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Langmuir films (LFs) of biphenyl and anthracene derivatives on the surface of liquid mercury were studied by surface-specific X-ray and surface tension measurements. Phases of lying-down, side-lying and standing-up molecules were found, some of which exhibit long-range lateral order. The molecular symmetry and the position and nature of the side-, end-, and headgroups are shown to dominate the structural evolution of the LFs with surface coverage.  相似文献   
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Abstract

In this paper, we identify processes associated with “Tactical IT-Business Alignment”, illustrate four types of alignment states resulting from “strategic” and “tactical” alignment levels, and propose alignment-related managerial actions appropriate for each type. Our results are based on about 45 hours of interviews with about 30 senior, middle and junior managers from IS and other functions, and from company records, in an investigation of four organizations.  相似文献   
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The Temburong Bridge Project is a 30 km long dual two‐lane highway crossing over the Brunei Bay. It will connect the relatively isolated Brunei district of Temburong to the other three Brunei districts. The main objective of the project is to stimulate economic growth in the Temburong region by connecting it to the country's airport and ports. The alignment crosses two navigation channels resulting in the need for two cable stayed bridges – the Brunei Channel Bridge (145 m main span) and the Eastern Channel Bridge (260 m main span). The design of these cable stayed bridges is one of the first applications of the Eurocode to a fully concrete cable stayed bridge. Both cable stayed bridges draw on strong Islamic architectural influences from the region to form a tower shape that is unique and instantly recognisable. Temburong Brücke, Brunei – Entwurf von zwei Schrägkabelbrücken Die Temburong Brücke ist eine 30 km lange Verbindung über die Brunei Bucht mit zwei Richtungsfahrbahnen mit je zwei Fahrstreifen. Sie wird den relativ isolierten Distrikt Temburong mit den anderen drei Distrikten Bruneis verbinden. Hauptanliegen des Projekts ist die Stimulierung von ökonomischem Wachstum in der Temburong Region, indem sie an den Flughafen und Seehafen des Landes angebunden wird. Die Trassierung erfordert die Überquerung zweier Schiffahrtsrouten. Dies wird mit der Anordnung zweier Schrägkabelbrücken ermöglicht, der Brunei Channel Brücke (145 m Hauptspannweite) und der Eastern Channel Brücke (260 m Hauptspannweite). Die Bemessung der beiden Brücken stellt eine der ersten Anwendungen des Eurocode auf Schrägkabelbrücken mit Betonüberbau dar. Optisch sind die beiden Brücken geprägt von der islamischen Architektur der Umgebung, die Pylonform ist ein besonderes Erkennungsmerkmal der Brücken.  相似文献   
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A simple model is developed for the estimation of viscosity of hydrocarbon liquids considering that drag on molecular motion due to thermal energy is balanced by intermolecular attractions. The model equation is validated with National Institute of Standards and Technology data on hydrocarbon liquids (C3-C10 and C12) considering the effect of molecular shape on drag force. The molecular shape is correlated well with molecular weight of hydrocarbon liquids. The accuracy of the proposed model equation is compared with the correlation. The result showed that the proposed model is more accurate. The proposed model equation predicts the viscosity over a wide range of temperature for C3-C25 with overall absolute average deviation of 5.13%.  相似文献   
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The fracture surface energy, γ, of ThO2 was measured between room temperature and 400°C using the Hertzian indentation technique with cold or preheated steel and alumina indentors. The value of γdecreased strongly with temperature with a suggested saturation at 350°C. This may indicate the change from an unrelaxed fracture surface to a relaxed surface at temperatures where oxygen becomes mobile. The result obtained at 400°C is γ=1.4 J m−2.  相似文献   
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In this paper, we propose high-rate space–time coding for cooperative wireless networks to reduce the overall delay incurred in relaying signals to multiple receivers. The relay structure is optimized in order to achieve maximum SNR at the receiver nodes. The proposed scheme provides a significant reduction in the delay required for the relaying and transmission of the signals to the multiple receivers with a minute loss in performance. We have also shown by simulation that this loss in the performance could be recovered by selecting more number of relays. We propose two relaying strategies for high-rate space–time codes, which are very useful in providing high data-rate in wireless cooperative networks.  相似文献   
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Partial order in crystals is a frequently observed phenomenon in minerals and synthetic materials. The partially ordered structures are characterized by low-dimensional order of the real structure. In the case of 1D structures, the ordered units can be described as rods; 2D structures contain ordered layers. The disorder of the real structures is indicated by prominent diffuse scattering in the diffraction patterns of single crystals. No simple method for the quantitative analysis of the diffuse scattering exists, therefore the determination of essential characteristics of the structures is complicated. However, the determination can be facilitated using a combination of different methods, including electron microscopy, computation and X-ray diffraction.  相似文献   
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