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991.
Wang A Ohashi O Yamaguchi N Xie G Song M Furuya K Higashi Y Hitomi N 《Journal of electron microscopy》2004,53(2):157-161
The microstructure at the interface of diffusion-bonded joints of oxygen-free high-conductivity copper for two kinds of surface conditions, with and without argon ion bombardment treatment, was investigated using scanning and high-resolution transmission electron microscopy and energy-dispersive X-ray spectroscopy. The results showed that argon ion bombardment effectively removed the surface oxide film layer and lowered the height of the surface asperity, so that inclusion formation was decreased and void shrinkage time was shortened at the interface of the bonded copper joints, and the tensile strength of diffusion-bonded copper joints was improved obviously. 相似文献
992.
The development of multilayer mirrors for continual use around the K-absorption edge of carbon (4.4 nm) has been begun. Cobalt oxide (Co3O4), silicon oxide (SiO2), and boron nitride (BN) are found to be suitable for multilayer mirrors on the basis of theoretical calculations for wavelengths around the carbon K-absorption edge region. X-ray reflectivity curves with CuKalpha1 x rays of the fabricated Co3O4/SiO2 multilayers have sharp Bragg peaks, and the layer structures evaluated from transmission electron microscopy (TEM) observations are uniform. On the other hand, the Bragg peaks of Co3O4/BN multilayers split, and aggregated Co3O4 is observed. To improve the Co3O4 layer structure, chromium oxide (Cr2O3) was mixed into Co3O4. The mixed oxide layer structure in the Mix/BN multilayer (Mix = Co3O4 + Cr2O3) is relatively uniform, and the Bragg peaks do not split. 相似文献
993.
Yoshinobu Fujishiro Kouich Hamamoto Osamu Shiono Shingo Katayama Masanobu Awano 《Journal of Materials Science: Materials in Electronics》2004,15(12):769-773
Ca doped NiCo2O4 spinel materials were synthesized by conventional solid state reactions at 900 °C. Thermoelectric properties of polycrystalline products were characterized at high temperature range of 800 °C in air. d.c. conductivity of the prepared polycrystalline 5 mol % Ca doped NiCo2O4 was about 60 S m–1 at 300 °C. The value of d.c. conductivity was increased with the temperature increasing. Thermoelectric voltage of polycrystalline Ni1–x
Ca
x
Co2O4 (x=0–0.05) was positive at 300–800 °C, this showed p-type thermoelectric properties. The Seebeck coefficient of 5 mol % Ca doped NiCo2O4 was ca. 300 V/K at 600 °C. The value of the Seebeck coefficient of Ni1–x
Ca
x
Co2O4 polycrystalline products decreased with the increasing temperature. Thermal conductivity of 5 mol % Ca doped NiCo2O4 was ca. 2.2 W m–1 K–1 at 600 °C. The estimated thermoelectric figure-of-merit, Z, of 5 mol % Ca doped NiCo2O4 spinel polycrystalline product was about 3.5×10–5 K–1 at 600 °C. 相似文献
994.
Young-Joon?Yang Osamu?Kadosaka Masahiko?Shibahara Masashi?Katsuki Si-Pom?KimEmail author 《Journal of Mechanical Science and Technology》2004,18(12):2104-2113
Surface degreasing method with premixed flame is proposed as the removal method of adherent impurities on materials. Effects
of adherent molecular thickness and surface potential energy on evaporation rate of adherent molecules and molecular evaporationmechanism
were investigated and discussed in the present study. Evaporation processes of adherent molecules on surface molecules were
simulated by the molecular dynamics method to understand thermal phenomena on evaporation processes of adherent molecules
by using high temperature gas like burnt gas. The calculation system was composed of a high temperature gas region, an adherent
molecular region and a surface molecular region. Both the thickness of adherent molecules and potential parameters affceted
the evaporation rate of adherent molecules and evaporation mechanism in molecular scale. 相似文献
995.
An on-demand mixing droplet spotter for generating and mixing picoliter droplets has been developed for ultrasmall reaction vessels. The droplets were generated by applying a approximately 500-V, approximately 2-ms pulsed voltage to the tips of capillary tubes (o.d. approximately 20 microm; i.d. approximately 12 microm) filled with solution. The mixing process was achieved using electrostatic force. The initial droplet was formed by applying the pulsed voltage between one capillary and the substrate, and the second jet of the other solution was generated from the other capillary and collided with the initial droplet automatically because the electric field lines concentrated on the initial droplet. Using this mixing process, a microarray having a concentration gradient was obtained by spotting approximately 6-pL droplets on a surface with a density of one spot per 75 x 75 microm(2). 相似文献
996.
Hiroaki Mochizuki Harutaka Mekaru Shinji Kusumi Noriaki Sato Masami Shimizu Michiru Yamashita Osamu Shimada Tadashi Hattori 《Microsystem Technologies》2007,13(5-6):547-550
Investigations of microactuators are actively being pursued in various viewpoint, researchers are exploring output energy
sources such as electrostatic, piezoelectric, electromagnetic and etc. We focus attention recently on the electromagnetic
microactuator. In generally, electromagnetic actuator is not well suited to miniaturization because of decreased output force
when miniaturized. However, we have already developed 3D-LIGA process to produce a spiral microcoil in 2003. Then, the production
process of a smaller and higher output force microactuator was devised based on this technology. 相似文献
997.
