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161.
Changes in material use, energy use and emissions profiles of industry are the result of complex interrelationships among a multitude of technological and economic drivers. To better understand and guide such changes requires that attention is paid to the time-varying consequences that technology and economic influences have on an industry's choice of inputs and its associated (desired and undesired) outputs. This paper lays out an approach to improving our understanding of the dynamics of large industrial systems. The approach combines engineering and econometric analysis with a detailed representation of an industry's capital stock structure. A transparent dynamic computer modeling approach is chosen to integrate information from these analyses in ways that foster participation of stakeholders from industry and government agencies in all stages of the modeling process-from problem definition and determination of system boundaries to generation of scenarios and interpretation of results. Three case studies of industrial energy use in the USA are presented-one each for the iron and steel, pulp and paper, and ethylene industry. Dynamic models of these industries are described and then used to investigate alternative carbon emissions and investment-led policies. A comparison of results clearly points towards two key issues: the need for industry specific policy approaches in order to effectively influence industrial energy use, fuel mix and carbon emissions, and the need for longer time horizons than have typically been chosen for the analysis of industrial responses to climate change policies.  相似文献   
162.
Summary This study is aimed to investigate dependence of nerve pulse conduction velocity on low-level microwave exposure. The changes in fiber membrane permeability or myelin sheath, caused by microwave, should affect nerve pulse conduction velocity. Experimental investigation was carried out for nerve pulse conduction velocity with and without applied microwave field and different orientations of its polarization to the nerve fiber. Microwave radiation of 450 MHz was applied polarized perpendicular or parallel to the nerve fiber. The measured field power density at the skin was 0.87 mW/cm2. Special program was developed for calculation of the nerve pulse conduction velocity in LabView environment. The right nervus medianus motor nerve fibers of 35 young subjects were under the study. The experimental protocol included ten measurements in every cycle of five different exposure conditions. No changes in average values of the conduction velocities discovered in different exposure conditions. Theoretical calculations based on Hodgkin-Huxley model confirm only a weak possible effect. The results showed that low-level microwave radiation did not cause statistically significant change in nerve pulse conduction velocity in human motor nerve fiber.  相似文献   
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164.
ABSTRACT: The Sand and Gravel Aquifer is the sole source of potable water in Escambia County, Florida. In order to better understand the hydraulics of the aquifer, a numerical computer model of the aquifer was developed. The model applied a finite element technique which allowed for density-dependent transport and flow in three dimensions. The modeling technique was integrated with GIS to develop a system for optimal management of the resource. The GIS was the primary tool in the development of the model grid, as well as being the integral component in the modeling procedure. Multiple model grids were developed for simulating regional flow and local flow/transport phenomena. The model grids were generated by the GIS where nodal and element sequencing were recorded. The grid topology was stored in the GIS with the element numbers, node numbers, and the related hydrogeologic attributes. The Triangulated Irregular Network (TIN) module was used for transferring interpolated value between GIS coverages. TIN allowed a fit of the model grid to the physical dimensions of the aquifer and for interpolating boundary values for telescopically refined grids. Calculations between TIN surfaces provided the residuals of the dependent variable from observed TIN surfaces. Model calibration was conducted within the GIS environment through a combination of visual and relational querying. The GIS provided an integrated environment which facilitated model analyses and data storage and retrieval.  相似文献   
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166.
On November 5-7, 2002, the Symposium on Graduated Driver Licensing in Chatham, MA, brought together 75 researchers and practitioners from the United States, Canada, Australia, and New Zealand to document the current science of graduated driver licensing (GDL) and to outline research needs. Participants reviewed 12 background papers and discussed the papers in depth. The symposium's background papers are published in this issue of the Journal of Safety Research.This paper summarizes and provides a quick reference to information from the symposium papers and participant discussions. It cites the 12 symposium papers, which in turn provide more information and cite original sources. Issues and recommendations not followed by a citation were raised in the symposium discussions.This paper is divided into seven sections. The first six sections summarize information from the symposium papers and discussions. The sections are: (1) The need for graduated driver licensing; (2) Effectiveness of GDL as implemented; (3) The learner's permit phase; (4) The provisional license phase; (5) The roles of teens, parents, and public agencies; and (6) Enacting and implementing