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41.
Ground-living spiders were studied using modified pitfall traps during several years in four characteristic habitats in Giant Mountains (Krkono?e Mts.), the High Sudetes, Czech Republic: alpine tundra, subalpine mire, tall-herb stand at the bottom of a glacial corrie, and decaying mountain spruce forest. Ecological and zoogeographical aspects of spider communities were analysed. The spider communities of alpine tundra, subalpine mire, and glacial corrie exhibited long-term stability, whereas the community of decaying mountain forest changed during observations. Small linyphiid spiders, dominating in mature forest, were gradually replaced by larger Iycosid and gnaphosid species. Zoogeographic characterization of mountain habitats was made based on species exhibiting disjunctive area. In contrast to plants, for spiders of boreal origin alpine tundra is the most important habitat for survival, followed by screes, mires, spruce forests, and corries.  相似文献   
42.
The results of an inter-laboratory comparison exercise to determine cytostatic anticancer drug residues in surface water, hospital wastewater and wastewater treatment plant effluent are reported. To obtain a critical number of participants, an invitation was sent out to potential laboratories identified to have the necessary knowledge and instrumentation. Nine laboratories worldwide confirmed their participation in the exercise. The compounds selected (based on the extent of use and laboratories capabilities) included cyclophosphamide, ifosfamide, 5-fluorouracil, gemcitabine, etoposide, methotrexate and cisplatinum. Samples of spiked waste (hospital and wastewater treatment plant effluent) and surface water, and additional non-spiked hospital wastewater, were prepared by the organising laboratory (Jo?ef Stefan Institute) and sent out to each participant partner for analysis. All analytical methods included solid phase extraction (SPE) and the use of surrogate/internal standards for quantification. Chemical analysis was performed using either liquid or gas chromatography mass (MS) or tandem mass (MS/MS) spectrometry. Cisplatinum was determined using inductively coupled plasma mass spectrometry (ICP-MS). A required minimum contribution of five laboratories meant that only cyclophosphamide, ifosfamide, methotrexate and etoposide could be included in the statistical evaluation. z-score and Q test revealed 3 and 4 outliers using classical and robust approach, respectively. The smallest absolute differences between the spiked values and the measured values were observed in the surface water matrix. The highest within-laboratory repeatability was observed for methotrexate in all three matrices (CV?≤?12 %). Overall, inter-laboratory reproducibility was poor for all compounds and matrices (CV 27–143 %) with the only exception being methotrexate measured in the spiked hospital wastewater (CV?=?8 %). Random and total errors were identified by means of Youden plots.  相似文献   
43.
Foods and feeds were analyzed during the period of 2007–2014 employing validated and accredited methods based on gas chromatography–high-resolution mass spectrometry. Sampling has been carried out in-line with national monitoring programs as well as during import controls into Lithuania. Food samples such as eggs, milk, beef, pork, poultry, fats of plant and animal origin, fish, cod liver, and feed samples such as premixes, feeds of plant origin, compound feed, mineral feed, vegetable oil, and fish meals were analyzed. Most of the samples exhibited concentrations below maximum limits, except cod liver. Health impacts were assessed in respect to human daily intakes. Data between groups are compared.  相似文献   
44.
The fungicide tolylfluanid (N - dichlorofluoromethylthio-N′, N - dimethyl - N - p - tolylsulfamide), was investigated by cytokinesis-block micronucleus assay. Tolylfluanid at the lowest concentration (1 × 10? 6mol L? 1)did not influence significantly the frequency of micronuclei in sheep lymphocyte cultures in comparison with control (32.33 ± 3.51/1000 binucleated cells versus 30.33 ± 2.82/1000 binucleated cells in dimethylsulfoxide (DMSO) control, P = 0.44). Higher tolylfluanid concentrations (1 × 10? 4 and, 1 × 10? 5 mol L? 1) resulted in a significant dose-dependent increase in the number of micronuclei in comparison with control (74.00 ± 13.00/1000 binucleated cells and 52.67 ± 10.12/1000 binucleated cells versus 30.33 ± 2. 82/1000 binucleated cells in DMSO control, P = 0.005 and 0.02, respectively, ANOVA followed by Tukey test P < 0.05). Many of the treated cells also possessed multiple micronuclei. Tolylfluanid did not affect the nuclear division index at all treatment concentrations. Our in vitro results thus demonstrate that tolylfluanid had a significant genotoxic effect at only the highest concentration tested.  相似文献   
45.