The cooling temperatures of rectangular parallelepiped Bi1-X
Sb
X
(X = 0.12 and 0.15) single-crystals with the same thickness of t = 2 mm but different width W were measured at 113 K and 290 K as a function of electric current in the magnetic field B up to 2.17 T. The magnetic field was aligned along the thickness t of a sample and the current flows along its length L through the copper leads soldered to both end surfaces of cross section (W × t), where W, t and L are parallel to the binary, bisector and trigonal axes of the single-crystal, respectively. The thermoelement was not in
contact with a heat sink. The cooling temperature of Bi0.85Sb0.15 at 290 K was increased with an increase of B and was almost symmetric for the reverse of the field direction, while at 113 K it exhibited a maximum at B = ±0.25 T and a strong asymmetry for the field direction. The largest maximum cooling temperature ΔT
max of Bi0.85Sb0.15 was achieved when a thermoelement has optimum dimensions so that heat energy is hardly generated at the cold side. When the
single-crystal Bi0.85Sb0.15 alloy has optimum dimensions of L = 15 mm, W = 4 mm and t = 2 mm, the ΔT
max at 290 K increased from 4.2 K in B = 0 T to 9.6 K in B = +2.17 T, so that it exceeded ΔT
max values of 5.7 K obtained for a typical Bi2Te3 and 8.5 K measured previously for Bi single-crystal in B = +2.17 T. 相似文献
998.
The voltage ΔV and electric current ΔI of the p- and n-type Cu/Bi–Te/Cu composite thermoelectric devices were measured as a function of ΔT for four regions of the intrinsic Bi–Te compound, Cu/Bi–Te and Bi–Te/Cu interfaces and Cu/Bi–Te/Cu composite using thermocouples
set at intervals of s = 2 and 6 mm, where the lengths of Bi–Te compound and copper are 4 and 5 mm, respectively. ΔV and ΔI of all regions tended to increase linearly with an increase of ΔT. The resultant α was obtained from the relation ΔV/ΔT. The resultant α values of regions including the interface are much higher in absolute value than those of the intrinsic
Bi–Te compounds, so that the barrier thermo-emf is found to occur in the forward-bias direction. It indicates that the barrier
thermo-emf appears even in the semiconductor-metal junction, as in the case of the p–n junctions. The resultant α of Cu(T
H)/Bi–Te interface rich in the heat flow increases with an increase of ΔT, while that of Bi–Te/Cu(T
C
) interface poor in the heat flow decreases with an increase of ΔT. The ΔT-dependence of α of the interfaces is entirely opposite at the hot and cold sides. As a result, the resultant α of the p-
and n-type Cu/Bi–Te/Cu composites remained little varied with changes of ΔT, so that the present composites have a thermal stability superior to the intrinsic Bi–Te compounds.The generating powers
ΔW
Bi-Te and ΔW
Cu/Bi-Te/Cu for the p- and n-type intrinsic Bi–Te compounds and Cu/Bi–Te/Cu composites increased parabolalically with an increase of
ΔT, and the ratios of ΔW
Cu/Bi–Te/Cu to ΔW
Bi–Te reached great values of 1.41 and 1.45 for the p- and n-type composites, respectively. It was thus found that the enhancement
in the resultant α of the composite materials results in a significant improvement in the conversion efficiency for generators. 相似文献
999.
Hiroshi Watanabe Koki Nishizawa Osamu Takaki 《Electronic Notes in Theoretical Computer Science》2006,164(1):177-194
The Cone of Influence Reduction is a fundamental abstraction technique for reducing the size of models used in symbolic model checking. We develop coalgebraic representations of systems as composites of state transition maps and connectors. These representations include synchronous systems, asynchronous systems, asynchronous systems with synchronization by channels, and those with shared variables, probabilistic synchronous systems and so on. We schematically show the cone of influence reduction using these coalgebraic representations, which give a unified framework for providing the technique for various kinds of systems. 相似文献
1000.
Akira Luc Byungil Jason Alan Venkatram Rajvikram Julieta Andrew Thomas A. Lance Nicholas Maxine Naohide Yukio Masahito Yutaka Masahiko Yoshihiro Osamu 《Future Generation Computer Systems》2006,22(8):876-883
The optical virtual concatenation (OVC) function of The Terabit LAN was demonstrated for the first time at the iGrid 2005 workshop in San Diego, California. The TERAbit-LAN establishes a lambda group path (LGP) for an application where the number of lambdas/L2 connections in a LGP can be specified by the application. Each LGP is logically treated as one end-to-end optical path, so during parallel transport, the LGP channels have no relative latency deviation. However, optical path diversity (e.g. restoration) can cause LGP relative latency deviations and negatively affect quality of service. OVC hardware developed by NTT compensates for relative latency deviations to achieve a virtual bulk transport for the Electronic Visualization Laboratory’s (EVL) Scalable Adaptive Graphics Environment application. 相似文献