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991.
Kyoichi Kinoshita Osamu NakatsukaShinichi Yoda Shigeaki Zaima 《Thin solid films》2012,520(8):3279-3282
Compositionally uniform Si0.5Ge0.5 bulk crystals were grown by the traveling liquidus-zone method which we developed for alloy crystal growth. Grown crystals were characterized as substrates for compressive-strained Ge thin films for high mobility p-channels of complementary metal oxide semiconductor transistors. Compositional uniformity was excellent and crystallinity was also excellent for 10 mm diameter crystals. However, crystallinity was degraded for 30 mm diameter crystals although compositional uniformity was excellent. Transmission electron microscope (TEM) observation showed high dislocation density at the interface between a Si seed and a grown crystal due to lattice mismatch. However, the dislocation density decreased as crystal growth proceeded. High quality 30 mm diameter crystals will be grown when the single crystal length is extended judging from TEM results. In this paper, we report on the growth and characterization of Si0.5Ge0.5 crystals as substrates for strained Ge thin films. 相似文献
992.
BaTiO3 nano-coated SiO2 (BaTiO3–SiO2) hybrid particles were prepared by liquid phase deposition and sol–gel process. The obtained BaTiO3–SiO2 hybrid particles have relatively high surface area (20 m2 g−1) at 600 °C annealing temperature. Ni component was impregnated to the obtained BaTiO3–SiO2 hybrid particles, and the obtained catalyst was used for the methane steam reforming process to consider the effect of the surface area on the catalytic activity. The catalytic activity of the Ni/BaTiO3–SiO2 catalyst was approximately three times as large as that of the reported Ni/BaTiO3 catalyst, even in the lower process temperature. However, the limitation temperature for methane steam reforming process of this hybrid material was 600 °C, because of the diffusion of the Ba component. 相似文献
993.
994.
Analysis of coumarin and its glycosidically bound precursor in Japanese green tea having sweet-herbaceous odour 总被引:2,自引:0,他引:2
Ziyin Yang Tomomi Kinoshita Aya Tanida Hironori Sayama Akio Morita Naoharu Watanabe 《Food chemistry》2009
Coumarin is a natural product well-known for its pleasant sweet-herbaceous and cherry flower-like odour. Despite coumarin being widely found in the plant kingdom, its occurrence in tea leaves is very poorly characterised. In this work, green tea made from the cultivars “Shizu-7132”, “Koushun” and “Tsuyuhikari” were found to have sweet-herbaceous odour. Application of the stable isotope dilution assay for the quantification of coumarin revealed that its levels in these Japanese green tea products ranged from 0.26 to 0.88 μg/g of green tea product, whereas concentrations were generally below 0.2 μg/g in common green tea products. In contrast to the leaf, the stem part contained much less coumarin. During the manufacturing process of the tea (Shizu-7132), the steaming time and drying temperature influenced the content of coumarin in the final product. Due to hydrolysis of glycosidically bound coumarin precursors, in fresh tea leaves most coumarin occurred in its free form. Tea leaves also contained small amounts of bound coumarin precursors, such as primeveroside. 相似文献
995.
Akio Yamamoto Kuniharu Kinoshita Tomohiro Endo 《Journal of Nuclear Science and Technology》2017,54(4):459-471
In this paper, we estimate prediction errors owing to approximations in calculation models (modeling approximation error) using the data assimilation method. Correlations between the modeling approximation error and neutronics parameters obtained through calculations are evaluated in test configurations and then the evaluated correlations are used to predict the modeling approximation errors in design configuration. Formulae to estimate the modeling approximation error using the correlations are derived based on the minimum variance approach and the physical interpretation of the formulae is discussed through simple cases. The proposed method is applied in 2 × 2 and 3 × 3 fuel assembly geometries using specifications of the KAIST benchmark problem. The correlation between the modeling approximation error and parameters (neutron leakage in each fuel assembly) is estimated in 2 × 2 fuel assemblies and then the modeling approximation error in 3 × 3 fuel assemblies is predicted using the correlation. The calculation results not only indicate feasibility of the present method, but also suggest a need for further investigation on the assumptions used in the present study, i.e. applicability and robustness of the correlation among different geometries. 相似文献
996.
