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Influence of a liquid-filled compartment structure on the incoming shaped charge jet stability

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Defence Technology（防务技术） 2021年第2期17卷 571-582页

作者： x.D.zu z.x.Huang z.W.Guan x.C.Yin Y.M.zheng School of Mechanical Engineering Nanjing University of Science and TechnologyXiaolingwei 200Nanjing 210094China School of Engineering University of LiverpoolLiverpoolL693GQUK Department of Mechanics and Engineering Science Nanjing University of Science and TechnologyNanjing 210094China

Liquid-filled compartment structure consists of a bulk steel plate with matrix blind holes which are filled with liquid and a steel front plate to seal up the liquid with rings and *** liquid-filled compartment structure can resist the shaped charge warhead *** paper presents experimental and theoretical investigations of the penetration ability of the residual shaped charge jet emerging from the liquid-filled compartment structure after the penetration process at different impact *** the basis of shock wave propagation theory,the influence of the liquid-filled compartment structure on jet stability is *** interferences of the liquid backflow caused by a reflected shock wave and a back plate on jet stability under different impact angles are also *** addition,the range of the disturbed velocity segments of the jet at different impact angles and the penetration ability of the residual jet are obtained.A theoretical model is validated against the experimental penetration depths.

关键词： Compartment structure Shaped charge jet Shock wave Disturbance Stability

Effects of Nitridation on Properties of SiC Fiber and Interface of Ti Matrix Composite

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Journal of Materials Science & Technology 2002年第6期18卷 563-565页

作者： NanlinSHI z.x.Guo 等 InstituteofMetalResearch ChineseAcademyofSciencesShenyang110016China DepartmentofMaterials QueenMaryUniversityofLondonMileEndRoadLondonE14NSUK

Prenitridation of the TiBx coating surface of the Sigma SM1240 SiC fiber can form more stable compounds at the surface and obstruct the release of boron atoms into the Ti-based alloy matrix. The effect of nitridation on the tensile strength of the fiber was investigated in this work. Nitridation could degrade the tensile strength of the SiC fiber if the treating temperature and time are not optimized. The chemical reaction between the W core and SiC and the modification of fiber microstructure during the nitridation are responsible for the degradation in strength. The strength can be maintained by further optimization of the treating temperature and time. Therefore, stabilizing the surface of TiBx coating and hence the interface of the SiCf/Ti composite by the nitridation of the SiC fiber is a feasible technique for practical applications.

关键词： SiC fiber Surface coating Nitridation Tensile strength Interface

Effects of Cryoprotective Agents on the Bovine Articular Chondrocyte Viability

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Chemical Research in Chinese Universities 2002年第2期18卷 109-112页

作者： x.xu z.F.Cui Department of Engineering Science Oxford UniversityOxfordOX13PJUK

Cryopreservation is the process of choice for long term preservation of cells and tissues. In this study, the effects of cryoprotective agents, dimethyl sulfoxide(DMSO), glycerol and 1,2 propanediol on the bovine articular chondrocyte viability were examined experimentally. The CPA was added at the concentrations of 0 6, 0 9, 1 2 and 1 5 mol/L and at 4 ℃ and 37 ℃ and removed at 37 ℃ in one step. CPA stepwise addition and removal at 0 6 and 1 2 mol/L and at 37 ℃ was also tested as an alternative protocol. Cell volume excursion during DMSO addition and removal was estimated and correlated well with cell survival rates. Solution makeup affects cell survival rate and a stepwise protocol can improve the cell survival rates significantly.

关键词： Cryoprotective agent Chondrocyte Cell viability Cartilage

A two-scale method for identifying mechanical parameters of composite materials with periodic configuration

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Acta Mechanica Sinica 2006年第6期22卷 581-594页

作者： J.z. Cui x.G. Yu Academy of Mathematics and System Sciences Chinese Academy of Sciences Beijing 10080 China

In this paper, a two-scale method （TSM） is presented for identifying the mechanics parameters such as stiffness and strength of composite materials with small periodic configuration. Firstly, a formulation is briefly given for two-scale analysis （TSA） of the composite materials. And then a two-scale computation formulation of strains and stresses is developed by displacement solution with orthotropic material coefficients for three kinds of such composites structures, i.e., the tension column with a square cross section, the bending cantilever with a rectangular cross section and the torsion column with a circle cross section. The strength formulas for the three kinds of structures are derived and the TSM procedure is discussed. Finally the numerical results of stiffness and strength are presented and compared with experimental data. It shows that the TSM method in this paper is feasible and valid for predicting both the stiffness and the strength of the composite materials with periodic configuration.

关键词： Two-scale method Stiffness Strength Composite materials Small periodic configuration

Nonadiabatic geometric quantum computation protected by dynamical decoupling via the xxz Hamiltonian

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Frontiers of physics 2022年第3期17卷 111-119页

作者： x.Wu P.z.zhao Department of Physics Shandong UniversityJinan 250100China

Nonadiabatic geometric quantum computation protected by dynamical decoupling combines the robustness of nonadiabatic geometric gates and the decoherence-resilience feature of dynamical decoupling. Solid-state systems provide an appealing candidate for the realization of nonadiabatic geometric quantum computation protected dynamical decoupling since the solid-state qubits are easily embedded in electronic circuits and scaled up to large registers. In this paper, we put forward a scheme of nonadiabatic geometric quantum computation protected by dynamical decoupling via the xxz Hamiltonian, which not only combines the merits of nonadiabatic geometric gates and dynamical decoupling but also can be realized in a number of solid-state systems, such as superconducting circuits and quantum dots.

