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Microstructure and mechanical behavior of a low-density Fe-12Mn- 9Al-1.2C steel prepared using centrifugal casting under near-rapid solidification

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Journal of Iron and Steel Research International 2018年第8期25卷 830-838页

作者： Wei He Bi-lei Wang Yang Yang Yun-hu Zhang Lian Duan zhi-ping luo Chang-jiang Song Qi-jie Zhai State Key Laboratory of Advanced Special Steel Shanghai Key Laboratory of Advanced Ferrometallurgy School of Materials Science and Engineering Shanghai UniversityShanghai 200444 China Department of Chemistry and Physics Fayetteville State University Fayetteville NC 28301 USA

It is vital for emission reduction and energy saving to lighten the weight of automobile. Low-density Fe-Mn-Al-C steels with high strength and excellent ductility have become a promising type of material in the automotive industry. Thus, a new approach was proposed by using centrifugal casting to produce the low-density Fe-12Mn-9Al-1.2C steel with high performance under near-rapid solidification in a near-net shape. The produced steel strips, with a thickness of 2.5 mm and a density of 6.89 g/cm3, were examined for their microstructures and mechanical properties. The results showed that mechanical properties of as-cast steel strip reached 1182 MPa in ultimate tensile strength and 28.1% in total elongation. Aging treatment at 400 or 600℃ for 3 h enhanced tensile strength of the steel strips, while aging at 800℃ dramatically decreased its elongation. Moreover, Young＇ s modulus of the steel strip improved with the increment of aging temperature. The relationship between the mechanical properties and the microstructures was discussed. The results demonstrated that advanced low-density steels with promising mechanical properties could be directly produced from liquid by this simple process.

关键词： Low-density steel Near-net shape Mechanical property Microstructure Near-rapid solidification

Development of alpha surface contamination monitor based on THGEM for contamination distribution

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Nuclear Science and Techniques 2019年第10期30卷 48-54页

作者： Si-Min Xiao zhi-ping luo Qian Liu Guo-Jun Yuan Hong-Chao Pang Yang Liu Jin-Feng Huang Shi Chen China Institute of Atomic Energy Beijing 100049China University of Chinese Academy of Sciences Beijing 100049China CAS Key Laboratory of Vacuum Physics UCASBeijing 100049China

In cases of high radiation emergencies,we propose a surface contamination monitor(SCM)that can quickly measure and pinpoint the contamination distribution in the affected *** gaseous electron multiplier(THGEM)has several advantages,including fast response time and good spatial *** on new THGEMs,a two-dimensional imaging detector was developed for alpha detection,with a position resolution greater than 3 *** detector design and test results are described in this *** radiation imaging SCMs,with a 40mm×40 mm sensitive area,are currently under development.

关键词： THGEM detector Surface contamination distribution Alpha particle Position resolution Imaging detector

Crystal structure and formation mechanism of the secondary phase in Heusler Ni-Mn-Sn-Co materials

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Advances in Manufacturing 2014年第4期2卷 353-357页

作者： Jin-Ke Yu Hong-Wei Li Qi-Jie Zhai Jian-Xun Fu zhi-ping luo Hong-Xing Zheng Laboratory for Microstructures Shanghai University Shanghai Key Laboratory of Modern Metallurgy and Materials Processing Shanghai University Department of Chemistry and Physics Fayetteville State University

In the present work, crystal structure and for- mation mechanism of the secondary phase in Heusler Ni- Mn-Sn-Co materials were investigated using X-ray dif- fraction, scanning/transmission electron microscopy and selected-area electron diffraction techniques. Experimental results showed that the secondary phase presented in both Ni44.1Mn35.1Sn10.8Co10 as-cast bulk alloy and melt-spun ribbon, possessing a face-centered cubic （fcc） NilTSn3-type structure. The secondary phase in the as-cast bulk alloy was resulted from a eutectic reaction after the formation of a primary dendritic flphase during cooling. However in the melt-spun rapidly solidified ribbon, the secondary phase was largely suppressed as nano-precipitates distributed along the grain boundaries, which was attributed to a divorced eutectic reaction. The secondary phase exhibited partial amorphous state due to high local cooling rate.

