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51.
F. Ogino Professor T. Sakano T. Mizushina Professor Emeritus 《Heat and Mass Transfer》1987,21(2-3):87-93
An analysis and measurement were made of momentum and heat transfers from fully developed turbulent flow in an eccentric annulus to inner and outer tube walls. The eddy diffusivities of momentum and heat obtained in the turbulent flow in a circular tube were applied to the annular flow in the analysis. The result indicates that the calculated friction factor and average Nusselt numbers on the inner and outer tube walls are in fairly good agreement with the measurements. 相似文献
52.
Previously, the authors reported “Nematic Ordered Cellulose (NOC)” that is a well-ordered state of β-1,4-glucan chains without
exhibiting typical X-ray diffraction patterns of any cellulose polymorphs (Togawa and Kondo 1999; Kondo et al. 2001; Kondo 2007). The NOC was prepared by stretching water-swollen gel-like films at the draw ratio of 2.0 to provide highly oriented β-1,4-glucan
molecular chains of cellulose, which was proved by the high resolution TEM observation. In this paper, a detailed study of
the unique ordered state of the NOC was attempted to characterize orientation of the main chains as well as the OH groups
of molecules using polarized FTIR accompanied with a vapor-phase deuteration method. The dichroic analysis suggested that
the main chains were fairly oriented in the stretching direction whereas the OH groups remained unoriented. The disordered
state of the OH groups regardless of the oriented state for the main chain may hinder the oriented crystallization during
the preparation of NOC films. 相似文献
53.
Okano K Ogino S Kawamoto M Yamashita T 《Chemical communications (Cambridge, England)》2011,47(43):11891-11893
We demonstrated the formation of a photoinduced surface relief grating using thin films comprising a photochromic molecular motor, 9-(2-phenyl-2,3-dihydro-cyclopenta[a]naphthalen-1-ylidene)-9H-fluorene. Results show that mass migration occurred by patterned light irradiation prepared from interfered laser beams and a photomask. 相似文献
54.
55.
Fluid flow in a rotating cylindrical container of radius Rw and height H with a co-axially rotating disk of radius Rd at the fluid surface is numerically investigated. The container and the disk rotate with angular velocities Ωw and Ωd, respectively. We solve the axisymmetric Navier-Stokes equations using a finite-volume method. The effects of the relative directions and magnitudes of the disk and container rotations are studied. The calculations are carried out with various ratios of Ωw and Ωd for H/Rw = 2 and Rd/Rw = 0.7. Streamlines and velocity vectors in the meridional plane and azimuthal velocities are obtained. The flow fields in the meridional plane are discussed with relation to azimuthal velocities in the interior of the container. The numerical results are also compared with experimental data. 相似文献
56.
Takumi Higashiyama Akihiro Katsuyama Hideki Otori Toru Kamimura Atsushi Uehara Miho Kainuma Ryo Takumi Yukako Kudo Masayuki Ebina Katsumi Mochitate Tasuku Kon Yasubumi Furuya Hideaki Kikuchi 《Ultrasonics》2014
The rat lung epithelial cell line SV40-T2 was used to develop a cellular biosensing system to assay for environmental toxicants. The novel approach on which this system is based involves direct attachment of cultured rat or human cells onto a cell-adhesive matrix on the device through which shear horizontal surface acoustic waves (SH-SAW) are transmitted using 50 MHz SAW resonator. This novel design enables sensitive monitoring of changes of the electrophysical characteristics of cells, such as their conductivity and relative permittivity. A time-dependent change of phase of SAW and change of insertion loss (change of amplitude) were observed when the cells were treated with 0.5 or 1.0 mM H2O2. The change of insertion loss was biphasic, with an early phase (1–3 h) and a late phase (3–6 h). The late phase coincided with the destruction of cell–cell tight junctions detected by measurement of the transepithelial electrical resistance and paracellular permeability; in contrast, the early phase coincided with the destruction of intracellular actin filaments by H2O2. The early-phase effect of H2O2 on phase shift may be attributable to the change of intracellular permittivity by a change of cellular polarity. Immunofluorescence microscopy showed the disappearance of zonula occludens protein 1 from the region of cell–cell contact. These results suggest the correlation between the change of insertion loss as an SAW parameter and the destruction of tight junctions of the cells on the SH-SAW device in the late phase. 相似文献
57.
