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排序方式: 共有891条查询结果,搜索用时 15 毫秒
71.
Kazuhiro Kanda Noriko Yamada Kumiko Yokota Masahito Tagawa Masahito Niibe Makoto Okada Yuichi Haruyama Shinji Matsui 《Diamond and Related Materials》2011,20(5-6):703-706
Surface modification of diamond-like carbon (DLC) film was performed using a hyperthermal atomic fluorine beam on the purpose of production of hydrophobic surface by maintaining the high hardness of DLC film. By the irradiation of atomic fluorine beam of a 1.0 × 1020 atoms/cm2, the contact angle of a water drop against the DLC surface increased from 73° to 111°. The formation of CF3, CF2 and CF bonding on the modified DLC surface was confirmed from the measurements of X-ray photoelectron spectra and near-edge X-ray absorption fine structure spectra. Irradiation of hyperthermal atomic fluorine beam was concluded to produce insulator fluorine-terminated DLC film, which has high F content on the surface, by the taking of the use of neutral atomic beam as a fluorine source. 相似文献
72.
73.
Riho Kataishi Takayuki Ikeda Toshiki Sasaki Kouhei Toyotaka Daiki Nakamura Hiroyuki Miyake Yuji Iwaki Kazunori Watanabe Yuichi Yanagisawa Hisao Ikeda Harue Nakashima Nobuharu Ohsawa Shingo Eguchi Satoshi Seo Yoshiharu Hirakata Shunpei Yamazaki Daisuke Kurosaki Masakatsu Ohno Chris Bower Darryl Cotton Andrew Matthews Piers Andrew Catalin Gheorghiu Johan Bergquist 《Journal of the Society for Information Display》2014,22(8):381-392
In this study, white organic electroluminescent devices with microcavity structures were developed. A flexible high‐resolution active‐matrix organic light‐emitting diode display with low power consumption using red, green, blue, and white sub‐pixels formed by a color‐filter method was fabricated. In addition, a side‐roll touch display was developed in combination with a capacitive flexible touch screen. 相似文献
74.
Saki Kondo Tsukasa Azeta Yoshiaki Ukita Yuichi Utsumi 《Microsystem Technologies》2010,16(8-9):1577-1580
The use of three-dimensional (3D) microstructures is becoming essential attempt to develop next generations’ microdevices, to integrate many modules and various functions, and enhance the performance of device. In this paper, we present a new concept for lab on a chip using 3D structure and centrifugal pumping for integrated functional fluid systems such as high-throughput screening, and point of care testing systems which has stacked multiple structures with 3D-interconnection. The use of 3D structure brings many benefits for above high throughput systems, such as possibility to integrate various modules enabling to perform total assay operation, from sample preparation for biochemical reaction and their detection on one platform. For this concept, the most important key technology is control of a vertical valving and transportation of liquid between different 2D micro channel networks with different height levels. We demonstrated such vertical liquid transportation in 3D micro channel networks through the high aspect ratio capillary bundle filter by controlling spinning speed of device and centrifugal force as a pumping force, and confirmed capillary bundle could be employed as vertical microvalve for 3D fluidic systems using centrifugal force as a pumping method. 相似文献
75.
Ali Dashti Ahmad Ramazani SA Yuichi Hiraoka Sang Yull Kim Toshiaki Taniike Minoru Terano 《Polymer International》2009,58(1):40-45
BACKGROUND: Kinetic and morphological aspects of slurry propylene polymerization using a MgCl2‐supported Ziegler–Natta catalyst synthesized from a Mg(OEt)2 precursor are investigated in comparison with a ball‐milled Ziegler–Natta catalyst. RESULTS: The two types of catalyst show completely different polymerization profiles: mild activation and long‐standing activity with good replication of the catalyst particles for the Mg(OEt)2‐based catalyst, and rapid activation and deactivation with severe fragmentation of the catalyst particles for the ball‐milled catalyst. The observed differences are discussed in relation to spatial distribution of TiCl4 on the outermost part and inside of the catalyst particles. CONCLUSION: The Mg(OEt)2‐based Ziegler–Natta catalyst is believed to show highly stable polymerization activity and good replication because of the uniform titanium distribution all over the catalyst particles. Copyright © 2008 Society of Chemical Industry 相似文献
76.
