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Effects of thermomechanical treatments on the microstructures and mechanical properties of GTA-welded AZ31B magnesium alloy

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International Journal of Minerals,Metallurgy and Materials 2012年第10期19卷 945-950页

作者： Ya-jie Chu Jian Chen xiao-quan li Shen-qing WU Zong-hui Yang Department of Material Science and Engineering Jiangsu Key Laboratory for Advanced Metallic Materials South East University Nanjing 211189 china Department of Material Engineering Nanjing Institute of Technology Nanjing 211167 China

Thermomechanical treatments were carried out to improve the properties of AZ31B joints prepared by gas tungsten arc welding. The microstructures of the joints were studied by optical microscopy and scanning electron microscopy with energy-dispersive spectrometry. Tensile tests and hardness tests were performed to investigate the effects of thermomechanical treatments on the mechanical properties of the joints. It is found that the thermomechanical-treated joints show superior mechanical properties against the as-welded joints, and their ultimate tensile strength can reach more than 92% of the base material. This mainly attributes to the formation of fine equiaxed grains in the fusion zone. ARer thermomechanical treatments the dendrites are transformed to fine spherical grains, and the dendritic segregation can be effectively eliminated.

关键词： magnesium alloys welding microstructure mechanical properties fractography

梅毒螺旋体抗体最佳S/CO截断值在梅毒筛查中的应用价值

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实用中西医结合临床 2024年第10期24卷 1-5页

作者：王靖李小全刘敏杨志立徐植赵雅淳王丽河南大学第一附属医院开封475000

目的以梅毒螺旋体凝集试验(TPPA)作为确认试验,确立酶联免疫吸附试验(EliSA)法S/CO值与梅毒阳性最佳截断值,减少不必要的TPPA确认重复。方法选取2022年10月至2023年10月在医院进行梅毒螺旋体(TP)抗体检测的血清标本22 500例,以EliSA... 详细信息

目的以梅毒螺旋体凝集试验(TPPA)作为确认试验,确立酶联免疫吸附试验(EliSA)法S/CO值与梅毒阳性最佳截断值,减少不必要的TPPA确认重复。方法选取2022年10月至2023年10月在医院进行梅毒螺旋体(TP)抗体检测的血清标本22 500例,以EliSA法为梅毒初次筛查试验,采用TPPA和甲苯胺红不加热血清试验(TRUST)对所有反应结果进行复核和确认。分析376例有反应性标本中的S/CO值与TPPA的关系,使用受试者操作特征曲线(ROC)确定EliSA法S/CO值与TPPA阳性最佳截断值。根据S/CO最佳截断值,比较梅毒不同反式筛查策略需要TPPA确认的标本数量。结果当S/CO≥6.6时,TPPA与EliSA结果一致,特异性和阳性预测值均为100.00%,S/CO=6.6时为最佳截断值;使用欧洲疾病预防与控制中心(ECDC)策略时,376例筛查反应性样本(100.00%,376/376)需TPPA确认;使用美国疾病控制与预防中心(CDC)策略时,TPPA还需确认217例(57.71%,217/376);本研究只有122例(32.45%,122/376)需进行TPPA确认。结论采用EliSA法梅毒反式筛查策略不受TRUST结果影响,当S/CO≥6.6时不需要进行TPPA确认,与ECDC和CDC反式策略相比,本研究有67.55%的筛查反应样本不必进行TPPA确认,经济且节约时间和人力。

关键词：梅毒 S/CO值最佳截断值 TPPA

Analysis on characteristics of 1-D apodized and chirped photonic crystals containing negative refractive materials

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Optoelectronics Letters 2008年第6期4卷 440-442页

作者： TONG Kai CUI Wei-wei XU xiao-hui li Zhi-quan College of Electric Engineering University of Yanshan Qinhuangdao 066004China

Using transfer matrix method,the optical transmission properties of 1-D photonic crystals composed partially of negative refraction media are analyzed. The transmission spectra of periodic photonic crystal,chirped photonic crystal and apodized photonic crystal are numerically simulated respectively. By contrast with optical transmission properties of ordinary photo-nic crystals made of positive refraction media,the transmission spectra of apodized photonic crystal become unregular,the Bragg flat-headed area recurs but the peak of transmission does not change significantly. Futhermore,the band gap range of chirped photonic crystal diminishes gradually.

