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排序方式: 共有480条查询结果,搜索用时 15 毫秒
61.
Seiichi Suda Koichi Kawahara Mitsunobu Kawano Hiroyuki Yoshida Toru Inagaki 《Journal of the American Ceramic Society》2007,90(4):1094-1100
Matrix-type nickel oxide (NiO)/samarium-doped ceria (SDC) composite particles, in which NiO and SDC nano-particles were homogeneously dispersed, were synthesized by spray pyrolysis (SP) for an anode precursor of intermediate-temperature solid oxide fuel cells (IT-SOFCs). SP of an aqueous solution containing Ni, Ce, and Sm salts resulted in capsule-type composite particles that had NiO enveloped with SDC. The capsule-type composite particles actually prevent Ni aggregation between particles, but they cannot have a large contact area between nickel (Ni) and SDC. A matrix-type composite particle is expected to have a large contact area because the matrix-type composite is comprised of nanometer-sized Ni and SDC particles. An adequate addition of ethylene glycol successfully resulted in matrix-type NiO/SDC composite particles. The matrix-type composite particles also showed higher anode performance than the capsule-type composite particles in these experiments and they were effective as precursors of high-performance IT-SOFC anodes. 相似文献
62.
N Hasejima H Kobayashi S Takezawa K Yamato C Kadoyama Y Kawano 《Canadian Metallurgical Quarterly》1995,33(10):1105-1110
A 24-year-old man was admitted to our hospital because of exertional dyspnea and abnormal shadows on chest X-ray film. He worked in a factory, where he was exposed to 1.8% beryllium-copper alloys. His job was to draw out heated beryllium-copper wire to make it more fine. Chest X-ray film and chest CT scan showed left-sided pneumothorax, diffuse fine reticulonodular shadows, and several cysts. Pulmonary-function tests showed a restrictive disorder and a low diffusing capacity. A specimen obtained by open-lung biopsy showed epithelioid cell granuloma and alveolitis, which were compatible with chronic beryllium disease. The beryllium content of the lung tissue was 0.045 microgram/gram. Beryllium lymphocyte transformation tests on blood and on bronchoalveolar lavage fluid were positive. Based on these findings, chronic beryllium disease was diagnosed. After treatment with 1 mg/kg of prednisolone daily, dyspnea disappeared. Then the dose was tapered slowly. In Japan, chronic beryllium disease is extremely rare, and to our knowledge only 22 other cases have been reported. 相似文献
63.
H Muratani K Fukiyama T Kamiyama Y Kimura K Abe M Ishii J Fujii I Kuwajima T Shiomi Y Kawano H Mikami S Ibayashi T Omae 《Canadian Metallurgical Quarterly》1996,19(4):281-290
To assess how elderly Japanese hypertensive patients are treated by specialists, we conducted a cross-sectional survey. A total of 1,163 outpatients aged 50 years or older were studied. Hypertension was diagnosed in 939 of these patients, and 827 were receiving drug therapy. The average blood pressure during therapy was 143 +/- 16/81 +/- 10 mmHg. In patients aged 70 years or older, systolic blood pressure during antihypertensive therapy was significantly higher (p < 0.01) and diastolic blood pressure was significantly lower (p < 0.01) than the corresponding values in those aged 50 to 59 years or 60 to 69 years. The calculated mean blood pressures were similar in the different age groups. The rate of monotherapy in the patients aged 70 years or older was 58.8%, which was significantly higher (p < 0.01) than the rates of monotherapy in the other age groups. Calcium channel blockers were prescribed in about 80% of patients, irrespective of age or comorbidity. Of the patients receiving calcium channel blockers, 43.5% were treated with monotherapy. This rate significantly (p < 0.01) increased with advancing age. Diastolic blood pressures were significantly lower (p < 0.05) in patients with stroke and in those with ischemic heart disease, diabetes mellitus, or dyslipidemia, as compared with patients with no comorbidity. Among patients aged 70 years or older, the difference in systolic blood pressure between those with ischemic heart disease and those with no comorbidity was not significant. Blood pressure in elderly hypertensive patients was reduced to a level similar to that in younger patients. The target blood pressure was influenced by the presence of comorbidity. Furthermore, specialists showed a high preference for the use of calcium channel blockers in the management of hypertension. 相似文献
64.
