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Microstructures and Tensile Properties of Isothermally-forgedTi-47Al-2Nb-1Cr-1V and Ti-47Al-2V-1Cr Alloys

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Journal of Materials Science & Technology 1997年第6期13卷 452-456页

作者： Qin, GW hao, sm Han, CX Northeastern Univ Dept Mat Sci & Engn Shenyang 110006 Peoples R China NW Inst Nonferrous Met Res Xian 710016 Peoples R China

Microstructures and room-temperature tensile properties of isothermally-forged gamma-base (gamma + alpha(2)) alloys in Ti-AI-Nb-Cr-V system with different heat treatments were investigated. The results show that the microstructures of Ti-47Al-2Nb-1Cr-1V and Ti-47Al-2V-1Cr (at. pet) alloys are mainly determined by heat treating temperature in the (alpha + gamma) two-phase field, and the joint additions of Nb, Ci and V in the Ti-47Al alloy affect T-alpha significantly. The microstructure of Ti-47Al alloy with additions of Nb, Cr and V (1 similar to 2 at. pat) can be duplex or nearly-lamellar by a suitable heat treatment after isothermal forging at 1000 degrees C for over 50% plastic strains. Therefore its tensile properties can be improved at room temperature.

关键词： Titanium alloys

Calculation of Phase Equilibria between Solid Solutions with Magnetic Transition by the Cluster Variation Method

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Journal of Materials Science & Technology 1997年第1期13卷 15-20页

作者： Liu, XJ Jiang, M hao, sm Yuan, RW NE UNIV TECHNOL DEPT MAT SCI & ENGNSHENYANG 110006PEOPLES R CHINA

By using the geometric analysis of grand potential, the molar grand potential-effective chemical potential curve of solution with magnetic transition can be obtained from the relevant molar free energy diagram, and it is shown that the grand potential and effective chemical potential can be separated into paramagnetic and magnetic terms. In addition, the CVM has been combined with the present magnetic transition free energy model such as M. Hillert and T. Nishizawa's models to calculate phase equilibria between solutions with magnetic transition, and this combined method has been applied to the alpha/gamma phase equilibrium in the Fe-Mn binary system and found to be feasible.

关键词： Iron alloys

Effects of Alloy Elements (C, B, Fe, Si) on the Ti-Al Binary Phase Diagram

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Journal of Materials Science & Technology 1999年第1期15卷 58-62页

作者： Li, JT Zong, YP hao, sm Northeastern Univ Dept Mat Sci & Engn Shenyang 110006 Peoples R China

The alpha(alpha(2))/gamma phase equilibria in Ti-Al-X(X=C,B,Fe,Si in at, pct) ternary systems were studied by equilibrium heat-treatment and EPMA. The results show that the addition of B to the Ti-Al binary system leads to a shift of both alpha(alpha(2))/[alpha(alpha(2))+gamma] and [(alpha(alpha(2))+gamma]/gamma phase boundaries to Al-rich side and 0.1 B addition decreases T-alpha by 18 degrees C. The addition of C leads to a shift of [alpha(alpha(2))+gamma]/gamma phase boundary to Al-rich side but the effect of 0.2 at, pet C addition on T-alpha is very slight. The addition of Fe results in alpha(alpha(2))/[alpha(alpha(2))+gamma] and [alpha(alpha(2))+gamma]/gamma phase boundaries shifting to Ti-rich side and 1.0 Fe addition increases T-alpha by 90 similar to 110 degrees C. The addition of Si leads to a shift of alpha(alpha(2))/[alpha(alpha(2))/[alpha(alpha(2))+gamma] phase boundary to Ti-rich side and the 0.3 Si addition increases T-alpha by 80 similar to 110 degrees C. The solubilities for C, B and Si in alpha(alpha(2)) phase are higher than those in the gamma phase but the solubility for Fe in alpha(alpha(2)) phase is lower than that in gamma phase.

关键词： MECHANICAL-PROPERTIES TITANIUM ALUMINIDE

EFFECT　OF　ANNEALING　TEMPERATURE　ON　TEXTURE　OF　COLD－ROLLED　Ni₄₇Ti₄₄Nb₉　SHEET

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中国有色金属学会会刊：英文版 1995年第1期5卷 88-93页

作者： YANG, GJ XIE, LY HU, WY DENG, J hao, sm NW INST NONFERROUS MET RES BAOJI 721014PEOPLES R CHINA NORTHEASTERN UNIV SHENYANG 110006PEOPLES R CHINA

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关键词： annealing temperature Ni47Ti44Nb9 texture ODF

Enhancing SAEAs with unevaluated solutions:a case study of relation model for expensive optimization

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Science China(Information Sciences) 2024年第2期67卷 41-58页

作者： hao hao Xiaoqun ZHANG Aimin ZHOU Institute of Natural Sciences Shanghai Jiao Tong University Shanghai Frontiers Science Center of Molecule Intelligent Syntheses School of Computer Science and Technology East China Normal University

