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991.
The authors propose a novel slider design. The tri-pad slider has three separate air bearing surfaces, one in the front of the slider and the other two in the back of the slider. This design permits the optimization of the air bearing stiffness and flying attitude without changing the minimum flying height. It can minimize the effect of skew angle on the flying height, and offers ample room for a larger size thin film head element. Samples were fabricated and flying characteristics at several velocities, as well as the dynamic flying stability, were investigated. 相似文献
992.
Takehiko Watanabe Hajime Itoh A. Yanagisawa Makoto Hiraishi 《Welding International》2013,27(9):633-639
In this study, the authors applied the ultrasonic welding method to weld A6061 heat treatable aluminium alloy and investigated the effects of clamping load and welding time on the properties of the weld. In addition, in order to improve the strength of the joint, the effectiveness of the ethanol droplet on the faying surface was examined. The following results were obtained. The joint strength increased with clamping load and welding time. The fracture of the joint produced under the welding conditions of 1176 N clamping load and 1.5 s welding time occurred in the base metal. The ethanol droplet on the faying surface successfully produced the joint with a strength equivalent to that of the base metal under the welding conditions of smaller clamping load and shorter welding time than the case without ethanol droplet. The softening around the welded area that was performed with the ethanol droplet was smaller than that in the welded area produced by other methods such as TIG and friction stir welding. The fracture surface of the joint welded with the ethanol droplet was remarkably irregular and rough. A dimple pattern was observed over a wide area, indicating that the welded area was significantly expanded. The ethanol droplet made the temperature of the weld area higher than that without ethanol, resulting in improved joint strength with an increase of the plastic deformation at the interface. 相似文献
993.
994.
995.
Seung-Jun Yu Makoto Fujimaki Koichi Awazu Kimikazu Sasa 《Nuclear instruments & methods in physics research. Section B, Beam interactions with materials and atoms》2008,266(21):4762-4765
Reduction in polarization dependent loss of a planar lightwave circuit was achieved by asymmetric birefringence formed by ion implantation, in which oxygen ions were implanted along a diagonal of a cross-section of the planar lightwave circuit. The induced birefringence has a slow axis along the line perpendicular to the diagonal. In the present research, a decrease in polarization dependent loss of up to 3.7 dB was obtained, indicating that the method is effective for reducing polarization dependent loss. 相似文献
996.
Shiho Kanou Katsunori Nishimura Makoto Ichikawa Jirou Yoshida Yukoh Sakata Makoto Otsuka 《Drug development and industrial pharmacy》2013,39(7):771-780
In the presence of urea in solid states, the stability of unpulverized homosulfamine hydrate (phase I; UHH) is significantly decreased whereas that of unpulverized homosulfamine anhydrate (UHA) is not. The stability of UHH is decreased slightly more by pulverization (PHH). The major objective of this study was to investigate the effects of urea, dehydration, and pulverization on the stability of homosulfamine in solid states. Binary mixtures of UHH and urea, PHH and urea, and UHA and urea in a ratio of 1:1 (wt/wt) were prepared as physical mixtures and were analyzed by scanning electron microscopy (SEM), powder X-ray diffraction (PXRD), and Fourier transform infrared (FTIR) spectroscopy to study their appearance and structural changes before and after storage. PXRD analysis revealed that physical mixtures comprising UHH and urea and PHH and urea have the same diffraction pattern as that of the mixture of UHA and urea after preparation. The dehydration rate of the crystal water of UHH was accelerated by the presence of urea in addition to pulverization. Moreover, the PXRD patterns of the physical mixtures of UHH/urea and PHH/urea were significantly altered during storage, whereas that of UHA/urea was not, which was consistent with the SEM and FTIR results. The particle shape and appearance of UHH varied significantly as a result of pulverization. The stability of homosulfamine was influenced not only by the presence of urea and dehydration but also by the surface state and particle size of the crystalline form. 相似文献
997.
