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31.
Sun-Chan Jeong Ichiro Katayama Hirokane Kawakami Yutaka Watanabe Hironobu Ishiyama Nobuaki Imai Yoshikazu Hirayama Hiroari Miyatake Masao Sataka Satoru Okayasu Hiroyuki Sugai Shin-Ichi Ichikawa Katsuhisa Nishio Shinichi Mitsuoka Takamitsu Nakanoya Masahito Yahagi Takanori Hashimoto Kazunori Takada Mamoru Watanabe Tomoko Ishikawa Akihiro Iwase 《Journal of Phase Equilibria and Diffusion》2005,26(5):472-476
For the effective use of short-lived radioactive beams, soon to be available at the Tokai Radioactive Ion Accelerator Complex, the authors have developed a radiotracer method for diffusion studies in solids. The experimental test was performed by the measurement of the diffusion coefficients of Li in a sample of the compound βLiAl using an α-emitting radiotracer of 8Li (T1/2=0.84 s). It was found that the time-dependent yields of the α particles from the diffusing 8Li that was initially implanted in the sample could be used as a measure of the diffusivity of the tracer in a nondestructive way. The method was applied to measure the self-diffusion coefficients of Li in βLiGa, and for investigating how the Li diffusion in the Li ionic conductors is affected by the concentration of atomic defects (i.e., the existence of the atomic vacancies of Li and the defects in Ga sites that are replaced by Li). 相似文献
32.
Tanaka Takanori; Miwa Naofumi; Kawamura Satoru; Sohma Hitoshi; Nitta Katsutoshi; Matsushima Norio 《Protein engineering, design & selection : PEDS》1999,12(5):395-405
P26olf from olfactory tissue of frog, which may be involvedin olfactory transduction or adaptation, is a Ca2+-binding proteinwith 217 amino acids. The p26olf molecule contains two homologousparts consisting of the N-terminal half with amino acids 1109and the C-terminal half with amino acids 110217. Eachhalf resembles S100 protein with about 100 amino acids and containstwo helixloophelix Ca2+-binding structural motifsknown as EF-hands: a normal EF-hand at the C-terminus and apseudo EF-hand at the N-terminus. Multiple alignment of thetwo S100-like domains of p26olf with 18 S100 proteins indicatedthat the C-terminal putative EF-hand of each domain containsa four-residue insertion when compared with the typical EF-handmotifs in the S100 protein, while the N-terminal EF-hand ishomologous to its pseudo EF-hand. We constructed a three-dimensionalmodel of the p26olf molecule based on results of the multiplealignment and NMR structures of dimeric S100B(ßß)in the Ca2+-free state. The predicted structure of the p26olfsingle polypeptide chain satisfactorily adopts a folding patternremarkably similar to dimeric S100B(ßß). Each domainof p26olf consists of a unicornate-type four-helix bundle andthey interact with each other in an antiparallel manner formingan X-type four-helix bundle between the two domains. The twoS100-like domains of p26olf are linked by a loop with no sterichindrance, suggesting that this loop might play an importantrole in the function of p26olf. The circular dichroism spectraldata support the predicted structure of p26olf and indicatethat Ca2+-dependent conformational changes occur. Since theC-terminal putative EF-hand of each domain fully keeps the helixloophelixmotif having a longer Ca2+-binding loop, regardless of the four-residueinsertion, we propose that it is a new, novel EF-hand, althoughit is unclear whether this EF-hand binds Ca2+. P26olf is a newmember of the S100 protein family. 相似文献
33.
This work focuses on the Hall mobilities (μ) of Al-doped ZnO (Al-ZnO) and Ga-doped ZnO (Ga-ZnO) polycrystals. Their Hall mobilities show opposite behavior as a function of the carrier concentration (n). The potential barrier of Al-ZnO is responsible for the positive dependence in the plot of μ vs. n, while the negative slope observed in Ga-ZnO suggests scattering dominated by charged defects. The near-band-edge photoluminescence (UV, 375 nm) as a function of carrier concentration shows higher photoluminescence for Ga-ZnO compared with Al-ZnO, which also implies a larger potential-barrier effect for Al-ZnO. Such a distinctive difference in the potential-barrier effect also reasonably explains the dissimilarity in the temperature dependence of the electrical resistivity of the samples, demonstrating the control of carrier transport through the potential barrier by dopant for ZnO polycrystals. 相似文献
34.
