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381.
382.
Nonparametric conditional density estimation in a deep learning framework for short-term forecasting
Huberman David B. Reich Brian J. Bondell Howard D. 《Environmental and Ecological Statistics》2022,29(4):677-704
Environmental and Ecological Statistics - Short-term forecasting is an important tool in understanding environmental processes. In this paper, we incorporate machine learning algorithms into a... 相似文献
383.
Islam Md.Monirul Ali Md.Idris Ceh Brian Singh Sanjeet Khan Muhammad Kamran Dagar Vishal 《Environmental science and pollution research international》2022,29(23):34231-34247
Environmental Science and Pollution Research - Energy consumption for sustainable development has become a crucial issue in recent years. The anthropogenic effects of traditional energy sources... 相似文献
384.
Starlings were collected for the National Pesticides Monitoring Program from 112 sites throughout the contiguous United States and analyzed for organochlorine compounds. Starling samples from 14 sites had greater than 1.0 ppm DDE residues with the highest DDE level being 15.8 ppm in a sample taken near Roswell, New Mexico. The occurrence of PCBs and chlordane isomers increased since the 1976 collection, but DDT, DDE, and dieldrin occurrence decreased. DDE and dieldrin levels decreased since the 1976 collection, but the level of PCBs has increased. 相似文献
385.
Introduction
Police records are the most common source of data used to estimate motor-vehicle collision risks, understand causal or contributing factors, and evaluate the efficacy of interventions. The literature notes concerns about this information citing discrepancies between police reports and other sources of injury occurrence and severity data. The primary objective of the analysis was to assess the adequacy of police reports for an examination of weather-related injury collision risk.Method
Analyses of relative risk were carried out using both police records and comprehensive insurance claim data for Winnipeg, Canada over the period 1999-2001.Results and conclusions
Both data sets yielded very similar results—precipitation substantially increases the risk of injury collision (police records: RR 1.76, CI 1.55-2.00; insurance: RR 1.80, CI 1.62-1.99) and risk of injury (police records, RR 1.74, CI 1.55-1.96; insurance, RR 1.69, CI 1.55-1.85) relative to corresponding dry weather control periods. Both rainfall and snowfall were associated with large increases in collisions and injuries.Impact on Industry
While relative risks are almost identical, over 64% more injury collisions and 74% more injuries were identified using the insurance data, which is an important difference for evaluating absolute risk and exposure. 相似文献386.
Mayumi Allinson Brian Williams Graeme Allinson Michelle Graymore Frank Stagnitti 《毒物与环境化学》2013,95(3-4):401-414
Dithianon formulations are unstable in slightly basic aqueous solutions (pH 9, 20°C, t ½ = 5.6 h) but relatively stable in neutral or acidic solution (pH 4,20°C, t ½ = 6443 h). To ensure the efficacy of this fungicide it is important to prepare the spray mix fresh with neutral or slightly acidic water. Dithianon is unstable towards natural sunlight in the solid and aqueous phase, with half‐lives of approximately 68 and 42 days, respectively. Thermal hydrolysis does not seem to be the preferred degradation pathway when aqueous solutions are heated by the South Australian summer sun. The major aqueous phase photodegradation product has been identified as 2,3‐dihydro‐1,4‐dithiaanthraquinone. These results strongly suggest that should dithianon be accidentally released into basic Australian waters then it is likely to be rapidly chemically hydrolysed and pose little long term environmental threat. However, dithianon is only slowly chemically and photo‐lytically hydrolysed in neutral and acidic waters, and in this case accidentally release may pose a significant short term environmental threat. 相似文献
387.
Habitat protection, creation and management are at the forefront of nature conservation throughout the world. Many terrestrial and marine ecosystems are under pressure from a diverse range of issues including impacts associated with climate change, multiple resource use and increased development. Saltmarsh within the United Kingdom, is one such valuable habitat which has suffered significant losses over the last eighty or so years. Any environmental management practice or decision applied to these areas, should ideally be based on evidence of processes and change. One potential way of measuring saltmarsh change is by using historical maps and aerial photographs to look for patterns of growth or reduction. This research examines the process of saltmarsh mapping and compares historical aerial photographs and maps to assess their suitability for habitat change assessment. This research suggests that whilst historical aerial photography can be accessed and utilised effectively, the data presented on maps should be treated with a great deal of caution. The saltmarsh represented on the maps used in this research was noticeably different from that mapped using aerial photographs from a similar time period. Whilst this does not dismiss the use of historic maps along this part of the coast, it does suggest they should be treated with some degree of caution and will vary in their reliability. 相似文献
388.
