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Formability of AA 2219-O sheet under quasi-static,electromagnetic dynamic,and mechanical dynamic tensile loadings

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Journal of Materials Science & Technology 2021年第11期70卷 125-135页

作者： hongliang Su Liang Huang Jianjun Li Wang xiao Hui Zhu Fei Feng Hongwei Li Siliang Yan State Key Laboratory of Materials Processing and Die&Mould Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074China State Key Laboratory of Solidification Processing School of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072China School of Materials Science and Engineering Hefei University of TechnologyHefei 230009China

The mechanism by which electromagnetic forming(EMF)enhances the formability of metals is unclear owing to the coupling effect of multi-physics *** the present work,the associated formability improvement mechanisms were qualitatively categorized and *** was realized by comparing the formability of fully annealed 2219 aluminum alloy(AA 2219-O)sheet under quasi-static(QS),electromagnetic dynamic(EM),and mechanical dynamic(MD)tensile *** was found that the forming limit of AA 2219-O sheet under EM tensile loading was significantly(45.4%)higher than that under QS tensile loading,and was marginally(3.7%–4.3%)higher than that under MD tensile *** addition,the forming limit of AA 2219-O sheet demonstrated a negative dependency on the strain rate within the range of the dynamic tensile tests *** deformation conditions common to EM and MD tensile loadings were responsible for the significant formability improvement compared with QS tensile *** particular,the inertial effect was *** different deformation conditions that distinguish EM tensile loading from MD tensile loading resulted in the marginal improvement in *** was caused by the absence of a sustaining contact force at the later deformation stage and the lower strain *** body force exerted little influence on the formability improvement,and the thermal effect under the two dynamic tensile loadings was negligible.

关键词： Formability Aluminum alloy sheet Quasi-static Electromagnetic dynamic Mechanical dynamic Tensile loading

Improvement in the piezoelectric temperature stability of(K_(0.5)Na_(0.5))NbO_3 ceramics

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Chinese Science Bulletin 2011年第22期56卷 2389-2393页

作者： ZHAO JingBo DU hongliang QU ShaoBo ZHANG HongMei XU Zhuo The College of Science Air Force Engineering University Xi'an 710051 China State Key Laboratory of Electrical Insulation and Power Equipment Xi'an Jiaotong University Xi'an 710049 China Electronic Materials Research Laboratory Key Laboratory of Educational Ministry Xi'an Jiaotong University Xi'an 710049 China

Through an analysis of the temperature stability of(K0.5Na0.5)NbO3(KNN)based ceramics and KNN solid solutions,we propose a method to enhance the temperature stability of KNN *** materials are valuable for their piezoelectric *** verify the feasibility of this method,0.9(K1-xNax)NbO3-0.06LiNbO3-0.04CaTiO3(KNLN-CaTiO3)ceramics were designed,and their structure and properties were *** results show that KNLN-CaTiO3(x=0.54)ceramics have a good temperature stability over a wide temperature range(25-320°C).Also,they have good piezoelectric properties(d33=152 pC/N in x=0.54).This result confirms the feasibility of our proposed solution for improving the piezoelectric properties of KNN-based ceramics that have poor temperature stability.

关键词：温度稳定性压电性能陶瓷设计 CaTiO3 KNN 温度范围材料

Evolution of molecular structure of TATB under shock loading from transient Raman spectroscopic technique

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Defence Technology（防务技术） 2024年第3期33卷 613-620页

作者： hongliang Kang Xue Yang Wenshuo Yuan Lei Yang xinghan Li Fusheng Liu Zhengtang Liu Qijun Liu Bond and Band Engineering Group School of Physical Science and TechnologySouthwest Jiaotong UniversityChengdu 610031China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi'an 710072China

By combination of the transient Raman spectroscopic measurement and the density functional theoretical calculations,the structural evolution and stability of TATB under shock compression was *** to the improvement in synchronization control between two-stage light gas gun and the transient Raman spectra acquisition,as well as the sample preparation,the Raman peak of the N-O mode of TATB was firstly observed under shock pressure up to 13.6 GPa,noticeably higher than the upper limit of 8.5 GPa reported in available *** taking into account of the continuous shift of the main peak and other observed Raman peaks,we did not distinguish any structural transition or any new ***,both the present Raman spectra and the time-resolved radiation of TATB during shock loading showed that TATB exhibits higher chemical stability than previous *** reveal the detailed structural response and evolution of TATB under compression,the density functional theoretical calculations were conducted,and it was found that the pressure make N-O bond lengths shorter,nitro bond angles larger,and intermolecular and intra-molecular hydrogen bond interactions *** observed red shift of Raman peak was ascribed to the abnormal enhancement of H-bound effect on the scissor vibration mode of the nitro group.