Ephantus Nguma Yuki Tominaga Shinji Yamashita Yurika Otoki Ayaka Yamamoto Kiyotaka Nakagawa Teruo Miyazawa Mikio Kinoshita 《Lipids》2021,56(2):167-180
Ethanolamine plasmalogen (PlsEtn), a sub-class of ethanolamine glycerophospholipids (EtnGpl), is a universal phospholipid in mammalian membranes. Several researchers are interested in the relationship between colon carcinogenesis and colon PlsEtn levels. Here, we evaluated the functional role of dietary purified EtnGpl from the ascidian muscle (87.3 mol% PlsEtn in EtnGpl) and porcine liver (7.2 mol% PlsEtn in EtnGpl) in 1,2-dimethylhydrazine (DMH)-induced aberrant crypt foci (ACF) in vivo, and elucidated the possible underlying mechanisms behind it. Dietary EtnGpl-suppressed DMH-induced aberrant crypt with one foci (AC1) and total ACF formation (P < 0.05). ACF suppression by dietary ascidian muscle EtnGpl was higher compared with dietary porcine liver EtnGpl. Additionally, dietary EtnGpl decreased DMH-induced oxidative damage, overproduction of TNF-α, and expression of apoptosis-related proteins in the colon mucosa. The effect of dietary ascidian muscle EtnGpl showed superiority compared with dietary porcine liver EtnGpl. Our results demonstrate the mechanisms by which dietary PlsEtn suppress ACF formation and apoptosis. Dietary PlsEtn attained this suppression by reducing colon inflammation and oxidative stress hence a reduction in DMH-induced intestinal impairment. These findings provide new insights about the functional role of dietary PlsEtn during colon carcinogenesis. 相似文献
997.
D. Laux D. Baron G. Despaux A.I. Kellerbauer M. Kinoshita 《Journal of Nuclear Materials》2012,420(1-3):94-100
We report the measurement of elastic constants of non-irradiated UO2, SIMFUEL (simulated spent fuel: UO2 with several additives which aim to simulate the effect of burnup) and irradiated fuel by focused acoustic microscopy. To qualify the technique a parametric study was conducted by performing measurements on depleted uranium oxide (with various volume fraction of porosity, Oxygen-to-metal ratios, grain sizes) and SIMFUEL and by comparing them with previous works presented in the literature. Our approach was in line with existing literature for each parameter studied. It was shown that the main parameters influencing the elastic moduli are the amount of fission products in solution (related to burnup) and the pore density and shape, the influence of which has been evaluated. The other parameters (irradiation defects, oxygen-to-metal ratio and grain sizes) mainly increase the attenuation of the ultrasonic wave but do not change the wave velocity, which is used in the proposed method to evaluate Young’s modulus. Measurements on irradiated fuel (HBRP and N118) were then performed. A global decrease of 25% of the elastic modulus between 0 and 100 GWd/tM was observed. This observation is compared to results obtained with measurements conducted at ITU by Knoop indentation techniques. 相似文献
998.
Kazuhiko Kinoshita Makoto Takano Young-Woo Lee Sanwei Sun Toshio Tonouchi Yoonhee Kim Teh-Sheng Huang 《Journal of Network and Systems Management》2014,22(3):509-516
This paper presents a report on APNOMS 2013, which was held September 25–27, 2013 in the International Conference Center, Hiroshima, Japan. The theme of APNOMS 2013 was “Integrated Management of Network Virtualization”. 相似文献
999.
Keita O. Ito Hongtao Sui Hidetoshi Hakozaki Hiroshi Kinoshita Ryosuke O. Suzuki 《Journal of Electronic Materials》2014,43(6):2086-2093
A water lens is employed to concentrate sunlight on the surface of a thermoelectric module in order to heat it. This water lens can change its shape flexibly and is adjustable to solar altitudes. The lens shape and light path were simulated for the cases when the light is incident at an angle to the water surface, parallel to the central axis of the half-cylindrical water lens, and when the light is focused on a plate. A condensing ratio larger than 70 is achieved when the incident light is closer to the normal of the water surface and if the optimal lens shape is maintained. 相似文献
1000.
Tamotsu Tsukahara Yoshikaszu Matsuda Hisao Haniu 《International journal of molecular sciences》2015,16(1):40-48
Carbon nanotubes (CNTs) are promising nanomaterials having unique physical and chemical properties, with applications in a variety of fields. In this review, we briefly summarize the intrinsic properties of highly purified multi-walled CNTs (MWCNTs, HTT2800) and their potential hazardous effects on intracellular and extracellular pathways, which alter cellular signaling and impact major cell functions such as differentiation, reactive oxygen species (ROS) production, apoptosis, and autophagy. A recent study suggested that the induction of autophagy by CNTs causes nanotoxicity. Autophagy was recently recognized as a critical cell death pathway, and autophagosome accumulation has been found to be associated with exposure to CNTs. Although autophagy is considered as a cytoprotective process, it is often observed in association with cell death, and the relationship between autophagy and cell death remains unclear. Our recent study suggests that the levels of autophagy-related genes (LC3B) and autophagosome formation are clearly up-regulated, along with an increase in numbers of autophagosome vacuoles. This review highlights the importance of autophagy as an emerging mechanism of CNT toxicity. 相似文献