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81.
The flashover voltage with a backside electrode was found to be lower than that without the backside electrode. Under microsecond pulse voltage application, we describe the characteristics of a creeping discharge developed in the narrow gap with the backside electrode. Using a CCD camera and ultrahigh‐speed camera, we observed the corona extension processes. The lowest flashover voltage was found to be obtained at positive polarity with a SF6 content D = 3%. In the corona extension obtained using an ultrahigh‐speed camera, peculiar differences were observed in the corona extension process. The corona extension increased, and rapid flashover was observed at D = 3%. Using a CCD camera, small coronas were detected from the backside electrode. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 158(2): 31–38, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20431 相似文献
82.
E Yonemochi Y Ueno T Ohmae T Oguchi S Nakajima K Yamamoto 《Canadian Metallurgical Quarterly》1997,14(6):798-803
PURPOSE: The purpose of this study was to characterize the amorphous state of ursodeoxycholic acid (UDCA) samples by using isothermal microcalorimetry, X-ray diffraction, infrared (IR) spectroscopy and solid state carbon 13 nuclear magnetic resonance (13C-NMR) spectroscopy, and to demonstrate the application of the thermal methods (microcalorimetry and differential scanning calorimetry (DSC) for studying the amorphous state and clarifying the dissolution mechanism of UDCA. METHODS: Amorphous UDCA was prepared by grinding and rapid cooling of the melts. The heat of solution of UDCA was measured by an isothermal heat-conduction twin microcalorimeter at 25.0 degrees C. Some physicochemical properties of amorphous UDCA were also studied. RESULTS: The intensities of X-ray diffraction peaks of crystalline UDCA decreased with an increase in grinding time. The heat levels of solution of crystalline UDCA and UDCA ground for 1 min were endothermic, and became exothermic with an increase in grinding time. A good correlation was obtained between the heat of solution and the heat of crystallization determined from the peak area in DSC. Although no significant difference was observed in X-ray diffraction patterns of amorphous UDCA prepared by the two methods, significant differences were recognized in DSC, IR and 13C-NMR, and the heat of solution indicated different values among the two samples. The stability of amorphous UDCA samples stored under 74.5% relative humidity at 40 degrees C was found to depend upon the preparation methods. CONCLUSIONS: Different states of amorphous UDCA were obtained depending on the preparation method. The application of thermal methods to evaluate the amorphous state was demonstrated. The mechanism of dissolution of UDCA was discussed from the results of the heat of solution examination. 相似文献
83.
Okayasu T. Watanabe D. Ono A. Shibata M. Hayase Y. Shirai T. Inoue T. Ueno K. Hosoi F. Akiyama T. 《Lightwave Technology, Journal of》2004,22(9):2064-2082
A protocol-free parallel optical interconnecting module is introduced as a solution to solve memory test system transmission bottlenecks. The optical transmission system flexibly suited for a memory test system is reviewed and discussed. A parallel optical module capable of transmitting from dc to 34.1Gb/s (4.267 Gb/s /spl times/8 ch) has been developed. A data transmission throughput density per unit volume of 19 Gb/s/cm/sup 3/ is achieved. A random jitter of less than 3-ps root-mean-square is also achieved. Furthermore, high-density optical connector, high-density optical fiber cable, fiber guides, and cable management/reinforcement members suited for mechanical requirements of the memory test system have been developed. 相似文献
84.
Nao-Aki Noda Akifumi Inoue Masato Nagawa Fumitaka Shiraishi 《International Journal of Pressure Vessels and Piping》2002,79(12):807-818
This paper deals with a new seal system between flange joints without using a gasket. This gasketless flange includes a groove and an annular lip that is machined in one of the flange rings which when removed being in contact with the other flange to form a seal line when the flanges are assembled. In this study, firstly, fundamental dimensions are examined for unplasticized polyvinyl chloride (PVC-U JIS) to obtain the best sealing performance. Then, the effects of material difference and flange nominal size upon the sealing performance of the new gasketless flange are investigated for two types of materials, 0.25% carbon steel (S25C JIS) and PVC-U. It is found that the critical internal pressure at which leakage appears is mainly controlled by the maximum stress at the annular lip for each material even if the flange nominal sizes are different. The gasketless flange made by PVC-U shows the higher critical internal pressure compared with the case of S25C if the same clamping forces are applied. The effect of stress relaxation for PVC-U on the sealing performance is also considered. Then, it may be concluded that this PVC-U gasketless flange as well as S25C has good sealing performance. 相似文献
85.
T. Watanabe D. E. Melnikov T. Matsugase V. Shevtsova I. Ueno 《Microgravity science and technology》2014,26(1):17-28
An experimental investigation has been performed to study a supercritical flow driven by the combined effects of buoyancy and thermocapillary forces, in a non-isothermal liquid cylindrical column heated from above (liquid bridge). The liquid zone was of 3mm in radius and 2.58mm in height made of n-decane. Changing temperature of air in the experimental chamber via controlling the temperature at its external wall, the conditions at the onset of instability of the flow, as characterized by the critical value of the imposed temperature difference, were determined for several values of the liquid volume. Performing ”chaos analysis” of the obtained data, different regimes of the supercritical flow were identified. The experimental observations are supported by a computer modeling of the thermoconvective flow made for the experimental conditions neglecting deformations of the liquid-gas interface. It is shown that the spatial structure of the flow may change with external conditions in the ambient gas. 相似文献
86.
