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151.
152.
153.
T. Nishiyama S. Yasuda T. Inamuro 《The European physical journal. Special topics》2009,171(1):145-149
The deformation and breakup processes of a particle-cluster aggregate under shear flows are investigated by the two-phase
lattice Boltzmann method. In the simulation the particle is modeled by a hard droplet with large viscosity and strong surface
tension. The van der Waals attraction force is taken into account for the interaction between the particles. Also, the Brownian
motion is considered for nano-particles. Two important dimensionless parameters are introduced in order to classify calculated
results. One is the ratio of fluid force to the maximum inter-particle force, Y, and the other is the Péclet number which is the ratio of the rate of diffusion by a shear flow to the rate of diffusion
by Brownian motion. It is found that Y is the key factor in dispersion and that the Brownian motion retards the dispersion. 相似文献
154.
Yujiro Hayashi Prof. Dr. Kazuki Obi Yusuke Ohta Daichi Okamura Hayato Ishikawa Dr. 《化学:亚洲杂志》2009,4(2):246-249
Direct and enantioselective : Diphenylprolinol silyl ether was found to catalyze the direct, asymmetric Michael reaction of 4‐substituted 2‐aryl‐2‐oxazoline‐5‐one and α,β‐unsaturated aldehydes, affording the chiral α,α‐disubstituted α‐amino acid derivatives with excellent enantioselectivity.
155.
Xiongchao Lin Keiko Ideta Jin Miyawaki Yonggang Wang Yusuke Nishiyama Seongho Yoon Isao Mochida 《Applied magnetic resonance》2014,45(2):111-123
A general strategy of Al–O–Al structure in various aluminosilicate was evaluated by combining triple-quantum magic angle spinning (3QMAS) and double-quantum homo-nuclear correlation under magic angle spinning (DQMAS) solid-state nuclear magnetic resonance (NMR) measurements with the aid of high magnetic field NMR (800 MHz for 1H Larmor frequency). The results show that in many cases the direct detection of Al–O–Al sites in aluminosilicate crystals and glasses is possible; hence the extent of aluminum avoidance can be directly elucidated. Specifically, experimental evidence of Al–O–Al linkages in several aluminosilicate materials with Si/Al >1 was straightforwardly confirmed; and the existence of Al–O–Al is considered to have little correlation with the Si/Al ratio, but it may be strongly related to the cation and local structural arrangement. In addition, the presence of tri-clusters of (Si, Al)O4-tetrahedra in aluminosilicate framework was proposed, which was thought to act as nuclei for formation and incorporation of cations to achieve charge neutrality. 相似文献
156.
Watanabe Hayato Omura Takuya Okaichi Naoto Kano Masanori Sasaki Hisayuki Arai Jun 《Optical Review》2022,29(4):366-374
Optical Review - Light field displays can display three-dimensional (3D) images with smooth motion parallax without the use of special glasses, by reproducing light ray information from objects.... 相似文献
157.
158.
Yoshiharu Nishiyama Glenn P. Johnson Alfred D. French 《Cellulose (London, England)》2012,19(2):319-336
Powder and fiber diffraction patterns were calculated for model cellulose crystallites with chains 20 glucose units long.
Model sizes ranged from four chains to 169 chains, based on cellulose Iβ coordinates. They were subjected to various combinations
of energy minimization and molecular dynamics (MD) in water. Disorder induced by MD and one or two layers of water had small
effects on the relative intensities, except that together they reduced the low-angle scattering that was otherwise severe
enough to shift the 1 [`1] \bar {1} 0 peak. Other shifts in the calculated peaks occurred because the empirical force field used for MD and minimization caused
the models to have small discrepancies with the experimental intermolecular distances. Twisting and other disorder induced
by minimization or MD increased the breadth of peaks by about 0.2–0.3° 2-θ. Patterns were compared with experimental results.
In particular, the calculated fiber patterns revealed a potential for a larger number of experimental diffraction spots to
be found for cellulose from some higher plants when crystallites are well-oriented. Either that, or further understanding
of those structures is needed. One major use for patterns calculated from models is testing of various proposals for microfibril
organization. 相似文献
159.
Phase unwrapping algorithm based on singularity compensation for three-dimensional shape measurement
Three-dimensional (3D) imaging continues to attract much research interest for its wide applications. In 3D shape measurement, the phase carries information about the object. However, phase mapping is ambiguous as the extracted phase is returned in a form that suffers from 2π phase jumps. In this case, the phase data must be unwrapped to be fit for use. Furthermore, sometimes the presence of noise in the measured data, in which many singular points (SPs) are found, makes general phase unwrapping algorithms fail to produce accurate unwrapped results. For this reason, we propose a new phase unwrapping method for dynamic 3D shape measurement. The new algorithm is based on compensating the singularity of discontinuity sources. It uses direct compensators for adjoining SP pairs and uses rotational compensators for other SP pairs. The proposed algorithm has been evaluated and compared with past phase unwrapping methods. Results show that the proposed method gives satisfactory unwrapped results with a low computation time. 相似文献
160.
Suzuki M Kawamura N Miyagawa H Garitaonandia JS Yamamoto Y Hori H 《Physical review letters》2012,108(4):047201
We show that bulk gold (Au) exhibits temperature-independent paramagnetism in an external magnetic field by x-ray magnetic circular dichroism spectroscopy at the Au L(2) and L(3) edges. Using the sum-rule analysis, we obtained a magnetic moment of 1.3 × 10(-4) μB/atom in an external magnetic field of 10 T and a paramagnetic susceptibility of 8.9 × 10(-6) for the 5d orbit. The induced paramagnetism in bulk Au is characterized by a large (≈ 30%) orbital contribution. This orbital component was retained even when Au atoms formed nanoparticles, playing an important role in stabilizing the spontaneous spin polarization in the Au nanoparticles. 相似文献