Sturtevant BR Miranda BR Shinneman DJ Gustafson EJ Wolter PT 《Ecological applications》2012,22(4):1278-1296
Insect disturbance is often thought to increase fire risk through enhanced fuel loadings, particularly in coniferous forest ecosystems. Yet insect disturbances also affect successional pathways and landscape structure that interact with fire disturbances (and vice-versa) over longer time scales. We applied a landscape succession and disturbance model (LANDIS-II) to evaluate the relative strength of interactions between spruce budworm (Choristoneura fumiferana) outbreaks and fire disturbances in the Boundary Waters Canoe Area (BWCA) in northern Minnesota (USA). Disturbance interactions were evaluated for two different scenarios: presettlement forests and fire regimes vs. contemporary forests and fire regimes. Forest composition under the contemporary scenario trended toward mixtures of deciduous species (primarily Betula papyrifera and Populus spp.) and shade-tolerant conifers (Picea mariana, Abies balsamea, Thuja occidentalis), with disturbances dominated by a combination of budworm defoliation and high-severity fires. The presettlement scenario retained comparatively more "big pines" (i.e., Pinus strobus, P. resinosa) and tamarack (L. laricina), and experienced less budworm disturbance and a comparatively less-severe fire regime. Spruce budworm disturbance decreased area burned and fire severity under both scenarios when averaged across the entire 300-year simulations. Contrary to past research, area burned and fire severity during outbreak decades were each similar to that observed in non-outbreak decades. Our analyses suggest budworm disturbances within forests of the BWCA have a comparatively weak effect on long-term forest composition due to a combination of characteristics. These include strict host specificity, fine-scaled patchiness created by defoliation damage, and advance regeneration of its primary host, balsam fir (A. balsamea) that allows its host to persist despite repeated disturbances. Understanding the nature of the three-way interaction between budworm, fire, and composition has important ramifications for both fire mitigation strategies and ecosystem restoration initiatives. We conclude that budworm disturbance can partially mitigate long-term future fire risk by periodically reducing live ladder fuel within the mixed forest types of the BWCA but will do little to reverse the compositional trends caused in part by reduced fire rotations. 相似文献
389.
Refaul FerdousFaisal Khan Rehan SadiqPaul Amyotte Brian Veitch 《Journal of Loss Prevention in the Process Industries》2012,25(1):8-19
Bow-tie analysis is a fairly new concept in risk assessment that can describe the relationships among different risk control parameters, such as causes, hazards and consequences to mitigate the likelihood of occurrence of unwanted events in an industrial system. It also facilitates the performance of quantitative risk analysis for an unwanted event providing a detailed investigation starting from basic causes to final consequences. The credibility of quantitative evaluation of the bow-tie is still a major concern since uncertainty, due to limited or missing data, often restricts the performance of analysis. The utilization of expert knowledge often provides an alternative for such a situation. However, it comes at the cost of possible uncertainties related to incompleteness (partial ignorance), imprecision (subjectivity), and lack of consensus (if multiple expert judgments are used). Further, if the bow-tie analysis is not flexible enough to incorporate new knowledge or evidence, it may undermine the purpose of risk assessment.Fuzzy set and evidence theory are capable of characterizing the uncertainty associated with expert knowledge. To minimize the overall uncertainty, fusing the knowledge of multiple experts and updating prior knowledge with new evidence are equally important in addition to addressing the uncertainties in the knowledge. This paper proposes a methodology to characterize the uncertainties, aggregate knowledge and update prior knowledge or evidence, if new data become available for the bow-tie analysis. A case study comprising a bow-tie for a typical offshore process facility has also been developed to describe the utility of this methodology in an industrial environment. 相似文献
390.
This research compares two existing methodologies, mixed trophic impact analysis and utility analysis, which use network analysis to evaluate the direct, pair-wise, and indirect, holistic, ecological relations between ecosystem compartments. The two approaches have many similarities, but differ in some key assumptions which affect both the final results and interpretations. Here, we briefly introduce both methodologies through a series of two simple examples; a 3-compartment competition model and a 3-compartment food chain model, and then apply the methodologies to a 15-compartment ecosystem model of the Chesapeake Bay. This example demonstrates how implementing the various conceptual and methodological assumptions lead to differing results. Notably, the overall number of positive relations is greatly affected by the treatment of the self-interactions and the handling of detritus compartments lead to a distinction between ecological or trophic relations. We recommend slight changes to both methodologies, not necessarily in order to bring them completely together, but because each has some points which are stronger and better defensible. 相似文献