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161.
The performance of polysilicon thin-film transistors (TFTs) formed by a 600°C process was improved using a two-layer gate insulator of photochemical-assisted vapor deposition (photo-CVD) SiO2 and atmospheric-pressure chemical vapor deposition (APCVD) SiO2. The photo-CVD SiO2, 100 Å thick, was deposited on polysilicon and followed by APCVD SiO2 of 1000 Å thickness. The TFT had a threshold voltage of 8.3 V and a field-effect mobility of 35 cm2/V-s, which were higher than those of the conventional TFT with a single-layer gate SiO2 of APCVD. Hydrogenation by hydrogen plasma was more effective for the new TFT than for the conventional device 相似文献
162.
A single intravenous injection of 4-hydroxyaminoquinoline-1-oxide (4HAQO) to rats induces multiple atypical acinar cell nodules in the pancreas. In this study, the ultrastructure of cells in these nodules was examined at 6, 9, and 12 months, and the features were compared to those of developing embryonal pancreas. The cells in the nodules are exocrine acinar cells in type and exhibited several features which distinguish them from the nonnodular acinar cells. Irregular nuclear shape with enlarged nucleoli was frequently observed. Zymogen granules in the nodular cells appeared as vesicles with contents of extreme electrom lucency and their ultrastructural appearance was similar to those of developing embryonic pancreatic acinar cells at 16 and 18 days of gestation. At the cell periphery, the lateral cell membrane showed bizarre interdigitation and the ectoplasm showed hyaloplasmic rarefaction. These findings indicate that the acinar cell nodules induced by 4-hydroxyaminoquinoline-1-oxide are composed of a new population of phenotypically altered acinar cells showing nuclear abnormalities, modified cell to cell interaction, and a possible defect in synthesis and/or maturation of secretory enzymes. The latter may indicate an arrest in the differentiation of acinar cells. The significance of these findings is discusses, and it is suggested that the atypical nodules in the pancreas induced by 4-hydroxyaminoquinoline-1-oxide may represent early neoplastic foci. 相似文献
163.
The fluctuation propagator for the superconducting order parameter belowT c is derived for a gapless superconductor. The fluctuation of the order parameter consists of two distinct modes: the fluctuations of the phase and the modulus of the order parameter. The former fluctuation obeys a phononlike dispersion, while the latter fluctuation is described by a damping diffusion type equation. The present theory gives an account of the fluctuation-induced Josephson effect belowT c observed recently by Carlson and Goldman. 相似文献
164.
Taniguchi M Kato K Shimauchi A Ping X Nakayama H Fujita K Tanaka T Tarui Y Hirasawa E 《Journal of Bioscience and Bioengineering》2005,99(3):245-251
Cross-linked poly-gamma-glutamic acid (C-L gamma-PGA) markedly purified polluted water collected from rivers and ponds by flocculation and precipitation. This effect of C-L gamma-PGA occasionally required pretreatment with polyaluminum chloride (PAC). Components of polluted water in rivers or ponds are generally thought to be clay minerals, microorganisms and chemical compounds. In this study, the flocculating activities of C-L gamma-PGA against suspensions of bentonite, diatomaceous earth, Escherichia coli and Mycrocystis aeruginosa, and against solutions of crystal violet and bisphenol A were investigated. The mode of action of C-L gamma-PGA is thought to be based on electrostatic interaction between flocculants, C-L gamma-PGA and PAC, and the surface of polluted water components, which may lead to neutralization of the zeta-potential of those components. 相似文献
165.
166.
167.
Sorbistin, a new aminoglycoside antibiotic complex of bacterial origin. III. Structure determination
M Konishi S Kamata T Tsuno K Numata H Tsukiura 《Canadian Metallurgical Quarterly》1976,29(11):1152-1162
The structures of sorbistins A1, A2, B, C and D have been determined including stereo-chemistry. Sorbistins A1, A2 and B are composed of a 4-acyl-amino-4-deoxy-D-glucose and 1,4-diamino-1,4-dideoxy-D-sorbitol, the latter compound being hitherto undescribed in literature. Sorbistins C and D have the same aglycone of 1,4-diamino-1,4-dideoxy-D-sorbitol, which is linked with D-glucose and 4-amino-4-deoxy-D-glucose, respectively, through a glycosidic bond. 相似文献
168.
To define the etiologic factors of Japanese cerebrovascular diseases, a pathological research was conducted on autopsy cases of stroke in Akita Prefecture. In most cases of cerebral hemorrhages, especially in the middle age group (30-59 of age), arteriosclerotic deviations in basal berebral arteries of the circle of Willis and intracerebral small arteries are not found. The authors conclude that cerebral hemorrhage may occur without relationship to disturbances of lipid metabolism, biochemically, and to atherosclerosis, pathologically. Concerning cerebral infarction, especially in the old generation (over 60 years of age), severe arteriosclerotic deviations were recognized both in basal cerebral and intracerebral arteries. These changes were highly influenced by the grade and duration of hypertension, and rarely influenced by hypercholesterolemia. According to the above-mentioned facts, the results obtained from out epidemiological survey were confirmed by the pathological studies. 相似文献
169.
Shintaro Fudano Yoji Miyabata Kazuo Konishi 《Journal of the American Oil Chemists' Society》1974,51(11):514-515
The low condensed components in the condensates of mixtures of β-naphthalenesulfonic acid and β-methylnaphthalenesulfonic
acid with formaldehyde were analyzed by high speed liquid chromatography. The main components of monomer and dimer were β-naphthalenesulfonic
acid and the dimeric condensate of β-naphthalenesulfonic acid, respectively. 相似文献
170.