全文获取类型
收费全文 | 37401篇 |
免费 | 383篇 |
国内免费 | 334篇 |
专业分类
安全科学 | 1087篇 |
废物处理 | 1369篇 |
环保管理 | 5337篇 |
综合类 | 6900篇 |
基础理论 | 9672篇 |
环境理论 | 17篇 |
污染及防治 | 9756篇 |
评价与监测 | 2150篇 |
社会与环境 | 1574篇 |
灾害及防治 | 256篇 |
出版年
2022年 | 252篇 |
2021年 | 283篇 |
2019年 | 277篇 |
2018年 | 465篇 |
2017年 | 448篇 |
2016年 | 724篇 |
2015年 | 607篇 |
2014年 | 863篇 |
2013年 | 2978篇 |
2012年 | 1104篇 |
2011年 | 1494篇 |
2010年 | 1156篇 |
2009年 | 1392篇 |
2008年 | 1551篇 |
2007年 | 1603篇 |
2006年 | 1411篇 |
2005年 | 1183篇 |
2004年 | 1143篇 |
2003年 | 1143篇 |
2002年 | 1117篇 |
2001年 | 1428篇 |
2000年 | 1029篇 |
1999年 | 640篇 |
1998年 | 456篇 |
1997年 | 455篇 |
1996年 | 516篇 |
1995年 | 558篇 |
1994年 | 536篇 |
1993年 | 485篇 |
1992年 | 444篇 |
1991年 | 472篇 |
1990年 | 491篇 |
1989年 | 457篇 |
1988年 | 411篇 |
1987年 | 390篇 |
1986年 | 368篇 |
1985年 | 366篇 |
1984年 | 378篇 |
1983年 | 390篇 |
1982年 | 384篇 |
1981年 | 379篇 |
1980年 | 327篇 |
1979年 | 360篇 |
1978年 | 279篇 |
1977年 | 259篇 |
1976年 | 245篇 |
1975年 | 234篇 |
1974年 | 238篇 |
1973年 | 250篇 |
1972年 | 246篇 |
排序方式: 共有10000条查询结果,搜索用时 15 毫秒
881.
882.
883.
Marvin W. Jackson 《Journal of the Air & Waste Management Association (1995)》2013,63(12):697-702
An investigation has been made of the suitability of a nondispersive infrared analyzer and two flame-ionization analyzers for measuring the total hydrocarbon concentrations of automobile exhaust gas. The investigation consisted of measuring relative responses of various hydrocarbons, checking for possible exhaust gas interferences and finally comparing exhaust hydrocarbon concentrations indicated by the flame-ionization analyzer to those indicated by the infrared analyzer. The infrared analyzer has high relative responses for parraffins and low responses for olefins, acetylenes, and aromatics. Also, the infrared indicated hydrocarbon concentrations must be corrected for exhaust water vapor interference. When the flameionization analyzers are operated at conditions that result in approximately uniform response to hydrocarbons and low oxygen interference, the exhaust hydrocarbon concentrations indicated by either flameionization analyzer are better approximations of the total hydrocarbon concentration than those indicated by the infrared analyzer. 相似文献
884.
Performance and Cost Comparisons between Fabric Filters and Alternate Participate Control Techniques
J.D. McKenna J. C. Mycock W.O. Lipscomb 《Journal of the Air & Waste Management Association (1995)》2013,63(12):1144-1148
A study was conducted to evaluate performance and cost comparisons of fabric filters and alternate fine particulate control techniques. In relating the removal of fine particulate to costs, due to the lack of fractional efficiency data, it was found necessary to treat a specific application in order to make the study manageable. The case chosen is that of the coal fired industrial boiler since Enviro-Systems has a pilot program in this application area. 相似文献
885.
Robert W. Fri 《Journal of the Air & Waste Management Association (1995)》2013,63(9):912-914
As many of you know, I previously served as Deputy Administrator of the Environmental Protection Agency at a time when the problem of air pollution control was reaching a peak of public awareness. The work of the Air Pollution Control Association in investigating facts and accelerating the development of solutions earned my high respect then and my continued admiration now. 相似文献
886.
Michael J. Massey Robert W. Dunlap 《Journal of the Air & Waste Management Association (1995)》2013,63(10):1019-1027
Two processes are currently being employed in North America for the desulfurization of coke oven gas, the Vacuum Carbonate System, and the Stretford System. A third, the Sulfi-ban Process, which was recently announced, now has several plants scheduled for construction. Overall operating requirements for each of these processes are considered in detail. Emphasis is placed on an identification of power and steam requirements, the types and amounts of solid and/or liquid waste streams produced together with methods for their treatment, and the net desulfurization efficiencies achieved by each process. Detailed estimates of capital and operating costs for desulfurization are considered, and equipment needs for environmental control requirements are discussed. 相似文献
887.
G. Van Houte B. Delmon J.C. Maon Ph. Dumont 《Journal of the Air & Waste Management Association (1995)》2013,63(10):1030-1033
This publication concerns the dry removal of SO2 from gases using limestone absorbents. It reports bench-scale experiments made with commercial samples of powdered limestone (CaCO3) activated by addition of a cheap substance, namely CaCl2. The absorption was carried out in a fluidized bed traversed by the flue gases, between 600° and 900° C. The degree and rate of transformation of CaCO3 to CaSO4 in the presence of SO2 and air have been compared for unmodified and modified absorbents. Initial rates of reaction, and the variation of the rate of absorption with time have been measured. The influence of the SO2 content of the gas has been assessed. At 700° C, the maximum degree of transformation of activated limestone to sulfate exceeds 90%, whereas untreated CaCO3 transforms only to 16–20%. At the same temperature, more than 90% of SO2 contained In a gas carrying 0.35% SO2 is removed. Because of the much smaller quantity of solid absorbent required, dry absorption processes based on the modified absorbents might get renewed interest. The modified absorbents might also be used for in situ absorption in fluidized bed combustion, in which the temperatures are in the range studied in the present paper. 相似文献
888.
889.
The importance of the incorporation of personal communication devices in emergency evacuation simulators will be discussed. Four case studies are examined to identify usage statistics and human behavior when using the devices in an emergency. The case studies are: 9/11 World Trade Center Attacks, London train bombings, Virginia Tech shooting and United Flight #93. The case studies’ findings are implemented into the Vacate evacuation simulator, which uses particle swarm optimization to mimic human pedestrian behavior. The physical actions of using a device, as well as the reaction to the information transmitted during usage, are examined. Findings show that the effects of the personal communication devices can affect individuals that are close to the user of the device, as well as those not in the local vicinity of the user. These effects, combined with the rapid mainstream acceptance of communication technologies, justify the implementation of personal communication devices into evacuation simulators. 相似文献
890.