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391.
392.
Scientists, resource managers, and decision makers increasingly use knowledge coproduction to guide the stewardship of future landscapes under climate change. This process was applied in the California Central Valley (USA) to solve complex conservation problems, where managed wetlands and croplands are flooded between fall and spring to support some of the largest concentrations of shorebirds and waterfowl in the world. We coproduced scenario narratives, spatially explicit flooded waterbird habitat models, data products, and new knowledge about climate adaptation potential. We documented our coproduction process, and using the coproduced models, we determined when and where management actions make a difference and when climate overrides these actions. The outcomes of this process provide lessons learned on how to cocreate usable information and how to increase climate adaptive capacity in a highly managed landscape. Actions to restore wetlands and prioritize their water supply created habitat outcomes resilient to climate change impacts particularly in March, when habitat was most limited; land protection combined with management can increase the ecosystem's resilience to climate change; and uptake and use of this information was influenced by the roles of different stakeholders, rapidly changing water policies, discrepancies in decision-making time frames, and immediate crises of extreme drought. Although a broad stakeholder group contributed knowledge to scenario narratives and model development, to coproduce usable information, data products were tailored to a small set of decision contexts, leading to fewer stakeholder participants over time. A boundary organization convened stakeholders across a large landscape, and early adopters helped build legitimacy. Yet, broadscale use of climate adaptation knowledge depends on state and local policies, engagement with decision makers that have legislative and budgetary authority, and the capacity to fit data products to specific decision needs.  相似文献   
393.
394.
The experience from CO2 injection at pilot projects (Frio, Ketzin, Nagaoka, US Regional Partnerships) and existing commercial operations (Sleipner, Snøhvit, In Salah, acid-gas injection) demonstrates that CO2 geological storage in saline aquifers is technologically feasible. Monitoring and verification technologies have been tested and demonstrated to detect and track the CO2 plume in different subsurface geological environments. By the end of 2008, approximately 20 Mt of CO2 had been successfully injected into saline aquifers by existing operations. Currently, the highest injection rate and total storage volume for a single storage operation are approximately 1 Mt CO2/year and 25 Mt, respectively. If carbon capture and storage (CCS) is to be an effective option for decreasing greenhouse gas emissions, commercial-scale storage operations will require orders of magnitude larger storage capacity than accessed by the existing sites. As a result, new demonstration projects will need to develop and test injection strategies that consider multiple injection wells and the optimisation of the usage of storage space. To accelerate large-scale CCS deployment, demonstration projects should be selected that can be readily employed for commercial use; i.e. projects that fully integrate the capture, transport and storage processes at an industrial emissions source.  相似文献   
395.
This paper explores how the widely held public policy view of the evolution of the risk profile associated with geologic carbon dioxide (CO2) storage profoundly influences the public policy dialogue about how to best address the long-term risk profile for geologic storage. Evidence emerging from research and pilot scale field demonstrations of CO2 storage demonstrates that, with proper site characterization and sound operating practices, retention of stored CO2 will increase with time thus invalidating the premise of an ever growing risk. The authors focus on key issues of fit, interplay, and scalability associated with the ability of a trust fund funded by a hypothetical $1 per tonCO2 tipping fee for each ton of CO2 stored in the United States under WRE450 and WRE550 climate policies to manage such risks in an economically efficient and environmentally effective manner. The authors conclude there is no intrinsic value – in terms of risk management or risk reduction – in creating a trust fund predicated solely on collecting a universally applied tipping fee that does not take into account site-specific risk profiles. If left to grow unchecked, a trust fund that is predicated on a constant stream of payments unrelated to each contributing site's risk profile could result in the accumulation of hundreds of billions to more than a trillion dollars contributing to significant opportunity cost of capital. Further, rather than mitigating the financial consequences of long-term CCS risks, this analysis suggests a blanket $1 per tonCO2 tipping fee, if combined with a concomitant limitation of liability may increase the probability and frequency of long-term risk by eliminating financial incentives for sound operating behavior and site selection criteria—contribute to moral hazard. At a minimum, effective use of a trust fund requires: (1) strong oversight regarding site selection and fund management, and (2) a clear process by which the fund is periodically valued and funds collected are mapped to the risk profile of the pool of covered CCS sites. Without appropriate checks and balances, there is no a priori reason to believe that the amount of funds held in trust will map to the actual amount of funds needed to address long-term care expenses and delimited compensatory damages. For this reason, the authors conclude that financing a trust fund or other risk management instrument should be based on a site delimited estimate of potential future expected financial consequences rather than on the random adoption of a fixed funding stream, e.g., a blanket $1 per ton, because it “sounds” reasonable.  相似文献   
396.
