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排序方式: 共有1006条查询结果,搜索用时 15 毫秒
41.
Kyoko Hori Masahiro Fukuta Hirokazu Shimooka Shigemi Kohiki Toetsu Shishido Masaoki Oku Masanori Mitome Yoshio Bando 《Journal of Alloys and Compounds》2005,390(1-2):261-264
β-Ga2O3 nanocolumns straightened and crossed perpendicularly each other were deposited on MgO (1 0 0) substrate by vapor phase transport method. Growth of the nanocolumns was examined at steps of 1000, 1050, and 1200 °C in elevation of source-boat temperature. We have drawn out the substrate from deposition-tube at each source-boat temperatures of 1000, 1050, and 1200 °C. Scanning electron microscopy of the sample with source-boat temperature of 1200 °C demonstrated that the straightened and elongated nanocolumns are crossing perpendicularly each other. Typical lengths of the nanocolumns were in the range of several hundreds nanometers below 1050 °C, and those of 1200 °C were in the range of ten to fifteen hundreds nanometers. Diameters of the nanocolumns stayed in the range of few hundreds nanometers, notwithstanding variation of the source temperature. X-ray diffraction and transmission electron microscopy with energy dispersive X-ray spectroscopy revealed that the nanocolumns are monoclinic β-Ga2O3 crystal, and the (4 0 0) plane of β-Ga2O3 nanocolumns is parallel to the (1 0 0) plane of MgO substrate. 相似文献
42.
Izumi Satake John H. XinTu Tianming Aran HansuebsaiKenji Ando Tetsuya SatoKanji Kajiwara Seiji Ohsawa 《Progress in Organic Coatings》2011,72(3):528-540
This article compares color assessments of automotive exteriors at four locations in China, Thailand and Japan. This study employed painted panels of twelve colors, thirty sensory words and fifteen pairs of emotion variables. It also used reference figures of nine cars that included four styling categories, namely sedans, compacts, sport utility vehicles and sports cars. The results of like-dislike tests revealed that basic automotive exterior colors, such as black, white and red, were highly preferred across locations. However, geographical differences are apparent in the preference for some non-basic colors. To elucidate these geographical differences, a Chi-square test and principal component analysis were performed on the data on emotion variables. The results revealed both similarities and differences in color preferences among the four locations. Color preferences were similar in Hong Kong and Shanghai when simply evaluated by color samples. However, similar preferences for automotive exterior colors were observed in Hong Kong, Kyoto and Bangkok, but not in Shanghai. These results suggest that there is fluctuation in the emotion evoked by a color when the color is considered in the context of automotive exteriors. Therefore, this study indicates that automotive sales can be secured in the global marketplace by creating a single palette of exterior colors based on similar color preferences across countries. However, these results also indicate that preparing market-specific automotive-color line-ups can be an effective marketing strategy. 相似文献
43.
Izumi Taniguchi Shinya Nakajima Zhumabay Bakenov 《Chemical Engineering Communications》2013,200(10):1292-1301
A novel technique has been developed to directly produce fine ceramic powders from liquid solution via spray pyrolysis in a fluidized bed reactor (SPFBR). Using this technique the preparation of LiM0.15Mn1.85O4 (M = Mn, Co, Al, and Fe), which are the most promising cathode materials for lithium-ion batteries, has been carried out at a superficial velocity U0 of 0.71 m/s, a reactor temperature T of 800°C, and a static bed height Ls of 100 mm. The as-prepared powders were spherical nanostructured particles that comprised primary particles of a few tens of nanometers in size, and they exhibited a pure cubic spinel structure without any impurities in the XRD patterns. The chemical composition of as-prepared samples showed good agreement with the theoretical values that proved stoichiometric formulae of the compounds. The specific surface area of as-prepared LiM0.15Mn1.85O4 (M = Mn, Co, Al, and Fe) powders decreases with increasing the static bed height in each doping metal, while the crystallite size increases with the static bed height. As a result, the as-prepared powders showed larger crystallite size and smaller specific surface area than those prepared by conventional spray pyrolysis. 相似文献
44.
