全文获取类型
收费全文 | 828篇 |
免费 | 17篇 |
国内免费 | 7篇 |
专业分类
安全科学 | 31篇 |
废物处理 | 30篇 |
环保管理 | 191篇 |
综合类 | 112篇 |
基础理论 | 185篇 |
污染及防治 | 187篇 |
评价与监测 | 54篇 |
社会与环境 | 53篇 |
灾害及防治 | 9篇 |
出版年
2022年 | 8篇 |
2021年 | 15篇 |
2020年 | 11篇 |
2019年 | 12篇 |
2018年 | 22篇 |
2017年 | 25篇 |
2016年 | 19篇 |
2015年 | 28篇 |
2014年 | 20篇 |
2013年 | 93篇 |
2012年 | 33篇 |
2011年 | 45篇 |
2010年 | 28篇 |
2009年 | 29篇 |
2008年 | 47篇 |
2007年 | 52篇 |
2006年 | 40篇 |
2005年 | 20篇 |
2004年 | 20篇 |
2003年 | 41篇 |
2002年 | 26篇 |
2001年 | 12篇 |
2000年 | 14篇 |
1999年 | 5篇 |
1998年 | 11篇 |
1997年 | 9篇 |
1996年 | 10篇 |
1995年 | 9篇 |
1994年 | 19篇 |
1993年 | 13篇 |
1992年 | 5篇 |
1991年 | 8篇 |
1990年 | 10篇 |
1989年 | 4篇 |
1988年 | 5篇 |
1986年 | 6篇 |
1985年 | 9篇 |
1984年 | 6篇 |
1983年 | 12篇 |
1982年 | 11篇 |
1981年 | 7篇 |
1980年 | 7篇 |
1979年 | 6篇 |
1978年 | 6篇 |
1977年 | 4篇 |
1974年 | 3篇 |
1973年 | 1篇 |
1972年 | 1篇 |
1971年 | 3篇 |
1970年 | 1篇 |
排序方式: 共有852条查询结果,搜索用时 62 毫秒
461.
Environmental implications of urbanization and lifestyle change in China: Ecological and Water Footprints 总被引:2,自引:0,他引:2
Klaus Hubacek Dabo Guan John Barrett Thomas Wiedmann 《Journal of Cleaner Production》2009,17(14):1241-1248
Since the open door policy in 1978 China has undergone enormous economic and social changes making China to be one of the largest economies and consumers of resources in the world. The pronounced differences in income and lifestyles especially between urban and rural China were also part of China's economic rebirth.This paper explores current trajectories and scenarios for urbanization and lifestyle changes and other important socio-economic trends in China. The implications of these changes are analysed for Beijing in particular and then compared to China for the year 2020. These changes by 2020 are modelled using input–output analysis in combination with the Ecological Footprint and Water Footprint. 相似文献
462.
Reducing non-contact electric arc injuries: an investigation of behavioral and organizational issues
PROBLEM: It is estimated that 5 to 10 arc flash explosions occur in electric equipment every day in the United States. In the mining industry the largest single injury category of electrical injuries are caused by non-contact electrical arcs. METHOD: This investigation progressed in two phases: (a) 836 Mine Safety and Health Administration (MSHA) reports of electric arcing incidents that occurred over a period of 11 years were reviewed, and (b) personal interviews were conducted with 32 individuals. A theoretical Safe Job Performance Model guided the study. RESULTS: Behavioral dimensions were identified and included the effect of worker experience, judgment and decision-making ability, behavioral and organizational controls, and safety culture. SUMMARY: The National Institute for Occupational Safety and Health (NIOSH) conducted an investigation of behavioral components associated with arc flash incidents and developed recommendations for interventions based on findings. IMPACT ON INDUSTRY: This study fills a vacuum in electrical training with a focus on the organizational and behavioral aspects of arc flash incidents. The research is cross-cutting in its scope, in that the results apply not only to mining and construction, but many other industries employing electricians. Although the majority of mine electrical injuries are the results of burns from electrical arcs, few miners are aware that such a hazard exists. A safety training program, which includes a video and an instructor's discussion guide, was developed for electricians based on this study's findings. "Arc Flash Awareness" was released in 2007 (DHHS NIOSH Publication No.2007-116D) and is available through 1-800 CDC INFO. Phone: 1-800 232-4636 or email cdcinfo@cdc.gov. It is also available from MSHA at MSHADistribution@dol.gov or 304-256-3257 (DVD-576). Private industry is producing Portuguese and Spanish language translations. 相似文献
463.
464.
This study examined the relationship between age and job performance evaluations for newcomers recently hired into entry-level positions in public accounting firms. We predicted and found a negative relationship between age and job performance evaluations. This relationship was eliminated after controlling for undergraduate grade average and prior work experience, operationalized as the number of jobs that a newcomer had previously held. Results are discussed in terms of the possibility of negative age effects in entry-level positions and the potential reasons for such findings. © 1998 John Wiley & Sons, Ltd. 相似文献
465.
466.
