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基于矢量衍射理论的光栅干涉仪位移测量误差研究

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红外与激光工程 2024年第2期53卷 90-97页

作者：雷李华张玉杰傅云霞上海市计量测试技术研究院上海201203 上海市在线检测与控制技术重点实验室上海201203

光栅干涉仪位移测量系统作为测量领域中最精密的测量仪器之一,由于在测量过程中光栅的姿态位置无法保证完美装配,使得光栅的光栅矢量方向与运动矢量方向之间出现偏差,导致位移测量结果出现周期性非线性误差。文中针对在光栅干涉仪位移... 详细信息

光栅干涉仪位移测量系统作为测量领域中最精密的测量仪器之一,由于在测量过程中光栅的姿态位置无法保证完美装配,使得光栅的光栅矢量方向与运动矢量方向之间出现偏差,导致位移测量结果出现周期性非线性误差。文中针对在光栅干涉仪位移测量过程中出现的光栅与位移台以及读数头之间的姿态位置误差进行分析,通过分别建立位移坐标系及光栅坐标系,参考惯性导航领域中飞行器姿态表示方法,利用一维光栅的横滚、俯仰和偏航角共同描述一维光栅相对于位移台的装配状态。通过基于矢量衍射理论分析光栅干涉仪位移测量时三个维度的角度偏差量,对可能产生的位移测量误差进行了分析说明。基于广义一维光栅方程,探究出了一个更为普遍的结论,为后续装置的改进提供理论依据,以提高系统的测量精度。

关键词：精密位移测量光栅干涉仪光栅矢量衍射周期性误差

Ultrasonic-based surface patterning and interfacial reaction of zrO_(2)ceramics

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Journal of Materials Science & Technology 2023年第24期155卷 202-210页

作者： H.J. Dong z.L. Li X.G.Song J.C. Feng S.J. Wei J.H. fu Y. Shi State Key Laboratory of Advanced Welding and Joining Harbin Institute of Technology Harbin 150001 China Shandong Provincial Key Lab of Special Welding Technology Harbin Institute of Technology at Weihai Weihai 264209 China

We demonstrate a process to achieve selective surface metallization of zrO_(2)ceramics using ultrasound technology in atmospheric environments at 350℃,which bestows good weldability of zrO_(2)to achieve rapid and reliable connections with other metals as well as ceramic *** challenge is that brazing or diffusion welding processes to accomplish metallurgical connections for zrO_(2) typically require holding at elevated temperatures for minutes to hours,while the selective ultrasonic metallization process requires only a few seconds of processing without the application of covering films or solder *** this study,the selected Sn-2Ti alloy could effectively wet and spread on zrO_(2)substrate under ultrasonication,and continuous interphase layers were rapidly formed in situ between zrO_(2)and *** bonding strength for the zrO_(2)/Sn-2Ti interface was well established with the highest shear strength of 37.1 MPa,and the fracture location occurred at the filler *** interfacial reaction layer thickened remarkably with the prolongation of sonication,accompanied by the partial crystallization of amorphous TiO and the formation of irregularly striped Ti_(11.31)Sn_(3)O_(10)nanocrystals.

关键词： Selective ultrasonic metallization zirconia surface patterning Low temperature connection Sono-oxidation Interfacial reaction

Microstructure and Mechanical Property of Hot-Rolled Mg-2Ag Alloy Prepared with Multi-pass Rolling

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Acta Metallurgica Sinica(English Letters) 2023年第2期36卷 335-342页

作者： H.zhang H.L.Hao G.Y.fu B.S.Liu R.G.Li R.z.Wu H.C.Pan School of Mechanical and Power Engineering Shenyang University of Chemical TechnologyShenyang110142China Key Laboratory of Superlight Materials and Surface Technology Ministry of EducationCollege of Materials Science and Chemical EngineeringHarbin Engineering UniversityHarbin150001China Key Laboratory for Anisotropy and Texture of Materials(Ministry of Education) Northeastern UniversityShenyang110819China