关键词：连续变频信号光子晶体折射材料晶体特征

Sliced Average Variance Estimation for Tensor Data

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Acta Mathematicae Applicatae Sinica 2024年第3期40卷 630-655页

作者： Chuan-quan li Pei-wen xiao Chao YING xiao-hui liU School of Statistics Jiangxi University of Finance and EconomicsNanchang 330013China Key Laboratory of Data Science in Finance and Economics Jiangxi University of Finance and EconomicsNanchang 330013China Biostatistics and Medical Informatics University of Wisconsin MadisonMadison 53726USA

Tensor data have been widely used in many fields,e.g.,modern biomedical imaging,chemometrics,and economics,but often suffer from some common issues as in high dimensional *** to find their low-dimensional latent structure has been of great interest for *** this end,we develop two efficient tensor sufficient dimension reduction methods based on the sliced average variance estimation(SAVE)to estimate the corresponding dimension reduction *** first one,entitled tensor sliced average variance estimation(TSAVE),works well when the response is discrete or takes finite values,but is not■consistent for continuous response;the second one,named bias-correction tensor sliced average variance estimation(CTSAVE),is a de-biased version of the TSAVE *** asymptotic properties of both methods are derived under mild *** and real data examples are also provided to show the superiority of the efficiency of the developed methods.

关键词： tensor data sliced average variance estimation sufficient dimension reduction central subspace

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面向芯粒间互连的低功耗发射机驱动设计

计算机工程与科学 2024年第4期46卷 599-605页

作者：任博琳肖立权齐星云张庚王强罗章庞征斌徐佳庆国防科技大学计算机学院湖南长沙410073

面向UCIe协议提出的芯粒间互连标准,设计与实验了一种面向芯粒(Chiplet)间互连的低功耗发射机驱动。该驱动电路采用了SST电压模驱动器,功耗仅为CML电流模驱动器结构的1/4。此外,该驱动电路基于可调前馈均衡技术,针对不同的信道衰减调整... 详细信息

面向UCIe协议提出的芯粒间互连标准,设计与实验了一种面向芯粒(Chiplet)间互连的低功耗发射机驱动。该驱动电路采用了SST电压模驱动器,功耗仅为CML电流模驱动器结构的1/4。此外,该驱动电路基于可调前馈均衡技术,针对不同的信道衰减调整均衡强度,采用去加重均衡的方式提高发射信号质量,最终降低码间干扰。本文设计采用CMOS 28 nm工艺设计,前端仿真结果表明,在0.9 V电压供电时,最大均衡强度为-3.7 dB,当32 Gbps的NRZ信号通过21 mm的信道时(16 GHz奈奎斯特频率处衰减为-2.37 dB),选择合适均衡强度后,输出波形眼图眼高为253 mV(71.8%),眼宽为27 ps(87%),仿真功耗仅为4.0 mW。

关键词：芯粒前馈均衡器 SST驱动器高速接口电路发射机

Reference genes for quantitative real-time PCR analysis and quantitative expression of P5CS in Agropyron mongolicum under drought stress

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Journal of Integrative Agriculture 2016年第9期15卷 2097-2104页

作者： TIAN Qing-song WANG Shu-yan DU Jian-cai WU Zhi-juan li xiao-quan HAN Bing Institute of Grassland Research Chinese Academy of Agricultural Sciences Hohhot 010010 P.R. China gronomy College Inner Mongolia Agricultural University Hohhot 010010 P.R. China College of life Science Inner Mongolia Agricultural University Hohhot 010010 P.R. China

Reference genes, stably expressing in different tissues and cells, are commonly used as the references in expression analysis. Selecting the optimum reference gene is crucial to the success of experiments. In this study, the expression stabilities of nine common reference genes, including ACT2, 18 S r RNA, APRT, EF-1α, RNA POL II, TUBα, TUBβ, GAPDH and TLF of Agropyron mongolicum, were studied under drought condition. Among them, 18 S r RNA was found to be the most optimum reference gene under drought stress by the analyzing of ge Norm and Norm Finder software. quantitative expression levels of P5 CS using 18 S r RNA as the reference gene, and proline contents under drought stress in A. mongolicum were further operated, and we found the expression level of P5 CS gene and proline content had a significantly positive relationship（R^2=0.7763, P〈0.05）. This study established and validated 18 S r RNA as the reference genes in A. mongolicum under drought stress, providing a powerful tool for the quantitative expression analysis of drought genes in A. mongolicum.