关键词： TATB Raman spectra Structural evolution Shock loading

陕西省图书信息后备人才基本知识与基本技能培养研究

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图书情报工作 2002年第4期46卷 40-46页

作者：牛红亮西北大学公共管理学院西安710069

立足陕西,通过对图书信息后备人才所应具备基本知识和基本技能的分析,确立图书信息专业的培养目标,明确图书信息专业课程设置应遵循的原则。介绍陕西省各教学单位课程体系改革和课程设置情况,并指出在课程设置上要处理好几对关系,图书... 详细信息

立足陕西,通过对图书信息后备人才所应具备基本知识和基本技能的分析,确立图书信息专业的培养目标,明确图书信息专业课程设置应遵循的原则。介绍陕西省各教学单位课程体系改革和课程设置情况,并指出在课程设置上要处理好几对关系,图书信息专业毕业生应获得知识能力以及陕西地区图书信息教学单位存在的问题。

关键词：陕西图书信息后备人才基本知识基本技能人才培养图书信息专业教育培养目标课程设置课程体系改革

U–Pb ages and Hf isotopes for detrital zircons from quartzite in the Paleoproterozoic Songshan Group on the southwestern margin of the North China Craton

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Chinese Science Bulletin 2008年第18期53卷 2828-2839页

作者： DIWU ChunRong SUN Yong YUAN HongLin WANG hongliang ZHONG xingPing LIU xiaoMing State Key Laboratory of Continental Dynamics Department of Geology Northwest University Xi'an 710069 China

In situ U-Pb dating and Lu-Hf isotopic analysis were carried out for detrital zircons from quartzite in the Paleoproterozoic Songshan Group on the southern margin of the North China Craton (NCC). The re- sults provide further constraints on the crustal formation and evolution history of NCC. Four 207Pb/206Pb age populations were obtained from 99 analyses, with clusters at ~3.40 Ga, 2.77―2.80 Ga, ~2.50 Ga and 2.34 Ga, respectively. The 3.40 Ga old zircons have similar Hf isotopic compositions to those from Ar- chean rocks in the Jidong and Anshan areas of NCC. However, crustal remnants older than 3.6 Ga have been identified in the southern margin of NCC, the South China Craton, the northwestern part of the Qinling Orogen and its adjacent area. Thus, it is not easy to trace the source rock from which the 3.40 Ga detrital zircons were derived. It can be inferred that the crustal remnants older than 3.40 Ga might have been widely distributed in the North China Craton. The 2.77―2.80 Ga zircons make up a relatively small proportion and have the highest εHf (t) values (up to 6.1±1.6), consistent with the Hf isotopic composition of the depleted mantle at 2.83 Ga. Their single-stage Hf model age of 2.83 Ga is close to their crystallized age, suggesting that their source rocks were extracted from the contemporaneous depleted mantle. The ~2.50 Ga zircon grains constitute about 85% of the total grain population and their Hf isotopic compositions indicate major growth of juvenile crust at ~2.50 Ga but minor reworking of ancient crust. The youngest zircon dated in this study gave an U-Pb age of 2337±23 Ma, which can be considered the maximum depositional age of the formation of the Songshan Group.

关键词：锆石中国北方铪同位素地质探测

Temperature dependence on the electrical and physical performance of InAs/AlSb heterojunction and high electron mobility transistors

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Chinese Physics B 2018年第9期27卷 489-494页

作者： Jing Zhang hongliang Lv Haiqiao Ni Zhichuan Niu Yuming Zhang School of Microelectronics Xidian University and Key Laboratory of Wide Band-Gap Semiconductor Materials and DevicesXi＇an 710071China State Key Laboratory for Superlattices and Microstructures Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China

In this report, the effect of temperature on the In As/Al Sb heterojunction and high-electron-mobility transistors（HEMTs） with a gate length of 2 μm are discussed comprehensively. The results indicate that device performance is greatly improved at cryogenic temperatures. It is also observed that the device performance at 90 K is significantly improved with 27% lower gate leakage current, 12% higher maximum drain current, and 22.5% higher peak transconductance compared to 300 K. The temperature dependence of mobility and the two-dimensional electron gas concentration in the In As/Al Sb heterojunction for the temperature range 90 K-300 K is also investigated. The electron mobility at 90 K（42560 cm2/V·s）is 2.5 times higher than its value at 300 K（16911 cm^2/V·s） because of the weaker lattice vibration and the impurity ionization at cryogenic temperatures, which corresponds to a reduced scattering rate and higher mobility. We also noted that the two-dimensional electron gas concentration decreases slightly from 1.99 × 10^（12） cm^（-2） at 300 K to 1.7 × 10^（12） cm^（-2） at 90 K with a decrease in temperature due to the lower ionization at cryogenic temperature and the nearly constant ？Ec.

