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Supramolecular assemblies from single-chain hydrocarbon fluorocarbon hybrid bolaamphiphiles

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Chinese Journal of Chemistry 1996年第2期14卷 171-179页

作者： yu, b Hui, YZ CHINESE ACAD SCI SHANGHAI INST ORGAN CHEMSTATE KEY LAB BIOORGAN & NAT PROD CHEMSHANGHAI 200032PEOPLES R CHINA

Three types of single-chain hydrocarbon fluorocarbon hybrid bolaamphiphiles were synthesized. They readily formed different kinds of organized supramolecular assemblies, including vesicles, tapes, and micellar fibers, in aqueous solution. The aggregates morphology was characterized by transmission electron microscopy (TEM) after negative staining. The superstructures of these aggregates seemed to be determined by the geometry and the head group's properties of the corresponding amphiphiles..

关键词： assemblies single-chain hydrocarbon fluorocarbon hybrid bolaamphiphile

An analysis of the chaotic motion of particles of different sizes in a gas fluidized bed

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Particuology 2008年第6期6卷 549-556页

作者： Y.Q. Feng A.b. yu Lab for Simulation and Modelling of Particulate Systems School of Materials Science and Engineering University of New South Wales Sydney NSW 2052 Australia

The dynamic behavior of individual particles during the mixing/segregation process of particle mixtures in a gas fluidized bed is analyzed. The analysis is based on the results generated from discrete particle simulation, with the focus on the trajectory of and forces acting on individual particles. Typical particles are selected representing three kinds of particle motion： a flotsam particle which is initially at the bottom part of the bed and finally fluidized at the top part of the bed; a jetsam particle which is initially at the top part of the bed and finally stays in the bottom de-fluidized layer of the bed; and a jetsam particle which is intermittently joining the top fluidized and bottom de-fluidized layers. The results show that the motion of a particle is chaotic at macroscopic or global scale, but can be well explained at a microscopic scale in terms of its interaction forces and contact conditions with other particles, particle-fluid interaction force, and local flow structure. They also highlight the need for establishing a suitable method to link the information generated and modeled at different time and length scales.

关键词： Fluidization Segregation Discrete particle simulation Granular dynamics

Review of deployment technology for tethered satellite systems

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Acta Mechanica Sinica 2018年第4期34卷 754-768页

作者： b.S.yu H.Wen D.P.Jin State Key Laboratory of Mechanics and Control of Mechanical Structures Nanjing University of Aeronautics and Astronautics

Tethered satellite systems（TSSs） have attracted significant attention due to their potential and valuable applications for scientific research. With the development of various launched on-orbit missions, the deployment of tethers is considered a crucial technology for operation of a TSS. both past orbiting experiments and numerical results have shown that oscillations of the deployed tether due to the Coriolis force and environmental perturbations are inevitable and that the impact between the space tether and end-body at the end of the deployment process leads to complicated nonlinear phenomena. Hence, a set of suitable control methods plays a fundamental role in tether deployment. This review article summarizes previous work on aspects of the dynamics, control, and ground-based experiments of tether deployment. The relevant basic principles, analytical expressions, simulation cases, and experimental results are presented as well.

关键词： Tethered satellite Deployment Dynamics Control Experiment

MICROSTRUCTURE AND MECHANICAL PROPERTIES OF AZ91D EXTRUDED TUbE

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Acta Metallurgica Sinica(English Letters) 2006年第3期19卷 203-208页

作者： b.Y. yu C.L. bao H.W. Song Z. Liu H.P. yu School of Materials Science and Engineering Shenyang University of Technology Shenyang 110023 China

The effect of extrusion ratio on microstruetures and mechanical properties of magnesium alloy AZ91D extruded tube at 430℃ has been studied. After the evolution of microstracture and mechanical properties of AZ91D during extrusion were studied, the following parameters were obtained： tensile strength reached the climax value of 306.9MPa and elongation peak value of 10.1% at an extrusion ratio of 7.125, and with the increase of the extrusion ratio to 7.45, yield strength reached a top value of 285.795MPa with decreased tensile strength and elongation. It was concluded that mechanical properties of magnesium alloys AZ91D could be enhanced by adjusting the extrusion ratio near recrystallization.

