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101.
102.
The orbital symmetry of the order parameter in UPt3 is determined by evaluating transport coefficients. The result leads to an order parameter of either the non-unitary bipolar state:
or the unitary planar state:
where
, or
with the hexagonal unit vectors
and
. The d vector is rotatable in the plane spanned by
and
perpendicular to
under weak applied c-axis field. Experiments are proposed to distinguish between these equally possible states. 相似文献
103.
N Masaki K Machida H Kado K Yokoyama T Tohda 《Chemical & pharmaceutical bulletin》1991,39(7):1899-1901
The atomic force microscope has been developed and used to image arrays of molecules at the (001) and (100) faces of aspirin crystals in water and in air. Lattice spacings composed of methyl groups and the part of the phenyl groups on the surface of the (001) in water, are consistent with X-ray diffraction data. The surface of (100) face which shows most perfect cleavage in bulk, is more difficult to image. This initial success in imaging at drug crystal surfaces clarified the different structural behavior at the submolecular level for three crystal faces, and the close relationship to the differences in the dissolution velocity. 相似文献
104.
The effects of anisotropic gap structures on a diamagnetic response are investigated in order to demonstrate that the field-angle-resolved magnetization [ML(chi)] measurement can be used as a spectroscopic method to detect gap structures. Our microscopic calculation based on the quasiclassical Eilenberger formalism reveals that ML(chi) in a superconductor with a fourfold gap displays a fourfold oscillation reflecting the gap and Fermi-surface anisotropies, and the sign of this oscillation changes at a field between Hc1 and Hc2. As a prototype of unconventional superconductors, magnetization data for borocarbides are also discussed. 相似文献
105.
It is proposed that the spatially modulated superfluid phase, or the Fulde-Ferrell-Larkin-Ovchinnikov state could be observed in resonant fermion atomic condensates which are realized recently. We examine optimal experimental setups to achieve it by solving the Bogoliubov-de Gennes equation for both idealized one-dimensional and realistic three-dimensional cases. The spontaneous modulation of this superfluid is shown to be directly imaged as the density profiles either by optical absorption or by Stern-Gerlach experiments. 相似文献
106.
Takechi H Oda Y Nishizono N Oda K Machida M 《Chemical & pharmaceutical bulletin》2000,48(11):1702-1710
In order to find a highly sensitive fluorophore, 3-azolyl-7-diethylaminocoumarin derivatives were synthesized. Both the absorption and fluorescence maxima of the coumarin-thiazole compounds showed red shifts with increases of the molar absorptivities and fluorescence intensities, in comparison with those of the corresponding coumarin-oxazole compounds. Among them, 3-(5-ethoxycarbonyl-1,3-thiazol-2-yl)-7-diethylamino-2H-chromen -2-one (3e) was one of the most promising candidates as a fluorophore accessible for analytical purposes in the fields of analytical and biological chemistry. 相似文献
107.
Quantum mechanics allows quantum nondemolition (QND) variables to be measured without being changed. This requires QND variables to be initially in an eigenstate and measurement backaction noise to be directed into conjugate variables. Experimental demonstrations thus require two measurements: the first to collapse variables toward an eigenstate and the second to show results identical to the first. Here, we report results from two successive soliton-collision QND measurements that optical correlation measurements show to be nearly identical. 相似文献
108.
It is pointed out theoretically that a single electron band model is able to exhibit the interchange of two phases: itenerant band ferromagnetism and superconductivity. Our theory is based on the molecular field approximation applied for a simplified electron-electron interaction. Possible phase changes are discussed in connection with two phase transitions of ferromagnetism and superconductivity in the intermetallic compound Y4Co3. 相似文献
109.
110.
The luminescence properties of Eu(II)-borates and Eu2+-activated Sr-borates were studied, e.g. Sr1?xEuxB2O4Sr1?xEuxB4O7 and Sr1?xEuxB6O10. It was found that Sr1?xEuxB4O7 consisting of a three-dimensional network of BO4 tetrahedra gave a remarkably stronger emission than the other compound consisting of BO3-3 ions, B2O4-5 ions, (BO2)∞ chains or a (B3O5)∞ network. This was understood by considering their crystallographic properties and with help of the Dexter theory. 相似文献