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361.
Journal of Infrared, Millimeter, and Terahertz Waves - We have analyzed coupling properties of the coupled microstrip lines whose substrate contain electron-hole plasma by means of the spectral...  相似文献   
362.
This paper presents information on the preparation of the network polyester films from glycerol (Yg) and aromatic dicarboxylic acids of phthalic anhydride (P), dimethyl isophthalate (I) and dimethyl terephthalate (T), as well as aliphatic dicarboxylic acids of adipic, sebacic, 1, 10-decanedicarboxylic and 1, 12-dodecanedicarboxylic acids, and their properties. Yg and dicarboxylic acid were polycondensed immediately before the gelation started. The prepolymers obtained were cast from DMF solution and successively post-polymerized at various temperatures and times to form networks. The resultant films were transparent, flexible and insoluble in organic solvents. Heat distortion temperature (Th) measured by a penetration mode of thermomechanical analysis increased with increasing post-polymerization temperature and time, and then leveled out. Th values corresponded well to the glass transition temperature (Tg) measured by differential thermal analysis (DTA). Th was 152°C, 162°C and 197°C for YgP, YgI and Yg T post-polymerized at 270°C for 6 h, respectively. Th values of network films made from aliphatic dicarboxylic acids could not be observed until complete probe penetration occurs, as a result of thermal decomposition because the Tg is lower than room temperature. The degree of reaction estimated from the IR absorbance of hydroxyl and methylene groups was in the range of 60–80%. Two diffraction peaks appeared in the wide-angle X-ray scattering pattern, suggesting some ordered structure owing to the regular networks. Density decreased with increasing post-polymerization time and temperature, in the order YgP > YgI > YgT. Network films made from aliphatic dicarboxylic acids had much lower tensile strength and Young's modulus, and greater elongation, than those made from dicarboxylic acids, as a result of the Tg being below room temperature.  相似文献   
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An experimental study of performance of the disk MHD generator with argon was carried out using a shock‐tube driven facility. An inlet swirl was introduced in the MHD channel in order to improve the enthalpy extraction and the isentropic efficiency. The experimental results were compared with those of the disk MHD generator without the inlet swirl. A high enthalpy extraction of 25.7% was obtained and the highest isentropic efficiency for argon was achieved at the same time in the present experiment. The measured static pressure in the MHD channel was kept lower than that without the inlet swirl. This has suggested that the introduction of the inlet swirl reduces the retarding force for the flow and that the increase of the enthalpy extraction is ascribed to the increase of the flow velocity and of the electrical efficiency. Furthermore, the flow without shock wave was observed at low seed fractions and low load resistances. At the same time, it was found for the first time that when there was no shock wave, the isentropic efficiency became higher than that with the shock wave. © 2002 Wiley Periodicals, Inc. Electr Eng Jpn, 141(1): 18–25, 2002; Published online in Wiley InterScience ( www.interscience.wiley.com ). DOI 10.1002/eej.10045  相似文献   
366.
OBJECTIVE: To investigate whether anticardiolipin antibodies (aCL) in patients with systemic lupus erythematosus (SLE) bind to beta 2-glycoprotein I (beta 2GPI), and to search for a relationship between the presence of IgG and/or IgM anti-beta 2GPI antibody and clinical manifestations in SLE patients. METHODS: IgG and IgM anti-beta 2GPI in 308 Japanese SLE patients were measured using phospholipid-independent enzyme immunoassays. Relationships to clinical histories and to various laboratory data were examined. RESULTS: The values of anti-beta 2GPI and aCL, as measured by conventional enzyme immunoassay, showed a strong correlation, but the anti-beta 2GPI assay was more useful in distinguishing beta 2GPI-dependent aCL from beta 2GPI-independent aCL. The presence of IgG anti-beta 2GPI was associated with an increased frequency of a history of thrombosis. Comparisons of various laboratory data suggested that the titer of anti-beta 2GPI may fluctuate with disease activity. CONCLUSION: The results suggest that pathogenic aCL is directed against structurally altered beta 2GPI and that enzyme immunoassay for anti-beta 2GPI may prove useful in evaluating the risk of thrombosis and monitoring the clinical course in patients with SLE.  相似文献   
367.
