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481.
Verifying an Extinction Debt among Lichens and Fungi in Northern Swedish Boreal Forests 总被引:5,自引:0,他引:5
Abstract: Destruction and fragmentation of natural habitats results in small species populations that face increased risk of extinction. A time delay may be involved in the regional extinction of species, and the number of species that eventually may go extinct in the future is called the "extinction debt." In boreal Sweden, we examined whether the number of epiphytic crustose lichens and wood-inhabiting fungi in old-growth forest remnants diverges from species richness levels in forest patches that have been naturally isolated for millennia. An excess of species in forest remnants could indicate the presence of an extinction debt. Observed species richness in 32 old-growth forest remnants (also called woodland key habitats [WKHs]) was compared with predicted species richness. To predict species richness we used regression models based on data from 46 isolated old-growth forest patches in a forest-wetland matrix. The reference landscape is ancient and assumed to reflect the conditions of insular floras in dynamic equilibrium. Stand factors constituted predictive variables in the models. The observed number of lichen species was higher than expected (i.e., an extinction debt among lichens may exist). By contrast, there was no significant difference between observed and expected species richness among wood-inhabiting fungi. The species richness of wood-inhabiting fungi has adjusted to the changes in forest and landscape structure more rapidly than the species richness of lichens. Differences in substrate dynamics between epiphytes on living trees and species growing on decaying logs might explain the difference between species groups. The results also indicate that population densities of red-listed species were low, which may result in continuing extinctions of red-listed species. The importance of WKHs might be overvalued because species may be lost if conservation efforts consider only protection and preservation of WKHs. 相似文献
482.
483.
工业企业噪声环境影响评价中的测点布设与测量、预测时段的选择 总被引:1,自引:0,他引:1
指出工业企业噪声环境影响评价中,由于测点与测量时段选择的不妥,导致测量及预测值“以偏代全”的结果;提出了测点合理布设与测量、预测时段科学选择的原则,以使测量与预测结果能较好地符合项目建成前后噪声环境实际状况。 相似文献
484.
Risk management of terrorist attacks in the transport of hazardous materials using dynamic geoevents
Maria Francesca Milazzo Giuseppa Ancione Roberto Lisi Chiara Vianello Giuseppe Maschio 《Journal of Loss Prevention in the Process Industries》2009,22(5):625
This paper focuses attention on emergency management associated with a terrorist attack in the transport of hazardous materials in urban areas. The case study is in an urban area, a potential target for terrorist attacks due to its high vulnerability. Since it is not possible to predict where and when an attack will occur, the risk associated with terrorism is complex. It is only possible to identify the critical points for potential actions where counter measure must be applied. In the case of incidents which evolve relatively slowly, mitigation actions can be applied. The use of dynamic geoevents permits the immediate location of the event on a georeferenced map and the possibility of having a dynamic evolution of the scenario and of the number of people involved. The dynamic scenario has been created using the output of a consequence simulation code and a GIS software. Some assumptions were necessary but, since the aim of the paper is to define the procedure for the construction of the dynamic geoevent, these can be considered acceptable. The method will be further implemented in future. 相似文献
485.
It is well recognized that a trigger point is a functional, rather than an anatomical, entity. It is known that a significant
fraction of both acute and chronic pain experience is myofascial in nature. This paper is aimed to discuss the potential of
using permanent magnets placed over the trigger points, which are associated with that referred pain, to be a tool for pain
relief. This approach is even more important in patients with various disabilities and experiencing chronic sacro-iliac and/or
low back pain. It appears that the trigger points represent a plausible physiological/tissue “window” and/or pathways, which
allow the magnetic fields to penetrate through physiological barriers, and thus returning injured tissues to the homeostatic
state. These “tissue windows” represent physiological “entrance points” for eventual exogenous stimulations, mainly physical
by nature, to enter the body. There is evidence that the application of magnetic fields (via permanent magnets) on trigger
points is more effective for pain relief as compared to application to other body surface area. The systemic effects at which
the results are manifested at sites distant from application area is also considered when discussing effects of magnetic fields
applied on trigger points. Ion transport is considered as central to the integrity and proper functioning of nerve excitability
and muscle contraction. Any disruption of their normal function would directly and markedly affect human neurosensory and
neuromotor performance. Biophysical phenomena associated with modification of ion transport are in the range of weak stimuli.
Therefore, electrophysiological changes in the functions of the so-called ion channels, are among the more (perhaps the most)
sensitive indicators to detect and quantify physiological effects of electromagnetic fields. 相似文献
486.
487.
《Process Safety and Environmental Protection》2014,92(6):583-589
Chemical industrial areas or so-called chemical clusters consist of hundreds, and sometimes thousands, of chemical installations situated next to each other. Such areas can thus be seen as the summation of a large number of structures exhibiting danger to a certain degree for initiating or continuing accident domino effects or knock-on effects. In this article, an approach to investigate in a systemic way the vulnerability of each installation within the larger chemical cluster context, is developed. Our suggested method results in a prioritization of chemical installations with respect to their vulnerability for domino effects. The method can be used for intelligently designed protection of chemical industrial areas against terrorist attacks. 相似文献
488.
HSE管理体系有效运行的几个重点 总被引:1,自引:0,他引:1
于瑾 《安全.健康和环境》2004,4(8):24-26
结合工作实际,探讨了影响HSE管理体系有效运行的关键因素,指出领导重视、HSE培训、检查考核及严格遵守程序文件所规定的职责是体系能否持续改进、不断完善的重点. 相似文献
489.
为了研究多米诺效应中多事故点协同作用的后果,将并联系统概率模型运用到贝叶斯概率计算过程中,体现出多事故点协同作用对多米
诺效应传播的概率影响;后果分析部分从人、物、环境3个方面出发,对事故的后果影响以及事故预防提出建议措施。最后运用模型对实例进行
了应用分析,结果表明:多事故点协同作用下储罐的多米诺失效概率增大,罐区危险性增强,可以通过对储罐设置安全屏障等措施,有效的切
断导致事故最大概率的链条。 相似文献
490.
固体废物属性鉴别在进口废物管理方面具有重要作用,是口岸加强进口废物监管的重要技术支持依据。在进口物品固体废物属性鉴别中,各鉴别机构可能会遇到很多难以把握的问题。对固体废物属性鉴别关键问题进行思考,包括首要解决的问题、标准或规范的使用、鉴别的三个“键节点;过程产物的判断、特性分析、二次再生资源加工产物的判断等6个方面。 相似文献