关键词： Heusler Ni-Mn-Sn-Co materials Secondaryphase Melt spinning Divorced eutectic reaction Microstructure

Interfacial microstructure and mechanical properties of diffusion-bonded joints of titanium TC4 (Ti-6Al-4V) and Kovar (Fe-29Ni-17Co) alloys

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Journal of Iron and Steel Research International 2017年第10期24卷 1023-1031页

作者： Ting-feng Song Xiao-song Jiang Zhen-yi Shao De-feng Mo De-gui Zhu Min-hao Zhu Christina H.Young zhi-ping luo School of Materials Science and Engineering Southwest Jiaotong University Department of Material Engineering Chengdu Technological University Key Laboratory of Infrared Imaging Materials and Detectors Shanghai Institute of Technical PhysicsChinese Academy of Sciences Department of Chemistry and Physics Fayetteville State University

Diffusion bonding is a near net shape forming process that can join dissimilar materials through atomic diffusion under a high pressure at a high *** alloy TC4（Ti-6 Al-4 V）and 4 J29 Kovar alloy（Fe-29 Ni-17 Co）were diffusely bonded by a vacuum hot-press sintering process in the temperature range of 700-850°C and bonding time of 120 min,under a pressure of 34.66 *** microstructures and intermetallic compounds of the diffusion-bonded joints were characterized by optical microscopy,scanning electron microscopy,X-ray diffraction（XRD）and energy dispersive spectroscopy（EDS）.The elemental diffusion across the interface was revealed by electron probe *** properties of joints were investigated by micro Vickers hardness and tensile *** of EDS and XRD indicated that（Fe,Co,Ni）-Ti,TiNi,Ti_2Ni,TiNi_2,Fe_2 Ti,Ti_（17） Mn_3 and Al_6 Ti_（19） were formed at the *** the bonding temperature was raised from 700 to 850°C,the voids of interface were reduced and intermetallic layers were *** tensile strength of joints at 53.5 MPa was recorded by the sintering process at 850°C for 120 *** surface of the joint indicated brittle nature,and failure took place through interface of intermetallic *** on the mechanical properties and microstructure of the diffusion-bonded joints,diffusion mechanisms between Ti-6 Al-4 Vtitanium and Fe-29 Ni-17 Co Kovar alloys were analyzed in terms of elemental diffusion,nucleation and growth of grains,plastic deformation and formation of intermetallic compounds near the interface.

关键词： Titanium alloy Kovar alloy Diffusion-bonded joint Microstructure Mechanical property

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高速铁路桥隧过渡段钢轨温度和纵向变形试验

铁道工程学报 2017年第1期34卷 30-35页

作者：曾志平罗俊魏炜宋善义中南大学长沙410075

研究目的:为得到高速铁路过渡段处钢轨温度沿纵向分布规律以及钢轨纵向位移变化特征,以合福高铁某桥隧过渡段为研究对象,对钢轨温度和纵向变形进行连续监测,以期为过渡段处无缝线路的稳定性研究提供参考。研究结论:(1)隧道洞口20 m范围... 详细信息

研究目的:为得到高速铁路过渡段处钢轨温度沿纵向分布规律以及钢轨纵向位移变化特征,以合福高铁某桥隧过渡段为研究对象,对钢轨温度和纵向变形进行连续监测,以期为过渡段处无缝线路的稳定性研究提供参考。研究结论:(1)隧道洞口20 m范围内将形成轨温过渡段,局部最大温度梯度可达6.9℃/m,远大于温度梯度按线性分布计算所得的1.55℃/m;(2)过渡段处钢轨随着日温差的变化,其纵向位移变化显著,最大日轨温差为34.9℃,最大日变化量为1.6 mm;(3)过渡段处钢轨纵向位移呈现由桥梁向着隧道方向线性累积增加的趋势,最大累积变形量为2 mm;通车后累积变形速率为0.016 9 mm/d,大于通车前的0.014 7 mm/d;(4)基于最小二乘法建立了轨温过渡段钢轨温度沿线分布模式,以及钢轨日温差与钢轨纵向位移日变化量预估模型,得出:拟合精度较高,回归模型可靠;(5)本研究结论可为高速铁路无砟轨道桥隧过渡段钢轨温度力和纵向爬行提供研究基础。

