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排序方式: 共有1042条查询结果,搜索用时 31 毫秒
21.
Yoshiaki Ukita Toshifumi Asano Kuniyo Fujiwara Katsuhiro Matsui Masahiro Takeo Seiji Negoro Yuichi Utsumi 《Microsystem Technologies》2008,14(9-11):1573-1579
The advantages of vertical microreactor stack with three-dimensional (3D) structure for immunoassay are discussed. The vertical microreactor stack uses vertical fluid flow operation with multifunctional fluid filters. The multi function of fluid filter is very effective for micromixing and passive valve operation. The mechanism of micromixing is discussed by using computational fluid dynamics (CFD), and we know that the mixing mechanism based on Coanda effect. To evaluate the micromixing performance of fluid filter, we demonstrated enzyme reaction with unique repeat mixing operation. As the results, we proved that the fluid filter has very effective mixing performance. The detection limit, which demonstrated by competition enzyme-linked immunosorvent assay (ELISA), is comparable with recommended detection limit, which suggested by Japanese ministry for the environment. 相似文献
22.
Yuichi Ogawa Nobuyuki Inoue Jifang Wang Takashi Yamamoto Kunihiko Okano 《Journal of Fusion Energy》1995,14(4):353-359
Based on scientific databases adopted for designing ITER plasmas and on the advancement of fusion nuclear technology from the recent R&D program, a low wall-loading DEMO fusion reactor has been designed, where high priority has been given to the early and reliable realization of a tokamak fusion plasma over the cost performance. Since the major radius of this DEMO reactor is chosen to be 10 m, plasma ignition is achievable with a low fusion power of 0.8 GW and an operation period of 4–5 hours is available only with inductive current drive. The low ignition power makes it possible to adopt a first wall with an austenitic stainless steel, for which significant databases and operating experience exists, due to its use in the presence of neutron irradiation in fission reactors. In step with development of advanced materials, a step-wise increase of the fusion power seems to be feasible and realistic, because this DEMO reactor has the potential to produce a fusion power of 5 GW. 相似文献
23.
Yuki Akinaga Tokuhisa Kawawaki Hinano Kameko Yuki Yamazaki Kenji Yamazaki Yuhi Nakayasu Kosaku Kato Yuto Tanaka Adie Tri Hanindriyo Makito Takagi Tomomi Shimazaki Masanori Tachikawa Akira Yamakata Yuichi Negishi 《Advanced functional materials》2023,33(33):2303321
Single-atom (SA) catalysts exhibit high activity in various reactions because there are no inactive internal atoms. Accordingly, SA cocatalysts are also an active research fields regarding photocatalytic hydrogen (H2) evolution which can be generated by abundant water and sunlight. Herein, it is investigated whether 10 transition metal elements can work as an SA on graphitic carbon nitride (g-C3N4; i.e., gCN), a promising visible-light-driven photocatalyst. A method is established to prepare SA-loaded gCN at high loadings (weight of ≈3 wt.% for Cu, Ni, Pd, Pt, Rh, and Ru) by modulating the photoreduction power. Regarding Au and Ag, SAs are formed with difficulty without aggregation because of the low binding energy between gCN and the SA. An evaluation of the photocatalytic H2-evolution activity of the prepared metal SA-loaded gCN reveals that Pd, Pt, and Rh SA-loaded gCN exhibits relatively high H2-evolution efficiency per SA. Transient absorption spectroscopy and electrochemical measurements reveal the following: i) Pd SA-loaded gCN exhibits a particularly suitable electronic structure for proton adsorption and ii) therefore they exhibit the highest H2-evolution efficiency per SA than other metal SA-loaded gCN. Finally, the 8.6 times higher H2-evolution rate per active site of Pd SA is achieved than that of Pd-nanoparticles cocatalyst. 相似文献
24.
Taiju Takahashi Yukihiro Kudoh Yuichi Saito Yoshihiro Aoyagi 《Journal of the Society for Information Display》2023,31(3):101-111
Recently, there has been considerable research on optical devices, such as liquid crystal (LC) lenses and special optical plates, using LCs. In such devices, relatively small LC cells are frequently used, or unique LC orientations are required. As an LC orientation process, we focused on the LC director's orientation induced by the magnetic force line distribution of a small neodymium magnet. We propose a simple method for obtaining radial orientation, which is rather difficult to obtain using the ordinary rubbing method. The initial orientation in the LC cell is a vertical orientation cell with almost zero azimuth anchoring. With the proposed method, the reorientation process is performed with an assisting electric field and a small permanent magnet, unlike the conventional magnetic field orientation process that requires a large electromagnet. Furthermore, a polymer stabilization treatment is used to fix the obtained radial orientation pattern in the LC cell. After the treatment, the applying voltage can control the tilt angle of the director in weak polymer treatment, and a completely fixed orientation pattern can be obtained that in strong. 相似文献
25.
Control of the Metal–Insulator Transition at Complex Oxide Heterointerfaces through Visible Light 下载免费PDF全文
26.
