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81.
82.
In the current shift from conventional fossil-fuel-based materials to renewable energy,ecofriendly mate-rials have attracted extensive research interest due to ... 相似文献
83.
Dong Liang Wenqia Wang Yu Cheng 《International journal for numerical methods in engineering》2009,80(3):338-354
In the paper we consider the non‐linear aerosol dynamic equation on time and particle size, which contains the advection process of condensation growth and the process of non‐linear coagulation. We develop an efficient second‐order characteristic finite element method for solving the problem. A high accurate characteristic method is proposed to treat the condensation advection while a second‐order extrapolation along the characteristics is proposed to approximate the non‐linear coagulation. The method has second‐order accuracy in time and the optimal‐order accuracy of finite element spaces in particle size, which improves the first‐order accuracy in time of the classical characteristic method. Numerical experiments show the efficient performance of our method for problems of log‐normal distribution aerosols in both the Euler coordinates and the logarithmic coordinates. Copyright © 2009 John Wiley & Sons, Ltd. 相似文献
84.
异步电动机是将电能转化为机械功的关重设备,在工业和人类生活中有着极为广泛的应用。振动作为电能-机械能转换不可避免的环节,其影响了能量转换的效率以及设备的安全性、可靠性,一般对振动问题的总结与描述从故障诊断的角度进行了分析研究较多,而从振动产生机理及动力学的方面进行论述却很少。综述力求以动力学(激励源)研究为基础,力求搭建异步电机电磁振动系统性的分析途径与方法,以帮助工程技术人员掌握异步电机电磁振动理论的进展并为深入研究提供借鉴。首先介绍了电机中电磁振动的来源,包括机械因素和电磁因素。并介绍电磁振动分析的理论方法。 相似文献
85.
通过对国产纸膜和日本滤纸膜材料的分析研究,研制出NIMTE异相膜,并在空气能量回收装置使用过程中对风压、空气流量、热流方向与热交换效率、回收能量、能效及安全性的关系进行分析,设计出能够更好发挥异相膜使用效果的传热膜机芯,有效提高空气能量回收装置的综合性能。 相似文献
86.
Jin Shu Mao Xiang Hui Wang Kang De Yao Qing Xin Shang Guang Hui Yang 《Journal of Materials Science》2003,38(10):2283-2290
The culture of keratinocytes on flexible membranes has been proposed as a means to simplify, accelerate and improve the efficiency with which proliferating cells are delivered to full thickness or non-healing skin defects. The purpose of this article was to study the ability of chitosan-gelatin manbranes to facilitate the growth of human keratinocytes. The membranes with different chitosan contents were studied. The surface properties of chitosan-gelatin membranes were investigate by SEM, and water contact angle test. The mechanical property of the membranes was tested. Data implied that gelatin could make the membranes more flexible and hydrophilic than chitosan membranes, which may regulate the seeded cells behavior. Loading human keratinocytes on chitosan-gelatin membranes, cells attachment, spread, and growth were investigated by light microscopy, SEM, and MTT test. The results suggested that the adhesion and proliferation of keratinocytes seeded on chitosan-gelatin membranes were same as on tissue culture plate, in which gelatin could modify the interaction between keratinocytes and chitosan membranes. Therefore, chitosan-gelatin membrane is a good candidate for keratinocytes delivery system. 相似文献
87.
Feng Dong Chao Tan Junwen Liu Yanbin Xu Huaxiang Wang 《IEEE transactions on instrumentation and measurement》2006,55(4):1208-1214
A new electrical resistance tomography system has been designed using the single drive electrode method. The bidirectional pulse current is adopted in this system as the exciting current. The model of this new method has been set up in ANSYS and validated by simulation and actual measured data. Based on this model, the influence of medium resistivity and connected resistance as well as the influence of medium distribution on the measured data is studied. The experimental results and the reconstructed images are presented at last to testify to the reliability of the new system and the feasibility of the new method. 相似文献
88.
Artificial Protection Film on Lithium Metal Anode toward Long‐Cycle‐Life Lithium‐Oxygen Batteries
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89.
The mechanical properties of hot rolled strip are the key index of product quality,and the soft sensing of them is an important decision basis for the control a... 相似文献
90.
Shi-Kai Shen Xin-Lei Cui Chuan-Yu Guo Xin Dong Xian-Fa Zhang Xiao-Li Cheng Li-Hua Huo Ying-Ming Xu 《稀有金属(英文版)》2021,(6):1545-1553
Sensing mechanism is still a big problem in the field of gas sensor.In-depth study of the sensing mecha-nism can provide better ideas for the design of sensing ... 相似文献