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排序方式: 共有1064条查询结果,搜索用时 15 毫秒
991.
Kiichi Suzuki Masato Kato Takeo Sunaoshi Hiroki Uno Ursula Carvajal-Nunez Andrew T. Nelson Kenneth J. McClellan 《Journal of the American Ceramic Society》2019,102(4):1994-2008
The thermal and mechanical properties of cerium dioxide (CeO2) were assessed using a range of experimental techniques. The oxygen potential of CeO2 was measured by the thermogravimetric technique, and a numerical fit for the oxygen potential of CeO2 is derived based on defect chemistry. Mechanical properties of CeO2 were obtained using sound velocity measurement, resonant ultrasound spectroscopy and nanoindentation. The obtained mechanical properties of CeO2 are then used to evaluate the Debye temperature and Grüneisen constant. The heat capacity and thermal conductivity of CeO2 were also calculated using the Debye temperature and the Grüneisen constant. Finally, the thermal conductivity was calculated based upon laser flash analysis measurements performed on pellets fabricated using a range of feedstock purities to resolve discrepancies in the existing literature. 相似文献
992.
Yuji Nobuta Yuji Yamauchi Tomoaki Hino Satoshi Akamaru Yuji Hatano Masao Matsuyama Satoshi Suzuki Masato Akiba 《Fusion Engineering and Design》2012,87(7-8):1070-1073
Co-deposited carbon film with different deuterium concentration, D/C, were exposed to tritium gas at the temperature of 423 K, and then the atomic ratio of absorbed tritium to carbon, T/C, was evaluated. The obtained data were discussed with crystal structure of the carbon film. The T/C increased with decreasing D/C of carbon film. The carbon film with low D/C had more defective structure. The reduction of D/C by the heating before tritium exposure led to the increase of absorption amount. These results suggest that carbon film with more defective structure and low D/C film could absorb large amount of tritium. The hydrogen isotope concentration in the present experiment was saturated below the orders of 10?4, which was 3–4 orders of magnitude smaller than that of co-deposited carbon film with hydrogen isotope. 相似文献
993.
Shigeharu Tamura Masato Yasumoto Nagao Kamijo Akihisa Takeuchi Yasuko Terada 《Vacuum》2010,84(12):1457-1459
The Fresnel zone plate (FZP) is a type of lens for focusing X-rays. We have fabricated a kinoform style FZP with a 30-step structure composed of concentric multilayer of alternating Cu layer, Al layer, and 28 composite material (Cu, Al) layers. The multilayer was deposited using a magnetron sputtering apparatus with two DC-sputtering guns. The focusing characteristics were evaluated at the synchrotron radiation beamline of SPring-8, and the focused beam size measured by knife-edge scanning was 0.8 μm at 40 keV. The peak diffraction efficiencies measured using ion chambers for 1st- and 2nd-order diffraction were 42% and 12% at 40 keV and 20 keV, respectively. High-order X-ray diffraction was also examined using the data obtained from a CCD camera. 相似文献
994.
Shinohara N Kajiwara T Ohnishi M Kodama K Yanagisawa Y 《Environmental science & technology》2008,42(12):4472-4477
A coin-sized passive emission colorimetric sensor (PECS) based on an enzymatic reaction and a portable reflectance photometry device were developed to determine the emission rates of formaldehyde from building materials and other materials found indoors in only 30 minutes on-site. The color change of the PECS linearly correlated to the concentration of formaldehyde aqueous solutions up to 28 microg/mL. The correlation between the emission rates measured by using the PECS and those measured by using a desiccator method or by using a chamber method was fitted with a linear function and a power function, and the determination coefficients were more than 0.98. The reproducible results indicate that the emission rates could be obtained with the correlation equations from the data measured by using the PECS and the portable reflectance photometry device. Limits of detection (LODs) were 0.051 mg/L for the desiccator method and 3.1 microg/m2/h for the chamber method. Thus, it was confirmed that the emission rates of formaldehyde from the building materials classified as F four-star (< 0.3 mg/L (desiccator method) or < 5.0 microg/m2/h (chamber method)), based on Japanese Industrial Standards (JIS), could be measured with the PECS. The measurement with PECS was confirmed to be precise (RSD < 10%). Other chemicals emitted from indoor materials, such as methanol, ethanol, acetone, toluene, and xylene, interfered little with the measurement of formaldehyde emission rates by using the PECS. 相似文献
995.
Yoshitaka Maeda Hiroyasu Shimoji Takashi Todaka Masato Enokizono 《IEEJ Transactions on Electrical and Electronic Engineering》2008,3(2):222-228
In the development of high‐efficiency actuators, high‐magnetic flux density conditions are applied to achieve higher torque, lower weight and smaller size. It is therefore very important to understand the magnetic properties under high‐magnetic flux conditions in the electrical steel sheets. However, it is very difficult to measure the two‐dimensional vector magnetic properties under high‐flux density conditions due to nonlinearity and anisotropy of the magnetic materials. The measured magnetic power loss under clockwise rotating fields differs from that of the counter‐clockwise direction, and the value in counter‐clockwise rotating fields sometimes becomes negative. It can be considered that angle errors of H‐coils and B‐coils are the main causes of the measurement errors. In this paper, the angle errors of the double B‐coil (search coils) and the double H‐coil (cross‐type H‐coil) are evaluated with a projector‐type magnifying scope and a calibration device. We have compensated the measured magnetic field vector components caused by the angle errors and made clear their influence on the two‐dimensional vector magnetic property measurements. Furthermore, we proposed a method to cancel out small angle errors that remained in the saturated region. Copyright © 2008 Institute of Electrical Engineers of Japan. Published by John Wiley & Sons, Inc. 相似文献
996.
