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81.
Vincenzo Liso Anders Christian OlesenMads Pagh Nielsen Søren Knudsen Kær 《Energy》2011,36(7):4216-4226
The aim of this research work is to describe in qualitative and quantitative form the performance of a micro Combined Heat and Power system for residential application based on Solid Oxide Fuel Cell fueled by natural gas with two different types of pre-reforming systems, namely Steam Reforming and Partial Oxidation and recirculation of anode and cathode gas.The comparative analysis among the different configurations will lead us to conclude that maximum efficiency is achieved when cathode and anode gas recirculation are used along with steam methane reforming. Further Steam Methane Reforming process produces a higher electrical system efficiency compared to Partial oxidation reforming process.Efficiency is affected when running the system in part load mode mainly due to heat loss, additional natural gas supplied to the burner to satisfy the required heat demand inside the system, and ejector efficiency drop in the recirculation system. Due to high temperature of operation heat loss strongly affects the system efficiency especially at part load operation. 相似文献
82.
David M. Schultz 《Scientometrics》2011,86(2):251-259
83.
Nanotechnology is an emerging field of science with the potential to generate new and enhance existing products and transform
the production process. US patent data is used to track the emergence of nanotechnologies since 1978. The nanotechnologies
that have undergone the most development are identified using patent citation data and co-citation patterns of patents are
examined to define clusters of related nanotechnologies. The potential for economic impact of the emerging nanotechnologies
is assessed using a generality index. 相似文献
84.
本文针对昆明的发展特征及面临的挑战,引入了一种全覆盖的综合规划方法来从整体上协调空间的各种职能及保护自然潜力.对大昆明区采用基于GIS的区域模型模拟了这些政策和方法的潜在影响力.结果显示,污染减少、土地利用成本和基础设施的建设成本降低,同时城市的竞争力提高. 相似文献
85.
86.
The corrosion and passivation behaviour of bulk polycrystalline martensite Ni50Mn30Ga20 and austenite Ni48Mn30Ga22 alloys was compared in electrolytes with different pH values. Linear anodic and cyclic potentiodynamic polarisation methods and anodic current transient measurements have been conducted for the alloys and their constituents to analyze free corrosion, anodic dissolution and passive layer formation processes. Electrochemically treated alloy surfaces were characterized with scanning electron microscopy (SEM) and angle-resolved x-ray photoelectron spectroscopy (XPS). The electrochemical response of both alloys is in principal similar and is dominated by the Ni oxidation. In acidic solutions (pH 0.5 and 5) a slightly higher reactivity is detectable for the martensitic alloy which is mainly attributed to enhanced dissolution processes at the multiple twin boundaries. In weakly acidic to strongly alkaline solutions (pH 5-11) both alloys exhibit a low corrosion rate and a stable anodic passivity. While air-formed films comprise NiOOH, Ga2O3 and MnO2, passive films formed in near neutral media (pH 5-8.4) are composed of Ni(OH)2, NiOOH and Ga2O3 in the outer region and of NiO, MnO2 and MnO in the metal-near region. 相似文献
87.
After about a 30-year hiatus of construction in the US but not in all involved countries, the designs for an improved water-cooled nuclear reactor will hopefully be developed by a consortium of nuclear reactor builders and users under an agreement with the US Department of Energy (DOE) and review by the Nuclear Regulatory Commission (NRC). The construction of high-temperature, helium-cooled pebble-bed or prismatic reactors may herald the entry of new, safer, and less costly types of reactors to replace the water-cooled reactors of the past and current types. Nuclear breeder reactors hold the promise of limitless energy supplies without the use of fossil fuels or renewables at acceptable costs but this development program has been stalled periodically, especially in the US, when abundant low-cost uranium sources were added to the supply side. 相似文献
88.
Ackerman Brian P.; D'Eramo Kristen Schoff; Umylny Lina; Schultz David; Izard Carroll E. 《Canadian Metallurgical Quarterly》2001,15(2):288
This study examined the relations among family structure, caregiver relationship history, aspects of environmental adversity, and teacher reports about the externalizing behaviors of 6- and 7-year-old children from economically disadvantaged families. Family structure contrasted intact families, stepfamilies, single-parent families, and cohabiting families. Problem behaviors were more frequent for children from unmarried families than from married families and were more frequent for boys than for girls from cohabiting families. Relationship history reduced the effects for family structure. Children's adjustment varied with both the current status and past stability of caregiver intimate relationships for disadvantaged families. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
89.
The present study aims at investigating the absorption behaviour of acetylated (AFBPI) and non-acetylated (FBPI) faba bean protein isolate at a sunflower oil-water interface in dependence on different environmental conditions (protein concentration, pectin addition). 相似文献
90.
A FORTRAN program is presented which generates a statistical model of broadscale spatially coherent data, and from that model identifies and removes outlying data values. The algorithm also interpolates missing data values by making use of this model, as well as the assumption of broadscale coherence. Examples of the application of this technique to geomagnetic data are presented. A significant improvement in the statistical efficiency and consistency of subsequent estimators is seen to obtain from preprocessing data with this method. 相似文献