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181.
We first identify six primary problems with conventional practice: lack of context, inadequate participation from aboriginal communities, exclusion of important losses, reliance on market-based measures, neglect of uncertainty, and inadequate treatment of time. We then propose a different approach to compensation, based on insights from the decision sciences and structured decision making. Using case-study examples, we discuss how the proposed approach might address common sources of cultural loss and, in a concluding section, summarize some of the implications for compensation agreements and for environmental management practices.  相似文献   
182.
Four populations of the native annual grassTriplasis purpurea were surveyed on coastal beaches along the south shore of Staten Island, NY, to determine the potential of this species to colonize shoreline habitats mostly devoid of other vegetation. If the species can establish and maintain dense populations, it may have conservation value for urban beaches disturbed by human activities. For two populations, survivorship, growth, and reproduction were monitored at different distances from shore to determine the ability of this species to maintain viable populations. At three sites,T. purpurea occurred in >75% of all quadrats and the highest density was 1195 plants/m2 at 74 m from shore in one recently disturbed site. Density generally increased with increasing distances from shore at low tide (from ca. 40 – 90 m). Plants showed the greatest growth and reproduction at close distances to shore (30 – 40 m); part of this effect was due to density in one population, but when density effects were removed statistically, there still remained a decline in growth and reproduction with increasing distance from shore. Improved vigor nearest to shore may be due to continual sand deposition. Survivorship showed a Type I pattern, with low mortality throughout the growing season. By colonizing newly-deposited and continually shifting sands,T. purpurea can contribute to the earliest stages of ecological succession along disturbed beaches in eastern North America and may be valuable to the development and management of urban coastal plant communities.  相似文献   
183.
Four populations of the native annual grassTriplasis purpurea were surveyed on coastal beaches along the south shore of Staten Island, NY, to determine the potential of this species to colonize shoreline habitats mostly devoid of other vegetation. If the species can establish and maintain dense populations, it may have conservation value for urban beaches disturbed by human activities. For two populations, survivorship, growth, and reproduction were monitored at different distances from shore to determine the ability of this species to maintain viable populations. At three sites,T. purpurea occurred in >75% of all quadrats and the highest density was 1195 plants/m2 at 74 m from shore in one recently disturbed site. Density generally increased with increasing distances from shore at low tide (from ca. 40–90 m). Plants showed the greatest growth and reproduction at close distances to shore (30–40 m); part of this effect was due to density in one population, but when density effects were removed statistically, there still remained a decline in growth and reproduction with increasing distance from shore. Improved vigor nearest to shore may be due to continual sand deposition. Survivorship showed a Type I pattern, with low mortality throughout the growing season. By colonizing newly-deposited and continually shifting sands,T. purpurea can contribute to the earliest stages of ecological succession along disturbed beaches in eastern North America and may be valuable to the development and management of urban coastal plant communities.  相似文献   
184.
Two dense nonaqueous phase liquid (DNAPL) tracer tests werecarried out in a shallow aquifer north of Fort Worth, TX. i-Propanolwas used as the nonpartitioning tracer; n-hexanol and n-octanol werethe partitioning tracers. Field data, mathematical modeling, theresults of column tests, and field tracer tests with NaCl were usedin designing the DNAPL tracer tests. The results indicated the presenceof DNAPL at both sites tested; semi-quantitative estimates of theamounts of DNAPL present were obtained by mathematical modeling.Interpretation was complicated by heterogeneity of the aquifer andmass transport effects.  相似文献   
185.
PROBLEM: Although parking facilities are a common feature of the landscape in the United States, little is known about their safety. METHOD: A dataset of parking lot fatalities for 1993-2002, created from the Census of Fatal Occupational Injury (CFOI) research file, was analyzed. RESULTS: The most common events in parking lots were contact with objects (15%), pedestrian fatalities (13%), homicides (36%), and suicides (11%). The perpetrators of parking lot fatalities, compared to all workplace homicides, were more likely to be known to the victim. CONCLUSION: The 206 work-related fatalities per year in parking lots present challenges to the safety community. Although much of the risk results from the usage of motor vehicles, violent acts are even more prominent. IMPACT ON INDUSTRY: Because homicides are most prevalent in parking lots, both administrative and environmental measures may lower the risk of homicide. Although difficult to assess, various elements of the design of parking facilities may have an influence on the occurrence of injuries.  相似文献   
186.
This study evaluates the importance of geologic and geographic factors in constraining the location of limestone mining operations for the production of cement in the Great Lakes region of the United States. Cities and their infrastructure require abundant cement, which is manufactured from limestone and other quarry products, but expansion of cities limits the locations of these operations. Possible locations of limestone and cement operations are controlled by geologic factors including distribution and mineralogy of geologic formations as well as depth of overburden, and geographic factors including location of wetlands, cities, and other surface features that preclude development of quarries and manufacturing operations. Overlay analysis was used to evaluate the importance of these factors. Results show that, although limestone underlies about a third of the region, almost 50 percent of this limestone is unavailable for quarrying due to coverage by the built environment, protected natural areas, or excessive overburden thickness. When characteristics such as limestone quality are also accounted for, accessible resources shrink to as little as 2 percent of the total land area. Although the remaining 2 percent of land area may supply local needs for some years, geologic factors clearly must be included in long-term regional land use planning.  相似文献   
187.
