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111.
In the presence of spin and pseudospin (p-spin) symmetries, the approximate analytical bound states of the Dirac equation for scalar-vector-tensor Hulth6n potentials are obtained with any arbitrary spin-orbit coupling number using the Pekeris approximation. The Hulth6n tensor interaction is studied instead of the commonly used Coulomb or linear terms. The generalized parametric Nikiforov-Uvarov (NU) method is used to obtain energy eigenvalues and corresponding wave functions in their closed forms. It is shown that tensor interaction removes degeneracy between spin and p-spin doublets. Some numerical results are also given. 相似文献
112.
Akbar B. Aliev Anar A. Kazimov Vusala F. Guliyeva 《Mathematical Methods in the Applied Sciences》2013,36(9):1133-1144
In this paper, we investigate the Cauchy problem for a class of the system of semilinear hyperbolic equations with damping. With the use of the Lp → Lq type estimation for the corresponding linear problem and the method of comparison of functional, the existence and nonexistence criteria of global solutions are found. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
113.
Fateme Banihashemi Amr F. M. Ibrahim Ali Akbar Babaluo Jerry Y. S. Lin 《Angewandte Chemie (Weinheim an der Bergstrasse, Germany)》2019,131(8):2541-2545
Highly b‐oriented, closely packed, MFI zeolite films are prepared on seeded stainless‐steel plates using organic template‐free, secondary growth solutions, containing aluminum sulfate as a crystallization agent. The number of a‐oriented twin crystals is significantly reduced, and even eliminated, simply by restricting the pH value of the secondary growth solution to the narrow range of 11.1–11.3. Values of pH can be adjusted through the controlled addition of (NH4)2SO4 or H2SO4 to secondary growth solutions of the composition (1 SiO2:0.57 NaOH:137.5 H2O:0.0050 (Al2(SO4)3?18 H2O)) or by simply decreasing the molar composition of NaOH with no extra additives. 相似文献
114.
We determine the local density of states of one-dimensional incommensurate charge-density wave states in the presence of a strong impurity potential, which is modeled by a boundary. We find that the charge-density wave gets pinned at the impurity, which results in a singularity in the Fourier transform of the local density of states at momentum 2k_{F}. At energies above the spin gap we observe dispersing features associated with the spin and charge degrees of freedom, respectively. In the presence of an impurity magnetic field we observe the formation of a bound state localized at the impurity. All of our results carry over to the case of 1D Mott insulators by exchanging the roles of spin and charge degrees of freedom. We discuss the implications of our result for scanning tunneling microscopy experiments on spin-gap systems such as two-leg ladder cuprates. 相似文献
115.
It is shown that the differential form of Friedmann equations of Friedman--Robertson--Walker (FRW) universe can be recast as a similar form of the first law ThdSh = dE + WdV of thermodynamics at the apparent horizon of FRW universe filled with the viscous fluid. It is also shown that by employing the general expression of temperature associated with the apparent horizon of an FRW universe and assumed that the temperature Tm of the energy inside the apparent horizon is proportional to the horizon temperature Tm= bTh, we are able to show that the generalized second law of thermodynamics holds in the Einstein gravity provided Th-Tm/r~A ≤(ρ+P~). 相似文献
116.
Li Jiaojiao Mohammadi Amin Maleki Akbar 《Journal of Thermal Analysis and Calorimetry》2020,139(4):2691-2703
Journal of Thermal Analysis and Calorimetry - Microgas turbines are one of the most well-known technologies for distributed generation. Unfortunately, their efficiency is not as high as it should... 相似文献
117.
118.
Elahe Yazdani Farzane Pazoki Arefe Salamatmanesh Masoume Jadidi Nejad Maryam Kazemi Miraki Akbar Heydari 《应用有机金属化学》2020,34(10):e5855
Copper supported on magnetite nanoparticles modified with environmentally friendly ligand tricine was devised for synthesis of acetamides via C–C oxidative cleavage of ketones with amines. The catalyst was characterized using different techniques, including Fourier transform infrared, X-ray diffraction, scannin electron microscopy, vibrating sample magnetometry, thermogravimetric analysis, and energy dispersive x-ray spectroscopy. The protocol showed relatively high yields of acetamide products. Furthermore, the magnetic recovery of the catalyst rendered the overall process fast and efficient. It was used in the reaction for six consecutive cycles with negligible loss of catalytic activity. This research is the first report of application of magnetic nanocatalysts for synthesis of acetamides from ketones of low activity through a C–C bond cleavage strategy. 相似文献
119.
120.
Fatemeh Jafari Mehmandoost-Khajeh-Dad Ali Akbar Mohammadi-Dadkan Maysam Ghal-Eh Nima Yazdandoust Hamideh 《Physics of Particles and Nuclei Letters》2019,16(6):761-767
Physics of Particles and Nuclei Letters - Plastic scintillators are widely used in detecting nuclear radiation due to their low construction cost, the ability to be produced in nearly any shape and... 相似文献