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921.
调查了水泥厂机立窑各类除尘设备的现状 ,结果表明 ,干法静电除尘器是目前机立窑烟尘治理的首选除尘器 相似文献
922.
在处理了部分有关资料的基础上 ,从发震断层旋性、历史地震类比、地震活动图像变化和地震序列特征等多方面对昆仑山口西 8.1级地震的余震活动趋势进行了讨论 ,结果表明 :本次 8.1级地震的最大余震震级可能为 6级左右 相似文献
923.
从供给角度对地震灾害国民经济体系易损性的分析 总被引:1,自引:0,他引:1
以投入产出分析为基础,从供给的角度提出了对地震灾害国民经济体系易损性分析方法,为经济体系生命线工程的确定和防灾、抗灾投入的有效实施提供了基础。 相似文献
924.
本文在分析湖北省局部地区自然疫源变化及疾病趋势的基础上,指出了南水北调中线工程可能对地氟病、血吸虫、疟疫、乙脑及其它水源性疾病所带来的影响,并提出了建设性的建议和对策。 相似文献
925.
926.
Competence in understanding and resolving environmental problems requires a curriculum that integrates traditional disciplines
with applied problem-solving skills and/or methods. Building upon the work of scholars who are calling for curriculum reform
so that students may understand better the ethical dimensions of environmental problems, we analyze the theory of using dialogic
writing to think and learn about the environment, and we provide examples of application of this technique. 相似文献
927.
Otis W. Templer 《Journal of the American Water Resources Association》1980,16(4):668-675
ABSTRACT: Rapidly increasing demand for recreational use of Texas' public waters is resulting in growing conflict between riparian landowners and the public. This paper examines the public access question, certainly one of the most poorly defined and understood areas of Texas water and property law. Since the appropriation acts of the late 1800's, most surface waters are owned by the state, and are held in trust for the benefit of the people. While there is no express statutory authority giving the general public the right to use these waters, there is extensive, if often conflicting, case law recognizing such rights on navigable streams. It is equally well established that the public may not gain access by crossing private property. Definition of public and private rights is complicated by the fact that Texas land grants (with their attendant property rights) have emanated from Spain, Mexico, the Republic of Texas, and the state. Obstacles imposed by riparian landowners to public entry, use and passage, as well as spatial aspects of access, are also considered. Because public access rights are based on the peculiar circumstances of each case, it is difficult to establish general legal principles, and there is almost no reliable information to aid the recreation-seeking public. A clear legislative enunciation of public rights appears politically infeasible at present, the most immediately attainable goal lying in the area of better public education. 相似文献
928.
David A. Stephenson 《Journal of the American Water Resources Association》1971,7(5):1038-1047
ABSTRACT. Evaluation of lakes as they are related to groundwater flow systems is of special concern prior to efficient development and planning operations. Both naturally occurring and artificially created lakes are being developed rapidly as recreational and residential areas. Simultaneously, field verification of theoretical groundwater flow system behavior has progressed to the point where hydrogeologists trained to understand basic concepts of flow-system analysis can begin to broaden their research and service base, and to work closer with planners, developers, and engineers. It is suggested that particular efforts be directed toward a greater evaluation of physical, chemical, and biological aspects of potentially developable lake sites to aid in selecting use patterns in accord with these factors. Many lake developments are not in harmony with the physical environment. The resulting misuse of resources is often expressed as accelerated eutrophication of lakes, or by quality degradation of shallow groundwater flow systems contiguous to them. Lakes can no longer be considered as separate entities. Methodology for investigating the interchange of surface and near-surface water is adequate however, the application of known interchange relationships is inadequate. . 相似文献
929.
Jerry R. Rogers Robert S. Gemmell 《Journal of the American Water Resources Association》1971,7(3):581-591
ABSTRACT A critical examination of single gage site, monthly streamflow statistical characteristics for two southern Illinois rivers, an Oklahoma river and a Texas river was made using a digital computer at Northwestern University. High flow variability for the rivers was evident in that, for the rivers tested, 8 to 11 months had coefficients of variation in excess of unity. The gamma distribution was not as efficient as the normal distribution for fitting power or logarithmic transforms of the historical monthly flow data (i.e., F1-0, F0-5, F0-25, Fa125, F0.085, and log F). No single transform to a normal distribution was adequate for all twelve monthly flows, since definite seasonal grouping patterns were found for the four rivers examined. The highly variable flow in the low-flow season(s) indicated much more skewness than was typical of the remainder of the year. For the low-flow seasons, the higher-root (smaller exponent) transforms were particularly useful. Flows were generated from a linear regression model of lag one utilizing two or more transforms for the twelve periods. The definite seasonal patterns found historically were reproduced quite well in the generated streamflows. The effect of a change in data transform from one season to the next was insignificant after one month. Thus the use of different transforms within the year did not bias the results from the linear regression model appreciably, but did help in reproducing the seasonal distribution pattern. The technique seems especially well suited for rivers with highly variable flows. 相似文献
930.
Jared J. Hardner 《Journal of the American Water Resources Association》1996,32(6):1361-1366
ABSTRACT: A pilot study was conducted to test the potential of the Contingent Valuation Methodology (CVM) to reveal the value of non-market goods in a partially monetized subsistence economy. CVM was used to estimate the willingness to pay, in the form of labor, for potable drinking water in a rural river-based community located in the Esmeraldas state of northwest Ecuador. Surveys were administered by personal interviews with families living along the waterways of the Santiago river system who used river water for cooking, drinking, washing, and waste disposal. The mean willingness to pay represented over 23 percent of real income, or 1.4 days per week for a period of one year. Results of multiple regression analysis identified the history of water-related health problems and the number of working adults in a household as significant determinants of willingness to pay. Using a non-monetary, rather than a monetary measure of willingness to pay may provide a more accurate representation of value in a subsistence economy where the use of money is limited. The potential for CVM to measure the benefits of non-market goods in rural developing regions whose economies are only partially monetized is demonstrated. 相似文献