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361.
将含有大量悬浮物的洗气箱废水进行初级沉降后,约3/4的废水返回洗气箱用作洗涤水,其余的与洗气塔废水混合进地沉降池去除悬浮物,上清液送至生物滤池进行生化处理去除含氰人合物其他有机物。生化出水经絮凝、澄清后回用于洗气箱和洗气塔实现了废水闭路循环。他 相似文献
362.
363.
Rosanna L. Mattingly Edwin E. Herricks Douglas M. Johnston 《Environmental management》1993,17(6):781-795
The environmental impact of loss of natural stream and riparian habitat is of concern throughout the United States and Europe.
Environmental impacts related to such activities as channelization of and levee construction along streams and rivers are
particularly apparent in the Midwestern United States. The objective of the research presented here was to delineate the extent,
relative degree of impact, and implications for management of channelization and levee construction along watercourses located
in the state of Illinois. According to records maintained through the Illinois Streams Information System data base (Illinois
Department of Conservation), nearly 25% of surface water resources in the state have been modified directly by channelization
and/or levee construction. Reviews of agency records, elaboration of case histories, interviews with agency personnel, and
inspections of impacted sites indicated that these alterations have occurred without the benefit of effective mitigation.
Although permit records may provide suggestions for mitigation to be incorporated in the design of a particular project, permits
issued generally do not require even minimal instream habitat and bank stabilization efforts in conjunction with channel alteration.
Information derived from policy and case study analyses suggests that institutional constraints, rather than lack of particular
understanding about mitigation, provide major barriers to protecting the state's surface water resources in terms of regulatory
review, policy interpretation and implementation, and project evaluation. Recommendations for environmental management efforts
regarding these and similar channel alterations are elaborated from these findings. 相似文献
364.
本文论了宰屠废水的水质特征,我国屠宰废水处理的主要工艺。侧重阐述了生物法与“组合法”处理屠宰废水的运行机理与处理效果。在对比了这两种方法各自优缺点的基础上,作者推荐采用“厌氧(兼氧)-好氧生物法”。 相似文献
365.
高压旋喷灌浆法是本世纪70 年代发展起来的地基处理新技术,在砂性土和粘性土等软弱地层加固工程中已得到广泛应用,但在含有碎石的淤泥质土及穿过它对其下淤泥的加固尚少见,笔者简要介绍了采用钻灌分开两大工序的新双管法及其成功完成加固任务的事例。 相似文献
366.
导流电凝聚法脱除印染废水色度的研究 总被引:11,自引:1,他引:10
阐述了导流电聚法处理废水的基本原理。采用该法处理印染废水,通过试验确定了废水电解脱色的最佳工艺条件。处理后印染废水的色度,pH,COD均达到国家排放标准。该法操作简单,电耗低,产生废渣量少,无二次污染。 相似文献
367.
日本城市化中的耕地变动与经验 总被引:20,自引:2,他引:18
日本是一个国土面积狭小、耕地资源稀缺的国家。然而,在人均土地资源极为有限的条件下,日本在较短时间内达到了高度城市化,同时付出了较小的用地代价。在其整个城市化进程中,日本还出现了三个耕地面积增长时期。尽管各时期增长原因不尽相同,但却反映出耕地面积变动与城市化发展的密切关系。事实表明,日本选择了一条节约有限土地资源的城市化发展道路,这些经验对我国城市化发展中的耕地利用与保护有积极的借鉴意义。 相似文献
368.
Development and Adoption of a Simple Nonpoint Source Pollution Model for Port Phillip Bay,Australia 总被引:1,自引:0,他引:1
New computing tools and approaches allow tailored development of software to meet the needs of environmental managers. The processes required for such tailoring fit well with adaptive management concepts where, as knowledge and system understanding develop among managers, the software can be developed or replaced to match. This paper reports on development and adoption of a simple nonpoint source pollution modeling tool, including technical aspects of data support for modeling and social aspects of software design. The software, named FILTER, used a unit load model to generate expected pollutant loads from subcatchments of Port Phillip Bay, Australia. Monitoring data were used for calibration to modify the delivery of generated pollutants to receiving waters. Spatial, tabular, and charting software components were used to provide alternative forms of output visualization. FILTER was developed using a process that resulted in manager-stakeholders taking responsibility for setting of model parameter values and operation of the user interface, thereby encouraging uptake. The inclusive development process, tailoring of the software to manager needs and styles of usage, and matching of model complexity to data and knowledge, resulted in a successful application that has become the current agreed system representation among disparate stakeholder organizations. 相似文献
369.
A relative significance factor (f
i
) of an impact category is the external weight of the impact category. The objective of this study is to propose a systematic
and easy-to-use method for the determination of f
i
. Multiattribute decision-making (MADM) methods including the analytical hierarchy process (AHP), the rank-order centroid
method, and the fuzzy method were evaluated for this purpose. The results and practical aspects of using the three methods
are compared. Each method shows the same trend, with minor differences in the value of f
i
. Thus, all three methods can be applied to the determination of f
i
. The rank order centroid method reduces the number of pairwise comparisons by placing the alternatives in order, although
it has inherent weakness over the fuzzy method in expressing the degree of vagueness associated with assigning weights to
criteria and alternatives. The rank order centroid method is considered a practical method for the determination of f
i
because it is easier and simpler to use compared to the AHP and the fuzzy method. 相似文献
370.
This paper describes an application of multiple criteria analysis (MCA) in assessing criteria and indicators adapted for a
particular forest management unit. The methods include: ranking, rating, and pairwise comparisons. These methods were used
in a participatory decision-making environment where a team representing various stakeholders and professionals used their
expert opinions and judgements in assessing different criteria and indicators (C&I) on the one hand, and how suitable and
applicable they are to a forest management unit on the other. A forest concession located in Kalimantan, Indonesia, was used
as the site for the case study. Results from the study show that the multicriteria methods are effective tools that can be
used as structured decision aids to evaluate, prioritize, and select sets of C&I for a particular forest management unit.
Ranking and rating approaches can be used as a screening tool to develop an initial list of C&I. Pairwise comparison, on the
other hand, can be used as a finer filter to further reduce the list. In addition to using these three MCA methods, the study
also examines two commonly used group decision-making techniques, the Delphi method and the nominal group technique. Feedback
received from the participants indicates that the methods are transparent, easy to implement, and provide a convenient environment
for participatory decision-making. 相似文献