关键词： reference genes quantitative real-time PCR drought stress proline pyrroline-5-carboxylic acid synthetase Agropyron mongolicum

Transient liquid phase diffusion bonding of copper alloy to stainless steel using CuMn alloys as interlayer

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中国有色金属学会会刊：英文版 2000年第3期10卷 349-352页

作者： YU Zhi shui(于治水) WANG Feng jiang(王凤江) li xiao quan(李晓泉) WANG Yu(王宇) WU Ming fang(吴铭方) E China Shipbldg Inst Dept Mat Engn Zhenjiang 212003 Peoples R China

With CuMn alloy as interlayer, the transient liquid phase (TLP) diffusion bonding of Cu alloys (CuAlBe) to stainless steel (1Cr18Ni9Ti) was studied. The results show that the bonding pressure, time and temperature and the content of Mn in CuMn alloy have great effects on the strength of bonding interface; when they are 1 MPa, 40 min, 1 223 K and 30% respectively, the maximum joint strength of 487 MPa is attained. The fracture occurring at the bonding interface is a plastic one and the effect of Mn has been analyzed.

关键词： copper alloys stainless steels diffusion bonding CuMn alloys

Virtual and physical address translation mechanism of interconnect network

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Journal of Beijing Institute of Technology 2016年第3期25卷 365-374页

作者： li Tie-jun ZHANG Jian-min MA Ke-fan xiao li-quan li Si-kun School of Computer National University of Defense Technology Changsha 410073 China

Most of users are accustomed to utilizing virtual address in their parallel programs running at the scalable high-performance parallel computing *** a virtual and physical address translation mechanism is necessary and crucial to bridge the hardware interface and software *** this paper,a new virtual and physical translation mechanism is proposed,which includes an address validity checker,an address translation cache（ATC）,a complete refresh scheme and many reliability *** ATC employs a large capacity embedded dynamic random access memory（eDRAM）to meet the high hit ratio *** also can switch the cache and buffer mode to avoid the high latency of accessing the main memory *** tests have been conducted on the real chip,which implements the address translation *** results show that the ATC has a high hit ratio while running the well-known benchmarks,and additionally demonstrates that the new high-performance mechanism is well designed.

关键词： interconnect network virtual address physical address cache

Achieving high carrier mobility and low lattice thermal conductivity in GeTe-based alloys by cationic/anionic co-doping

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Rare Metals 2024年第6期43卷 2784-2795页

作者： xiao-Qiang Wang xiao-quan Hu Jun-Yan lin Chu-Bin li xiao-Tong Yu Qi-Yong Chen li-li Xi Qi-Shuo Yang Han li Ji-Ye Zhang Shuan-Kui li Kai Guo School of Physics and Materials Science Guangzhou UniversityGuangzhou 510006China Research Center for Advanced Information Materials(CAIM) Huangpu Research&Graduate School of Guangzhou UniversitySino-Singapore Guangzhou Knowledge CityGuangzhou510555China School of Materials Science and Engineering Shanghai UniversityShanghai 200444China Materials Genome Institute Shanghai UniversityShanghai 200444China School of Mechanical and Mining Engineering University of QueenslandBrisbaneQLD 4072Australia Key Laboratory of Si-Based Information Materials&Devices and Integrated Circuits Design Department of Education of Guangdong ProvinceGuangzhou 510006China

TheⅣ-Ⅵcompound GeTe is considered as a promising alternative to the toxic PbTe for high-efficiency mid-temperature thermoelectric ***,pristine GeTe suffers from a high concentration of Ge vacancies,resulting in an excessively high hole concentration(>1×10^(21)cm^(-3)),which greatly limits its thermoelectric *** address this issue,CuBiTe_(2)alloying is introduced to increase the formation energy of Ge vacancies in GeTe,thereby inhibiting the high carrier *** carrier scattering caused by the electronegativity difference between different elements is suppressed due to the similar electronegativity of Cu and Ge atoms.A relatively high hole mobility is obtained,which ultimately leads to a high power ***,by introducing Se as an alloying element at the anionic site in GeTe,dense point defects with mass/strainfield fluctuations are *** contributes to the strengthening of phonon scattering,thereby reducing the lattice thermal conductivity from 1.44 W·m^(-1)·K^(-1)for pristine GeTe to 0.28 W·m^(-1)·K^(-1)for Ge_(0.95)Cu_(0.05)Bi_(0.05)Te_(0.9)Se_(0.15)compound at 623 K.

关键词： GeTe Carrier mobility CuBiTe_(2)alloying Lattice thermal conductivity Thermoelectric properties