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Solvent Property Induced Morphological Changes of ABA Amphiphilic Triblock Copolymer Micelles in Dilute Solution: A Self-consistent Field Simulation Study

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Chinese Journal of Polymer Science 2014年第12期32卷 1704-1713页

作者： Juan-juan Fan yuan-yuan han 崔杰 College of Information Technology Jilin Agricultural University State Key Laboratory of Polymer Physics and Chemistry Changchun Institute of Applied Chemistry Chinese Academy of Sciences

The morphological changes of ABA amphiphilic triblock copolymer micelles in dilute solution were systematically studied by tuning the solvent property using self-consistent field simulation. The solvent property was tuned by changing the Flory-Huggins interaction parameters between each type of blocks and solvent, respectively. The simulation results show that by changing the solvent properties, a series of micelle morphologies such as vesicle, cage-like, ring-shaped, rod-like and spherical micelle morphologies can be obtained. Variations of the free energy of the solution system and the surface area of micelles with the Flory-Huggins interaction parameters were calculated to better understand the effect of solvent property on micelle morphologies. In addition, a phase diagram showing the morphological changes of micelles with the Flory-Huggins interaction parameters is provided.

关键词： Solvent property Triblock copolymer Self-consistent field Simulation.

Design and Coupled Thermo-Mechanical Analysis of Silicon Carbide Primary Mirror Assembly

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Chinese Journal of Aeronautics 2006年第B12期19卷 62-65页

作者： han yuan-yuan ZhanG Yu-min han Jie-cai Center for Composite Materials Harbin Institute of Technology Harbin 150080 China

Based on the principle that the thermal expansion coefficient of the support structure should match that of the mirror, three schemes of primary mirror assembly were designed. Of them, the first is fused silica mirror plus 4J32 flexible support plus ZTC4 support back plate, the second K9 mirror plus 4J45 flexible support plus ZTC4 support back plate, and the third SiC mirror plus SiC rigid support back plate. A coupled thermo-mechanical analysis of the three primary mirror assemblies was made with finite element method. The results show that the SiC assembly is the best of all schemes in terms of their combination properties due to its elimination of the thermal expansion mismatch between the materials. The analytical results on the cryogenic property of the SiC primary mirror assembly show a higher surface finish of the SiC mirror even under the cryogenic condition.

关键词： silicon carbide primary mirror assembly design coupled thermo-mechanical analysis

Intelligent Modularized Reconfigurable Mechanisms for Robots:Development and Experiment

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Chinese Journal of Mechanical Engineering 2020年第5期33卷 88-100页

作者： Wenfu Xu Liang han Xin Wang han yuan Bin Liang School of Mechanical Engineering and Automation Harbin Institute of TechnologyShenzhen 518055China Department of Automation Tsinghua UniversityBeijing 100084China

With the development of intelligent flexible manufacturing,traditional industrial manipulators with a single configuration are difficult to meet a variety of *** robots have developed rapidly which could change their configurations and end effectors for different *** reconfigurable connecting mechanism(RCM)is a core component of reconfigurable *** this paper,two types of intelligent modularized RCMs with light weight,high payload,and large pose(position and attitude)error tolerance are *** is driven by shape memory alloy(SMA)and recovery *** is locked by steel balls and *** other is driven by electromagnetic coil and locked by permanent magnet and *** locking principle,mechanical system and control system of the two RCMs are detailed *** of them meet the requirements of high precision and high payload in the industrial ***,the developed RCMs are respectively integrated to a practical robot and *** experiment results verified the performance of the two RCMs.