Lomonte C  Gregory D  Baker AJ  Kolev SD 《Chemosphere》2008,72(10):1420-1424
The re-use of biosolids is becoming increasingly popular for land applications. However, biosolids may contain elevated levels of metals and metalloids (including mercury) relative to background environmental concentrations. Consequently, reliable mercury analysis is important to allow classification of biosolids and to determine appropriate options for beneficial uses. This paper reports on a comparative study of 12 hotplate wet digestion methods for their suitability for the determination of mercury in biosolids. The methods were applied to mercury biosolids samples from four localities of two different sewage treatment plants in the State of Victoria, Australia. Samples were also spiked with methylmercury chloride and mercury sulphide to evaluate the Hg recovery in each hotplate digestion method. Aqua regia (HCl:HNO(3)=3:1), reverse aqua regia (HCl:HNO(3)=1:3), nitric, hydrochloric, sulphuric acid and their combinations with or without hydrogen peroxide were studied as wet digestion solutions. The method providing the best mercury recoveries was optimized. Under optimal conditions the corresponding analytical procedure consisted of 1h pre-digestion of 0.4 g biosolids sample with 10 ml reverse aqua regia with temperature increasing to 110 degrees C and 3h digestion at this temperature. In the last 10 min of the digestion step, 2 ml hydrogen peroxide were added to ensure complete decomposition of all mercury containing compounds. After filtering and dilution with deionised water (1:10), the concentration of mercury was determined by cold vapour atomic absorption spectrometry. It is expected, that the wet acid digestion method developed in this study will be also applicable to biosolids from other sewage treatment plants and to other types of solid mercury samples with elevated levels of organic matter.  相似文献   
188.
Axenic plantlets derived from three species of marine macroalgae, the temperate green alga Acrosiphonia coalita, the temperate red alga Porphyra yezoensis, and the tropical red alga Portieria hornemannii, all possessed a similar metabolic route to remove the explosive compound 2,4,6-trinitrotolune (TNT) from seawater. At a biomass density of 1.2 g l(-1) and initial TNT concentrations of 10 mg l(-1) or less, TNT removal from seawater was 100% within 72 h for P. hornemannii and P. yezoensis. Specific rate constants for TNT uptake were 0.016-0.018 l g(-1)FWh(-1) for A. coalita filaments, 0.047-0.062 l g(-1)FW h(-1) for P. yezoensis blades, and 0.037-0.049 l g(-1)FW h(-1) for P. hornemannii microplantlets. Only trace amounts of TNT were found within the biomass. All species reduced TNT to 2-amino-4,6-dinitrotoluene and 4-amino-2,6-dintrotoluene, but these products never accounted for more than 20% of the initial TNT.  相似文献   
189.
Two-photon resonance enhanced multiphoton ionization (REMPI) has been shown to be a unique ionization method for mass spectrometry, exhibiting both high sensitivity and chemical selectivity. Because REMPI is a gas-phase method, its applications have been limited either to direct analysis of vapor phase samples, or in conjunction with an initial laser desorption or other vaporization step. We describe here for the first time a combination of membrane introduction mass spectrometry (MIMS) and REMPI with time-of-flight mass spectrometry (TOF-MS), which allows for the direct analysis of trace amounts of organic compounds in water samples. The objective of our research was the detection of very low levels of aromatic contaminants, particularly benzene, toluene, and xylene (BTX), in aqueous solutions without interference due to the water. We have measured limits of detection (LOD) for selected aromatics in water below 1 part-per-trillion with an averaging time of less than 10 s using a continuous sample flow.  相似文献   
190.
The Department of Energy (DOE) is conducting a Comprehensive Environmental Response, Compensation and Liability Act (CERCLA) mandated Remedial Investigation/Feasibility Study for a site contaminated with Dense Non-Aqueous Phase Liquid (DNAPL) pollutants. Three key efforts were a hydrogeological modeling approach, the generation of feasible sequences of technologies, and the screening of alternative technologies. This research uses a decision analysis process to provide a quantitative assessment of the candidate technologies. Decision analysis modeling was used to gain insight into each sequence of technologies. Sensitivity analysis was also conducted to assess the impact of key assumptions. The results provided the DOE with an objective and traceable rationale for screening and reducing all of the potential technology combinations to 58 technology combinations and a method for identifying the top scoring combinations. The approach has wide applicability to similar CERCLA remediation efforts.  相似文献   
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