Takanori Takeno Toshifumi Sugawara Hiroyuki Miki Toshiyuki Takagi 《Diamond and Related Materials》2009,18(5-8):1023-1027
Tribological properties of a diamond-like carbon (DLC) coating with an adhesive tungsten-containing DLC (W-DLC) layer were investigated. The coatings were deposited onto AISI316L steel substrates and Si wafers using plasma enhanced chemical vapor deposition and tungsten co-sputtering of the metal target. Methane and argon gases were used as the precursor of the coatings. In this study, three types of coatings were evaluated: DLC/W-DLC on AISI316L (DLC-1), DLC/W-DLC on Si wafer (DLC-2), and DLC on Si wafer (DLC-3). The structural characterizations were performed by transmission electron microscopy and tapping mode atomic force microscopy. At the boundary between the W-DLC layer and the AISI316L substrate, microscopic decohesion or delamination was not observed. The surface roughness of the DLC-1 coating was greater than that of the DLC-2 coating. This feature was derived from the surface roughness of the initial surface of the AISI316L substrate. Friction tests were performed using a rotation-type ball-on-flat configuration tribometer. The observed friction of the DLC-1 coating was unstable compared with the DLC-2 or DLC-3 coatings. This was due to wear debris which had risen to the friction surface resulting in unstable friction on the DLC-1 coating. During the friction studies, the top DLC layer was removed from the adhesive W-DLC layer because the adhesive strength at this part was not enough. In order to achieve the low and stable friction of the DLC coating with the W-DLC layer on AISI316L, it is necessary to improve the smoothness of the surface and the adhesion between the DLC coating and the W-DLC layer. 相似文献
35.
Takanori Isobe Taku Takaku Tadayuki Kitahara Hideo Sumitani Ryuichi Shimada 《Electrical Engineering in Japan》2009,169(4):65-74
This paper proposes a power supply suitable for driving linear induction motors. The power supply consists of a voltage source inverter (VSI) and a magnetic energy recovery switch (MERS). Circuit configuration and operation principles of the power supply are described. Power factor correction by MERS can increase the output power. Technical advantages of using MERS compared with increasing the rated voltage of VSI are discussed. Some experiments with a linear induction motor were conducted. The results confirm that MERS can reduce the capacity of the VSI or increase the output with the same VSI capacity. The number of devices and magnitude of losses are evaluated on a large‐scale drive system. A half‐bridge type of MERS is provided and discussed. The half‐bridge MERS mitigates disadvantages of using MERS. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 169(4): 65–74, 2009; Published online in Wiley InterScience ( www.interscience. wiley.com ). DOI 10.1002/eej.20832 相似文献
36.
Studies on toxicity of multi-walled carbon nanotubes on Arabidopsis T87 suspension cells 总被引:1,自引:0,他引:1
The possible toxicities of agglomerates of multi-walled carbon nanotubes (MWCNTs) toward plant cells were evaluated. Arabidopsis T87 suspension cells were used as the model cells and decreases in values of cell dry weights, cell viabilities, cell chlorophyll contents, and superoxide dismutase (SOD) activities were seen for the cells cultured in media containing the agglomerates of MWCNTs, indicating the agglomerates of MWCNTs are toxic to the Arabidopsis T87 suspension cells. Moreover, the toxicities increased sharply as the diameters of the agglomerates of the MWCNTs became smaller. A concept based on the hypersensitive response is suggested to explain the possible toxic mechanism induced by the MWCNTs. 相似文献
37.
