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81.
Environment, Development and Sustainability - The tourism sectors consume a high amount of electrical power, which in most cases is supplied by the electrical grid and diesel generator. As a...  相似文献   
82.
Environmental Economics and Policy Studies - Economists have long argued over the political economy of tradable emission permits, especially the political pressure of lobby groups on international...  相似文献   
83.
Environmental Science and Pollution Research - In this study, simultaneous removal of an organic matter (diazinon, DIZ) and an inorganic substance (chromium, Cr) was used. Breaking down of organic...  相似文献   
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85.
Micro-habitat characteristics of breeding display Sites (Leks) of Caucasian Black Grouse (Tetrao mlokosiewiczi) were studied in the mountains of Arasbaran Region, East Azerbaijan, from October 2006 to June 2008. We quantified micro-habitat characteristics around active and inactive Caucasian black grouse lek sites and random points in the 3 areas (Biosphere reserve, Kalan protected area (one of core zones of Arasbaran biosphere reserve) and unprotected areas)). Our objective was to compare micro-habitat characteristics among these sites. We also developed a logistic regression model to identify micro-habitat factors have important effect in the active lek sites. In the micro-habitat scale, we measured both biotic factors (canopy cover (%), height (cm) and frequency of vegetations) and abiotic (physical) factors (slope (%), altitude (m), aspect and etc.). Slope and altitude were different significantly between sampling sites (p = 0.05). Mean of slope in the active leks (= 57.9%) and inactive leks (= 52.0%) were higher than random sites (= 40.1%). The mean aspect differed between active leks ( $ \bar X $ = 284°, S.D = 54.1°) and random sites ( $ \bar X $ = 33°, S.D = 76.18°) (Watson’s U2-test, U 0.05, 22, 27 2 = 0.717). Also, variance analysis (ANOVA) revealed that grasses and forbs cover, frequency of deciduous shrubs and forbs, canopy cover and frequency of deciduous woody plants > 12 cm diameter at breast height were different significantly between sampling sites. The best model for discriminating between active lek and random sites included rock-pavement cover (parameter estimate [B] = 0.286, SE = 0.219), canopy cover of grasses (parameter estimate [B] = 0.880, SE = 0.453), distance to the nearest tree (parameter estimate [B] = ?0.047, SE = 0.027).  相似文献   
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87.
Study of trace elements in wet atmospheric precipitation in Tehran,Iran   总被引:1,自引:0,他引:1  
In this study, measurements of the trace metals Zn, Cd, Cr, Ni, Pb, Cu, Fe and Al were performed on 53 wet atmospheric precipitation samples (snow and rainwater) collected at a central site of Tehran. Samples were collected using a bulk sampler equipped with a high-density polyethylene funnel from November to May in 2011 and 2012 on the roof of a building in the city centre. Trace metals in the filtered samples were measured with ICP-MS. Statistical analysis of the results revealed that Al, which is principally a crustal-derived element, was the highest mean measured concentration. The pH ranged from 4.2 to 7.1 with a mean value of 5.1. Crustal enrichment factors (EFc) related to the relative abundance of elements in crustal material was calculated using Al as reference crustal. EFc calculations indicated that samples were not enriched with Fe and Cr but were, fairly to extremely, enriched with Zn, Cd, Ni, Pb and Cu. Factor component analysis with varimax-normalized rotation was conducted to find the probable sources of the measured species. This resulted in two factors with eigenvalues greater than unity. Factor 1 showed an anthropogenic source, mostly industrial combustion and local traffic emissions, for Zn, Cd, Ni, Pb, and Cu while factor 2 showed a crustal contribution for Al, Fe and Cr.  相似文献   
88.
A new complexing agent, 2-((2-((1H-benzo[d]imidazole-2yl)methoxy)phenoxy)methyl)-1H-benzo[d]imidazole (BIMPI), was used in cloud point extraction and applied for selective pre-concentration of trace amounts of cadmium in cigarette samples. Cadmium was complexed with BIMPI in a buffer solution (pH?=?10) using Triton X-114 as surfactant and quantitatively extracted into a small volume of the surfactant-rich phase after centrifugation. Under optimized conditions (pH?=?10.0, 0.8?×?10?4?mol?L?1 BIMPI and 0.08 % (w/v) Triton X-114), calibration graph was linear in the range of 34.0–1,670.0 μg?L?1. The proposed method was applied to the determination of Cd in various cigarette (tobacco) samples which gave satisfactory results.  相似文献   
89.
A novel nanomaterial has been developed for speciation of Cr(III) and Cr(VI) in water and soil samples. In this study, a new type of alumina-coated magnetite nanoparticles (Fe3O4/Al2O3 NPs) modified by the surfactant Triton X-114 has been successfully synthesized and used in magnetic mixed hemimicelles solid-phase extraction procedure. The procedure was based on the reaction of chromium(III) with 1-(2-pyridilazo)-2-naphtol as a ligand, yielding a complex, which was entrapped “in situ” in the surfactant hemimicelles. The concentration of chromium(III) was determined using flame atomic absorption spectrometry. After reduction of Cr(VI) to Cr(III) by ascorbic acid, the system was applied to the total chromium. Cr(VI) was then calculated as the difference between the total Cr and the Cr(III) content. This method can also be used for complicated matrices such as soil samples without any special pretreatment. Under the optimum conditions of parameters, the recoveries of Cr(III) by analyzing the spiked water and soil samples were between 98.6 and 100.8 % and between 96.5 and 100.7 %, respectively. Detection limits of Cr(III) were between 1.4 and 3.6 ng?mL?1 for water samples and 5.6 ng?mg?1 for soil samples.  相似文献   
90.
This paper presents an efficient methodology for developing pollutant discharge permit trading in river systems considering the conflict of interests of involving decision-makers and the stakeholders. In this methodology, a trade-off curve between objectives is developed using a powerful and recently developed multi-objective genetic algorithm technique known as the Nondominated Sorting Genetic Algorithm-II (NSGA-II). The best non-dominated solution on the trade-off curve is defined using the Young conflict resolution theory, which considers the utility functions of decision makers and stakeholders of the system. These utility functions are related to the total treatment cost and a fuzzy risk of violating the water quality standards. The fuzzy risk is evaluated using the Monte Carlo analysis. Finally, an optimization model provides the trading discharge permit policies. The practical utility of the proposed methodology in decision-making is illustrated through a realistic example of the Zarjub River in the northern part of Iran.  相似文献   
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