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951.
Specifying information needs: improving the working methodology 总被引:1,自引:1,他引:0
Jos G. Timmerman Joop Boer Matthijs Hisschemöller Wim Mulder 《Regional Environmental Change》2001,2(2):77-84
Specification of information needs is an important step in the design of monitoring networks. Within the framework of Monitoring
Strategy 2000+, a programme of the Dutch Directorate General of Public Works and Water Management (Rijkswaterstaat) which
seeks to provide innovation in the monitoring sector, a method has been developed to link water management policy to monitoring
through specification of information needs. Over the past 2 years, this method has been applied in several projects within
the Rijkswaterstaat organisation. Use of this method has led to improvements in the monitoring practice and was judged very
positively by the people involved. Nevertheless, the main obstacle to employing the method was the actual translation of policy
matters into information products. A special study is carried out, focusing on this aspect within the method, to provide the
participants of a project with a mental framework that enables them to clearly specify their information needs. The major
requirements for this mental framework are that all participants have a clear view of the process (system), and that they
are able to relate their contribution to this process and to the contributions of others (transparency). The first step of
the process is to focus the attention of stakeholders on the information they will actually need for decision-making. The
next step is to confront the different expressed opinions through the method of the 'devil's advocate', which implies criticising
the results of the first step by finding as many as possible arguments against these opinions. This should force the stakeholders
to better specify their arguments. The method, its improvements and the results of one pilot project will be discussed in
this paper.
Electronic Publication 相似文献
952.
罗善明 《中国安全科学学报》2001,11(6):66-68
对有限空间中的淹没非自由射流流压力场的数值解法进行了较为详细的研究和分析 ,并建立了相应的流场力学模型和压力解的第二类边界条件 ,给出了流场的矩形网格几何和边界标记。文中指出 ,精确的压力解只能从泊松形式的压力方程得到 ,且与边界相邻的点和内点应分别采用不同的方程进行求解 相似文献
953.
954.
Kathryn B. McNamara Mark A. Elgar Therésa M. Jones 《Behavioral ecology and sociobiology》2008,62(9):1433-1440
Species where most but not all females mate monandrously can provide insight into the potential factors both promoting and
restricting polyandry. Polyandry is typically explained by direct and/or indirect benefits models; however, polyandry may
also confer costs via sexually antagonistic processes. The fitness of polyandrous and monandrous females may also vary with
environmental conditions, such as availability of water. For some lepidopterans, water is a vital resource that increases
fecundity and may be a direct benefit of multiple mating. Male lepidopterans transfer large spermatophores that may be an
important water source for females, particularly for species living in water-depauperate environments. In such species, multiple-mating
females may increase their reproductive output. We examined the fitness consequences of multiple mating in the almond moth,
Cadra cautella. Males transfer substantial spermatophores; these have a large chitinous process attached, which decrease female longevity.
To assess the impact of female mating treatment and water availability on female fitness, females mated once or twice, either
with the same or different males, with half the females in each treatment receiving water. Water-fed females had dramatically
increased fecundity, but we found no fitness benefits of multiple mating. Male longevity decreased with increased mating frequency
and potentially his level of reproductive investment. Water-deprived females that mated twice died sooner than once-mated
females, while multiple-mating females that received water lived longer than their water-deprived counterparts. It is interesting
to note that the male’s spermatophore process did not affect female fitness or longevity. Why polyandry is maintained in this
species is discussed. 相似文献
955.
