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This study examines how pre‐existing disabling conditions influenced the recovery process of survivors of Hurricane Katrina. It focuses specifically on the barriers that hindered the recovery process in these individuals. Focus groups were convened in four Gulf Coast states with 31 individuals with disabilities who lived in or around New Orleans, Louisiana, prior to Hurricane Katrina in August 2005. Qualitative data were analysed using grounded theory methodology. Five themes emerged as the most significant barriers to recovery: housing; transportation; employment; physical and mental health; and accessing recovery services. While these barriers to recovery were probably common to most survivors of the disaster, the research results suggest that disability status enhanced the challenges that participants experienced in negotiating the recovery process and in acquiring resources that accommodated their disabilities. The findings indicate that, when disaster recovery services and resources did not accommodate the needs of individuals with disabilities, recovery was hindered. Recovery efforts should include building accessible infrastructure and services that will allow for participation by all.  相似文献   
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O -deethylase (EROD) activity to a similar degree as PCB Aroclor 1254 and to a greater extent than PCT Aroclor 5460. The presence of high concentrations of PCTs contributed to the facility being included on the National Priorities List. It subsequently became the first US federal facility to sign a Federal Facility Agreement, identifying cleanup responsibilities, prior to formal listing.  相似文献   
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Most prior climate change assessments for U.S. agriculture have focused on major world food crops such as wheat and maize. While useful from a national and global perspective, these results are not particularly relevant to the Northeastern U.S. agriculture economy, which is dominated by dairy milk production, and high-value horticultural crops such as apples (Malus domestica), grapes (Vitis vinifera), sweet corn (Zea mays var. rugosa), cabbage (Brassica oleracea var. capitata), and maple syrup (sugar maple, Acer saccharum). We used statistically downscaled climate projections generated by the HadCM3 atmosphere–ocean general circulation model, run with Intergovernmental Panel on Climate Change future emissions scenarios A1fi (higher) and B1 (lower), to evaluate several climate thresholds of direct relevance to agriculture in the region. A longer (frost-free) growing season could create new opportunities for farmers with enough capital to take risks on new crops (assuming a market for new crops can be developed). However, our results indicate that many crops will have yield losses associated with increased frequency of high temperature stress, inadequate winter chill period for optimum fruiting in spring, increased pressure from marginally over-wintering and/or invasive weeds, insects, or disease, or other factors. Weeds are likely to benefit more than cash crops from increasing atmospheric carbon dioxide. Projections of thermal heat index values for dairy cows indicate a substantial potential negative impact on milk production. At the higher compared to lower emissions scenario, negative climate change effects will occur sooner, and impact a larger geographic area within the region. Farmer adaptations to climate change will not be cost- or risk-free, and the impact on individual farm families and rural communities will depend on commodity produced, available capital, and timely, accurate climate projections.  相似文献   
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Summary Atta colombica uses chemical mass recruitment that allows the rapid exploitation of resources. Most foragers thus search only within patches. Accumulation of extra foragers at patches results in sampling of alternate food items and area-restricted search as patch resources are depleted.Individual workers have a higher probability of removing a leaf fragment the earlier they arrive at a bait. Workers that arrive when much of the resource is gone travel further on the bait (within the patch) but do not spend significantly more time at the patch. They give up after 50–80s.Foraging effort is centered on the extensive trail system, not on the nest a predicted by time and energy foraging models. Search effort is also trail centered. The probability that an item will be discovered decreases with distance from the trail and increasing litter depth. Trail traffic and trail quality together mave no significant effect although this may be because they act antagonistically.Economic considerations predict that trials should be built to high quality and very productive sites. If trails are built as a result of recruitment and recruitment reflects patch quality and productivity, characteristics of forage sites are physically embodied in the trail system.Leaf cutter foraging is better understood as a long term optimization that effectively exploits resources over the lifetime of the colony than as prudent predation that husbands resources.  相似文献   
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Blue mussels (Mytilus edulis) were collected from coastal areas and voes in Shetland and Orkney during March and April 1998 and from various coastal locations around mainland Scotland and from the Islands during October and December 1999. The polycyclic aromatic hydrocarbon concentration and composition (2- to 6-ring parent and branched) were determined for all samples. Additional analysis, including sensory assessment and the determination of n-alkanes and geochemical biomarkers, was also undertaken on the Shetland and Orkney mussels collected in 1998. Mussels from Shetland and Orkney exhibited a wide range of total PAH concentration (14.7 to 7,177 ng g(-1) wet weight). Those mussels collected in 1999 exhibited a narrower concentration range. The lowest value (mussels from Loch Kentra) was 8.4 ng g(-1) wet weight while the maximum concentration was 344.1 ng g(-1) wet weight and was determined in mussels from Granton East in the Firth of Forth. The PAH concentration ratios in mussels from Dury Voe (Grunna), Long Hope and Kirkwall Bay were consistent with a predominately petrogenic source for these contaminants. This was supported by both the sensory assessment and the n-alkane and triterpane profiles. Comparisons of the PAH concentrations in mussels with sediments collected from the same locations around Shetland and Orkney showed that in areas of high sediment PAH concentration the bioavailability of these contaminants was limited.  相似文献   
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Fluorinated compounds (FC) are high-global warming potential (GWP) greenhouse gases used and emitted during the manufacture of silicon semiconductor devices. Following the U.S. EPA's PFC Emissions Vintage Model (PEVM), uncontrolled FC emissions are modeled as proportional to total manufactured layer area (TMLA) of silicon. FC emissions of World Semiconductor Council (WSC) charter member countries (Europe, Japan, Korea, Taiwan and the United States), which voluntarily committed in 1999 to lower FC emissions by 2010 to 10% of baseline year emissions, are modeled for the period 1995–2020. For this same period, emissions from Chinese manufacturers under alternative emission reduction scenarios are modeled. If Chinese manufacturers were to adopt a baseline year of 2005 and a reduction target of 10% below baseline year emissions to be achieved by 2020, emissions would be 3.4 MMTCO2eq, comparable to the similarly projected controlled emissions of an average WSC charter member country (=16.3/5 MMTCO2eq) in 2020. The relative stringency of the alternative reduction scenarios considered for China vary between 50 and 95% reduction compared to business as usual (BAU). This is comparable to the stringency of the WSC charter members’ goals for which FC emission reduction technologies are currently available.  相似文献   
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