全文获取类型
收费全文 | 3516篇 |
免费 | 82篇 |
国内免费 | 42篇 |
专业分类
安全科学 | 178篇 |
废物处理 | 138篇 |
环保管理 | 953篇 |
综合类 | 308篇 |
基础理论 | 845篇 |
环境理论 | 2篇 |
污染及防治 | 847篇 |
评价与监测 | 208篇 |
社会与环境 | 132篇 |
灾害及防治 | 29篇 |
出版年
2023年 | 18篇 |
2022年 | 30篇 |
2021年 | 39篇 |
2020年 | 36篇 |
2019年 | 45篇 |
2018年 | 72篇 |
2017年 | 68篇 |
2016年 | 115篇 |
2015年 | 75篇 |
2014年 | 88篇 |
2013年 | 386篇 |
2012年 | 130篇 |
2011年 | 192篇 |
2010年 | 156篇 |
2009年 | 159篇 |
2008年 | 176篇 |
2007年 | 182篇 |
2006年 | 162篇 |
2005年 | 98篇 |
2004年 | 130篇 |
2003年 | 128篇 |
2002年 | 110篇 |
2001年 | 66篇 |
2000年 | 57篇 |
1999年 | 56篇 |
1998年 | 44篇 |
1997年 | 50篇 |
1996年 | 55篇 |
1995年 | 60篇 |
1994年 | 47篇 |
1993年 | 47篇 |
1992年 | 34篇 |
1991年 | 37篇 |
1990年 | 39篇 |
1989年 | 32篇 |
1988年 | 34篇 |
1987年 | 31篇 |
1986年 | 42篇 |
1985年 | 28篇 |
1984年 | 42篇 |
1983年 | 33篇 |
1982年 | 38篇 |
1981年 | 34篇 |
1980年 | 22篇 |
1979年 | 20篇 |
1978年 | 16篇 |
1977年 | 15篇 |
1976年 | 15篇 |
1974年 | 11篇 |
1972年 | 10篇 |
排序方式: 共有3640条查询结果,搜索用时 0 毫秒
221.
James C. F. Wang Harvey Patashnick George Rupprecht 《Journal of the Air & Waste Management Association (1995)》2013,63(9):1018-1021
A new real-time dust mass monitor has been developed by combining an automatic isokinetic sampling probe with a tapered element oscillating microbalance (TEOM). Fly ash from a room temperature wind tunnel is sampled through the isokinetic sampler and collected on an astroquartz mat filter in the TEOM detector. The filter is first excited and oscillated at low frequency (about 200 Hz). As the particles deposit on the filter, the mass increase of the filter is reflected in a frequency reduction which yields the collected particle mass directly in real time. The TEOM detector normally has a high mass resolution (10?9 g) and wide dynamic range (1055–1066). It is desensitized for high particle loading applications. Good agreement has been obtained between the mass collected through the isokinetic sampling system and the weight loss of the dust feeder, in real time. The body of information presented in this paper is directed to those concerned with particle emission and control in fossil fuel combustion systems. 相似文献
222.
223.
James L. Lindgren Henry J. Krauss Marye Anne Fox 《Journal of the Air & Waste Management Association (1995)》2013,63(2):166-168
A demonstration of the GHEMFIX solidification/stabilization process was conducted under the United States Environmental Protection Agency’s (EPA) Superfund Innovative Technology Evaluation (SITE) program. The demonstration was conducted in March 1989, at the Portable Equipment Salvage Company (PESC) uncontrolled hazardous waste site in Clackamas, Oregon. Waste containing lead, copper, and polychlorinated biphenyls (PCBs) from four different areas of the site were treated. Results showed substantial reduction of leachable lead and copper between the untreated waste and treated waste utilizing the EPA Toxicity Characteristics Leaching Procedure (TCLP) test. The effectiveness of this process for immobilizing PCBs could not be determined since the raw waste did not leach PCBs at high concentrations, utilizing the TCLP test. Data from other leaching tests for lead and copper would need to be utilized as input into a site specific groundwater model to determine whether solidification/stabilization would be an acceptable remedy for the site. Physical testing results indicated durability in exposed conditions. 相似文献
224.
