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431.
ABSTRACT: Many urban and suburban communities in the Midwest are seeking to establish sustainable, morphologically and hydraulically varied, yet dynamically stable fluvial systems that are capable of supporting healthy, biologically diverse aquatic ecosystems — a process known as stream naturalization. This paper describes an integrated research program that seeks to develop a scientific and technological framework to support two stream naturalization projects near Chicago, Illinois. The research program integrates theory and methods in fluvial geomorphology, aquatic ecology, hydraulic engineering and social theory. Both the conceptual and the practical challenges of that integration are discussed. Scientific and technical support emphasize the development of predictive tools to evaluate the performance of possible naturalization designs at scales most appropriate to community based projects. Social analysis focuses on place based evaluations of how communities formulate an environmental vision and then, through decision making, translate this vision into specific stream naturalization strategies. Integration of scientific and technical with social components occurs in the context of community based decision making as the predictive tools are employed by project scientists to help local communities translate their environmental visions into concrete environmental designs. Social analysis of this decision making process reveals how the interplay between the community's vision of what they want the watershed to become, and the scientific perspective on what the watershed can become to achieve the community's environmental goals, leads to the implementation of specific stream naturalization practices.  相似文献   
432.
This paper describes several alternatives to traditional methods of army training on dedicated ranges using live, full-calibre ammunition. These are: training/sub-calibre ammunition; training over private land; live or engagement simulation; virtual reality (VR) simulation; constructive simulation; and mechanical simulation. The advantages and disadvantages of each are examined with respect to military and environmental considerations. Varied examples from the British, US and Swiss armies are used to examine the future role of these alternative approaches in meeting a fast-changing training requirement within multiplying environmental controls and resource constraints. This paper concentrates particularly on the training requirements of artillery systems because these are amongst the most demanding in resource terms. The three cited nations operate similar artillery systems and are subject to similar constraints. The US Army's move towards simulation has been triggered largely by economic and operational factors along with tightening regulatory controls. The Swiss and British forces are highly constrained by space, the British due to population density and the Swiss due to topography. While all the alternatives offer environmental and resource advantages, VR simulation provides the most positive benefits.  相似文献   
433.
434.
Book reviews     
Baker  Ilyas  Kassas  M.  Bandler  Hans  Lisowski  Marylin  Disinger  John F.  Duthie  David  Briggs  K. B. 《The Environmentalist》1992,12(4):291-304
Environment Systems and Decisions -  相似文献   
435.
Acid rain in Asia   总被引:3,自引:0,他引:3  
Acid rain has been an issue of great concern in North America and Europe during the past several decades. However, due to the passage of a number of recent regulations, most notably the Clean Air Act in the United States in 1990, there is an emerging perception that the problem in these Western nations is nearing solution. The situation in the developing world, particularly in Asia, is much bleaker. Given the policies of many Asian nations to achieve levels of development comparable with the industrialized world—which necessitate a significant expansion of energy consumption (most derived from indigenous coal reserves)—the potential for the formation of, and damage from, acid deposition in these developing countries is very high. This article delineates and assesses the emissions patterns, meteorology, physical geology, and biological and cultural resources present in various Asian nations. Based on this analysis and the risk factors to acidification, it is concluded that a number of areas in Asia are currently vulnerable to acid rain. These regions include Japan, North and South Korea, southern China, and the mountainous portions of Southeast Asia and southwestern India. Furthermore, with accelerated development (and its attendant increase in energy use and production of emissions of acid deposition precursors) in many nations of Asia, it is likely that other regions will also be affected by acidification in the near future. Based on the results of this overview, it is clear that acid deposition has significant potential to impact the Asian region. However, empirical evidence is urgently needed to confirm this and to provide early warning of increases in the magnitude and spread of acid deposition and its effects throughout this part of the world.  相似文献   
436.
Packaging waste has become a focus for attention by policy‐makers in a number of countries. This article offers a simple policy measure — a packaging tax or levy — which serves the required aims of policy, namely: reducing waste at source; increasing the rate of recycling; and consistency with the polluter pays principle. The tax is illustrated in the context of beverage containers in the UK and Japan. The merits of the proposal are its simplicity and flexibility. The article suggests that the relevant environmental damages are captured by waste disposal costs and litter. Other life cycle impacts, such as emissions from energy use, could be included but only if there are not more efficient ways of regulating them.  相似文献   
437.
ABSTRACT: Most water-resouree investigations in semiarid basins of the Great Basin in western North America conclude that ground-water recharge from direct precipitation on the valley floor is negligible. However, many of these basins contain large areas covered by unvegetated, active sand dunes that may act as conduits for ground-water recharge. The potential for this previously undocumented recharge was investigated in an area covered by sand dunes in Desert Valley, northwestern Nevada, using a deep percolation model. The model uses daily measurements of precipitation and temperature th determine energy and moisture balances, from which estimates of long-term mean annual recharge are made. For the study area, the model calculated a mean annual recharge rate of as much as 1.3 inches per year, or 17 percent of the long-term mean precipitation. Model simulations also indicate that recharge would be virtually zero if the study area were covered by vegetation rather than dunes.  相似文献   
438.
439.
This study investigated the possible role of self-efficacy in the stress process by examining relations between stressors (role ambiguity, situational constraints, and hours), strains (job dissatisfaction, anxiety, frustration, and turnover intent), and efficacy beliefs (both individual and collective). Individual efficacy was related to only two of the four strains and had no mediating or moderating effects. Collective efficacy, however, was strongly related to both stressors and strains. Collective efficacy also moderated the effect of work hours and mediated the relation between situational constraints and two of the strain measures. It was concluded that the theory of individual self-efficacy (Bandura, 1977) may not adequately explain collective efficacy. Future research on the self-efficacy construct as well as its role in the stress process was suggested.  相似文献   
440.
This study explored whether two principles describe the relationship between the size of a pay increase (a bonus expressed as a percentage of current salary) and the attractiveness of that increase. Based on a sample of sales personnel (N = 639) and consistent with the constant proportion principle of the psychophysical law, pay increase attractiveness was unrelated to current salary level after controlling for the size of the percentage increase. In addition, at any given salary level, the relationship between the size of the increase and its attractiveness was curvilinear. The attractiveness of larger and larger bonus percentages continues to increase, but at a decreasing rate supporting the principle of diminishing returns.  相似文献   
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