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991.
Twenty-five years of HAZOPs 总被引:7,自引:0,他引:7
The HAZOP or hazard and operability study was developed by ICI over 25 years ago and is in wide use today throughout the world. The technique is intended to review, in a formalized manner, the design of a system such as a chemical process production plant to detect potential problems in the operation of the system. The system has been extended for use on all types of production, storage and distribution units. Experience in the use of hazard studies has lead to the development of a phased approach with three distinct design phases. 相似文献
992.
The National Forest Management Act (1976) specifies that multiresource inventories be conducted to provide baseline data for
development and, later, monitoring of national forest management plans. This mandate entails the most ambitious and complex
resource planning effort ever attempted. In this paper we evaluate the structure and use of current inventory-monitoring programs
and recommend a framework for gathering data to improve national forest planning. Current national guidelines are general
and provide only basic directions to forest-level planners. Forest inventories have traditionally concentrated on timber.
Although these inventories are often well designed, the questions we are now asking about forest resources have outgrown these
methods. Forest management is impeded by general confusion over definitions of resources and the interactions among them.
We outline a simple classification scheme that centers on identification of basic ecosystem elements that can be readily measured.
Furthermore, spatial and temporal scales must be considered in the design of inventory-monitoring programs. The concept of
ecological indicators is reviewed, and caution is advised in their use. Inventory-monitoring programs should be goal-directed
and based on as rigorous a statistical design as possible. We also review fundamental issues of variable selection, validation,
and sampling bias. We conclude by developing a flexible inventory-monitoring program that is designed to provide information
on individual characteristics of the environment, rather than being based on fixed definitions of resources. 相似文献
993.
Large-scale constructed wetlands for nutrient removal from stormwater runoff: An everglades restoration project 总被引:14,自引:0,他引:14
Mariano Guardo Larry Fink Thomas D. Fontaine Susan Newman Michael Chimney Ronald Bearzotti Gary Goforth 《Environmental management》1995,19(6):879-889
The South Florida Water Management District (SFWMD) constructed a wetland south of Lake Okeechobee to begin the process of
removing nutrients (especially phosphorus) from agricultural stormwater runoff entering the Everglades. The project, called
the Everglades Nutrient Removal (ENR) project, is a prototype for larger, similarly constructed wetlands that the SFWMD will
build as part of the Everglades restoration program. This innovative project is believed to be one of the largest agricultural
stormwater cleanup projects in the United States, if not in the world. This publication describes the ENR project's design,
construction, and proposed operation, as well as the proposed research program to be implemented over the next few years. 相似文献
994.
The Clean Air Act Amendments of 1977 designated national parks and wilderness areas larger than 1894 ha to be class I areas
for air quality management, setting more restrictive criteria than the National Ambient Air Quality Standards. Class I areas
are afforded the greatest degree of air quality protection under the Clear Air Act of 1970. In recent years, several studies
have documented air pollution effects in the Great Smoky Mountains National Park (GSMNP), the second-largest class I area
in the eastern United States. Air pollution problems of greatest concern in the GSMNP are effects of acid deposition, visibility
impairment, and tropospheric ozone. Several recent events have increased concerns about air quality management in the class
I area of the GSMNP. A forum, sponsored by the Southern Appalachian Man and the Biosphere Cooperative (SAMAB), was held in
March 1992, which involved representative. parties-at-interest and began to address strategies for better management of air
resources in the Southern Appalachians. This paper summarizes those discussions and recommendations and reports actions occurring
as a result of the forum. Another objective of this paper is to present a conceptual framework for more effective management
of the class I area of the GSMNP. 相似文献
995.
Interest in the concept—and implementation—of environmental excellence is at an all-time high. A wealth of examples from individual companies, trade associations, states, industry coalitions, and the federal government illustrate the growing acceptance by a wide range of stakeholders of a management systems approach to environmental issues. Perhaps nowhere is this more clear than in the collection of public comments submitted to EPA in response to its January 15, 1993, Federal Register notice, which proposed the creation of an Environmental Leadership Program (ELP). The authors, both of whom worked on the ELP, review these public comments and offer a set of “do's and don'ts” for organizations interested in establishing an environmental excellence program. In addition, the authors outline the Green Track proposal, a plan to structure an alternate regulatory pathway based on environmental excellence. 相似文献
996.
Richard S. Krannich Sean P. Keenan Michael S. Walker Donald L. Hardesty 《Journal of the American Water Resources Association》1995,31(5):851-865
ABSTRACT: Survey data collected in the San Joaquin Valley of southern California and the Grand Valley of western Colorado reveal that residents of both areas believe that a severe sustained drought is likely to occur within the next 20–25 years and that their communities would be seriously impacted by such an event. Although a severe sustained drought affecting the Colorado River Basin would cause major economic and social disruptions in these and other communities, residents express little support for water management alternatives that would require significant shifts in economic development activities or in water use and allocation patterns. In particular, residents of these areas express little support for strategies such as construction and growth moratoriums, mandatory water conservation programs, water transfers from low-to high-population areas, water marketing, or reallocations of water from agricultural to municipal/industrial uses. This rejection of water management strategies that would require a departure from “business as usual” with respect to water use and allocations severely restricts the capacity of these and similar communities to respond effectively should a severe sustained drought occur. 相似文献
997.
Michael K. Mount 《组织行为杂志》1984,5(4):271-279
Satisfaction with a performance appraisal system and the appraisal discussion was assessed by questionnaires administered to a random sample of managers and employees in a large multinational corporation. Stepwise regression and cross validation analyses were used to identify reliable linear composites for managers (n = 222) and employees (n = 368) on two dependent measures: overall experience with the appraisal system, and quality of the appraisal discussion. The results indicated differences in the aspects of the appraisal process which are related to satisfaction with the appraisal discussion, compared to satisfaction with the overall appraisal system. The results also indicated differences between managers' and employees' opinions regarding the appraisal system. Managers were found to be more satisfied than employees with most aspects of the appraisal system. And, the aspects of the appraisal system which were related to managers' and employees' satisfaction with the appraisal discussion were substantially different. 相似文献
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