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Superconductivity 2022年第1期1卷 27-33页

作者： j.Li y.Shi G.M.Zhang L.W.jing j.X.Zheng C.L.Liu W.yuan y.S.Wang M.Song y.j.xia X.H.Zong y.W.Han D.N.Zheng X.j.Zhou T.Matsushita G.Nishijima The Institute of Physics Chinese Academy of SciencesBeijing 100190China The Institute of Electrical Engineering Chinese Academy of SciencesBeijing 100190China The Institute of Plasma Physics Chinese Academy of SciencesHefei 230031China Eastern Superconductor Science&Technology(Suzhou)Co LtdSuzhou 215299China Guangdong Power Grid Corporation Guangzhou 510630China Shanghai International Superconductor Technology Co LtdShanghai 200444China Department of Computer Science and Electronics Kyushu Institute of Technology Iizuk1Japan National Institute for Materials Scienc5 Tsukuba 305-0003Japan

Currently,IEC/TC90 is working on standardizing the method for measuring critical current(Ic)in superconducting *** the end of 2020,an international round robin test(RRT)was organized,in which five Chinese institutions participated,and four accomplished the *** electric-field versus current(E-I)curves obtained by each institution are highly *** obtained by different institutions are nearly identical after appropriate curve averaging,indicating high reproducibility,except the last participant's inner core *** discrepancy was later determined to be the result of sample cable *** excluding highly deviated data,it is determined that the maximum relative standard uncertainty in I_(c) is 0.7%,and the maximum relative standard uncertainty in n-value is 12.8%.The I_(c)values are comparable to japan's domestic RRT results,but the n-values are significantly *** test results support the DC four-terminal method as a recommended test method,with a target relative uncertainty of less than 2%for the Ic value.

关键词： Superconducting cable Round robin test Standardization

Statistical moment-based structural damage detection method in time domain

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Earthquake Engineering and Engineering Vibration 2013年第1期12卷 13-23页

作者： j.Zhang y.L.Xu j.Li y.xia j.C.Li Department of Civil and Environmental Engineering The Hong Kong Polytechnic University Department of Building Engineering Tongji University Faculty of Engineering University of Technology Sydney

A novel structural damage detection method with a new damage index,i.e.,the statistical moment-based damage detection（SMBDD） method in the frequency domain,has been recently *** aim of this study is to extend the SMBDD method in the frequency domain to the time domain for building structures subjected to non-Gaussian and non-stationary *** applicability and effectiveness of the SMBDD method in the time domainis verified both numerically and *** buildings with various damage scenarios are first numerically investigated in the time domain taking into account the effect of measurement *** applicability of the proposed method in the time domain to building structures subjected to non-Gaussian and non-stationary excitations is then experimentally investigated through a series of shaking table tests,in which two three-story shear building models with four damage scenarios *** identified damage locations and severities are then compared with the preset *** comparative results are found to be satisfactory,and the SMBDD method is shown to be feasible and effective for building structures subjected to non-Gaussian and non-stationary excitations.

关键词： damage detection statistical moment time domain non-Gaussian non-stationary experimental investigation

Trans-scale mechanics: looking for the missing links between continuum and micro/nanoscopic reality

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Acta Mechanica Sinica 2008年第2期24卷 111-126页

作者： y.L.Bai H.y.Wang M.F.xia F.j.Ke State Key Laboratory of Non-linear Mechanics (LNM) Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China State Key Laboratory of Non-linear Mechanics (LNM) Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China Department of Physics Peking University Beijing 100871 China State Key Laboratory of Non-linear Mechanics (LNM) Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China Department of Applied Physics Beihang University Beijing 100083 China

Problems involving coupled multiple space and time scales offer a real challenge for conventional frame-works of either particle or continuum mechanics. In this paper, four cases studies （shear band formation in bulk metallic glasses, spallation resulting from stress wave, interaction between a probe tip and sample, the simulation of nanoindentation with molecular statistical thermodynamics） are provided to illustrate the three levels of trans-scale problems （problems due to various physical mechanisms at macro-level, problems due to micro-structural evolution at macro/micro-level, problems due to the coupling of atoms/ molecules and a finite size body at micro/nano-level） and their formulations. Accordingly, non-equilibrium statistical mechanics, coupled trans-scale equations and simultaneous solutions, and trans-scale algorithms based on atomic/molecular interaction are suggested as the three possible modes of trans-scale mechanics.

