Observation of Diffusion Process of a Water Droplet Immersed in Protein Solution in Microgravity

Pure liquid-liquid diffusion driven by concentration gradients is hard to study in a normal gravity environment since convection and sedimentation also contribute to the mass transfer process. We employ a Math Zehnder interferometer to monitor the mass transfer process of a water droplet in EAFP protein solution under micro- gravity condition provided by the Satellite Shi Jian No 8, A series of the evolution charts of mass distribution during the diffusion process of the liquid droplet are presented and the relevant diffusion coefficient is determined.     

Numerical Simulation of Shear-Horizontal-Wave-Induced Electromagnetic Field in Borehole Surrounded by Porous Formation

Seismoelectric fieM excited by purely torsional loading applied directly to the borehole wall is considered. A brief formulation and some computed waveforms show the advantage of using shear-horizontal （SH） transverseelectric （TE） seismoelectric waves logging to measure shear velocity in a fluid-saturated porous formation. By assuming that the acoustic field is not influenced by its induced electromagnetic field due to seismoeleetric effect, the coupling governing equations for electromagnetic field are reduced to Maxwell equations with a propagation current source. It is shown that this simplification is valid and the borehole seismoelectric conversion efficient is mainly dependent on the electrokinetic coupling coefficient. The receivers to detect the conversion electromagnetic field and to obtain shear velocity can be set in the borehole fluid in the SH-TE seismoelectric wave log.     

Phase Transition and High Piezoactivity of Sb Doped （Na0.53K0.435Li0.035）Nb0.94Ta0.06 O3 Lead-Free Ceramics

Lead-free piezoelectric ceramics with the composition of （Na0.53K0.435Li0.035）Nb0.94Ta0.06 O3 （NKLNST） axe synthesized by a conventional solid-state sintering process. An MPB-like region between orthorhombic and pseudocubic phases is found in this system. The density, piezoelectric and dielectric properties axe enhanced greatly in this region. A composition （Na0.53K0.435Li0.035）（Nb0.94Ta0.06）O3 is found to have excellent electrical properties： d33 = 320pC/N, kp= 49% and kt =43%, as well as relatively low loss, tan δ=4.2%, and high relative density higher than 96%, which indicate that this ceramics is a promising lead-free piezoceramics replacing for lead zirconate titanate.     

晶粒间界相对纳米Nd_2Fe_(14)B各向异性和矫顽力的影响

本文采用立方晶粒结构模型研究了晶粒间界相对纳米硬磁材料各向异性和矫顽力的影响.结果表明:晶粒间界相减弱了交换耦合作用.当晶粒尺寸D为定值时,随着晶粒间界相厚度d的增加,晶粒平均各向异性单调增加,而材料的有效各向异性Keff、矫顽力单调减小.我们计算的矫顽力随晶粒尺寸的变化与相关理论和实验结果基本一致.     

高效率激光二极管泵浦100 Hz 3.5 J Nd∶YAG MOPA激光器

研制了结构简单、高效率激光二极管泵浦Nd∶YAGM0PA激光器.振荡级输出单脉冲能量1.13 J,重复频率为100HZ.MOPA系统输出最大单脉冲能量2.35 J,光-光转换效率为39%.实验结果和理论计算符合较好.     

基于shifrin变换反演粒度分布的理论分析

理论上验证了shifrin变换粒度反演算法。采用Fraunhofer衍射理论计算前向散射光强,并利用shifrin变换进行了粒径反演。模拟结果发现,shifrin变换算法能够反演出被测单一或多分散颗粒群的粒径峰值位置,且随着接收CCD像元总数的增加,反演的准确度也会增大,但是在被反演的峰值周围会存在一定数量的小峰。随着接收衍射角的增大,也能相应地增大反演的粒径范围。中心涂黑一定数目的CCD像元并不会对反演结果造成很大的影响。     

单分子操纵与单分子生物物理

文章介绍了近年来发展起来的一些单分子操纵实验技术如光镊、磁镊、微针、斯托克斯拖曳技术，以及应用这些技术拉伸、旋转、解链DNA分子，从而研究其力学性质所取得的研究进展．各种蛋白质如T7 DNA聚合酶、拓扑异构酶，SWI／SNF染色质重建复合体、RNA聚合酶与DNA的作用在生化过程中十分重要，因此，文章也介绍了这些蛋白质与DNA在单分子的水平上相互作用所取得的研究进展．     

交换弹性磁性材料的研究进展

对近年来交换弹性磁性材料（包括高性能永磁和磁存储介质）等方面的最新研究进展作了一些简单的综述，总结了存在的一些问题并指出了用以解决这些问题的可能途径，为进一步的深入研究提供参考。     

筒仓效应观测仪的设计及其应用

设计并制作了观测静态颗粒物质筒仓效应的实验系统,应用该装置研究了筒仓效应的尺寸依赖性.实验结果表明:圆柱形容器中的颗粒物质对于容器底部的饱和压力依赖于容器直径的3次方,而改变填入颗粒的直径时则饱和压力并无明显改变.     

高温超导体环流演示仪

利用永磁铁对超导样品进行激励,产生的超导环流不衰减,由此原理制做了高温超导环流演示仪,该仪器可演示零电阻现象、环流磁场及超导体电阻与温度的关系.