65.
Kawano MS Heidemann BR Cardoso TK Possetti GR Kamikawachi RC Muller M Fabris JL 《Applied optics》2012,51(12):2015-2022
Three approaches that allow the tailoring of long period gratings based refractometric sensors for concentration measurement in fuel blends are employed to assess the fuel quality in biodiesel and biodiesel-petrodiesel blend. To allow the analysis of fuel samples with refractive index higher than fiber cladding one, the samples refractive indices were changed by thermo-optic effect and by dilution in a standard substance with low refractive index. The obtained results show the sensor can detect oil concentration in biodiesel samples with resolution as better as 0.07% and biodiesel concentration in biodiesel-petrodiesel samples with average resolution of 0.09%. 相似文献
66.
The current work expresses considerations about some of the differences of the fused flux CIS-F10 obtained by means of fragmentation in water and with an air jet. The comparisons are established taking into account their respective granulometric distributions, shapes and grain densities, as well as the energy and the time spent in the process of obtaining each of these variants. Criteria for the physical process of flux fragmentation with an air jet and its influence over the aspects formerly mentioned are also included. The principal findings were that the process for obtaining the fused flux CIS-F10 granulated with an air jet consumes 37% less energy and 25% less time than the one performed with pouring water. The solidness grade of the spherical grains, granulated with air, (with pycnometric density 2.31 g/cm3), with a granulometric distribution more continuous than that of the granules in water, contributes to the increase of the apparent density (11%) of the flux and promotes the creation of artificial granulometric distributions, counteracting the rolling effect during welding. 相似文献
67.
Imoto Taiji; Ueda Tadashi; Tamura Tomohiro; Isakari Yoshimasa; Abe Yoshito; Inoue Makoto; Miki Takeyoshi; Kawano Keiichi; Yamada Hidenori 《Protein engineering, design & selection : PEDS》1994,7(6):743-748
Mutations around His15 which lie far away from the active site,stimulated glycol chitin activity of lysozyme at physiologicaltemperature. Del-Argl4Hisl5 lysozyme, a mutant lysozyme whoseArgl4 and Hisl5 were deleted together, and has the highest activityamong these mutant lysozymes, had a similar binding abilityto a trimer of N-acetyl-glucosamine, a substrate analogue, relativeto native lysozyme. This suggests that the increased activitywas due to an increased kcat in the catalysis reaction. TheH-D exchange rate of the N-1 proton in the Trp63 which is locatedin the active site cleft, was enhanced in the Del-Argl4Hisl5lysozyme, while 2-D proton NMR analysis revealed no conformationalchange around Trp63. We conclude that some sort of fluctuationat the active site might be required for the manifestation ofactivity. This theory is supported by the finding that the Del-Argl4Hisl5lysozyme showed a shift in temperature dependency of activityto lower temperatures compared with that of native lysozyme. 相似文献
68.
