全文获取类型
收费全文 | 960篇 |
免费 | 32篇 |
国内免费 | 8篇 |
专业分类
安全科学 | 52篇 |
废物处理 | 43篇 |
环保管理 | 255篇 |
综合类 | 82篇 |
基础理论 | 258篇 |
环境理论 | 2篇 |
污染及防治 | 199篇 |
评价与监测 | 67篇 |
社会与环境 | 34篇 |
灾害及防治 | 8篇 |
出版年
2023年 | 8篇 |
2022年 | 16篇 |
2021年 | 12篇 |
2020年 | 6篇 |
2019年 | 14篇 |
2018年 | 20篇 |
2017年 | 21篇 |
2016年 | 28篇 |
2015年 | 30篇 |
2014年 | 26篇 |
2013年 | 60篇 |
2012年 | 58篇 |
2011年 | 58篇 |
2010年 | 40篇 |
2009年 | 60篇 |
2008年 | 68篇 |
2007年 | 60篇 |
2006年 | 56篇 |
2005年 | 32篇 |
2004年 | 42篇 |
2003年 | 39篇 |
2002年 | 35篇 |
2001年 | 9篇 |
2000年 | 15篇 |
1999年 | 14篇 |
1998年 | 14篇 |
1997年 | 11篇 |
1996年 | 14篇 |
1995年 | 15篇 |
1994年 | 18篇 |
1993年 | 11篇 |
1992年 | 9篇 |
1991年 | 7篇 |
1990年 | 5篇 |
1989年 | 9篇 |
1988年 | 5篇 |
1987年 | 2篇 |
1986年 | 3篇 |
1985年 | 8篇 |
1984年 | 4篇 |
1983年 | 8篇 |
1982年 | 8篇 |
1981年 | 3篇 |
1980年 | 4篇 |
1979年 | 3篇 |
1978年 | 2篇 |
1977年 | 4篇 |
1976年 | 2篇 |
1971年 | 1篇 |
1957年 | 2篇 |
排序方式: 共有1000条查询结果,搜索用时 97 毫秒
261.
In this article, we examine the effects of passive leadership on workplace incivility across two studies. Study 1 examines passive leadership–incivility relationships in a sample of employee–supervisor dyads, and Study 2 examines these relationships in a sample of employee–coworker dyads. Results from these studies suggest that passive leadership has a significant direct effect on behavioral incivility and an indirect effect through experienced incivility. Moreover, our results suggest that the relationship between experienced incivility and behavioral incivility is conditional on the level of passive leadership, such that the effect of experienced incivility on behavioral incivility is stronger at higher levels of passive leadership. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
262.
Watson A Glaspell B Christensen N Lachapelle P Sahanatien V Gertsch F 《Environmental management》2007,40(6):880-888
Many public land management agencies are committed to understanding and protecting recreation visitor experiences. Parks Canada
is deeply committed to that objective for visitors to Canada’s National Parks. This 2004 study, informed by a 2003 qualitative
study of visitor experiences and influences on those experiences at Auyuittuq National Park in Nunavut, worked to bring 50
potential elements of visitor experiences down to five articulated dimensions of the experience that is currently being received
at this remote eastern arctic park. A hypothesized set of 17 influences on experiences, also reduced to just two factors with
similar response patterns, and with some items that did not flow into the two factors, were used in a regression analysis
to understand the relationship between experiences and factors of influence. A sample of 61.8% (84) of the total recreation
visitor population 16 years of age or older was surveyed during deregistration after the trip. Knowledge about the dimensions
of the experiences currently received and factors of influence on those experiences can be used to guide selection of indicators
for describing objectives and prescribing monitoring protocol. 相似文献
263.
Accumulation of weathered polycyclic aromatic hydrocarbons (PAHs) by plant and earthworm species 总被引:12,自引:0,他引:12
Parrish ZD White JC Isleyen M Gent MP Iannucci-Berger W Eitzer BD Kelsey JW Mattina MI 《Chemosphere》2006,64(4):609-618
Experiments were conducted to assess the bioavailability of polyclycic aromatic hydrocarbons (PAHs) in soil from a Manufactured Gas Plant site. Three plant species were cultivated for four consecutive growing cycles (28 days each) in soil contaminated with 36.3 microg/g total PAH. During the first growth period, Cucurbita pepo ssp. pepo (zucchini) tissues contained significantly greater quantities of PAHs than did Cucumis sativus (cucumber) and Cucurbita pepo ssp. ovifera (squash). During the first growth cycle, zucchini plants accumulated up to 5.47 times more total PAH than did the other plants, including up to three orders of magnitude greater levels of the six ring PAHs. Over growth cycles 2-4, PAH accumulation by zucchini decreased by 85%, whereas the uptake of the contaminants by cucumber and squash remained relatively constant. Over all four growth cycles, the removal of PAHs by zucchini was still twice that of the other species. Two earthworm species accumulated significantly different amounts of PAH from the soil; Eisenia foetida and Lumbricus terrestris contained 0.204 and 0.084 microg/g total PAH, respectively, but neither species accumulated measurable quantities 5 or 6 ring PAHs. Lastly, in abiotic desorption experiments with an aqueous phase of synthetically prepared organic acid solutions, the release of 3 and 4 ring PAHs from soil was unaffected by the treatments but the desorption of 5-6 ring constituents was increased by up to two orders of magnitude. The data show that not only is the accumulation of weathered PAHs species-specific but also that the bioavailability of individual PAH constituents is highly variable. 相似文献
264.