Surrogate-assisted evolutionary algorithms(SAEAs) hold significant importance in resolving expensive optimization problems. Extensive efforts have been devoted to improving the efficiency of SAEAs through the development of proficient model-assisted solution selection methods, which, however, first requires generating high-quality solutions. The fundamental paradigm of evaluating a limited number of solutions in each generation within SAEAs reduces the variance of adjacent populations, thereby affecting the quality of offspring solutions. This is a frequently encountered issue yet receives little attention. To address the issue, this paper presents a framework using unevaluated solutions to enhance the efficiency of *** surrogate model is employed to identify high-quality solutions for the direct generation of new solutions without evaluation. To ensure dependable selection, we have introduced two tailored relation models to select the optimal solution and the unevaluated population. A comprehensive experimental analysis is performed on two test suites, which showcases the superiority of the relation model over regression and classification models in the solution selection phase. Furthermore, the surrogate-selected unevaluated solutions with high potential have been shown to enhance the efficiency of the algorithm significantly.

关键词： expensive optimization unevaluated solutions relation model surrogate-assisted evolutionary algorithm

A Global Optimality Principle for Fully Coupled Mean-field Control Systems

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 379-413页

作者： Tao hao School of Statistics and Mathematics Shandong University of Finance and EconomicsJinan 250014China

This paper concerns a global optimality principle for fully coupled mean-field control *** the first-order and the second-order variational equations are fully coupled mean-field linear FBSDEs. A new linear relation is introduced, with which we successfully decouple the fully coupled first-order variational equations. We give a new second-order expansion of Y^(ε) that can work well in mean-field framework. Based on this result, the stochastic maximum principle is proved. The comparison with the stochastic maximum principle for controlled mean-field stochastic differential equations is supplied.

关键词： optimal control global maximum principle fully coupled general mean-field FBSDE adjoint equation recursive utility

Nonclassical correlations in two-dimensional graphene lattices

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Communications in Theoretical Physics 2024年第4期76卷 72-79页

作者： hao Wang Shanghai Normal University Tianhua College ShangHai 201815China

We investigate nonclassical correlations via negativity,local quantum uncertainty(LQU)and local quantum Fisher information(LQFI)for two-dimensional graphene *** explicitly analytical expressions for negativity,LQU and LQFI are *** close forms of LQU and LQFI confirm the inequality between the quantum Fisher information and skew information,where the LQFI is always greater than or equal to the LQU,and both show very similar behavior with different ***,the effects of the different system parameters on the quantified quantum correlation are *** LQFI reveals more nonclassical correlations than LQU in a two-dimensional graphene lattice system.

关键词： negativity local quantum uncertainty(LQU) local quantum Fisher information(LQFI) graphene lattices nonclassical correlations

Machine learning-assisted smart epitaxy ofⅢ-Ⅴsemiconductors

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Science China Materials 2024年第9期67卷 3041-3042页

作者： Yue hao Key Laboratory of Wide Band Gap Semiconductor Technology School of MicroelectronicsXidian UniversityXi’an710071China

Semiconductor epitaxial growth is the front-end process for manufacturing microelectronic and optoelectronic *** beam epitaxy(MBE),capable of precisely controlling atomic layer deposition,has emerged as a crucial technique in chip atomic-level manufacturing[1].However,in semiconductor epitaxy,the heterogeneous nature of materials is complicated,and the growth condition fluctuations poses significant challenges in defect suppression[2],substantially impacting chip performance and yield.

关键词： optoelectronic smart semiconductors

A review on numerical studies of airflow dynamics and particle deposition in human respiratory system Author links open overlay panel

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Particuology 2024年第8期91卷 351-377页

作者： hao Jing Xinguang Cui School of Aerospace Engineering Huazhong University of Science and TechnologyWuhan430074China

Accurate assessment and prediction of airflow dynamics and particle deposition in the human respiratory tract are essential for human health,involving inhaled drugs for treating various diseases and toxic particles that can cause *** intricate process involves complex multiphase flow with distinct respiratory *** fluid dynamics(CFD)acts as a bridge,overcoming the limitations of in vivo and in vitro experiments and providing a means to fully comprehend and reveal the fundamental mechanisms of respiratory flow and particle behavior on a microscopic *** paper provides a comprehensive overview and concise summary of recent advancements in the numerical simulation of airflow and particle deposition in the human respiratory ***,it summarizes the transition of respiratory tract models from segmented models to emerging physiological characteristic models and whole-lung airway models,and the latest developments on the effects of key factors such as geometric variations,respiratory patterns,and particle physical/chemical properties on respiratory flow and particle deposition.A notable focus of this review is on emerging physiological characteristics models and their associated complex airflow and particle dynamics inside *** paper concludes with recommendations for future research to further advance the development of this field.

关键词： Airflow dynamics Particle deposition Human respiratory system Numerical modeling