In steel members strengthened by carbon-fiber reinforced polymer (CFRP) plates, the thermal stresses are introduced in the steel members, the CFRP plates and the adhesive layers when temperature changes because the linear thermal expansion coefficients of steel and CFRP are mismatched. As so far, the authors proposed a technique to reduce the thermal stress in steel members strengthened by CFRP plates, which involves bonding aluminum alloy plates with CFRP plates. In the proposed method, the thermal stress in steel member can be reduced so that there are negligible levels of stress in steel member when the cross sectional areas of CFRP and aluminum plates are designed to correspond to the coefficient of thermal expansion of steel, even though the thermal stresses are introduced in the CFRP and aluminum plates. In this study, to confirm the maintaining the thermal stress reduction in steel member by proposed method, thermal stress measurement in steel plate strengthened by CFRP and aluminum plates was carried out about 21 months. In this research, the thermal stress introduced in the steel plate strengthened by CFRP plates was also measured. Furthermore, to assume the thermal shear and normal (peel) stresses in adhesive layers, FE analysis with plane stress element was employed. As the result, it was shown the thermal stresses in steel plate with CFRP plate were able to calculate by using composite theory and measured temperature. Furthermore, in steel plate strengthened by CFRP and aluminum plates, the thermal stress introduced in steel plate was negligible-small through the all-season. It was found the thermal stresses in steel plate with CFRP plates as well as CFRP and aluminum plates were also estimated by using composite theory and measured temperature. In the steel plate strengthened by CFRP and aluminum plates, the thermal shear and normal stresses in adhesive layer glued to steel plate become smaller than that in the conventional CFRP bonded specimen. However, the shear stress in adhesive layers between CFRP and aluminum plates in proposed method was higher than the thermal stress in adhesive layers between CFRP plates in conventional method. 相似文献
69.
Characteristics of sol-gel derived PZT thin films with lead oxide cover layers and lead titanate interlayers 总被引:1,自引:0,他引:1
The sol-gel derived PbZr0.53Ti0.47O3 (PZT) films were fabricated on the bare Pt/Ti/SiO2/Si substrates or the same substrates coated by the PbTiO3 (PT) interlayers. The post-deposition annealing temperature and time were optimized when the PbO cover layers and PbO vapour-containing atmosphere were compared with each other and adopted as the method to diminish the lead-loss problem during the high-temperature post-deposition annealing. The X-ray diffraction patterns, microstructures, and electrical properties such as relative permittivity, r, remanent polarization, P
r, and coercive electrical field, E
c, were investigated in relation to the annealing conditions. The PZT films deposited on the bare Pt/Ti/SiO2/Si substrates under the PbO vapour-containing atmosphere showed better electrical properties. This indicates that the PbO vapour-containing atmosphere may be the better method of lead-loss-prevention to process the lead-containing films rather than the PbO cover layer method. The electrical characteristics of the PZT films, r=1150, a dissipation factor of 0.039, P
r=26 C cm–2, and E
c=40.5 kV cm–1 were measured at 1 kHz. When PZT films were deposited on substrates coated by the PT layers, PZT-PT films with single perovskite phase were derived by post-deposition annealing at 500 °C for 1 h. However, the relative electrical properties are very poor, i.e. E
r=160, P
r=2.0 C cm–2 and E
c=75 kVcm–1. The optimum combination for preparing PZT-PT films is a 40 nm PbTiO3 interlayer and annealing conditions of 6 h at 550 °C in a PbO vapour-containing atmosphere; the derived films exhibit electrical properties of E
r=885, P
r=21.5 C cm–2 and E
c=64 kV cm–1. The combination of inserting a PT interlayer and annealing in a PbO vapour-containing atmosphere can prevent the formation of electrical short paths. In this case, nearly pin-hole-free PZT films can be grown on the PT (interlayer) /Pt/Ti/SiO2/Si substrates. It is believed that it is possible to prepare the PZT films with nano-scale uniformity, reproducible quality, which may be worth considering for commercial applications. 相似文献
70.
The dynamic characteristics involved in the loading process in the ocean environment are extremely complicated and difficult
for exact evaluation. In this paper, parametric studies are presented to assess the influence of uncertainties associated
with various assumptions and approximations, involved in modelling the dynamic loading processes of ocean environment, for
the evaluation of dynamic response of offshore structures. These uncertainties are represented by the inertia coefficient
and the drag coefficient of the Morison equation which defines the wave forcing function, the mean height of the input sea
waves and the shear wave velocity of the soil. The results show that the effects of uncertainties are closely related to the
natural frequency of the structure and the predominant frequency of the wave force. These uncertainties, except the variation
in the shear wave velocity in the soil, contribute significantly to the dynamic response and the first passage probability
evaluation of the offshore structure systems. 相似文献