全文获取类型
收费全文 | 900篇 |
免费 | 12篇 |
国内免费 | 11篇 |
专业分类
安全科学 | 39篇 |
废物处理 | 32篇 |
环保管理 | 205篇 |
综合类 | 121篇 |
基础理论 | 224篇 |
污染及防治 | 204篇 |
评价与监测 | 67篇 |
社会与环境 | 24篇 |
灾害及防治 | 7篇 |
出版年
2023年 | 6篇 |
2022年 | 9篇 |
2021年 | 8篇 |
2020年 | 17篇 |
2019年 | 13篇 |
2018年 | 14篇 |
2017年 | 12篇 |
2016年 | 18篇 |
2015年 | 18篇 |
2014年 | 30篇 |
2013年 | 84篇 |
2012年 | 34篇 |
2011年 | 56篇 |
2010年 | 29篇 |
2009年 | 42篇 |
2008年 | 43篇 |
2007年 | 67篇 |
2006年 | 35篇 |
2005年 | 32篇 |
2004年 | 28篇 |
2003年 | 30篇 |
2002年 | 32篇 |
2001年 | 26篇 |
2000年 | 15篇 |
1999年 | 13篇 |
1998年 | 11篇 |
1997年 | 13篇 |
1996年 | 12篇 |
1995年 | 7篇 |
1994年 | 14篇 |
1993年 | 13篇 |
1992年 | 7篇 |
1991年 | 6篇 |
1990年 | 10篇 |
1989年 | 12篇 |
1988年 | 6篇 |
1987年 | 9篇 |
1986年 | 5篇 |
1985年 | 6篇 |
1984年 | 8篇 |
1983年 | 4篇 |
1982年 | 4篇 |
1981年 | 12篇 |
1980年 | 5篇 |
1979年 | 6篇 |
1978年 | 4篇 |
1977年 | 4篇 |
1975年 | 8篇 |
1974年 | 5篇 |
1972年 | 3篇 |
排序方式: 共有923条查询结果,搜索用时 656 毫秒
371.
Branden B. Johnson 《Environmental management》1987,11(5):571-586
Nuclear and chemical waste facilities can be successfully sited, despitenimby responses, if siting programs account for the sources of public concern. Irrational fear is not the main source; instead, waste managers must deal with perceived inequities in the distribution of benefits and costs, and concern about facility safety. Benefit-cost inequities may be dealt with in part by keeping wastes where they are generated, through political restrictions, or by providing economic compensation and political incentives (for example, a local veto). Assuring people of facility safety includes allowing local control (monitoring, health assessment, regulation), and enhancing trust of facility managers through such means as rectifying past mistakes, individual-oriented education campaigns, and negotiation of compensation packages with local residents. These means should reduce —without eliminating—public opposition to local siting of nuclear and chemical waste facilities. 相似文献
372.
Robert E. Johnson 《补救:环境净化治理成本、技术与工艺杂志》1991,1(2):123-146
The continuous and discontinuous release of petroleum hydrocarbons from an oil refinery in Alaska resulted in the contamination of an unconfined glacial outwash aquifer. Geologic conditions at the site allowed for the vertical migration of hydrocarbon product to the water table and subsequent formation of an areally extensive floating product layer. Since the petroleum hydrocarbon phase would provide a major source of BTX (benzene, toluene, xylene) contamination to the groundwater, interim product and groundwater recovery measures were initiated to limit aquifer degradation. Phase I remedial activities involved the operation of nine well pairs, with one well used for groundwater extraction and the other for product recovery. Phases II and III involved expansion of the recovery well network and use of a two-pump system. Petroleum product recovered was reprocessed at the refinery. Contaminated groundwater was initially treated using the refinery's wastewater treatment system, but treatment inefficiencies and continued system expansion necessitated use of a separate treatment unit. Performance evaluations indicate that the remedial phases have been successful in halting further contaminant migration and in recovering a significant volume of the released petroleum hydrocarbons. 相似文献
373.