Under stable stratification and light winds large horizontal wind direction fluctuations have been observed quite often leading to meandering of pollutants plume downwind of elevated point sources. Due to this plume meandering long term concentration levels can be reduced by a factor of 4 or more, compared to straight plume conditions. Some possible mechanisms causing plume meandering under stable conditions are discussed, including gravity waves and vortices with horizontal or vertical axis.  相似文献   
397.
A new sampling device is described for the simultaneous collection of NH3, HNO3, HCl, SO2 and H2O2 in ambient air. The apparatus is based on air sampling by two parallel annular denuder tubes. The gases are collected by absorption in solutions present in the annulus of the denuder tubes. After a sampling time of 30 min at flow rate of 32 ℓ min−1 the solutions are extracted from the denuders and analyzed off-line. The detection limits of NH3, HNO3, HCL and SO2 are in the order of 0.1–0.5 μm−3. For H2O2 the detection limit is 0.01 μm−3. The reproducibility is 5–10% at the level of ambient air concentrations. Comparison of this novel technique with existing methods gives satisfactory results. The compact set-up offers the possibility of field experiments without the need of extensive equipment.  相似文献   
398.
The design of lagoons for the dewatering and retention of ash from pulverised coal burned in a power plant in Hong Kong is described. To reduce pollution of nearby oyster beds the sea water used to convey the ash as a slurry is decanted and returned to the power plant for discharge into deep water.  相似文献   
399.
Efficient, cost effective measures for the safe disposal of hazardous wastes have been developed to meet the needs of industries in Brisbane and the surrounding area. Liquid hazardous wastes are neutralised, oxidised, or reduced as appropriate, and fixed (solidified) by the addition of fly-ash and cement kiln dust to form a material of the consistency of coarse gravel. Fixation is performed in cells dug in solid clay, holding about 70 tonnes. Fixed material containing pesticides, paints or organic solvents is left in the clay cells, capped with clay; fixed inorganics and waste oils having no toxic contaminants are used for land contouring on the site. Leachate tests on the latter have been uniformly below 10 times USEPA Drinking Water guidelines — that is, 10 times better than the limits nominated by the EP Leach Test (1980). Bores around the site have detected no leachates during the past seven years. A simple but effective management system keeps wastes segregated and confirms the identity of each batch of waste on receipt. All costs are charged to the waste generator including costs of correcting errors.  相似文献   
400.
The worst-case meteorological scenarios for the air pollution impact of coal-fired power stations located in tropical Australia are usually those of convective or seabreeze states. Under such conditions maximum hourly ground-level concentrations occur within 5 km of typical elevated sources and are potentially important unless either low sulphur coal is burnt (the usual situation for Australian coals) or restrictions are placed upon neighbouring land use. In such conditions even slightly complex surrounding terrain can cause major changes in surface and lower-level wind and turbulence characteristics, although the resultant effects on ground-level concentrations are probably relatively small. The monitoring data bases of an inland and a coastal power station in tropical Queensland give similar qualitative results to recent EPRI studies. Concurrent detailed meteorological measurements show that convective scaling techniques order both data sets in a satisfactory manner. The convective dispersion model of Spillane (1985, CSIRO internal report) has also shown more predictive skill than conventional approaches and emphasizes the importance of gathering vertical velocity statistics for most sites. Some of the forthcoming developments in related Australian dispersion work are outlined.  相似文献   
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