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101.
The phase diagrams of the CuGaS2-CuI and CuGaSe2-CuI pseudobinary systems are investigated. Both systems show eutectic behavior; liquids along the liquids curves for solute concentrations of more than 15 mol% are shown to be single phase and solids in equilibrium with the liquids are demonstrated to be CuGaS2 and CuGaSe2 chalcopyrite compounds. On the basis of the results, bulk crystals of CuGaS2 and CuGaSe2 are prepared from CuI solutions using the Bridgman technique. The photoluminescence spectra of these crystals are nearly the same as those of the crystals grown by iodine transport method. 相似文献
102.
On the basis of the itinerant-localized duality theory of spin fluctuations, the puzzling aspects of the neutron scattering experiments in the normal state of high-Tc cuprates are clarified from a global point of view. The dynamical spin structure factor exhibits two different aspects depending on the energy transfer ω. At lower energies, ω < ωc, where ωc is the fermion coherence energy, the spectrum is coherent so that the characteristic scales for wavevector and energy are temperature dependent, while at higher energies, ω > ωc, the spectrum is incoherent so that those characteristic scales are temperature independent. The integrated weight of the coherent part of the spectrum exhibits the so-called “spin gap” behavior when the Fermi surface of the itinerant fermion is technically nested, even though there is no excitation gap in the spectrum at all. 相似文献
103.
We introduce some Mordell curves of two different natures both of which are associated to cubic fields. One set of them consists of those elliptic curves whose rational points over the rational number field are described by or closely related to cubic fields. The other is a one-parameter family of Mordell curves which gives all (cyclic) cubic twists and all quadratic twists of the Fermat curve X3+Y3+Z3=0. 相似文献
104.
Norimichi Tsumura Daisuke Kawazoe Toshiya Nakaguchi Nobutoshi Ojima Yoichi Miyake 《Optical Review》2008,15(6):292-294
A simple regression-based model of skin diffuse reflectance is developed based on reflectance samples calculated by Monte
Carlo simulation of light transport in a two-layered skin model. This reflectance model includes the values of spectral reflectance
in the visible spectra for Japanese women. The modified Lambert Beer law holds in the proposed model with a modified mean
free path length in non-linear density space. The averaged RMS and maximum errors of the proposed model were 1.1 and 3.1%,
respectively, in the above range. 相似文献
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Arylhydrazines reacted with benzene in the presence of trifluoromethanesulfonic acid (TFSA) to give aminobiphenyls. This is a general method for the synthesis of aminobiphenyls. 相似文献
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