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Nearly degenerate ground states of a checkerboard antiferromagnet and their bosonic interpretation

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Science china(Physics,mechanics & Astronomy) 2024年第1期67卷 84-89页

作者： Haiyuan zou Fan Yang Wei Ku Key Laboratory of Polar Materials and Devices(MOE) School of Physics and Electronic ScienceEast China Normal UniversityShanghai 200241China Department of Physics Beijing Institute of TechnologyBeijing 100081China Tsung-Dao Lee institute Shanghai 200240China Key Laboratory of Artificial Structures and Quantum Control(Ministry of Education) Shanghai 200240China Shanghai Branch Hefei National LaboratoryShanghai 201315China

The spin-1/2.model system with antiferromagnetic(AF) couplings on a J1-J2.heckerboard lattice, known as the planar pyrochlore model, is strongly frustrated and associated with a two-to-one dimensional crossover. Using the Projected Entangled Simplex States tensor network ansatz, we identify a large number of nearly degenerate states in the frustrated region(J_(1)2.).Specifically, we find the long-sought crossed-dimer valence bond solid(VBS) state to be the ground state at J_(1)≤J_(2., while various 1D AF correlated states take over the rest. We verify the stability of the VBS state against nematic perturbation. The corresponding bosonic picture provides an intuitive understanding of the low-energy physics. Particularly, it predicts weaker VBS states in the easy-plane limit, which we confirm numerically. Our results clarify the most essential ground state properties of this interesting system and demonstrate the usefulness of bosonic picture in dealing with frustrated magnetism.

关键词： tensor networks frustrated magnetism dimensional crossover degenerate states

提速区段直线钢轨交替不均匀侧磨的成因及其影响

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铁道学报 2002年第3期24卷 49-56页

作者：柴雪松罗林铁道科学研究院铁道建筑研究所北京100081

介绍了国内外文献中很少提及 ,但在我国快速线上部分区段存在的直线段钢轨交替不均匀侧磨及其形态特征。通过仿真分析和试验 ,发现直线钢轨交替侧磨的原因是货车蛇行失稳 ,同时线路方向不平顺对车轮横向振动起到了相位整理作用。因此 ,... 详细信息

介绍了国内外文献中很少提及 ,但在我国快速线上部分区段存在的直线段钢轨交替不均匀侧磨及其形态特征。通过仿真分析和试验 ,发现直线钢轨交替侧磨的原因是货车蛇行失稳 ,同时线路方向不平顺对车轮横向振动起到了相位整理作用。因此 ,解决钢轨的交替不均匀侧磨问题 ,关键在于提高车辆的蛇行临界失稳速度。控制线路上的较大幅值的方向不平顺 ,也有助于抑制钢轨交替性侧磨的形成。研究还发现 ,交替侧磨形成的方向不平顺比轨距不平顺对车辆有着更大的影响 ,尤其是对于快速客车车辆的车体加速度有较大影响 ,从而会影响旅客乘坐的舒适性。

关键词：提速区段直线钢轨交替不均匀侧磨成因稳定性铁路机车车辆

Complex petroleum accumulating process and accumulation series in the buried-hill trend in the rift basin:An example of Xinglongtai structure trend,Liaohe subbasin

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Science china Earth sciences 2008年第S2期51卷 108-116页

作者： GAO XianZhi1,PANG XiongQi1,LI XiaoGuang2.CHEN ZhenYan2.SHAN JunFeng2.LIU Feng1,zou ZhiWen1 & Li WeiLian1 1 Faculty of Resources and Information Technology,china University of Petroleum,{2. 102.49,china 2.Exploration and Development institute of Liaohe Oilfield,Petrochina Liaohe Oil Company,Panjin 12.010,china china Univ Petr Fac Resources & Informat Technol Beijing 102249 Peoples R China Petrochina Liaohe Oil Co Explorat & Dev Inst Liaohe Oilfield Panjin 124010 Peoples R China

