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971.
There has been a concerted effort by the international scientific community to understand the multiple causes and patterns of land-cover change to support sustainable land management. Here, we examined biophysical suitability, and a novel integrated index of “Economic Pressure on Land” (EPL) to explain land cover in the year 2000, and estimated the likelihood of future land-cover change through 2050, including protected area effectiveness. Biophysical suitability and EPL explained almost half of the global pattern of land cover (R 2 = 0.45), increasing to almost two-thirds in areas where a long-term equilibrium is likely to have been reached (e.g. R 2 = 0.64 in Europe). We identify a high likelihood of future land-cover change in vast areas with relatively lower current and past deforestation (e.g. the Congo Basin). Further, we simulated emissions arising from a “business as usual” and two reducing emissions from deforestation and forest degradation (REDD) scenarios by incorporating data on biomass carbon. As our model incorporates all biome types, it highlights a crucial aspect of the ongoing REDD + debate: if restricted to forests, “cross-biome leakage” would severely reduce REDD + effectiveness for climate change mitigation. If forests were protected from deforestation yet without measures to tackle the drivers of land-cover change, REDD + would only reduce 30 % of total emissions from land-cover change. Fifty-five percent of emissions reductions from forests would be compensated by increased emissions in other biomes. These results suggest that, although REDD + remains a very promising mitigation tool, implementation of complementary measures to reduce land demand is necessary to prevent this leakage.  相似文献   
972.
Temporal trends of polyfluoroalkyl compounds (PFCs) were examined in grey seal (Halichoerus grypus) liver from the Baltic Sea over a period of 35 years (1974-2008). In total, 17 of 43 PFCs were found, including the perfluoroalkyl sulfonates (C4-C10 PFSAs), perfluorooctanesulfinate (PFOSi), long chain perfluoroalkyl carboxylates (C7-C14 PFCAs), and perfluoroalkyl sulfonamides (i.e., perfluorooctane sulfonamide (FOSA) and N-ethyl perfluorooctane sulfonamide (EtFOSA)), whereas saturated and unsaturated fluorotelomer carboxylates, shorter chain PFCAs and perfluoroalkyl phosphonic acids were not detected. Perfluorooctane sulfonate (PFOS) was the predominant compound (9.57-1444 ng g−1 wet weight (ww)), followed by perfluorononanoate (PFNA, 0.47-109 ng g−1 ww). C6-C8 PFSAs, PFOSi and C7-C13 PFCAs showed statistically significant increasing concentrations between 1974 and 1997, with a peak in 1997 and then decreased or levelled off (except for C12 and C13 PFCAs). FOSA had a different temporal trend with a maximum in 1989 followed by significant decreasing concentrations until 2008. Toxicological implications for grey seals are limited, but the maximal PFOS concentration found in this study was about 40 times lower than the predicted lowest observed effect concentrations (LOEC). The statistically significant decreasing concentrations or levelling off for several PFCs in the relative closed marine ecosystem of the Baltic Sea indicate a rapidly responding to reduced emissions to the marine environment. However, the high concentrations of PFOS and continuing increasing concentrations of the longer chain PFCAs (C12-C14) shows that further work on the reduction of environmental emissions of PFCs are necessary.  相似文献   
973.
