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排序方式: 共有2275条查询结果,搜索用时 15 毫秒
921.
Tsuyoshi Ohgoh Toshiaki Fukunaga Toshiro Hayakawa 《Electrical Engineering in Japan》2007,158(1):53-59
We report high‐power technologies in 0.8‐µm Al‐free InGaAsP/InGaP laser diodes. To realize the high‐power operation, the improvement of catastrophic optical mirror damage (COMD) power density level is required. In addition to the use of low surface recombination velocity of Al‐free materials, optimization of waveguide thickness in broad waveguide structure with tensile‐strained barriers and current blocking structure near facets has led to high COMD power density level. Highly stable operation of Al‐free laser diodes with these structures has been obtained over 2500 hours at 2 W from a stripe width of µm. Applications of high‐power laser diodes are also described. © 2006 Wiley Periodicals, Inc. Electr Eng Jpn, 158(1): 53–59, 2007; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.20286 相似文献
922.
H Itabe H Yamamoto M Suzuki Y Kawai Y Nakagawa A Suzuki T Imanaka T Takano 《Canadian Metallurgical Quarterly》1996,271(52):33208-33217
Oxidatively modified low density lipoprotein (OxLDL) is known to be involved in atherogenesis. We have previously developed a murine monoclonal antibody, FOH1a/DLH3, which recognized oxidatively modified lipoproteins as well as foam cells in human atherosclerotic lesions (Itabe, H., Takeshima, E., Iwasaki, H., Kimura, J., Yoshida, Y., Imanaka, T., and Takano, T. (1994) J. Biol. Chem. 269, 15274-15279). The antigen of this monoclonal antibody was formed by peroxidation of phosphatidylcholine (PC), and the antigenic oxidized PC (OxPC) derivatives are thought to form complexes with polypeptides including apolipoproteins. OxLDL was measured by a sensitive sandwich enzyme-linked immunosorbent assay using the monoclonal antibody and anti-human apolipoprotein B antibody, in which antigenic OxPC competed with OxLDL. When antigenic activities of PC analogs were tested by the competition assay, 1-palmitoyl-2-(9-oxononanoyl) PC (9-CHO PC) and the hydroperoxide of egg PC potently inhibited the detection of OxLDL. 1-Palmitoyl-2-linoleoyl PC was oxidized with ferrous ion and ascorbic acid, and the antigenic products were purified from the OxPC extracts on high pressure liquid chromatography columns and subsequently analyzed by laser desorption mass spectrometry. Molecular weight determination and retention times of high pressure liquid chromatography suggest that one of these products was 9-CHO PC. Other products are thought to be 8-carbon aldehyde, dihydroxy, and ketohydroxy derivatives of PC. When a C-terminal 16-mer synthetic peptide of the 70-kDa peroxisomal membrane protein was simply incubated with 9-CHO PC, it was found to be reactive in a sandwich enzyme-linked immunosorbent assay using FOH1a/DLH3 and an anti-peptide antiserum. These results suggest that the anti-OxLDL monoclonal antibody FOH1a/DLH3 reacts with several oxidized products of PC including aldehyde derivatives of PC, which covalently modify polypeptides. 相似文献
923.
K. Kida M. Nakagawa H. Nishisako S. Morimura 《Journal of the Institute of Brewing》1998,104(5):265-272
During commercial scale fermentation for the production of rice shochu using post-distillation slurry in place of the first-stage mash, it was difficult to stir the mash from the first to the third day because of the high viscosity of the mash. Shochu was therefore fermented with a two-step addition of cooked rice, adding rice on the first and third days, to reduce the viscosity of mash during the first few days. Even though the ethanol concentration of the mash after 9 d was 17.2 v/v% and was a little lower than that obtained in laboratory scale tests, the yield of pure ethanol was 473 ml kg?1 of rice and this value was higher than the average value (450 ml kg?1) when shochu is made in the standard manner on a commercial scale. The shochu produced on a commercial scale by the newly developed recycling process was very mild and smooth, and received high scores in sensory tests. 相似文献
924.
Nakagawa Y. Mimura M. Miyano K. Koyanagi Y. Fujimoto K. 《Vehicular Technology, IEEE Transactions on》2003,52(5):1189-1195
The paper presents an improved method for evaluating antenna performance in a multipath propagation environment. It demonstrates, theoretically and experimentally, that by using polarization and phase terms of the incident field and the antenna system in the evaluation of the antenna effective gain (AEG), the AEG can be evaluated more efficiently as compared with the conventional method. First, a theoretical expression of the received power is given by using the open-circuit voltage at the antenna terminals, in which both the polarization and the phase of the incident field and antenna gain patterns are explicitly used. Secondly, a newly developed system for the measurement of field parameters, such as polarization and phase as well as amplitude, is introduced. Thirdly, incident field parameters measured in urban and suburban areas of Tokyo are described. It was confirmed that major incident waves were counted in up to five or six directions at a mobile terminal and their polarizations and phases were different depending on the direction of incidence. Also, measurement of the antenna gain patterns of the latest personal digital cellular handset at a talk position finds the dependence of the AEG on polarization and phase, which were significantly varied by the body effect. Finally, the AEG is evaluated based on the method introduced here, and its usefulness is compared with that of the conventional method. 相似文献
925.