Noriaki Hirose Yasuhisa Terachi Motohiro Kawafuku Makoto Iwasaki Hiromu Hirai 《Electrical Engineering in Japan》2011,175(2):63-73
This paper presents a novel method of initial value compensation (IVC) with additional input by considering the optimization of control input. IVC has been used to improve the control performance of various control systems with different initial values. Essential subjects, however, have still remained: in the conventional IVC approaches, the increases in the amplitude and number of high‐frequency components of the control input that accompany an increase in the control bandwidth could not be avoided. In this research, therefore, an optimization approach for control input is applied under the constraints of the conventional IVC approach. The effectiveness of the proposed approach has been verified by numerical simulations and experiments using a prototype. © 2011 Wiley Periodicals, Inc. Electr Eng Jpn, 175(2): 63‐73, 2011; Published online in Wiley Online Library ( wileyonlinelibrary.com ). DOI 10.1002/eej.21026 相似文献
998.
Kiyoshi Endo Noriyasu Kaneda Hidenori Waku Makoto Saitoh Nobuyoshi Emori 《乙烯基与添加剂工艺杂志》2001,7(4):177-183
Polymerizations of vinyl chloride (VC) with butyllithium (BuLi) and metallocene catalysts were investigated. In the polymerization of VC with BuLi, the activity for polymerization decreased in the following order; t‐BuLi > n‐BuLi > s‐BuLi. A polymer controlled structurally in the main chain was found to be synthesized from the polymerization of VC with BuLi. The molecular weights of polymers obtained in bulk polymerization were higher than those of polymers obtained in solution. A linear relationship of the Mn of the polymer and the polymer yields was observed. The Mw/Mn of the polymer did not change significantly during polymerization, although the Mw/Mn was around 2. Thermal stability of the polymer obtained with BuLi was higher than that of polymer obtained with radical initiators, as determined by TGA measurements. In the polymerization of VC with Cp*TiX3/MAO (X: Cl and OCH3) catalysts, polymers were obtained with both catalysts, although the rate of polymerization was slow. The Cp*Ti(OCH3)3//MAO catalyst in CH2Cl2 gave higher‐molecular‐weight polymers in a better yield than in toluene. From elemental analysis and the NMR spectra of the polymers, the Cp*Ti(OCH3)3/MAO catalyst gave polymers consisting of repeating regular head‐to‐tail units, in contrast to the Cp*TiCl3/MAO catalyst, which gave polymers having anomalous units. 相似文献
999.
Toshiaki Rokunohe Tatsuro Kato Makoto Hirose Tetsu Ishiguro 《Electrical Engineering in Japan》2010,171(1):19-27
Efforts of designers of gas‐insulated switchgear (GIS) are currently focused on such features as smaller installation area and economical efficiency. Circuit breakers (CB), disconnecting switches (DS), and earthing switches (ES) have been redesigned in more compact configurations. Compactness and light‐weight requirements are applied also to bushings used in GIS. GIS bushings can be divided in three general types: capacitor, gas‐filled, and molded bushings. Requirements of the light weight and the economical efficiency of gas‐filled bushings can be satisfied by improvements in insulation technology. Size reduction can be effectively achieved by moderation of the electric field strength on the outside surface of the hollow insulator in the area of the inner grounded electrode tip. We devised a new inner grounded electrode structure consisting of a cylindrical electrode and a ring electrode supported by column electrodes. This paper describes the effect of reduction of the maximum value of electric field strength on the outside surface of the hollow insulator by a new type of grounded electrode. Then, improvement of insulation performance for electrodes with insulation coating in SF6 gas is described as the composite insulation technology. Finally, the efficiency of these insulation technologies is described by the basic insulation test results of a prototype compact 800‐kV SF6 gas‐filled bushing. © 2010 Wiley Periodicals, Inc. Electr Eng Jpn, 171(1): 19–27, 2010; Published online in Wiley InterScience ( www.interscience. wiley.com ). DOI 10.1002/eej.20898 相似文献
1000.
Ammonium perchlorate (AP)-based composite propellant has been widely used as a solid propellant, but higher burning rates are in demand. We report that crystal-habit-modified AP is an effective oxidizer that increases the burning rates of propellants. The modified APs have a dendritic shape. However, dendritic AP is not convenient to mix and cast in an AP/binder slurry because of its high viscosity. We attempted to prepare a crystal-habit-modified AP with polygon or sphere form. The crystal habit of AP was modified by ethylene glycol such that the intensity of the lattice plane (2 1 0) of the modified AP was remarkably high. The shape was almost hexahedral, and the mean particle diameter was approximately 150 μm. 相似文献