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981.
Microsystem Technologies - In this paper we propose a MEMS fabrication process that enables a polydimethylsiloxane (PDMS) diaphragm to be integrated with a sputtered thin film permanent magnet...  相似文献   
982.
为实现人和机器人握手运动的同步, 本文提出了一种基于动力学在线更新的智能控制器. 首先, 建立了人和机器人握手的仿真模型; 然后对智能控制器中有任意吸引子的动力学系统进行多项式近似设计和在线更新设计,使其具备自振动特性和输入输出同步特性; 同时通过忘却系数和负荷系数, 输入输出同步程度能实现参数可调; 最后, 将该智能控制器用于人和机器人握手的控制中, 仿真结果表明了该智能控制器设计的有效性.  相似文献   
983.
To screen for autoantibodies associated with systemic lupus erythematosus (SLE), we used proteomic approaches combining 2-D PAGE and Western blot analysis, followed by protein identification by LC-MS/MS analysis, resulting in the identification of aldolase A as a novel autoantigen in SLE. ELISA showed the prevalence of anti-aldolase A antibodies to be 29.3% in SLE, 8.2% in rheumatoid arthritis, 18.1% in polymyositis and absent in healthy controls. Furthermore, 43.4% of SLE patients suffering from nephritis showed anti-aldolase A autoantibodies, which was significantly higher than the prevalence for those without nephritis (11.1%). In lupus nephritis, there are few reliable diagnostic methods, other than urinalysis. Therefore, these results indicate that autoantibodies against aldolase A may serve as an alternative clinical biomarker of SLE associated with nephritis.  相似文献   
984.
Powders of Si3N4, Al2O3 and SiO2 were mixed with Y2O3 as sintering aid and hot-pressed to form o- sialon. During sintering, the o phase preferentially precipitated in the temperature region of 1550 to 1600 °C, and the phase precipitated at temperatures of 1700 °C and above. The resultant microstructure consisted of dual phases of o and . The mechanical properties of o- sialon were improved with increasing amount of the phase. When SiO2 required for the formation of the o phase was all included in the grain boundary phase, o- sialon exhibited a three-point bending strength as much as 1400 MPa. The oxidation resistance of o- sialon is expected to improve due to the presence of the o phase, but actually was not so good due to the presence of the grain-boundary glassy phase and impurities.  相似文献   
985.
This paper considers materials for the movers, the volume ratio of the stator and of the mover, and the structure of the mover in a cylindrical moving iron-type linear oscillatory actuator (LOA) having a permanent magnet. As a result, we obtain the following:
  • (1) the static thrust characteristics are evaluated on two movers: movers P and S are made of a permendur and a stainless steel, respectively. It is clarified that the static thrust of the mover P is 30 percent larger than that of the mover S;
  • (2) it is suggested that the structure of the mover P should be improved to eliminate a “lump” in the static thrust-displacement curve due to the step on the mover, and which disturbs the smooth motion of the LOA.
  相似文献   
986.
The saturated amounts of solubilized cholesterol (Cch) in mixed micelles of sodium cholate (NaC) and octaoxy-ethylene glycol monon-decyl ether (C10E8) and of sodium zyme assay at 25, 29, 33 and 37°C. The Cch values in both systems increase with the total surfactant concentration. Because the mixed micelles for both systems tend to form C10E8-rich micelles near the critical micellar concentration (CMC) of the mixed system, the curves of cholesterol solubility approached the Cch curve for C10E8 alone near the CMC. The tendency of Cch to decrease in both systems with increasing mole fractions of bile salts resembled that of the mean aggregation number of micelles. Thermodynamic analyses of cholesterol solubilization showed that the free energy of solubilization, if considered as the transfer of cholesterol from solid state to micellar environment, increased with increasing mole fraction of bile salt. The enthalpy of cholesterol solubilization (ΔHS→M) decreased with the mole fraction of bile salts and showed break points around the mole fraction of 0.75 for the NaC−C10E8 system and at 0.60 for the NaDC−C10E8 system, respectively. These phenomena resemble earlier hydrophobicity data for mixed micelles by fluorescence measurements. Furthermore, Cch values for the NaDC−C10E8 system were larger than those for the NaC−C10E8 system because of the structural differences at the 7α hydroxyl group between NaC and NaDC. This fact was confirmed by thermodynamic calculations.  相似文献   
987.
Martensitic stabilization caused by deformation in a TiNi shape memory alloy was studied.Special attention was paid to the deformed microstructures to identify the cause of martensitic stabilization.Martensitic stabilization was demonstrated by differential scanning calorimetry for the tensioned TiNi shape memory alloy.Transmission electron microscopy revealed that antiphase boundaries were formed because of the fourfold dissociation of [110]B19' super lattice dislocations and were preserved after reverse t...  相似文献   
988.
We report experiments of the torsional oscillator to observe the superfluid transition in 4 He films in porous glass (the pore diameter is 1m). Stability and reproducibility of the oscillator, which quite often is problematic in previous experiments, is essential for a quantitative analysis of observations in different conditions. It follows that the friction of the superfluid films and the energy dissipation of the solid films are derived from comparisons of measurements for different film thickness.  相似文献   
989.
Summary Both Taylor vortex flows in a symmetric or asymmetric system exhibit various patterns (cell modes). They can be classified by the process of cell formation, the number of cells and the direction of flow for the cell, into primary modes or secondary modes, and normal modes or anomalous modes. Following the previous report in which flows in a symmetric end condition were classified, in the present work, for flows in an asymmetric end condition, the Reynolds number at which a secondary mode bifurcates into another mode is experimentally investigated, and the bifurcation of the Taylor vortex flows in an asymmetric system when the Reynolds number is gradually decreased is presented in a bifurcation diagram.List of symbols R1 Radius of inner cylinder (2R1=40.19±0.006 mm) - R2 Radius of outer cylinder (2R2=60.11±0.024 mm) - D Clearance between cylinders (R2-R1=9.96±0.025 mm) - L Height of working fluid - Aspect ratio=L/D - Rotational angular speed - Kinematic viscosity - Re Reynolds number=R1D/  相似文献   
990.
The magnetic structure of thet-J andt-t-J models are investigated. Assuming that the ground state has magnetic long-range order, we calculated the energy of some magnetically ordered states using a simple transformation of the models and theS approximation. The result shows that the Néel state is destroyed by doped holes unless the next-nearest neighbor hoppingt is finite, and that the ferromagnetic phase appears at moderate doping. Mean field analysis shows that the intermediate phase between the Néel and ferromagnetic phase has spiral spin order, although the spiral phase is shown to be unstable against density fluctuations.On leave from the Department of Materials Science, Faculty of Science, Hiroshima University, Higashi-Hiroshima 724, Japan.  相似文献   
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