Fumiya Kurokawa Masaya Kishimoto Yuichi Tsujiura Hirotaka Hida Isaku Kanno 《Microsystem Technologies》2016,22(6):1275-1283
In this study, we fabricated multilayer ceramics (MLCs) composed of multilayered Pb(Zr,Ti)O3 (PZT) piezoelectric thin films with internal electrodes and evaluated their dielectric and piezoelectric properties. The stack of PZT ferroelectric layers (550 nm) and SrRuO3 (SRO, 80 nm) electrodes were alternatively deposited on Pt/Ti-coated silicon-on-insulator substrates by radio-frequency magnetron sputtering. The MLCs composed of one, three, and five PZT layers were fabricated by the alternate sputtering deposition of PZT ferroelectric layers and SRO electrodes through the movable shadow mask. The capacitances of MLCs were proportionally increased with the number of PZT layers, while their relative dielectric constants were almost same among the each MLC. The MLCs exhibited symmetric and saturated P–E hysteresis loops similar to the conventional PZT thin films. We estimated that the piezoelectric properties of MLCs by FEM simulation, and confirmed that the effective transverse piezoelectric coefficients (d 31,eff ) increased with the number of PZT layers. The piezoelectric coefficients calculated to be d 31,eff = ?2964 pC/N at 25 PZT layers, which is much higher than those of conventional single-layer piezoelectric thin films. 相似文献
27.
Toshio Ogasawara Yuichi Ishida Takashi Ishikawa Takahira Aoki Toshiyuki Ogura 《Composites Part A》2006,37(12):2236-2240
Helium gas permeability of silicate clay (montmorillonite) particles/epoxy nanocomposites was examined. The incorporation of increasing amounts of montmorillonite particles reduced the helium gas permeability. Based on Fick’s law, gas permeation behavior of the nanocomposite was evaluated. With the increase of montmorillonite loading, gas diffusivity decreased, while gas solubility increased. Helium diffusion behavior is in agreement to the numerical results based on the Hatta–Taya–Eshelby theory. It has been revealed that dispersion of nanoscale platelets in polymer is effective in improving gas barrier property. 相似文献
28.
Fujiyoshi T. Shiratake S. Nomura S. Nishikawa T. Kitasho Y. Arakida H. Okuda Y. Tsuboi Y. Hamada M. Hara H. Fujita T. Hatori F. Shimazawa T. Yahagi K. Takeda H. Murakata M. Minami F. Kawabe N. Kitahara T. Seta K. Takahashi M. Oowaki Y. Furuyama T. 《Solid-State Circuits, IEEE Journal of》2006,41(1):54-62
A single-chip H.264 and MPEG-4 audio-visual LSI for mobile applications including terrestrial digital broadcasting system (ISDB-T / DVB-H) with a module-wise, dynamic voltage/frequency scaling architecture is presented for the first time. This LSI can keep operating even during the voltage/frequency transition, so there is no performance overhead. It is realized through a dynamic deskewing system and an on-chip voltage regulator with slew rate control. By the combination with traditional low power techniques such as embedded DRAM and clock gating, it consumes only 63 mW in decoding QVGA H.264 video at 15 frames/sec and MPEG-4 AAC LC audio simultaneously. 相似文献
29.
Yuichi Miyahara Kiyoshi Matsubara Zenji Horita Terence G. Langdon 《Metallurgical and Materials Transactions A》2005,36(7):1705-1711
The extrusion/equal channel angular pressing (EX-ECAP) processing procedure, in which magnesium-based alloys are subjected
to extrusion followed by ECAP, was applied to a Mg-7.5 pct Al-0.2 pct Zr alloy prepared by casting. Microstructural inspection
showed the EX-ECAP process was effective in reducing the grain size from ∼21 μm after extrusion to an as-pressed grain size of ∼0.8 μm. It is shown through static annealing that these ultrafine grains are reasonably stable up to 473 K, but grain growth occurs
at higher temperatures. Tensile specimens were cut from the billets prepared by EX-ECAP and testing showed these specimens
exhibited superplasticity at relatively low temperatures with maximum elongations up to >700 pct. By processing through EX-ECAP
to a higher imposed strain and thereby increasing the area fraction of high-angle boundaries, it is demonstrated that there
is a potential for achieving high-strain-rate superplasticity.
This article is based on a presentation made at the Symposium entitled “Phase Transformations and Deformation in Magnesium
Alloys,” which occurred during the Spring TMS meeting, March 14–18, 2004, in Charlotte, NC, under the auspices of the ASM-MSCTS
Phase Transformations Committee. 相似文献
30.
Kiyoshi Matsubara Yuichi Miyahara Zenji Horita Terence G. Langdon 《Metallurgical and Materials Transactions A》2004,35(6):1735-1744
Experiments were conducted to evaluate the utility of a new processing procedure developed for Mg-based alloys in which samples
are subjected to a two-step processing route of extrusion followed by equal-channel angular pressing (designated as EX-ECAP).
The experiments were conducted using a Mg-0.6 wt pct Zr alloy and, for comparison purposes, samples of pure Mg. It is shown
that the potential for successfully using ECAP increases in both materials when adopting the EX-ECAP procedure. For the Mg-Zr
alloy, the use of EX-ECAP produces a grain size of ∼1.4 μm when the pressing is undertaken at 573 K. By contrast, using EX-ECAP with pure Mg at 573 K produces a grain size of ∼26
μm. Tensile testing of the Mg-Zr alloy at 523 and 573 K after processing by EX-ECAP revealed the occurrence of significantly
enhanced ductilities with maximum elongations of ∼300 to 400 pct. 相似文献