关键词： Reconfigurable connecting mechanisms Shape memory alloy Electromagnetic Reconfigurable manipulator

Estimation of solid concentration in solid-liquid two-phase flow in horizontal pipeline using inverse-problem approach

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Particuology 2022年第3期20卷 1-13页

作者： Ji Zhang han yuan Ning Mei Zhe Yan Marine Engineering College of EngineeringOcean University of ChinaQingdao 266100China Offshore Engineering Department of CivilEnvironmental and MiningUniversity of Western Australia35 Stirling HwyCrawleyWA 6009Australia Power Engineering and Engineering Thermophysics School of Mechanical EngineeringShanghai Jiao Tong UniversityShanghai 200240China

In this study,an inverse-problem method was applied to estimate the solid concentration in a solid-liquid two-phase *** algebraic slip mixture model was introduced to solve the forward problem of solid-liquid convective heat *** time-average conservation equations of mass,momentum,energy,as well as the volume fraction equation were computed in a computational fluid dynamics(CFD)*** solid concentration in the CFD model was controlled using an external program that included the inversion iteration,and an optimal estimation was performed via experimental *** using a fly-ash-water mixture and sand-water mixture with different solid concentrations in a horizontal pipeline were conducted to verify the accuracy of the inverse-problem *** estimated results were rectified using a method based on the relationship between the estimated results and estimation error;consequently,the accuracy of the corrected inversion results improved *** a verification through experiments,the inverse-problem method was concluded to be feasible for predicting the solid concentration,as the estimation error of the corrected results was within 7%for all experimental samples for a solid concentration of less than 50%.The inverse-problem method is expected to provide accurate predictions of the solid concentration in solid-liquid two-phase flow systems.

关键词： Solid-liquid two-phase flow Solid concentration estimation Coupling calculation Inverse heat transfer problem Algebraic slip mixture model

Analysis of the motion of small-scale ellipsoidal particles in a horizontal laminar flow field

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Particuology 2018年第5期16卷 44-51页

作者： Lin Yang Ji Zhang han yuan Ning Mei Marine Engineering College of Engineering Ocean University of ChinaQingdao 266100China

A particle movement model for a horizontal laminar flow field was established in this study,using a modified Basset-Boussinesq-Oseen equation for multiphase fluid dynamics,The motion of ellipsoidal and spherical particles in this flow field was compared to determine the differences in entrainment of ellipsoidal versus spherical *** theoretical results indicate that ellipsoidal particles move more rapidly and smoothly within the fluid than spherical particles under the same ***,this feature is enhanced,as the ellipsoidal degree of the particle *** on a dimensional analysis,flow experiments were carried out to verify the behavior of ellipsoidal versus spherical particles in *** our theoretical and experimental results show that ellipsoidal particles approach the fluid velocity more quickly than spherical *** work would need to address effects of velocity gradients and rotation on particle behavior.

关键词： Solid-liquid two-phase flow Horizontal laminar flow Ellipsoidal particle Ellipsoidal degree Spherical particle Velocity distribution

Distinction of self-synchronous scrambled linear blockcodes based on multi-fractal spectrum

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Journal of Systems Engineering and Electronics 2016年第5期27卷 968-978页

作者： xinhao li min zhang shu'nan han quan yuan electronic engineering institute Hefei 230037China key laboratory of anhui electronic restricting technique Hefei 230037China

This study proposes a novel multi-fractal spectrumbasedapproach to distinguish linear block codes from its selfsynchronousscrambled codes. Given that the linear block codeand self-synchronous scrambled linear block code share the propertyof linear correlation, the existing linear correlation-basedidentification method is invalid for this case. This drawback can becircumvented by introducing a novel multi-fractal spectrum-basedmethod. Simulation results show that the new method has highrobustness and under the same conditions of bit error, the lowerthe code rate, the higher the recognition rate. Thus, the methodhas significant potential for future application in engineering.

关键词： linear block code self-synchronous scrambled code,multi-fractal spectrum statistical physics algorithm.

