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Journal of Wuhan University of Technology(Materials Science) 2014年第5期29卷 1049-1056页

作者：杨晓敏侯华 zhao yuhong YANG Ling HAN Peide College of Materials Science and Engineering North University of China College of Materials Science and Engineering Taiyuan University of Technology

First-principles calculations have been carried out to investigate the structural stabilities, electronic structures and elastic properties of Mg17Al12, Al2Ca and Al4Sr phases. The optimized structural parameters are in good agreement with the experimental and other theoretical values. The calculated formation enthalpies and cohesive energies show that Al2Ca has the strongest alloying ability, and Al4Sr has the highest structural stability. The densities of states （DOS）, Mulliken electronic populations, and electronic charge density difference are obtained to reveal the underlying mechanism of structural stability. The bulk modulus, shear modulus, Young＇s modulus, and Poisson＇s ratio are estimated from the calculated elastic constants. The mechanical properties of these phases are further analyzed and discussed. The Gibbs free energy and Debye temperature are also calculated and discussed.

关键词： Mg-Al alloys electronic structure elastic properties thermodynamics properties first- principles

Dissolution and reprecipitation of 14H-LPSO structure accompanied by dynamic recrystallization in hot-extruded Mg_(89)Y_(4)Zn_(2)Li_(5) alloy

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Journal of Magnesium and Alloys 2023年第4期11卷 1408-1421页

作者： Wei Liu Yu Su Yuntao Zhang Liwen Chen Hua Hou yuhong zhao College of Materials Science and Engineering North University of ChinaTaiyuan 030051China

We investigate the variation induced in long-period stacking ordered(LPSO)structures,dynamic recrystallization(DRX),and mechanical performance of hot-extruded Mg89Y4Zn2Li5 alloys fabricated at different extrusion speeds(Ve=0.4,0.8,1.0,1.2 mm/s)and die angles(α=30°,60°,90°)under 400℃,the dissolution and reprecipitation of 14H LPSO structure accompanied by DRX process are then clarified in *** all extrusion conditions,the block 18R LPSO structures elongate in the extrusion direction,while the lamellar 14H LPSO structures dissolve under the deformation *** addition,due to discontinuous and continuous DRX mechanisms,all hot-extruded alloys have a full DRX microstructure consisting of equiaxed recrystallized grains,but the DRX grain size reduces when both extrusion speed and die angle *** that,in the interior of DRX grains,thin LPSO lamellae mixing 14H,18R and 24R structures nucleate and dynamically precipitate due to the dissolution of the original lamellar 14H LPSO ***,the hot-extruded Mg_(89)Y_(4)Zn_(2)Li_(5)alloy becomes stronger as decreasing of the extrusion speed and die angle,whereas the ductility remains nearly ***,the hotextruded Mg_(89)Y_(4)Zn_(2)Li_(5)alloy achieves an excellent strength-ductility balance at a relatively low extrusion speed(0.4 mm/s)and small die angle(30°)mainly due to the elongated 18R LPSO structure,fine and full DRX microstructure,thin mixed LPSO precipitates in the DRX grains,twins and dislocations.

关键词： Magnesium Extrusion LPSO Recrystallization Precipitation

Phase-Field Simulation of δ Hydride Precipitation with Interfacial Anisotropy

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Computers, Materials & Continua 2023年第11期77卷 1425-1443页

作者： Hailong Nie Xincheng Shi Wenkui Yang Kaile Wang yuhong zhao School of Materials Science and Engineering Collaborative Innovation Center of Ministry of Education and Shanxi Province for High-Performance Al/Mg Alloy MaterialsNorth University of ChinaTaiyuan030051China Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing100083China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang110004China

Previous studies ofδhydride in zirconium alloys have mainly assumed an isotropic *** practice,the difference in crystal structure at the interface between the matrix phase and the precipitate phase results in an anisotropic *** the purpose of probing the real evolution ofδhydrides,this paper couples an anisotropy function in the interfacial energy and interfacial *** influence of anisotropic interfacial energy and interfacial mobility on the morphology ofδhydride precipitation was investigated using the phase-field *** results show that the isotropy hydride precipitates a slate-like morphology,and the anisotropicδhydride precipitates at the semi-coherent and non-coherent interfaces exhibited parallelogram-like and needle-like,which is consistent with the actual experimental *** with the coherent interface,the semi-coherent or non-coherent interface adjusts the lattice mismatch,resulting in lower gradient energy that is more consistent with the true interfacial ***,an important chain of relationships is proposed,in the range of I_(x)1.5I_(x)),with the increase of the anisotropic mobility I_(y) in the y-axis,the gradient energy increases(decreases),the tendency of the non-coherent(semi-coherent)relationship at the interface,and the precipitation rate of hydride decreases(increases).Furthermore,the inhomogeneous stress distribution around the hydride leads to a localized enrichment of the hydrogen concentration,producing a hydride *** study of interfacial anisotropy is informative for future studies ofδhydride precipitation orientation and properties.

