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Based on data collected from 205 vertical dyads, we found that subordinate–supervisor similarity in their self‐reported growth‐need strength (GNS) had a positive effect on subordinate‐perceived and supervisor‐perceived global similarity. The findings also suggested that subordinate‐perceived global similarity mediates the link between similarity in GNS and subordinate's trust in and loyalty to supervisor; whereas supervisor‐perceived global similarity mediates the link between similarity in GNS and supervisor‐rated in‐role/extra‐role performances. In addition, we found that subordinate–supervisor similarity in self‐reported GNS and perceived global similarity had independent effects on work outcomes for both subordinates and supervisors. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   
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The linearity of the interspecies relation between the elemental contents in Parmelia sulcata and Lecanora conizaeoides, sampled in a polluted area, was examined by the function y=az+b and yz –1=a+bz –1, with y and z being the elemental content in Parmelia and Lecanora, respectively. For As, Co, V and Zn significant positive a and b values were found, allowing interspecies calibration. For Br, Cd, Cr, Fe, La, Sb, Se and W the a values were zero and the b values were positive, indicating saturation of Parmelia and thus ruling out interspecies calibration. For Cu a part of the data set showed saturation effects in Lecanora. The results showed that the average concentration ratio could not be used for intercalibration purposes, because the concentration ratios were dependent on the concentrations.  相似文献   
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The objectives of the study are to present a critical review of the 238U, 234U, 235U, 226Ra and 210Pb levels in water samples from the EPA studies (U.S. EPA in Abandoned uranium mines and the Navajo Nation: Red Valley chapter screening assessment report. Region 9 Superfund Program, San Francisco, 2004, Abandoned uranium mines and the Navajo Nation: Northern aum region screening assessment report. Region 9 Superfund Program, San Francisco, 2006, Health and environmental impacts of uranium contamination, 5-year plan. Region 9 Superfund Program, San Franciso, 2008) and the dose assessment for the population due to ingestion of water containing 238U and 234U. The water quality data were taken from Sect. “Data analysis” of the published report, titled Abandoned Uranium Mines Project Arizona, New Mexico, Utah–Navajo Lands 1994–2000, Project Atlas. Total uranium concentration was above the maximum concentration level for drinking water (7.410–1 Bq/L) in 19 % of the water samples, while 238U and 234U concentrations were above in 14 and 17 % of the water samples, respectively. 226Ra and 210Pb concentrations in water samples were in the range of 3.7 × 10?1 to 5.55 × 102 Bq/L and 1.11 to 4.33 × 102 Bq/L, respectively. For only two samples, the 226Ra concentrations exceeded the MCL for total Ra for drinking water (0.185 Bq/L). However, the 210Pb/226Ra ratios varied from 0.11 to 47.00, and ratios above 1.00 were observed in 71 % of the samples. Secular equilibrium of the natural uranium series was not observed in the data record for most of the water samples. Moreover, the 235U/totalU mass ratios ranged from 0.06 to 5.9 %, and the natural mass ratio of 235U to totalU (0.72 %) was observed in only 16 % of the water samples, ratios above or below the natural ratio could not be explained based on data reported by U.S. EPA. In addition, statistical evaluations showed no correlations among the distribution of the radionuclide concentrations in the majority of the water samples, indicating more than one source of contamination could contribute to the sampled sources. The effective doses due to ingestion of the minimum uranium concentrations in water samples exceed the average dose considering inhalation and ingestion of regular diet for other populations around the world (1 μSv/year). The maximum doses due to ingestion of 238U or 234U were above the international limit for effective dose for members of the public (1 mSv/year), except for inhabitants of two chapters. The highest effective dose was estimated for inhabitants of Cove, and it was almost 20 times the international limit for members of the public. These results indicate that ingestion of water from some of the sampled sources poses health risks.  相似文献   
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Three sets of zooplankton trawls with multiple nets were deployed in June 1990 within a deep (2000 m) scattering layer overlying the central hydrothermal vent field on the Endeavour segment of Juan de Fuca Ridge in the northeast Pacific. Trawl data were collected concurrently with temperature, salinity, light attenuation and acoustic (150 kHz) backscatter profiles. We describe the composition, size distribution and biomass of zooplankton collected in the net samples, and compare biomass distributions with physical characteristics of the hydrothermal plume. The nine discrete trawl samples (1 mm mesh) contained zooplankton biomass of between 0.3 and 21 mg dry wt m-3 with the highest biomass samples coincident with large and positive (+20 dB) acoustic backscatter anomalies observed above the top of the hydrothermal plume. Lowest biomass samples were coincident with small, negative (-5 dB) backscatter anomalies within the core of the plume. Results suggest that the region within a hundred meters of the top of the plume was a zone of enhanced zooplankton concentration associated with nutrition enrichment related to the plume. In contrast, the plume core was a zone of faunal depletion, presumably linked to adverse plume chemistry. The species composition and size distribution profiles from net samples revealed that the epi-plume assemblage contained several trophic levels of bathypelagic fauna, but did not contain benthic larvae or vent-related benthopelagic fauna.  相似文献   
87.
非洲丰富的矿产资源对于其发展具有非同寻常的潜在贡献.本文罗列了这些财富发挥作用的一些制约因素.提出了保障采矿业对地区、国家和地方的可持续性发展做出贡献的建议.抵触的消除,使这些资源转向民间开发有了可能.  相似文献   
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/ The Council on Environmental Quality's (CEQ's) principal aims in implementing the National Environmental Policy Act (NEPA) are (1) to reduce paperwork, (2) to avoid delay, and most importantly (3) to produce better decisions that protect, restore, and enhance the environment. This paper presents four strategies for improving the NEPA process along with tools that can be used to implement each strategy. The tools include guidelines for project management and problem definition, tips for acquiring existing information and identifying issues of public concern, worksheets on how to identify and analyze potential impacts on resources, ideas for enhancing NEPA documents, and a NEPA process checklist. The tools can be used at various stages of the NEPA process and provide a toolbox of guidelines and techniques to improve implementation of the NEPA process by focusing the pertinent information for decisionmakers and stakeholders. KEY WORDS: National Environmental Policy Act; NEPA; Environmental impact assessment; Ecosystem management  相似文献   
90.
Several surveys have investigated the nature of farming under urban fringe conditions but none, until now, have involved the continuous monitoring of criminal and civil law incidents over a period of time. This paper describes the results of such a survey on urban fringe farms between Tyneside and Sunderland in North‐East England. The analysis outlines the nature of offences which occurred, the type of offender, the time incurred by and cost of the incident to the farmer. The cost of the offences should determine how many resources are devoted to remedying the problem, e.g. in modifying local plans.  相似文献   
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