A secure optical storage based on a configuration of a joint transform correlator by use of a photorefractive material is presented. A key code designed through the use of an optimized algorithm so that its Fourier transform has a uniform amplitude distribution and a uniformly random phase distribution is introduced. Original two-dimensional data and the key code are placed side-by-side at the input plane. Both of them are stored in a photorefractive material as a joint power spectrum. The retrieval of the original data can be achieved with the same key code. We can record multiple two-dimensional data in the same crystal by angular multiplexing and/or key code multiplexing. 相似文献
38.
Yoshinobu Lshii Takanori Nagasaki Naoki Igawa Hitoshi Watanabe Hideo Ohno 《Journal of the American Ceramic Society》1991,74(9):2324-2326
Temperature dependence of the Raman spectrum of lithium oxide single crystal has been measured over a temperature range of 80 to 1073 K. The frequency shift and the line width of the Raman spectrum in lithium oxide were about 531 and 4.5 cm-1 at 80 K, respectively. At 1073 K, the frequency shift and the line width attained the values of 464 and 112 cm-1 , respectively. The strong temperature dependence of the frequency shift and line width was compared with data from some crystals with a fluorite structure. 相似文献
39.
Mikio Enoeda Hisashi Tanigawa Takanori Hirose Satoshi Suzuki Kentaro Ochiai Chikara Konno Yoshinori Kawamura Toshihiko Yamanishi Tsuyoshi Hoshino Masaru Nakamichi Hiroyasu Tanigawa Koichiro Ezato Yohji Seki Akira Yoshikawa Daigo Tsuru Masato Akiba 《Fusion Engineering and Design》2012,87(7-8):1363-1369
The development of a Water Cooled Ceramic Breeder (WCCB) Test Blanket Module (TBM) is being performed as one of the most important steps toward DEMO blanket in Japan. For the TBM testing and evaluation toward DEMO blanket, the module fabrication technology development by a candidate structural material, reduced activation martensitic/ferritic steel, F82H, is one of the most critical items from the viewpoint of realization of TBM testing in ITER. In Japan, fabrication of a real scale first wall, side walls, a breeder pebble bed box and assembling of the first wall and side walls have succeeded. Recently, the real scale partial mockup of the back wall was fabricated. The fabrication procedure of the back wall, whose thickness is up to 90 mm, was confirmed toward the fabrication of the real scale back wall by F82H. Important key technologies are almost clarified for the fabrication of the real scale TBM module mockup. From the view point of testing and evaluation, development of the technology of the blanket tritium recovery, development of advanced breeder and multiplier pebbles and the development of the blanket neutronics measurement technology are also performed. Also, tritium production and recovery test using D-T neutron in the Fusion Neutronics Source (FNS) facility has been started as the verification test of tritium production performance. This paper overviews the recent achievements of the development of the WCCB TBM in Japan. 相似文献
40.
Lili Jiang Xiong Lu Yang Leng Shuxin Qu Bo Feng Jie Weng Fumio Watari 《Materials science & engineering. C, Materials for biological applications》2012,32(4):742-748
This study focused on the effects of microgrooved TiO2 surfaces on osteoblast behavior. Microgrooved TiO2 surfaces with different widths (12 μm and 40 μm) and flat surfaces were fabricated on glass substrates based on the combination of a sol–gel technique and soft-lithography. Osteoblasts (MC3T3-E1) were cultured on the as-prepared microgrooved and flat TiO2 surfaces. Optical microscopy and scanning electron microscopy were used to analyze the adherent cell behavior by examining the cell morphology. Orientation angle analysis indicated that the cells tended to align along the microgrooves. This tendency was stronger on the microgrooves with smaller widths and became weak with increasing width. Alamar Blue assay indicated that the microgrooves restricted cell proliferation and the alkaline phosphatase assay revealed that the microgrooves limited the differentiation rate. This restriction increased with decreasing microgroove width. The surface energy of the TiO2 surfaces was size-dependent and followed the order γ 12 μm < γ 40 μm < γ flat surfaces. Osteoblast proliferation and differentiation on the surface with high surface energy exhibited high proliferation and differentiation rates. These results indicated that surface energy appeared to be a dominant factor for cell activity. Thus, surface energy would be a valuable index for the cell compatibility of a micropatterned surface. 相似文献