S. Horii M. Yamaki H. Ogino T. Maeda J. Shimoyama 《Physica C: Superconductivity and its Applications》2010,470(20):1056-1059
We report the grain-orientation effects under a modulated rotation magnetic field for Y-based cuprate superconductors and LaFeAsO (La1111). Tri-axial orientation has been successfully achieved only for orthorhombic Y2Ba4Cu7Oy and YBa2Cu4O8 powders without a twin microstructure, while separation of three crystallographic axes could not be observed in twinned YBa2Cu3Oy (Y123) and tetragonal La1111 powders. The morphology of grains, in addition to the symmetry of crystal structures, seriously affects the degrees of tri-axial orientation, which means that the control of twin microstructures is required for the tri-axial magnetic orientation in Y123. 相似文献
58.
Polystyrene (PSt)/poly (4-butyltriphenylamine; PBTPA) composite particles was prepared by a chemical oxidative seeded dispersion
polymerization of (4-butyltriphenylamine) with PSt seed particles that were prepared by nonaqueous dispersion polymerization
of styrene. Monodisperse composite particles were obtained when the ratio of monomer to seed, the rate of monomer feed, and
poly(N-vinyl pyrrolidone; PVP) concentration was appropriately selected. The introduction of PBTPA was confirmed by the presence
of the characteristic absorption band attributed to PBTPA from a Fourier transform infrared spectra. The solvent extraction
with ethyl acetate revealed that composite particles consisted of PSt core and PBTPA shell. Then two-dimensional arrays of
composite particles were also fabricated. 相似文献
59.
Adsorption of phenol from an aqueous solution in batch and continuous flow systems using carbon gels with a microhoneycomb structure (carbon gel microhoneycombs, CMHs) was studied. The obtained monolithic CMHs had fairly straight channels, 25–45 μm in diameter, and the thickness of the walls which form the channels was around 5 μm. The CMHs showed 370 times lower hydraulic resistance when compared with a column packed with particles having the same diffusion path length as it. The obtained CMHs have a hierarchical micro-meso porous structure giving BET surface area in the range of 513–1070 m2·g?1.When used for phenol adsorption from an aqueous solution, the CMHs quickly adsorbed phenol at first, and then, the uptake gradually increased, which indicates that the adsorption mechanism is based on not only simple physisorption. The phenol adsorption capacity increased with the increase in carbonization temperature of the CMH and the decrease in its hydrophilicity. CMHs carbonized at temperatures higher than 1073 K showed the highest phenol adsorption capacity which was around 160 mg·g?1. The CMHs could continuously adsorb phenol from aqueous solutions, and their length of unused bed (LUB) values depended on operation conditions but were in the range of 0.3–0.7 cm. The experimental results indicated that carbon cryogels with a microhoneycomb structure have a high potential to be used for effective separation of phenol. 相似文献
60.
Dr. Karl Ridier Dr. Béatrice Gillon Dr. Arsen Gukasov Dr. Grégory Chaboussant Dr. Alain Cousson Prof. Dominique Luneau Dr. Ana Borta Dr. Jean‐François Jacquot Dr. Ruben Checa Yukako Chiba Prof. Hiroshi Sakiyama Prof. Masahiro Mikuriya 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(2):724-735
Polarized neutron diffraction (PND) experiments were carried out at low temperature to characterize with high precision the local magnetic anisotropy in two paramagnetic high‐spin cobalt(II) complexes, namely [CoII(dmf)6](BPh4)2 ( 1 ) and [CoII2(sym‐hmp)2](BPh4)2 ( 2 ), in which dmf=N,N‐dimethylformamide; sym‐hmp=2,6‐bis[(2‐hydroxyethyl)methylaminomethyl]‐4‐methylphenolate, and BPh4?=tetraphenylborate. This allowed a unique and direct determination of the local magnetic susceptibility tensor on each individual CoII site. In compound 1 , this approach reveals the correlation between the single‐ion easy magnetization direction and a trigonal elongation axis of the CoII coordination octahedron. In exchange‐coupled dimer 2 , the determination of the individual CoII magnetic susceptibility tensors provides a clear outlook of how the local magnetic properties on both CoII sites deviate from the single‐ion behavior because of antiferromagnetic exchange coupling. 相似文献