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941.
942.
Prof. Dr. A. Jacobi 《Die Naturwissenschaften》1913,1(29):681-685
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FAE威力评价方法与目标防护分析 总被引:5,自引:0,他引:5
对燃料空气炸药(FAE)爆炸场特性进行了分析;从冲击波超压- 冲量毁伤准则出发,提出一种以靶板毁伤效应为评价依据的FAE威力评价方法,并结合易损性等效原理,对不同毁伤等级下目标防护问题进行了分析 相似文献
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Cs. Vadadi-Fülöp D. Türei Cs. Sipkay Cs. Verasztó Á. Drégelyi-Kiss L. Hufnagel 《Environmental Modeling and Assessment》2009,14(5):563-576
In the years 2004 and 2005, we collected samples of phytoplankton, zooplankton, and macroinvertebrates in an artificial small
pond in Budapest (Hungary). We set up a simulation model predicting the abundances of the cyclopoids, Eudiaptomus zachariasi, and Ischnura pumilio by considering only temperature and the abundance of population of the previous day. Phytoplankton abundance was simulated
by considering not only temperature but the abundances of the three mentioned groups. When we ran the model with the data
series of internationally accepted climate change scenarios, the different outcomes were discussed. Comparative assessment
of the alternative climate change scenarios was also carried out with statistical methods. 相似文献
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Summary Biosphere reserves are protected areas of representative environments internationally recognised for their value for conservation and for their ability to provide the scientific knowledge, skills and human values to support sustainable development. Biosphere reserves — as a part of the UNESCO programme Man and the Biosphere (MAB) — make up a world-wide network sharing research information on ecosystem conservation, management and development. They include strictly protected core-areas — representative examples of natural or minimally disturbed ecosystems. Core areas are surrounded by buffer zones in which research, environmental education and training and recreation can take place. Buffer zones are, in turn, surrounded by transition areas, large open areas where the aim is to ensure rational development of the natural resources of the region. At present, twelve biosphere reserves are designated in Germany, covering in all an area of 11,589 km2. The role of biosphere reserves to support sustainable development in Germany and Europe is discussed.Karl-Heinz Erdmann is a geographer and Deputy Secretary General at the Secretariat of the German National Committee for the UNESCO Programme on Man and Biosphere (MAB), Federal Agency for Nature Conservation. He is also a Committee Member of the Society for Man and Environment (GMU). 相似文献
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This paper reports the development and application of an analytical method in which both polyethylene glycol ethers or polyethylene glycols are converted into ethylene dibromide via treatment with concentrated hydrobromic acid/glacial acetic acid (1:1) at 150°C for 3 hours. This method can detect <1 ppm of the surfactant in biological tissues, however, the practical utility of the technique is dependent on the solvent and reagent purities and the various cleanup methods which include base hydrolysis, high pressure liquid chromatography and Florisil or acidified Florisil column chromatography. 相似文献