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排序方式: 共有551条查询结果,搜索用时 40 毫秒
61.
Evan F. Koenig 《Energy》1981,6(5):457-470
We examine three alternative methods by which electric utilities might take advantage of distributed thermal energy storage to smooth out their load profiles. These three methods are: (1) time-specific rates, (2) time-invariant rates with subsidized storage, and (3) direct load controls with no subsidies to storage. The optimal form of each of these policies is determined and relations indicating the relative desirability of each are developed. 相似文献
62.
Computer simulation of structure and properties of crosslinked polymers: application to epoxy resins 总被引:1,自引:0,他引:1
In this work, a methodology has been developed for construction of atomistic models of crosslinked polymer networks. The methodology has been applied to low molecular weight water soluble epoxy resins crosslinked with different curing agents that are being considered for use as a primer coating on steel. The simulations allowed the crosslink density and the amount of free crosslinking sites in the coatings to be predicted. Shrinkage of the resin upon curing was reproduced by the simulation. In addition, the barrier properties of the model coatings were estimated. The interface between an inorganic substrate and cured epoxy resin has been constructed and the strength and molecular mechanisms of adhesion have been revealed. The developed methodology has a potential to significantly impact on the design and development of new coatings with improved barrier and adhesion properties. 相似文献
63.
Previous studies show that if acoustic startle stimuli are presented in pairs, then the reaction to the 2nd stimulus (S2) is reduced, with the size of the refractory decrement determined by the interstimulus interval and the relative intensity of the 1st stimulus (S1). If a neutral stimulus (p) is presented just prior to S1, then the reaction to S1 is similarly inhibited, revealing the phenomenon of prestimulus inhibition. In 2 experiments with male albino Holtzman rats (N = 24) it was found that suppression of the reflex to S2 by S1 was unaffected by prestimulus inhibition of S1 (i.e., reflex amplitudes associated with S2 were identical in pS1-S2 series and S1-S2 series). In contrast, a reduction in the intensity of S1 relative to S2 did reduce the effect of S1 on S2. These data indicate that prestimulus inhibition of the reflex to S1 does not result because the preliminary stimulus attenuates the sensory impact of S1. The inhibitory process may be presumed to have a central locus. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
64.
Evan M. Oliver 《Journal of the American Ceramic Society》1948,31(5):128-132
An instrument commonly employed to measure the viscosity of truly viscous liquids was tested to determine its applicability for evaluating consistencies of enamel slips which are solid suspensions in a water medium. Within wide limits of specific gravity differences and variations in set resulting from electrolyte additions, the Brookfield vis-cosimeter afforded comparable information with the pick-up and slump tests employed as references. 相似文献
65.
Leischow Scott J.; Valente Suzanne N.; Hill Anabel L.; Otte Pamela S.; Aickin Mikel; Holden Timothy; Kligman Evan; Cook Gretchen 《Canadian Metallurgical Quarterly》1997,5(1):54
The effects of using several different nicotine replacement treatments on self-reported withdrawal symptoms and side effects during 2-day periods of smoking cessation, with 5 days of ad lib smoking between cessation days, were evaluated. Participants (N ?=?18) experienced the following conditions: nicotine gum, 24-hr patch, 16-hr patch, 24-hr patch plus gum, double 24-hr patch, and no nicotine replacement. The present study found morning urge to smoke was greater during the 16-hr than during the 24-hr patch condition. Double-patch use resulted in significantly greater insomnia than the smoking baseline and 16-hr patch conditions. The no medication and gum alone conditions resulted in similar withdrawal symptoms, and both tended to result in greater reported withdrawal symptoms than the smoking baseline condition. There were no significant withdrawal symptom differences between the 24-hr, patch-gum, and double-patch conditions. The 24-hr and double-patch conditions were preferred by two thirds of the participants (6 each). (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
66.
