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91.
The scattering and mode conversion of guided modes caused by a cylindrical scatterer of arbitrary cross section embedded in, or placed on, a dielectric slab waveguide are investigated theoretically. The method employed for the analysis is the surface current integral equation technique. The total scattered power, mode-conversion coefficients, and scattering patterns for the typical numerical examples are shown. 相似文献
92.
Electron microscopic in situ hybridization (EM-ISH) is a useful method in determining the localization of a specific nucleic acid at the ultrastructural level. Since the EM-ISH protocol includes many steps, no standard protocol for EM-ISH is available yet. In this study, we optimized quantitatively the critical conditions with respect to embedding resin, nucleic acid labeling and hybridization reaction time, by using adenovirus-infected cells as the indicator cells. The optimal detection of an adenovirus-specific nucleic acid was obtained by overnight hybridization reaction on sections embedded in Lowicryl K4M resin. Random-primed-labeled probes improved the reactivity. At least 60% of virus particles in paracrystalline arrays was found to contain viral DNA. These arrays in adenovirus-infected cells are useful in evaluating quantitatively the efficiency of protocols of EM-ISH. 相似文献
93.
A. Idesaki M. Narisawa K. Okamura M. Sugimoto Y. Morita T. Seguchi M. Itoh 《Journal of Materials Science》2001,36(2):357-362
A fine SiC fiber is synthesized from a polymer blend of polycarbosilane (PCS) and polyvinylsilane (PVS) with electron beam curing under vacuum. The obtained SiC fiber from the PCS-PVS blend polymer has smaller average diameter of 8.5 m than that of 11.8 m from PCS, and shows higher average tensile strength of 3.2 GPa than that of 2.8 GPa from PCS after heat treatment at 1673 K in Ar gas atmosphere. However, the SiC fiber from the polymer blend decreases in tensile strength after heat treatment above 1773 K due to -SiC crystal growth near the fiber surface, because of a small amount of oxygen incorporated in the fiber. 相似文献
94.
K. Matsuda Y. Yamaguchi N. Morita T. Matsunobe M. Yoshikawa 《Thin solid films》2007,515(17):6682-6685
We have measured Raman and Electron-spin resonance (ESR) spectra of fluorine-doped SiO2 films deposited by two different methods. In high-density plasma (HDP) films, the Raman band at about 490 cm− 1 becomes drastically stronger as the F/Si ratio increases, whereas the Raman band from threefold ring defect is independent of the F/Si ratio. The unusual increase of the intensity of the 490 cm− 1 band in HDP films has been interpreted in terms of the existence of Si-Si clusters. From a comparison between Raman spectra of HDP film and plasma chemical vapor deposition using tetraethoxysilane (p-TEOS) film with the same F/Si ratios it has been found that HDP film has more Si-Si bonds and threefold ring defects than p-TEOS film. Furthermore, the polarized Raman spectra in the 810 cm− 1 bands indicate that inhomogeneous SiO2 clusters of various sizes should exist in the network structure of HDP film. The result of the ESR measurement shows that HDP films have fewer dangling bonds than p-TEOS films. It is considered that many Si-Si clusters, threefold ring defects, and inhomogeneous SiO2 cluster sizes, and the few dangling bonds in HDP films give rise to the film properties of low stress, good adhesion with Si substrate, and low water permeation. 相似文献
95.
Thermal Degradation Under Pulse Operation in Low-Temperature p-Channel Poly-Si Thin-Film Transistors
Shinichiro Hashimoto Koji Kitajima Yukiharu Uraoka Takashi Fuyuki Yukihiro Morita 《Electron Devices, IEEE Transactions on》2007,54(2):297-300
We analyzed the heat generation of a low-temperature polycrystalline thin-film transistor in pulse operation and proposed a technique for accurately measuring its thermal temperature in high-frequency operation. From this measurement, we were able to calculate the time constants for heating and radiation for the first time. At a low frequency, the temperature difference between when the pulse was on and off was remarkable. As the frequency was increased, the maximum and minimum temperatures approached each other and became equal at a frequency of approximately 1 kHz. We also measured the degradation in pulse operation and discussed the relationship between the thermal temperature and the degradation in the pulse operation 相似文献
96.
