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81.
ABSTRACT: The geology and fresh ground water lens development in a typical Pacific atoll are described together with a method for hydrogeological investigation. The fresh water resources of such lenses are investigated using Tarawa as an example. It is shown that simple steady state solutions cannot be realistically applied, and that despite the paucity of hydrogeological data, which is considered typical of such islands, practical nonsteady state solutions allow resource assessments. The susceptability of lens resources to drought conditions is demonstrated.  相似文献   
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83.
The human division of male and female sexes has profound unacknowledged consequences for behavior in organizations. Sex is not simply an individual difference (like eye color), but is an essential part played in life with others. This essay finds sex to be the main organizing principle of human life. Bringing this fact to light, the essay shows how we can begin to understand many perplexing problems of reconciling men and women in organizations today. Copyright © 2002 John Wiley & Sons, Ltd.  相似文献   
84.
The British Government is proposing a new system of single‐tier development plans for England and Wales, with clear implications for the strategic level of planning. This paper considers a proposal by the Committee of Inquiry into Town and Country Planning set up by the Nuffield Foundation, for a revised strategic planning network which includes a ‘local strategy’. The paper considers the lessons to be drawn from the use of regional reports in Scotland since the early 1970s and concludes on a note of caution for the Government's proposals.  相似文献   
85.
Rapid industrialization and population growth in the north Mexican desert city of Ciudad Juarez are placing a serious strain on the city's municipal water resources. Water deliveries and service area have more than doubled over the past decade, and plans for additional expansion are presently being implemented. This expansion is already contributing to water table declines and salinity increases in the Mexican portion of the Heuco Bolson, the sole source of water for the city. Continued mining of the limited fresh water reserves should produce serious water supply problems in the near future. New estimates of future water consumption incorporated into a digital aquifer simulation model indicate that these problems may show up much sooner than was anticipated in previous investigations. The results of this study point to the need to accelerate the gathering of basic data on alternative water resources. The problems faced by Cd. Juarez are illustrative of the kinds of difficulties likely to confront other rapidly developing cities of the arid zone.  相似文献   
86.
ABSTRACT: Recreation has produced substantial employment, incomes, economic development, and migration impacts since completion of the McCle-lan-Kerr Arkansas River Navigation System. These impacts support the influence of navigation, hydropower, flood control, and channel stabilization outputs on regional development. The marked success is not without substantial costs in public resources, including manpower which are devoted to recreational management. Increasing the share of financial resources obtained from recreational users and transfer of management responsibilities to nonfederal agencies, including private concessionaires is recommended.  相似文献   
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Over 1 million species around the world are at risk of extinction, and conservation organizations have to decide where to invest their limited resources. Cost-effectiveness can be increased by leveraging funding opportunities and increasing collaborative partnerships to achieve shared conservation goals. We devised a structured decision-making framework to prioritize species’ conservation programs based on a cost–benefit analysis that takes collaborative opportunities into account in an examination of national and global conservation return on investment. Conservation benefit is determined by modifying the novel International Union for the Conservation of Nature Green Status for Species to provide an efficient, high-level measure that is comparable among species, even with limited information and time constraints. We applied this prioritization approach to the Wilder Institute/Calgary Zoo, Canada, a nonprofit organization seeking to increase the number of species it assists with conservation translocations. We sought to identify and prioritize additional species’ programs for which conservation translocation expertise and actions could make the most impact. Estimating the likelihood of cost-sharing potential enabled total program cost to be distinguished from costs specific to the organization. Comparing a benefit-to-cost ratio on different geographic scales allowed decision makers to weigh alternative options for investing in new species’ programs in a transparent and effective manner. Our innovative analysis aligns with general conservation planning frameworks and can be adapted for any organization.  相似文献   
89.
The question of why so many people leave science, technology, engineering and mathematics (STEM) jobs continues to echo through social science research and Government policy. This is not surprising given the considerable investments into uptake and quality of STEM education and that STEM workers have a pivotal role to play in addressing current and future grand challenges. Yet, too many individuals with tertiary degrees in STEM—disproportionately women, racial minorities, and the underprivileged—leave or pursue careers in non-STEM fields. While demand for employment in STEM continues to grow, such persistent STEM defections present a significant challenge. We offer an integrative special issue of eight empirical articles capturing current thinking and evidence on employee retention and turnover, both within and beyond the realm of STEM. Our thematic analysis of the articles reveals overarching themes around the fundamental question of why people choose to stay in their jobs and why they leave. From this, we provide a future research agenda recognizing the myriad work and nonwork factors influencing the desire and ability to stay in one's chosen profession, particularly in critical sectors where gender and minority attrition rates prevail.  相似文献   
90.
A study was conducted to evaluate the association between PCBs in residential indoor air and in the serum of older, long time residents of three upper Hudson River communities. Samples of indoor air and of serum were collected from 170 persons 55 to 74 years of age, and analyzed for PCBs using glass capillary gas chromatography. After adjusting for age, BMI, cigarette smoking, and Hudson River fish consumption with multiple linear regression analysis, the results indicated statistically significant associations between concentrations in indoor air and serum for PCB-28, a lightly chlorinated congener common in air that accumulates in serum, and PCB-105. Duration of exposure was an important factor, since among persons who had lived in their home for 39 years or more, 11 of the 12 most commonly detected congeners were significantly correlated, as was their sum (∑ PCB). Significant associations between indoor air and serum PCB concentrations also were more likely when collected in cooler months and if the two samples were collected within 20 d of each other. The study is among the first to indicate that PCB concentrations characteristic of residential indoor air are associated with a detectable increase in body burden.  相似文献   
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