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101.
Masaaki Matsui Kazuhito Ishikawa Hiroshi Matsuoka Masao Doyama Kusuo Nishiyama Kanetada Nagamine 《Journal of Nuclear Materials》1990,170(3):211-216
Magnetic susceptibility measurement and the zero-field muon-spin-relaxation experiment have been made for the YBa2(Cu1−xFex)3Oy system. The susceptibility has been measured in the field strong enough for the magnetic flux to penetrate the superconductor and the resultant temperature dependence has demonstrated the field cooled effect and a cusp at low temperatures below Tc. The cusp has been observed when the high field has been applied. The dynamical depolarization rate of the muon obtained by the muon-spin-relaxation experiment has shown the maximum at the same temperature as the cusp. The results suggest that the spin glass freezing of localized magnetic moment takes place at the temperature of the cusp, which is consistent with the previous Mössbauer effect experiments. The magnetic phase diagram for the system has been obtained. 相似文献
102.
The resolution of a series of racemic 1-alkyl-3-trityl-rac-glycerols and 1-alkyl-2-benzyl-rac-glycerols into their enantiomers by high-performance liquid chromatography (HPLC) was investigated. Of the racemic glycerol
derivatives studied, only three (1,2-0-isopropylidene-rac-glycerol, 1,2-0-isopropylidene-3-benzyl-rac-glycerol and 1-hexadecyl-2-benzyl-rac-glycerol) could be resolved into their enantiomers. The compounds were resolved on a silica (10 μm) column coated with cellulose
tribenzoate and eluted isocratically with hexane/isopropanol as mobile phase. The effects of mobile phase composition, column
temperature and flow rate on the resolution of enantiomeric pairs were investigated. Also, the effect of substituents,i.e., trityl, benzyl, hydroxyl or alkyl, on the resolution of the alkyl glycerol ethers by HPLC was evaluated.
Presented in part at the AOCS 80th Annual Meeting, Cincinnati, Ohio, May 1989. Mention of brand or firm names does not constitute
an endorsement by the U.S. Department of Agriculture over others of a similar nature not mentioned. 相似文献
103.
Kazuhito Nishikawa Yuji HiroseOsamu Urakawa Keiichiro Adachi Akira HatanoYuji Aoki 《Polymer》2002,43(4):1483-1490
We investigated ultrasonic attenuation, dynamic Young's modulus, Izod impact strength, and dielectric relaxation of acrylonitrile-butadiene-styrene composite polymers (ABS) in which styrene-co-butadiene rubber particles are dispersed in styrene-co-acrylonitrile random copolymer. High ultrasonic attenuation was observed around 240 K and the intensity of attenuation increased with increasing rubber content. Temperature dependence curves of dielectric loss in the frequency range from 12 Hz to 200 kHz and temperature range from 80 to 420 K exhibited four relaxation processes designated as the α, β′, β, and γ. From the relaxation map produced for the mechanical and dielectric relaxations, the ultrasonic absorption was attributed to the β and β′ processes. It was deduced that inter-grain thermoelastic process, also contribute to the ultrasonic attenuation. Correlation was found between the ultrasonic absorption and the Izod impact strength indicating that the high impact strength of ABS is partly due to the effective absorption of impact energy through those relaxation processes. 相似文献
104.
105.
Kenta Yonekura Chyon Hae Kim Kazuhiro Nakadai Hiroshi Tsujino Kazuhito Yokoi 《Advanced Robotics》2013,27(14):901-912
Effective rhythm expression (ERE) from a robot to a human performing a multi-modal physical-cooperation (MMPC) task was accomplished. During MMPC, the participant and the robot can exchange various rhythms between themselves. To accomplish ERE, it is important to appropriately select the modalities in which the robot expresses its desired rhythm. Accordingly, a hypothesis that selecting the visual rhythm for RE prevents MMPC was tested and confirmed. This hypothesis was preliminarily confirmed in regard to MMPC between two humans. Moreover, to confirm the hypothesis in regard to human–robot cooperation, an experimental system (including a rope-turning robot) was developed. This experimental system allowed experimenters to evaluate the synchronization during MMPC between a human and a robot by measuring the norm of angular velocities. The results of several experiments (namely, a comparison of norms), in which several combinations of visual and auditory rhythmic stimuli were presented to the subjects, strongly supported the hypothesis. 相似文献
106.