Interest in facilitative predator plant interactions has focused upon above-ground systems. Underground physical conditions are distinctive, however, and we provide evidence that bush lupine, Lupinus arboreus, facilitates the survival of the predatory nematode Heterorhabditis marelatus. Because H. marelatus is prone to desiccation and lupines maintain a zone of moist soil around their taproots even during dry periods, we hypothesized that dry-season nematode survival under lupines might be higher than in the surrounding grasslands. We performed field surveys and measured nematode survival in lupine and grassland rhizospheres under wet- and dry-season conditions. Nematodes survived the crucial summer period better under lupines than in grasslands; however, this advantage disappeared in wet, winter soils. Modeling the probability of nematode population extinction showed that, while even large nematode cohorts were likely to go extinct in grasslands, even small cohorts in lupine rhizospheres were likely to survive until the arrival of the next prey generation. Because this nematode predator has a strong top-down effect on lupine survival via its effect on root-boring larvae of the ghost moth Hepialus californicus, this facilitative interaction may enable a belowground trophic cascade. Similar cases of predator facilitation in seasonally stressful environments are probably common in nature. 相似文献
265.
Hoff SJ Bundy DS Nelson MA Zelle BC Jacobson LD Heber AJ Ni J Zhang Y Koziel JA Beasley DB 《Journal of the Air & Waste Management Association (1995)》2006,56(5):581-590
It is a common practice in the midwestern United States to raise swine in buildings with under-floor slurry storage systems designed to store manure for up to one year. These so-called "deep-pit" systems are a concentrated source for the emissions of ammonia (NH3), hydrogen sulfide (H2S), and odors. As part of a larger six-state research effort (U.S. Department of Agriculture-Initiative for Future Agriculture and Food Systems Project, "Aerial Pollutant Emissions from Confined Animal Buildings"), realtime NH3 and H2S with incremental odor emission data were collected for two annual slurry removal events. For this study, two 1000-head deep-pit swine finishing facilities in central Iowa were monitored with one-year storage of slurry maintained in a 2.4 m-deep concrete pit (or holding tank) below the animal-occupied zone. Results show that the H2S emission, measured during four independent slurry removal events over two years, increased by an average of 61.9 times relative to the before-removal H2S emission levels. This increase persisted during the agitation process of the slurry that on average occurred over an 8-hr time period. At the conclusion of slurry agitation, the H2S emission decreased by an average of 10.4 times the before-removal emission level. NH3 emission during agitation increased by an average of 4.6 times the before-removal emission level and increased by an average of 1.5 times the before-removal emission level after slurry removal was completed. Odor emission increased by a factor of 3.4 times the before-removal odor emission level and decreased after the slurry-removal event by a factor of 5.6 times the before-removal emission level. The results indicate that maintaining an adequate barn ventilation rate regardless of animal comfort demand is essential to keeping gas levels inside the barn below hazardous levels. 相似文献
266.
267.
268.
Cécile Courdier John Boudjarane Valérie Malan Christine Muti Brian Sperelakis-Beedham Sylvie Odent Sylvie Jaillard Chloé Quelin Cédric Le Caignec Olivier Patat Charlotte Dubucs Sophie Julia Caroline Schluth-Bolard Carole Goumy Sylvia Redon Jean-Baptiste Gaillard Minh Tuan Huynh Céline Dupont Anne-Claude Tabet Guillaume Cogan François Vialard Rodolphe Dard Guillaume Jedraszak Florence Jobic Mathilde Lefebvre Geneviève Quenum Saori Inai Mélanie Rama Fanny Sauvestre Frédéric Coatleven Julie Thomas Caroline Rooryck 《黑龙江环境通报》2023,43(6):734-745
269.
270.