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991.
992.
993.
H. Sakuma T. Taniyama K. Ishii Y. Kitamoto Y. Yamazaki 《Journal of magnetism and magnetic materials》2006,300(2):284-292
The order parameter S of Fe–Pt nanoparticles is estimated from X-ray diffraction (XRD) patterns. The total intensity of a diffraction peak is obtained by Rietveld analysis as well as simply integrating the intensity. The Rietveld analysis is found to provide a plausible value of S even for a sample showing an XRD pattern with broad and overlapped peaks. Another order parameter Q, which is obtained from Mössbauer spectra, is introduced, and it is confirmed that Q is equivalent to the probability of Fe atoms being in the L10-type atomic arrangement. The coercivity of Fe–Pt nanoparticles is directly proportional to Q, while it vanishes at S=0.4, indicating that the magnetic property of Fe–Pt nanoparticles has a closer relationship to Q than S. 相似文献
994.
We present two methods for the creation of two-particle entangled states of excitons in a coupled quantum dot system. The system contains two identical quantum dots that are coupled by an inter-dot hopping process. The manipulation of the system is succeeded by proper application of an external laser field. 相似文献
995.
Abbas J. Al-Wattar Baha T. Chiad Wesam A. A. Twej Sarmed S. Al-Awadi 《Central European Journal of Physics》2006,4(3):341-348
The solid host of a laser dye modifies its spectroscopic properties with respect to its liquid host. During the Sol-Gel process
the dye molecules suffer from changing their environment. Two parameters affect this matter, the change in the concentration
due to the evaporation of the solvent (drying) and the caging of dye molecules inside the pores or attachment to the silica
network. Rhodamine 6G absorption and fluorescence spectra with different concentrations, during Sol-Gel time processing, have
been studied. Both, absorption and fluorescence spectra of the dye in the solid host, for different concentrations, show a
blue-shift relative to its liquid phase. 相似文献
996.
997.
[6+4] Cycloaddition reactions of functionalized thiophene dioxides with various fulvenes provided the corresponding azulenes.
The observed regiochemistry was explained in terms of the HOMO—LUMO orbital coefficients.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 137–142, January, 2006. 相似文献
998.
The reactions of acylimines of hexafluoroacetone with 1,3-C,N-binucleophiles giving rise to fluorine-containing 1,4-dihydropyrimidines,
including fused compounds, were studied.
Published in Russian in Izvestiya Akademii Nauk. Seriya Khimicheskaya, No. 4, pp. 706–709, April, 2006. 相似文献
999.
Correlations of active galactic nuclei (AGNs) with microquasars are discussed based on the coexistence of the Blandford-Znajek (BZ) and magnetic coupling (MC) processes (CEBZMC) in black hole (BH) accretion disk.The proportions of several quantities of BH systems for both AGNs and microquasars are derived by combining the observational data with CEBZMC. It is shown that the square of the magnetic field at the BH horizon is inversely proportional to the BH mass, while the accretion rate of the disk is proportional to the BH mass. In addition, the very steep emissivity indexes from the recent XMM-Newton observations of the nearby bright Seyfert 1 galaxy MCG-6-30-15 and the microquasars XTE J1650-500 are well fitted by considering the MC effects on the disk radiation. These results suggest strongly the correlations of A GNs with microquasars. 相似文献
1000.
O. Persyn V. Miri J.‐M. Lefebvre V. Ferreiro T. Brink A. Stroeks 《Journal of Polymer Science.Polymer Physics》2006,44(12):1690-1701
The deformation behavior of miscible PA6/aPA blends films under uniaxial and biaxial tensile drawing has been investigated in relation to blend composition. Whatever be the composition, the initial crystalline structure is ill‐ordered and no evidence of spherulitic morphology was shown. At temperatures beyond the activation of the viscoelastic α relaxation, a ductility improvement upon addition of aPA has been revealed in both uniaxial and biaxial stretching. The decrease in the yield stress with increasing aPA content mainly originates from the reduction in crystal fraction. Regarding the observed evolution in ultimate drawability and strain hardening upon addition of aPA, the latter component of the blend is considered to act as a diluent of the macromolecular network, and the experimental data are fairly well accounted for according to Graessley's theory. © 2006 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 44: 1690–1701, 2006 相似文献