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81.
Ziqing Zhai Yuichi Miyahara Hiroshi Abe Yutaka Watanabe 《Metallurgical and Materials Transactions A》2014,45(13):6163-6172
The grain boundary segregation of phosphorus and alloying elements in the heat-affected zone (HAZ) of a low alloy steel was studied quantitatively with atom probe tomography. Non-equilibrium segregation mainly occurred during welding and subsequent fast cooling, leading to remarkable segregation of P, C, Mn, and Mo. The segregation of these four types of solutes showed similar microstructure-dependence at this stage, in which the segregation levels are higher in coarse-grained HAZ and intercritically reheated coarse-grained HAZ than in fine-grained HAZ. After simulated aging, P and Mn showed further enrichment at grain boundaries through equilibrium segregation, while desegregation was observed for C and Mo. In addition, it seems that precipitation of Mo at dislocations was greatly promoted during aging, which probably also contributed to the increase of P and Mn at grain boundaries. 相似文献
82.
Takuya Takahashi Motoya Suzuki Ryuji Nomura Yuichi Okuda Koji Kamiya Takenori Numazawa Peter Shirron 《Microgravity science and technology》2011,23(4):365-372
Superfluid 4He was produced on a small jet plane for the first time using a small GM-refrigerator to condense the liquid and a scroll
pump to get the superfluid by evaporation. The surface wave on superfluid under 0.5g
E, 0.1g
E and 0.05g
E, together with 2g
E and 1g
E, was successfully examined by an optical method utilizing parabolic flight. Here, g
E is the gravitational constant on the ground. Assuming that only the fundamental mode was excited as determined by the sample
cell width, the resonance peak in the frequency domain was well reproduced by the gravity wave with corresponding gravity
constant. 相似文献
83.
Effect of Cation Doping on the Superplastic Flow in Yttria-Stabilized Tetragonal Zirconia Polycrystals 总被引:1,自引:0,他引:1
Junpei Mimurada Manabu Nakano Kazutaka Sasaki Yuichi Ikuhara Taketo Sakuma 《Journal of the American Ceramic Society》2001,84(8):1817-1821
The superplastic characteristics of various cation-doped yttria-stabilized tetragonal zirconia polycrystals (Y-TZP) were examined. For 1 mol% cation doping the true stress of Y-TZP is very dependent on the ionic radii of the doped cations; for instance, smaller cation radii give rise to lower true stress when compared with the other compositions for the same grain size, strain rate, and testing temperature. The altered true stress level must be due to the change in diffusivity of the accommodation process for grain boundary sliding caused by the addition of cations in ZrO2 . The strain to failure of the doped zirconia is affected by both ionic radius and valence of the dopant cations. 相似文献
84.
85.
Shiplu Roy Chowdhury Yuichi Muneyuki Yasunori Takezawa Masahiro Kino-oka Atsuhiro Saito Yoshiki Sawa Masahito Taya 《Journal of Bioscience and Bioengineering》2010,109(3):310-313
The transitional behaviors of myoblasts toward differentiation were investigated in the cultures at the low and high seeding densities (respectively, X0 = 1.0 × 103 and 2.0 × 105 cells/cm2). In the culture at the low seeding density, an increase in confluence degree accompanied a decrease in growth potential (Rp), being Rp = 0.85 and 0.11 at t = 48 and 672 h, respectively. Myoblasts seeded at the high density resulted in the immediate cessation of growth with keeping the low range of Rp = 0.02–0.09 throughout the culture. The reduction of Rp led to the generation of three subpopulations of cells in proliferative, quiescent and differentiated states. Close cell contacts in the confluent state of high seeding culture induced cell quiescence to a higher extent with suppressing differentiation. 相似文献
86.
