇
  2018年   286篇
  2017年   393篇
  2016年   431篇
  2015年   460篇
  2014年   442篇
  2013年   644篇
  2012年   728篇
  2011年   702篇
  2010年   533篇
  2009年   507篇
  2008年   357篇
  2007年   562篇
  2006年   606篇
  2005年   452篇
  2004年   340篇
  2003年   360篇
  2002年   325篇
  2001年   265篇
  2000年   250篇
  1999年   215篇
  1998年   138篇
  1997年   132篇
  1996年   127篇
  1995年   91篇
  1994年   73篇
  1993年   65篇
  1992年   44篇
  1991年   34篇
  1990年   31篇
  1989年   11篇
  1988年   12篇
  1987年   10篇
  1986年   7篇
  1983年   3篇
  1982年   8篇
  1981年   5篇
  1980年   12篇
  1979年   5篇
  1978年   8篇
  1977年   9篇
  1975年   6篇
  1973年   6篇
  1972年   3篇
  1971年   5篇
排序方式: 共有10000条查询结果,搜索用时 46 毫秒
941.
张国钧 《化工环保》1995,15(5):270-275
比较了胶布热空气连续硫化废气的几种处理方法,认为焚烧法是最有效的处理方法,并对应用该法处理废气的工艺原理、主要设备、余热回收是焚烧过程中诮注意的事项作了较详尽的阐述。  相似文献   
942.
刘自凤 《化工环保》1995,15(2):83-86
将含有大量悬浮物的洗气箱废水进行初级沉降后,约3/4的废水返回洗气箱用作洗涤水,其余的与洗气塔废水混合进地沉降池去除悬浮物,上清液送至生物滤池进行生化处理去除含氰人合物其他有机物。生化出水经絮凝、澄清后回用于洗气箱和洗气塔实现了废水闭路循环。他  相似文献   
943.
电解法处理高含硫气田水   总被引:1,自引:0,他引:1  
本文详细介绍了川南矿区含硫气田水电解法处理的试验情况,用自己研制的电解反应器对电解时间、pH值、电流密度等工艺条件进行了考察,提出了电解法处理含S~(2-)200mg/L的气田水的最佳工艺条件。试验结果表明:该方法是成功的,它可以使气田水中硫化物的脱除率达99%以上,达到国家排放标准(GB8978—88:S~(2-)<5mg/L)。该方法的主要特点是投加处理药剂少,操作简便,设备小型,占地面积小,特别适用于产水量不大的井站使用。  相似文献   
944.
ABSTRACT: Historically ephemeral washes in the Las Vegas Valley have become perennial streams in the urbanized area, and the primary source of these perennial flows appears to be the overirrigation of ornamental landscaping and turf. Overirrigation produces direct runoff to the washes via the streets and results in high ground water levels in some areas. Elevated ground water levels result in discharge to the washes because of changes in the natural balance of the hydrologic system and construction site and foundation dewatering. In recognition of the resource potential of these flows within the Las Vegas Valley, of the potential for dry weather flows to convey pollutants from the Valley to Lake Mead, and of the need to characterize dry weather flows under the stormwater discharge permit program, the quantity and quality of dry weather flow in Flamingo Wash was investigated during the period September 1990 through May 1993. This paper focuses on the resource potential of the flow (quantity and quality) as it relates to the interception and use of this water within the Valley. Economic and legal issues associated with the interception and use of this resource are not considered here.  相似文献   
945.
ABSTRACT: Stationarity of rainfall statistical parameters is a fundamental assumption in hydraulic infrastructure design that may not be valid in an era of changing climate. This study develops a framework for examining the potential impacts of future increases in short duration rainfall intensity on urban infrastructure and natural ecosystems of small watersheds and demonstrates this approach for the Mission/Wagg Creek watershed in British Columbia, Canada. Nonstationarities in rainfall records are first analyzed with linear regression analysis, and the detected trends are extrapolated to build potential future rainfall scenarios. The Storm Water Management Model (SWMM) is used to analyze the effects of increased rainfall intensity on design peak flows and to assess future drainage infrastructure capacity according to the derived scenarios. While the framework provided herein may be modified for cases in which more complex distributions for rainfall intensity are needed and more sophisticated stormwater management models are available, linear regressions and SWMM are commonly used in practice and are applicable for the Mission/Wagg Creek watershed. Potential future impacts on stream health are assessed using methods based on equivalent total impervious area. In terms of impacts on the drainage infrastructure, the results of this study indicate that increases in short duration rainfall intensity may be expected in the future but that they would not create severe impacts in the Mission/Wagg Creek system. The equivalent levels of imperviousness, however, suggest that the impacts on stream health could be far more damaging.  相似文献   
946.
ABSTRACT: Flash flooding is the rapid flooding of low lying areas caused by the stormwater of intense rainfall associated with thunderstorms. Flash flooding occurs in many urban areas with relatively flat terrain and can result in severe property damage as well as the loss of lives. In this paper, an integrated one‐dimensional (1‐D) and two‐dimensional (2‐D) hydraulic simulation model has been established to simulate stormwater flooding processes in urban areas. With rainfall input, the model simulates 2‐D overland flow and 1‐D flow in underground stormwater pipes and drainage channels. Drainage channels are treated as special flow paths and arranged along one or more sides of a 2‐D computational grid. By using irregular computation grids, the model simulates unsteady flooding and drying processes over urban areas with complex drainage systems. The model results can provide spatial flood risk information (e.g., water depth, inundation time and flow velocity during flooding). The model was applied to the City of Beaumont, Texas, and validated with the recorded rainfall and runoff data from Tropical Storm Allison with good agreement.  相似文献   
947.
20 0 0wasarelativelynormalyearintermsofglobaldisasterevents.Thegloballossfromnaturaldisasterswasapproximately 30billionUSD ,whereasthatinanyofthepreviousyearshadexceeded 1 0 0billionUSD .Theinsurancelossin 2 0 0 0wasonly 8.3billionUSD ,with 92 0 0 personskilled .Therewasn…  相似文献   
948.
微波技术在环境保护领域的应用   总被引:31,自引:0,他引:31  
综述了当前微波技术在环境保护领域的应用和研究状况,着重介绍了微波技术在废气处理,废水处理,固体废弃物处理,环境监测等方面的应用,讨论了应用存在的一些问题,并展望了微波技术在环境保护领域的应用前景。  相似文献   
949.
论述了小氮肥厂生产中废水、废气和废渣和产生及其废水,废气的治理方法与效果。介绍了利用废渣制砖和水泥的技术。  相似文献   
950.
次氯酸钠氧化脱除黄磷尾气中的硫、磷杂质   总被引:20,自引:3,他引:20  
熊辉  杨晓利  李光兴 《化工环保》2002,22(3):161-164
采用次氯酸钠氧化工艺净化黄磷尾气,在次氯酸钠溶液中有效氯的质量分数为0.65%,PH为9、反应温度为285K,气体流速为0.6-0.8L/min的条件下,对尾气中H2S、PH3的脱除率分别达到99.9%,和99.8%,出口含量分别小于0.2mg/m^3和7mg/m^3,对有机硫也有30%的脱除能力。  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