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排序方式: 共有3109条查询结果,搜索用时 15 毫秒
991.
Akira Okada Yasuhiro Okamoto Adam Clare Yoshiyuki Uno 《The International Journal of Advanced Manufacturing Technology》2014,70(5-8):1515-1521
In compression or injection molding of rubber products, small pieces of residual rubber often remain on the metal mold surface after releasing the product. This is caused by excessive localized adhesion to the mold surface. Therefore, cleaning of metal mold surface must be often performed, which results in longer molding cycle time, and the lifetime of metal mold is often reduced. In this study, the separation forces between molded rubber and metal mold surfaces are measured with a tensile tester to evaluate the releasability of molded rubber from the metal mold surface. Mold surfaces treated by various surface coatings and surface modification methods including EB polishing were tested and compared. Experimental results show that the separation force between molded rubber and metal mold surfaces depends on the true contact area between them and the chemical composition of the metal mold surface. The separation force decreases with a decrease in contact area. The chromium content at the metal mold surface significantly reduces the separation force. EB polishing is one of the most effective surface treatments for metal molds since the real contact area can be decreased while also decreasing the surface roughness of the tool surface in a short time. Electron beam melting is also shown to be an effective method of distributing chromium uniformly on the metal mold surface. 相似文献
992.
Rosmarinic acid exerts an antiosteoporotic effect in the RANKL‐induced mouse model of bone loss by promotion of osteoblastic differentiation and inhibition of osteoclastic differentiation 下载免费PDF全文
993.
Akira Wada Takeshi OgakiMasahito Niibe Masahito TagawaHidetoshi Saitoh Kazuhiro KandaHaruhiko Ito 《Diamond and Related Materials》2011,20(3):364-367
Hydrogenated amorphous silicon carbide (a-SiCx:H) films were prepared by the decomposition of tetramethylsilane (TMS) with microwave discharge flow of Ar. When radio-frequency (RF) bias voltage (− VRF) was applied to the substrate, the film hardness increased as (2.39 ± 1.12)-(9.15 ± 0.55) GPa for − VRF = 0-100 V. The a-SiCx:H films prepared under various − VRF conditions were analyzed by the carbon-K near edge X-ray absorption fine structure (NEXAFS), by the elastic recoil detection analysis (ERDA), and by the X-ray photoelectron spectroscopy (XPS). From a quantitative analysis of NEXAFS, the sp2/(sp2+ sp3) ratios of C atoms were evaluated as 67.9 ± 2.0, 55.4 ± 2.7, and 51.7 ± 0.7% for − VRF = 0, 60, and 100 V, respectively. From ERDA, hydrogen content of the film prepared under the condition of − VRF = 100 V was found to decrease 28% comparing with that under − VRF = 0 V. It is suggested that the cause of the increase of the film hardness when applying − VRF is predominantly the growth of the sp3-hybridized structure of C atoms accompanied by the decrease of hydrogen terminations. 相似文献
994.
Akira Yoshimura T. Nicholas Jones Mekhman S. Yusubov Viktor V. Zhdankin 《Advanced Synthesis \u0026amp; Catalysis》2014,356(16):3336-3340
An efficient synthetic procedure for dicyano‐cyclopropanation of alkenes using catalytic amounts of molecular iodine as a precatalyst and tert‐butyl hydroperoxide (TBHP) as a terminal oxidant under mild conditions has been developed. This catalytic reaction works especially well for the aryl‐substituted double bond affording products of cyclopropanation in high yields. A catalytic cycle based on the generated in situ hypoiodite species has been proposed.
995.
A novel hetero-junction Tunnel-FET using Semiconducting silicide–Silicon contact and its scalability
Yan Wu Hiroyuki Hasegawa Kuniyuki Kakushima Kenji Ohmori Takanobu Watanabe Akira Nishiyama Nobuyuki Sugii Hitoshi Wakabayashi Kazuo Tsutsui Yoshinori Kataoka Kenji Natori Keisaku Yamada Hiroshi Iwai 《Microelectronics Reliability》2014
A new type of silicon-based Tunneling FET (TFET) using semiconducting silicide Mg2Si/Si hetero-junction as source-channel structure is proposed and the device simulation has been presented. With narrow bandgap of silicide and the conduction and valence band discontinuous at the hetero-junction, larger drain current and smaller subthreshold swing than those of Si homo-junction TFET can be obtained. Structural optimization study reveals that low Si channel impurity concentration and the alignment of the gate electrode edge to the hetero-junction lead to better performance of the TFET. Scaling of the gate length increases the off-state leakage current, however, the drain voltage (Vd) reduction in accordance with the gate scaling suppresses the phenomenon, keeping its high drivability. 相似文献
996.