关键词： Multi-scale Missing-links Continuum mechanics Particle mechanics Trans-scale mechanics

论新时代全面深化改革的历史逻辑、理论逻辑和现实逻辑

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新疆师范大学学报（哲学社会科学版） 2025年第1期46卷 50-59页

作者：张夏恒西北政法大学商学院(管理学院) 陕西西安710122

新时代全面深化改革具有深厚的历史逻辑、丰富的理论逻辑和鲜明的现实逻辑。从历史逻辑看,全面深化改革始于党的十一届三中全会,提出于党的十八届三中全会,成熟于党的二十届三中全会。从理论逻辑看,全面深化改革概念历经从改革与开放到... 详细信息

新时代全面深化改革具有深厚的历史逻辑、丰富的理论逻辑和鲜明的现实逻辑。从历史逻辑看,全面深化改革始于党的十一届三中全会,提出于党的十八届三中全会,成熟于党的二十届三中全会。从理论逻辑看,全面深化改革概念历经从改革与开放到改革开放,从全面改革到深化改革,再从全面改革、深化改革到全面深化改革的演化,全面深化改革以马克思主义、党的领导、中国特色社会主义、习近平新时代中国特色社会主义思想等为理论支撑。从现实逻辑看,新时代全面深化改革不仅体现了中国特色社会主义进入新时代改革的重要性与必要性,而且全面深化改革是应对中国改革面临的诸多挑战和机遇的时代选择,要将以人民为中心、坚持党的领导、推进国家治理体系和治理能力现代化、坚持社会主义制度、构建高水平社会主义市场经济体制、因地制宜发展新质生产力等作为新时代全面深化改革的现实抓手与工作重心。

关键词：新时代全面深化改革改革开放党的二十届三中全会党的十八届三中全会党的十一届三中全会

THE CREEP AND FRACTURE BEHAVIOR OF TWO NICKEL-BASED SUPERALLOyS

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Acta Metallurgica Sinica(English Letters) 1998年第6期11卷 425-428页

作者： S.H.Ai y.B.xia j.F.Tian Inst of Metal Research Chinese Acad of Sciences Shenyang China

The creep and fracture behavior of the cast K417 and forged GH4049 nickel-based superalloys were investigated in the temperature range of 700-900℃ C. Within the ranges of stress and temperature studied, the steady state creep rates exhibited a power law relationship with the applied stress and temperature. The time to rupture is inversely proportional to the steady state creep rate. Under all testing conditions, the creep fracture process was mainly controled by crack initiation and growth of the intergranular oxidation. Casting porosities, pores and carbides were also prefecentral locations of creep crack initiation in the cast K417 alloy. In addition, the intergranular fracture feature in the forged GH4049 alloy was apparently associated with the formation and coalescence of the cavitations on the grain boundaries.

关键词： superalloy creep rate fracture

On the mechanism of Si-promoted destabilization of TiC_(x)particles in Al alloys

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journal of Materials Science & Technology 2023年第34期165卷 17-26页

作者： H.Dong y.C.Guo y.Z.Chen F.xia Q.Q.Guo Q.Chen G.L.Li j.y.Zhao y.Zhong j.P.Li School of Materials and Chemical Engineering Xi’an Technological UniversityXi’an 710021China State Key Lab.of Solidification Processing Northwestern Polytechnical UniversityXi’an 710072China School of Science Xi’an University of Science and TechnologyXi’an 710054China

