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371.
Improved wood-burning stoves offer a possible solution that can simultaneously impact both problems of deforestation and problems of respiratory health in developing countries. We carried out a field experiment in which new fuel-efficient woodstoves were allocated in a Guatemalan village via the use of a lottery. A 2008 baseline survey was carried out on 2,148 individuals in 351 households, and then a follow-up survey was carried out in 2009, 4 months after households received the stoves. We found that households with the new stoves reduced wood consumption by an average of 59.1%. We also found indications of reductions in indoor air related health problems, where point estimates indicate a significant reduction in reported respiratory symptoms by 48.6% among women and 63.3% among children.  相似文献   
372.
The natural resource management literature documents many reasons for pursuing collaborative processes, offering useful insights on how to manage conflict and facilitate productive deliberation in complex multistakeholder collaborative efforts. Moral foundations theory and self-affirmation theory can further help collaborative efforts mitigate conflicts caused by identity threats and the identity-protective reasoning these threats provoke. Moral foundations theory suggests an approach to increase collaboration by minimizing triggering language and helping people appreciate opposing viewpoints. Self-affirmation theory suggests a practical intervention that could be used to increase collaboration by desensitizing people to identity threats and reducing defensiveness. Taken together, these theories can contribute substantially to the understanding and practice of collaboration and conflict management for conservation.  相似文献   
373.
Impact on IndustryPreventing speed-related crashes could reduce costs and improve efficiency in the transportation industry.ObjectiveThis research examined the psychosocial and personality predictors of observed speeding among young drivers.MethodSurvey and driving data were collected from 42 newly-licensed teenage drivers during the first 18 months of licensure. Speeding (i.e., driving 10 mph over the speed limit; about 16 km/h) was assessed by comparing speed data collected with recording systems installed in participants' vehicles with posted speed limits.ResultsSpeeding was correlated with elevated g-force event rates (r = 0.335, pb0.05), increased over time, and predicted by day vs. night trips, higher sensation seeking, substance use, tolerance of deviance, susceptibility to peer pressure, and number of risky friends. Perceived risk was a significant mediator of the association between speeding and risky friends.ConclusionThe findings support the contention that social norms may influence teenage speeding behavior and this relationship may operate through perceived risk.  相似文献   
374.
This paper expands on a simple concept shared with us over three decades ago by Trevor Kletz: what you don’t have can’t leak. Despite many efforts at eliminating hazards through inherently safer process methodologies, as encouraged by Kletz and others, the reality is that the use of hazardous materials and processes is still quite common. Therefore, we consider those processes that still handle hazardous materials – the cases where what you do not manage will leak and may cause a fire, explosion or toxic release. Our intended audience is quite broad. As Kletz has noted over the years, it is not just the people running a process who are responsible for its safety, but also those who make decisions on its design, operation, maintenance, staffing, etc. We hope that this paper contributes to an understanding of why we continue to have hazardous materials leak, potentially leading to accidents that cause fatalities, serious injuries, property damage, and environmental harm.We expand on the fundamental equation for risk, a function of both the frequency and the consequence of a possible event, by considering the effects of poor operational discipline on risk, and ultimately, on the possible leak or release of the hazardous material. Continued safe operation involving hazardous materials depends on and is sustained by the operational discipline of everyone involved in the design of processes and their continuing operation and maintenance. What we do not manage will leak and therein lays the fundamental challenge that Kletz continues to emphasize today.  相似文献   
375.
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   
376.
Converging flows at stream confluences often produce highly turbulent conditions. The shear layer/mixing interface that develops within the confluence hydrodynamic zone (CHZ) is characterized by complex patterns of three-dimensional flow that vary both spatially and temporally. Previous research has examined in detail characteristics of mean flow and turbulence along mixing interfaces at small stream confluences and laboratory junctions; however few, if any, studies have examined these characteristics within mixing interfaces at large river confluences. This study investigates the structure of mean velocity profiles as well as spatial and temporal variations in velocity, backscatter intensity, and temperature within the mixing interfaces of two large river confluences. Velocity, temperature, and backscatter intensity data were obtained at stationary locations within the mixing interfaces and at several cross sections within the CHZ using acoustic Doppler current profilers. Results show that mean flow within the mixing interfaces accelerates over distance from the junction apex. Turbulent kinetic energy initially increases rapidly over distance, but the rate of increase diminishes downstream. Hilbert–Huang transform analysis of time series data at the stationary locations shows that multiple dominant modes of fluctuations exist within the original signals of velocity, backscatter intensity, and temperature. Frequencies of the largest dominant modes correspond well with predicted frequencies for shallow wake flows, suggesting that mixing-interface dynamics include wake vortex shedding—a finding consistent with spatial patterns of depth-averaged velocities at measured cross sections. Spatial patterns of temperature and backscatter intensity show that the converging flows at both confluences do not mix substantially, indicating that turbulent structures within the mixing interfaces are relatively ineffective at producing mixing of the flows in the CHZ.  相似文献   
377.
Farmers in a southwestern Ontario watershed were surveyed to determine factors influencing their attitudes towards adoption of soil conservation practices. The majority of farmers in the watershed were internally motivated which indicates they believe that their own actions determine their successes and failures. Most respondents were also environmentally oriented. However, although many farmers in the study area have adopted crop rotations and cross-slope tillage, the adoption rate of conservation tillage is low. The survey suggests that the low adoption rate may be more a function of perceived economic risk associated with the tillage practice than lack of farmer motivation.  相似文献   
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