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141.
Hossein Mehri-Dehnavi Behrouz Mirza Hosein Mohammadzadeh Robabeh Rahimi 《Annals of Physics》2011,(5):1320-1333
We study quantum discord, in addition to entanglement, of bipartite pseudo-entanglement in noninertial frames. It is shown that the entanglement degrades from its maximum value in a stationary frame to a minimum value in an infinite accelerating frame. There is a critical region found in which, for particular cases, entanglement of states vanishes for certain accelerations. The quantum discord of pseudo-entanglement decreases by increasing the acceleration. Also, for a physically inaccessible region, entanglement and nonclassical correlation are evaluated and shown to match the corresponding values of the physically accessible region for an infinite acceleration. 相似文献
142.
Morteza Sohrabi Akbar Irandoukht Hosein Brijanian 《Reaction Kinetics and Catalysis Letters》2006,88(1):127-133
Summary In the present study, twenty four catalysts for low pressure methanol synthesis were prepared according to a pre-designed
research program consisting of three stages. In each stage, applying the experimental design techniques, a number of catalysts
were synthesized by the co-precipitation method, using different proportions of metal salts solutions. The activities of the
catalysts were determined applying a laboratory scale continuous packed bed reactor. It was noted that the calcinations temperature,
ageing time and molar ratio of metal nitrates to precipitant, had the highest effects on the activity of the catalysts. 相似文献
143.
Y. Hatsukawa Y. Toh M. Oshima A. Kimura M. Hosein Mahmudy Gharaie 《Journal of Radioanalytical and Nuclear Chemistry》2007,271(1):43-45
In this study, sensitive trace element analyses were carried out without chemical separation by the combination of neutron
activation analysis and multi-parameter coincidence spectroscopy. A long-lived radioisotope 129I in algae samples and iridium in geological samples were analyzed. 相似文献
144.
Monolayer films from polystyrene asymmetric dimer colloidal particles were formed on a silicon substrate using a heat assisted vertical deposition technique. In dilute particle suspensions of systematically varied concentrations, the system maximizes the packing efficiency within a thin meniscus region. Structures with positional order and orientational order in and out of the substrate plane were observed in surface and cross-sectional scanning electron microscopy (SEM) images. The confining effect of the meniscus height drove the formation of the resulting oblique and hexagonal lattices with controlled orientation. The crystals exhibited features similar to the planes of the boron nitride and zinc sulfide atomic structures. The diffraction properties of both colloidal crystal structures were demonstrated via selected area diffraction for laser light in the visible region. 相似文献
145.
146.
Synthesis and Characterization of the 2‐Methylaminopyridine‐functionalized Polystyrene Resin‐supported Pd(II) Catalyst for the Mizoroki–Heck and Sonogashira Reactions in Water
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A new polystyrene‐anchored Pd(II) pyridine complex is synthesized and characterized. This Pd(II) pyridine complex behaves as a very efficient heterogeneous catalyst in the Heck reaction of methyl acrylate with aryl halides and the Sonogashira reaction of terminal alkynes with aryl halides in water. Furthermore, the catalyst shows good thermal stability and recyclability. This polymer‐supported Pd(II) catalyst could easily be recovered by simple filtration of the reaction mixture and reused for more than five consecutive trials without a significant loss in its catalytic activity. 相似文献
147.
An efficient shooting method for fiber amplifiers and lasers 总被引:1,自引:0,他引:1
Zohreh Lali-Dastjerdi Feisal Kroushavi Mohammad Hosein Rahmani 《Optics & Laser Technology》2008,40(8):1041-1046
A simple shooting method is proposed for the design of distributed multi-pumped Raman fiber amplifiers (RFAs) and Yb-doped double-clad fiber lasers (DCFLs). Using the proposed method a distributed RFA with 10 pump sources and 1700 mW total input pump power is simulated and high-power Yb-doped DCFL rate equations are solved numerically. The numerical simulation results show that the proposed method has good convergence in the condition of increasing numbers and power of input pump sources. 相似文献
148.
Sayyed Mostafa Habibi Khorassani Malek Taher Maghsoodlou Ali Ebrahimi Hosein Roohi Mohammad Zakarianezhad Hamid Reza Dasmeh 《Phosphorus, sulfur, and silicon and the related elements》2013,188(5):1103-1115
The major objectives of the work undertaken were to carry out kinetic studies of the reaction between triphenylphosphine and dialkyl acetylenedicarboxylate in the presence of strong NH-acids, such as carbazole. To determine the kinetic parameters of the reaction, it was monitored by the UV spectrophotometer technique. The values of the second order rate constant (k 2 ) were automatically calculated using standard equations within the program when the second order fits of the mentioned reactions were automatically drawn by the software associated with a Cary UV spectrophotometer model Bio-300 at an appropriate wavelength. At the temperature range studied, the dependence of the second order rate constant (Ln k) on reciprocal temperature was in agreement with the Arrhenius equation. This provided the relevant plots to calculate the activation energy of all reactions. Furthermore, useful information was obtained from studies of the effect of solvent and different alkyl groups within the dialkyl acetylenedicarboxylates on the rate of reactions. 相似文献
149.
The cohomology with trivial coefficients of the Lie algebra ? of Hamiltonian vector fields in the plane and of its maximal nilpotent subalgebra L 1? is considered. The cohomology H 2(L 1?) is calculated, and some far-reaching conjectures concerning the cohomology of the Lie algebras mentioned above and based on an extensive experimental material are formulated. 相似文献
150.
While polymers are known as thermal insulators, recent studies show that stretched single chains of polymers have a very high thermal conductivity. In this work, our new simulation scheme for simulation of heat flow in nanoconfined fluids [H. Eslami, L. Mohammadzadeh, and N. Mehdipour, J. Chem. Phys. 135, 064703 (2011)] is employed to study the effect of chain ordering (stretching) on the rate of heat transfer in polyamide-6,6 nanoconfined between graphene surfaces. Our results for the heat flow in the parallel direction (the plane of surfaces) show that the coefficient of thermal conductivity depends on the intersurface distance and is much higher than that of the bulk polymer. A comparison of results in this work with our former findings on the heat flow in the perpendicular direction, with the coefficient of heat conductivity less than the bulk sample, reveal that well-organized polymer layers between the confining surfaces show an anisotropic heat conduction; the heat conduction in the direction parallel to the surfaces is much higher than that in the perpendicular direction. The origin of such anisotropy in nanometric heat flow is shown to be the dramatic anisotropy in chain conformations (chain stretching) beside the confining surfaces. The results indicate that the coefficients of heat conductivity in both directions, normal and parallel to the surfaces, depend on the degree of polymer layering between the surfaces and the pore width. 相似文献