Sanjay K. Behura Qiaoqin Yang Akira Hirose Omkar Jani Indrajit Mukhopadhyay 《Journal of Materials Science》2014,49(10):3592-3597
A new process has been developed to grow silicon (Si) nanowires (NWs), and their growth mechanisms were explored and discussed. In this process, SiNWs were synthesized by simply oxidizing and then reducing Si wafers in a high temperature furnace. The process involves H2, in an inert atmosphere, reacts with thermally grown SiO2 on Si at 1100 °C enhancing the growth of SiNWs directly on Si wafers. High-resolution transmission electron microscopy studies show that the NWs consists of a crystalline core of ~25 nm in diameter and an amorphous oxide shell of ~2 nm in thickness, which was also supported by selected area electron diffraction patterns. The NWs synthesized exhibit a high aspect ratio of ~167 and room temperature phonon confinement effect. This simple and economical process to synthesize crystalline SiNWs opens up a new way for large scale applications. 相似文献
997.
Grégory Lalet Hiroki Kurita Jean-Marc Heintz Guillaume Lacombe Akira Kawasaki Jean-François Silvain 《Journal of Materials Science》2014,49(1):397-402
Fully dense carbon fiber-reinforced copper and aluminum matrix (Cu–CF and Al–CF) composites were fabricated by hot press without the need for an interfacial chemical compound. With 30 vol% carbon fiber, the thermal expansion coefficients (TECs) of pure Cu and Al were decreased to 13.5 × 10?6 and 15.5 × 10?6/K, respectively. These improved TECs of Cu–CF and Al–CF composites were maintained after 16 thermal cycles; moreover, the TEC of the 30 vol% Cu–CF composite was stable after 2500 thermal cycles between ?40 and 150 °C. The thermal strain caused by the TEC mismatch between the matrix and the carbon fiber enables mechanical enhancement at the matrix/carbon fiber interface and allows conservation of the improved TECs of Cu–CF and Al–CF composites after thermal cycles. 相似文献
998.
Kunchaya Pruethiarenun Toshihiro Isobe Sachiko Matsushita Jinhua Ye Akira Nakajima 《Materials Chemistry and Physics》2014
Two tungsten-based Keggin-type heteropolyacids (PW12: ([PW12O40]3−) and SiW12: ([SiW12O40]4−)) were hybridized with brookite-type TiO2. Then photocatalytic decomposition activity, photoinduced hydrophilicity, and sustainability of the hydrophilicity in the dark were evaluated using gaseous 2-propanol (IPA) decomposition and sessile drop method. The obtained films were transparent in the visible wavelength range. Both hybrid films exhibited higher photocatalytic decomposition activity and had higher photoinduced hydrophilicizing rates than pure brookite films under UV illumination. The PW12/TiO2 film exhibited better photocatalytic performance than the SiW12/TiO2 film did. Atmosphere dependence, XPS analysis, and electrochemical experiments indicated the cause of these two films' different levels of sustainability of hydrophilicity to be differences in their electron storage capability. Results show that the electron scavenger capability and reoxidation efficiency of the heteropolyacid are key factors affecting the overall performance of wettability conversion of this hybrid film system before and after UV illumination. 相似文献
999.
Yuhei Oi Tomohisa Nagoshi Haruka Kimura Yoshiro Tanaka Akira Yoshii Rei Yasutake Hirotake Takahashi Yusuke Kashiwagi Toshikazu D. Tanaka Toshiaki Tachibana Michihiro Yoshimura 《International journal of molecular sciences》2022,23(15)
Increasing evidence suggests natriuretic peptides (NPs) coordinate interorgan metabolic crosstalk. We recently reported exogenous ANP treatment ameliorated systemic insulin resistance by inducing adipose tissue browning and attenuating hepatic steatosis in diet-induced obesity (DIO). We herein investigated whether ANP treatment also ameliorates myocardial insulin resistance, leading to cardioprotection during ischemia–reperfusion injury (IRI) in DIO. Mice fed a high-fat diet (HFD) or normal-fat diet for 13 weeks were treated with or without ANP infusion subcutaneously for another 3 weeks. Left ventricular BNP expression was substantially reduced in HFD hearts. Intraperitoneal-insulin-administration-induced Akt phosphorylation was impaired in HFD hearts, which was restored by ANP treatment, suggesting that ANP treatment ameliorated myocardial insulin resistance. After ischemia–reperfusion using the Langendorff model, HFD impaired cardiac functional recovery with a corresponding increased infarct size. However, ANP treatment improved functional recovery and reduced injury while restoring impaired IRI-induced Akt phosphorylation in HFD hearts. Myocardial ultrastructural analyses showed increased peri-mitochondrial lipid droplets with concomitantly decreased ATGL and HSL phosphorylation levels in ANP-treated HFD, suggesting that ANP protects mitochondria from lipid overload by trapping lipids. Accordingly, ANP treatment attenuated mitochondria cristae disruption after IRI in HFD hearts. In summary, exogenous ANP treatment ameliorates myocardial insulin resistance and protects against IRI associated with mitochondrial ultrastructure modifications in DIO. Replenishing biologically active NPs substantially affects HFD hearts in which endogenous NP production is impaired. 相似文献
1000.