关键词： nonadiabatic geometric quantum computation dynamical decoupling xxz Hamiltonian

Characteristics of x/γ-ray radiations by intense laser interactions with high-z solids: The role of bremsstrahlung and radiation reactions

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Matter and Radiation at Extremes 2018年第6期3卷 293-299页

作者： D.Wu W.Yu Y.T.zhao S.Fritzsche x.T.He State Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine Mechanics201800 ShanghaiChina College of Science Xi'an Jiaotong UniversityXi'an 710049China Helmholtz Institute Jena D-07743 JenaGermany Theoretisch-Physikalisches Institut Friedrich-Schiller-University JenaD-07743 JenaGermany Key Laboratory of HEDP of the Ministry of Education CAPTState Key Laboratory of Nuclear Physics and TechnologyPeking UniversityBeijing100871China

In this work, characteristics of x/γ-ray radiations by intense laser interactions with high-z solids are investigated by means of a newlydeveloped particle-in-cell (PIC) simulation code. The PIC code takes advantage of the recently developed ionization and collision dynamicsmodels, which make it possible to model different types of materials based on their intrinsic atomic properties. Within the simulations, bothbremsstrahlung and nonlinear Compton scatterings have been included. Different target materials and laser intensities are considered forstudying the parameter-dependent features of x/γ-ray radiations. The relative strength and angular distributions of x/γ ray productions frombremsstrahlung and nonlinear Compton scatterings are compared to each other. The threshold under which the nonlinear Compton scatteringsbecome dominant over bremsstrahlung is also outlined.

关键词： Particle-in-cell simulations Bremsstrahlung Nonlinear Compton scattering Laser-solid interactions

Morphology Control and Optical Absorption Properties of Ag Nanoparticles by Ion Implantation

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Journal of Materials Science & Technology 2009年第5期25卷 669-672页

作者： G.x. Cai F. Ren x.H. xiao L.x. Fan x.D. zhou C.z. Jiang Key Laboratory of Acoustic and Photonie Materials and Devices of Ministry of Education Wuhan University Wuhan 430072 China

Ion implantation is a powerful method for fabricating nanoparticles in dielectric. For the actual application of nanoparticle composites, a careful control of nanoparticles has to be achieved. In this letter, the size, distribution and morphology of Ag nanoparticles are controlled by controlling the ion current density, ion implantation sequence and ion irradiation dose. Single layer Ag nanoparticles are formed by Ag^＋ ion implantation at current density of 2.5 μ^A/cm2. By Ag and Cu ions sequential implantation, the size of single layer Ag nanoparticles increases. While, by Cu and Ag ions sequential implantation, uniform Ag nanoparticles with wide distribution are formed. The morphology of Ag nanoparticles changes to hollow and sandwiched nanoparticles by Cu^＋ ion irradiation to doses of 3×10^16 and 5×10^16 ions/cm^2. The optical absorption properties of Ag nanoparticles are also tailored by these ways.

关键词： Nanoparticles Ion implantation Transmission electron microscopy

Effect of Grain Boundary Engineering on the Work Hardening Behavior of AL6xN Super‑Austenitic Stainless Steel

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Acta Metallurgica Sinica(English Letters) 2023年第4期36卷 681-693页

作者： x.J.Guan z.P.Jia M.A.Nozzari Varkani x.W.Li Department of Materials Physics and Chemistry School of Materials Science and EngineeringNortheastern UniversityShenyang 110819China State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China Key Laboratory for Anisotropy and Texture of Materials Ministry of EducationNortheastern UniversityShenyang 110819China

To examine the influence of grain boundary engineering(GBE)on the work hardening behavior,the tensile tests were carried out on the non-GBE and GBE AL6xN super-austenitic stainless steel(ASS)samples with a comparable grain size at two strain rates of 10^(-2)s^(-1)and 10^(-4)s^(-1).The evolution of deformation microstructures was revealed by transmission electron microscopy(TEM)and quasi-in situ electron backscatter diffraction(EBSD)*** results show that the influence of GBE on the mechanical properties of AL6xN super-ASS is mainly manifested in the change of work hardening *** the early stage of plastic deformation,GBE samples show a slightly lowered work hardening rate,since the special grain boundaries(SBs)of a high fraction induce a higher dislocation free path and a weaker back stress;however,with increasing plastic deformation amount,the work hardening rate of GBE samples gradually surpasses that of non-GBE samples due to the better capacity of maintainable work hardening that is profited from the inhibited dislocation annihilation by *** a word,the enhanced capacity of sustained work hardening effectively postpones the appearance of necking point and thus efficaciously ameliorates the ductility of GBE samples under the premise of little changes in yield strength and ultimate tensile strength.

关键词： AL6xN super-austenitic stainless steel Grain boundary engineering Work hardening behavior Quasi-in situ observation Ductility

Theory and applications of artificial endocrine system-an overview

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哈尔滨工程大学学报 2006年第B07期27卷 340-345页

作者： CUI Wei QIANG Sheng GAO x z Department of Control Science and Engineering Harbin Institute of Technology Harbin 150001 China PLA corps 66455 Institute of Intelligent Power Electronics Helsinki University of Technology Espoo Finland

Inspired by the biological endocrine system, the Artificial Endocrine System (AES) has been proposed and investigated during the past decade. As a novel branch of computational intelligence methods, it has its unique and distinguishing features. This paper intends to give an overview of the current research work in the AES. The preliminary theory of the AES, which is based on the simplified mathematic models of natural endocrine system, is first introduced here. Some typical AES algorithms and their applications are also briefly discussed. Finally, a few remarks and conclusions are made.

关键词：人工内分泌系统激素机器人技术智能计算