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41.
42.
It has been made clear through model simulations that dispersion-flattened and decreasing fiber (DFDF) is one of the most suitable fibers for broad-band supercontinuum (SC) generation. SC generation In a bandwidth of 280 nm with intensity fluctuation less than 15 dB has been experimentally observed by using the DFDF designed and manufactured with an optimized dispersion profile 相似文献
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44.
Forehead recontouring in endoscopic surgery is presented. Eleven cases of protruded forehead deformity caused by benign tumor and one case of concave deformity caused by depressed frontal bone fracture were treated. All lesions were approached through incisions made in the hair-bearing area and operated on endoscopically. This method left no scars on the forehead, and the results were satisfactory. It is considered to be an excellent procedure with regard to cosmetic results. 相似文献
45.
Y. Onishi N. Nishiyama C. Caneau F. Koyama Chung-en Zah 《Photonics Technology Letters, IEEE》2004,16(5):1236-1238
An all-optical inverter using transverse-mode switching of a 1.55-/spl mu/m vertical-cavity surface-emitting laser is demonstrated. When an external light is injected to a first high-order mode, the output power of the fundamental mode is strongly suppressed due to injection locking resulting in a large extinction ratio of over 20 dB. Waveform inversion is demonstrated for the input signal of a 5-GHz sinusoidal wave. 相似文献
46.
F Ohashi T Kotani T Onishi H Katamoto E Nakata B Fritz-Zieroth 《Canadian Metallurgical Quarterly》1993,55(5):875-876
Choroid plexus carcinoma was diagnosed in a 10-year-old maltese dog with chief complaint of progressive ataxia and head tilt. No abnormalities was observed on hemogram, radiographs of the skull, and electroencepharograph (EEG). Neurological examination suggested central vestibular lesions. On the magnetic resonance imaging (MRI) examination, images after contrast enhancement with Gadolinium DTPA-dimeglumine showed a rough circular lesion with an increased signal intensity in caudal fossa. This lesion was histopathologically confirmed to be choroid plexus carcinoma. 相似文献
47.
A ceramics acid, calcined at temperatures above 1000 °C, was obtained by impregnating aluminum hydroxide with aqueous ammonium
metatungstate followed by calcining in air at 1000–1200 °C (1–5 wt% W); its acidity and catalytic activity for decompositions
of toluene, ethylbenzene, and cumene are higher than those of silica-alumina. 相似文献
48.
49.
Taizo Hasegawa Takashi Betsui Shuichi Onishi Katsuaki Itoh Toyakazu Kohan Yoshihiro Makino Hiroshi Nakazawa 《Electrical Engineering in Japan》1992,112(1):84-92
Construction of 275-kV and 500-kV substations in densely populated areas is thought to be necessary in the future to maintain a stable supply of electricity. The use of gas-insulated transformers is now considered for substations because such transformers are non-flammable and nonexplosive. Since the completion of the 77-kV gas-insulated transformer in 1979, we have continued research to develop gas-insulated transformers applicable to a higher voltage level up to 500 kV. As the results of the research, 275-kV, 300-MVA a liquid cooling-type gas-insulated transformer has been developed. 相似文献
50.