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991.
992.
Dong Liang Shun'ichi Kaneko Manabu Hashimoto Kenji Iwata Xinyue Zhao Yutaka Satoh 《International Journal of Optomechatronics》2014,8(1):14-29
In this study, a spatial-dependent background model for detecting objects is used in severe imaging conditions. It is robust in the cases of sudden illumination fluctuation and burst motion background. More importantly, it is quite sensitive under the cases of underexposure, low-illumination, and narrow dynamic range, all of which are very common phenomenon using a surveillance camera. The background model maintains statistical models in the form of multiple pixel pairs with few parameters. Experiments using several challenging datasets (Heavy Fog, PETS-2001, AIST-INDOOR, and a real surveillance application) confirm the robust performance in various imaging conditions. 相似文献
993.
We established a method to simultaneously determine RRR- and SRR-α-tocopherol (α-Toc) and their quinones in biological samples by chiral-phase high-performance liquid chromatography (HPLC).
α-Toc had a shorter retention time than α-tocopherylquinones (α-TQ), and 2-ambo-α-Toc was completely separated into two peaks; the first peak was RRR-α-Toc and the second SRR-isomer by chiral HPLC connected Chiralcel OD-H column and Sumichiral OA4100 column. In contrast, of the two peaks of α-TQ,
the first was the SRR-isomer. We also investigated differences in the distribution of RRR- and SRR-α-TQ in rat tissues after oral administration of 2-ambo-α-Toc by the above HPLC method. Rats deficient in vitamin E were divided into two groups, control and experimental, and tissues
were collected at 3, 6, and 24 h after oral 2-ambo-α-Toc administration. The concentrations of RRR- and SRR-α-Toc and their quinones in plasma and each tissue were determined. The concentration of SRR-α-TQ in plasma and adrenal glands was not significantly different from RRR-α-TQ. However, the concentration of SRR-α-TQ in liver up to 6 h after oral administration was higher than that of RRR-α-TQ, and SRR- and RRR-α-TQ levels were similar at 24 h after oral administration. Therefore, we may assume that the formation of α-TQ in vivo was not different between RRR- and SRR-isomer and that it was not affected by the presence of α-Toc stereoisomers. 相似文献
994.
Norimasa Shiomi W. X. Cai A. Muraoka K. Kaneko T. Setoguchi 《Journal of Mechanical Science and Technology》2001,15(12):1860-1868
An experimental investigation was carried out to clarify unsteady flow fields with rotating stall cell, especially behavior
of stall cell, in a high specific-speed diagonal flow fan. As its specific-speed is very high for a diagonal flow fan, its
pressure-flow rate curve tends to indicate unstable characteristics caused by rotating stall similar to axial flow fan. Although
for an axial flow fan many researchers have investigated such the flow field, for a diagonal flow fan little study has been
done. In this study, velocity fields at rotor inlet in a high specific-speed diagonal flow fan were measured by use of a single
slant hot-wire probe. These data were processed by using the ““Double Phase-Locked Averaging“ (DPLA) technique, i. e. phases
of both the rotor blade and the stall cell were taken into account. The behaviors of stall cell at rotor inlet were visualized
for the meridional, tangential and radial velocity. 相似文献
995.
The proportion of geometrical hydroperoxide isomers generated by aerobic oxidation of methyl linoleate (18∶2 Me) in either
aqueous emulsion consisting of Tris-HCl buffer (pH 7.4) or in a homogeneous dichloromethane solution was determined to understand
the mechanism of lipid oxidation in different reaction systems. Four geometrical isomers were generated after oxidation of
18∶2 Me in dichloromethane: methyl 13-hydroperoxy-cis-9,trans-11-octadecadienoate, methyl 13-hydroperoxy-trans-9,trans-11-octadecadienoate, methyl 9-hydroperoxy-trans-10,cis-12-octadecadienoate, and methyl 9-hydroperoxy-trans-10,trans-12-octadecadienoate in the ratios of 1∶4∶1∶4, respectively. The ratios between each isomer did not change until the peroxide
value (PV) increased to 58 meq/kg. Oxidation of 18∶2 Me in aqueous emulsion yielded the same geometrical isomers of hydroperoxide.
However, the ratios were different: 3∶2∶3∶2 until the PV increased to 110 meq/kg. Predominant (60%) formation of trans,trans hydroperoxide isomers was obtained in the oxidation of a mixture of 18∶2 Me and methyl laurate (12∶0 Me). These results are
interpreted to reflect the importance of the concentration of hydrogen atom-donating equivalents to the kinetic preference
for different products. The high effective concentration of hydrogen donors in the oxidation of 18∶2 Me in emulsions favored
the formation of the less stable cis,trans isomers. The lower concentration of hydrogen donor in the dichloromethane solution effectively slowed hydrogen donation and
led to the strong preference for the more stable trans,trans isomers. This interpretation was further tested by preparing emulsions of 18∶2 Me and 12∶0 Me to dilute concentration of
hydrogen-donating species using the nonhydrogen-donating 12∶0 Me. Consistent with the proposed hypothesis, the proportion
of trans,trans isomers increased as a result of 12∶0 Me addition. 相似文献
996.
