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41.
Sexual signalling and viability in a wolf spider (Hygrolycosa rubrofasciata): measurements under laboratory and field conditions 总被引:4,自引:0,他引:4
Janne S. Kotiaho Rauno V. Alatalo Johanna Mappes Silja Parri 《Behavioral ecology and sociobiology》1999,46(2):123-128
This study examined the crucial prediction of the conditional-handicap theory, the relationship between male sexual trait
size and male viability, in the wolf spider Hygrolycosa rubrofasciata. In this species, males court females by drumming dry leaves with their abdomen, and males with the highest drumming rate
enjoy highest mating success. We determined male drumming rate, body mass, and mobility, which reflects mate-searching activity,
in relation to male survival. Because it is often difficult to know how results obtained from laboratory studies reflect the
natural world, particularly when the measured variable is survival, we repeated our study in both laboratory and field conditions.
Males drumming at the highest rate survived better than males drumming at a lower rate in both laboratory and field conditions.
These results are in accordance with the predictions of conditional-handicap models of sexual selection. Survival was independent
of male body mass and there was no significant correlation between male drumming activity and body mass. However, large males
moved further than smaller males, and males moving longer distances lost less mass than those moving shorter distances. These
results suggest that, moving, and consequently mate-searching activity, may be a condition-dependent trait and that there
may be a advantage for large males in mate searching.
Received: 22 October 1998 / Received in revised form: 28 January 1999 / Accepted: 14 February 1999 相似文献
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This research investigated the possibility of using recycled asphalt concrete as surface course in airport pavement. The basic properties of recycled asphalt binder after short- and long-term aging were firstly tested and compared with those of the virgin asphalt. Then, a series of laboratory tests were performed to evaluate the performance of recycled asphalt concrete (containing 40% and 70% RAP), in which the HMA mixture without RAP was used as a control. Furthermore, an experimental pavement consisting of three sections (corresponding to 0%, 40% and 70% RAP content) was constructed to verify the laboratory test results. These results indicated that the recycled asphalt could achieve the similar properties against long-term aging as virgin asphalt. Recycled asphalt concrete containing 40% RAP could be used as surface course in airport pavement as it exhibited similar performance as control mixture both from the laboratory and experimental pavement test results. On the contrary, recycled asphalt concrete containing 70% RAP was not recommended as its fatigue property was much poorer compared with that of virgin asphalt mixture. 相似文献
44.
环境监测实验室信息管理系统的构建与实施 总被引:3,自引:3,他引:3
沈艺 《环境监测管理与技术》2006,18(4):4-6
阐述了环境监测实验室信息管理系统(LIMS)的构建目标,介绍了系统的业务流程、总体设计及实施条件.提出建立环境监测LIMS系统,可提高分析数据的准确性和质量管理水平,全面提升实验室信息运转效率和管理水平,更好地为环境管理服务. 相似文献
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简要分析化验室采样过程中存在的问题,并就如何对石化化验室采样过程实行HSE管理提出一些具体的管理办法。 相似文献
48.
以射阳县环境监测站通过合并评审为例,分析了合并评审的社会环境、政策环境,阐述了合并评审应注意的4个环节,对基层环境监测、计量认证和实验室认可的合并评审工作,具有一定的借鉴价值. 相似文献
49.
Estimating the Effect of Protected Lands on the Development and Conservation of Their Surroundings 总被引:1,自引:0,他引:1
ROBERT I. McDONALD †† CHRIS YUAN-FARRELL† CHARLES FIEVET‡ MATTHIAS MOELLER§ PETER KAREIVA† DAVID FOSTER TED GRAGSON‡ ANN KINZIG§ LAUREN KUBY CHARLES REDMAN 《Conservation biology》2007,21(6):1526-1536
Abstract: The fate of private lands is widely seen as key to the fate of biodiversity in much of the world. Organizations that work to protect biodiversity on private lands often hope that conservation actions on one piece of land will leverage the actions of surrounding landowners. Few researchers have, however, examined whether protected lands do in fact encourage land conservation nearby or how protected lands affect development in the surrounding landscape. Using spatiotemporal data sets on land cover and land protection for three sites (western North Carolina, central Massachusetts, and central Arizona), we examined whether the existence of a protected area correlates with an increased rate of nearby land conservation or a decreased rate of nearby land development. At all sites, newly protected conservation areas tended to cluster close to preexisting protected areas. This may imply that the geography of contemporary conservation actions is influenced by past decisions on land protection, often made for reasons far removed from concerns about biodiversity. On the other hand, we found no evidence that proximity to protected areas correlates with a reduced rate of nearby land development. Indeed, on two of our three sites the development rate was significantly greater in regions with more protected land. This suggests that each conservation action should be justified and valued largely for what is protected on the targeted land, without much hope of broader conservation leverage effects. 相似文献
50.
Chemical characteristics and sources of water-soluble organic aerosol in southwest suburb of Beijing
Ruolan Hu Qingcheng Xu Shuxiao Wang Yang Hu Noshan Bhattarai Jingkun Jiang Yu Song Kaspar R. Daellenbach Lu Qi Andre S.H. Prevot Jiming Hao 《环境科学学报(英文版)》2020,32(9):99-110
PM2.5 filter sampling and components measurement were conducted in autumn and winter from 2014 to 2015 at a suburban site (referred herein as “LLH site”) located in the southwest of Beijing. The offline aerosol mass spectrometry (offline-AMS) analysis and positive matrix factorization (PMF) were applied for measurement and source apportionment of water-soluble organic aerosol (WSOA). Organic aerosol (OA) always dominated PM2.5 during the sampling period, especially in winter. WSOA pollution was serious during the polluted period both in autumn (31.1 µg/m3) and winter (31.9 µg/m3), while WSOA accounted for 54.4% of OA during the polluted period in autumn, much more than that (21.3%) in winter. The oxidation degree of WSOA at LLH site was at a high level (oxygen-to-carbon ratio, O/C=0.91) and secondary organic aerosol (SOA) contributed more mass ratio of WSOA than primary organic aerosol (POA) during the whole observation period. In winter, coal combustion OA (CCOA) was a stable source of OA and on average accounted for 25.1% of WSOA. In autumn, biomass burning OA (BBOA) from household combustion contributed 38.3% of WSOA during polluted period. In addition to oxygenated OA (OOA), aqueous-oxygenated OA (aq-OOA) was identified as an important factor of SOA. During heavy pollution period, the mass proportion of aq-OOA to WSOA increased significantly, implying the significant SOA formation through aqueous-phase process. The result of this study highlights the concentration on controlling the residential coal and biomass burning, as well as the research needs on aqueous chemistry in OA formation. 相似文献