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生物医学工程学杂志 2005年第S1期22卷 35-36页

作者： Mian LONG(national microgravity laboratory,{3., chinese Academy of sciences, beijing 100080,china)

Numerical study on onset of oscillatory thermocapillary flow in rectangular liquid pool

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Science china(Technological sciences) 2010年第4期53卷 1069-1076页

作者： HU WenRui,TANG ZeMei & LI Kai Key laboratory of microgravity(national microgravity laboratory),institute of mechanics,chinese Academy of sciences,beijing10090,china 1. Key laboratory of microgravity (national microgravity laboratory) Institute of Mechanics Chinese Academy of Sciences Beijing 10090 China

Thermocapillary flow in a rectangular liquid pool of large Prandtl fluid(Pr=105.6) is numerically studied in *** thermocapillary flow arises when the imposed temperature difference between the sidewalls exceeds a critical *** fluctuations of the oscillatory flow,accompanied by the propagation of the hydrothermal wave from the cold sidewall to the hot one,are much smaller than the time-averaged velocity and temperature *** corresponding disturbance cells arise in the centre of the liquid pool initially,and extend to the whole region with the increasing imposed temperature *** present study reveals the different characteristics of the oscillatory themocapillary flow in the rectangular liquid pool as compared to the cases in other configurations.

关键词： hydrothermal wave bifurcation numerical simulation microgravity

2023.Guideline for the management of hypertension in the elderly population in china

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Journal of Geriatric Cardiology 2024年第6期21卷 589-630页

作者： Hypertension Branch of chinese Geriatrics Society,beijing Hypertension Association,national Clinical Research Center of the Geriatric Diseases Qi HUA Li FAN Zeng-Wu WANG Jing LI 不详 Xuanwu Hospital Capital Medical UniversityBeijingChina chinese PLA General Hospital BeijingChina Fuwai Hospital Chinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina

Preamble Hypertension is one of the most common chronic diseases and the primary risk factor for stroke,myocardial infarction and even cardiovascular *** than half of the elderly population has high blood *** people are a unique group,and strategies for the prevention,diagnosis,evaluation,and treatment of hypertension in elderly individuals differ significantly from those in the general population.

关键词： hypertension prevention diagnosis

Characterization of plastic flow in two Zr-based bulk metallic glasses

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Science china(Technological sciences) 2006年第4期49卷 414-424页

作者： XING Dongmei1,2, ZHANG Taihua1, LI Weihuo3.& WEI Bingchen3.1. State Key laboratory of Nonlinear mechanics (LNM), institute of mechanics, {3. Academy of Sci- ences, beijing 100080, china 2. College of Physics and Electronic Information Science, Tianjin Normal University, Tianjin 3.0074, china 3. national microgravity laboratory, institute of mechanics, {3. Academy of sciences, beijing 100080, china 1. State Key laboratory of Nonlinear mechanics (LNM) Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China 2. College of Physics and Electronic Information Science Tianjin Normal University Tianjin 300074 China 3. national microgravity laboratory Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China

Plastic deformation behaviors of Zr65Al10Ni10Cu15 and Zr52.5Al10Ni10Cu15Be12.5 bulk metallic glasses (BMGs) are studied by using the depth-sensing nanoindentation, microindentation and uniaxial compression. The Be-containing BMG exhibits a signifi- cantly improved overall plastic strain compared with the Be-free alloy during compressive tests. Both BMGs show a loading-rate-dependent serrated flow during nanoindentation measurements, but the Be-containing alloy exhibits a much lower critical loading rate for the disappearance of the serration than the Be-free BMG. The shear band patterns de- veloped during plastic deformation are investigated by microindentation technique, wherein much higher shear band density is found in the Be-containing alloy than in the Be-free alloy, indicating an easier nucleation of shear bands in the former BMG. The dif- ference in the plastic deformation behavior of the two BMGs can be explained by a free volume model.

关键词： Bulk metallic glass, plastic deformation, shear band, nanoindentation.

Competitive Adsorption between Bovine Serum Albumin and Collagen Observed by Atomic Force Microscope

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chinese Chemical Letters 2004年第12期15卷 1465-1468页

作者： Yong YU Pei Qing YING Gang JIN national microgravity Lab,institute of {3.,chinese Academy of sciences, beijing 100080 national microgravity Lab Institute of MechanicsChinese Academy of SciencesBeijing 100080

Atomic force microscopy (AFM) was used to study the competitive adsorption betweenbovine serum albumin (BSA) and type Ⅰ collagen on hydrophilic and hydrophobic silicon wafers.BSA showed a grain shape and the type Ⅰ collagen displayed fibril-like molecules with relativelyhomogeneous height and width, characterized with clear twisting (helical formation). These AFMimages illustrated that quite a lot of type Ⅰ collagen appeared in the adsorption layer on hydrophilicsurface in a competitive adsorption state, but the adsorption of BSA was more preponderant than thatof type Ⅰ collagen on hydrophobic silicon wafer surface. The experiments showed that theinfluence of BSA on type Ⅰ collagen adsorption on hydrophilic surface was less than that onhydrophobic surface.

关键词： Atomic force microscope protein competitive adsorption collagen bovine serum albumin.