关键词： Zirconium δhydride phase-field method interfacial anisotropy interfacial mobility

Special function of nestin^+ neurons in the medial septum-diagonal band of Broca in adult rats

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Neural Regeneration Research 2014年第3期9卷 308-317页

作者： yuhong zhao Kaihua Guo Dongpei Li Qunfang Yuan Zhibin Yao Department of Anatomy and Neurobiology Zhongshan School of Medicine Sun Yat-sen University

Nestin＋ neurons have been shown to express choline acetyltransferase （CHAT） in the medial septum-diagonal band of Broca in adult rats. This study explored the projection of nestin＋ neu-rons to the olfactory bulb and the time course of nestin＋ neurons in the medial septum-diagonal band of Broca in adult rats during injury recovery after olfactory nerve transection. This study observed that all nestin＋ neurons were double-labeled with ChAT in the medial septum-diagonal band of Broca. Approximately 53.6% of nestin~ neurons were projected to the olfactory bulb and co-labeled with fast blue. A large number of nestin~ neurons were not present in each region of the medial septum-diagonal band of Broca. Nestin＋ neurons in the medial septum and vertical limb of the diagonal band of Broca showed obvious compensatory function. The number of nestin＋ neurons decreased to a minimum later than nestin/CHAT＋ neurons in the medial sep- turn-diagonal band of Broca. The results suggest that nestin＋ cholinergic neurons may have a closer connection to olfactory bulb neurons. Nestin＋ cholinergic neurons may have a stronger tolerance to injury than Nestin/CHAT＋ neurons. The difference between nestin＋ and nestin-/ ChAT＋ neurons during the recovery process requires further investigations.

关键词： nerve regeneration nestin choline acetyl transferase neurotransmitter medial sep-turn-diagonal band of Broca olfactory bulb olfactory nerve transection the Guangdong NaturalScience Foundation of China neural regeneration

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软件物料清单的应用与发展研究

北方工业大学学报 2024年第1期36卷 37-49页

作者：牟金帅刘冬梅赵宇红内蒙古科技大学信息工程学院包头014010

随着计算机技术的快速发展,软件已成为人们生活中不可或缺的一部分,并且软件安全已经成为一个备受关注的焦点议题。同时,软件供应链多次受到攻击。为了深入了解软件的安全及其组成成分,产生了软件物料清单这一关键概念。软件物料清单的... 详细信息

随着计算机技术的快速发展,软件已成为人们生活中不可或缺的一部分,并且软件安全已经成为一个备受关注的焦点议题。同时,软件供应链多次受到攻击。为了深入了解软件的安全及其组成成分,产生了软件物料清单这一关键概念。软件物料清单的目的是提供软件供应链的透明度和可管理性。通过明确列出软件中使用的组件和其相关信息,软件物料清单可以帮助企业追踪和管理软件的来源、版本、许可证信息等。这有助于降低供应链风险,确保软件的合规性,并提高安全性。本文从软件物料清单国内外现状到其特点和应用做出了介绍,同时详细说明了软件物料清单在软件供应链安全中的使用,并以此为切入点,通过对工具的对比,提出了未来软件物料清单的发展方向并表明了软件物料清单的重要性。

关键词：软件物料清单软件供应链软件安全供应链风险管理

Atomic Scale Computer Simulation for Early Precipitation Process of Ni75Al6Vi9 Alloy

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Journal of Materials Science & Technology 2003年第Z1期19卷 17-19页

作者： yuhong zhao Hua HOU Hong XU Yongxin WANG Zheng CHEN Xiaodong SUN Department of Materials Science and Engineering Northwestern Polytechnical University Xian 710072 China Department of Materials Engineering North China Institute of Technology Taiyuan 030051 China Department of Materials Engineering North China Institute of Technology Taiyuan 030051 China Department of Materials Science and Engineering Northwestern Polytechnical University Xian 710072 China Department of Materials Science and Engineering Northwestern Polytechnical University Xian 710072 China The Army Representative Agency in 674 Factory State-Owned Harbin 151005 China

