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31.
The parameters and the measurement procedures described in this paper are seen as being part of the first stage in development of the human environment assessment process. Additional parameters need to be identified, and methods of measuring impacts reflected by the parameters must be developed and refined. Considerations of the human environment and those elements of the natural environment that are of importance to people must be included as an integral part of the environmental impact assessment process. Therefore, there is a need for continuing to identify parameters of the human environment and to develop methods of measuring impacts so that these considerations will become a well-integrated part of the environmental impact assessment process.  相似文献   
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As part of two large heart surveys, associations between traffic noise exposure and cardiovascular risk factors were studied. The Caerphilly sample (small town, total sample) consisted of 2512 men aged 45 to 59 years and the Speedwell sample (suburb of a major city, random sample) of 2030 men of same age group. Both studies have a prospective design; cross-sectional results are presented here. Acoustic measurements were carried out in both areas. Among the possible risk factors for ischaemic heart disease studied were blood pressure, blood coagulation, blood lipids and other biochemical factors. Statistically significant noise effects were detected for systolic blood pressure, total cholesterol, HDL cholesterol, total triglycerides, blood viscosity, platelet count and glucose level, although not all of these were consistent with noise being a risk factor for heart disease. In a subsample, the additional influence of work noise as determined by noise dosimetry was studied in 255 men, taking the use of ear protection into account. The associations between traffic noise and risk factors were more pronounced in men who also were exposed to high work noise levels.  相似文献   
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ABSTRACT: After 25 years of operation on ephemeral streams in the semiarid Southwest, this supercritical flume has provided more than 350 station-years of reliable streamflow data, even under freezethaw conditions experienced at elevations of 1,500 to 2,100 m, in Arizona. The flume has also provided streamflow data during flood periods produced by high intensity summer thunderstorm conditions, where considerable sediment and other debris was moved downstream.  相似文献   
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A series of mesocosms was exposed to a suite of light treatments and nutrient enrichment in order to generate algal communities of varying biomass. the influence of this biomass on the speciation of copper (II) was studied. Distribution coefficients (Kd,Lkg-1) were relatively high (logKd = 5 to 7), indicative of robust trace metal sequestration, and were likely controlled by the particulate organic carbon content (foc). Differences in Kd over time and among treatments were significant, as was the relationship between Kd and foc. Fluorescence quenching was used to determine binding capacities (Lt, M) and their associated binding constants (Kcond,M-1) in order to model the solid phase copper speciation. the Kcond ranged between 2.1 and 5.2 × 1012M-1, indicating a very strong copper-ligand complex, and was higher in mesocosms that received more light. the light Lt increased over time, dramatically after the nutrient enrichment, but did not vary systematically among light treatments. Lt ranged from 7.2 × 10- 7 to 4.9 × 10- 5 M. the large magnitudes of Kd, Kcond and Lt ensured that greater than 97% of total copper in the mesocosms was complexed by organic matter. the total copper concentration ([Cu]T, M) needed to reach a target dissolved copper concentration of 10-12.5 M (pCu = 12.5) was determined for each mesocosm over time. [Cu]T was between 8.02 × 10-5 and 3.41 × 10-2 M, and increased over time. the [Cu]T normalized to the target pCu (Effective Dose Ratio, EDR) increased directly with increases in algal biomass, indicating a direct link between system productivity and copper exposure. Approximately 45% of the variance in EDR was explained by variance in total biomass, while the residual variance in EDR was due likely to differences in the strengths of particle associations and magnitude of binding capacities.  相似文献   
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ABSTRACT

Air and precipitation samples were collected along an urban to over-water to rural transect across the northern Chesapeake Bay as a preliminary investigation into the spatial extent of elevated atmospheric concentrations of urban-derived persistent organic pollutants. Air samples were collected daily from June 3–9, 1996, along the transect as part of the Atmospheric Exchange over Lakes and Oceans project. Total (gas + particle bound) atmospheric polycy-clic aromatic hydrocarbon concentrations [∑-PAH] ranged from 0.4 to 114 ng/m3, and gas phase polychlorinated bi-phenyl concentrations [∑-PCB] ranged from 0.02 to 3.4 ng/m3. Strong concentration gradients were found for both PAHs and PCBs, with the highest concentrations in the city and the lowest at the downwind rural site. Gas and particle bound PAHs varied independently in the city, possibly due to strong but geographically separated emission sources. A precipitation event collected during westerly winds contained fourfold higher ∑-PAH and twelvefold higher ∑-PCB concentrations at the over-water site than at the rural background location, further indicating that the urban plume extends from Baltimore, MD, over the northern Chesapeake Bay over a spatial scale of approximately 30 km.  相似文献   
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The earliest measurements of benz[α]pyrene (BαP) in air samples were almost exclusively based on chroma-tography on alumina columns followed by ultraviolet absorption, in spite of the fact that the original discovery and isolation of BαP in coal tar was based on its fluorescence properties. With the increasing use of fluorescence techniques, the vastly increased sensitivity over ultraviolet measurements has become generally apparent. In air sample extracts containing the four polycyclics, benzo[a]pyrene (BαP) benzo[k]-fluoranthene (BkF), benzo[g,h,i]perylene, (BghiP), and BαP, ultraviolet measurements for BαP are particularly, inaccurate. Fluorescence measurements of BαP are much more accurate, but some improvement in accuracy seems desirable. The present work deals with improvement of the fluorescence measurement of BαP. It now is possible to measure BαP in the presence of BkF with greatly increased accuracy. Interferences resulting from the presence of benzo[k]fluoranthene are now much lower.  相似文献   
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Vegetation and soil surveys were conducted on metalliferous mine wastes in the northern and southern Pennines of England. Analyses of vegetation composition in relation to soil chemical variation were performed. Ordination analysis facilitated the detection of groups of co-occurring species which are characteristic of types of metal-contaminated soil. The results of regression analysis implied the importance of soil pH and concentration of available lead or zinc, depending upon region, in determining species distributions. A strong interactive effect was evident between soil phosphorus and zinc content in influencing species distributions in the southern Pennines sample.Regional similarities in the vegetation of apparently similar metalliferous soils existed. The unusually high species richness of some soils was associated with relatively low concentrations of heavy metals. Many species of relatively floristically-rich wastes were also colonists of surrounding grasslands or woodland. This indicated the potential importance of propagule availability and capability for rapid establishment on bare or unstable ground. Mechanisms of physiological stress avoidance, rather than heavy-metai tolerance, may explain the occurrence of non-metallophytes on soils contaminated with lead and zinc.  相似文献   
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