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201.
Noninvasive Measurement of the Volume Elastic Modulus in Finger Arteries Using Photoelectric Plethysmography 总被引:2,自引:0,他引:2
Shimazu Hideaki Yamakoshi Ken-Ichi Kamiya Akira 《IEEE transactions on bio-medical engineering》1986,(8):795-798
A method for the nonivasive measurement of the volume elastic modulus (Ev) in human finger arteries was developed. The volume change ratio and pulse pressure in the arteries were simultaneously determined by a transmittance type infrared photoelectric plethysmograph and a volume oscillometric sphygmomanometer using an occlusive cuff. The Ev values could be obtained at a desired transmural pressure level of the arteries which was controlled by the cuff. A clear difference was revealed between the Ev values obtained in the fingers of two male subjects of 33 and 65 years old. The values determined by this method were compared to those calculated from pulse wave propagation velocity (Evp) obtained simultaneously in the fingers of 11 subjects. The linear regression equation was Ev = 1.31 Evp ?0.117 with a correlation coefficient r = 0.893 (n = 39). These results suggest that this should be a useful and noninvasive method of evaluating changes in arterial elasticity accompanying aging and perhaps influenced by accompanying hypertension or arteriosclerosis. 相似文献
202.
In this paper, the numerical analysis is given which is applicable for a TEA-CO2 laser pumping in search of effective pumping method. The analysis also can estimate the optimum pressure for a given molecule and a given pulse laser. Also we report in this work many FIR laser emissions from population inversion transition which have never observed before using a TEA-CO2 laser. 相似文献
203.
Improved Filtration Performance of Continuous Alumina-fiber-reinforced Mullite Composites for Hot-Gas Cleaning 总被引:1,自引:0,他引:1
Satoshi Kitaoka Naoki Kawashima Yoshinobu Komatsubara Akira Yamaguchi Hisao Suzuki 《Journal of the American Ceramic Society》2005,88(1):45-50
The effect of filtration layer morphology on filtration performance at 673 K was investigated for continuous alumina-fiber-reinforced mullite composite filters that capture fly ash on their outer surfaces. Two types of filtration layers were prepared on the outer surfaces: a mono-layer consisting of mullite agglomerated particulates and a bi-layer, with mullite whiskers formed by a vapor-phase reaction and strongly adhered to the particulates exposed on the outer surfaces. For filters with mono-filtration layers, the filtration efficiency was improved slightly by increasing the filtration layer thickness. However, the maximum differential pressure increased during the filtration tests. Adhesion of whiskers to the outer surface decreased the maximum differential pressure to about one-third less than that with the mono-filtration layer. This low differential pressure remained constant throughout the duration of the test, with corresponding increases in filtration efficiency. 相似文献
204.
Akira Doi 《Journal of Materials Science》1989,24(2):749-755
From the analysis of complex impedance and admittance data of (Agl)75(Ag4P2O7)25 glass, an Ag+-ion conductor, it was revealed that the sample can be approximated by a seriesRC
1 circuit at high temperature, with the capacitorC
1 arising from the charge-carrier depleted region near the anode which develops as conduction proceeds, and by a parallelRC
2 circuit at low temperature, with the capacitorC
2 arising from the saturated value for ionic polarization of, say, the silver-iodine pairs as well as from the relaxation effect of the Ag+ ions for conduction. TheC
1 andC
2 values were found to be almost temperature-independent at peak frequencies of the distorted semicircles in respective complex planes, with the ratioC
1/C
2 as large as 104. 相似文献
205.
206.
207.
The electrical properties of 1.7-MeV-electron-irradiated sulfur (S)-doped GaP were studied by using Hall effect and resistivity measurements. It was found that the concentration of S donors decreased and the deep acceptors were introduced by 1.7-MeV electron irradiation. The decrease of the concentration of S donors could be understood by considering the formation of a complex center of radiation-produced defects with S. A complex center acted as a deep acceptor and recovered in the stage centered at 150°C anneal. The introduction rate of this center was ~2.1 cm-1. From the isothermal annealing experiments, it was found that the recovery for this center approximately obeyed first-order kinetics and its activation energy was ~1.7 eV. Furthermore, another complex center involving S, which was a non-compensating defect in n-type GaP, was introduced. This center was seemed to be a deep donor. 相似文献
208.
Zhanpeng Lu Tetsuo Shoji Yoichi Takeda Yuzuru Ito Akira Kai Seiya Yamazaki 《Corrosion Science》2008,50(2):561-575
The stress corrosion cracking (SCC) growth kinetics for a cold worked 316L stainless steel was continuously monitored in high purity water at different temperatures and dissolved oxygen (DO) levels under a K (or Kmax) of 30 MPa m0.5. The total SCC test time was more than 8000 h to make sure the steady state crack growth rate under each test condition could be reached. Crack growth rate (CGR) increases with increasing temperature in the range 110-288 °C. A typical intergranular-cracking mode is identified. Depending on the previous test condition, especially the temperature, three kinds of crack growth kinetics, i.e., increasing with testing time then becoming steady, being constant during the whole period, or decreasing with test time then becoming steady, are identified and discussed. Time-dependent and testing history-dependent crack growth modes were confirmed in two series of tests in 2 ppm DO and 7.5 ppm DO pure water. The apparent activation energies are calculated and compared with other data in different environments under different applied loading levels for understanding the cracking mechanism. 相似文献
209.
Some tetracycline (TC) antibiotics, including TC and anhydrotetracycline, have been found to enhance specific binding of low
density lipoprotein (LDL) to both LDL receptor-positive and-negative cells at relatively higher concentrations. When incubated
at 37°C, the ability of LDL receptor-negative human fibroblasts to bind 125I-LDL was increased from<2 to 45 ng/mg by 170 μM TC. In normal human fibroblasts and Hep G2 cells, 125I-LDL binding was elevated 1.4- to 2-fold by 113 μM TC. The 125I-LDL binding in the presence of TC was diminished by both heparin and EDTA. The enhancement by TC was not observed when 125I-LDL binding was assayed at 4°C. TC enhanced LDL binding to paraformaldehyde-fixed Hep G2 cells, excluding LDL receptor induction
in the mechanism. These results demonstrated that TC enhanced cellular LDL binding through a process not involving functional
LDL receptors. 相似文献