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排序方式: 共有252条查询结果,搜索用时 31 毫秒
221.
ZnO thin films were deposited on nesa silica glass substrates via sol-gel method using Zn(CH3COO)2·2H2O—Co(CH3COO)2 ·4H2O—polyvinylpyrrolidone (PVP)—diethanolamine—2-methoxyethanol solutions. The effects of the Co2+ ions and PVP in coating solutions on the photoanodic properties of the resultant films were studied by measuring photocurrent—potential curves and action spectra in a three-electrode cell with a supporting electrolyte of pH = 9.18. The photoanodic current under xenon lamp light decreased with increasing amount of Co2+ ions due to the decreased quantum efficiency in the UV regions. The photoresponse was extended to wavelengths of ca. 450 nm when the Co/Zn mole ratios were 0.05 and 0.15, while the response to the visible light diminished at Co/Zn > 0.3. The UV photoresponse of Co2+-free ZnO films increased when PVP was added in the coating solutions, where the maximum quantum yield of 0.62 was obtained at a wavelength of 364 nm. On the other hand, the UV photoresponse rather decreased when PVP was added in Co2+-containing solutions. 相似文献
222.
K Imanaka A Furuse T Murakawa J Nakajima Y Kozuka K Yagyu 《Canadian Metallurgical Quarterly》1997,50(13):1101-1103
The patient was 22-year-old female. She had undergone aortic valve replacement and Manouguian's anulus enlargement with low porosity woven Dacron patch for congenital aortic stenosis 13 years ago, and developed mitral regurgitation 9 years after that operation. Two regurgitant flow were observed. One was originated from the orifice due to mitral prolapse. The other was from a tear in the anterior leaflet. It was around the tip of the prosthetic patch, approximately 7 mm in size, and was repaired easily. But the mitral valve itself was found to be malformed and prolapsed, requiring mitral valve replacement. Her postoperative course was uneventful. 相似文献
223.
224.
Shinya Yao Yoichi Kaku Zensaku Kozuka 《Metallurgical and Materials Transactions B》1986,17(1):171-177
Activity coefficient of oxygen, γo, in copper-tellurium melts was determined at 1423 K utilizing a modified coulometric titration technique with the following
electrochemical cell: O in Cu-Te melts/ZrO2(+CaO)/air, Pt. The γo values in the vicinity ofN
Te = 0.30 are much smaller than those in the tellurium-dilute copper-tellurium melts, and increase rapidly with the tellurium
composition. The shape of the In γo
vs solvent composition curve is quite similar to that in Cu-S and Tl-Te melts. This type of compositional dependence can be
successfully described by a proposed solution model.
Formerly Graduate Student, Osaka University 相似文献
225.
Nakagawa Yasuhito Waku Keizo Hirose Akihiko Kawashima Yoichi Kozuka Hiroshi 《Lipids》1986,21(10):634-638
The effect of administeringp-chlorophenoxyisobutyric (clofibric) acid to rats on the molecular species composition of diacyl-glycerophosphocholine (GPC)
of rat liver microsomes was studied. Microsomal choline glycerophospholipids were converted to 1,2-diradyl-3-acetylglycerol
and were separated into molecular species by reverse-phase high performance liquid chromatography. Diacyl-GPC consisted of
17 different molecular species. The predominant species were arachidonoyl derivatives, such as 18∶0–20∶4 (22.2% of the total)
and 16∶0–20∶4 (22.0%). Administration of clofibric acid to rats caused a marked increase in 16∶0–18∶1 species of diacyl-GPC
from 8% to 30%, making these the predominant species of diacyl-GPC in clofibric acid-fed rats. Also, a significant decrease
(50% of controls) in 18∶0–18∶2 and 18∶0–20∶4 species was observed, whereas the decrease in molecular species containing 16∶0
at the 1-position such as 16∶0–18∶2 and 16∶0–20∶4 was small (approximately 85% of control). The results show that clofibric
acid caused marked changes in the molecular species composition of diacyl-GPC. The participation of 1-acyl-GPC acyltransferase
and stearoyl-CoA desaturase in the regulation of the molecular species composition of diacyl-GPC is discussed. 相似文献
226.
Shinya Otsuka Masami Matsuyama Zensaku Kozuka 《Metallurgical and Materials Transactions B》1978,9(1):21-24
The oxygen diffusivity in liquid copper-lead alloys at 1403 K (1130° C) was measured using the electrochemical cell: Ni−NiO/ZrO2(+CaO)/O in liquid Cu−Pb alloy(I)/ZrO2(+CaO)/O in liquid Cu−Pb alloy (II). Oxygen in liquid Cu−Pb alloy (I) was transferred to the right by applying a preselected voltage
between the two liquid Cu−Pb alloys. The oxygen diffusivity in liquid Cu−Pb alloy(I) was calculated from the emf change with
time between the Ni−NiO and liquid Cu−Pb alloy (I) electrodes. The results were:
It was found that the oxygen diffusivity in liquid copper-lead alloys did not change drastically over the entire composition
range, in contrast with that reported by other investigators for liquid copper-nickel alloys. The oxygen diffusivity in pure
liquid lead agreed with the results of our previous work using an FeO−Fe3O4 mixture as a sink for oxygen. 相似文献
227.