Katsunori Takeda Tetsuo Hattori Tetsuya Izumi Hiromichi Kawano Shinichi Masuda 《Artificial Life and Robotics》2010,15(4):421-424
Recently, remote monitoring camera systems have been widely used for security. In such systems, one important function is
that the system automatically detects any change in the scenes from the monitoring cameras. In wireless remote monitoring
camera systems, the images of the scenes are generally transmitted as compressed data (e.g., JPEG file), because of the capacity
of the wireless channel. This article shows the automated detection of the change point in time-series data of compressed
JPEG file quantity (Kbytes) from the monitoring camera by applying the sequential probabilistic ratio test (SPRT) and the
Chow test, which is well known as a standard method for detecting structural change in time-series data. 相似文献
87.
Masuda S. Koizumi S. Inoue J. Araki H. 《Industry Applications, IEEE Transactions on》1988,24(5):928-933
The generation of ozone at cryogenic temperatures is investigated with a special interest in increasing the yield of ozone by using low temperatures of liquid natural gas. Two modes of plasma chemical processes are studied, both based on electric discharges: one is the high-frequency surface discharge mode under ordinary gas pressure and at a temperature above the liquid temperature of ozone at this pressure (-111°C); the other is the glow discharge mode under a low gas pressure (0.5-2.0 torr) and low gas temperature (-190°C). The surface discharge mode uses a novel ozonizer developed by the authors made of 92% high-purity alumina and tungsten electrodes sintered together. This ozonizer has an extremely high resistance to large temperature gradients and thermal shock, which is a prerequisite for cryogenic operation. The glow discharge mode uses a Pyrex glow tube with a separate liquid-ozone collector. A dramatic improvement in the energy yield of ozone generation is achieved in both modes of cryogenic operation. The results of preliminary test for cryogenic ozone generation are very encouraging 相似文献
88.
Masuda Senichi Hosokawa Shunsuke Tachibana Naoji Ando Takashi Matsumoto Yoichi 《Industry Applications, IEEE Transactions on》1987,(1):120-126
The fundamental characteristics of the direct-coupled pulse energization in electrostatic precipitators (EP's) are investigated in a test rig comprised of a coal pulverizing facility, a furnace, a gas cooling system, and an EP. The EP consisted of a corona electrode with barbed wires and a collection electrode with 300-mm duct spacing. This simulates the type of EP normally used in a coal-fired power station. The pulse-energized collection field shows a very high collection performance of more than 99 percent collection efficiency and the performance enhancement compared to the conventional dc energization, causing very severe back corona, becomes as large as H = 2.50.H is the enhancement factor in terms of the Deutsch migration velocity in the case of the very high resistivity dust of rd = 2 x 1013 ?cm at the gas temperature of Tg = 150°C. Even at the lower level of the dust resistivity at Tg = 110°C, where no back corona occurs in the dc-energized collection field, the performance enhancement is as large as H = 1.21. The mechanism of such great performance enhancement is likely to be the result of the very uniform and very intense formation of corona plasmas on the wires as a result of the very fast rise in the pulse voltage applied and a special sawtooth waveform of the operating voltage between the corona and collection electrodes. 相似文献
89.
Koga Y Kobayashi K Yang J Nakano H Yamane T 《Journal of Bioscience and Bioengineering》2002,94(1):84-86
A mutant library of Burkholderia cepacia lipase KWI-56 was constructed on microplates by a cell-free process and tested with a chromogenic assay. This high-throughput construction system can be used to screen mutant proteins based on their catalytic activity. 相似文献
90.
Yoshitomo Masuda Norio Nihei Ryo Sakurai Reiji Hattori 《Journal of the Society for Information Display》2006,14(5):443-448
Abstract— A novel reflective display [Quick‐Response Liquid Powder Display (QR‐LPD®)], has been developed. This paper‐like display has the advantages of outstanding image stability, easy viewing, low‐power consumption, and a high‐response time. QR‐LPD® will be promoted, initially, for use as electronic price‐tag displays for merchandise. In addition, QR‐LPD® is suitable for flexible display applications because it does not require TFT arrays or a high‐temperature process while maintaining an excellent paper‐like image as well as glass‐type display compatibility. 相似文献