Keiichirou Yonezawa Alexander Hinderhofer Takuya Hosokai Kengo Kato Rintaro Makino Frank Schreiber Nobuo Ueno Satoshi Kera 《Advanced Materials Interfaces》2014,1(5)
The dependence of the energy level alignment (ELA) on structural defects at an organic/organic heterojunction (OOH) of perfluoropentacene (PFP)‐on‐diindenoperylene (DIP) was investigated using X‐ray scattering and ultraviolet photoelectron spectroscopy. The density of structural defects near the interface between the PFP and DIP layers was varied by changing the growth temperature of the DIP film. A direct relationship was found between the defect density and the ELA at the OOH; the ELA together with the change in the electrostatic potential (quasi‐interface dipole layer) at the OOH varies systematically with the defect density near the interface. This indicates that a key factor affecting the ELA is the electrostatic potential change across the OOH interface, which is produced by electron transfer from DIP occupied gap states to PFP unoccupied gap states. These gap states originate from the defects and are effectively controlled by adjusting the growth conditions of the organic films. As a result, the ELA at OOH interfaces can be controlled by the density of structural defect, which is important for organic devices employing OOHs, such as organic photovoltaic cells. 相似文献
87.
Xiang PH Asanuma S Yamada H Inoue IH Sato H Akoh H Sawa A Ueno K Yuan H Shimotani H Kawasaki M Iwasa Y 《Advanced materials (Deerfield Beach, Fla.)》2011,23(48):5822-5827
A prototype Mott transistor, the electric double layer transistor with a strained CaMnO(3) thin film, is fabricated. As predicted by the strain phase diagram of electron-doped manganite films, the device with the compressively strained CaMnO(3) exhibits an immense conductivity modulation upon applying a tiny gate voltage of 2 V. 相似文献
88.
Ishikawa M Sekine K Okamura A Zheng YW Ueno Y Koike N Tanaka J Taniguchi H 《Journal of Bioscience and Bioengineering》2011,111(6):711-718
Reconstitution of tissue architecture in vitro is important because it enables researchers to investigate the interactions and mutual relationships between cells and cellular signals involved in the three-dimensional (3D) construction of tissues. To date, in vitro methods for producing tissues with highly ordered structure and high levels of function have met with limited success although a variety of 3D culture systems have been investigated. In this study, we reconstituted functional hepatic tissue including mature hepatocyte and blood vessel-like structures accompanied with bile duct-like structures from E15.5 fetal liver cells, which contained more hepatic stem/progenitor cells comparing with neonatal liver cells. The culture was performed in a simulated microgravity environment produced by a rotating wall vessel (RWV) bioreactor. The hepatocytes in the reconstituted 3D tissue were found to be capable of producing albumin and storing glycogen. Additionally, bile canaliculi between hepatocytes, characteristics of adult hepatocyte in vivo were also formed. Apart from this, bile duct structure secreting mucin was shown to form complicated tubular branches. Furthermore, gene expression analysis by semi-quantitative RT-PCR revealed the elevated levels of mature hepatocyte markers as well as genes with the hepatic function. With RWV culture system, we could produce functionally reconstituted liver tissue and this might be useful in pharmaceutical industry including drug screening and testing and other applications such as an alternative approach to experimental animals. 相似文献
89.
Wang L Xiong W Nishijima Y Yokota Y Ueno K Misawa H Qiu J Bi G 《Applied optics》2011,50(28):5600-5605
Ag/Au bimetallic nanoparticles possess the combinatory advantages of Au and Ag nanoparticles and can also be utilized to tune the properties of localized surface plasmon resonance. Ag/Au bilayer nanorods were prepared by electron beam lithography, and their spectral properties were investigated. Compared with Ag monolayer nanorods, Ag/Au bilayer nanorods show broader localized surface plasmon resonance bands, and the longitudinal mode and transverse mode localized surface plasmon bands show blueshift and redshift, respectively. The maximum near-field intensity of the longitudinal mode of the Ag/Au nanorod is less than half that of the Ag/Au nanorod without gold layer. Shape-induced modification of Ag/Au bilayer nanorods on their spectral properties was also discussed. 相似文献
90.
Kameyama S Imaki M Hirano Y Ueno S Kawakami S Sakaizawa D Kimura T Nakajima M 《Applied optics》2011,50(14):2055-2068
A feasibility study is carried out on a 1.6 μm continuous-wave modulation laser absorption spectrometer system for measurement of global CO(2)concentration from a satellite. The studies are performed for wavelength selection and both systematic and random error analyses. The systematic error in the differential absorption optical depth (DAOD) is mainly caused by the temperature estimation error, surface pressure estimation error, altitude estimation error, and ON wavelength instability. The systematic errors caused by unwanted backscattering from background aerosols and dust aerosols can be reduced to less than 0.26% by using a modulation frequency of around 200 kHz, when backscatter coefficients of these unwanted backscattering have a simple profile on altitude. The influence of backscattering from cirrus clouds is much larger than that of dust aerosols. The transmission power required to reduce the random error in the DAOD to 0.26% is determined by the signal-to-noise ratio and the carrier-to-noise ratio calculations. For a satellite altitude of 400 km and receiving aperture diameter of 1 m, the required transmission power is approximately 18 W and 70 W when albedo is 0.31 and 0.08, respectively; the total measurement time in this case is 4 s, which corresponds to a horizontal resolution of 28 km. 相似文献