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91.
Tahara T Awatsuji Y Shimozato Y Kakue T Nishio K Ura S Kubota T Matoba O 《Optics letters》2011,36(16):3254-3256
We propose single-shot digital holography which is capable of simultaneously capturing both the information of multiple phase-shifted holograms and the distribution of the polarization. In this technique, a single image sensor records both the information required for phase-shifting interferometry and that of the polarization states of objects using an array of polarizers. The essence of the technique is the capability of imaging the distribution of the polarization of three-dimensional objects with a single-shot exposure by using the space-division multiplexing of holograms. The validity of the proposed technique was confirmed by the preliminary experiments. 相似文献
92.
Aragonite twinning in gastropod nacre 总被引:1,自引:0,他引:1
Hiroki Mukai Kazuko Saruwatari Hiromichi Nagasawa Toshihiro Kogure 《Journal of Crystal Growth》2010,312(20):3014-3019
Aragonite twinning in gastropod nacre has been investigated using scanning electron microscopy (SEM), electron back-scattered diffraction (EBSD), and transmission electron microscopy (TEM) with the focused ion beam (FIB) sample preparation technique. At the growth front of nacre, Haliotis discus hannai and Omphalius rusticus form a “stack-of-coins” structures, which consist of pseudo-hexagonal and elliptical aragonite tablets, respectively. SEM, EBSD, and TEM analyses revealed that these tablets are monolithic single crystal and almost free of the {1 1 0} twins that are common in aragonite of biotic or abiotic origin. The longest diagonal of the hexagon and the longer axis of the ellipse are parallel to the a-axis of aragonite. The crystal orientation of each tablet in a stack, measured by TEM-Kikuchi pattern analysis, is almost the same but there is occasionally {1 1 0} twin-like relationship between adjacent tablets along the stacking. On the other hand, the fibrous aragonite layer formed prior to the nacreous structure is composed of polycrystalline aragonite with high density of {1 1 0} twins. TEM observation suggests that the interlamellar organic sheet prevents the inheritance of the twins, by selecting only single domain of the twins, through the mineral bridge. 相似文献
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95.
Makoto Kudo Tomoyoshi Mishima Satoshi Iwamoto Toshihiro Nakaoka Yasuhiko Arakawa 《Physica E: Low-dimensional Systems and Nanostructures》2004,21(2-4):275
Self-assembled GaSb quantum dots (QDs) with a photoluminescence wavelength longer than 1.3 μm were successfully grown by suppressing the replacement of As and Sb on the surface of the GaSb QDs. This result means that GaSb can thus join InAs or GaInAs as a suitable material for QD lasers for optical communications. 相似文献
96.
Y. Kamii I. Waki H. Fujioka M. Oshima H. Miki M. Okuyama 《Applied Surface Science》2002,190(1-4):348-351
Electrical characteristics of Mg-doped p-GaN activated with Ni catalytic layers have been investigated by means of temperature-dependent Hall effect measurements. It has been revealed that the Ni layer on GaN enhances activation of the acceptor in the whole annealing temperature range. This enhancement is remarkable especially at temperatures below 500 °C and can be attributed to the catalytic effect for the hydrogen desorption. We have found that the donor concentrations in the samples activated with the Ni catalysts are also higher than those activated without Ni. This is probably due to the catalytic effect of Ni for the nitrogen desorption. In addition, it has been found that the ionization energies of the Mg acceptors in GaN activated with the Ni layer are decreased from 170 to 118 meV as the acceptor concentration increases. 相似文献
97.
Keiju Sawada Toshihiro Yamase 《Acta Crystallographica. Section C, Structural Chemistry》2002,58(11):i149-i151
In the crystal structure of the title compound, Na9[Dy(W5O18)2]·35H2O, the complex anion has approximate D4d symmetry, with Dy—O and W—O distances in the ranges 2.355 (6)–2.405 (6) and 1.715 (7)–2.369 (5) Å, respectively. 相似文献
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100.
Brownian dynamics simulations of shear flows are carried out for various suspensions of ellipsoids interacting via the Gay-Berne
potential. In this simulation all the systems of the suspension are in a liquid crystalline phase at rest. In a shear flow
they exhibit various motions of the director depending on the shear rate: the continuous rotation, the intermittent rotation,
the wagging-like oscillation, and the aligning. The director is almost always out of the vorticity plane when it rotates,
that is the kayaking. The number density of the system and the inter-particle potential intensity significantly affect the
shear rate dependence of orientation. In particular, the continuous rotation of director is maintained to higher shear rates
for the system with a stronger potential. Furthermore, the rheological properties are examined. The shear-thinning in viscosity
is observed, but the negative first normal difference is not obtained. 相似文献