TiC_(x)is an excellent composite strengthening particle and grain refiner for Al ***,the stability of TiC_(x)is poor when solute Si exists in Al alloy melts,which significantly depresses its strengthening and grain refining *** this work,the destabilization mechanisms of the TiC_(x)particles in Al-Si alloy melt with a composition of Al-7Si-7.5TiC were explored via experiments,first-principles calculations and thermodynamic *** experimental results show that Si atoms diffuse into TiC_(x)and Ti atoms are released into the Al melt to form a Ti-rich transition zone during the insulation of TiC_(x)in Al-Si melt,and the TiAlySiz and Al_(4)C_(3)phases are solidified in the Ti-rich zone and at Ti-rich zone/TiC_(x)interface,*** first principles calculations show that the low formation energy of C vacancies facilitates the rapid diffusion of Si atoms in TiC_(x),while the doping of Si atoms reduces the energy barrier of diffusion of Ti atoms in TiC_(x)and promotes the formation of Ti-rich *** thermodynamic calculations show that the wide crystallization temperature range of the destabilized product TiAlySiz phase is the key to continuous decomposition of TiC_(x)*** addition,the driving force of the main destabilization reaction of TiC_(x)in the Al-Si alloys is about 44 times higher than that in the Al alloys without Si *** indicates that the presence of solute Si remarkably promotes the subsequent decomposition process of TiC_(x)in the Al-Si alloy melts.

关键词： Al-Si alloy TiC_(x)particles Destabilization First principles calculations Thermodynamics

XPS INVESTIGATION OF NITROGEN IONS IMPLANTED INTO ALUMINUM ALLOy By PLASMA BASED ION IMPLANTATION

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Acta Metallurgica Sinica(English Letters) 1999年第5期12卷 771-776页

作者： Zhan, Z.j. Ma, X.X. xia, L.F. Sun, y. Harbin Inst of Technology Harbin China

Aluminum alloy 2024 has been implanted with nitrogen ions at various doses by plasma based ion implantation. The introduction of energetic ions causes structural change within the near surface region of the solid. The samples have been characterized by X-ray Photoelectron Spectroscopy at various depths. The chemical states of Al and N were identified by deconvolution of the recorded XPS spectra. After plasma based ion implanted nitrogen into aluminum, not only the AlN precipitates but also super saturated solution of nitrogen forms. The presence of aluminum in different chemical states is corresponding to Al, AlN and Al2O3. The majority of nitrogen is in the form of the supersaturated solution. With the increase of nitrogen dose, the amount of AlN precipitates increases.

关键词： Aluminum compounds Ion implantation Nitrides Nitrogen Plasma devices Wear of materials

Grain refinement in low SFE and particle-containing nickel aluminium bronze during severe plastic deformation at elevated temperatures

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journal of Materials Science & Technology 2021年第23期82卷 57-68页

作者： C.j.Barr K.xia Department of Mechanical Engineering University of MelbourneVictoria3010Australia DMTC Ltd. 24 Wakefield St.HawthornVIC3122Australia

The influence of particle size and morphology on grain refinement in low stacking fault energy(SFE)alloys was studied by comparing the grain structures in single-and multi-phase Al-bronze(AB)alloys following equal channel angular pressing(ECAP)between 350 and 500℃.In particular,nickel aluminium bronze(NAB)was chosen as it contained both coarse and fine rounded particles,as well as a lamellar phase which evolved during *** refinement in the single-phase alloy was achieved through dynamic recrystallisation initiated at deformed twin *** contrast,different mechanisms were observed in the particle-containing *** around the coarseκⅡparticles(~5μm)was promoted through particle stimulated nucleation(PSN),whereas recrystallisation in the region of the fineκⅣ(~0.4μm)was delayed due to the activation of secondary *** refinement in areas of the lamellarκⅢshowed significant variation,depending on the lamellar orientation relative to the shear plane of *** the lamellae deformed,numerous high angle grain boundaries were generated between fragments and served as nucleation sites for recrystallisation,while PSN occurred around spheroidised *** spreading of theκⅢparticles by ECAP then enhanced the total area of recrystallised grains.