Dr. Masayuki Izumi Akihisa Otsuki Mika Nishihara Dr. Ryo Okamoto Prof. Dr. Yasuhiro Kajihara 《Chembiochem : a European journal of chemical biology》2014,15(17):2503-2507
As a basis for the development of an artificial carbohydrate‐binding lectin, we chemically synthesized a domain of siglec‐7, a well‐characterized sialic‐acid‐binding lectin. The full polypeptide (127 amino acids) was constructed by sequential native chemical ligation (NCL) of five peptide segments. Because of poor cysteine availability for NCL, cysteine residues were introduced at suitable ligation sites; these cysteine residues were alkylated in order to mimic native glutamine or asparagine residues, or converted to an alanine residue by desulfurization after NCL. After folding the full‐length polypeptide, the sialic‐acid‐binding activity of the synthetic siglec‐7 was clearly demonstrated by STD NMR and ELISA experiments. We succeeded in the synthesis of siglec‐7 by installing three extra cysteine residues with side‐chain modifications and found that these modifications did not affect the binding activity. 相似文献
45.
46.
Cationic chitosan (CT) and anionic dextran sulfate (Dex) were layer-by-layer (LbL) assembled from aqueous solutions containing
1 M NaCl on a quartz crystal microbalance (QCM) substrate, and the original films ((CT-Dex)3-CT)) were end-capped with LbL assembly from CT solutions containing 1 M NaCl and Dex solutions without NaCl. The enzymatic
degradation of films by chitosanase was quantitatively analyzed by QCM in terms of numbers of end-capping steps. The degradation
of films end-capped with (Dex-CT)3 was considerably prolonged when compared to those end-capped with other end-capping steps. A mechanism for the prolonged
degradation was proposed by quantitative QCM data and zeta potential results. 相似文献
47.
Tetsuya OGAWA Hideki ISHIDA Nami MATSUDA Ayuko FUJIU Akiko MATSUDA Kyoko ITO Yoshitaka ANDO Kosaku NITTA 《Hemodialysis international. International Symposium on Home Hemodialysis》2009,13(3):301-306
Vascular calcification is associated with a poor prognosis in dialysis patients. It can be assessed with computed tomography but simple inoffice techniques may provide useful information. We compared the results obtained with a simple noninvasive technique with those obtained using multidetector computed tomography for aortic arch calcification volume (AoACV) in chronic hemodialysis (HD) patients. The enrolled study subjects were 63 (32 men and 31 women) maintenance HD patients. Calcification of the aortic arch was semiquantitatively estimated with a AoAC score (AoACS) on plain chest radiology. The AoACV was increased, with a mean value of 6.6 ranging from 0% to 36.5%. The coefficient of intraobserver variation was less than 2.5%. Aortic arch calcification score was highly correlated with AoACV (r=0.635, P<0.001). Multiple regression analysis showed age (F value=12.62, P<0.001) and pulse pressure (F value=4.54, P=0.037) to be significant independent determinants of AoACS. In conclusion, a simple measurement of AoACS may be useful for inoffice imaging to choose a therapeutic regimen in HD patients. 相似文献
48.
The goal of this paper is to augment the ordinal temporal-difference type (TD-type) reinforcement learning model in order to detect the most suitable learning model of the human decision-making process in financial investment tasks. The simplicity and robustness of the TD-type learning model is fascinating. However, the available evidence and our observation suggest the necessity of introducing the nonlinear effect in learning and the possibility that additional factors might play important roles in the investment decision-making process. To extend the ordinal TD-type learning model, we adopt a three-layered perceptron as the basis function and the hierarchical Bayesian method to calibrate the parameter values. The result of the predictive test suggests that the augmented TD-type learning model constructed in this paper can evade the overfitting and can predict people's investment behavior well as compared to other familiar learning models. 相似文献
49.
50.
Katsunori Takeda Tetsuo Hattori Tetsuya Izumi Hiromichi Kawano Shinichi Masuda 《Artificial Life and Robotics》2010,15(4):421-424
Recently, remote monitoring camera systems have been widely used for security. In such systems, one important function is
that the system automatically detects any change in the scenes from the monitoring cameras. In wireless remote monitoring
camera systems, the images of the scenes are generally transmitted as compressed data (e.g., JPEG file), because of the capacity
of the wireless channel. This article shows the automated detection of the change point in time-series data of compressed
JPEG file quantity (Kbytes) from the monitoring camera by applying the sequential probabilistic ratio test (SPRT) and the
Chow test, which is well known as a standard method for detecting structural change in time-series data. 相似文献