The subject of this study was to develop a method of simultaneous determination of PCDDs/PCDFs and HCB in exhaust gases from industrial installations. Sampling to determine PCDDs/PCDFs was conducted using the method described in PN-EN 1948-1: 2006, where the sorption material is polyurethane foam (PUF). In order to simultaneously collect PCDDs/PCDFs and HCB and to avoid sorbent bed breakthrough, it was necessary to apply an additional polyurethane sorption layer. Twenty-seven samples of exhaust gases from various cement plants and 40 samples of exhaust gases from hospital and industrial waste incineration plants collected in 2009/2010 in the entire territory of Poland were examined. The average content of PCDDs/Fs in samples from cement plants amounted to 0.076 ng I-TEQ N m(-3) (range of 0.002-0.62 ng I-TEQ N m(-3)), while the average content of HCB amounted to 10 ng N m(-3) (range of 0.98-60.5 ng N m(-3)). In the case of samples collected from waste incineration plants, the average concentration of PCDDs/Fs was 0.39 ng I-TEQN m(-3) (range of 0.002-5.68 ng I-TEQ N m(-3)). In the case of HCB, the average concentration was 238 ng N m(-3) (range of 3.21-2500 ng N m(-3)). Also, the interdependence of the concentration of PCDDs/PCDFs and HCB was determined in the analysed samples, with the ranges of low and high content of PCDDs/PCDFs being examined separately. In all cases, the determined values of the r correlation coefficient were within the range of 0.7-1.0, which indicates a good correlation between the concentrations of PCDDs/PCDFs and HCB.  相似文献   
974.
Development of stress markers for the invader freshwater zebra mussel (Dreissena polymorpha) is of great interest for both conservation and biomonitoring purposes. Gene expression profiles of several putative or already established gene expression stress markers (Metallothionein, Superoxide dismutase, Catalase, Glutathione S transferase, Glutathione peroxidase, Cytochrome c oxidase, the multixenobiotic resistance P-gp1, and heat shock proteins HSP70 and HSP90) were analyzed by quantitative Real-Time PCR in adults and pediveliger larvae after exposure to metals (Hg, Cu, Cd). A defined pattern of coordinated responses to metal exposure and, presumably, to oxidative stress was observed in gills and digestive gland from adults. A similar, albeit partial response was observed in larvae, indicating an early development of stress-related gene responses in zebra mussel. The tools developed in this study may be useful both for future control strategies and for the use of zebra mussel as sentinel species in water courses with stable populations.  相似文献   
975.
Environmental Science and Pollution Research - Escherichia coli bacteria are an essential indicator in evaluations of environmental pollution, which is why they must be correctly identified. This...  相似文献   
976.
Environmental Science and Pollution Research - The studies presented in this work show that solid tannery waste-like shavings can be used as high-protein materials for fertilizer production...  相似文献   
977.
Environmental Science and Pollution Research - In this study, we report the potential of 2D/2D TiO2-GO-ZnFe2O4 photocatalyst obtained using the fluorine-free lyophilization technique for the...  相似文献   
978.
近年来,在全球范围内的环境和人体血液中检测到全氟代化合物(PFCs)增长的趋势,引起了研究者和有关当局的关注.PFCs同时具有亲水性和疏水性,经常用于地毯、纤维、皮革的处理、纸张和食品包装物等,也是塑料生产、灭火剂、抛光剂和杀虫剂的功能化学品.  相似文献   
979.
Regional Environmental Change - The calculation of robust estimates of future greenhouse gas emissions due to agriculture is essential to support the framing of the Brazilian climate change...  相似文献   
980.
Lanthanum-modified TiO2 photocatalysts (0.2–1.5 wt% La) were investigated in the methanol decomposition in an aqueous solution. The photocatalysts were prepared by the common sol-gel method followed by calcination. The structural (X-ray diffraction, Raman, X-ray photoelectron spectroscopy), textural (N2 physisorption), and optical properties (diffuse reflectance spectroscopy, photoelectrochemical measurements) of all synthetized nanomaterials were correlated with photocatalytic activity. Both pure TiO2 and La-doped TiO2 photocatalysts proved higher yields of hydrogen in comparison to photolysis. The photocatalyst with optimal amount of lanthanum (0.2 wt% La) showed almost two times higher amount of hydrogen produced at the same time as in the presence of pure TiO2. The photocatalytic activity increased with both increasing photocurrent response and decreasing amount of lattice and surface O species. It has been shown that both direct and indirect mechanisms of methanol photocatalytic oxidation participate in the production of hydrogen. Both direct and indirect mechanisms take part in the formation of hydrogen.  相似文献   
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