A conventional multi-pass rolling is designed to form different microstructures in a Mg-2Ag *** relationship between microstructure and mechanical property is *** result shows that twin-induced nucleation plays a prominent role for the dynamic recrystallization(DRX)behavior of the rolled Mg-2Ag *** DRXed grains distributed around elongated grains have random orientations but gradually turn to the concentrated orientation with strong basal texture when the rolling pass *** yield strength and ultimate tensile strength of rolled Mg-2Ag alloy gradually increase with increasing rolling *** elongation of rolled sample is gradually improved when the rolling pass increases from one to three,while a significant drop of elongation shows in the four-pass rolling *** strong basal texture,refined grains,high-density dislocations,and Ag segregation along grain boundaries are suggested to play a prominent role for enhancing the strength of Mg-Ag alloys,while the low-density dislocations,homogeneously fine-grained microstructure,and weak texture are critical for improving the ductility.

关键词： Magnesium alloy Conventional rolling Twinning Dynamic recrystallization Texture

Effects of COL1A1 and SYTL2 on inflammatory cell infiltration and poor extracellular matrix remodeling of the vascular wall in thoracic aortic aneurysm

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Chinese Medical Journal 2024年第9期137卷 1105-1114页

作者： Xinsheng Xie Ye Yuan Yulong Huang Xiang Hong Shichai Hong Gang Chen Yihui Chen Yue Lin Weifeng Lu Weiguo fu Lixin Wang Department of Vascular Surgery Zhongshan Hospital(Xiamen)Fudan UniversityXiamenFujian 361015China Department of Vascular Surgery Zhongshan HospitalFudan UniversityShanghai 200032China Vascular Surgery Institute of fudan University Fudan UniversityShanghai 200032China

Background:Thoracic aortic aneurysm(TAA)is a fatal cardiovascular disease,the pathogenesis of which has not yet been *** study aimed to identify and validate the diagnostic markers of TAA to provide a strong theoretical basis for developing new methods to prevent and treat this ***:Gene expression profiles of the GSE9106,GSE26155,and GSE155468 datasets were acquired from the Gene Expression Omnibus(GEO)*** expressed genes(DEGs)were identified using the"limma"package in *** absolute shrinkage and selection operator(LASSO),support vector machine-recursive feature elimination(SVM-RFE),random forest,and binary logistic regression analyses were used to screen the diagnostic marker ***-sample gene set enrichment analysis(ssGSEA)was used to estimate immune cell infiltration in ***:A total of 16 DEGs were *** enrichment and functional correlation analyses showed that DEGs were mainly associated with inflammatory response pathways and collagen-related *** type I alpha 1 chain(COL1A1)and synaptotagmin like 2(SYTL2)were identified as diagnostic marker genes with a high diagnostic value for *** expression of COL1A1 and SYTL2 was considerably higher in TAA vascular wall tissues than in the corresponding normal tissues,and there were significant differences in the infiltration of immune cells between TAA and normal vascular wall ***,COL1A1 and SYTL2 expression were associated with the infiltration of immune cells in the vascular wall ***-cell analysis showed that COL1A1 in TAA was mainly derived from fibroblasts and SYTL2 mainly from cluster of differentiation(CD)8+T *** addition,single-cell analysis indicated that fibroblasts and CD8+T cells in TAA were significantly higher than those in normal arterial wall ***:COL1A1 and SYTL2 may serve as diagnostic marker genes for *** upregulation of SYTL2 and COL1A1 may be involved in the inflammat

关键词： Bioinformatics Thoracic aortic aneurysm Immune response Single cell analysis Machine learning

New ductile laminate structure of Ti-alloy/Ti-based metallic glass composite with high specific strength

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Journal of Materials Science & Technology 2018年第4期34卷 708-712页

作者： D.Li z.W.zhu A.M.Wang H.M.fu H.Li H.W.zhang H.F.zhang Shenyang National Laboratory for Materials Science Institute of Metal Research Chinese Academy of Sciences