关键词： magnesium tube microstructure tensile property

Linking discrete particle simulation to continuum process modelling for granular matter: Theory and application

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Particuology 2011年第4期9卷 342-357页

作者： H.P. Zhu Z.Y. Zhou Q.F. Hou A.b. yu School of Engineering University of Western Sydney Locked Bag 1797 Penrith NSW 2751 Australia Laboratory for Simulation and Mo-delling of Particulate Systems School of Materials Science and Engineering The University of New South Wales Sydney NSW 2052 Australia

Two approaches are widely used to describe particle systems： the continuum approach at macroscopic scale and the discrete approach at particle scale. Each has its own advantages and disadvantages in the modelling of particle systems. It is of paramount significance to develop a theory to overcome the disadvantages of the two approaches. Averaging method to link the discrete to continuum approach is a potential technique to develop such a theory. This paper introduces an averaging method, including the theory and its application to the particle flow in a hopper and the particle-fluid flow in an ironmaking blast furnace.

关键词： Particle flow Gas-solid flow Discrete approach Averaging method Hopper flow blast furnace

Conformational Analysis of Two Diosgenyl Saponins

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Chinese Chemical Letters 1997年第9期8卷 785-788页

作者： Liu, MZ Li, C yu, b Cheng, Mb Feng, CL Hui, YZ CHINESE ACAD SCI SHANGHAI INST ORGAN CHEMSTATE KEY LAB BIOORGAN & NAT PROD CHEMSHANGHAI 200032PEOPLES R CHINA

Diosgenyl alpha-L-rhamnopyranosyl-(1-->4)-beta-D-glucopyranosyl-(1-->6)-beta-D-glucopyranoside (1) and Diosgenyl alpha-L-rhamnopyranosyl-(1-->2)-beta-D-xylopyranoside (2) were shown to be fascinating ''facial amphiphi... 详细信息

关键词： DYNAMICS CALCULATIONS MOLECULAR-DYNAMICS NMR GLYCOSIDES

NUMERICAL SIMULATION OF TEMPERATURE FIELD ON FLASH bUTT WELDING FOR HIGH MANGANESE STEELS

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Acta Metallurgica Sinica(English Letters) 2005年第4期18卷 547-551页

作者： b.D. yu W.D. Song F. C. Zhang China Railway Shanhaiguan bridge Group Limited Company Shanhaiguan 066205 China College of Materials Science and Engineering Yanshan University Qinhuangdao 066004 China

An axial symmetry finite element model coupled with electricity-thermal effect was developed to study the temperature field distribution in process of the flash butt welding （FbW） of frog highmanganese steel. The influence of temperature dependent material properties and the contact resistance were taken into account in FEM ＇simulation. Meanwhile, the lost materials due to .splutter was resolved by using birth and death element. The result of analyzing data shows that the moddel in the FbW flashing is reasonable and feasible, and can exactly simulate the temperature field distribution. The modeling provides reference for analysis of welding technologies on the temperature field of high-manganese steel in FbW.

关键词： flash butt welding (FbW) numerical simulation high manganese steel,temperature field

Effect of base Material on Microstructure and Texture Evolution of a Ti–6Al–4V Electron-beam Welded Joint

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Acta Metallurgica Sinica(English Letters) 2017年第5期30卷 499-504页

作者： G.Q.Wang Z.b.Zhao b.b.yu J.R.Liu Q.J.Wang J.H.Zhang R.Yang J.W.Li School of Materials Science and Engineering University of Science and Technology of China Institute of Metal Research Chinese Academy of Sciences Science and Technology on Power beam Processes Laboratory Beijing Aeronautical Manufacturing Technology Research Institute

The effect of base material（bM） on microstructure and crystallographic orientation evolution of a Ti–6Al–4V electron-beam welded joint was investigated. Meanwhile, the crystallographic orientation of prior b grains was studied by advanced electron backscattered diffraction data processing. The inhomogeneity of microstructure within welded joint was formed due to the different microstructures of bM. by comparing microstructure details of the welded joint, including microstructure morphology and crystallographic orientation with those of the base material, it can be found that both the microstructure morphology and crystallographic orientation of the EbW joint would be controlled by bM.

关键词： Electron-beam welding Titanium alloys Prior b orientation Microstructure Texture

A new series of emodin derivatives with bone affinity

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Chinese Chemical Letters 2007年第2期18卷 141-144页

作者： Hong Chen[a]Email:chenhongtian06@*** Ying Wang[a][b] Ling Leng[a] Mao Sheng Cheng[b] Peng Fei yu[b] Jing Ze Zhang[a] [a]Medical College of Chinese People‘s Armed Police Forces Tianjin 300162 China [b]Shenyang Pharmaceutical University Shenyang 110016 China

A new series of bone affinity compounds were synthesized by linking emodin with 5-fluorouracil derivatives. Their bone affinities were established by hydroxyapative (HA) affinity experiment in vitro, and their cytosta... 详细信息

关键词： Emodin 5-Fluorouracil bone affinity Antitumor