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Electrical properties of phosphorus-implanted silicon annealed by a single shot of a high-power pulsed electron beam have been studied by differential Hall-effect and sheet-resistivity measurements. Nearly 100% electrical activation of implanted phosphorus can be obtained after electron-beam annealing at an incident energy density of 0.92 J/cm2. Uniformly distributed carrier concentration profiles have been formed by electron-beam annealing. 相似文献
53.
We have developed a very-low-loss optical fibre employing silicone resin as the cladding and fused silica as the core. The minimum transmission loss was 3.2 dB/km at 0.84 ?m and the half-pulse width spread was 19 ns/km at 0.80 ?m. 相似文献
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Five years have passed since the invention of the VAD technique. Fabrication techniques for the various kinds of VAD fibers such as graded index fibers, single-mode fibers, high NA fibers, and single polarization fibers have been developed. This paper mainly outlines the recent improvements in the VAD fiber manufacturing techniques such as the preform fabrication technique, dehydration technique, refractive index profile formation technique, and the single-mode fiber manufacturing technique. 相似文献
56.
K Kubo Y Kohara Y Yoshimura Y Inada Y Shibouta Y Furukawa T Kato K Nishikawa T Naka 《Canadian Metallurgical Quarterly》1993,36(16):2343-2349
In order to improve the oral bioavailability (BA) of 2-butyl-1-[[2'-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]-1H-benzimid azole - 7-carboxylic acid (3: CV-11194) and 2-ethoxy-1-[[2'-(1H-tetrazol-5-yl)biphenyl-4- yl]methyl]-1H-benzimidazole-7-carboxylic acid (4: CV-11974), novel angiotensin II (AII) receptor antagonists, chemical modification to yield prodrugs has been examined. After selective tritylation of the tetrazole rings in 3 and 4, treatment of N-tritylated benzimidazole-7-carboxylic acids (6, 7) with a variety of alkyl halides, followed by deprotection with hydrochloric acid, afforded esters of 3 and 4. Mainly 1-(acyloxy)alkyl esters and 1-[(alkoxycarbonyl)oxy]alkyl esters, double ester derivatives, were synthesized. Their inhibitory effect on AII-induced pressor response in rats and oral BA were investigated. (Pivaloyloxy)methyl and (+/-)-1-[[(cyclohexyloxy)-carbonyl]oxy]ethyl esters of 3 and 4 showed marked increases in oral bioavailability which significantly potentiated the inhibitory effect of the parent compounds on AII-induced pressor response. Among them, (+/-)-1-[[(cyclohexyloxy)carbonyl]oxy]ethyl 2- ethoxy-1-[[2'-(1H-tetrazol-5-yl)biphenyl-4-yl]methyl]-1H-benzimida zole- 7-carboxylate (10s, TCV-116) was selected as a candidate for clinical evaluation. 相似文献
57.
K Yamada C Inada S Otabe N Takane H Hayashi K Nonaka 《Canadian Metallurgical Quarterly》1993,128(4):379-384
We investigated the effect of free radical scavengers on the actions of cytokines on islet cells. Interferon-gamma and tumor necrosis factor-alpha reduced the nicotinamide adenine dinucleotide content of mouse islet cells; the combination of interferon-gamma (4 x 10(5) U/l) and tumor necrosis factor-alpha (4 x 10(5) U/l) caused nicotinamide adenine dinucleotide reduction by approximately 40%. Dimethyl urea and dimethyl sulfoxide prevented the decrease, whereas superoxide dismutase, catalase, and mannitol were not effective. Dimethyl urea and dimethyl sulfoxide protected islet cells from the synergistic cytotoxic action of interferon-gamma and tumor necrosis factor-alpha. Major histocompatibility complex class II antigen induction by interferon-gamma and tumor necrosis factor-alpha was also inhibited by dimethyl urea and dimethyl sulfoxide, but not by superoxide dismutase, catalase and mannitol. Since superoxide dismutase of a membrane-penetrable form attenuated the class II antigen induction, the inefficiency of superoxide dismutase, catalase and mannitol may be attributable to their inability to penetrate islet cells. These results suggest that the intracellular generation of free oxygen radicals is involved in islet cell cytotoxicity and class II molecule expression by interferon-gamma and tumor necrosis factor-alpha, and that nicotinamide adenine dinucleotide reduction may be associated with islet cell dysfunction caused by the cytokines. 相似文献
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Wave conversion materials with high thermal conductivity are necessary for high-power semiconductor lighting. Ceramics have higher thermal conductivity than existing matrices such as resin or glass in which phosphor particles are dispersed. However, the high densification of ceramics generally requires high-temperature sintering, which degrades and alters the phosphor particles. In this study, we aimed to achieve the high densification of MgO ceramics at room temperature. Applying high hydrostatic pressure with water addition improved the sample packing ratio and promoted the formation of Mg(OH)2. As a result, the relative density was ≥95%. Additionally, various nitride phosphor particles (CaAlSiN3:Eu2+, β-SiAlON:Eu2+, and α-SiAlON:Eu2+) were dispersed in the MgO matrix at room temperature without degrading the luminescence property. The thermal conductivity of the obtained sample was about 8 W m?1K?1, 40 times higher than that of the epoxy matrix. 相似文献
60.