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Maroufi B. Laghmach R. EL Hadfi H. Daoud M. 《International Journal of Theoretical Physics》2021,60(8):3103-3114
The quantum Fisher information defined via the symmetric logarithmic derivative and the skew information are two different aspects describing the information contents of quantum mechanical density operators. They are considered as natural generalizations of the classical Fisher information and constitute key ingredients in the emerging field of quantum metrology. In this paper, we give the analytical expression of quantum Fisher information and skew information for two-qubit system prepared in a two-qubit state of X type.
相似文献14.
K. Bahedi M. AddouM. El Jouad Z. SofianiH. EL Oauzzani B. Sahraoui 《Applied Surface Science》2011,257(18):8003-8005
Nanocrystalline ZnO:Al thin films were deposited by reactive chemical pulverization spray pyrolysis technique on heated glass substrates at 450 °C to study their crystalline structure, composition, strain, stress, roughness characteristics and nonlinear optical susceptibility as a function of Al concentration (0, 2, 3, 5 at.%). The films were characterized by X-ray diffractometer (XRD), EDAX 9100 analyser, atomic force microscopy (AFM) and third harmonic generation (THG). The Al (3 at.%) doped ZnO thin films exhibited the lower strain/stress than undoped films. The nonlinear properties of the ZnO:Al thin films have been found to be influenced by the films strain/stress. 相似文献
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Styrene butadiene (SBR) and natural rubber (NR) can be used as binding matrices to control the release of zinc (Zn) which is a micro-nutrient for plants. The leaching rate of zinc in an aqueous medium depends on the concentration of zinc sulphate loaded in the two types of rubber used, the temperature of the surrounding environment and the pH of the aqueous medium. Water uptake was increased with increasing concentration of ZnSO4. The sustained release of zinc ions from the investigated formulations was prolonged for over five months. The mechanical properties of the vulcanizates were affected as the concentration of zinc sulphate changed. 相似文献
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Bruijnincx PC Buurmans IL Huang Y Juhász G Viciano-Chumillas M Quesada M Reedijk J Lutz M Spek AL Münck E Bominaar EL Klein Gebbink RJ 《Inorganic chemistry》2011,50(19):9243-9255
The newly synthesized dinuclear complex [Fe(III)(2)(μ-OH)(2)(bik)(4)](NO(3))(4) (1) (bik, bis(1-methylimidazol-2-yl)ketone) shows rather short Fe···Fe (3.0723(6) ?) and Fe-O distances (1.941(2)/1.949(2) ?) compared to other unsupported Fe(III)(2)(μ-OH)(2) complexes. The bridging hydroxide groups of 1 are strongly hydrogen-bonded to a nitrate anion. The (57)Fe isomer shift (δ = 0.45 mm s(-1)) and quadrupole splitting (ΔE(Q) = 0.26 mm s(-1)) obtained from Mo?ssbauer spectroscopy are consistent with the presence of two identical high-spin iron(III) sites. Variable-temperature magnetic susceptibility studies revealed antiferromagnetic exchange (J = 35.9 cm(-1) and H = JS(1)·S(2)) of the metal ions. The optimized DFT geometry of the cation of 1 in the gas phase agrees well with the crystal structure, but both the Fe···Fe and Fe-OH distances are overestimated (3.281 and 2.034 ?, respectively). The agreement in these parameters improves dramatically (3.074 and 1.966 ?) when the hydrogen-bonded nitrate groups are included, reducing the value calculated for J by 35%. Spontaneous reduction of 1 was observed in methanol, yielding a blue [Fe(II)(bik)(3)](2+) species. Variable-temperature magnetic susceptibility measurements of [Fe(II)(bik)(3)](OTf)(2) (2) revealed spin-crossover behavior. Thermal hysteresis was observed with 2, due to a loss of cocrystallized solvent molecules, as monitored by thermogravimetric analysis. The hysteresis disappears once the solvent is fully depleted by thermal cycling. [Fe(II)(bik)(3)](OTf)(2) (2) catalyzes the oxidation of alkanes with t-BuOOH. High selectivity for tertiary C-H bond oxidation was observed with adamantane (3°/2° value of 29.6); low alcohol/ketone ratios in cyclohexane and ethylbenzene oxidation, a strong dependence of total turnover number on the presence of O(2), and a low retention of configuration in cis-1,2-dimethylcyclohexane oxidation were observed. Stereoselective oxidation of olefins with dihydrogen peroxide yielding epoxides was observed under both limiting oxidant and substrate conditions. 相似文献
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ABSTRACTHydrogen storage reactions on Ni ? C59X(X = B, N) heterofullerene are investigated by using the state-of-the-art density functional theory calculations. The Ni atom prefers to bind at the bridge site between two hexagonal rings, and can bind up to five hydrogen molecules with average adsorption energies of (?0.94, ?0.48, ?0.33, ?0.25 and ?0.20 eV) per hydrogen molecule for Ni ? C59B, while (?1.20, ?0.60, ?0.41, ?0.28 and ?0.23 eV) per hydrogen molecule for Ni ? C59N. With no metal clustering, the system gravimetric capacities are expected to be as large as 10.87 and 10.85 wt % for 5H2NiC59B?and 5H2NiC59N, respectively. While the desorption activation barriers of the complexes 1H2 + C59X?(X = B, N)?are outside the Department of Energy domain (?0.2 to ?0.6 eV), the desorption activation barriers of the complexes nH2 + C59X(X = B, N)(n = 2 ? 5) are inside this domain. The hydrogen storage of the irreversible 1H2 + NiC59X?(X = B, N) and reversible 2H2 + NiC59X?(X = B, N) interactions is characterised in terms of density of states and projected densities of states, pairwise and non-pairwise additivity, infrared, Raman, electrophilicity and molecular electrostatic potentials. 相似文献
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Abstract The top part of the coexistence curve of methyl fluoride in the critical region has been determined first by direct observation of the disappearance of the meniscus of the fluid situated in a high-pressure light scattering cell and subsequently from the measured maximum depolarization ratio of an appreciable number of isochores close to the critical point. The experimental data obtained from direct observations yield a coexistence curve which nearly coincides with that found recently from pVT measurements. However, the data obtained from light scattering experiments describe a gravity induced coexistence curve which lies above the previous one and which shows a minimum at the critical point. The complete experimental data have been used to evaluate the critical parameters pc, ρc and Tc and the critical exponent β. 相似文献
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The chemical compositions of silicate minerals, sulphide minerals and metal Fe-Ni in theQingzhen meteorite were measured by the microprobe analyses. Based upon these chemicalcompositions, the cosmochemical behaviour and characteristics of the existing forms of themajor elements in the Qinzhen meteorite have been discussed. These characteristics show thatunder the S-rich, O-poor, and strongly reducing conditions, the light metal elements, such asCa, Mg, K, Na may form sulphide, and metal Fe-Ni may contain Si and P. However, we con-sider that the light metal-sulphide can be stable in the lower mantle and there are some Siand P in the Fe-Ni core. Finally, an earth core-mantle model is established, where the Fe-Ni core contains some Si and P; the lower mantle is composed of Mg-rich silicate, SiO_2 andsulphide; the upper mantle, of silicate and oxide. 相似文献
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