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991.
Application of a high magnetic field in the carbonization process to increase the strength of carbon fibers 总被引:1,自引:0,他引:1
Mun Gyu Sung Kensuke SassaTetsuya Tagawa Takashi MiyataHiroyasu Ogawa Masao DoyamaShigehiko Yamada Shigeo Asai 《Carbon》2002,40(11):2013-2020
Carbon fibers produced from PAN (polyacrylonitrile) as a precursor are generally subjected to the three heat treatment processes of stabilization and carbonization followed by graphitization. Stabilized fibers were carbonized in a high magnetic field of 5 T imposed parallel to the fiber axis at a temperature of 1445 K and graphitized without a magnetic field at 2273 K. The tensile strength of these treated fibers is increased by 14% in comparison with those of no magnetic treatment. The reason why the imposition of the magnetic field could improve the strength of the fibers has been studied through microscopic observation of the fiber surface as well as a statistical analysis by use of Weibull distributions. 相似文献
992.
Akimoto T. Suzuki T. Murai I. Narita M. Ogawa Y. 《IEEE transactions on nuclear science》1991,38(5):1040-1043
The authors describe calibration measurements for the efficiency and response function of the NE213 scintillator as an application of a two-dimensional pulse height analysis system. In this method, a 252 Cf spontaneous fission source with a continuous spectrum is employed by taking each fission event as a pulsed neutron source, and the efficiency and response function of the NE213 scintillator can be estimated by two-dimensional measurements of the time-of-flight spectrum (neutron energy spectrum) and pulse height spectrum 相似文献
993.
Two near full-length cDNAs (LE4CL-1, LE4CL-2), which encode 4-coumarate:CoA ligase (4CL), were cloned from a library of Lithospermum erythrorhizon cell suspension cultures by the use of heterologous probe of potato 4CL. These cDNAs are 2.1 kb and 2.2 kb in length, respectively. LE4CL-1 encodes 636 amino acids, whose homologies to the 4CL protein sequences known to potato, parsley, pine and rice, were found to be 68%, 66%, 56% and 50% (identities on amino acid level), respectively, whereas those of the predicted translation product of LE4CL-2 (594 amino acids) to the above 4CL proteins were 49 approximately 54%. The similarity of the deduced amino acid sequences between the two 4CLs from Lithospermum cell cultures was 49% in identity. Northern analyses showed that the mRNA levels of both LE4CL-1 and LE4CL-2 were much higher under illumination than in the dark, as reported for the 4CL genes of such plants as parsley. In comparison of mRNA levels of LE4CL-1 and LE4CL-2, the former was demonstrated to be generally higher than the latter by means of an application of RT-PCR. The genomic southern blot experiments suggested that there are probably three copies of LE4CL-1 in the Lithospermum genome DNA, whereas only one copy was detected for LE4CL-2. 相似文献
994.
995.
K Hayashi N Watanabe S Tanaka M Ogawa S Uchida H Yamanishi K Minami H Abe K Aoki H Kawai 《Canadian Metallurgical Quarterly》1994,14(4):348-349
The patient was a 50-year-old alcoholic man with a left palatine tonsillar ulcer. Histopathological and bacteriological studies established the diagnosis of tonsillar tuberculosis with asymptomatic advanced pulmonary tuberculosis and multiple cerebral supra- and infratentorial tuberculomas previously unnoticed. 相似文献
996.
We reported the first case of chorea-acanthocytosis associated with low glycohemoglobin A1c. Fasting blood sugar, daily profile of blood sugar, serum fructosamine and 75 g glucose tolerance test were all within normal limits. While abnormal hemoglobins were not detected, red blood cell half-life was sharply reduced to 13.4 days. These findings suggest that the low glycohemoglobin A1c in this case is highly ascribable to the reduction of red blood cell half-life rather than to continuous hypoglycemia. However, we can not rule out that the abnormalities of red blood cell membrane, suggested factors in this disease, may be related to the low glycohemoglobin A1c value. Further investigations on chorea-acanthocytosis cases with normal red blood cell half-life are necessary in order to elucidate whether an abnormal glycohemoglobin A1c value is a specific indication regarding this disease. 相似文献
997.
EP37 family proteins are non-lens members of the betagamma-crystallin superfamily, of which expression is observed in integumental tissues of the Japanese newt, Cynops pyrrhogaster. In the present study, a gene was isolated that has high homology with ep37 and is transcribed mainly in the gastric epithelial cells and hence designated gep. The predicted amino acid sequence of the gep cDNA contains four betagamma-crystallin motifs in the N-terminal half, as is the case in the integumental EP37 proteins. Immunohistochemical analysis showed that GEP protein was mainly localized on the luminal content of the surface mucous cells of the gastric epithelium in both premetamorphic larvae and adults. In addition, GEP protein was also expressed in fundic glands after metamorphosis. Considering the fact that beta- and gamma-crystallins are evolutionarily related to stress-induced proteins, this localization suggests that GEP protein may have an evolutionarily conserved role in protection against physico-chemical stresses, such as physical abrasion and autodigestion, during assimilation. 相似文献
998.
We studied T cell responses to four glutathione S transferase (GST)-fused mite antigens prepared in our laboratory using peripheral blood lymphocytes from mite-sensitive patients with bronchial asthma. Of the four recombinant antigens, purified GST-Mag3 had the strongest ability to cause patients' lymphocytes to proliferate, and its potency was almost comparable to that of crude mite bodies (Dfb) and faeces (Dff) antigens and a purified major antigen, Der f 2. The responder lymphocytes were mainly T cells, because the proliferative response was depleted by the treatment of lymphocytes with anti-CD3 antibody and complement, but not with anti-CD20 antibody and complement. The responsiveness of lymphocytes to GST-Mag3 correlated with that to Der f 2, but GST-Mag3 displayed slightly higher activity to stimulate lymphocytes than Der f 2. Simultaneously, the levels of Dff- and GST-Mag3-specific IgE antibodies correlated with the responsiveness of lymphocytes to GST-Mag3. These results suggest that Mag3 is a new valuable antigen for the response of T cell proliferation in mite-sensitive patients. 相似文献
999.
T Morishita S Kobayashi K Sato K Sakae N Ishikawa N Kobayashi Y Noguchi K Akiyoshi T Suga A Ogawa S Noro H Sawada H Kimura A Yamada T Ishizaki N Kamimura A Iwashima T Ono N Tachibana H Sekine N Ohnuki K Kazama K Sadamasu K Ohta K Mise 《Canadian Metallurgical Quarterly》1997,(115):152-154
Preliminary screening of antiviral AIDS drugs has been carried out using three different in vitro assay systems. Among 96 samples of different origin tested, two were shown to inhibit the growth of HIV in vitro. One of the positive samples (plant origin) has hopeful signs, as the ranges of effective doses are wider than those of most of positive samples which had been found by us. 相似文献