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991.
M. Yu. Barabanenkov D. V. Kalyabin S. A. Nikitov 《Journal of Experimental and Theoretical Physics》2020,130(4):549-554
Simultaneous quantum correlations between two spins in magnetic nanostructures are considered in the model of a linear chain of a finite number of atoms with exchange interaction between electron spins of neighboring atoms in the framework of the Heisenberg ferromagnetism theory. We assume that in the initial state, the spins of all chain atoms except the first two are oriented along the same direction. The spins of the first two atoms are flipped. Due to the exchange interaction, this initial state generates a spin flip wave along the chain. The expressions obtained for nonstationary quantum amplitudes of the flip probability waves for an even number of spins can be used for calculating quantum correlations between two spins separated by a large distance in a chain. Numerical calculations of the spin correlator reveal that the correlation between two spins in the chain occurs with a delay on the order of the time of propagation of the exchange interaction along the spin chain. After the delay, the spin correlation amplitude abruptly increases followed by subsequent oscillatory temporal behavior. 相似文献
992.
Afonin A. G. Bogolyubsky M. Yu. Volkov A. A. Elumakhov D. K. Zapolsky V. N. Ivanilov A. A. Kalinin A. Yu. Krinitsyn A. N. Kulagin N. V. Kryshkin V. I. Patalakha D. I. Romanishin K. A. Skvortsov V. V. Talov V. V. Turchanovich L. K. Chesnokov Yu. A. 《Physics of Atomic Nuclei》2020,83(2):228-236
Physics of Atomic Nuclei - The invariant cross sections for forward charged-hadron production at zero angle in carbon–carbon collisions at a beam kinetic energy of 19.6 GeV per nucleon were... 相似文献
993.
Subbotin M. L. Gostev A. A. Anashkin I. O. Belov A. M. Levin I. V. Kolbasov B. N. Kolesnikova E. A. Kravchuk V. L. Maltsev S. G. Nikolaev A. V. Filimonova E. A. 《Physics of Atomic Nuclei》2020,83(7):1131-1144
Physics of Atomic Nuclei - The Ignitor tokamak nuclear fusion research project is one of the most ambitious initiatives undertaken under the long-term scientific cooperation program between the... 相似文献
994.
Pt alloys with transition metals supported on carbon substrates are used as improved cathode electrocatalysts for fuel cells. Enhanced catalytic activity is attributed to the structure (Pt-Pt bond distance) and/or electronic effect (Pt d-electron vacancy). This work focuses on the development of Pt3Co/f-MWCNT catalysts (functionalized multiwalled carbon nanotubes [f-MWCNT]) using ethylene glycol as the dispersing and reducing agent. The aim is to in parallel achieve fine dispersion, quantitative deposition and alloy formation. As described herein, the pH value of the reaction suspension has a critical effect on the composition and morphology of the synthesized nanoparticles. High pH values favor the formation of Pt3Co alloy, nevertheless negatively influencing the dispersion. A discussion is made on the reduction/deposition mechanism and how to control the conditions to result in optimum properties. 相似文献
995.
996.
Kalienko M. S. Zhelnina A. V. Volkov A. V. Leder M. O. Tolstykh N. A. Bocharov A. I. 《Crystallography Reports》2020,65(6):844-848
Crystallography Reports - The thermal conductivities of seven titanium alloys (VT1-0, VT18U, VT20, IMI834, Ti6242S, Ti6Al4V, and Ti6Al7Nb) have been measured. According to the data obtained, the... 相似文献
997.
998.
999.
The (1+2)-dimensional chiral nonlinear Schrödinger equation (2D-CNLSE) as a nonlinear evolution equation is considered and studied in a detailed manner. To this end, a complex transform is firstly adopted to arrive at the real and imaginary parts of the model, and then, the modified Jacobi elliptic expansion method is formally utilized to derive soliton and other solutions of the 2D-CNLSE. The exact solutions presented in this paper can be classified as topological and nontopological solitons as well as Jacobi elliptic function solutions. 相似文献
1000.
Kulyako Yu. M. Trofimov T. I. Pilyushenko K. S. Vinokurov S. E. Myasoedov B. F. 《Physics of Atomic Nuclei》2020,83(10):1396-1399
Physics of Atomic Nuclei - The use of microwave heating to produce solid solutions of actinide oxides in the processes of thermal denitration of model nitric acid solutions formed in reducing... 相似文献