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排序方式: 共有697条查询结果,搜索用时 209 毫秒
1.
2.
Ichiro Hirosawa Tetsuo Honma Kazuo Kato Naoto Kijima Yasuo Shimomura 《Journal of the Society for Information Display》2004,12(3):269-273
Abstract— We studied the influence of annealing in air on doped europium in BaMgAl10O17 by performing x‐ray absorption fine‐structure measurements. We determined the oxidation of doped divalent europium by annealing in air at over 500°C. The interatomic distance between the europium and the surrounding oxygen atoms was compressed by oxidation. It also appears that the oxidation process of europium is determined by the diffusion of oxygen into BaMgAl10O17. 相似文献
3.
Photoinduced Formation of Small Gold Particles in Silica Gels 总被引:2,自引:0,他引:2
AuCl− 4 ions in sol-gel-derived silica gels (Au/silica gels) were photoreduced by ultraviolet light irradiation at room temperature. In the presence of ethylene glycol in the silica gels, small Au particles were effectively formed by the irradiation. When the storage temperature of the gels was increased in the dark after the irradiation, the surface plas-mon resonance absorption peak of the Au particles was shifted to longer wavelengths, indicating that the Au particles became large. At a storage temperature below 9°C, Au particles could not be observed in the silica gels. The apparent activation energy of Au particle formation was estimated to be 17. 3 kcal·tmol−1 . 相似文献
4.
This paper presents an application of digital signal processing to data acquired by the radio imaging method (RIM) that was adopted to measure moisture distribution inside the human body. RIM was originally developed for the mining industry; we are applying the method to a biomedical measurement because of its simplicity, economy, and safety. When a two‐dimensional image was constructed from the measured data, the method provided insufficient resolution because the wavelength of the measurement medium, a weak electromagnetic wave in a VHF band, was longer than human tissues. We built and measured a phantom, a model simulating the human body, consisting of two water tanks representing large internal organs. A digital equalizer was applied to the measured values as a weight function, and images were reconstructed that corresponded to the original shape of the two water tanks. As a result, a two‐dimensional image containing two individual peaks corresponding to the original two small water tanks was constructed. The result suggests the method was applicable to biomedical measurement by the assistance of digital signal processing. This technique may be applicable to home‐based medical care and other situations in which safety, simplicity, and economy are important. 相似文献
5.
Micrometer‐sized, monodisperse, magnetic composite particles were prepared by heating micrometer‐sized, monodisperse, hollow polystyrene/polydivinylbenzene composite polymer particles at 200°C for 4 h (particles had been dipped in pentacarbonyliron) and then washed in 12 N HCl and water. The hollow polymer particles were produced by seeded polymerization by the dynamic swelling method that was proposed by authors. The magnetic composite particles contained Fe3O4, the content of which was 49% based on total weight, and were attracted easily in water by a 1650 G magnet. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 88: 428–433, 2003 相似文献
6.
7.
Y. Nakamura Ichiro Tanaka N. Takeuchi S. Koshiba H. Sakaki 《Journal of Electronic Materials》1998,27(11):1240-1243
We studied morphology of GaAs surfaces and the transport properties of two-dimensional electron gas (2DEG) on vicinal (111)B
planes. Multi-atomic steps (MASs) are found on the vicinal (111)B facet grown by molecular beam epitaxy, which will affect
electron transport on the facet. We also studied how the morphology of GaAs epilayers on vicinal (111)B substrates depends
on growth conditions, especially on the As4 flux. The uniformity of MASs on the substrates have been improved and smooth surfaces were obtained when the GaAs was grown
with high As4 flux, providing step periodicity of 20 nm. The channel resistance of the 2DEG perpendicular to the MASs is reduced drastically
with this smooth morphology. These findings are valuable not only for fabricating quantum devices on the (111)B facets but
also those on the vicinal (111)B substrates. 相似文献
8.
Kiyoaki Imoto Kohshin Takahashi Takahiro Yamaguchi Teruhisa Komura Jun-ichi Nakamura Kazuhiko Murata 《Solar Energy Materials & Solar Cells》2003,79(4):459-469
Here, we reported that a new carbon electrode prepared with an activated carbon was superior to a Pt sputtered electrode as the counter electrode of dye-sensitized solar cells. The photovoltaic performance was largely influenced by the roughness factor of carbon electrode. The open-circuit voltage increased by about 60 mV using the carbon counter electrode compared to the Pt counter electrode because of positive shift of the formal potential for I3−/I− couple. 相似文献
9.
10.
T Kuroda M Saeki K Tanaka M Komura T Honna M Nakano M Sugiyama S Nakagawa K Miyasaka 《Canadian Metallurgical Quarterly》1998,33(11):1641-1644
BACKGROUND/PURPOSE: To develop practical and less invasive techniques for fetal endoscopic surgery, new methods of lifting the uterine wall to allow fetal surgery without maternal laparotomy were developed and assessed. METHODS: Fetal endoscopic surgical procedures, including tracheostomy and umbilical vascular cannulation, were performed using one of the three methods to enter the uterus without maternal laparotomy in pregnant goats (n = 6; 105 to 115 days' gestation): (1) direct uterine lifting with an air-cushion device; (2) indirect uterine lifting, in which the uterine wall was fixed to the maternal abdominal wall using balloon tip ports inserted percutaneously by Seldinger's method, then the maternal abdomen was lifted mechanically; and (3) combined method, in which low pressure CO2 (5 mm Hg for initial inflation and 2 mm Hg for maintenance) was insufflated into the uterus in addition to the indirect uterine lifting cited above. RESULTS: The direct uterine lifting caused massive injury of myometrium and uterine membranes. The creation of intrauterine space and the protection of the membranes were not accomplished effectively by the indirect uterine lifting only. The combined method provided the adequate intrauterine space and excellent endoscopic visibility for completion of the endoscopic procedures with minimal uterine injury. CONCLUSION: The fetal endoscopic surgery may be accomplished simply and safely by the combined method, a novel technique of uterine lifting to allow fetal surgery without maternal laparotomy. 相似文献