The atomic scale computer simulation for initial precipitation mechanism of Ni75Al6V19 alloy was carried out for the first time by employing the microscopic diffusion equation. The initial precipitation process was invest igated throughsimulating the atomic pictures and calculating the order parameters of the two kinds of ordered phases. Simulationresults show that the γ′ordered phase precipitated earlier than θ ordered phase by congruent ordering+spinodal decomposition mechanism and thus produced a nonstoicheometric γ′ single ordered phase. Then, the nonstoichiometricθ phase precipitated by a non-classical nucleation and growth mechanism at the APBS of γ′ phase.

关键词： Precipitation mechanism, Ni75Al6V19 alloy, γ′ (Ni3Al) ordered phase, θ (Ni3V) ordered phase, Computer simulation

ω-Assisted refinement of α phase and its effect on the tensile properties of a near β titanium alloy

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Journal of Materials Science & Technology 2020年第9期44卷 24-30页

作者： Ruifeng Dong Jinshan Li Hongchao Kou Jiangkun Fan yuhong zhao Hua Hou Li Wu College of Materials Science and Engineering North University of ChinaTaiyuan 030051China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China

In this work, the phase transformation sequence during the continuous heating process(3℃/min) was investigated in a near β titanium alloy. The results show that the staring formation of ω phase is about267℃, and the ending precipitation temperature about 386℃ during the heating process. When the heating temperature is greater than 485℃, there are no ω phase detected within the β matrix. Combined with the microstructural characterization, it is found that ω phase facilitates the nucleation of αphase nearby the ω/β interface and has a great effect on the refinement for α phase. As compared with the specimens directly aged, the specimens with ω-assisted refinement of α phase possess high tensile strength, but there is no yield stage detected on their stress-strain curve. Combined with the analyses of the fracture morphology, the specimens with ω-assisted refinement of α phase present a brittle *** is mainly ascribed to its relatively lager width of grain boundaries and the absence of widmanst?ttenα precipitates.

关键词： Neartitanium alloy Continuous heating Phase transformation -Assisted nucleation Precipitation Tensile properties

Phase-field simulation of lack-of-fusion defect and grain growth during laser powder bed fusion of Inconel 718

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International Journal of Minerals,Metallurgy and Materials 2023年第11期30卷 2224-2235页

作者： Miaomiao Chen Renhai Shi Zhuangzhuang Liu Yinghui Li Qiang Du yuhong zhao Jianxin Xie Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083China Key Laboratory for Advanced Materials Processing(MOE) Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China Beijing Laboratory of Metallic Materials and Processing for Modern Transportation Institute for Advanced Materials and TechnologyUniversity of Science and Technology BeijingBeijing 100083China SINTEF Industry Oslo 0314Norway School of Materials Science and Engineering North University of ChinaTaiyuan 030051China

The anisotropy of the structure and properties caused by the strong epitaxial growth of grains during laser powder bed fusion(L-PBF)significantly affects the mechanical performance of Inconel 718 alloy components such as turbine *** defects(lack-of-fusion Lo F)in components processed via L-PBF are detrimental to the strength of the *** purpose of this study is to investigate the effect of laser scanning parameters on the epitaxial grain growth and LoF formation in order to obtain the parameter space in which the microstructure is refined and LoF defect is *** temperature field of the molten pool and the epitaxial grain growth are simulated using a multiscale model combining the finite element method with the phase-field *** LoF model is proposed to predict the formation of LoF defects resulting from insufficient melting during *** mitigation and grain-structure control during L-PBF can be realized simultaneously in the *** simulation shows the input laser energy density for the as-deposited structure with fine grains and without LoF defects varied from 55.0–62.5 J·mm^(-3)when the interlayer rotation angle was 0°–90°.The optimized process parameters(laser power of 280 W,scanning speed of 1160 mm·s^(-1),and rotation angle of 67°)were computationally *** these conditions,the average grain size was 7.0μm,and the ultimate tensile strength and yield strength at room temperature were(1111±3)MPa and(820±7)MPa,respectively,which is 8.8%and10.5%higher than those of *** results indicating the proposed multiscale computational approach for predicting grain growth and Lo F defects could allow simultaneous grain-structure control and defect mitigation during L-PBF.

