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291.
Wynn R. Walker Caylord V. Skogerboe Thoms L. Huntzinger 《Journal of the American Water Resources Association》1974,10(5):845-859
ABSTRACT: Urbanizing river basins in the west are encountering serious water quality degradation resulting from the expanded water utilization. In order to avoid aggravating such conditions, water quality controls need to be implemented. The important questions are, therefore, where and how to impose such constraints on the urban and agricultural sectors to achieve the desired level of pollution control. An application of the model developed to address such questions is made in the Utah Lake drainage area of Central Utah as a test of the model's utility. The region is subdivided into five major sub-basins containing both municipal and agricultural water demands. A submodel of each sub-basin is developed which optimizes the water quality control strategies by linking the urban to the agricultural uses and then evaluating the levels of control for each sector. From these results, a cost-effectiveness function for each sub-basin is generated. By jointly considering the cost-effectiveness relationship for each sub-basin, an optimum policy for the entire basin is determined. 相似文献
292.
Carl Blair Housley 《Journal of the American Water Resources Association》1972,8(4):679-684
ABSTRACT. Federal guidelines for the establishment of water quality standards prohibit degradation of the properties of all or part of the nation's aquatic resources. It is probably correct that streams, lakes and aquifers should be free of toxic substances while non-poisonous deposits should be abated. However, an extreme opposing position is held by some proponents of pollution who intend to continue discharging waste materials until forced to stop. Although it would seem otherwise, the underlying problem is that polluters' points of altercation possess merit in particular instances. Accordingly, efficient abatement will require that appropriate laws be formulated in such a manner that the nature of economic reasons for the disposal of waste materials be disclosed. Moreover, the technological ability to create byproducts from these particular elements or compounds can advance only over time. This, coupled with the fact that scientists have not developed inexpensive treatment methods which are totally effective, justifies more flexible formal regulations. Excessive rigidity of standards could impose a burden on polluters that is greater than the cost to society which the damaging firm or individual is generating. On the other hand, uniform rules in some cases could be considered so lenient as to allow flagrant contamination which unduly injures downstream users. 相似文献
293.
Ian Christoplos 《Disasters》1999,23(2):125-138
A variety of codes and standards for humanitarian assistance have been put forth in recent years. Many NGOs have agreed to abide by these codes. There is uncertainty, however, about if and how these codes are actually being put into practice. Have we moved from words to action? One response to this concern has been a proposal to establish a humanitarian ombudsman. This paper analyses two choices facing an eventual ombudsman: whether to attempt to take punitive actions to enforce the codes and standards, or whether instead to facilitate agencies' own internal efforts to improve accountability to their beneficiaries. It proposes a pluralistic approach, wherein a variety of methods, structures and local perceptions are accepted as potentially appropriate, but where a clear moral stance is still maintained. Some suggestions are outlined for how flexible forms of policy analysis may be used to combine an acceptance of the validity of a vast range of humanitarian actions while still retaining a strong stance against practices that may harm beneficiaries or feed the causes of conflict. Realism about each agency's room for manoeuvre is essential, especially local institutions. A modest but principled stance will involve helping actors to consider the impact of their work on conflict and to find ways to improve the quality of their interventions as perceived by beneficiaries. 相似文献
294.
295.
首先从现代环境保护的内在逻辑入手,指出我国环境法治正处于从外生型向内生型转变,并认同以排污许可为核心的环境许可制度应成为我国环境治理的核心制度。接着对环境许可制度进行基本的理论分析和简单框架梳理,认为环境许可制度是以法治完善和科技发展为支撑的,在此基础上需要进一步的内容细化和体系构建,并强调在风险预防原则下,环境许可不应局限于排污许可制度。然后分析了欧盟与德国在环境许可一体化上的趋势与不同,进而提出我国环境许可制度的趋势。探讨了与环境许可制度紧密相关的环境技术标准制度,认为基于技术的环境标准面临内生性、系统化和动态完善的要求,环境许可制度需要面向环境质量达标体系转型。本文还分析了德国环境治理理念的转型变革与许可制度衔接的经验。最后,小结对我国环境许可制度的启示。 相似文献
296.