Klara Hilscherova Miroslav Machala Kurunthachalam Kannan Alan L. Blankenship John P. Giesy 《Environmental science and pollution research international》2000,7(3):159-171
In vitro cell bioassays are useful techniques for the determination of receptor-mediated activities in environmental samples containing complex mixtures of contaminants. The cell bioassays determine contamination by pollutants that act through specific modes of action. This article presents strategies for the evaluation of aryl hydrocarbon receptor (AhR)-(hereafter referred as dioxin-like) or estrogen receptor (ER)-mediated activities of potential endocrine disrupting compounds (EDCs) in complex environmental mixtures. Extracts from various types of environmental or food matrices can be tested by this technique to evaluate their 2,3,7,8-tetrachlorodibenzop-dioxin equivalents (TCDD-EQs) or estrogenic equivalents (E2-EQs) and to identify contaminated samples that need further investigation using resource-intensive instrumental analyses. Fractionation of sample extracts exhibiting significant activities, and subsequent reanalysis with the bioassays can identify important classes of contaminants that are responsible for the observed activity. Effect-directed chemical analysis is performed only for the active fractions to determine the responsible compounds. Mass-balance estimates of all major compounds contributing to the observed effects can be calculated to determine if all of the activity has been identified, and to assess the potential for interactions such as synergism or antagonism among contaminants present in the complex mixtures. The bioassay approach is an efficient (fast and cost effective) screening system to identify the samples of interest and to provide basic information for further analysis and risk evaluation. 相似文献
467.
Deborah A. Hutchinson Alan H. Savitzky Akira Mori Jerrold Meinwald Frank C. Schroeder 《Chemoecology》2008,18(3):181-190
Summary.
Rhabdophis tigrinus obtains defensive steroids (bufadienolides) from its diet and sequesters those compounds in specialized structures on its
neck known as nuchal glands. Hatchling snakes lacking these steroids must acquire them from toads consumed as prey. Here we
show that females provision bufadienolides to their offspring in amounts correlated to the quantity in their own nuchal glands;
thus, chemically protected mothers produce defended offspring. Bufadienolides can be provisioned to embryos via deposition
in yolk and by transfer across the egg membranes within the oviducts. Maternally provisioned bufadienolides persist in the
nuchal glands of juvenile snakes from the time of hatching in late summer until the following spring, when toads of ingestible
size become abundant. Therefore, maternal provisioning may provide chemical protection from predators for young R. tigrinus in the absence of dietary sources of bufadienolides. 相似文献
468.
The functional response of Daphnia, a common pelagic herbivore in lakes, was assessed with a combination of secondary and meta-analyses of published data and new data from an experiment conducted using very low food levels. Secondary analyses of literature data (28 studies, n = 239-393) revealed a significant positive influence of food concentration on Daphnia clearance rate at low food levels, i.e., evidence of an overall Type III functional response. This result was not an artifact of including data from Daphnia that were exhausted from prolonged food deprivation (more than three hours at very low food). Meta-analysis of Daphnia clearance rate vs. food concentration across a range of low food concentrations (eight studies) showed a significantly positive slope across studies, which also supports the presence of a Type III response. Congruent with these analyses of published data, the feeding experiment showed clear evidence of a Type III functional response for D. pulicaria feeding on Ankistrodesmus falcatus. Food levels at which Daphnia clearance rate declined with decreasing food were near the minimum resource requirement for Daphnia population maintenance at steady state (R*). We suggest that Type III responses are more common than previously believed, perhaps because of the relative paucity of observations at low food levels, and that reduced prey mortality at low phytoplankton densities could be a stabilizing mechanism for Daphnia-phytoplankton systems under resource scarcity. 相似文献
469.
Comparative phylogeography of marine cladocerans 总被引:1,自引:0,他引:1
We examined the population genetics of six species of marine cladocerans, using a ~600 bp fragment of the cytochrome oxidase
subunit I gene sequence. Phylogenetic analysis revealed significant intraspecific, semi-allopatric phylogenetic breaks in
four out of five species belonging to the Podonidae, supporting an ancient radiation and oceanic expansion for this group.
By contrast, Penilia
avirostris (Sididae) displayed no phylogeographic structure across a global sampling, suggesting a recent worldwide expansion. Our results
also show a transoceanic distribution of identical or very similar haplotypes in several species of marine Cladocera, which
may be interpreted as either natural transport or evidence of recent anthropogenic transport. If the latter is the case, marine
cladocerans represent one of the first genetically documented cases of exotic or invasive marine zooplankton, likely an underreported
group.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.
Sequence data from this article have been deposited with the EMBL/GenBank Data Libraries under accession nos. EU675871–EU675924. 相似文献
470.
Continental‐Scale River Flow Modeling of the Mississippi River Basin Using High‐Resolution NHDPlus Dataset 下载免费PDF全文
Ahmad A. Tavakoly Alan D. Snow Cédric H. David Michael L. Follum David R. Maidment Zong‐Liang Yang 《Journal of the American Water Resources Association》2017,53(2):258-279
As a key component of the National Flood Interoperability Experiment (NFIE), this article presents the continental scale river flow modeling of the Mississippi River Basin (MRB), using high‐resolution river data from NHDPlus. The Routing Application for Parallel computatIon of Discharge (RAPID) was applied to the MRB with more than 1.2 million river reaches for a 10‐year study (2005‐2014). Runoff data from the Variable Infiltration Capacity (VIC) model was used as input to RAPID. This article investigates the effect of topography on RAPID performance, the differences between the VIC‐RAPID streamflow simulations in the HUC‐2 regions of the MRB, and the impact of major dams on the streamflow simulations. The model performance improved when initial parameter values, especially the Muskingum K parameter, were estimated by taking topography into account. The statistical summary indicates the RAPID model performs better in the Ohio and Tennessee Regions and the Upper and Lower Mississippi River Regions in comparison to the western part of the MRB, due to the better performance of the VIC model. The model accuracy also increases when lakes and reservoirs are considered in the modeling framework. In general, results show the VIC‐RAPID streamflow simulation is satisfactory at the continental scale of the MRB. 相似文献