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51.
52.
Myo Than Htay Yuji Tani Yoshio Hashimoto Kentaro Ito 《Journal of Materials Science: Materials in Electronics》2009,20(Z1):341-345
ZnO nanowires were grown by an ultrasonic spray pyrolysis technique. The aspect ratio and size of the wire were dependent
mainly on the pH value of a precursor solution and the growth temperature. By high-resolution transmission electron microscopic
analysis and photoluminescence measurements, it was confirmed that the nanowires are monocrystalline with good optical quality. 相似文献
53.
Kentaro Shinoda Shanshan LiangSanjay Sampath Richard J. Gambino 《Materials Science and Engineering: B》2011,176(1):22-31
Magnetic properties of manganese zinc ferrite (MZF) coatings deposited by atmospheric dc plasma spraying largely depend on zinc and oxygen loss during particle flight. The temperature and velocity of in-flight MZF particles were widely varied by changing plasma spray conditions to examine these chemistry changes and resultant magnetic properties. Zn loss increases with increased particle temperature or decreased particle velocity. Meanwhile, wüstite (FeO) formation, related to the oxygen loss, is more complicated, partly because oxygen, which is lost during flight in the high-temperature zone of the plasma jet, can be recovered at longer spray distances. As a result, the saturation magnetization of MZF coatings decreases and the coercivity increases with increased particle temperature or decreased particle velocity. 相似文献
54.
EFFECT OF STEPWISE CHANGE OF DRYING RATE ON MICROSTRUCTURE EVOLUTION IN POLYMER FILMS 总被引:2,自引:0,他引:2
Masato Yamamura Takatoshi Nishio Toshihisa Kajiwara Kitaro Adachi 《Drying Technology》2001,19(7):1397-1410
The effect of the drying rate of the solvent on microstructure evolution in thin films of immiscible polystyrene/polycarbonate blends was investigated by applying a stepwise change in air velocity. The polymer blend was dissolved in tetrahydrofuran and cast on a glass substrate to form a thin liquid film. The drying rate of the solvent was measured by a gravimetric technique, and the phase-separated structure in the film was observed by optical microscopy. The results indicated that cellular structures of droplet arrays were formed in the phases evolved primarily during the early stage of drying, and the droplets then coalesced in the intermediate stage to form bigger droplets. The size of the first evolved phase decreased with increasing time at a high drying rate, whereas larger droplets were obtained with longer high drying rate regimes. These results suggested that the droplets were induced by secondary phase separation which was strongly affected by the drying rate of the solvent. 相似文献
55.
56.
Masayuki Ohta Keitaro Kondo Masayuki Matsunaka Hiroyuki Miyamaru Isao Murata Toshiyuki Iida Kentaro Ochiai Chikara Konno 《Fusion Engineering and Design》2009,84(7-11):1446-1449
Integral benchmark experiments with DT neutrons are not always sufficient for nuclear data benchmarking in the MeV region, below 10 MeV. A neutron spectrum shifter, which will be placed between a sample and a DT neutron source, is effective to moderate DT neutrons incident to the sample. In order to estimate effects of the spectrum shifter, the ratio of the contribution of 14 MeV neutrons in the leakage neutron and gamma-ray spectra was calculated with MCNP-4C for an experimental configuration at FNS of JAEA, Japan. The calculations were carried out for a Li2TiO3 sample with a Be, D2O, or 7LiD spectrum shifter. It was found out that the Be shifter was superior to others and the Be shifter was effective to decrease the contribution of 14 MeV neutrons especially for secondary gamma-ray spectrum measurements. 相似文献
57.
Shinobu Hashimoto Kentaro Hattori Ayuka Nakahashi Yuji Iwamoto 《Materials Research Bulletin》2009,44(1):70-3888
Pure-phase LiAl5O8 was selected as an oxide ceramic red phosphor material without dopants (color centers) and was synthesized using a self-flux method. The LiAl5O8 was formed by heating a powder mixture consisting of γ-Al2O3:Li2SO4 = 1:2 (molar ratio) at over 1100 °C for 1 h. Photoluminescence (PL) properties for the synthesized LiAl5O8 were investigated. The maximum intensity of the excitation spectrum for the photoluminescent emission of LiAl5O8 synthesized was at 274 nm. The peak intensity of the emission spectrum was at a wavelength of 667 nm (red color). The intensity of the peak emission spectrum increased with the heating temperature, i.e., the maximum peak intensity of the red emission spectrum was detected for the LiAl5O8 synthesized by heating at 1500 °C for 1 h. 相似文献
58.
Shioiri S Ito S Sakurai K Yaguchi H 《Journal of the Optical Society of America. A, Optics, image science, and vision》2002,19(11):2169-2179
We measured the lowest velocity (velocity threshold) for discriminating motion direction in relative and uniform motion stimuli, varying the contrast and the spatial frequency of the stimulus gratings. The results showed significant differences in the effects of contrast and spatial frequency on the threshold, as well as on the absolute threshold level between the two motion conditions, except when the contrast was 1% or lower. Little effect of spatial frequency was found for uniform motion, whereas a bandpass property with a peak at approximately 5 cycles per degree was found for relative motion. It was also found that contrast had little effect on uniform motion, whereas the threshold decreased with increases in contrast up to 85% for relative motion. These differences cannot be attributed to possible differences in eye movements between the relative and the uniform motion conditions, because the spatial-frequency characteristics differed in the two conditions even when the presentation duration was short enough to prevent eye movements. The differences also cannot be attributed to detecting positional changes, because the velocity threshold was not determined by the total distance of the stimulus movements. These results suggest that there are two different motion pathways: one that specializes in relative motion and one that specializes in uniform or global motion. A simulation showed that the difference in the response functions of the two possible pathways accounts for the differences in the spatial-frequency and contrast dependency of the velocity threshold. 相似文献
59.
Achromobacter protease I (API), a lysine-specific serine protease, shows one order of magnitude higher activity than bovine trypsin, while its optimum pH is in the alkaline region at about pH 9. To improve the optimum pH range, mutant enzyme His 210 replaced by Ser(H210S), Ala (H210A), and Lys (H210K) were constructed. The optimum pH of H210S shifted from about pH 9 (wild-type enzyme) to about pH 7, retaining its high activity. The putative electrostatic interaction between His 210 and catalytic Asp 113 was elucidated by the optimum-pH shift of H210K and H210A. These results indicate that this unconserved His 210 in API, which plays a key role in generating the useful peptidase, broadened the optimum-pH range without decreasing lysylendo-peptidase activity. 相似文献
60.
Safwat Hassaballa Yasushi Sonoda Kentaro Tomita Young Kee Kim Kiichiro Uchino 《Journal of the Society for Information Display》2005,13(8):639-645
Abstract— Properties of a plasma‐display‐panel (PDP) like discharge were examined by emission and laser Thomson scattering (LTS) measurements. Emission measurements were performed using an intensified CCD camera. By varying several external parameters such as the amplitude of the input voltage, gas composition, and pressure, the influence of these parameters on the discharge behavior was studied. Results of emission measurements showed that they were in good agreement with similar emission measurements on real PDP cells. LTS measurements were performed for the striated PDP‐like discharge at a pressure of 100 Torr and the results showed clear modulations in both profiles of electron density and electron temperature. 相似文献