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排序方式: 共有497条查询结果,搜索用时 15 毫秒
411.
Yamaki Yuto Sato Yuki Izui Kazuhiro Yamada Takayuki Nishiwaki Shinji Hirai Yoshikazu Tabata Osamu 《Structural and Multidisciplinary Optimization》2018,58(3):1243-1254
Structural and Multidisciplinary Optimization - Deformable mirrors are vital components in fundus imaging modality incorporating adaptive optics systems. The application of precisely controlled... 相似文献
412.
Lujun Pan Yasumoto Konishi Hiroyoshi Tanaka Yoshikazu Nakayama Osamu Suekane Toshikazu Nosaka 《仪器仪表学报》2004,25(Z2)
Carbon nanotubes and nanocoils are expected as the charging materials and electron gun for the imaging devices. It is synthesized for carbon nanocoils with different diameters by the catalytic thermal decomposition of acetylene using iron-indium-tin-oxide catalysts. It is found that the turn-on voltage is decreased by decreasing the average diameter of the grown carbon nanocoils. The turn on voltage of as low as 30 V at the electrodes' gap of 130 μm has been achieved when the coil diameter is decreased to 60 nm. The calculation for the concentration of the electric field on the coil surface has been performed using a finite element method. It is obtained that the strength of electric field around the top ring of a coil is increased with the decrease of the tubular diameter of the coil and has a similar value for that at the tip of a carbon nanotube, suggesting that the efficiency of the field emission from nanocoils would be higher than that from nanotubes. These results can explain the good stability of field emission from carbon nanocoils. 相似文献
413.
Haruo Nakazawa Masaaki Ogino Hideaki Teranishi Yoshikazu Takahashi Hitoshi Habuka 《Materials Science in Semiconductor Processing》2013,16(3):923-927
The behavior of precipitates in a floating zone silicon crystal produced from a Czochralski single-crystal ingot has been studied. Large precipitates of α-Si3N4 crystal, having a dimension of about 2 μm, were formed at the mid-depth in the wafer by annealing at a high temperature in an ambient N2 (70%)+O2 (30%) atmosphere. The number of precipitates detected by cross-sectional X-ray topography increased with increasing annealing time. Because preannealing accompanying silicon oxidation in an ambient Ar+O2 atmosphere prevented the precipitates formation, interstitial silicon is considered to eliminate the origin of precipitate. 相似文献
414.
Chemical Shifts of Silicon X-ray Photoelectron Spectra by Polymerization Structures of Silicates 总被引:1,自引:0,他引:1
Kiyoshi Okada Yoshikazu Kameshima Atsuo Yasumori 《Journal of the American Ceramic Society》1998,81(7):1970-1972
The binding energy of Si 2 p electrons and the kinetic energy of the Si(KLL) X-ray-excited state were measured by using X-ray photoelectron spectroscopy (XPS) and X-ray Auger electron spectroscopy (XAES), respectively, for silicates with SiO4 tetrahedra of various polymerization types. The resulting Si 2 p XPS binding energies varied from 101.3 eV in merwinite (monomeric structure) to 103.4 eV in quartz and cristobalite (three-dimensional framework structure). A clear chemical-shift relation was observed, relating the polymerization structures of SiO4 tetrahedra to the plots of their Si 2 p XPS binding energy versus the kinetic energy of their Si(KLL) XAES spectra. Thus, the structural state of the surface silicates in various substances can be deduced from this chemical-shift relationship. 相似文献
415.
416.
Compact Halo‐Ligand‐Conjugated Quantum Dots for Multicolored Single‐Molecule Imaging of Overcrowding GPCR Proteins on Cell Membranes 下载免费PDF全文
417.
Masaki Kotani Yoshikazu Muta Akinori Yoshimura Shinji Ogihara Tadashi Imai Haruyoshi Katayama Yukari Yui Yoshio Tange Keigo Enya Hidehiro Kaneda Takao Nakagawa 《Journal of Materials Engineering and Performance》2014,23(3):850-858
The Japan Aerospace Exploration Agency has studied large-scale, lightweight mirrors constructed of SiC-based materials as a key technology for future earth observations and astronomical missions. One of the most important technical issues for large-scale ceramic components is their quality stability (viz., differences in material properties depending on the part and the processing), which might influence the structural and/or thermal reliability through unforeseen deformation and breakage. In this study, the authors used a simple, low-cost method for evaluating the properties of SiC mirror materials. Using mechanical testing, thermodilatometry, and microstructural analysis on samples cut from the periphery of a prototype 800-mm-diameter mirror body, the overall quality of the mirror body material was determined. 相似文献
418.
Yoshiki Tsunekawa ;Shinpei Suetsugu ;Masahiro Okumiya ;Naoki Nishikawa ;Yoshikazu Genma 《中国铸造》2014,(4):396-401
For the wider applications,it is necessary to improve the ductility as well as the strength and wear-resistance of hypereutectic AlSi-Cu alloys,which are typical light-weight wear-resistant materials.An increase in the amounts of primary silicon particles causes the modified wear-resistance of hypereutectic Al-Si-Cu alloys,but leads to the poor strength and ductility.It is known that dual phase steels composed of hetero-structure have succeeded in bringing contradictory mechanical properties of high strength and ductility concurrently.In order to apply the idea of hetero-structure to hypereutectic Al-Si-Cu alloys for the achievement of high strength and ductility along with wear resistance,ultrasonic irradiation of the molten metal during the solidification,which is called sono-solidification,was carried out from its molten state to just above the eutectic temperature.The sono-solidified Al-17Si-4Cu alloy is composed of hetero-structure,which are,hard primary silicon particles,soft non-equilibrium a-Al phase and the eutectic region.Rheo-casting was performed at just above the eutectic temperature with sono-solidified slurry to shape a disk specimen.After the rheo-casting with modified sonosolidified slurry held for 45 s at 570 oC,the quantitative optical microscope observation exhibits that the microstructure is composed of 18area%of hard primary silicon particles and 57area%of soft a-Al phase.In contrast,there exist only 5 area%of primary silicon particles and no a-Al phase in rheo-cast specimen with normally solidified slurry.Hence the tensile tests of T6 treated rheo-cast specimens with modified sono-solidified slurry exhibit improved strength and 5%of elongation,regardless of having more than 3 times higher amounts of primary silicon particles compared to that of rheo-cast specimen with normally solidified slurry. 相似文献
419.
420.