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期刊论文 2

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2008 2

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Nano thermo-hydrodynamics method for investigating cell membrane fluidity

YANG Yang, LIU Jing

《能源前沿（英文）》 2008年第2卷第2期页码 121-128 doi: 10.1007/s11708-008-0033-2

摘要： As a barrier to compartmentalize cells, membranes form the interface between a cell and its surroundings. The essential function of a membrane is to maintain a relatively stable environment in the cell, exchange substances selectively and transfer energy and information continually from the outside. It is intriguing that above the phase transition temperature, the membrane lipid molecule will have three modes–lateral diffusion, rotational movement and flip-flop activity. These thermodynamic processes are vital to cell existence, growth, division, differentiation and are also responsible for hundreds of thousands of phenomena in life. Previously, species transport across the membrane was interpreted mainly from a phenomenological view using a lumped system model. Therefore, detailed flow processes occurred in the membrane domain and clues related to life mechanism were not sufficiently tackled. Such important issues can be clarified by modeling nano scale thermal hydrodynamics over the gap space of a cell membrane. Previously observed complex membrane behaviors will be shown in this paper and explained by the thermally induced fluidic convections inside the membrane. A correlation between nano scale hydrodynamics, non-equilibrium thermodynamics and cell membrane activities is set up. The disclosed mechanisms are expected to provide a new viewpoint on the interaction between intracellular and extracellular processes through the membrane.

关键词： responsible phenomenological phenomena modes–lateral diffusion differentiation

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Investigations concerning seismic response control of self-anchored suspension bridge with MR dampers

YANG Menggang, HU Jianhua

《结构与土木工程前沿（英文）》 2008年第2卷第1期页码 43-48 doi: 10.1007/s11709-008-0011-0

摘要： To mitigate the seismic response of self-anchored suspension bridges, equations of motion governing the coupled system of bridge- magneto-rheological (MR) dampers subject to seismic excitation are formulated by employing the phenomenological model of MR dampers. A corresponding computer program is developed and employed for studying the seismic response control of a self-anchored suspension bridge with a main span of 350 m. The effect of variable current and number of dampers on seismic response control is investigated. The numerical results indicate the longitudinal displacement of the tower top and bridge girder decrease with the increase in input current and number of MR dampers attached longitudinally at the tower-girder connections, and the internal forces of the tower are effectively attenuated as well. It appears that small electronic current (0.5 A in this study) may sufficiently attenuate the seismic responses for practical engineering applications.

关键词： longitudinal displacement corresponding computer excitation phenomenological self-anchored suspension