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991.
992.
Ishiguro M Hanada K Liu H Zushi H Yoshida N Tokunaga T Nakamura K Fujisawa A Idei H Sakamoto M Hasegawa M Tashima S Takase Y Maekawa T Kishimoto Y Mitarai O Kawasaki S Nakashima H Higashijima A 《The Review of scientific instruments》2011,82(11):113509
In magnetized plasmas, the presence of a significant number of energetic electrons has been observed but quantitative characteristics of these electrons are proving difficult to investigate. A Langmuir probe offers a means to provide quantitative measurement of these energetic electrons that takes into account electron emissions (secondary electron emission and electron reflection) from the probe tips and sheath expansion around the probe tips caused by a considerable negative potential. In this paper, these effects are experimentally confirmed and an analytical means to measure energetic electron characteristics are proposed. An analysis of plasmas produced by a high frequency wave is then applied leading to the successful detection of an asymmetric flow of energetic electrons. The estimated electron temperature and current density were approximately 4-5 keV and 2-3 kA/m(2). 相似文献
993.
Si and Ge are widely used as analyzing crystals for x-rays. Drastic and accurate shaping of Si or Ge gives significant advance in the x-ray field, although covalently bonded Si or Ge crystals have long been believed to be not deformable to various shapes. Recently, we developed a deformation technique for obtaining strongly and accurately shaped Si or Ge wafers of high crystal quality, and the use of the deformed wafer made it possible to produce fine-focused x-rays. In the present study, we prepared a cylindrical Ge wafer with a radius of curvature of 50 mm, and acquired fluorescent x-rays simultaneously from four elements by combining the cylindrical Ge wafer with a position-sensitive detector. The energy resolution of the x-ray fluorescence spectrum was as good as that obtained using a flat single crystal, and its gain was over 100. The demonstration of the simultaneous acquisition of high-resolution x-ray fluorescence spectra indicated various possibilities of x-ray spectrometry, such as one-shot x-ray spectroscopy and highly efficient wave-dispersive x-ray spectrometers. 相似文献
994.
Internal stress of epoxy resin modified with acrylic polymers having crosslinks produced byin situ UV radiation polymerization 总被引:1,自引:0,他引:1
Yoshinobu Nakamura Miho Yamaguchi Kazuo Iko Masayoshi Okubo Tsunetaka Matsumoto 《Journal of Materials Science》1990,25(6):2711-2716
In order to reduce the internal stress of cured epoxy resin generated by shrinkage in the cooling process from cure temperature to room temperature, two kinds of acrylic polymers were introduced byin situ UV radiation polymerization prior to curing. Polybutyl acrylate (A) and butyl acrylate-monoethylene glycol dimethacrylate copolymer (molar ratio 955) (B) were used as the acrylic polymer. In the A-modified resin, a heterogeneous structure with spherical submicrometre domains were formed. In the B-modified resin, irregularly shaped submicrometre domains in which the microphase separation occurred were observed. The modulus of cured epoxy resin decreased as a result of the modifications, and was lower in the B-modified resin than in the A-modified resin. Therefore the internal stress decreased more effectively in the B-modified resin. 相似文献
995.
Nobuhide Yoneya Hideki Ono Yui Ishii Kazuo Himori Nobukazu Hirai Hironobu Abe Akira Yumoto Norihito Kobayashi Kazumasa Nomoto 《Journal of the Society for Information Display》2012,20(3):143-147
Abstract— An organic thin‐film‐transistor (OTFT) backplane has been fabricated by using a solution‐processed organic semiconductor (OSC) and organic insulators. The OSC, a peri‐xanthenoxanthene derivative, provides a mobility of 0.5 cm2/V‐sec. These organic materials enhance the mechanical flexibility of the backplane. The developed backplane successfully drives a 13.3‐in. flexible UXGA electrophoretic display that can operate when bent at a radius of 5 mm. 相似文献
996.
Development of CZTS-based thin film solar cells 总被引:7,自引:0,他引:7
Hironori Katagiri Kazuo Jimbo Win Shwe Maw Koichiro Oishi Makoto Yamazaki Hideaki Araki Akiko Takeuchi 《Thin solid films》2009,517(7):2455-2605
The low cost, environmental harmless Cu2ZnSnS4 (CZTS)-based thin film solar cells are fabricated by using abundant materials. The CZTS film possesses promising characteristic optical properties; band-gap energy of about 1.5 eV and large absorption coefficient in the order of 104 cm− 1. All constituents of this CZTS film, which are abundant in the crust of the earth, are non-toxic. Therefore, if we can use CZTS film practically as the absorber of solar cells, we will be free from both of the resource saving problem and the environmental pollution.In our CZTS project, CZTS absorber films were prepared by two independent techniques. One is three rf sources co-sputtering followed by annealing in sulfurized atmosphere. The latest conversion efficiency of over 6.7% was achieved by this technique. The other is co-evaporation technique. CZTS films were grown on Si (100) by vacuum co-evaporation using elemental Cu, Sn, S and binary ZnS as sources. XRD patterns indicated that the polycrystalline growth was suppressed and the orientational growth was relatively induced in a film grown at higher temperatures.In this presentation, the development of CZTS-based thin film solar cells will be surveyed. 相似文献
997.
Kazuo Yayoi Masahiko Jinno Rintaro Fujikawa Alexander Baryshev Alexander Khanikaev Kwang‐Ho Shin Hironaga Uchida Mitsuteru Inoue 《IEEJ Transactions on Electrical and Electronic Engineering》2007,2(4):463-467
We fabricated porous alumina templates with a well‐ordered pore array by a pre‐triggered anodization method. The arrangement of pores in the fabricated templates was set by a Ni‐dot stamper. The structure of the templates was analyzed by field emission scanning electron microscopy (FESEM), two‐dimensional Fourier transformation of FESEM images and optical means. It was found that the porous alumina templates have a high‐quality, extended, two‐dimensional hexagonal lattice, which can be used in the fabrication of two‐dimensional magnetophotonic crystals (2D‐MPCs). © 2007 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
998.
Satoshi Haneda Chigusa Ueba Kazuo Eda Masahiko Hayashi 《Advanced Synthesis \u0026amp; Catalysis》2007,349(6):833-835
Imidazole and imidazoline (dihydroimidazole) derivatives can serve as efficient and simple ligands for the palladium‐catalyzed Mizoroki–Heck reaction. Among the imidazole and imidazoline derivatives in our investigations, the 2‐methylimidazoline‐palladium(II) chloride complex exhibited the highest catalytic activity. 相似文献
999.
This study performs the numerical simulation of hydrogen dispersion in a partially open space. The space under investigation measures 2.9 m × 1.22 m × 0.74 m and a leak flow rate of 2 standard cubic feet per minute is assumed. The effects of various roof vent positions and their areas on the ability to recognize the dispersion and accumulation of hydrogen, and its natural ventilation, are shown and discussed. Based on the results, this paper proposes an innovative approach to the sensing-based adaptive risk mitigation control of hydrogen dispersion and accumulation in a partially open space. By adaptively opening roof vents near the leak source, and closing other neighboring roof vents, concentrated hydrogen is exhausted rapidly and efficiently. It is also shown that cases exist where sufficient area of the proposed adaptive roof vent can be determined by the finite-time sensing of hydrogen concentration near the roof. The effects of the delay time of a sensor, and a method to cancel these effects, are also discussed. 相似文献
1000.