关键词：过渡段钢轨温度纵向变形试验

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桥隧过渡段轨温与钢轨纵向位移的映射关系

铁道工程学报 2018年第1期35卷 29-35,61页

作者：曾志平罗俊饶惠明吴志鹏中南大学长沙410075 京福闽赣铁路客运专线有限公司福州350013

研究目的:桥隧过渡段处钢轨在梯度温度力作用下将发生纵向爬行,影响无缝线路稳定性。本文以轨温过渡区钢轨为研究对象,建立钢轨位移微分方程,推导轨温分布与钢轨纵向位移的映射关系,从而揭示影响无砟轨道钢轨爬行的规律。研究结论:(1)... 详细信息

研究目的:桥隧过渡段处钢轨在梯度温度力作用下将发生纵向爬行,影响无缝线路稳定性。本文以轨温过渡区钢轨为研究对象,建立钢轨位移微分方程,推导轨温分布与钢轨纵向位移的映射关系,从而揭示影响无砟轨道钢轨爬行的规律。研究结论:(1)考虑扣件阻力非线性的钢轨纵向位移量和变形范围均远大于线性阻力模型;对钢轨最大位移量而言,轨温非线性分布相较于线性分布高出5.3%～38.6%,建议同时考虑轨温和纵向阻力非线性以准确获得过渡段钢轨爬行位移;(2)轨温差一定时,随着最大温度力梯度倍数k从1.5变化至3.5,轨温过渡区长度为10 m时,钢轨最大纵向位移增加了7%,而过渡区长度为40 m和50 m时分别增加了26.7%和32.8%,因此对于轨温差大、轨温过渡区长的过渡段,更应关注轨温非线性分布;(3)扣件极限阻力增大将使钢轨爬行量显著降低,但影响程度有限,极限阻力从6.5 kN/(m·轨)增加至12 kN/(m·轨),钢轨位移量下降40.8%～49.2%,而从24 kN/(m·轨)增加至30 kN/(m·轨),仅下降12.8%～24.4%;(4)推导的解析表达式能够准确描述各参数与钢轨纵向位移的映射关系,对于进一步研究过渡段钢轨受力特性以及改善无缝线路稳定性具有参考价值。

关键词：过渡段无砟轨道无缝线路钢轨爬行映射关系

Social function scores and influencing factors in patients with residual depressive symptoms

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World Journal of Psychiatry 2025年第1期15卷 117-127页

作者： Zong-Ling Liao Xiao-Li Pu zhi-Yi Zheng Jie luo Department 1 of Psychiatry Gele Mountain Hospital of Chongqing Mental Health CenterChongqing 400030China Department of Psychology Chongqing Jiangjin District Psychiatric HospitalChongqing 402260China Department of Psychiatry Chongqing Third Social Welfare InstituteChongqing 400036China Women and Children’s Mental Health Center Affiliated Hospital of Chongqing Population and Family Planning Research InstituteChongqing 400020China