Flight control of a large-scale flapping-wing flying robotic bird:System development and flight experiment

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Chinese Journal of Aeronautics 2022年第2期35卷 235-249页

作者： Wenfu XU Erzhen PAN Juntao LIU Yihong LI han yuan School of Mechanical Engineering and Automation Harbin Institute of TechnologyShenzhen 518055China State Key Laboratory of Robotics and System Harbin Institute of TechnologyHarbin 150001China

Large-scale flapping-wing flying robotic birds have huge application potential in outdoor tasks,such as military reconnaissance,environment exploring,disaster rescue and so *** this paper,a multiple modes flight control method and system are proposed for a large-scale robotic bird which has 2.3 m wingspan and 650 g *** from small flapping wing aerial vehicle,the mass of its wings cannot be neglected and the flapping frequency are much ***,the influence of transient aerodynamics instead of only mean value are considered in attitude estimation and controller ***,flight attitude and trajectory are highly coupled,and the robot has only three actuators----one for wings flapping and two for tail adjustment,it is very difficult to simultaneously control the attitude and ***,a fuzzy control strategy is addressed to determine the command of each actuator by considering the priority of attitude stabilization,trajectory tracking and the flight ***,the on-board controller is designed based on *** not only satisfies the strict restrictions on mass,size,power and space but also meets the autonomous,semi-autonomous and manual flight control ***,the developed control system was integrated to the robotic prototype,*** experiments under different environment conditions such as sunny and windy weather were completed to verify the control method and system.

关键词： Autonomous flight control Flapping-wing Free RTOS HIT-Phoenix Robotic bird

Theoretical and experimental investigation on a liquid-gas ejector power cycle using ammonia-water

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Science China(Technological Sciences) 2013年第9期56卷 2289-2298页

作者： yuan han MEI Ning LI Yan YANG Shuai HU Siyuan han YiFang College of Engineering Ocean University of China

The purpose of this paper is to investigate a novel power cycle using low-temperature heat sources such as oceanic-thermal, biomass as well as industrial waste heat. Both a reheater and a liquid-gas ejector are used in this ammonia-water based cycle. Energy analysis and parametric analysis are performed to guide the theoretical performance and experimental investigation is done to verify the theoretical results. The results show that the generator pressure, heating source temperature and turbine outlet depressurization made by the ejector can affect the cycle performances. Besides, the experimental thermal efficiency is much lower than the theoretical one on account of the heat losses and irreversibility. Moreover, the performance of liquid-gas ejector is affected by primary flow pressure and temperature.

关键词： ammonia-water power cycle ejector efficiency

Synthetic Control Method for Crystallite Size of MOF-5

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Chemical Research in Chinese Universities 2014年第3期30卷 356-361页

作者： han Pengfei yuan Changfu XU Junyi LIU Jin School of Metallurgy and Environment Central South University Changsha 410083 t~ R. China

We reported a dripping solvothermal method for synthesizing metal-organic framework-5（MOF-5）. It started from separately dissolving Zn（NO3）2 and terephthalic acid（H2BDC） in dimethyl formamide（DMF）, and then dripping one solution into the other. Results of SEM, XRD and laser particle size distribution show that regular cubic-shaped and micro-crystallite powder of MOF-5 can be obtained. The d0.5（volume-median-diameter） values are 4.32 μm for particles prepared by dripping Zn（NO3）2 into H2BDC（ZH） and 9.32 μm for those prepared by dripping H2BDC into Zn（NO3）2（HZ）, much smaller than 22,7 μm that of particles prepared by the traditional adding water solvothermal method（L）. The standard deviations of the particle size distributions fitted by the GaussAmp model are 2.49, 4.38 and 15.4 respectively for ZH, HZ and L, further revealing narrower size distributions of particles prepared by the dripping method. In addition, the Langmuir specific surface areas are 923 m^2/g for ZH and 868 m^2/g for HZ. The TGA results present mass losses of 4.18% and 3.62% at 105 ℃, 17.19% and 14.78% at 245 ℃, 39.04% and 34.85% at 600℃ separately for ZH and HZ, which correspond to the removal of H20, DMF and the decomposition of MOF-5. This indicates that MOF-5 has a strong adsorption ability for small molecules. Besides, the mass loss of 48.39%（ZH） and 41.02%（HZ）between 400 ℃ and 600 ℃ are less than the theoretical value of 57.81% for MOF-5 decomposition to ZnO, suggesting that an impure phase with an extra amount of ZnO may exist in the cavities of MOF-5.

关键词： Metal-organic framework-5(MOF-5) Dripping solvothermal method Size distribution