WEI Chao QIAN Rengen LIN Shi XIAO Jimei University of Science and Technology Beijing
,
Beijing
,
China Dept.of Mathematics and Mechanics
,
University of Science and Technology Beijing
,
Bijing 100083
,
China
金属学报(英文版)
Based on the experimental results of the work-hardening processes of single crystals,the ac- commodation processes of polycrvstal deformation and the assumption of idealized polycrystal,the stress-strain relation of elasto-plastic deformation crystal was derived.The effect of orientation difference on the mechanical properties of the bicrvstalline specimens of aluminum was simulated by means of the finite element method(FEM)of elasto-plastic crystal.The results are in good agreement with the experimental results made by Clark and Chalmers in 1954.
关键词:
bicrystal
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null
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null
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null
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null
杨金瑞
,
余尚先
,
顾江楠
高分子材料科学与工程
通过对resol(羟甲基酚化合物和低分子量羟甲基酚树脂)DEPT135图谱的分析讨论,得到一系列计算resol微细结构参数的经验公式.根据DEPT135图谱可判断是否发生缩聚反应,根据经验公式可计算酚单体各个活性点参与反应百分率或酚羟基导入率、不同类型缩聚所占百分率及低分子量羟甲基酚树脂的平均核体数.
关键词:
羟甲基酚化合物
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羟甲基酚树脂
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DEPT135
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结构参数
GUO Chengbi ZHOU Weisheng Dalian Institute of Technology
,
Dalian
,
Liaoning
,
China Professor
,
Dept.of Shipbuilding
,
Dalian Institute of Technology
,
Dalian
,
Liaoning
,
China
金属学报(英文版)
The in-phase and out-of-phase thermal fatigue,the C-P type and P-C type isothermal fa- tigue of grey cast iron were experimentally studied.The fatigue life was evaluated analytically by using the elastic-plastic fracture mechanics method(mainly J integral).The results of ex- periments and calculations showed that the lifes of in-phase and C-P type fatigue are longer than that of out-of-phase and P-C type fatigue respectively within the same strain range. This is in contrast to the results of other materials such as low carbon steel.On the other hand, the predicted lifes are consistent with experimental results.This suggests that J integral as a mechanics parameter for characterizing the thermal fatigue strength of grey cast iron and the mechanics model and the calculation method developed here are efficient.A parameter ΔW_1 was proposed from energy aspect to characterize the capacity of crack propagation. The isothermal fatigue life is the same as the thermal fatigue life for identical ΔW_1 values.
关键词:
grey cast iron
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null
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null
Frontiers of Physics in China
In this paper, we present the elementary principles of nonlinear quantum mechanics (NLQM), which is based on some problems in quantum mechanics. We investigate in detail the motion laws and some main properties of microscopic particles in nonlinear quantum systems using these elementary principles. Concretely speaking, we study in this paper the wave-particle duality of the solution of the nonlinear Schrodinger equation, the stability of microscopic particles described by NLQM, invariances and conservation laws of motion of particles, the Hamiltonian principle of particle motion and corresponding Lagrangian and Hamilton equations, the classical rule of microscopic particle motion, the mechanism and rules of particle collision, the features of reflection and the transmission of particles at interfaces, and the uncertainty relation of particle motion as well as the eigenvalue and eigenequations of particles, and so on. We obtained the invariance and conservation laws of mass, energy and momentum and angular momentum for the microscopic particles, which are also some elementary and universal laws of matter in the NLQM and give further the methods and ways of solving the above questions. We also find that the laws of motion of microscopic particles in such a case are completely different from that in the linear quantum mechanics (LQM). They have a lot of new properties; for example, the particles possess the real wave-corpuscle duality, obey the classical rule of motion and conservation laws of energy, momentum and mass, satisfy minimum uncertainty re-lation, can be localized due to the nonlinear interaction, and its position and momentum can also be determined, etc. From these studies, we see clearly that rules and features of microscopic particle motion in NLQM is different from that in LQM. Therefore, the NLQM is a new physical theory, and a necessary result of the development of quantum mechanics and has a correct representation of describing microscopic particles in nonlinear systems, which can solve problems disputed for about a century by scientists in the LQM field. Hence, the NLQM built is very necessary and correct. The NLQM established can promote the development of physics and can enhance and raise the knowledge and recognition levels to the essences of microscopic matter. We can predict that nonlinear quantum mechanics has extensive applications in physics, chemistry, biology and polymers, etc.
关键词:
microscopic particle;nonlinear systems;nonlinear quantum mechanics;basic principle;motion rule;dynamic property;nonlinear Schrodinger;equation
LIANG Yong LI Ruiguo Institute of Metal Research
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Academia Sinica
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Shenyang 110015
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ChinaInstitute of Corrosion and Protection of Metals
,
Aademia Sinica
,
Shenyang
,
110015
,
China
材料科学技术(英文)
Recent advances in laser coating technology including laser cladding,laser surface alloying and laser vapour deposition in China are reviewed in this paper.
关键词:
laser
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null
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null
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null
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null
Journal of Physics D-Applied Physics
The dynamic aspects of linear elastic fracture mechanics applied to dielectric breakdown are studied. In the same direction as the fracture mechanics analogue for dielectric breakdown described previously by some researchers, this paper develops the intrinsic, rate-dependent bond breakdown micromechanism to account for the dynamic process of dielectric breakdown. The formulae of conducting microcrack growth rate and lifetime prediction are derived and applied to the experimental data of SiO2 films.
关键词:
sio2-films;oxides