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991.
工业热泵的经济性研究 总被引:4,自引:0,他引:4
在过程集成原理的基础上,分析了各种热泵的技术特性,指出各种形式热泵最适宜的总复合曲线形状,并导出了一个判断工业热泵经济上可行的指标-临界COP,它是输入能量价格与热价之比γ、设备价格与热价之比γ及投资回收期PBP的函数,通过分析各种形式热泵的COP,Cr^-的关系曲线,讨论了γ、PBP,λ对该指标的影响,认为γ对COP的影响最大,PBP次之,λ的影响最小;机械式蒸汽再压缩式热泵及第2类吸收式热泵经 相似文献
992.
993.
Kolsoom Ahmadisoltansaraei Javad Moghaddam 《矿物冶金与材料学报》2014,21(7):726-735
A mechanical activation process was introduced as a facile method for producing nickel oxide nanopowders. The precursor compound Ni(OH)2-NiCO3-4H2O was synthesized by chemical precipitation. The precursor was milled with NaCl diluent. A high-energy ball milling process led to decomposition of the precursor and subsequent dispersal in NaCl media. Nickel oxide nanocrystalline powders were produced by subsequent heat treatment and water washing. Milling rotation speed, milling time, ball-to-powder ratio (BPR), and nickel chlo-ride-to-precursor ratio were introduced as influential parameters on the wavelength of maximum absorption (λmax). The effects of these pa-rameters were investigated by the Taguchi method. The optimum conditions for this study were a milling rotation speed of 150 r/min, a mill-ing time of 20 h, a BPR of 15/1, and a NaCl-to-powder weight ratio (NPR) of 6/1. In these conditions,λmax was predicted to be 292 nm. The structural properties of the samples were determined by field emission scanning electron microscopy, X-ray diffraction, and energy dispersive spectrometry. 相似文献
994.
In micropipette aspiration experiment, increasing mechanical stress applied to cell membrane induced degranulation of mast cell as well as a current that could be inhibited by an inhibitor, which is specific for the transient receptor potential vanilloid (TRPVs) channels. To determine the sensitivity of TRPVs to membrane strain and tension, and to gain new insights into the activation mechanism of TRPVs, finite element models of mast cell and molecular dynamic simulations of human aquaporin-1 are presented. During the finite element simulations, the cell membrane sustained to micropipette aspiration was simulated, and the strain distribution along membrane thickness direction was obtained. Besides, combining the finite element models of osteoblast aspirated into micro- pipette and other compared models, we examined the relationship between cell mechanical stimulations and mechanical attributes and presented a new perspective to determine the cell equivalent elastic modulus. Consid- ering the indetermination of TRPV crystal structure, human aquaporin-1, one kind of the channel membrane proteins, substituting for TRPV, has been studied with molecular dynamic (MD) simulations, under different external lateral tensions which have been obtained in mast cell finite ele- ment simulations, to investigate the mechanical stimulation effects on the membrane channels. The simulations show that human aquaporin-1 undergoes significant conforma- tional change and expands in accordance with lateraltension, which not only confirms the tendency of the pre- vious electrophysiological experiments but also leads us to a better understanding of TRPVs. The multi-scale study combining finite element simulation and MD simulation is a significant breakthrough in the field of mechanical mechanism in cell system. 相似文献
995.
996.
机械模块是AP1000机组核电站系统功能段重要的承载体,其结构复杂,包含物项众多,集成化程度较高。本文介绍了机械模块在现场施工过程中遇到的关于风管和管道保温的问题,为后续核电堆型的模块化设计、制造提供经验。 相似文献
997.
林东Ng3段油藏为高孔高渗曲流河正韵律沉积为主的层状构造、边-底水稠油油藏,属低丰度、低产、浅层稠油油藏。目前存在粘度大,防砂效果差,产能低等问题。本文在分析了该油藏开发特征的基础上,选取了天然能量开采、常规水驱开采、蒸汽吞吐开采等几种开发方式进行了论证,并对水平井开采可行性进行了分析,认为该块适合进行水平井蒸汽吞吐开发。 相似文献
998.
Hui Jiang Shibi Fang 《复旦学报(自然科学版)》2005,44(5):746-747
All solid-state polymer electrolytes for lithium battery was proved to be an attractive direction. Compared with prevenient polymer electrolytes all solid-state polymer electrolytes were superiority in more broad electrochemical window, more stable/low interracial resistance especially when situ-polymerization utilized, excellent mechanical properties and dissepiment free. A lithium secondary battery using all solid-state polymer electrolyte meet the challenge of energy source for both portable electronic devices and electric vehicles (EV) or engine/battery hybrid vehicles (HEV). All solid-state comb-like network polymer electrolytes (CNPE) based on polysiloxane with internal plasticizing chain (IPC) has been designed and synthesized. See Fig. 1. 相似文献
999.
杨俊明 《科技情报开发与经济》2005,15(19):280-281
为保证沥青路面的平整度,介绍了机械摊铺时应采取的操作措施,以及机械碾压方法和接缝处的处理措施. 相似文献
1000.
<正>定向钻施工是指无法以传统方式开挖、推进或作业人员无法进入工作区域时,采用机械方法进行钻掘、排土清渣及方向控制,扩孔后将燃气管道埋入地下的施工方法。 相似文献