Yoshitaka Nara Naoki Hiroyoshi Tetsuro Yoneda Katsuhiko Kaneko 《International Journal of Rock Mechanics and Mining Sciences》2010,47(4):640-646
Effects of relative humidity and temperature on subcritical crack growth in igneous rock have been investigated experimentally on samples of Kumamoto andesite and Oshima granite. Stress intensity factors and crack velocities were measured using the double-torsion technique, and all experiments were conducted in moist air. Our results show that in experiments conducted under the same relative humidity, crack velocity increased with increasing temperature, in agreement with previous studies. Our results also show that, in experiments conducted at the same temperature, crack velocity increased dramatically with increasing relative humidity. A three- to fourfold increase in relative humidity resulted in an increase in crack velocity of between one and four orders of magnitude. Such an increase is larger than that predicted by classical stress corrosion theory. It is suggested that capillary condensation of water vapour close to crack tips of small aperture influences the rate of crack growth. It is concluded that relative humidity needs to be controlled to avoid time-dependent weakening and extend the lifetime of structures in a rock mass. 相似文献
997.
Junji Nagao Shigeru Matsuo Shotaro Suetsugu Toshiaki Setoguchi Heuy Dong Kim 《International Journal of Hydrogen Energy》2013
A critical nozzle has been used to measure a mass flow rate of gas. It is well known that the coefficient of discharge of the flow in a critical nozzle is a single function of Reynolds number. The purpose of the present study is to investigate the effect of equation of state (EOS) on the coefficient of discharge and thermodynamics properties through the critical nozzle by using H2 with the help of a CFD method. In computations of the flow field including the stagnation point upstream of the nozzle, the Redlich–Kwong, Lee–Kesler and Peng–Robinson equations of state were employed to take account of real gas effects. As a result of the present computations, coefficients of discharge using the Redlich–Kwong and Lee–Kesler EOS were in good agreement with experimental results in the range of high Reynolds number and the coefficient of discharge decreased with an increase of Reynolds number in the range of 1.0 × 105 < Re < 2.8 × 106. 相似文献
998.
T. Miyazaki K. Yamaoka T. Kaneko J.P. Gong 《Science and Technology of Advanced Materials》2013,14(4):201-210
A water-swollen hydrogel with a molecularly-ordered structure was prepared by copolymerizing acrylic acid and acrylic monomer containing hydrophobic long alkyl or mesogenic moiety. The gels with a long alkyl side chain formed the crystalline structure and undergo the reversible order–disorder transition with change in temperature or solvent composition which accompanied a dramatic change in Young’s modulus. These gels exhibited such chemomechanical behaviors as the shape memory and the rotational motility on the water surface. On the other hand, the gels with the mesogenic side chain formed the liquid crystalline structure with polymorphism in water, and mesophase diagram was established by changing copolymer composition and water content. Mechanism of these structural and chemomechanical behaviors has been explained in terms of order–disorder transition. 相似文献
999.
Kiyohiko Igarashi Satoshi Kaneko Motomitsu Kitaoka Masahiro Samejima 《Journal of Applied Glycoscience》2020,67(2):51
Cellobiose dehydrogenase (CDH) is a flavocytochrome catalyzing oxidation of the reducing end of cellobiose and cellooligosaccharides, and has a key role in the degradation of cellulosic biomass by filamentous fungi. Here, we use a lineup of glucose/xylose-mixed β-1,4-linked disaccharides and trisaccharides, enzymatically synthesized by means of the reverse reaction of cellobiose phosphorylase and cellodextrin phosphorylase, to investigate the substrate recognition of CDH. We found that CDH utilizes β-D-xylopyranosyl-(1→4)-D-glucopyranose (Xyl-Glc) as an electron donor with similar K m and k cat values to cellobiose. β-D-Glucopyranosyl-(1→4)-D-xylopyranose (Glc-Xyl) shows a higher K m value, while xylobiose does not serve as a substrate. Trisaccharides show similar behavior; i.e., trisaccharides with cellobiose and Xyl-Glc units at the reducing end show similar kinetics, while the enzyme was less active towards those with Glc-Xyl, and inactive towards those with xylobiose. We also use docking simulation to evaluate substrate recognition of the disaccharides, and we discuss possible molecular mechanisms of substrate recognition by CDH. 相似文献
1000.
Toshiaki Yamaguchi Kevin V. GallowayJieon Yoon Nigel M. Sammes 《Journal of power sources》2011,196(5):2627-2630
We report the long-term stability of a microtubular solid oxide fuel cell (SOFC) operable at ∼500 °C. The SOFC consists of NiO-Gd doped ceria (GDC) as the anode as well as the tubular support, GDC as an electrolyte and La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF)-GDC as the cathode. A single tubular cell with a diameter of approximately 1.8 mm and an effective electrode length of approximately 20 mm generated 150 mW cm−2 and 340 mW cm−2 at 500 °C and 550 °C, respectively, under the operation conditions of 0.7 V and humidified H2 fuel flow. The cell exhibited good stability with a degradation rate of 0.25%/100 h under operation conditions of 200 mA and 0.75 V. 相似文献