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61.
Detecting cooperative partners in situations that have financial stakes is crucial to successful social exchange. The authors tested whether humans are sensitive to subtle facial dynamics of counterparts when deciding whether to trust and cooperate. Participants played a 2-person trust game before which the facial dynamics of the other player were manipulated using brief (  相似文献   
62.
典型的压电传感器包含一片PZT-5A陶瓷材料的圆盘,在其表面有金属化电极.把导电环氧树脂涂到电极上,就可把外部导线连到传感器.绝缘粘合剂把组件连到待测结构,并把传感器和接地参考电位隔离开.圆盘面朝预期加速方向.  相似文献   
63.
The present view of medical environments, where isolated networks are used for IT and medical applications, is changing toward an integrated heterogeneous network scenario that can support a wide range of applications. WPAN and WLAN technologies play a fundamental role in enabling such integrated environment that is expected to support both medical and nonmedical applications. The ultimate goal is to exploit WPAN and WLAN technologies, as well as other wireless networks, such as 3G cellular systems and satellite networks, to support highly efficient medical care delivery, anytime and anywhere. However, the life-critical nature of some medical applications imposes additional challenges that have not been considered in nonmedical scenarios. This article discusses some future scenarios where WLAN and WPAN technologies can be used to provide an integrated and ubiquitous network in medical environments, and identifies the main issues to be addressed in order to meet the QoS requirements of different medical applications when operating in integrated environment  相似文献   
64.
在追求减轻重量,降低系统成本的长期过程中,设备制造商正逐步使用镍金属氢化物电池和锂离子电池来替代NiCd电池和碱性电池.不过,具体使用哪种电池主要是由其充电状况所决定的,而充电状况又是由它们的构成和电化学性质决定的.  相似文献   
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Fluid flow through lances with constant and variable pitch swirled inserts   总被引:1,自引:0,他引:1  
Sirosmelt-type gas injection systems for submerged combustion in metallurgical baths use tubular lances with single or multistart-type helical vane swirlers in the annular region. These inserts not only promote heat transfer from the tube wall to the gas flowing through the tube but also increase pressure drop across the lance. The total pressure loss across such inserts is due to entrance effects and fully developed flow losses. These losses can be quite substantial depending upon the gas flow rate and configuration of inserts. In this paper, a comparison has been made between fixed and variable pitch inserts as far as pressure drop is concerned. A simple flow model has been proposed to describe the flow characteristics of both types of insert. An understanding of these flow characteristics forms a basis for improved lance designs. formerly Research Fellow, G.K. Williams Centre for Extractive Metallurgy, Department of Chemical Engineering, University of Melbourne, Victoria 3052, Australia  相似文献   
69.
Most renewable energy sources depend to some extent on use of other, non-renewable sources. In this study we explore use of diesel fuel in producing and transporting woody biomass in the state of New Hampshire, USA. We use two methods to estimate the diesel fuel used in woody biomass production: 1) a calculation based on case studies of diesel consumption in different parts of the wood chip supply chain, and 2) to support extrapolating those results to a regional system, an econometric study of the variation of wood-chip prices with respect to diesel fuel prices. The econometric study relies on an assumption of fixed demand, then assesses variables impacting supply, with a focus on how the price of diesel fuel affects price of biomass supplied. The two methods yield similar results. The econometric study, representing overall regional practices, suggests that a $1.00 per liter increase in diesel fuel price is associated with a $5.59 per Mg increase in the price of wood chips. On an energy basis, the diesel fuel used directly in wood chip production and transportation appears to account for less than 2% of the potential energy in the wood chips. Thus, the dependence of woody biomass energy production on diesel fuel does not appear to be extreme.  相似文献   
70.
The distribution of cadmium-(Cd)-binding components from five flaxseed cultivars grown at three locations in southern Manitoba was investigated to examine genotypic and environmental effects. Three protein fractions with different electrostatic properties, eluting at 0.10, 0.25 and 0.50 M NaCl by ion-exchange chromatography DEAE-Sephacel, represented 12%, 66% and 7% of the bound (extracted) protein, respectively, while 15% of the protein remained unbound. Cadmium and other divalent metal (zinc, copper and calcium) contents of protein fractions were strongly influenced by location. Cultivar differences in protein and cadmium contents of the protein fractions were highly significant. Cadmium and zinc accumulated similarly in the 0.10 and 0.25 M protein fractions at 51% and 40–43%, respectively. Transfer of copper occurred prominently in the 0.50 M fraction while most of the calcium (55%) remained unbound. The distribution of cadmium, zinc, copper and calcium in fractions of flaxseed proteins was strongly influenced by cultivar and location, indicating differences in their accumulation, migration and transfer.  相似文献   
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