Nasim Mia Kuljeet Singh James Polson Luciano Lisi Evan Willemsen Yulin Hu 《加拿大化工杂志》2024,102(2):585-606
Hydrogen (H2) is a clean energy carrier widely used in oil refineries, fertilizers, chemicals, and steel manufacturing. Presently, the majority of H2 is produced from either steam methane reforming of natural gas or coal gasification; however, these technologies result in a massive amount of CO2 emission. Alternatively, the use of photocatalysts for producing H2 via water splitting is an eco-friendly and sustainable approach, among which the selection of highly efficient, stable, and cheap photocatalysts is the key. In this review, Znln2S4-based photocatalysts are thoroughly described in terms of the fundamentals and thermodynamics of water splitting, fabrication methods, and different heterostructure photocatalytic systems. After this, recent developments in the large-scale implementation of photocatalytic reactors are discussed. Finally, a summary of future research directions and major conclusions is provided. With proper modification, such as heterojunction systems and the selection of proper fabrication methods, Znln2S4-based photocatalysts could be superior materials for water splitting. In short, this review article could offer meaningful and useful insights and guidance for the development of Znln2S4-based photocatalysts in water splitting for producing H2 under visible light. 相似文献
67.
What can we learn from the spatial logic of collections of trees in the rainforest? Evan Greenberg of the EmTech programme at the Architectural Association (AA) School of Architecture in London and George Jeronimidis of the Centre for Biomimetics at the University of Reading combine forces to analyse the rainforest's morphology and its potential as an urban model. They suggest how the sectional height differentiation of trees could present a new way of thinking about urban organisation, accommodating varied microclimates, programmes and the city's infrastructural flows. 相似文献
68.
69.
Evan J. Telford Avalon H. Dismukes Kihong Lee Minghao Cheng Andrew Wieteska Amymarie K. Bartholomew Yu-Sheng Chen Xiaodong Xu Abhay N. Pasupathy Xiaoyang Zhu Cory R. Dean Xavier Roy 《Advanced materials (Deerfield Beach, Fla.)》2020,32(37):2003240
The recent discovery of magnetism within the family of exfoliatable van der Waals (vdW) compounds has attracted considerable interest in these materials for both fundamental research and technological applications. However, current vdW magnets are limited by their extreme sensitivity to air, low ordering temperatures, and poor charge transport properties. Here the magnetic and electronic properties of CrSBr are reported, an air-stable vdW antiferromagnetic semiconductor that readily cleaves perpendicular to the stacking axis. Below its Néel temperature, TN = 132 ± 1 K, CrSBr adopts an A-type antiferromagnetic structure with each individual layer ferromagnetically ordered internally and the layers coupled antiferromagnetically along the stacking direction. Scanning tunneling spectroscopy and photoluminescence (PL) reveal that the electronic gap is ΔE = 1.5 ± 0.2 eV with a corresponding PL peak centered at 1.25 ± 0.07 eV. Using magnetotransport measurements, strong coupling between magnetic order and transport properties in CrSBr is demonstrated, leading to a large negative magnetoresistance response that is unique among vdW materials. These findings establish CrSBr as a promising material platform for increasing the applicability of vdW magnets to the field of spin-based electronics. 相似文献
70.
Evan C. Schwind Gregory E. Hilmas William G. Fahrenholtz 《Journal of the American Ceramic Society》2020,103(5):2986-2990
Thermal and elastic properties were measured for ceramics that contained as much as 96 wt% zeta phase tantalum carbide (ζ-Ta4C3−x). The ceramics were produced from tantalum hydride that was milled to reduce particle size and then blended with carbon. Powders were reaction hot-pressed at 1800°C for 2 hours under a flowing He environment, which resulted in ζ-Ta4C3−x that was about 99% dense. The main secondary phases present in the reacted ceramic were TaC and Ta2O5. ζ-Ta4C3−x had a thermal conductivity of 9.6 W/m·K and an electrical resistivity of 160 ± 4.2 μΩ-cm, which are lower and higher than those of TaC, respectively. The Young's modulus was 379 ± 5 GPa and the hardness was 5.1 ± 0.7 GPa, which are also both lower than TaC. This study is the first to report the thermal properties and elastic moduli of high-purity ζ-Ta4C3−x. 相似文献