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41.
We study the time evolution of the quantum Fisher information of a system whose the dynamics is described by the phase-damped model. We discuss the correlation between the Fisher information and entanglement dynamics of a qubit and single-mode quantized field in a coherent state inside phase-damped cavity. Analytic results under certain parametric conditions are obtained, by means of which we analyze the influence of dissipation on the negativity and quantum Fisher information for different values of the estimator parameter. An interesting monotonic relation between the Fisher information and nonlocal correlation behavior is observed during the time evolution. 相似文献
42.
We study the nonlocal correlations and quantum entanglement for two deformed bosonic fields of arbitrary deformation parameters, q 1 and q 2, prepared in an entanglement of deformed coherent states. As a measure of entanglement, we use the von Neumann entropy and investigate its behavior for different strength regimes of the optical fields. We find that the photon number can enhance the von Neumann entropy, and the deformation parameters can restrain the system entanglement. 相似文献
43.
44.
C. Djega-Mariadassou P. Rougier J. L. Dormann H. Kadiri A. Berrada 《Hyperfine Interactions》1989,45(1-4):343-350
The interesting steps of the crystallization process of two types of amorphous ribbons Fe50Ni30B12Sie and Fe72Cr9Si0·3P9C10 have been detected and locked by the Joule heating method. This method reveals instantaneously with high reproductibility the various steps but Mössbauer spectroscopy seems the most adequate technique to evaluate the crystallinity rate during the crystallization process. 相似文献
45.
Synthèse et étude structurale de dérivés substitués en -2 du thiazolidine carboxylate d'éthyle-4 (R)
Abdesselam Hamri Marie-Hlne Pra Houda Fillion 《Journal of heterocyclic chemistry》1987,24(6):1629-1633
Pharmacological properties of thiazolidine derivatives are of great interest. For this purpose we prepared two series: 2-hydroxyalkyl-4-carbethoxythiazolidines and 2-carbalkoxyalkyl-4-carbethoxythiazolidines. Their syntheses involve a condensation reaction between L-carbethoxy-cystein and several α-hydroxyketones or β-ketoesters. Compounds 4 and 5 was obtained as an unequal mixture of diastereoisomers. Protons nmr spectra at 300 MHz in the presence of trifluoroacetic acid shows a modification of diastereoisomer percentages which indicate the existence of an equilibrium through an imminium ion intermediate. Therefore, the stereoselectivity observed reflects the relative stability of the different diastereoisomers. 相似文献
46.
A. Chouak P. Vuister G. Paic M. Berrada J. Csikai 《Journal of Radioanalytical and Nuclear Chemistry》1978,45(2):445-451
A gamma-spectrometric method independent of radon escape for the determination of U and Ra in rock samples based on the 63 keV and 1001 keV as well as 185 keV lines is described and discussed. A simple experimental procedure is given for the determination of the self-absorption factor. The method has been applied for the determination of uranium and radium in rock samples from Morocco containing uranium between 17.5 wt.% and 0.026 wt.%. The limits of determination, at 95% confidence level and 10% standard deviation, for the 63 keV and 1001 keV lines were found to be 0.075 wt.% and 0.62 wt.%, respectively, using samples of 6 g and chosing 1 h measuring time. 相似文献
47.
Recently photon-added states that could be detected through the emission rather than the absorption of electromagnetic radiation have been actively explored and investigated. In this paper, we construct the photon-added power-law-potential coherent states (PA-PLPCSs) using generalized Heisenberg algebra. The Klauder minimal set of conditions required to obtain coherent states are satisfied. We study nonclassical effects associated with PA-PLCSs using the Mandel parameter and discuss some of their intriguing nonclassical behavior. These states have interesting significance and can be realized experimentally, exhibiting highly nonclassical behavior that depends on the degree of excitation and other parameters. Finally, we study the dynamics of entanglement and quantum discord for two-mode state within the framework of PLPCSs and show that the sudden death and sudden birth of correlations are due to the change and transfer of the correlation between one mode and its environment, using the monogamic relation between the entanglement and quantum discord. 相似文献
48.
Zakaria Benzekri Sara Sibous Houda Serrar Ali Ouasri Said Boukhris Ali Rhandour Abdelaziz Souizi 《Journal of the Iranian Chemical Society》2018,15(12):2781-2787
In this work, the condensation of aromatic aldehydes with different two-substituted aniline catalyzed by NH3(CH2)5NH3BiCl5 as heterogeneous and recyclable catalyst was reported. It was demonstrated that NH3(CH2)5NH3BiCl5 can act as an efficient and active catalyst and is reusable for six runs without a significant loss of their catalytic activity. Simple preparation of the catalyst, high catalytic activity and good reusability are noteworthy advantages of this catalytic system in the synthesis of benzoxazole, benzimidazole and benzothiazole heterocycles at room temperature under solvent-free conditions. 相似文献
49.
S. Abdel-Khalek K. Berrada Y. S. El-Saman M. Abdel-Aty 《Journal of Russian Laser Research》2012,33(5):437-447
We study the time evolution of the total and Pancharatnam phase of four-level atoms in the presence of a one-dimensional photonic-band-gap material. We obtain analytical and numerical results under certain parametric conditions and analyze the effect of a Kerr-like medium and the detuning parameter on the dynamics of the Pancharatnam phase for the initial atomic position. We observe an interesting feature of the Pancharatnam phase for the one-dimensional photonic-band-gap material. 相似文献
50.
Kamal Berrada 《Journal of Russian Laser Research》2018,39(6):533-543
We study the time evolution of the classical and quantum correlations for interacting and noninteracting two-qubit systems under the influence of noncorrelated and correlated environmental models. We discuss the dependence of different physical quantifiers on the environment parameters. Interestingly, we examine the effects of the initial state and different system parameters on the evolution of correlations of the system of qubits in contact with different kinds of environments. We show how the interaction among qubits can protect and preserve the correlation loss during the time evolution for various environmental models. Moreover, we examine the competition between the dissipative and coherent effects in different kinds of correlations dynamics of the system of qubits. Our study gives a deeper understanding on the correlations for a wide variety of the environment models, which is rather significant in different tasks of quantum optics and information. 相似文献