Evaluation of a Market in Wetland Credits: Entrepreneurial Wetland Banking in Chicago 总被引:1,自引:0,他引:1
Abstract: With the rise of market‐led approaches to environmental policy, compensation for permitted discharge of dredge or fill material into wetlands under Section 404 of the U.S. Clean Water Act has been purchased increasingly from entrepreneurial third‐party providers. The growth of this practice (i.e., entrepreneurial wetland banking) has resolved many challenges associated with wetland compensation. But it has also produced (1) quantifiable temporal loss of wetland ecological functions, (2) spatial redistribution of wetland area, and (3) a degree of regulatory instability that may pose a threat to entrepreneurial compensation as a sustainable component of wetland‐compensation policy. We used achieved compensation ratios, lapse between bank credit sale and the attainment of performance standards, distance between impact and bank site, and changes in bank market area to examine these 3 factors. We analyzed data from a census of all such transactions in the Chicago District of the U.S. Army Corps of Engineers, compiled from site visits, Corps databases, and contacts with consultants and Section 404 permittees. Entrepreneurial banking provided compensation at a lower overall ratio than nonbank forms of compensation. Approximately 60% of bank credits were sold after site‐protection standards were met but before ecological performance standards were met at the bank site. The average distance between bank and impact site was approximately 26 km. The area of markets within which established banks can sell wetland credits has fluctuated considerably over the study period. Comparing these data with similar data for other compensation mechanisms will assist in evaluating banking as an element of conservation policy. Data characterizing the performance of entrepreneurial wetland banks in actual regulatory environments are scarce, even though it is the most established of similar markets that have become instrumental to federal policy in administering several major environmental protection laws. 相似文献
956.
V. M. Shestopalov V. A. Ivanov A. S. Bohuslavsky S. I. Kazakov 《Journal of Coastal Conservation》2008,12(4):169-179
The main engineering-geological hazards and their factors of the Mountain Crimea coastal region are considered. A characteristic
shore line site of Cape Kikineiz and its neighboring coastal area near the Katsiveli settlement has been studied in more detail.
The important characteristic of the site is a high diversity of geological conditions with numerous manifestations of dangerous
engineering-geological processes: shore and hydrological network abrasion, loss of slopes and rocks stability, etc. These
processes have intensified during the last decades under the influence of natural and man-induced factors. The results of
preliminary study of geo-environmental situation of the area are presented. The program for further research and possible
recommendations for rational coastal hazard management and area ecological state improvement are outlined. 相似文献
957.
A health risk assessment for fluoride in Central Europe 总被引:4,自引:0,他引:4
Fordyce FM Vrana K Zhovinsky E Povoroznuk V Toth G Hope BC Iljinsky U Baker J 《Environmental geochemistry and health》2007,29(2):83-102
Like many elements, fluorine (which generally occurs in nature as fluoride) is beneficial to human health in trace amounts,
but can be toxic in excess. The links between low intakes of fluoride and dental protection are well known; however, fluoride
is a powerful calcium-seeking element and can interfere with the calcified structure of bones and teeth in the human body
at higher concentrations causing dental or skeletal fluorosis. One of the main exposure routes is via drinking water and the
World Health Organisation currently sets water quality guidelines for the element. In Central Europe, groundwater resources
that exceed the guideline value of 1.5 mg l−1 are widespread and effects on health of high fluoride in water have been reported. The aim of the current project was to
develop a geographic information system (GIS) to aid the identification of areas where high-fluoride waters and fluorosis
may be a problem; hence, where water treatment technologies should be targeted. The development of the GIS was based upon
the collation and digitisation of existing information relevant to fluoride risk in Ukraine, Moldova, Hungary and Slovakia
assembled for the first time in a readily accessible form. In addition, geochemistry and health studies to examine in more
detail the relationships between high-fluoride drinking waters and health effects in the population were carried out in Moldova
and Ukraine demonstrating dental fluorosis prevalence rates of 60–90% in adolescents consuming water containing 2–7 mg l−1 fluoride. 相似文献
958.
分析和阐明地表水环境质量灰关联评价中关联度向量r中各分量的信息荷载,在满足定量、连续、分级的条件下构造了水环境质量系数C,C由首数水质级别数K和尾数水质差异E组成。水环境质量系数既能表示水质级别,又能准确区别同级水质差异。在应用特例中介绍了模糊级别的区分和级别跳跃现象。最后介绍了应用中注意的问题。 相似文献
959.
地下水环境质量评价的一种新方法--集对分析法 总被引:19,自引:0,他引:19
提出了一种新的地下水环境质量评价模型———集对分析法。该方法是一种处理不确定性问题的理论,其模型数学表达简单,物理意义明确,所含意义深远。研究结果表明:集对分析法简便易行,评价结果准确,在环境质量综合评价中具有广泛的实用价值。 相似文献
960.