Toshihiko Hoshide Masato Hirano 《Journal of Materials Engineering and Performance》2010,19(4):562-567
The durability of coated materials with high performance should be adequately evaluated prior to their application. This study
aims at establishing a procedure to estimate the durability of such materials. In this study, a borosilicate glass was coated
with ceramic films by a radio-frequency (RF) magnetron sputtering method, and mechanical properties of materials coated with
single ceramic materials, alumina (Al2O3), silicon carbide (SiC), or titanium nitride (TiN), were investigated. Roughness and hardness were measured as surface characteristics
of coated glass. The strength of coated glass was evaluated under three-point bending mode. It was found that the strength
properties were improved by coating ceramic materials on glass. As for the strength properties, TiN-coated glass was superior
to Al2O3- or SiC-coated glass, although the surface of TiN-coated glass was rougher compared with that of Al2O3- or SiC-coated glass. A new procedure to estimate the strength of coated materials was proposed by incorporating relative
hardness and roughness variations with sputtering time. The strength in experiments was adequately estimated by using the
proposed procedure. 相似文献
997.
Sook Wai Phang Masato Tadokoro Jiro Watanabe Noriyuki Kuramoto 《Synthetic Metals》2008,158(6):251-258
As nanomaterial possessing moderate conductivity, magnetic and dielectric property, novel hexanoic acid (HA)-doped polyaniline (PAni) nanocomposites containing TiO2 nanoparticles (dielectric filler) and carbon nanotubes, CNTs (magnetic fillers such as single-walled carbon nanotube, SWNT and multi-walled carbon nanotube, MWNT) were prepared by template free method. The PAni were characterized by UV, FTIR, X-ray diffraction (XRD), thermogravimetric (TGA) and scanning electron microscopy (SEM) analyses. Conductivity, magnetization, dielectric and microwave absorption properties of PAni were also investigated. The resulted nanorods/tubes as shown in SEM images clearly show that polymerization is proceeded in micelle/water interface through elongation. During template free method, TiO2 and CNT exist in the center of Ani/HA micelle. The SEM images show that some of the CNT enwrapped with PAni layer indicate CNT are just packed underneath the PAni and never attacked by PAni. PAni/HA/TiO2/SWNT with 20% of SWNT exhibits the best microwave absorption property (99.2% absorption) with reflection loss of −21.7 dB at 6 GHz due to its moderate conductivity (1.27 S/cm), magnetization (Ms = 1.01 emu/g), highest tan δ and heterogeneity. 相似文献
998.
Production of gamma-aminobutyric acid from alcohol distillery lees by Lactobacillus brevis IFO-12005
Lactobacillus brevis IFO-12005 showed good growth in rice shochu distillery lees (kome shochu kasu). Almost all of the free glutamic acid (10.50 mM) in shochu kasu was converted to gamma-amino-butyric acid (GABA) within 2 d of stationary culture at 30 degrees C. The amount of GABA in the kome shochu kasu medium finally reached 10.18 mM. After centrifugation of the broth culture, the supernatant fraction was treated with a flocculation agent to form a clear solution, then passed through a column containing a synthetic adsorbents, SP-207 to remove the yellow pigment and flavors which are unnecessary from a sensory perspective. An economical and simple production process for GABA was established. 相似文献
999.
Kawahara T Shimokawa I Tomita M Hirano T Shindo H 《Microscopy research and technique》2002,59(4):306-312
We previously demonstrated that caloric restriction (CR) reduced the prevalence of osteonecrosis in caput femoris of spontaneously hypertensive rats (SHR), a model of human Perthes' disease. The effects of CR on the development and pathology in the proximal femoral growth plate (GP) and adjacent structures in SHR were investigated by morphometric and computer-assisted image analyses. From 6 weeks of age, the food intake of SHR was restricted to 65% of the mean intake of ad libitum fed control SHR (SHR-AL). Wistar Kyoto rats (WKY), from which the SHR strain was isolated, fed ad libitum were also included as controls. CR reduced prevalence of chondromucinous degeneration and dysarray of cartilage cell columns in the GP, becoming prevalent between 10 and 20 weeks in the SHR-AL group, attaining the same levels of the WKY group. Thicknesses of non-calcifying cell columns in the GP were greater in the SHR-AL than WKY group; CR slightly reduced the thickness, but incompletely. Thicknesses of calcifying cell columns did not significantly differ among the three groups. CR decreased volume density and mean thicknesses of the trabecular bone in areas adjacent to GPs, and was greater in the SHR-AL than the WKY group. The present morphologic analysis suggested that CR ameliorates dysplastic changes of trabecular bones in areas adjacent to the GP, rather than modulating the ossification process in the GP. The CR paradigm might give insight into the pathogenesis of, and a therapeutic strategy for, human Perthes' disease. 相似文献
1000.
FL cells infected with vaccinia virus or its recombinant carrying the gag gene of human immunodeficiency virus type 1 (HIV-1) were examined by ultra-high-resolution scanning electron microscopy. Virions, whether located extracellularly or intracellularly, had a brick-shaped or watermelon appearance as a whole. Extracellular virions observed on the surface of infected cells had variable surface ultrastructures depending on the manner in which particular virions were wrapped in cell membranes. Most of the intracellular naked virions adherent to the inner face of cell surface membranes clearly exhibited ridgy, rod-shaped or globular surface structures on their surface. HIV-like particles with a diameter of about 100 nm and virions of vaccinia virus were both observed distinctly on the surface of FL cells infected with the recombinant virus. 相似文献