The buried-hill trend is a typical style of the petroliferous structure in the faulted basin of eastern china. The Xinglongtai structure trend in the Liaohe subbasin,Bohai Bay Basin is a buried faulted-hill trend resulting from the periodic faulting of the Tai’an-Dawa faults. The structure was cut by various faults,which are interlinked and constitute the conduits for petroleum migration. Petroleum accumulated in the Tertiary sandstones and pre-Tertiary basement of metamorphosed rocks through the migration pathways of the fault system. Petroleum in the structure was derived from different hydrocarbon kitchens to form a hybrid field complex. Petroleum charged the structure from different directions and accumulated in various reservoirs through different pathways in different times. The accumulations in the buried hill trend of Xingongtai are composed of two types of traps in the two stratigraphic systems: traps in the Tertiary sandstones were formed by the fault blocks and by the pinchout of the sandstone,and traps in the pre-Tertiary basement of metamorphosed rocks were formed by fissures in the inner part of the buried hills and by the unconformity near the surface of the buried hills.

关键词： faulted basin petroleum migration and accumulation petroleum occurrence buried hills Achaean basement Liaohe subbasin Bohai Bay basin

PREPARATION OF TiN FILMS BY N_2.ASSISTED Xe^+ ION BEAM ENHANCED DEPOSITION AND THEIR MECHANICAL PROPERTIES

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Acta Metallurgica sinica(English Letters) 1992年第11期5卷 370-374页

作者： WANG Xi YANG Genqing LIU Xianghuai ZHENG Zhihong HUANG Wei ZHOU Zuyao zou Shichang Ion Beam Laboratory,Shanghai institute of Metallurgy,{2.,shanghai,china Shanghai Inst of Metallurgy Acad Sinica Shanghai China

A new method for preparation of hard TiN films has been developed by using electron beam evaporation-deposition of Ti and bombardment with 40 keV Xe^+ ion beam in a N_2.gas *** synthesized TiN films were superior to PVD and CVD ones in respects of improved adhesion to substrate and low preparing *** exhibited good wear resistance and high hardness up to 2.00 kg/mm^*** industrial applications have been reported.

关键词： TiN film ion beam enhanced deposition mechanical properties

Regional container transportation system for Northeast Asia economic cooperation in the 2.^(st) century

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Journal of Geographical sciences 2000年第4期10卷 59-66页

作者： JIN Feng-jun (institute of Geographic sciences and Natural Resources Research, Chinese Academy of sciences, beijing 100101, china) 中科院地理科学与资源所北京

In this paper, the roles of infrastructure development and transportation coordination for Northeast Asian economic cooperation are discussed. It would be necessary to establish an efficient transportation network as soon as possible. 'Hub-and-Spoke'transportation system and china-Korean peninsula railway container transportation system might be more significant for regional economic cooperation.

关键词： infrastructure economic cooperation transportation organization Hub-and-Spoke system high-speed transport

Surface Profiles and Residual Stresses on Laser Shocked Zone of Ti6Al4V Titanium Alloy

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稀有金属材料与工程 2011年第S4期40卷 190-193页

作者： Cao Ziwen,Gong Shuili,zou Shikun,Che Zhigang National Key Laboratory of High Energy Density Beam Processing Technology,beijing Aeronautical Manufacturing Technology Research {2.,beijing 10002.,china beijing Aeronaut Mfg Technol Res Inst Natl Key Lab High Energy Dens Beam Proc Technol Beijing 100024 Peoples R China

The latest applications of laser shock processing were summarized in this paper,and laser peening with water confined layer has been applied to Ti6Al4V titanium alloy using Nd:glass pulse *** profile of plastic deformation and residual stresses on metal surface were studied with different laser power *** investigation results show that peak depth of plastic deformation is in linear proportion to laser power density (5.75GW/cm2.to 9.5 GW/cm2.,and maximal surface compressive residual stress is up to 375MPa at 8.2.GW/*** was ensured that the compressive residual stress field related to laser power density and shocked *** spot overlapping ratio of 33%,the circle spot can get a relative smooth *** strip with thickness 2.5mm was shocked as the preliminary verification test of residual stresses,and it is shown that excessive peening times is unavailable to thin-wall parts just as edge of fan blades.