Scanning electron micrographs (SEM) demonstrate the growth of an epiphytic diatom and bacterial community on the surface of dialysis membranes incubated In situ, Narragansett Bay, Rhode Island (USA). A comparison is made between brushed and unbrushed tubes in summer, and unbrushed tubes in winter. Detrital deposition and epiphytic growth may decrease surface area and, by uptake and regeneration, influence nutrient flux through the membrane. 相似文献
374.
375.
376.
Annette L. Cowie Pete Smith Dale Johnson 《Mitigation and Adaptation Strategies for Global Change》2006,11(5-6):979-1002
Interest in bioenergy is growing across the Western world in response to mounting concerns about climate change. There is a risk of depletion of soil carbon stocks in biomass production systems, because a higher proportion of the organic matter and nutrients are removed from the site, compared with conventional agricultural and forestry systems. This paper reviews the factors that influence soil carbon dynamics in bioenergy systems, and utilises the model FullCAM to investigate the likely magnitude of soil carbon change where bioenergy systems replace conventional land uses. Environmental and management factors govern the magnitude and direction of change. Soil C losses are most likely where soil C is initially high, such as where improved pasture is converted to biomass production. Bioenergy systems are likely to enhance soil C where these replace conventional cropping, as intensively cropped soils are generally depleted in soil C. Measures that enhance soil C include maintenance of productivity through application of fertilisers, inclusion of legumes, and retention of nutrient-rich foliage on-site. Modelling results demonstrate that loss of soil carbon in bioenergy systems is associated with declines in the resistant plant matter and humified soil C pools. However, published experimental data and modelling results indicate that total soil C loss in bioenergy systems is generally small. Thus, although there may be some decline in soil carbon associated with biomass production, this is negligible in comparison with the contribution of bioenergy systems towards greenhouse mitigation through avoided fossil fuel emissions. 相似文献
377.
David R. Johnson MD Rachel A. Fisher Jenny J. Helwick Dennis L. Murray Maria J. Patterson Frances P. Downes 《黑龙江环境通报》1994,14(6):455-458
The association between gestational infection with human parvovirus (B19) and fetal loss has increased interest in this virus and demand for diagnostic testing. However, serological assays for B19 are not yet widely available. Maternal serum alpha-fetoprotein (MSAFP) testing is commonly used during the second trimester to screen for various fetal defects. We attempted to determine whether an elevated level of MSAFP would be an appropriate indication for B19-specific tests. Over a 26-month period, MSAFP tests were performed at Michigan State University for 21 392 women. Sera remaining after that testing were stored frozen. Of these, 22 case samples—from women with MSAFP levels greater than 3·0 multiples of the median (MOM) and pregnancies that ended in fetal loss—and 44 matched control samples—from women with MSAFP levels greater than 0·4 and less than 2·2 MOM and live births at term—were tested for B19 antibodies. None of the 66 samples was IgM positive, while 33 (50 per cent) were IgG positive. The presence of IgG was not significantly associated with case or control status (matched odds ratio=0·77, 95 per cent confidence interval 0·28–2·11). These findings are consistent with other studies indicating prior infection in approximately half of adults and suggest that elevated screening MSAFP levels, in the absence of other evidence of B19 infection, should not prompt B19-specific testing. 相似文献
378.
379.
Sacral agenesis was diagnosed sonographically in the fetus of a diabetic mother and pancreatic agenesis was found additionally at autopsy. 相似文献
380.
R. Frank K. Johnson H. E. Braun C. G. Halliday J. Harvey 《Environmental monitoring and assessment》1991,16(2):137-150
Permethrin drift from two aerial applications at each of two sites in a potato growing area in Ontario were measured to a maximum distance of 61 m outside the treatment area. Droplet drift did not enter the adjacent surface water streams at either study site, since there was little or no wind on the four occasions. The concentration of the insecticide in soil as a result of drifting off site was significantly lower than the amount deposited on the treatment area. The spray drifting off-target was generally made up of droplets <100 m. Permethrin residues were detected in the water and sediment samples collected after treatment along the Bailey Creek and Beeton Creek; however, these levels did not cause lethal or sublethal effects to aquatic invertebrates and fish species. Based on the conditions and results of this study, it is concluded that a buffer zone of 65 m around sensitive and productive bodies of water would be effective and practical. 相似文献