Daikoku M. Morita I. Taga H. Tanaka H. Kawanishi T. Sakamoto T. Miyazaki T. Fujita T. 《Lightwave Technology, Journal of》2007,25(1):139-145
In order to realize a future 100-Gb Ethernet (100 GbE) transport, 100-Gb/s transmission without 100-GHz-class electronics and optical time-division-multiplexing technique was demonstrated. By using a differential quadrature phase-shift-keying (DQPSK) modulation format and commercially available electronics, 2- and 50-km transmissions of 100-Gb/s signal were successfully achieved over a standard single mode fiber. The receiver sensitivity, chromatic dispersion, and differential group delay tolerances of 100-Gb/s DQPSK signal were also evaluated. Through these evaluations, the possibility of DQPSK modulation for future 100-GbE transport is verified 相似文献
97.
We have developed the separated pulsed laser deposition (SPLD) technique to prepare high quality ZnO based films exhibiting uniform and droplet-free properties. This SPLD consists of an ablation chamber and a deposition chamber which can be independently evacuated under different ambient gases.The gas species and the pressures in both chambers can be arbitrarily chosen for the specific deposition such as nanostructured films and nanoparticles. The ablation chamber is a stainless steel globe and the deposition chamber is a quartz tube connected to a metallic conic wall with an orifice. We used a KrF excimer laser with λ = 248 nm and 25 ns pulse duration. The different gas conditions in two chambers allow us to realize optimal control of the plasma plume, the gas phase reaction and the film growth by applying the bias voltage between the conic wall and the substrate under the magnetic field. We can expect that at appropriate pressures the electric and magnetic field motion (E × B azimuthal drift velocity) gives significant influences on film growth.We have deposited ZnO thin films at various pressures of ablation chamber (Pab) and deposition chamber (Pd). The deposition conditions used here were laser fluence of 3 J/cm2, laser shot number of 30,000, Pab of 0.67-2.67 Pa (O2 or Ar), Pd of 0.399-2.67 Pa (O2), and substrate temperature of 400 °C. Particle-free and uniform ZnO films were obtained at Pab of 0.67 Pa (Ar) and Pd of 1.33 Pa (O2). The ZnO film showed high preferential orientation of (002) plane, optical band gap of 2.7 eV, grain size of 42 nm and surface roughness of 1.2 nm. 相似文献
98.
Methacrylic acid (MAA) and methyl methacrylate (MMA) were grafted onto nylon 6, cellulose triacetate, cotton, viscose rayon, and polyester fibers, and the stereoregularities of the grafted polymers were determined. The graft polymerization was carried out with preirradiation techniques using γ-rays from a Co 60 source. The grafted copolymers were then separated from the homopolymers by Soxhlet extraction. The grafted (branch) polymers were isolated from the trunk polymers by acid hydrolysis and their stereoregularity was determined with a 100 MHz NMR spectrometer. The stereo-regularity of PMAA or PMMA grafted onto viscose rayon or cotton fiber was different from that of the polymers formed in ordinary radical polymerization. 相似文献
99.
Kanichi Kamiya Tomoaki Nishijima Katsuhisa Tanaka 《Journal of the American Ceramic Society》1990,73(9):2750-2752
Dip-coated sol–gel-derived TiO2 films on an alumina substrate were converted to nonstoichiometric titanium nitride (TiN x ( x ≦ 1)) films by heating at approxmately 1000°C in NH3 gas. TiO2 films made from TiO2 sols prepared from Ti(O– i -C3 H7 )4 and stabilized by diethanolamine were more easily nitrided than those from sols containing HCl as a deflocculant reagent. This appears to be a result of the more porous structure of the former films. 相似文献
100.
Yoshihiro Hishikawa Haitao Liu Hsin‐Hsin Hsieh Takamitsu Inoue Kyung‐Soo Kim Chamnan Limsakul Seong‐Won Kim Ruengrit Ninae Kengo Morita 《Progress in Photovoltaics: Research and Applications》2013,21(5):1181-1188
Because of recent advances in the production and installation of photovoltaic (PV) systems, the international conformity of PV module performance measurement has become increasingly important. The increase in PV production sites is particularly significant in the Asian region. The present paper summarizes and discusses the results of a round‐robin intercomparison of crystalline silicon modules among national laboratories and certified testing laboratories in the Asian region conducted from 2009 to 2011. Most of the values of Pmax measured at the different laboratories were within a ±2% range, although some Pmax results showed differences of up to about 3%. This result is comparable to that obtained in the recent intercomparison among international laboratories. Possible sources of difference in the measured values of Isc, Voc, FF, and Pmax are discussed, for further improvement of international conformity in PV measurement technologies. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献