关键词： laser shock processing Ti6Al4V surface profiles residual stresses

NUCLEATION AND GROWTH OF FERROUS MARTENSITES ALONG BOUNDARIES

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Acta Metallurgica sinica(English Letters) 1991年第6期4卷 426-430页

作者： GONG Hai ZHANG Weiyi Dalian railway institute,Dalian,{2.ZHANG Xiumu institute of Metal Research,academia sinica,Shenyang,{2.

Martensites distributed along the austenite grain boundaries and twin boundaries have been examined in Fe-C,Fe-Ni-C and Fe-Cr-Mn-Mo-C *** martensites may nucleate preferentially and grow easily along these *** the mix... 详细信息

关键词： martensite nucleation martensite growth martensite morphology grain boundary twin boundary plate martensite

Study on Internet of Things application for Highspeed Train Maintenance,Repair and Operation（MRO）

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Study on Internet of Things application for Highspeed Train ...

Alterations in DNA methylation and genome structure in two rice mutant lines induced by high pressure

2.12.National Conference on Information Technology and Computer Science

作者： Weijiao ZHANG institute of Computing Technology china Academy of {2. sciences beijing,china

the design of EMU IoT-system,which is oriented to the MRO of high-speed trains,was studied with implementations of sensing technologies like RFID,sensors,etc;with regarding to the future requirements of safety,orderly,efficient and high-quality in EMU maintenance service of *** operation:massive seamless embedded RFID tags and sensors,on the basis of trainground transmission network,perceive running and defects status of high-speed train in real-time;realizing holographic train visualization and transit *** maintenance and repair:multisource and multilevel raw data,from the collection of various production aspects such as trains flow,parts flow,labor jobs flow and equipments,monitor productive process and logistics of train maintenance in total life *** general framework and detailed technical solution were presented in this paper;for the efficient processing of raw data,a semantic analysis measure driven by complex event mechanism was introduced;finally,a quantitative evaluation of productivity upgrading owing to IoT was *** RFID applications involved are running or experienced pilot tests in factory environment.

关键词： intelligent transportation internet of things (IoT) high-speed trian semantic analysis complex event processing

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Science china(Life sciences) 2006年第2期49卷 97-104页

作者： SHEN Sile1,3, WANG Zhenwei3, SHAN Xiaohui2. WANG Hua3, LI Ling3, LIN Xuyun2. LONG Likun2. WENG Kenan4, LIU Bao2.& zou Guangtian1 1. National Laboratory of Superhard Materials, Jilin University, Changchun 130012. china 2. {2. of Genetics and Cytology, Northeast Normal University, Changchun 13002., china 3. College of Life Science, Jilin University, Changchun 130012. china 4. Guangzhou {2. of Geochemistry, Chinese Academy of sciences, Guangzhou 510640, china 1. National Laboratory of Superhard Materials Jilin University Changchun 130012 China 3. College of Life Science Jilin University Changchun 130012 China 2. institute of Genetics and Cytology Northeast Normal University Changchun 130024 China 4. Guangzhou institute of Geochemistry Chinese Academy of Sciences Guangzhou 510640 China

By using high-pressure treatment, two mutant lines were obtained from agenetically stable japonica rice cultivar Bijing38. Genomic DNA of the mutant lines, together withthe original line (Bijing38), was either undigested or digested by Hpa ⅡIMspⅠ, and then subjectedto molecular analysis using two markers, ISSR and RAPD. Results indicated that changes in the PCRamplification profiles of both markers are apparent in the two mutant lines compared with theoriginal rice cultivar, suggesting that there had been both sequence changes and DNA methylationmodifications in the mutant lines. Southern blot analysis using diverse sequences, including twocellular genes (S2.and S3), a set of retrotransposons (Osr7, Osr36, Tos19 and more), and a MITEtransposon family (mPing and Pong), confirmed the results, and indicated that changes in DNAmethylation pattern, genomic structure, and possible activation of some transposons indeed occurredin the mutant lines. Moreover, these changes are stably maintained through selfed generations and indifferent organs. Thus, our results indicate that it is possible to obtain stable mutants in riceby high pressure treatments, and the molecular basis of the mutants may include both genetic andepigenetic changes. Therefore, high hydrostatic pressure seems a promising approach for plantmutagenesis.

关键词： DNA methylation, genomic changes, high pressure, mutagenesis, rice.