Recrystallization Texture and Microstructure of Metal Substrate for Y123 Coated Superconductor

Thesecondgenerationofhigh temperaturesuper conductingtapesusingYBCO 12 3superconductorhavebeenanattractivesubjectinrecentyears .IncomparisonwithBibasedsuperconductors ,YBCOshowsbetterirreversibility ,lowAClosscapabilityandhighcriticalcurrentdensityJC inhighmagneticfields[1] .However ,owingtoitspropertyofphysicalmetallurgy ,YBCOtapescannotbeproducedbyOPIT(OxidePowderinTube)technique ,whichhasbeenusedinBibasedsuperconductorsuccessfully[2 ] .Fur thermore ,poorintergrainbondinginpolycrys…     

雷达距离测量的数字化进程

简要阐述了雷达对目标距离测量的基本原理和发展过程，着重叙述了在现代新型雷达体制下对目标距离跟踪的新方法，并对其进行了相关的性能分析。     

5BF-3型水果分级机构动力学仿真分析

三维动态仿真既可以反映其运动过程,又可实现速度可控制的动画演示,清晰再现其运动过程,利于分析机械系统性能.根据5BF-3型辊-带水果分级机建立ADAMS多体动力学仿真模型,观察柑橘质心运动轨迹,验证动力学分析得出的柑橘正确分级条件,结果表明,分析可靠,正确.     

川中-川南过渡带须家河组天然气成藏条件与主控因素分析

通过对须家河组构造演化、成藏过程、圈闭与烃源岩的时空配置关系等成藏地质条件的综合分析认为,控制川中-川南过渡带须家河组天然气成藏的主要因素包括：充足的烃源岩是油气成藏的物质基础;中三叠统侵蚀面是油气横向运移的主要通道;印支末期古构造带的发育是油气富集的关键,其中后2个因素通过沟通油气源、有利沉积相带和形成圈闭等作用控制着油气的成藏。     

Improvement of epitaxy and crystallinity in YBa2Cu3Oy thin films grown on silicon with double buffer of ECO/YSZ

A novel double buffer of Eu2CuO4 （ECO）/YSZ （yttrium-stabilized zirconia） was developed for growing YBa2Cu3Oy （YBCO） thin films on Si substrates. In these films, the severe reaction between Si and YBCO is blocked by the first YSZ layer, whereas, the degradation of crystallinity and superconductivity in the grown YBCO is greatly improved by the second ECO layer. Such an ECO material possesses a very stable 214-T＇ structure and excellent compatibilities with YBCO and YSZ. The result shows that the epitaxy and crystallinity of YBCO deposited on Si could be considerably enhanced by using the ECO/YSZ double buffer. The grown films are characterized by high-resolution X-ray diffraction, grazing incidence X-ray reflection, and transmission electron microscopy （TEM）, respectively. It is found that well defined interfaces are formed at YBCO/ECO/YSZ boundaries. No immediate layer could be seen. The defect density in all grown layers is kept at a lower level. The YBCO film surface turns out to be very smooth. These films have full superconducting transitions above 88 K and high current carrying capacity at 77 K. The successful growth of highly epitaxial YBCO thin films on silicon with ECO/YSZ buffer, demonstrate the advantages of such a double buffer structure.     

含复铰平面运动链拓扑对称性识别的邻接矩阵方法

提出了识别含复铰平面运动链拓扑对称性的邻接矩阵方法。根据能够反映复铰和多副杆特点的构件邻接矩阵和铰链点关联矩阵,按照构件或铰链点的划分,利用圆排列转动和圆排列对应匹配的方法进行构件或铰链点拓扑对称性的识别,并提出了基本算法。研究表明:该方法能应用于无复铰平面运动链,并且具有简便、直观、可靠和便于用计算机进行处理等特点。     

用定心套车削轴套夹具

我厂加工如图1所示的工件,此工件内孔是一层复合材料,已加工至尺寸,现要车削外圆。由于内孔是复合材料不能直接用卡爪夹紧,夹外圆车削很难保证内外圆同心。为此,我们自制了简易的工装,如图2所示。     

运动副间隙对平面连杆机构运动误差影响的模拟实验研究

利用蒙特卡洛方法在计算机上进行模拟实验,由轴、孔可能的接触情况假设接触角的均匀分布区间,由随机抽样确定间 隙和接触角的模拟值,直接应用机构运动分析的杆组法及相应的程序求解。     

平面运动链型综合组合法开链规划的一种改进方法

提出了平面闭式运动链型综合组合法中开链规划的改进方法。为获得给定自由度和构件数的全部独立的运动链结构类型,按照构件数递增的顺序,将开链与相应的闭链进行组合。在开链规划中,如果必要仅需对单杆开链增设铰链,然后依次选定二杆开链、三杆开链等,直到自由度加一的两副杆串联开链,开链规划即可停止。指出了上述方法在型综合应用中的正确性,并从理论上进行了探讨。