Bulk laminate structure of Ti-alloy/Ti-based metallic glass composite （MGC） was prepared by melting a preform of alternate stack-up foils in the high vacuum atmosphere. The composite demonstrates a good combination of yield strength （-1618MPa）, plasticity （-4.3%） and specific fracture strength （384 × 10^3 N m kg^-1 ） in compression. The maintained yield strength results from the unique microstruc- ture composed of the Ti layer, the solution layer with gradient structure and the MGC layer. Such a multilayer structure effectively inhibits the propagation of shear band, leading to the enhanced plastic- ity. Those extraordinary properities suggest that combining ductile lamella with brittle metallic glass （MG） by such a lay-up method can be an effective way to improve mechanical properties of MG.

关键词： Laminate composite Metallic glass Specific strength Plasticity

Variational Corner Transfer Matrix Renormalization Group Method for Classical Statistical Models

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Chinese Physics Letters 2022年第6期39卷 65-70页

作者： X.F.Liu Y.F.fu W.Q.Yu J.F.Yu z.Y.Xie Department of Physics Renmin University of ChinaBeijing 100872China School of Physics and Electronics Hunan UniversityChangsha 410082China

In the context of tensor network states,we for the first time reformulate the corner transfer matrix renormalization group(CTMRG)method into a variational bilevel optimization *** solution of the optimization problem corresponds to the fixed-point environment pursued in the conventional CTMRG method,from which the partition function of a classical statistical model,represented by an infinite tensor network,can be efficiently *** validity of this variational idea is demonstrated by the high-precision calculation of the residual entropy of the dimer model,and is further verified by investigating several typical phase transitions in classical spin models,where the obtained critical points and critical exponents all agree with the best known results in *** extension to three-dimensional tensor networks or quantum lattice models is straightforward,as also discussed briefly.

关键词： tensor variational straight

Quintom cosmology and modified gravity after DESI 2024

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Science Bulletin 2024年第17期69卷 2698-2704页

作者： Yuhang Yang Xin Ren Qingqing Wang zhiyu Lu Dongdong zhang Yi-fu Cai Emmanuel N.Saridakis Department of Astronomy School of Physical SciencesUniversity of Science and Technology of ChinaHefei 230026China CAS Key Laboratory for Researches in Galaxies and Cosmology School of Astronomy and Space ScienceUniversity of Science and Technology of ChinaHefei 230026China Deep Space Exploration Laboratory Hefei 230088China Department of Physics Tokyo Institute of TechnologyTokyo 152-8551Japan Kavli IPMU(WPI) UTIASThe University of TokyoChiba 277-8583Japan National Observatory of Athens Lofos Nymfon 11852Greece Departamento de Matemáticas Universidad Católica del NorteAntofagasta 1270398Chile

We reconstruct the cosmological background evolution under the scenario of dynamical dark energy through the Gaussian process approach,using the latest Dark Energy Spectroscopic Instrument(DESI)baryon acoustic oscillations(BAO)combined with other *** results reveal that the reconstructed dark-energy equation-of-state(EoS)parameter w(z)exhibits the so-called quintom-B behavior,crossing-1 from phantom to quintessence regime as the universe *** investigate under what situation this type of evolution could be achieved from the perspectives of field theories and modified *** particular,we reconstruct the corresponding actions for f(R),f(T),and f(Q)gravity,*** explicitly show that,certain modified gravity can exhibit the quintom dynamics and fit the recent DESI data efficiently,and for all cases the quadratic deviation from theΛCDM scenario is mildly favored.

