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81.
Tritium radioluminography has been applied to determine the hydrogen (H) diffusion coefficients in Ti50Cr50 and Ti40Cr60 alloys, both with two-phase structures of a body-centered cubic (bcc) phase and a Laves phase. Using radioluminography, H distributions in those phases have been observed, and H penetration profiles have been measured. The tritium diffusion coefficients in the Ti50Cr50 and Ti40Cr60 alloys have been successfully determined by analyzing the tritium penetration profiles to be 3.3±0.3 × 10?12 and 1.4±0.1×10?12 m2/s, respectively. These values suggest that the H diffusion in the Laves phase is slower than that in the bcc phase. It is also suggested that H diffuses by short-circuiting diffusion through the interface between the bcc phase and the Laves phase. 相似文献
82.
83.
T Arai K Matsumoto K Saitoh M Ui T Ito M Murakami Y Kanegae I Saito FL Cosset Y Takeuchi H Iba 《Canadian Metallurgical Quarterly》1998,72(2):1115-1121
84.
M Okada T Nakajima N Eizuka Y Saitoh M Yakata 《Computer methods and programs in biomedicine》1988,26(2):105-113
Mapping analysis of cardiokymography is helpful in clarifying the relationship between vibratory pattern and recording sites, but needs a highly stable recording technique. We have therefore studied the stability of recording cardiokymograms, and present here a new method for creating stable maps which enables diagnosis of chest-wall vibration abnormalities. Cardiokymograms were recorded on 16 points of the chest wall located at regular intervals horizontally and vertically. The time interval between a R-wave peak of the electrocardiograms and an E-point of the cardiokymograms were measured for all the 16 records. Isochronal maps in 23 healthy subjects were classified into four types. The map of a patient with myocardial infarction was quite different from any one of the four normal patterns and seemed to show a paradoxical movement of the chest wall. 相似文献
85.
M Tamura A Zama H Kurihara H Fujimaki H Imai T Kano F Saitoh 《Canadian Metallurgical Quarterly》1998,14(11):617-622
Neurofibromatoses are genetic disorders of the nervous system that primarily affect the development and growth of neural cell tissues. These disorders produce other abnormalities such as skin changes and bone deformities. Neurofibromatoses occur in both sexes and in all races and ethnic groups. Scientists have classified these disorders as neurofibromatosis type 1 (NF1) and neurofibromatosis type 2 (NF2). Other types of neurofibromatoses may exist, but are not yet identified. Nearly 50% of the cases shows a well definited familiarity for the disease, according to an autosomal dominant transmission, while the other 50% of patients shows a negative history of familiarity, according to a new chromosomal mutation interesting the same autosomal genes of the dominant transmission. Oral localization is more rare showing an incidence ranging from 4 to 7% in most series of different authors. The most frequent involvement site in oral neurofibromatosis is the tongue, followed by the oral mucosa and floor of the mouth; palate and maxillary-mandibular bones are a rare localization of the disease. In the present, the clinical, radiological, histopathological and therapeutical aspects of a clinical case of neurofibromatosis, presenting as mandibular tumor, are examined. The clinical case reported, a 37 year old man, was essentially characterized by a positive family history for the disease, a neurofibroma of the oral mucosa. 相似文献
86.
A comparative study has been made on the functionality distribution of two hydroxyl terminated polybutadiene products which are used largely as prepolymers for sealants, adhesives, and solid propellants. They are known to possess nearly the same molecular characteristics. To this end, each product was fractionated into 17 fractions with different molecular weights by the preparative GPC technique. Sample fractions thus obtained were subjected to “polarity-controlled adsorption” thin-layer chromatography (TLC) to determine the functionality distribution. From these experimental results it was concluded that a decisive difference between these products consists in the functionality distribution, within a molecular weight range higher than 7000. 相似文献
87.
Y. Aoki Y. Wada A. Ogino M. Saitoh R. Nomura Y. Okuda 《Journal of Low Temperature Physics》2005,138(3-4):783-788
No Heading The transverse acoustic response in the B phase of superfluid 3He has been measured using an AC-cut quartz transducer at a pressure of 17.0 bar. The measurements were performed by a CW bridge method at a frequency of 9.3 MHz utilizing a quadrature hybrid and a high-frequency lock-in amplifier. By sweeping frequency around the resonance frequency of the transducer, in-phase and quadrature responses of the resonance were obtained from the output of the lock-in amplifier. We successfully separated the quality factor and the resonance frequency. Quality factor of the transducer had a small dip just below Tc and increased as n by cooling, while its resonance frequency decreased sharply at Tc and gradually recovered to the normal state value in the low temperature limit.PACS numbers: 67.57.Jj, 43.58.+z. 相似文献
88.
We propose a new method, to our knowledge, for noninvasive scattering measurements of tissues by the use of a pyroelectric polymer transducer, poly(vinylidene fluoride trifluoroethylene) film. In this method, samples are irradiated with nanosecond, low-energy light pulses delivered from an optical fiber, and the pyroelectric signal induced by the diffuse reflectance is measured with a transducer. The signal is then converted into diffuse reflectance by use of a calibration factor. The validity of this method was confirmed by our measuring the scattering coefficient of a white acrylic resin within an accuracy of +/- 15%. We attempted to apply this method to the estimation of scattering coefficients of normal and burned skins in rats in vivo. 相似文献
89.
The antitumor effect and biological activities of a newly synthesized lipid A analogue (ONO-4007) were investigated in a hamster pancreatic carcinoma model. Marked and dose-dependent inhibition of tumor growth was achieved by i.p. injection twice a week for 3 weeks of 10, 30 or 50 mg/kg of ONO-4007. Endogenous tumor necrosis factor (TNF) activities induced by ONO-4007 were significantly greater in tumor than in serum, spleen and liver. TNF production by macrophages stimulated with ONO-4007 after culture was much greater when culture was performed in the presence of hamster pancreatic carcinoma cells (no cell-to-cell contact). It was further found that the cytotoxic activity of TNF secreted by macrophages cultured with cancer cells was inhibited in the presence of anti-TNF neutralizing antibodies. These findings suggest that ONO-4007 displays antitumor effects by stimulating production of endogenous TNF in tumor macrophages, possibly through activation by soluble macrophage-stimulating factors in cancer cells. 相似文献
90.
S Takizawa H Sawada T Someno Y Saitoh H Yokosawa M Hoshi 《Canadian Metallurgical Quarterly》1993,267(1):86-91
The relation between left-ventricular stroke volume (SV) and end-diastolic volume (EDV) was determined based on angiocardiographic measurements in 10 open-chest minipigs under varying filling conditions (blood letting or infusions). The results were compared with a theoretical relation calculated under the assumption of varying EDV but constancy of myocardial properties. In contrast to the linear increase of SV as a function of EDV as found in the animal experiments, the calculated curve reveals a maximum near the normal operating point with a decrease in the range of higher EDV. It can be concluded that the well-known increase of SV with increasing ventricular filling, beyond the normal EDV, is almost completely due to muscle physiological factors (mainly increase in Ca2+ sensitivity of the contractile apparatus), whereas the decrease of SV in the range of low filling pressure is mainly due to the geometrical conditions. 相似文献