Ken -ichi Maruya Kazumi Ito Kazuhito Kushihashi Yoshiho Kishida Kazunari Domen Takaharu Onishi 《Catalysis Letters》1992,14(1):123-126
The CO-H2 reaction over CeO2 catalysts at around 623 K and 67 kPa forms isoprene with about 20% and 70% selectivities in total and C5 hydrocarbons, respectively. The formation of dienes may be due to the low and high activity of CeO2 for alkene and CO hydrogenation, respectively. 相似文献
107.
We fabricated N, S-codoped, N-doped, S-doped TiO2 anatase thin films by a radio-frequency (RF) sputtering method and evaluated the photoelectrochemical and photoinduced hydrophilic activities. The N, S-codoped TiO2 thin film showed obviously higher activities than either the N-doped or S-doped TiO2 under visible light irradiation. The photoinduced hydrophilic activity of the N, S-codoped TiO2 was also greater than that of the undoped TiO2 even under fluorescent light bulb, which contained both visible and UV lights. The high activities of the N, S-codoped TiO2 could be attributed to the hybridization of the introduced N 2p and S 3p, which was supported by the results of ab initio calculations. 相似文献
108.
Tanabe K Hirata N Harada H Hiraoka M Nishimoto S 《Chembiochem : a European journal of chemical biology》2008,9(3):426-432
A characteristic feature of the reactivity of indolequinone derivatives, substituents of which can be removed by one-electron reduction under hypoxic conditions, was applied to the development of a new class of fluorescent probes for disease-relevant hypoxia. A reducing indolequinone parent molecule conjugated with fluorescent coumarin chromophores could suppress efficiently the fluorescence emission of the coumarin moieties by an intramolecular electron-transfer quenching mechanism and a conventional internal-filter effect. Under hypoxic conditions, however, the conjugate, denoted IQ-Cou, underwent a one-electron reduction triggered by X irradiation or the action of a reduction enzyme to release a fluorescent coumarin chromophore, whereupon an intense fluorescence emission with a maximum intensity at 420 nm was observed. The one-electron reduction of IQ-Cou was suppressed by molecular oxygen under aerobic conditions. IQ-Cou also showed intense fluorescence in a hypoxia-selective manner upon incubation with a cell lysate of the human fibrosarcoma cell line HT-1080. The IQ-Cou conjugate has several unique properties that are favorable for a fluorescent probe of hypoxia-specific imaging. 相似文献
109.
Minamiguchi S Takechi M Yuasa T Momota Y Tatehara S Takano H Miyamoto Y Satomura K Nagayama M 《Journal of materials science. Materials in medicine》2008,19(3):1165-1172
Recently, it has become important to develop effective material to be used as scaffolds for bone tissue engineering. Therefore,
we fabricated new three-dimensional (3D) scaffolds consisting of biodegradable poly(d,l-lactide-co-glycolic acid)(PLGA)(75/25) with anti-washout type AC (aw-AC) particles. The aim of this study was to evaluate
this new scaffold concerning its basic properties and biocompatibility. The obtained scaffolds were observed with scanning
electron microscopy (SEM), and measured for porosity, shrinkage and biaxial compressive strengths. It was shown that PLGA
with aw-AC composite scaffolds (aw-AC/PL) showed a greater strength and stability than PLGA scaffolds (PL). Also, the mass
reduction of aw-AC/PL during incubation decreased compared to that of PL. The number of MC3T3-E1 cell in PL and aw-AC/PL was
counted at 5 h, 1 week, and 2 weeks after cell seeding. As a result, aw-AC/PL exhibited a superior performance in terms of
attachment and proliferation compared to PL. Histologically, aw-AC/PL showed an excellent response toward soft tissues. Therefore,
it was shown that aw-AC/PL was more biocompatible than PL. In conclusion, it was strongly suggested that aw-AC/PL was more
useful for cell transplantation than PL in bone tissue engineering. 相似文献
110.