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101.
The goal of this paper is to examine the long-run elasticities of the impacts of energy consumption on GDP and GDP on energy consumption. The energy consumption–GDP relationship is amongst the most popular relationships examined in the energy economics literature. The bulk of the extant literature has assumed a positive relationship between energy consumption and real GDP. Our analysis shows that in only around 60% of the countries considered the relationship is positive. 相似文献
102.
Carbon nanotube papers (CNT papers, also referred to as “buckypapers”) prepared from chemically functionalized single-walled CNTs are being investigated for their mechanical tensile properties. While the Young’s moduli are unaffected by the functionalization with diazonium salts of aniline or aromatic mono- and bis-amides tensile strengths of CNT papers are found to increase with a growing degree of functionalization, and more pronounced with a growing number of amide groups capable of hydrogen bonding. The importance of hydrogen bonding becomes evident after its inhibition through N-methylation of the amide groups, resulting in a distinct reduction of strength values. Scanning electron micrography indicates that a high degree of functionalization or a high number of amide group results in the formation of domains with aligned CNTs. 相似文献
103.
Stephan van Reenen Piotr Matyba Andrzej Dzwilewski René A. J. Janssen Ludvig Edman Martijn Kemerink 《Advanced functional materials》2011,21(10):1795-1802
Incorporation of ions in the active layer of organic semiconductor devices may lead to attractive device properties like enhanced injection and improved carrier transport. In this paper, we investigate the effect of the salt concentration on the operation of light‐emitting electrochemical cells, using experiments and numerical calculations. The current density and light emission are shown to increase linearly with increasing ion concentration over a wide range of concentrations. The increasing current is accompanied by an ion redistribution, leading to a narrowing of the recombination zone. Hence, in absence of detrimental side reactions and doping‐related luminescence quenching, the ion concentration should be as high as possible. 相似文献
104.
Stephan Renner 《Datenschutz und Datensicherheit - DuD》2011,35(8):524-529
In ?sterreich wurden Ende 2010 die rechtlichen Grundlagen für die Einführung von elektronischen Z?hlern (Smart Meters) geschaffen.
Datenschutz und der Schutz der Privatsph?re spielen dabei eine bedeutende Rolle. Vor der Einführung intelligenter Messger?te
ist jedenfalls zu definieren, zu welchen Zwecken Daten notwendig sind. 相似文献
105.
106.
Yvonne Serfert Stephan Drusch Benjamin Schmidt-Hansberg Matthias Kind Karin Schwarz 《Journal of food engineering》2009,95(3):386-392
Aim of the present study was to investigate the impact of the emulsifying carrier matrix constituent, n-octenylsuccinate-derivatised (OSA)-starch, and process conditions on physical characteristics and oxidative stability of microencapsulated fish oil. Furthermore, the effect of the drying medium, i.e. air or nitrogen, on lipid oxidation during spray-drying and subsequent storage was investigated. Particle characteristics and lipid oxidation of microencapsulated fish oil were both influenced by the type of OSA-starch and the drying conditions. The highest oxidative stability was observed for fish oil microencapsulated in OSA-starch with the lowest average molecular weight and glucose syrup spray-dried at a moderate temperature setting. Particle characteristics of the microcapsules were not attributable for differences in lipid oxidation during storage. In spray-dried carrier matrix particles, the particle size increased with increasing average molecular weight of the OSA-starch and was attributed to an increase in air inclusion. Thus differences in lipid oxidation of the microencapsulated fish oil were attributed to differences in air inclusion as affected by the type of OSA-starch. In terms of spray-drying under inert conditions and in the presence of air, lipid oxidation of microencapsulated fish oil was rather attributed to oxygen availability in the feed emulsion than in the drying gas. 相似文献
107.
The visual recognition of dynamic scenes was examined. The authors hypothesized that the notion of canonical views, which has received strong empirical support for static objects, also holds for dynamic scenes. In Experiment 1, viewpoints orthogonal to the main axis of movement in the scene were preferred over other viewpoints, whereas viewpoints in line with the main axis were least preferred. Experiment 2 provided no empirical evidence for a recognition advantage of canonical viewpoints when presented during the initial learning phase, but Experiment 3 showed a cognitive advantage for canonical viewpoints if they were presented as test stimuli during the recognition test. Overall, the findings suggest that on a phenomenological level, viewers are consciously aware of such viewpoints, and, on a cognitive level, viewers benefit from canonical viewpoints in terms of recognition accuracy. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
108.
109.
It is a truism that today’s simulations of mobile wireless networks are not realistic. In realistic simulations of urban networks, the mobility of vehicles and pedestrians is greatly influenced by the environment (e.g., the location of buildings) as well as by interaction with other nodes. For example, on a congested street or sidewalk, nodes cannot travel at their desired speed. Furthermore, the location of streets, sidewalks, hallways, etc. restricts the position of nodes, and traffic lights impact the flow of nodes. And finally, people do not wander the simulated region at random, rather, their mobility depends on whether the person is at work, at lunch, etc. In this paper, realistic simulation of mobility for urban wireless networks is addressed. In contrast to most other mobility modeling efforts, most of the aspects of the presented mobility model and model parameters are derived from surveys from urban planning and traffic engineering research. The mobility model discussed here is part of the UDel Models, a suite of tools for realistic simulation of urban wireless networks. The UDel Models simulation tools are available online. 相似文献
110.
R. Srikar T. Gambaryan-Roisman C. Steffes P. Stephan C. Tropea A.L. Yarin 《International Journal of Heat and Mass Transfer》2009,52(25-26):5814-5826
A novel enhancement of drop and spray cooling for microelectronic and radiological elements and server rooms requiring extremely high heat fluxes is proposed. The key idea of the method is to cover the heat transfer surfaces with electrospun non-woven polymer nanofiber mats. The mats are permeable for water drops. The enhanced efficiency of drop cooling in the presence of nanofiber mats observed experimentally results from full elimination of receding and bouncing of the drops, characteristic of the current spray cooling technology. Therefore, the drops evaporate completely, and the large cooling potential associated with the latent heat of water evaporation is more fully exploited. This is paradoxical: the best cooling can be provided by a “fur overcoat”! The proposed cooling method alone may lead to a breakthrough in further miniaturization of microelectronic chips, optical and radiological elements and accelerate the development of a new generation of computers. In order to check the suitability of different materials for the drop and spray cooling applications, the thermal and structural properties of nanofiber mats based on four different polymers have been measured over a wide temperature range. Based on the results of these measurements, the most suitable materials have been chosen. 相似文献