Yuichi Tamura 《Corrosion Science》2009,51(7):1560-223
Effect of surface oxide on Pt-Co alloy electrodes on the oxygen reduction reaction (ORR) was investigated in 0.5 M sulfuric acid solution by electrochemistry, ellipsometry, laser Raman scattering spectroscopy, and XPS. The oxide as thick as 1-2 nm increases the overpotential of ORR and falls down efficiency of PEFC. The thickness of the oxide films is precisely determined by ellipsometry. The oxide film 1.9 nm thick was formed on Pt-50 mol% Co electrode by constant potential oxidation at 1.20 V and the film 1.5 nm thick remains on the electrode at 0.6 V at which ORR already starts. The remaining oxide decreases the current density of ORR and increases the overpotential. On pure Pt electrode, the similar influence of the oxide film was observed. 相似文献
77.
Tetsukuni Oikawa Masaaki Kondo Yoshinobu Mizuno Yuichi Watanabe Hiroshi Fukuoka Ken Muramatsu 《Reliability Engineering & System Safety》1998,62(3):251-271
An integrated code system SECOM-2, developed at the Japan Atomic Energy Research Institute (JAERI), has the following functions for systems reliability analysis in seismic probabilistic safety assessments (PSAs): (1) calculation of component failure probability, (2) extraction of minimal cut sets (MCSs) from a given fault tree (FT), (3) calculation of frequencies of accident sequences and core damage, (4) importance analysis with several measures with consideration of unique parameters of seismic PSAs, (5) sensitivity analysis, and (6) uncertainty analysis. This paper summarizes the special features of SECOM-2 to perform the analyses mentioned above. At JAERI, using an integrated FT which represents seismically induced core damage due to all initiating events as a system model to calculate core damage frequency of a nuclear power plant, SECOM-2 can calculate conditional point estimate probabilities of system failures, losses of safety functions, and core damage as a function of earthquake motions. The point estimate is computed by a method which gives an exact numerical solution using the Boolean arithmetic model method. As for consideration of correlation of component failure, which has been an important issue in seismic PSAs, a new technique based on direct FT quantification by a Monte Carlo simulation is being added to SECOM-2. Adding this technique, the core damage frequency can be calculated not only with the upper bound approximation based on MCSs but also with a near exact solution taking into account the correlation among all components. This paper also presents the preliminary results of a seismic PSA of a generic BWR plant in Japan performed at JAERI to demonstrate the functions of the SECOM-2 code. 相似文献
78.
Based on the present state of the art of the separation technology, recycling of fission-product rare elements (FRE) in the FBR spent fuel is discussed. The rad.-waste fractionation is in accordance with the present society's trend toward zero-emission, and the mean of salt-free method utilizing electrochemistry agrees with the principles of the newly established green chemistry. A catalytic electrolytic extraction method is proposed to separate the target, radioactive but potentially strategic elements, Pd, Ru, Rh, Re (Tc), Te and Se dissolved in the HLLW. It avoids secondary waste arising. This method is particularly feasible for the separation of Pd where cyclic reaction of metal cations such as Pd(II) or Fe(II), acting as promoters or mediators and already contained in HLLW, accelerates the electrochemical deposition of Ru, Rh and Re. Elemental separation not only offers alternative material resources to meet expanding demands for catalysts in Fuel Cell/Soft Energy system but is also the first step for transmutation or other selective strategies for waste management of long-lived fission products (LLFP). 相似文献
79.
Tadao Tanabe Yuichi Kozawa Ken Suto Jun-ichi Nishizawa Ytaka Oyama 《Journal of Infrared, Millimeter and Terahertz Waves》2005,26(6):881-892
Stimulated Raman gain (SRG) spectroscopy using infrared pump pulses with narrow linewidth and a low-noise cw probe infrared laser was proposed. High-resolution Raman spectra of solutions were obtained. The SRG spectra of crystal GaP, benzene, and toluene were measured to confirm the spectral resolution and sensitivity over the terahertz (THz) region. We discuss the polarization dependence of the spectral measurement of carbon tetrachloride. Our system can detect organic molecules in aqueous solutions. 相似文献
80.
The hot plate ignition test was conducted on ten different conveyor rubber belts with fabric skeletons. In this test, a 25 × 25 mm2 belt sample was placed on a stainless steel plate in an electric furnace and heated. The ‘ignition temperature’ was determined on each sample in almost the same way as proposed in Canada. The test results were compared with those from other laboratory-scale flammability tests (i.e. the small-scale flame tests, the Oxygen Index test and the laboratory-scale gallery test). The calculated results of both sample and rank correlation coefficients imply that the ‘10 signition temperature’ in this hot plate ignition test has a correlation with the results from both the Oxygen Index test and the laboratory-scale gallery test, but that it has very little or no correlation with those from the small-scale flame tests. On the other hand, it is found that the ‘60 s ignition temperature’ in this test has a far better correlation both with the results from the small-scale flame tests and with the time to ignition in the laboratory-scale gallery test than the ‘10 s ignition temperature’. 相似文献