日本20世纪60年代开始经济迅速发展,但同时也带来了严重的大气污染问题。文章简单介绍了日本大气污染物的分类,再次分别从固定源和流动源二个方面梳理了日本氮氧化物的排放标准,并概述了日本实施氮氧化物排放标准的成效。最后总结了日本氮氧化物排放标准的特点:排放标准是根据排放氮氧化物的设备或设施的不同来区分的,且时间上都体现了新源比旧源严格的思想;日本的排放标准非常详细具体;汽车尾气的污染问题是日本大城市的氮氧化物污染难以改善的重要原因。 相似文献
297.
复合高效微生物处理高含盐石油开采废水 总被引:12,自引:0,他引:12
石油开采废水中高含盐量对微生物处理有强抑制作用。有针对性地筛选驯化了耐盐复合高效处理菌群对大港油田石油开采废水进行有机物降解,在废水的氯离子含量为20000~36000mg/L,COD浓度l600~4000mg/L范围内,高含盐量对耐盐复合高效微生物无明显抑制作用,结合物化处理方法COD去除率稳定在90%左右,处理后水达到二级排放标准。 相似文献
298.
In the United States, each state is required to list water resources that are declared to be impaired under guidelines set by the Clean Water Act. Measurements are typically collected on a number of chemical constituents and compared with a standard. If there are too many measurements exceeding the standard, then the site is declared impaired. The approach is non-statistical but similar to a Binomial test. The Binomial approach would convert the measurements to binary data then test if the proportion exceeding the standard is excessive. Both methods convert measurements to binary values hence exclude potentially important information in the data. We present a statistical approach using a Bayesian model that uses the raw data instead of the binary transformed data. The population distribution of a family of location-scale parameter models is studied under the model. Posterior distributions from the Bayesian analysis are used in the decision-making process and error probabilities for the Bayesian and the Binomial approaches are compared for a normal population. 相似文献
299.
Salvatore Collura Bruno Azambre Gisèle Finqueneisel Thierry Zimny Jean Victor Weber 《Environmental Chemistry Letters》2006,4(2):75-78
In this paper we present, for the first time, data on the combustion of Miscanthus × Giganteus straw and pellets. We found that the heating value of Miscanthus is 17.744 MJ/kg. The gaseous emission indices of SO2, NO
x
and total organic carbon (TOC) in the exhaust are reported and compared with the European standards for biomass boilers. On the basis of our results, it is possible to evaluate a net energy yield between 152 and 326 MJ/hectare/year for the cultivation of Miscanthus with an energy balance estimated to be in the range of 7.7–15.4. According to the presented results, it seems reasonable to consider Miscanthus as a promising candidate as alternative fuel. 相似文献
300.
Montserrat Fuentes Arin Chaudhuri David M. Holland 《Environmental and Ecological Statistics》2007,14(3):323-340
We develop a spatial statistical methodology to design national air pollution monitoring networks with good predictive capabilities
while minimizing the cost of monitoring. The underlying complexity of atmospheric processes and the urgent need to give credible
assessments of environmental risk create problems requiring new statistical methodologies to meet these challenges. In this
work, we present a new method of ranking various subnetworks taking both the environmental cost and the statistical information
into account. A Bayesian algorithm is introduced to obtain an optimal subnetwork using an entropy framework. The final network
and accuracy of the spatial predictions is heavily dependent on the underlying model of spatial correlation. Usually the simplifying
assumption of stationarity, in the sense that the spatial dependency structure does not change location, is made for spatial
prediction. However, it is not uncommon to find spatial data that show strong signs of nonstationary behavior. We build upon
an existing approach that creates a nonstationary covariance by a mixture of a family of stationary processes, and we propose
a Bayesian method of estimating the associated parameters using the technique of Reversible Jump Markov Chain Monte Carlo.
We apply these methods for spatial prediction and network design to ambient ozone data from a monitoring network in the eastern
US. 相似文献