关键词： Equal channel angular pressing Copper alloys Grain refinement Stacking fault energy Severe plastic deformation

Chemical synthesis of a structural gene coding for trichosanthin

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Chinese journal of Chemistry 1995年第4期13卷 349-357页

作者： CHEN, HB xia, y jING, jP jIANG, K BAO, jS CHINESE ACAD SCI SHANGHAI INST ORGAN CHEMCOMP CHEM LABSTATE KEY LAB BIOORGAN & NAT PROD CHEMSHANGHAI 200032PEOPLES R CHINA

A structural gene (750 bp), which codes for a type I ribosome inactivating protein, trichosanthin, has been designed according to the codon usage of highly expressed gene in E. coli and chemically synthesized. In the synthesized gene, twenty-seven unique restriction sites were evenly dispersed with an average distance between two adjacent sites less than 50 bp to facilitate a systematic investigation on structure-functional relationship of this protein by site-directed mutagenesis. To synthesize it, the whole gene was divided into three large fragments (EP, PN and NH) which were assembled from several chemical synthetic oligonucleotides by enzymatic method. The assembly of both the fragment EP from six oligonucleotides (A-F) and the fragment PN from four oligomers (G-j) was catalyzed by T-4 DNA ligase in using the single stranded DNA method [Chen, H.-B. et al., Nucl. Acids Res., 18, 871(1990)]. And fragment NH was formed from three duplexes K, L and M by the classical double stranded DNA method. Finally, each fragment was cloned into vector pUC18 in succession to form the plasmid, pC0TCS, to complete the whole gene synthesis, The sequencing data for the synthetic gene coincides with the designed one.

关键词： RIBOSOME INACTIVATING PROTEIN TRICHOSANTHIN GENE DESIGN GENE SyNTHESIS SyNTHETIC GENE

Application Prospect of Fission-Powered Spacecraft in Solar System Exploration Missions

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Space(Science & Technology) 2021年第1期2021卷 309-323页

作者： y.xia j.Li R.Zhai j.Wang B.Lin Q.Zhou Beijing Institute of Spacecraft Environment Engineering BeijingChina Science and Technology on Reliability and Environmental Engineering Laboratory BeijingChina Institute of Nuclear and New Energy Technology of Tsinghua University The Key Laboratory of Advanced Reactor Engineering and SafetyMinistry of EducationBeijingChina

Fission power is a promising technology,and it has been proposed for several future space *** is being considered for highpower missions whose goal is to explore the solar system and even *** fission power has made great progress when NASA’s 1 kWe Kilowatt Reactor Using Stirling Technology(KRUSTy)prototype completed a full power scale nuclear test in *** success stimulated a new round of research competition among the major space *** article reviews the development of the Kilopower reactor and the KRUSTy system *** summarizes the current missions that fission reactors are being considered as a power and/or propulsion *** projects include visiting jupiter and Saturn systems,Chiron,and Kuiper belt object;Neptune exploration missions;and lunar and Mars surface base *** studies suggest that the Fission Electric Propulsion(FEP)/Fission Power System(FPS)is better than the Radioisotope Electric Propulsion(REP)/Radioisotope Power System(RPS)in the aspect of cost for missions with a power level that reaches~1 kWe,and when the power levels reaches~8 kWe,it has the advantage of lower *** a mission that travels further than~Saturn,REP with plutonium may not be cost acceptable,leaving FEP the only *** missions prefer the use of FPS because it satisfies the power level of 10’s kWe,and FPS vastly widens the choice of possible landing *** to the current situation,we are expecting a flagship-level fission-powered space exploration mission in the next 1-2 decades.

关键词： satis Saturn isotope