Numerical simulation of Richtmyer-Meshkov instability

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Science china Mathematics 2004年第z1期47卷 234-244页

作者： FU Dexun, MA Yanwen, ZHANG Linbo & TIAN BaolinState Key laboratory of Nonlinear mechanics, institute of mechanics, {3. Academy of sciences, beijing 100080, china State Key laboratory of Scientific and Engineering Computing, institute of Computational Mathematics, {3. Academy of sciences, beijing 100080, china 1. State Key laboratory of Nonlinear mechanics Institute of Mechanics Chinese Academy of Sciences 100080 Beijing China2. State Key Laboratory of Scientific and Engineering Computing Institute of Computational Mathematics Chinese Academy of Sciences 100080 Beijing China

The compressible Navier-Stokes equations discretized with a fourth order accurate compact finite difference scheme with group velocity control are used to simulate the Richtmyer-Meshkov (R-M) instability problem produced by cylindrical shock-cylindrical material interface with shock Mach number Ms=1.2 and density ratio 1:20 (interior density/outer density). Effect of shock refraction, reflection, interaction of the reflected shock with the material interface, and effect of initial perturbation modes on R-M instability are investigated numerically. It is noted that the shock refraction is a main physical mechanism of the initial phase changing of the material surface. The multiple interactions of the reflected shock from the origin with the interface and the R-M instability near the material interface are the reason for formation of the spike-bubble structures. Different viscosities lead to different spike-bubble structure characteristics. The vortex pairing phenomenon is found in the initial double mode simulation. The mode interaction is the main factor of small structures production near the interface.

关键词： R-M instability, direct numerical simulation, shock-interface interaction.

Modeling on runoff concentration caused by rainfall on hillslopes and application in Maoping slope

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Progress in Natural Science:Materials International 2006年第10期16卷 1056-1065页

作者： LIU Qingquan and LI Jiachun (institute of mechanics, chinese Academy of {3., beijing 100080, china) [a]chinese Academy of sciences' Institute of Mechanics' Beijing China

Based on the fact that the concentration flowlines of overland flow depend on the surface landform of hillslope, a kinematic wave model was developed for simulating runoff generation and flow concentration caused by rainfall on hillslopes. The model-simulated results agree well with the experimental observations. Applying the model to the practical case of Maoping slope, we obtained the characteristics of runoff generation and infiltration on the slope. Especially, the simulated results adequately reflected the confluent pattern of surface runoff, which offers a scientific foundation for designing the drainage engineering on the Maoping slope.

关键词： complex hillslope rainfall infiltration overland flow runoff concentration Maoping slope.

An optimization approach to the similarity criteria of flows and its application

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Progress in Natural Science:Materials International 2006年第3期16卷 241-247页

作者： ZHOU Jifu and LI Jiachun (institute of mechanics, chinese Academy of {3., beijing 100080, china) [a]institute of mechanics Chinese Academy of Science Beijing China

In the present paper, we propose an optimization approach to investigate the similarity criteria of complex flows. With this approach, we may identify the dominant dimensionless variables governing complex flows by numerical sensitivity analysis. Firstly, we define the sensitivity factor and examine its dependence on the dimensionless variables. Then, we apply this approach to study the similarity criteria of porous media flow in a presumed oil reservoir. The similarity principle obtained from the numerical sensitivity analysis is in agreement with the theoretical law, thus demonstrating the feasibility of the proposed optimization approach. Further explanation is given by analyzing the deviation of pressure distribution in a model from its prototype. In addition, we examine the effects of flow parameter variation on the sensitivity factors and find that the dominant dimensionless variables may change from different sets of parameters.

关键词： similarity optimization sensitivity analysis complex flows model.

Period-doubling bifurcations of the thermocapillary convection in a floating half zone

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Science china(Physics,mechanics & Astronomy) 2010年第9期53卷 1681-1686页

作者： AA Yan,LI Kai,TANG ZeMei,CAO ZhongHua & HU WenRui national microgravity laboratory,{3. of mechanics,chinese Academy of sciences,beijing 100190,china 1. national microgravity laboratory Institute of Mechanics Chinese Academy of Sciences Beijing 100190 China

This study experimentally explored the fine structures of the successive period-doubling bifurcations of the time-dependent thermocapillary convection in a floating half zone of 10 cSt silicone oil with the diameter d0=3.00 mm and the aspect ratio A=l/d0=0.72 in terrestrial *** onset of time-dependent thermocapillary convection predominated in this experimental configuration and its subsequent evolution were experimentally detected through the local temperature *** experimental results revealed a sequence of period-doubling bifurcations of the time-dependent thermocapillary convection,similar in some way to one of the routes to chaos for buoyant natural *** critical frequencies and the corresponding fractal frequencies were extracted through the real-time analysis of the frequency spectra by Fast-Fourier-Transfor-mation(FFT).The projections of the trajectory onto the reconstructed phase-space were also ***,the experimentally predicted Feigenbaum constants were quite close to the theoretical asymptotic value of 4.669 [Feigenbaum M *** Lett A,1979,74:3.5-3.8].

关键词： thermocapillary convection bifurcation transition to turbulence

Scheme construction with numerical flux residual correction (NFRC) and group velocity control (GVC)

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Progress in Natural Science:Materials International 2006年第12期16卷 1252-1259页

作者： MA Yanwen **and FU Dexun(LNM, institute of mechanics, chinese Academy of sciences,{3., china) [a]LNM Institute of Mechanics Chinese Academy of Sciences Beijing China

For simulating multi-scale complex flow fields like turbulent flows, the high order accurate schemes are preferred. In this paper, a scheme construction with numerical flux residual correction (NFRC) is presented. Any order accurate difference approximation can be obtained with the NFRC. To improve the resolution of the shock, the constructed schemes are modified with group velocity control (GVC) and weighted group velocity control (WGVC). The method of scheme construction is simple, and it is used to solve practical problems.

关键词： high order accurate scheme group velocity control high resolution of the shock.