GDL. In each of these six sections, research needs are classified as either high priority (important for designing and implementing effective GDL programs) or lower priority (useful but not critical for GDL at this time).The final section summarizes the discussion of research issues and priorities from the symposium's closing session. This section has three topics: general research, issues involving parents, and issues involving graduated licensing legislation and implementation. It presents participants' collective views on both broad priorities and specific issues.In providing a concise summary of presentations and discussions from the symposium, this paper necessarily omits some information and points of discussion. The views and judgments expressed are the authors' best attempt to capture the symposium's consensus, but they do not necessarily represent the views of the authors, their organizations, or any other individual symposium participant. In particular, they are not necessarily endorsed by the symposium's sponsors: General Motors, the National Highway Traffic Safety Administration, the National Safety Council, and Nationwide.  相似文献   
167.
The combined effect of ultraviolet (UV)-ozonation (O3) of aqueous 14C-TNT solutions followed by direct addition of the solutions to aerobic soils was examined as a method of disposal. The effect of TNT concentration was studied on both UV-O3 and soil metabolism. The amount of TNT degraded by either process decreased as the concentration increased. UV-O3 of a 1 ppm solution of TNT using a laboratory 450 W lamp for 10, 20, and 30 minutes resulted in substantial fragmentation of the ring and an increase in polarity of the resultant products. Soil metabolism, as measured by metabolic CO2 evolution, increased as the time of prior UV-O3 increased. A large amount of the 14C associated with 14C-TNT recovered from soil was in the non-extractable fraction. When a , adapted to metabolize -nitrophenol or picric acid as a sole source of carbon and nitrogen, was substituted for the soil phase, about 25% of the added 14C appeared as 14CO2. 1,3,5-Trinitrobenzene, 2,4,6-trinitrobenzaldehyde, 3,5-dinitrophenol, 3, 5-dinitrocatechol, 3,5-dinitrohydroquinone, and oxalic acid were identified as products of UV-O3. Rapid destruction of TNT took place in a large 66 lamp unit, and the resultant distribution of 14C was similar to the results from the laboratory studies.  相似文献   
168.
Two regioselective synthetic routes to 1,2,3,6,7,8-hexachlorodibenzo-p-dioxin have been developed. Each consists of dinitration of a tetrachlorodibenzo-p-dioxin followed by reduction and a Sandmeyer reaction.  相似文献   
169.
National parks have complex relationships with local communities that impact both conservation success and community well-being. Integrated conservation and development projects have been a key approach to managing these relationships, although their effectiveness has been increasingly questioned. Park-people relationships of the Armando Bermudez National Park in the Dominican Republic were studied, focusing on forests, aquatic resources, community well-being and development, and ecotourism. The park, established in 1956, is well respected by the community, based on its long history and its role in protecting water resources that are critical to the community. However, management of riparian vegetation and local fisheries present challenges in terms of finding a balance between conservation and development. Hiking and trekking opportunities attract both national and international tourists to the park, and community members benefit from employment as tour guides and providing mule rentals. At the same time, tourism activities also present continuing challenges related to: (1) the distribution of tourism benefits between local people and outsiders, and within the local community, (2) maintaining the local economic benefits of tourism while protecting park resources, and (3) developing park- or conservation-related economic opportunities to complement tourism. The results highlight the need to develop site-specific strategies to manage park-people relationships through interdisciplinary analysis.  相似文献   
170.
Objective: We examined the prevalence of and characteristics associated with drink-driving in China. We compared this study's drink-driving findings with those from the United States to explore how effective traffic safety interventions from Western cultures might be adapted for use in China.

Methods: Data from the 2010 China Chronic Disease and Risk Factor Survey were analyzed to describe the prevalence and characteristics associated with drink-driving in China.

Results: Overall, 1.5% of Chinese adults reported drink-driving in the past 30 days—3% of males and 0.1% of females. However, among males who had driven a vehicle in the past 30 days and consumed at least one alcoholic beverage in the past 30 days, 19% reported drink-driving during the 30-day period. Excessive drinking, binge drinking, nonuse of seat belts, and having been injured in a road traffic crash in the past year were most strongly associated with drink-driving among males.

Conclusions: Drink-driving is prevalent among male drivers in China. Although large differences exist between China and the United States in the proportion of adults who drive, the proportion who consume alcohol, and some of the personal characteristics of those who drink and drive, similarities between the 2 countries are present in patterns of risk behaviors among drink-driving. To reduce injuries and deaths from drink-driving, effective interventions from Western cultures need to be tailored for adoption in China.  相似文献   

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