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51.
Oxidative stress and antioxidant responses of crucian carp, upon chronic exposure to endosulfan, were evaluated in vivo. The lethal concentration (LC50–96?h) was 70 μg L?1; on its basis, the fish were exposed to endosulfan at 20, 35, and 50 μg L?1 and autopsy was done on days 1, 2, 3, 4, 7, 14, 21, 28, and 35. Lipid peroxidation was induced in a concentration-dependent manner, being highest at 50 μg L?1 (3/4 LC50–96 h, sub-lethal concentration-I, SL-I) on day 4 (720% versus control), followed in its extent (490%) at 30 μg L?1 (1/2 LC50–96 h, sub-lethal concentration-II, SL-II) on day 7 and lowest (260%) at 10 μg L?1 (1/4 LC50–96 h, sub-lethal concentration-III, SL-III) on day 14. Glutathione showed a concentration- and time-dependent elevation in the initial phase, with highest level on day 4 (180%) at SL-I, but showed significant reduction in all test concentrations from day 21 of post-exposure. Superoxide dismutase was decreased significantly throughout the study, with highest reduction (63%) on day 4 at SL-I; catalase increased in all test concentrations up to day 14 but showed a significant decrease from the day 28 of post-exposure. The potential role of these parameters as indicators of pesticide pollution in aquatic systems is discussed.  相似文献   
52.
We propose a space-time stick-breaking process for the disease cluster estimation. The dependencies for spatial and temporal effects are introduced by using space-time covariate dependent kernel stick-breaking processes. We compared this model with the space-time standard random effect model by checking each model’s ability in terms of cluster detection of various shapes and sizes. This comparison was made for simulated data where the true risks were known. For the simulated data, we have observed that space-time stick-breaking process performs better in detecting medium- and high-risk clusters. For the real data, county specific low birth weight incidences for the state of South Carolina for the years 1997–2007, we have illustrated how the proposed model can be used to find grouping of counties of higher incidence rate.  相似文献   
53.
Biofouling is a stubborn problem in cooling systems where using raw water from lakes, rivers, and sea. The effect of ultrasound and its sequential application with sodium hypochlorite (chlorination) upon marine bivalve Mytilus edulis (blue mussel), a massive fouling organism, has been studied and discussed here. The results obtained from the work carried out have shown that 42 kHz ultrasound is better than 28 kHz in accordance with veliger larvae mortality. The 42 kHz ultrasound has enhanced the mortality rate of veliger larvae than only free-residual chlorination up to 99%. On the other side, the 14-mm size mussel was less resistance than 25-mm size mussel to 42 kHz ultrasonication, among the studied two sizes (14 and 25 mm) of the blue mussel. Lethal time (100%) have decreased by 1–12% used for the sequential action of 42 kHz ultrasonic followed by free-residual chlorination compare with only free-residual chlorination treatment. The obtained results are put forward that the application of ultra-sonication before chlorination can reduce the mussel extinct time up to 12%. Obviously, this result will provide a possible use of ultra-sonication with famous chlorination antifouling treatment and eventually can decrease the chlorine exposure time and dose. It could discharge low chlorine by-products that may provide an environment friendly way.  相似文献   
54.
The effects of an arbuscular mycorrhizal fungi (AMF) association on the growth, survival capabilities, nutrients and lead (Pb) uptake of Miscanthus sacchariflorus under different Pb concentrations were studied in the form of pot cultures. The treatments comprised inoculation or non-inoculation of the AMF, Gigaspora margarita, and the addition of three Pb concentrations to the soil (0, 100 and 1000?mg?kg?1). The addition of Pb significantly decreased mycorrhizal colonisation. The inoculation of AMF with Pb increased chlorophyll content, Fv/Fm, total dry mass, indole-3-acetic acid (IAA), total nitrogen, and total phosphorus, whereas H2O2 level, indole-3-acetic acid oxidase (IAAO) activity, and peroxidase (POD) activity were low compared to those in the non-inoculated treatments. Moreover, the application of AMF together with Pb doses induces concentrations of Pb in the plant, where the higher dose of Pb (1000?mg?kg?1) induces a lower content of Pb in the aerial part of the plant but a higher content in the root. G. margarita enhanced the tolerance of M. sacchariflorus against Pb toxicity, and facilitated the accumulation of Pb in the plant roots, whereas translocation to the shoots was inhibited at the highest dose Pb (1000?mg?kg?1). However, in contaminated soil, the Pb removal capability of M. sacchariflorus with AMF was remarkable.  相似文献   
55.
Journal of Polymers and the Environment - The aim of this study is to investigate the effect of fiber length and loading on physico-mechanical and flammability properties of Cyrtostachys renda (CR)...  相似文献   
56.
Three strains of the chain-forming diatom Skeletonema marinoi, differing in their production of polyunsaturated aldehydes (PUA) and nutritional food components, were used in experiments on feeding, egg production, hatching success, pellet production, and behavior of three common planktonic copepods: Acartia tonsa, Pseudocalanus elongatus, and Temora longicornis. The three different diatom strains (9B, 1G, and 7J) induced widely different effects on Acartia tonsa physiology, and the 9B strain induced different effects for the three copepods. In contrast, different strains induced no or small alterations in the distribution, swimming behavior, and turning frequency of the copepods. 22:6(n-3) fatty acid (DHA) and sterol content of the diet typically showed a positive effect on either egg production (A. tonsa) or hatching success (P. elongatus), while other measured compounds (PUA, other long-chain polyunsaturated fatty acids) of the algae had no obvious effects. Our results demonstrate that differences between strains of a given diatom species can generate effects on copepod physiology, which are as large as those induced by different algae species or groups. This emphasizes the need to identify the specific characteristics of local diatoms together with the interacting effects of different mineral, biochemical, and toxic compounds and their potential implications on different copepod species.  相似文献   
57.
Food and Environmental Virology - The performance of dishwashers in removing live viruses is an important informative value in practical applications. Since foodborne viruses are present in...  相似文献   
58.
Environmental Science and Pollution Research - The objective of this paper was to stress the possible potential toxic element (PTE) accumulation in the surface sediments of the Çavu?lu...  相似文献   
59.
Environmental Science and Pollution Research - Colorectal cancer was inducted in Wister rats using titanium dioxide nanoparticles (TiO2NPs) and dimethylhydrazine (DMH) and treatment using...  相似文献   
60.
Environmental Science and Pollution Research - The n–n-type ZnO–SnO2 nanocomposite was fabricated using malic acid following a simple one-pot co-precipitation method. The fabricated...  相似文献   
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