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61.
Fatih Ozaydin Azmi Ali Altintas Sinan Bugu Can Yesilyurt Metin Arik 《International Journal of Theoretical Physics》2014,53(9):3219-3225
We study the quantum Fisher information (QFI) of a system of several particles which is in a superposition of a GHZ and two W states with arbitrary relative phase. We show that as the number of particles increases from 3 to 4, the behavior of QFI drastically changes. We also show how the dependence of QFI on the relative phase weakens as the number of particles increases. We also analyze the QFI for the state for several instances of N due to the change of the relative phases. 相似文献
62.
M. ErdemÖ. Özturk E. YucelS.P. Altintas A. VarilciC. Terzio?lu I. Belenli 《Physica B: Condensed Matter》2011,406(3):705-709
We have investigated the effect of addition of Gd in Bi1.8Pb0.35Sr1.9Ca2.1Cu3GdxOy superconductor with x=0, 0.1, 0.2, 0.3, 0.4 and 0.5. The samples were prepared using the standard solid-state reaction method. The activation energies, irreversibility fields (Hirr), upper critical fields (Hc2) and coherence lengths at 0 K (ξ(0)) were calculated from the resistivity versus temperature (R-T) curves under DC magnetic fields up to 7 T. The superconducting transition temperature, Tc, and activation energy, U0, were found to decrease with increase in Gd concentration and with increase in applied magnetic field. The offset transition temperature of the pure (Gd00) sample without applied magnetic field is 108 K, whereas for Gd05 sample, the offset transition temperature drops to 5 K with 7 T applied magnetic field. The activation energy of the Gd00 sample without applied magnetic field is 34,980 K, and for Gd05 sample with 7 T applied field it is 98 K. Hirr and Hc2 values also decrease with increase in Gd addition. The possible reasons for the observed degradation in microstructural and superconducting properties due to Gd addition were discussed. 相似文献
63.
There are approximately 82 million of tons asphaltites reserves in ?irnak, East Anatolia of Turkey. The present study was investigated to employ ashes of S?rnak BCW (burned coal waste) as an ion exchange in removal of important toxic metal, Lead (Pb), in high yields by adsorption. The ion exchange characteristics of lead onto BCW from aqueous solution were investigated with respect to the changes in pH of solution, adsorbent dosage, initial metal ion concentration, contact time and temperature of solution. For the adsorption of lead, the Langmuir isotherm model fitted to equilibrium data better than the Freundlich isotherm model. Thermodynamic functions, the change of free energy (ΔG°), enthalpy (ΔH°) and entropy (ΔS°) of adsorption were also calculated for lead. These parameters showed that the adsorption was feasible, spontaneous and exothermic at 293–333 K. Experimental data were also evaluated in terms of kinetic characteristics of adsorption. The batch kinetic data were correlated to the pseudo-first order and pseudo-second order models. The data fitted better to the pseudo-second order equation. The activation energy of systems was determined. Experimental data have shown that BCW that was used in unmodified form; as low cost, readily available ion exchange; can be used for removal of lead from industrial waste waters. Analysis was determined using Flame Atomic Absorption Spectrometry (FAAS). 相似文献
64.
Ultrasonic destruction of bisphenol-A: the operating parameters 总被引:4,自引:1,他引:3
Degradation of bisphenol-A (BPA) by ultrasonic irradiation at 300 kHz was investigated at varying substrate concentrations, pH, hydroxyl radical scavengers and sparge gases. It was found that increases in BPA initial concentration slowed down the reaction rate, but enhanced the sonochemical product yield. Both the rate of reaction and the product yield were adversely affected by pH elevation above the neutral level. The degree of BPA decay was fastest in the presence of air due to the formation of acids and excess radicals, and slowed down as the gas was replaced by argon and oxygen. The impact of large concentrations of hydroxyl radical scavengers such as carbonate and t-butanol was to decrease the rate of degradation, particularly when the scavenger concentration was considerably larger than that of BPA, and the deceleration was more remarkable in the presence of t-butanol than in that of carbonate. 相似文献