BACKGROUND At present,the influencing factors of social function in patients with residual depressive symptoms are still *** depressive symptoms are highly harmful,leading to low mood in patients,affecting work and interpersonal communication,increasing the risk of recurrence,and adding to the burden on *** the influencing factors of their social function is of great *** To explore the social function score and its influencing factors in patients with residual depressive *** This observational study surveyed patients with residual depressive symptoms(case group)and healthy patients undergoing physical examinations(control group).Participants were admitted between January 2022 and December *** functioning was assessed using the Sheehan Disability Scale(SDS),and scores were compared between *** influencing SDS scores in patients with residual depressive symptoms were analyzed by applying multiple linear regression while using the receiver operating characteristic curve,and these RESULTS The SDS scores of the 158 patients with depressive symptoms were 11.48±*** with the control group,the SDS scores and all items in the case group were *** scores were higher in patients with relapse,discon-tinuous medication,drug therapy alone,severe somatic symptoms,obvious residual symptoms,and anxiety scores≥*** history,medication compliance,therapy method,and residual symptoms correlated positively with SDS scores(r=0.354,0.414,0.602,and 0.456,respectively).Independent influencing factors included disease history,medication compliance,therapy method,somatic symptoms,residual symptoms,and anxiety scores(P<0.05).The areas under the curve for predicting social functional impairment using these factors were 0.713,0.559,0.684,0.729,0.668,and 0.628,respectively,with sensitivities of 79.2%,61.8%,76.8%,81.7%,63.6%,and 65.5%and specificities of 83.3%,87.5%,82.6%,83.3%,86.7%,and 92.1%,respectively.C

关键词： Depressive Residual symptoms Social function Influence factors

Exploring practical methods for detecting k-nonseparability in multipartite quantum states

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Science China(Physics,Mechanics & Astronomy) 2025年第1期Mechanics & Astronomy) .卷 255-256页

作者： Shunlong luo Academy of Mathematics and Systems Science Chinese Academy of Sciences

Quantum entanglement, referred to as “spooky action at a distance” by Einstein, is not only an intriguing and fascinating feature of quantum theory challenging our classical intuitions about locality and correlations, but also has practical and profound implications for quantum technologies. Initially described by Einstein, Podolsky and Rosen, as well as by Schro¨dinger, entanglement now has become a basic and crucial ingredient for both foundational and experimental investigations of the quantum world.

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In situ polymerization of poly(3,4-ethylenedioxythiophene)protective layer towards stable zinc anode

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Nano Research 2025年第1期18卷 382-394页

作者： Debin luo Peng Zhou Xiaowei Lv Panpan Sun Xiaohua Sun Hewei Zhao College of Materials and Chemical Engineering Key Laboratory of Inorganic Nonmetallic Crystalline and Energy Conversion MaterialsChina Three Gorges UniversityYichang 443002China Hubei Three Gorges Laboratory Yichang 443007China School of Chemistry Beihang UniversityBeijing 100191China

Aqueous zinc-ion devices are considered promising candidates for energy storage due to their high safety,low cost and relatively high energy ***,the dendrite growth,hydrogen evolution reaction(HER)and corrosion of the zinc anode significantly limit the development of Zn-ion ***,an inexpensive poly(3,4-ethylenedioxythiophene)(PEDOT)protective layer was constructed in situ on the Zn surface using electropolymerization to suppress dendrite growth and side reactions,thereby enhancing the reversibility of *** and theoretical calculations revealed that this hydrophilic protective layer promotes the desolvation process of hydrated Zn^(2+)and facilitates the transport of zinc ions,thus improving the thermodynamic and kinetic properties of Zn^(2+)deposition and inhibiting interfacial side ***,the optimized PEDOT@Zn symmetric battery exhibited a cycling stability exceeding 1250 h at 0.5 mA·cm^(-2)and 0.25 mAh·cm^(-2),with a significantly reduced overpotential(from 91.8 to 35 mV).With the assistance of the PEDOT protective layer,the PEDOT@Zn//Cu battery maintained approximately 99.5%Coulombic efficiency after 450 ***-situ scanning electron microscopy(SEM)and in situ optical microscopy characterizations further confirmed that the PEDOT protective layer can effectively suppress the growth of zinc ***,the Zn-ion capacitors assembled by the PEDOT@Zn and activated carbon also demonstrated outstanding cycling stability.

关键词： zinc-ion devices zinc anode poly(3 4-ethylenedioxythiophene)(PEDOT) dendrite desolvation process