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51.
Analysis and experiment of a new leaky nrd guide based on a grating structure is described. Analysis employs a mode coupling procedure which yields highly accurate results while presenting the advantage of simplicity and ease of manipulation. Numerical values for the phase and leakage constants are presented and the role of each grating parameter is assessed. Theoretical results are compared with experimental data for different geometric and constitutive parameters and reasonable agreement between them is obtained. 相似文献
52.
53.
Otsuji T. Yoneyama M. Murata K. Imai Y. Enoki T. Umeda Y. 《Electronics letters》1997,33(16):1376-1377
The authors report a 2-46.5 GHz quasi-static frequency divider IC using InAlAs/InGaAs/InP HEMTs. Wideband clock/data buffers and an HLO (high-speed latching operation)-type T-FF were incorporated to enhance the operating range. The IC was mounted on a dedicated IC package and operated up to 45.2 GHz 相似文献
54.
Ultrasonic bone densities were measured in 131 lactating women, aged 21 to 42 years, at 6-590 days postpartum. STIFFNESS Calculated from the combined value of speed of sound and broadband ultrasound attenuation at the calcaneus was used as an index of bone density. The relationships of STIFFNESS with period of lactation, current and past consumption of cow's milk, various food intake frequency, history of participating in sports, daily physical activity, using calcium drugs and sun exposure were examined using stepwise multiple regression analysis, including age and weight as independent variables. 1) The mean (SD) of STIFFNESS was 79.8 (11.9). Thirty-three women (25% of subjects) showed STIFFNESS less than 70. 2) Period of lactation showed a significant negative effect on STIFFNESS (p < 0.05). However, no such effect appeared for women with cow's milk intake of less than 100 ml per day. This result suggests a protection of calcium levels in bone. 3) Current daily cow's milk intake showed significant positive effect on STIFFNESS (p < 0.05). For women lactating less than 150 days, this relation between cow's milk intake and STIFFNESS was clear (r = 0.44, p < 0.01). 4) Significant relation between STIFFNESS and food intake frequencies was found in milk and milk products only among various foods. This result indicates that cow's milk and milk products are important sources of calcium during lactation. 相似文献
55.
Kazuhiro Saito Mitsuru Yoneyama Mitsuyoshi Saito Keiichi Ikegami Michio Sugi
Takayoshi Nakamura
Mutsuyoshi Matsumoto Yasujiro Kawabata 《Thin solid films》1988,160(1-2):133-137Photoelectric cells based on Langmuir-Blodgett (LB) films were fabricated using dye monolayers as photoconductors and N-docosylpyridinium-di(tetracyanoquinodimethane) (PT) monolayers as one of the electrode materials. It is found that PT films can be used as a wiring material instead of large work function metals such as silver or Ni-Cr. However, in comparison with the photoelectric cells using the conventional metals, a few different properties were observed for those wired with PT. These differences are assignable to the difference between the LB film-metal and the LB film-LB film contacts. 相似文献
56.
57.
H. Mori H. Miyoshi K. Takeda H. Yoneyama H. Fujita Y. Iwata Y. Otsuka Y. Murata 《Journal of Materials Science》1992,27(12):3197-3199
The microstructures of iron oxide-pillared montmorillonite have been investigated by highresolution transmission electron microscopy. The iron oxide is incorporated in the interlayer space of montmorillonite as Fe2O3 crystallites. The crystallites are present in two different morphologies: isolated particles 10 nm long and 4 nm thick, and bands (possibly plates) with a thickness 1 nm running parallel to the basal plane. 相似文献
58.
In order to improve the mechanical properties of polypropylene film, a new processing combining extrusion and zone-annealing has been applied. It was found that there are suitable conditions for each step in the combined processing. When the coextrusion draw ratio was low, the total draw ratio and modulus could be increased by the zone-annealing subsequently done. The highest modulus was obtained when the film was coextruded at extrusion draw ratio 4 and then zone-annealed at 120°C under 7 kg/mm2. The value was 12 GPa in Young's modulus or 17 GPa in dynamic modulus. The peak temperature of αc dynamic dispersion for the combinedly processed film was 109°C, which is higher by 10°C than that for the as-coextruded film. Four drawing methods were compared in dynamic viscoelasticity. These methods are the coextrusion, zone-drawing/zone-annealing, two-step coextrusion, and the combined processing by coextrusion and zone-annealing. The highest dynamic modulus for each method was arranged in the above order. The combined processing indicated the most effective improvement in mechanical properties, because it is believed that lamellae in the original film were broken by cooperating interaction of shear stress, compression, and tension on coextrusion and then the superstructure with a high crystallinity and a high molecular orientation was formed on zone-annealing. 相似文献
59.
A photo-electrochemical cell was demonstrated which had a TiO2 electrode as an anode, p-GaP as a cathode, and 1 N H2SO4 of 1 N NaOH as an electrolyte. The cell reaction was the decomposition of water, ie, oxygen evolution at the anode and hydrogen evolution at the cathode. The open current voltage was 0·58 V for the acid electrolyte and 0·4 V for the base. Deterioration of the cell performance was observed, and this was mainly due to the p-GaP electrode. The deterioration was possibly brought about by a change of surface condition of the p-GaP electrode with working time. Utilization of solar energy was found to be quite limited by the pair of semiconductors chosen. 相似文献
60.
Teruhisa Satsuki Kenji Umehara Yuji Yoneyama 《Journal of the American Oil Chemists' Society》1992,69(7):672-677
The detergency properties of α-sulfonated fatty acid methyl esters (α-SFMe) were evaluated and compared to those of conventional
anionic surfactants by using a model heavy-duty detergent formulation. Several physicochemical properties of surfactants were
measured to investigate the effective factors on detergency. α-SFMe showed good detergency performance under various washing
conditions. These results were considered to correlate well with the good adsorption behavior on oils and dispersing capabilities
for particles, as well as with the good solubilization capacity. Solubilization behavior of α-SFMe is discussed in relation
to micelle properties. It is suggested that α-SFMe can form suitable micelles for solubilizing polar oils advantageously,
due to its bulky hydrophilic group. 相似文献