Kazuhiko Ikegami Yoshiaki Kawashima Hirofumi Takeuchi Hiromitsu Yamamoto Nobuyuki Isshiki Den-ichi Momose Kiyohisa Ouchi 《Powder Technology》2003,130(1-3):290-297
Spherical agglomerates of steroid KSR-592, consisting of fine primary drug crystals suitable for dry powder inhalation (DPI), were prepared by the spherical agglomeration method in liquid with a bridging liquid. It was found that the particle size of primary crystals increased until the dispersing medium was saturated with the bridging liquid, whereas the spherical agglomeration of primary crystals was continued even after the saturation of medium with the bridging liquid. The growth rates of primary crystals and agglomerates increased with an increase in the temperature and/or a reduction in the agitation speed of the system. The agglomerates were easily disintegrated into the primary crystals depositing ideally on carrier lactose particles for DPI by mixing. The in vitro efficiency of the mixed system of lactose and disintegrated primary crystals of drug was 2 to 3 times higher than that of crystals prepared conventionally. Furthermore, the soft agglomerates disintegrated easily into respirable particles in air stream when emitted from the inhalation device were prepared by reducing the agitation speed after the dispersing medium was saturated with the bridging liquid. 相似文献
228.
Toshiharu Makino Hiromitsu Kato Sung-Gi Ri Satoshi Yamasaki Hideyo Okushi 《Diamond and Related Materials》2008,17(4-5):782-785
We have realized low specific on-resistance and ideal built-in potential simultaneously for a (111)-oriented homoepitaxial diamond p–n+ junction. As the p–n+ junction, the heavily phosphorus doped n+-type layer, which shows variable range hopping conduction, was formed on the (111)-oriented boron doped p-type one. By using this hopping conduction, the resistivity of the n+-type layer becomes lower by three orders of magnitude than that of a lightly P-doped layer. Current density–voltage characteristics showed a rectification ratio of 106 at ± 15 V at room temperature. The current density and the specific on-resistance at forward bias voltage of 15 V at room temperature are over 100 A/cm2 and 8 × 10− 2 Ωcm2, respectively. This low specific on-resistance corresponds to the lower resistivity of the n+-type layer by three orders of magnitude than that of conventional lightly P-doped n-type layer. The existence of the space-charge layer at the vicinity of the p–n+ junction was confirmed from capacitance–voltage (C–V) characteristics. From C−2–V characteristics at 200 °C, the built-in potential was estimated as approximately 4.4 eV, which is identical to that of conventional diamond p–n junction. 相似文献
229.
Nakamura Noriyuki; Fujita Kazuo; Ushitani Tomokazu; Miyata Hiromitsu 《Canadian Metallurgical Quarterly》2006,120(3):252
The authors compared perception of the standard and reversed Müller-Lyer figures between pigeons (Columbia livia) and humans (Homo sapiens). In Experiment 1, pigeons learned to classify 6 lengths of target lines into "long" and "short" categories by pecking 2 keys on the monitor, ignoring the 2 brackets so placed that they would not induce an illusion. In the test that followed, all 3 birds chose the "long" key more frequently for the standard Müller-Lyer figures with inward-pointing brackets (>). The subjects' responses were accountable by neither overall lengths of the figures nor horizontal gaps between the 2 brackets. For the reversed figures, effects of the brackets were absent. These results suggested that the pigeons perceived the standard Müller-Lyer illusion but not the reversed one. Experiment 2 confirmed that humans perceived both types of the illusion. Pigeons and humans may perceive the same illusory figures in different ways. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
230.
S. Tanaka A.A. Zakhidov R. Ovalle-Robles Y. Yoshida I. Hiromitsu Y. Fujita K. Yoshino 《Synthetic Metals》2009,159(21-22):2326-2328
We demonstrate a semitransparent organic photovoltaic (OPV) cell with two transparent electrodes: a multi-wall carbon nanotube (MWCNT) sheet and a Ga-doped ZnO (GZO) are used as a transparent anode and cathode, respectively. As an active layer, we used a bulk heterojunction structure with poly(3-hexylthiophene) (P3HT) and [6,6]-phenyl-C61 butyric acid methyl ester (PCBM). The photovoltaic cell has a GZO/P3HT:PCBM/poly(3,4-ethylene-dioxythiophene):poly(4-styrenesulfonate) (PEDOT:PSS)/MWCNT/PEDOT:PSS structure. For comparison, an OPV cell with a MWCNT-sheet anode and an indium tin oxide (ITO) cathode were also fabricated. The OPV cell with the GZO cathode showed better performance than that with the ITO cathode, owing to the lower work function of the former. The semitransparent OPV cell with GZO cathode demonstrated a short-circuit current of 3.4 mA/cm2, open-circuit voltage of 0.51 V, and efficiency of 0.45%. 相似文献