关键词： Inconel 718 alloy laser powder bed fusion scanning parameter optimization lack-of-fusion phase-field method finite element method

Coalescence of Al_(0.3)CoCrFeNi polycrystalline high-entropy alloy in hot-pressed sintering: a molecular dynamics and phase- field study

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npj Computational Materials 2023年第1期9卷 424-436页

作者： Qingwei Guo Hua Hou Kaile Wang Muxi Li Peter K.Liaw yuhong zhao School of Materials Science and Engineering Collaborative Innovation Center of Ministry of Education and Shanxi Province for High-performance Al/Mg Alloy MaterialsNorth University of ChinaTaiyuan 030051P R China School of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024P R China Department of Materials Science and Engineering The University of TennesseeKnoxvilleTNUSA Beijing Advanced Innovation Center for Materials Genome Engineering University of Science and Technology BeijingBeijing 100083P R China Institute of Materials Intelligent Technology Liaoning Academy of MaterialsShenyang 110004P R China

Existing hot sintering models based on molecular dynamics focus on single-crystal *** work proposes a new multiparticle model based on molecular dynamics to investigate coalescence kinetics during the hot-pressed sintering of a polycrystalline Al_(0.3)CoCrFeNi high-entropy *** accuracy and effectiveness of the multiparticle model are verified by a phase-field *** this model,it is found that when the particle contact zones undergo pressure-induced evolution into exponential power creep zones,the occurrences of phenomena,such as necking,pore formation/filling,dislocation accumulation/decomposition,and particle rotation/rearrangement are *** on tensile test results,Young’s modulus of the as-sintered Al_(0.3)CoCrFeNi high-entropy alloy is calculated to be 214.11±1.03 GPa,which deviates only 0.82%from the experimental value,thus further validating the feasibility and accuracy of the multiparticle model.

关键词： alloy creep entropy

基于AHP的干旱半干旱区丰产型文冠果优良单株选择

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经济林研究 2024年第2期42卷 267-274页

作者：赵玉红周玉丽王艳霞赵明曾万祺王艺林兰晓东武龙庆甘肃省祁连山水源涵养林研究院甘肃张掖734000

【目的】筛选适宜在干旱半干旱区栽植的丰产型文冠果优良单株,丰富区域文冠果丰产型种质资源,为特色文冠果产业发展奠定资源基础。【方法】在专家打分和田间物候观测的基础上,运用AHP(层次分析法),从生长特性、产量指标、生态适应性3个... 详细信息

【目的】筛选适宜在干旱半干旱区栽植的丰产型文冠果优良单株,丰富区域文冠果丰产型种质资源,为特色文冠果产业发展奠定资源基础。【方法】在专家打分和田间物候观测的基础上,运用AHP(层次分析法),从生长特性、产量指标、生态适应性3个维度,产量、种仁含油量、树高、干径、冠幅、抗涝性、抗寒性、耐盐碱性、抗旱性、抗病虫害性等10个指标构建丰产单株综合评价模型,通过对评价指标两两比较,从其对筛选目标的相对重要性得出权重值,在检验一致性合理的基础上根据各指标的评分值和权重值运用公式Y=ΣW_(I)×X_(i)计算综合得分并排序,最终得出筛选结果。【结果】评价模型各矩阵的CR生长特性(0.2583)>生态适应性(0.1047),方案层中10个要素权重排序为产量(0.5308)>冠幅生长量(0.1241)>种仁含油量(0.1062)>干径生长量(0.1047)>抗旱性(0.0449)>树高生长量(0.0294)>抗涝性(0.0227)>抗盐碱性(0.0206)>抗寒性(0.0109)>抗病虫害性(0.0057)。最终根据加权得分值将25个候选单株排序,选出了综合得分高出平均值的12个单株,确定为此次选优选出的丰产型优良单株,分别为HJ04、HJ05、HJ08、HJ09、HJ12、HJ13、HJ14、HJ17、HJ19、HJ20、HJ22、HJ23。【结论】运用AHP筛选出的干旱半干旱区文冠果丰产型优良单株各评价指标的权重比例符合筛选准则,对照连续5年的观测数据,筛选出的12个优良单株和其在生产中的实际表现是一致的,具有丰产、优质、适应性好、长势强的特性,可以用作下一步决选单株的候选株进行子代测定,为其作为干旱半干旱区丰产型良种并进一步推广繁育提供了科学依据。

关键词： AHP 丰产型单株选择干旱半干旱区文冠果