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41.
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Georg P. Frosch Joachim E. Tillich Ralf Haselmeier Manfred Holz Egon Althaus 《Geothermics》2000,29(6):68
Pulsed-Field-Gradient–Nuclear Magnetic Resonance (PFG–NMR) is an interesting method to determine microscopic but volumetrically averaged properties of pore space. In the present paper a number of sandstone samples, taken from drill cores of geothermal wells in North Germany, have been investigated. The time-dependent self-diffusion of water molecules in their confined geometry is used to probe the pore space. The short-time behaviour of the self-diffusion coefficient (anomalous diffusion) in the porous matrix allows the determination of the surface-to-pore volume ratio S/Vp. At long diffusion times, molecules scout the tortuosity of the interconnected pore space of the sandstones. The NMR results were compared with data from petrographic image analysis (PIA), adsorption experiments and electric conductivity measurements. The PFG–NMR measurements give surface-to-pore volume ratios S/Vp that are comparable to those estimated with the petrographic image analysis. The tortuosities match in most cases data from conductivity measurements, so the PFG–NMR is regarded as an appropriate tool to determine this quantity. The results are not influenced by the adherence of ‘scout-molecules’ to the pore walls. The surface-to-pore volume ratios and tortuosities were used to calculate permeabilities of the systems of interest, which were in good agreement with measured core-plug permeabilities. Results of additional NMR relaxation experiments are used to obtain adsorption isotherms for cations at active surface sites. 相似文献
43.
Salman M. A. Salman 《国际水》2013,38(4):580-585
Abstract International rivers serve a number of purposes, the most obvious are the navigational and non-navigational uses. Less noticed is the fact that international rivers are also used to delimit boundaries between nations. The immediate question that would arise is: Where are such boundaries actually drawn across the river? Boundaries, however, are established by treaties and the answer to this question is often included in the interpretation of treaties delimiting such water boundaries, taking into account the special characteristics of the international river. Indeed, this has been the case regarding the boundaries across the Chobe river between Botswana and Namibia. Determining where such boundaries lie would result in deciding to whom a disputed Island, the Kasikili/Sedudu, belongs. In a praiseworthy step, the two countries agreed to take their dispute over the Island, after failure to resolve it through negotiations, to the International Court of Justice. This paper discusses the uses of international rivers as boundaries, and reviews the dispute between Botswana and Namibia, and the decision of the Court thereon. 相似文献
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医院建筑作为最复杂的民用建筑之一,能耗非常巨大,建筑节能变得尤为重要。本文结合一次研讨活动的内容和考察实例,介绍德国绿色医院建筑节能更新的背景和目的,对四种常见模式进行粗浅的探析,并介绍了德国政府机构在绿色医院建筑节能方面的政策及资金支持,以及研究机构和能源管理公司的技术产业支持等内容,以供我国的医院建筑设计同行参考。 相似文献
46.
Combining environmental with employment objectives, ecological tax reform (ETR) envisages a double dividend. While research has mainly focused on the socio-economic and environmental impacts of ETR, there is less literature on the social responses. This paper gives an overview and history of German ETR as well as investigating the understanding of perceptions and attitudes towards ETR of those being “subject to tax”. The research is based on qualitative social research methods. As with the other PETRAS papers, interviews were conducted with policy-makers and business leaders and focus groups were formed with lay persons. The results show that responses of policy-makers and business leaders are modest. Although some criticisms about the specific design of the German ETR remain, complaints towards ETR are settled. Attitudes appear influenced by more fundamental convictions such as economic interest or altruistic views. In contrast, ETR appears to politicise common people. Attitudes are influenced by the overall comprehension of the ETR concept, the expected impacts, perceived information deficits, as well as a general distrust in politics. Our data show that the linking of environmental and employment objectives is not understood and not welcomed. In order to increase social acceptance, the paper discusses refocusing ETR on environmental objectives, modestly increasing the share of ETR revenue spent for environmental purposes, removing inconsistencies in the ETR design, and improving information policy. 相似文献
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The enthusiasm for the use of so-called native plants and the rejection of so-called exotic plants in 20th-century garden and landscape design is explored. The underlying ideas and ideology are discussed using examples in Germany, particularly from the time of National Socialism, and the United States. 相似文献
49.
Discusses the nature of current psychology research in East Germany, including the work of Fischel (neurophysiology, animal behavior and genetics), W. Traxel ("An Empirical System of the Qualities of Feeling"), Vorweg and Vorweg (stereotyped attitudes), Zukowski ("Observations of Sea-Elephants in Captivity,"), Dathe (use of objects as tools by brown bears), and Grimm (bird population in Berlin). It is suggested that psychology in East Germany is a strange mixture of Gestalt principles and environmentalism, Marxist principles worked into the ontogenesis of behavior (as in a paper by G. Clauss), and is far removed from its innovator, Wilhelm Wundt. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
50.
Mingtao Shi 《信息通信技术》2009,3(3):13-18
The German Postal Reform I in 1989 introduced competition in the mobile cellular market. German cellular operators, DeTeMobil, Mannesmann, E-Plus and VIAG Interkom, built D1-, D2-, E1-and E2-Netze based on GSM standards made in Europe. China Unicom was created in 1994 and China Telecom was separated from MPT in 1995. China Telecom and China Unicom competed in a duopoly from the mid-1990s onwards and the cellular services provided by them also rely on GSM standards. China Telecom additionally deployed XLT technology (PHS) from the late 1990s onwards. While DeTeMobil and Mannesmann conquered approximately 80%-90% of the market throughout the 1990s and were the two dominant market players in Germany, China's cellular market was mainly controlled by China Mobile. In Germany, prices related to cellular technology continued the downwards trend as a major result of the process of deregulation, liberalisation and competition. In China, price wars had led to significant price reductions in the cellular market. Although network operators in both countries strived to deliver differentiated cellular services, the two national markets in the 1990s were visibly shaped by product homogeneity. 相似文献