Recently, hepatitis GB virus C (HGBV-C) has been recovered from patients with non-A-E hepatitis. However, it has been unclear whether HGBV-C may be related to the development of alcoholic liver disease (ALD) or not. In this study, we determined HGBV-C RNA in sera from alcoholic patients without markers for hepatitis C and B viruses to evaluate the role of HGBV-C in ALD. Serum samples were obtained from 68 patients with ALD and 40 nonalcoholic patients with chronic type C liver disease. HGBV-C RNA was detected in only 3 of 68 (4.4%) patients with ALD, in 2 of 27 patients with hepatic fibrosis, and in 1 of 5 patients with chronic hepatitis. There was no HGBV-C RNA in sera from patients with fatty liver, alcoholic hepatitis, or cirrhosis. Serum levels of AST, ALT, and gamma-glutamyltranspeptidase in alcoholic patients with, as well as without, HGBV-C RNA decreased to normal levels after abstinence. In addition, an inflammatory change was not observed in liver biopsy specimens obtained from two HGBV-C-positive patients with alcoholic hepatic fibrosis. Our results clearly suggest that the prevalence of HGBV-C infection in patients with ALD is rare and that HGBV-C may not play an important role in the development of liver disease in alcoholics.  相似文献   
368.
The effects of the non-steroidal anti-inflammatory drug (NSAID) piroxicam and the carotenoids lycopene and beta-carotene, alone or in combination, on the development of rat superficial urinary bladder carcinomas induced by N-butyl-N-(4-hydroxybutyl)nitrosamine (BBN) were studied. Male Fischer 344 rats, 6 weeks old, were given 0.05% BBN in the drinking water for 8 weeks followed by administration of piroxicam (0.0075% in the diet), lycopene (0.0025% in the drinking water) and/or beta-carotene (0.0025% in the drinking water) for 12 weeks, then killed for histological analysis of urinary bladder lesions. Cell proliferation potential was analyzed by immunohistochemical staining of the proliferative cell nuclear antigen (PCNA). Piroxicam alone, piroxicam+lycopene, and piroxicam +lycopene+ beta-carotene all significantly decreased the incidences and numbers of transitional cell carcinomas (TCCs), but the combination of piroxicam with carotenoids did not result in a clear improvement in the preventive potential of piroxicam. Piroxicam+ beta-carotene also caused a significant reduction and lycopene alone a slight but not significant reduction in the number of TCCs. In contrast, beta-carotene alone and lycopene+ beta-carotene were without inhibitory influence on any of the lesion categories examined, and the latter significantly increased the proportion of high-grade TCCs. Nevertheless, all of the chemopreventive agents, either alone or in combination, significantly decreased the TCC PCNA index, the effect extending to the surrounding epithelium in the piroxicam+lycopene and piroxicam+lycopene+beta-carotene groups. These results indicate that the NSAID piroxicam may be a more effective chemopreventive agent than lycopene and beta-carotene for superficial urinary bladder carcinogenesis.  相似文献   
369.
Computer simulation is used to analyze the short-range order hardening (SROH) effect in Cu-25 at. pct Au. It is confirmed that the subsequent dislocations randomize the state of order of a system. O. SASAKI, formerly with Dai Nippon Printing Company, Tokyo 162 K. WATANABE, formerly with the Department of Metallurgical Engineering, Hokkaido University  相似文献   
370.
Inclusion polymerization of cyclic diene monomers, such as cyclopentadiene, 1,3-cyclohexadiene, 1,3-cycloheptadiene, 1,5-cyclooctadiene, and 2,5-norbornadiene, was studied, using deoxycholic acid (DCA) as the canal component. The formation of monomer-DCA adducts was observed, however, the polymerization occurred only in the case of cyclopentadiene, 1,3-cyclohexadiene, or 1,3-cycloheptadiene. The polymers obtained consisted preferably of 1,4-units and almost 100% of 1,4-units in the case of 1,3-cyclohexadiene. ESR measurements revealed that inclusion polymerization of cyclopentadiene or 1,3-cyclohexadiene in DCA canals proceeds by a free radical mechanism.  相似文献   
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