关键词： DESI Dark energy Quintom cosmology Modified gravity

石墨烯/GaN异质结构界面热输运性质的分子动力学研究

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物理学报 2024年第13期73卷 327-335页

作者：刘东静周福胡志亮黄家强桂林电子科技大学机电工程学院广西制造系统与先进制造技术重点实验室桂林541004

异质结构界面热输运的性能决定微纳米器件工作的可靠性.本文采用分子动力学方法,研究石墨烯/GaN三明治结构异质界面的热输运特性,分析温度、缺陷以及尺寸对异质结构界面热导的影响.研究发现,随着温度的升高,界面热导增大;当温度为1100 K... 详细信息

异质结构界面热输运的性能决定微纳米器件工作的可靠性.本文采用分子动力学方法,研究石墨烯/GaN三明治结构异质界面的热输运特性,分析温度、缺陷以及尺寸对异质结构界面热导的影响.研究发现,随着温度的升高,界面热导增大;当温度为1100 K时,3层石墨烯异质结构的界面热导增大61%,分析认为这主要是温度升高导致晶格振动增加,进而激发更多的平面外声子.GaN中的少量空位缺陷导致界面热导增大,当缺陷率为20%时,界面热导达到最大值0.0357 GW/(m^(2)·K),分析认为缺陷会增加额外的热输运通道;随后界面热导开始降低,分析认为缺陷率增大导致界面耦合强度降低.随着GaN层数从8层增加到24层,界面热导下降,计算声子模态发现参与界面热输运声子数量减少;而石墨烯从2层到6层时,界面热导先上升后下降,分析认为这是与声子匹配和耦合强度的初期提高和后期声子散射及局部化增加有关.该研究结果为调控微电子器件界面热输运提供理论依据.

关键词：异质结构界面热导空位缺陷尺寸效应

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Genomic variation,environmental adaptation,and feralization in ramie,an ancient fiber crop

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Plant Communications 2024年第8期5卷 189-207页

作者： zeng-Yuan Wu Mark A.Chapman Jie Liu Richard I.Milne Ying zhao Ya-Huang Luo Guang-fu zhu Marc W.Cadotte Ming-Bao Luan Peng-zhen Fan Alex K.Monro zhi-Peng Li Richard T.Corlett De-zhu Li Germplasm Bank of Wild Species&Yunnan Key Laboratory of Crop Wild Relatives Omics Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China School of Biological Sciences University of SouthamptonSouthampton SO171BJUK CAS Key Laboratory for Plant Diversity and Biogeography of East Asia Kunming Institute of BotanyChinese Academy of SciencesKunmingYunnan 650201China Institute of Molecular Plant Sciences School of Biological SciencesUniversity of EdinburghEdinburgh EH93JHUK Department of Biological Sciences University of Toronto-ScarboroughTorontoOntarioCanada Institute of Bast Fiber Crops Chinese Academy of Agricultural SciencesChangshaHunan 410205China Royal Botanic Gardens Kew RichmondSurrey TW93AEUK Center for Integrative Conservation and Yunnan Key Laboratory for the Conservation of Tropical Rainforests and Asian Elephants Xishuangbanna Tropical Botanical GardenChinese Academy of SciencesMenglunYunnan 666303China

Feralization is an important evolutionary process,but the mechanisms behind it remain poorly ***,we use the ancient fiber crop ramie(Boehmeria nivea(L.)Gaudich.)as a model to investigate genomic changes associated with both domestication and *** first produced a chromosome-scale de novo genome assembly of feral ramie and investigated structural variations between feral and domesticated ramie ***,we gathered 915 accessions from 23 countries,comprising cultivars,major landraces,feral populations,and the wild *** on whole-genome resequencing of these accessions,we constructed the most comprehensive ramie genomic variation map to ***,demographic,and admixture signal detection analyses indicated that feral ramie is of exoferal or exo-endo origin,i.e.,descended from hybridization between domesticated ramie and the wild progenitor or ancient *** ramie has higher genetic diversity than wild or domesticated ramie,and genomic regions affected by natural selection during feralization differ from those under selection during *** analyses showed that feral and domesticated ramie have similar ecological niches that differ substantially from the niche of the wild progenitor,and three environmental variables are associated with habitat-specific adaptation in feral *** findings advance our understanding of feralization,providing a scientific basis for the excavation of new crop germplasm resources and offering novel insights into the evolution of feralization in nature.

关键词： ramie fiber offering