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151.
BACKGROUND: The purpose was to study the test-retest reliability and internal consistency of questions in a questionnaire concerning working conditions and health and the inter-rater reliability of observations and measurements according to an ergonomic checklist. METHOD: Fifty-seven operators participated in a retest questionnaire and 58 operators participated in an inter-observer test. RESULTS: The questions had fair to good or higher reliability in 142 of the total of 312. Twenty-seven of the total of 44 variables in the ergonomic checklist were classified as having fair to good or higher reliability. CONCLUSIONS: About half of the questions had fair to good or higher reliability and can be recommended for further analyses. The majority of variables in the ergonomic checklist were classified as having fair to good or higher reliability. Low reliability does not necessarily indicate that the reliability of the test, per se, is low but may signify that the conditions measured vary over time or that the answers are aggregated in one part of the scale.  相似文献   
152.
Summary Citing topical international instances the author demonstrates that environmental impoverishment is a major cause for tension and hostilities between nations. He makes a strong case that an assessment of security concepts should include a measure of environmental and resource-based stability.Few threats to peace and survival of the human community are greater than those posed by the prospects of cumulative and irreversible degradation of the biosphere on which human life depends. In a global context, true security cannot be achieved by mounting buildup of weapons (defense in a narrow sense), but only by providing basic conditions for solving non-military problems which threaten them. Our survival depends not only on military balance, but on global cooperation to ensure a sustainable biological environment.Report of the Brandt Commission, 1980Dr Norman Myers is a consultant in environment and development. He is a prolific author and served as the General Editor toThe GaiaAtlas of Planet Management (1985). In 1983, Dr Myers was awarded the World Wildlife Fund Gold Medal for his work on conservation.  相似文献   
153.
154.
This study investigates the application of models traditionally used to estimate erosion and sediment deposition to assess the potential risk of water quality impairment resulting from metal-bearing materials related to mining and mineralization. An integrated watershed analysis using Geographic Information Systems (GIS) based tools was undertaken to examine erosion and sediment transport characteristics within the watersheds. Estimates of stream deposits of sediment from mine tailings were related to the chemistry of surface water to assess the effectiveness of the methodology to assess the risk of acid mine-drainage being dispersed downstream of abandoned tailings and waste rock piles. A watershed analysis was preformed in the Patagonia Mountains in southeastern Arizona which has seen substantial mining and where recent water quality samples have reported acidic surface waters. This research demonstrates an improvement of the ability to predict streams that are likely to have severely degraded water quality as a result of past mining activities.  相似文献   
155.
Warning systems with the ability to predict floods several days in advance have the potential to benefit tens of millions of people. Accordingly, large‐scale streamflow prediction systems such as the Advanced Hydrologic Prediction Service or the Global Flood Awareness System are limited to coarse resolutions. This article presents a method for routing global runoff ensemble forecasts and global historical runoff generated by the European Centre for Medium‐Range Weather Forecasts model using the Routing Application for Parallel computatIon of Discharge to produce high spatial resolution 15‐day stream forecasts, approximate recurrence intervals, and warning points at locations where streamflow is predicted to exceed the recurrence interval thresholds. The processing method involves distributing the computations using computer clusters to facilitate processing of large watersheds with high‐density stream networks. In addition, the Streamflow Prediction Tool web application was developed for visualizing analyzed results at both the regional level and at the reach level of high‐density stream networks. The application formed part of the base hydrologic forecasting service available to the National Flood Interoperability Experiment and can potentially transform the nation's forecast ability by incorporating ensemble predictions at the nearly 2.7 million reaches of the National Hydrography Plus Version 2 Dataset into the national forecasting system.  相似文献   
156.