Kazuaki Arai Hiroshi Tateishi Ko Agatsuma Takashi Saito Nobuyuki Sadakata Mikio Nakagawa 《Electrical Engineering in Japan》1995,115(4):1-13
A new type of superconductor is being developed for the application of high-field pulsed superconducting magnets, which are called fiber-reinforced-superconductors (FRS). A filament of FRS consists of a reinforcement fiber with high elastic modulus and a superconducting layer around it. The strain can be reduced against electromagnetic force because of highelastic modulus fibers. If Nb3Sn target is utilized, the preparation process of FRSs is shortened and there is the possibility to produce Nb3Sn layer which leads to high current density because of its uniform stoichiometric Nb3Sn layer. This paper presents first a technique of preparing a single-phase target of Nb3Sn to produce superconducting layers on reinforcement fibers of FRSs. Mixture of niobium and tin powder was reacted in a furnace filled with argon gas to be Nb3Sn, and then it was broken and cast into a stoichiometric target with a diameter of 77 mm. The critical temperature of the target itself was 17.5 K. The thin film deposited with the target showed no superconductivity without post annealing, but it had critical temperature from 14.5 K to 12.5 K after heat treatment. Second, a new target containing rich tin was prepared and the film deposited with it had superconductivity without post annealing. 相似文献
926.
Toshiaki Murai 《Electrical Engineering in Japan》1995,115(4):134-145
In commercializing the superconducting maglev system, it is important to reduce the cost, especially that of ground coils installed all along the guideway. The ground coils designed for Yamanashi test track under construction are composed of both octagonal-shaped null-flux coils for EDS (Electrodynamic Suspension) and double-layered armature coils of LSM (Linear Synchronous Motor). The former reduces the magnetic drag of the running resistance, and the latter reduces the electromagnetic fluctuation in the superconducting coils. In addition, the octagonal-shaped coils can generate propulsion force by being connected to the power supply. This system can generate levitation force, guidance force and propulsion force by the same ground coils. Therefore this system is expected to reduce the cost of ground coils, the number of which is decreased. This paper presents the principle and analytical formula of the combined propulsion, levitation and guidance system (PLG system), including one for angles. In addition, using numerical examples, the characteristics of this system are expressed. 相似文献
927.
This paper shows that the problem of designing one-dimensional (1-D) variable fractional-delay (VFD) digital filter can be elegantly reduced to the easier subproblems that involve one-dimensional (1-D) constant filter (subfilter) designs and 1-D polynomial approximations. By utilizing the singular value decomposition (SVD) of the variable design specification, we prove that both 1-D constant filters and 1-D polynomials possess either symmetry or anti-symmetry simultaneously. Therefore, a VFD filter can be efficiently obtained by designing 1-D constant filters with symmetrical or antisymmetrical coefficients and performing 1-D symmetrical or antisymmetrical approximations. To perform the weighted-least-squares (WLS) VFD filter design, a new WLS-SVD method is also developed. Moreover, an objective criterion is proposed for selecting appropriate subfilter orders and polynomial degrees. Our computer simulations have shown that the SVD-based design and WLS-SVD design can achieve much higher design accuracy with significantly reduced filter, complexity than the existing WLS design method. Another important part of the paper proposes two new structures for efficiently implementing the resulting VFD filter, which require less computational complexity than the so-called Farrow structure. 相似文献
928.
Yoshiki Nakagawa Hiroyuki Satoh Toshifumi Nakamura Kenji Okajima Sueharu Maenosono Osamu Tokuhiro 《Journal of the Society for Information Display》2004,12(4):435-440
Abstract— A novel liquid‐crystal alignment method, diamond‐like carbon and ion beam alignment (DLC/IB) technology, was announced at the 2001 SID Symposium. And since December 2001, a new‐generation ion‐beam machine has been placed into the manufacturing line of IDTech. DLC/IB technology is mainly used for medical displays, which require a monochrome high‐density and super‐uniform display. We report on the latest developments of these advanced monochrome displays. 相似文献
929.
With some models of computerized scanners, it is possible to obtain not only axial, but also coronal tomograms. This is feasible because a water bag is not used and limited tilting capacity is built into the gantry. The head is extended and the central ray directed perpendicularly to the base of the skull. The resulting views, orthogonal to the conventional axial views, furnish important complementary information. 相似文献
930.
A drum friction test was conducted on four different ‘flame-resistant’ and one ‘non-flame-resistant’ rubber conveyor belts with a fabric skeleton manufactured in Japan. These test results were compared with those obtained from the other flammability tests, i.e. a small-scale flame test, an oxygen index test and a laboratory-scale gallery test, and both sample and rank correlation coefficients were calculated. As a result, the authors have concluded that fire resistance of belting materials themselves could not be adequately assessed by the results from the drum friction test, which could have some significance only when other combustible materials exist near the drive pulleys or idlers of belt conveyors. 相似文献