Twenty microfungal isolates were collected from diseased fruiting bodies of Agaricus bisporus sampled from Serbian mushroom farms during 2003–2007. Based on morphological characteristics and pathogenicity tests, the isolates were identified as Cladobotryum dendroides. The isolates of C. dendroides and A. bisporusF56 and U3 were tested for sensitivity to several selected fungicides in vitro. C. dendroides isolates were found to be more sensitive to prochloraz manganese and flusilazole + carbendazim than to the other fungicides tested (EC50 values were 0.09 and 0.11 mg L? 1, respectively) and weakly resistant to thiophanate-methyl (EC50 values ranged between 6.53 and 12.09 mg L? 1). Selectivity indexes of the tested fungicides on both C. dendroidesand A. bisporusindicated that thiophanate-methyl, cyproconazole + carbendazim and flusilazole + carbendazim had much less selective fungitoxicity than benomyl, carbendazim and prochloraz manganese.  相似文献   
46.
The specific activities of natural radionuclides ((40)K, (226)Ra and (232)Th) and Chernobyl-derived (137)Cs were measured in soil profiles representing typical soil types of Belgrade (Serbia): chernozems, fluvisols, humic gleysols, eutric cambisols, vertisols and gleyic fluvisols. The influence of soil properties and content of stable elements on radionuclide distribution down the soil profiles (at 5 cm intervals up to 50 cm depth) was analysed. Correlation analysis identified associations of (40)K, (226)Ra and (137)Cs with fine-grained soil fractions. Significant positive correlations were found between (137)Cs specific activity and both organic matter content and cation exchange capacity. Saturated hydraulic conductivity and specific electrical conductivity were also positively correlated with the specific activity of (137)Cs. The strong positive correlations between (226)Ra and (232)Th specific activities and Fe and Mn indicate an association with oxides of these elements in soil. The correlations observed between (40)K and Cr, Ni, Pb and Zn and also between (137)Cs and Cd, Cr, Pb and Zn could be attributed to their common affinity for clay minerals. These results provide insight into the main factors that affect radionuclide migration in the soil, which contributes to knowledge about radionuclide behaviour in the environment and factors governing their mobility within terrestrial ecosystems.  相似文献   
47.
Spatial distribution of 238U and 226Ra activities in sediment columns along the Krka River and estuary, were studied using gamma spectrometry. Markedly different 238U and 226Ra activities between riverine, estuarine and marine sediments were observed. Distribution of these radionuclides, as well as their anthropogenic and natural origin, was evaluated by activity measurements, taking into account sedimentation rates estimated by 137Cs distribution in sediment columns.  相似文献   
48.
Recirculation of leachate on a covered landfill site planted with willows or other highly evapotranspirative woody plants is an inexpensive option for leachate management. In our study, a closed landfill leachate recirculation system was established on a rehabilitated municipal solid waste landfill site with planted landfill cover. The main objective of the study was to evaluate the sustainability of the system with regard to high hydraulic loads of the landfill leachate on the landfill cover and high concentrations of saline ions, especially potassium (K+), sodium (Na+) and chloride (Cl?), in leachate.The results of intensive monitoring, implemented during May 2004 and September 2007, including leachate, soil and plant samples, showed a high sustainability of the system regarding saline ions with the precipitation regime of the studied region. Saline ion concentrations in leachates varied between 132 and 2592 mg Cl? L?1, 69 and 1310 mg Na+ L?1 and between 66 and 2156 mg K+ L?1, with mean values of 1010, 632 and 686 mg L?1, respectively. Soil salinity, measured as soil electrical conductivity (EC), remained between 0.17 and 0.38 mS cm?1 at a depth between 0 and 90 cm. An average annual precipitation of 1000 mm provided sufficient leaching of saline ions, loaded by irrigation with landfill leachate, from the soil of the landfill cover and thus prevented possible salinity shocks to the planted willows.  相似文献   
49.
Influence of the economic criterion, called Profit, on the ranking of copper concentrates is investigated. Values of the criterion, which correspond to alternatives, are derived as earning values obtained by the exploitation of individual concentrates. Various scenarios with respect to the weight w 14, corresponding to the additional economical criterion, are defined and solved. A discrete set of results is generated, applying DECISION LAB software implementation of the PROMETHEE-GAIA methodology. Interpolating these results, we derived continuous interpolation functions which compute necessary quantities of concentrates for each real value of w 14 within the interval [0, 100].  相似文献   
50.
The relationship between whole effluent toxicity (WET) and chemical-based effluent quality assessment across a range of effluent types was examined for the first time in Serbia. WET was determined by Daphnia magna acute tests, while chemical-based toxicity was taken as theoretical for concentrations of priority chemicals and effluent quality assessment based on the valid Serbian regulations. A poor correlation was found between WET and chemical-based effluent quality assessment: positive toxicity tests were found, in general, in cases where samples satisfied the requirements of mandatory effluent monitoring. Statistically insignificant correlation between the predicted and observed toxicity indicated that the presence of priority substances accounted to the overall toxicity only to a certain degree, most probably due to a rather short list of priority pollutants regularly analysed in effluents. Current monitoring requirements neglect hazards that derive from potentially present toxicants and unpredictable toxicity of complex mixtures, which led to poor correlation between the WET and chemical-based results in this study.  相似文献   
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