PST双相TiAl类单晶中的微孪晶变形

利用透射电子显微镜研究了ＰＳＴ双相ＴｉＡｌ类单晶中的微孪晶变形行为，研究结果表明，孪晶面为（１１１），是由（α／６）Ｓｈｏｃｋｌｅｙ不全位错在（１１１）面上运动产生的，当该位错遇到到互在孪晶关系的两片ＴｉＡｌ界面时，将在另一片ＴｉＡｌ相中诱发出新的微孪晶，其孪晶系统不变，这说明互成孪晶关系的ＴｉＡｌ相界面对微孪晶变形阻碍作用不大，本文讨论了微孪晶变形对材料变形的影响。     

THE BEHAVIOUR OF1/2[112] SUPERLATTICE DISLOCATIONSIN POLYSY NTHETICALLY TWINNED CRYSTALS OF TiAl

１　ＩＮＴＲＯＤＵＣＴＩＯＮＩｎｔｅｒｍｅｔａｌｌｉｃＴｉＡｌａｌｌｏｙｓｈａｖｅｒｅｃｅｉｖｅｄａｇｒｅａｔｄｅａｌｏｆａｔｔｅｎｔｉｏｎｄｕｒｉｎｇｔｈｅｐａｓｔｆｅｗｙｅａｒｓａｎｄａｒｅｃｏｎｓｉｄｅｒｅｄａｓｎｅｗｌｉｇｈｔｗｅｉｇｈｔｈｉｇｈｔｅｍｐｅｒａｔｕｒｅｍａｔｅｒｉａｌｓｂｅｃａｕｓｅｏｆｔｈｅｉｒａｔｔｒａｃｔｉｖｅｐｒｏｐｅｒｔｉｅｓｓｕｃｈａｓｌｏｗｄｅｎｓｉｔｙａｎｄｇｏｏｄｈｉｇｈｔｅｍｐｅｒａｔｕｒｅｐｒｏｐｅｒｔｉｅｓ．Ｂｏｔｈｓｉｎｇｌｅｐｈａｓｅａｎｄ…     

生长激素（PST）脂质体的制备初探

采用冰冻熔融法制备脂质体,包封率进行测定可达29％。同时对影响包封率的因素进行了分析,得出卵磷脂：胆固醇为5：2,超声时间为3min,中性环境,冰冻24h或冷藏3d,4℃左右贮存,其稳定性良好,包封率几乎无变化。     

片层取向对Ti—49at%AlPST晶体断裂机制的影响

用ＳＥＭ原位拉伸技术研究了Ｔｉ－４９ａｔ％ＡｌＰＳＴ晶体的断裂过程,研究表明：裂纹萌发和扩展路径强烈依赖于ＰＳＴ晶体的片层取向;不同取向ＰＳＴ晶体具有不同的断裂机制及断口形貌。     

公路下伏采空区注浆质量检测技术研究进展

针对高速公路下伏采空区注浆工程质量的各种检测方法进行了介绍,包括：钻孔法、地表变形监测法及物探法等,分别阐述了每种检测方法的适用性及优缺点,以期为工程实践提供指导和帮助。     

Impact of Optimal Unified Power Flow Controller in Electrical Transmission Systems in Reducing Transmission Cost

This paper presents an approach to optimal placement of optimal unified power flow controller (OUPFC) in electrical transmission systems utilizing genetic algorithm (GA), while reducing transmission systems cost using MATLAB and MATPOWER. The proposed approach is based on optimal power flow (OPF) considering optimization of power systems operation conditions. In order to determine the appropriate place for installation of OUPFC, while considering power injection model of this controller, OPF is utilized to obtain multi-objective function of the optimization problem. In this regard, the objective function comprises generation cost, transmission cost, and OUPFC installation cost. The proposed approach is applied to IEEE 30-bus test system, where the obtained results demonstrate remarkable reduction in overall cost of power system.     

A Model of Phase Transition Kinetics in Lead Scandium Tantalate Thin Films

The phase transformations from amorphous to pyrochlore to perovskite in lead scandium tantalate (PST) thin films during rapid thermal annealing process (RTA) have been studied by X-ray diffraction (XRD) techniques. The growth and decay of the pyrochlore phase, the growth of the perosvkite PST were analysed using the Avrami model. Integral equations have been derived and numerical calculation been used to simulate the volume fractions for pyrochlore and perovskite as functions of annealing time. Transformation parameters k and n were obtained by comparing the simulated to the experimental intensities using a least-squares curve fitting technique. Activation energies for perovskite formation were calculated. The results indicate that the phase transitions are diffusion-limited. TEM, SEM, and EDS were employed to study the lead loss and other factors affecting phase transitions.     

CHARACTERISTIC OF (100)-TEXTURED (PbxSr1 −x)TiO3 THIN FILMS USED FOR DRAM AND TUNABLE DEVICE APPLICATION

ABSTRACT

The (Pb_xSr_1-x)TiO₃ (PST) thin films were deposited on LaNiO₃ (LNO(1 0 0))/ Pt/Ti/SiO₂/Si substrates electrode by RF-magnetron sputtering using three different Pb target composition ranging from 32.5%～37.5% and different process condition. Structural and dielectric properties of the PST thin films for tunable microwave and DRAM application were investigated. The PST thin films deposited at 400°C show higher dielectric constant than those post-annealed at 600°C because of better crystallization. The former also have lower leakage current around 10^?8 A/cm² up to applied field of 350 kv/cm, which is suitable for DRAM application. On the other hand, the post-annealed PST thin films have satisfactory tunability around 58% and figure of merit around 30, which are more suitable for microwave device application.     

星载大气痕量气体差分吸收光谱仪杂散光抑制

考虑杂散光对星载大气痕量气体差分吸收光谱仪测量精度的影响,设计了遮光罩和其他消杂光结构来抑制杂散光,并对杂散光进行了分析。利用TracePro软件分析了系统紫外通道1(240～315nm)的杂散光水平,确定了杂散光传输的一次、二次散射路径。根据杂散光传输路径,计算了杂散光评价指标点源透射比(PST)曲线,结果显示杂散光抑制措施效果明显,PST小于3×10-5,中心视场杂散光照度水平为5.472×10-4,最终杂散光水平达到了设计指标要求。采用截止滤光片法测量了系统的杂散光水平,结果表明:中心视场杂散光比值为8.167×10-4,和仿真结果接近,验证了仿真过程的准确性,说明设计的消杂光机构能够满足抑制系统杂散光的要求。     

PST控制器车载实时监测系统开发中关键问题研究

针对汽车电动脚踏板(PST)控制器设计一种基于LabVIEW的车载实时监测系统,解决了高速数据采集机制的选择、高速存储以及关键性能参数的提取等问题,通过长时间的车载监测结果验证了系统的稳定性和高效性。