James McCarroll 《Journal of the Air & Waste Management Association (1995)》2013,63(6):652-656
The increased use of coal projected under the National Energy Plan has raised fears of increased morbidity and mortality related to fossil fuel combustion products. The evidence for adverse health effects from the major emissions of coal combustion is considered, as well as the basis for predictions of an increase in morbidity and mortality. It can be concluded that with presently available control technology, no detectable adverse health effects will be observed associated with increased coal combustion. It is further concluded that a reduction in energy supply, or a large increase in energy cost leading to reduced energy supply to lower socio-economic groups will cause far more demonstrable adverse health effects than increased coal utilization. 相似文献
225.
James L. Littlejohn David B. Shaver William C. Malm 《Journal of the Air & Waste Management Association (1995)》2013,63(8):879-880
This study includes an application of the first two phases of a new three-phased decision-making structure that was developed to overcome the problems related to ecological safety and social justice in site selection applications. It was conducted on a current site selection problem related to the municipal solid waste disposal facilities in Kocaeli, the most industrialized region of Turkey. In order to assess the deficiencies of the legal site selection procedures related to ecological safety, two different decision tree modes were applied separately. The first mode (“Legislation”) concerns the current buffer zone applications given in the regulations, while the second one (“Proposed”) includes the applications of the new decision-making structure proposed in this study. Since it was assumed that the subjective tendencies of the decision makers on the weightings would have a significant effect on the final decision, these two modes were assessed by employing two different weighting models. The results were obtained from all of the scenarios related to selection of suitable sites with three different area requirements (15, 250, and 500 acres) for the solid wastes generated in the Kocaeli region. The results showed that the possible changes in the decision structure could cause significant differences in the final decision related to selection of the most suitable sites. The most highest and lowest differences were at the “Legislation” mode for 15 acres and 500 acres, respectively. Furthermore, the results obtained in the study showed that the possible differentiations in the criteria weightings could also cause significant differences in the suitability ranking. Therefore, to get a reliable final decision, a statistical assessment of these differentiations should be made.
Implications: The results showed that the possible changes in the decision structure could cause significant differences in the final decision related to selection of the most suitable sites. Furthermore, the results obtained in the study showed that the possible differentiations in the criteria weightings could also cause significant differences in the suitability ranking. Therefore, to get a reliable final decision, a statistical assessment of these differentiations should be made. 相似文献
226.
Douglas W. Cooper 《Journal of the Air & Waste Management Association (1995)》2013,63(2):205-208
Factors which help minimize pressure drop at a given level of collection efficiency for a bed packed with roughly spherical collectors are studied here by using the quality factor, the ratio of the single collector collection efficiency to the force per unit area on the single collector. This analysis indicates that energy-efficient designs can be obtained as follows: choose a representative particle size; if impaction predominates, design for an impaction parameter near one; if interception predominates, design for the smallest packing diameters feasible; if gravitational settling predominates, design for the largest packing diameters possible; if diffusion predominates, design for collector Reynolds numbers near 102. Some more general cases are also discussed. 相似文献
227.
James E. Hardy John J. Knarr 《Journal of the Air & Waste Management Association (1995)》2013,63(4):376-379
This paper reports the development of a rapid, continuous technique for analyzing fixed nitrogen species (NH3, HCN, CH3NH2, etc.). The technique uses a platinum catalyst at low pressure in combination with a conventional chemiluminescent NO x analyzer. Previous workers observed that conventional stainless steel catalysts, and platinum catalysts operated at atmospheric pressure, do not reliably convert NH3 to NO. The most serious problem was the variation in the efficiency of these catalysts with operating conditions. Changes in temperature, gas composition, or XNH3 could change the conversion efficiency from 99.9% to <30%. The new conversion technique, however, is quantitative up to several thousand ppm NH3 in either O2/He or O2/CO2/N2. 相似文献
228.
229.
230.
Douglas W. Grosse 《Journal of the Air & Waste Management Association (1995)》2013,63(5):603-614
The U.S. Congress and the U.S. Environmental Protection Agency believe that treatment and recovery techniques should be given maximum priority when considering methods for managing the nation's generated hazardous waste. A prohibition for the disposal of certain categories of hazardous wastes either directly onto or into the land without being treated to an accepted degree prior to such disposal practice has been promulgated.1 Wastes containing toxic metals and cyanide complexes have been selected as a group to be restricted. Due to the high generation rate associated with this category, a large capacity of waste treatment processing will be required. Existing and emerging treatment alternatives which are or have the potential to be employed for waste treatment of metal bearing wastes are presented in this paper. 相似文献