We investigated dissipation and sorption of atrazine, terbuthylazine, bromacil, diazinon, hexazinone and procymidone in two contrasting New Zealand soils (0–10 cm and 40–50 cm) under controlled laboratory conditions. The six pesticides showed marked differences in their degradation rates in both top- and subsoils, and the estimated DT50 values for the compounds were: 19–120 (atrazine), 10–36 (terbuthylazine), 12–46 (bromacil), 7–25 (diazinon), 8–92 (hexazinone) and 13–60 days for procymidone. Diazinon had the lowest range for DT50 values, while bromacil and hexazinone gave the highest DT50 values under any given condition on any soil type. Batch derived effective distribution coefficient (K d eff) values for the pesticides varied markedly with bromacil and hexazinone exhibiting low sorption affinity for the soils at either depth, while diazinon gave high sorption values. Comparison of pesticide degradation in sterile and non-sterile soils suggests that microbial degradation was the major dissipation pathway for all six compounds, although little influence of abiotic degradation was noticeable for diazinon and procymidone.  相似文献   
157.
Costs for as many as seven SO2 control technologies were determined for each of the 66 existing or planned coal-fired utility units in the state of Illinois, and projected operations for each unit from 1983 through the year 2000 were obtained from production cost modeling runs or other data. The Sulfur Dioxide Emission Reduction Optimization Program (SEROP), a utility-specific marginal cost pollution control model developed at Wisconsin Power and Light Co., was used to calculate annual marginal control cost data for each individual utility, and statewide aggregate data. The potential market in emission reduction credits (ERC) was then analyzed for three acid deposition control strategies. It was determined that emissions trading sufficient to meet targeted emission levels for acid deposition control in an economically efficient manner will not occur under any of the strategies unless the desire for utilities to maintain control of their ERCs in future years is taken into account. This can only be accomplished in one of two ways: 1) leasing of ERCs, or 2) a “contingent” sale where the buyer agrees to sell back the ERC after a specified period of time. Other factors affecting the feasibility of ERC leasing are discussed.  相似文献   
158.
To put waste-to-energy (WTE) in perspective, it is important to see how it measures up environmentally to other power generation utility sources.

This paper compares actual WTE facility emissions with those from fossil fuel combustion utility sources. This comparison is made on an electricity production basis, such as a pound of pollutant per megawatt-hour of net electricity generated, for each power generation source.  相似文献   
159.
BACKGROUND: Call centres (CCs) are among the most rapidly growing forms of workplaces in Sweden. The purpose of the study was to describe and compare working conditions between operators at internal and external CC companies and work tasks of different complexity. METHOD: A questionnaire was answered by 1183 operators, 848 women and 335 men, from 28 different CCs. The questionnaire covered background factors, employment, working hours and remuneration, call logging and monitoring, duties, computer work and workplace design during the previous month. RESULTS: Operators at external companies and operators with low-complexity work tasks were younger, more often employed by the hour and worked on a varying roster. They spent longer time on customer calls and had less varied tasks. Additional remuneration, call logging and monitoring were more common at external companies and among operators with low-complexity work tasks. CONCLUSION: The working conditions varied between internal and external CCs. There was also a variation in working conditions between work tasks of different complexity. There were aspects of supervision style and organization of work at CCs, especially at external ones and those with low-complexity tasks that could introduce stress and lack of well being among the staff.  相似文献   
160.
Abstract: The summertime heating of runoff in urban areas is recognized as a common and consistent urban climatological phenomenon. In this study, a simple thermal urban runoff model (TURM) is presented for the net energy flux at the impervious surfaces of urban areas to account for the heat transferred to runoff. The first step in developing TURM consists of calculating the various factors that control how urban impervious areas absorb heat and transfer it to moving water on the surface. The runoff temperature is determined based on the interactions of the physical characteristics of the impervious areas, the weather, and the heat transfer between the moving film of runoff and the impervious surface common in urban areas. Key surface and weather factors that affect runoff temperature predictions are type of impervious surface, air temperature, humidity, solar radiation before and during rain, rainfall intensity, and rainfall temperature. Runoff from pervious areas is considered separately and estimated using the Green‐Ampt Mein‐Larson rainfall excess method. Pervious runoff temperature is estimated as the rainfall temperature. Field measurements indicate that wet bulb temperature can be used as a surrogate for rainfall temperature and that runoff temperatures from sod average just 2°C higher than rainfall temperatures. Differences between measured and predicted impervious runoff temperature average approximately 2°C, indicating that TURM is a useful tool for determining runoff temperatures for typical urban areas.  相似文献   
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