关键词： temperature mobility two-dimensional electron gas InAs/AlSb HEMT

Structural Damage Law of Semiconductor Bridge Detonator under Impact and Overload Environment

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Journal of Beijing Institute of Technology 2020年第2期29卷 190-194页

作者： Dongxiao Fu Rui Zhang Hu Liu Fang Li Zhenhua Du hongliang Ma School of Electrical Engineering Xi’an Jiaotong UniversityXi’an 710049China State Key Laboratory of Applied Physics-Chemistry Shaanxi Applied Physics-Chemistry Research InstituteXi’an 710061China

Aiming to know the requirement of penetrating the munition semiconductor bridge detonator under the impact overload environment, the impact overload simulation device and the structural finite element software ANSYS/AUTODYN are used to study the variation of the axial dimension, charge and the chip gap of the semiconductor bridge detonator under the impact overload environment. The typical semiconductor bridge detonator is affected by the acceleration, and the strain increases with the increase of the acceleration. The semiconductor bridge detonator shows axial compression, in which the size becomes smaller, and the structural deformation occurs at the output end of the semiconductor bridge detonator. The typical semiconductor bridge detonator is elastically deformed when the acceleration is less than 40 000 g. When the acceleration is more than40 000 g, the semiconductor bridge detonator housing is plastically deformed. The gap between the drug column and the chip is divided into three stages with the increase of the acceleration. Initially,with the increase of the acceleration, the gap rises rapidly until the acceleration reaches 43 000 g,and when the gap reaches the maximum, the gap decreases rapidly with the increase of the acceleration. When the acceleration reaches 57 000 g, the gap tends to be 0 μm in the initial state, and then the gap does not change with the acceleration to keep tending to 0 μm.

关键词： impact overload semiconductor bridge detonator structural damage

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一种光学三维测量中的相位计算及补偿方法

机械工程学报 2005年第3期41卷 201-205页

作者：姜涛习俊通张鸿梁严隽琪上海交通大学计算机集成制造研究所上海200030

在基于格雷码和相移技术进行三维测量的过程中,相移光栅的非正弦性对测量精度有较大的影响。一般必须对获得的相位值进行修正以改进测量精度,常用的方法之一是物体相位传递函数,但其周期性假设使得修正结果仍然存在一定的误差。提出通... 详细信息

在基于格雷码和相移技术进行三维测量的过程中,相移光栅的非正弦性对测量精度有较大的影响。一般必须对获得的相位值进行修正以改进测量精度,常用的方法之一是物体相位传递函数,但其周期性假设使得修正结果仍然存在一定的误差。提出通过研究平面物体相位分布规律与标定相结合的方法。正确获得投影光栅在参考面的相位分布函数,降低光栅非正弦性的不利影响,消除物体相位传递函数周期性假设带来的误差,保证测量的精度和系统的健壮性。

关键词：格雷码相移三维测量非正弦

Microstructure and mechanical properties of C_(x)Hf_(0.25)NbTaW_(0.5) refractory high-entropy alloys at room and high temperatures

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Journal of Materials Science & Technology 2022年第2期97卷 229-238页

作者： Shiyu Wu Dongxu Qiao Haitao Zhang Junwei Miao hongliang Zhao Jun Wang Yiping Lu Tongmin Wang Tingju Li Key Laboratory of Solidification Control and Digital Preparation Technology(Liaoning Province) School of Materials Science and EngineeringDalian University of TechnologyDalian 116024China School of Materials Science and Engineering Zhengzhou UniversityZhengzhou 450001China State Key Laboratory of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China

The microstructure and mechanical properties of as-cast and isothermally annealed C_(x)Hf_(0.25)NbTaW_(0.5)(x=0,0.05,0.15,0.25)refractory high-entropy alloys(RHEAs)were *** the as-cast and annealed RHEAs consisted of disordered body-centered cubic solid solution phase and metal carbide(MC)phase with a face-centered cubic crystal structure(Fm-3 m space group).The primary carbides were enriched with Hf and C elements and tended to form lamellar eutectic-like microstructure in the *** lamellar eutectic-like structure in the interdendrites would be formed from the decomposition of sub-carbide M_(2)C under the influence of Hf *** isothermal annealing,slatted carbides were precipitated on the matrix,and the distribution became more uniform with high C *** formation of carbides strongly influenced the mechanical properties both at room and high *** yield strength values of C_(x)Hf_(0.25)NbTaW_(0.5) RHEA at 1473 and 1673 K were 792 and 749 MPa,*** result had exceeded the high temperature mechanical properties of currently known ***,this RHEA exhibited high-temperature performance stability and excellent plasticity,exceeding 30 and 50%at room and elevated temperatures(above 1273 K),*** thermal deformation,carbon-containing RHEAs obtained more severe work hardening than that of ACHO RHEAs,and required greater dynamic recrystallization to achieve the dynamic equilibrium.

关键词： Refractory high entropy alloys Mechanical properties Microstructure High temperature Carbon content