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71.
72.
G. A. Mikhailov 《Computational Mathematics and Mathematical Physics》2012,52(1):137-145
A comparative analysis of various models of exponentially correlated random fields associated with Poisson point ensembles
is given. Algorithms for the modeling of radiative transfer in random media of this type are considered. An asymptotic estimate
for the particle passage probability is constructed assuming that the flow of trajectory intersections with domains of constant
random density is Poisson distributed. 相似文献
73.
A. A. Greshnov Yu. B. Vasil’ev N. N. Mikhailov G. Yu. Vasil’eva D. Smirnov 《JETP Letters》2013,97(2):102-106
Cyclotron-resonance measurements in 21-nm-thick HgTe/CdHgTe quantum wells of different crystallographic orientations have been performed. It has been found that, in contrast to the structures with the (001) orientation of the quantum-well plane, (013)-oriented quantum wells are semimetallic and their absorption spectra exhibit both electron and hole cyclotron-resonance lines. The simultaneous presence of the two types of charge carriers originates from an overlap between the upper heavy-hole quantum-confinement subbands hh1 and hh2. This overlap is caused by the strong interaction of these subbands with the Dyakonov-Khaetskii interface state. Calculations carried out using the eight-band kp-Hamiltonian indicate that, for known values of the band-structure parameters, the overlap between hh2 and hh1 subbands does not occur; this result is in agreement with the cyclotron-resonance data for (001)-oriented structures. The enhanced interaction between heavy-hole and interface states owing to the existence of steps at low-symmetry heterointerfaces may be the mechanism responsible for the appearance of an overlap between subbands in HgTe quantum wells with orientation different from (001). 相似文献
74.
Highly Efficient One‐Pot Preparation of 1,2,4‐Oxadiazoles in the Presence of Diazabicycloundecene 下载免费PDF全文
New highly efficient method for the cyclization of acylamidoximes in the presence of diazabicycloundecene was developed and incorporated into a general and practical one‐pot synthesis of 1,2,4‐oxadiazoles (11 examples, 85–97% yields). 相似文献
75.
Oleg G. Salnikov Kirill V. Kovtunov Danila A. Barskiy Valery I. Bukhtiyarov Robert Kaptein Igor V. Koptyug 《Applied magnetic resonance》2013,44(1-2):279-288
Parahydrogen-induced polarization has been successfully used for a kinetic study of propylene hydrogenation over a Pt/Al2O3 catalyst. It was shown that the reaction orders with respect to hydrogen are different for the pairwise and the non-pairwise hydrogen addition and are equal to 0.7 and 0.1, respectively. This observation of different reaction orders confirms the coexistence of different types of active sites which are responsible for the overall and the pairwise hydrogen addition to the propylene C=C double bond. Moreover, 0.7 reaction order with respect to H2 for pairwise hydrogen addition indicates that the contribution of pairwise addition depends on the concentration of molecular hydrogen. Therefore, this observation can be developed into a practical tool for producing fluids with highly polarized nuclear spins by changing the hydrogen concentration. 相似文献
76.
V. S. Kovivchak T. V. Panova K. A. Mikhailov 《Journal of Surface Investigation: X-ray, Synchrotron and Neutron Techniques》2012,6(1):64-66
The formation of periodical structures, and also, micro- and nanoparticles on a polycrystalline magnesium and aluminum surface
under high power proton-carbon beam irradiation has been investigated. The spatial parameters of these structures and particle
sizes have been determined. The possible mechanisms for periodical structure formation have been considered. 相似文献
77.
78.
V. F. Ivanov D. A. Gordon I. A. Shilova V. A. Lesnichaya A. I. Mikhailov E. Ya. Misochko 《Russian Journal of Applied Chemistry》2016,89(8):1292-1295
New composite lignocellulose materials were prepared using modified lignin and nanocellulose. The materials were studied by elemental and thermal gravimetric analysis, and their tensile tests were performed. The results obtained show that addition of nanocellulose to modified lignin makes possible its use as filler in paper production. 相似文献
79.
G. A. Mikhailov 《Numerical Analysis and Applications》2014,7(2):147-158
Some numerical algorithms for the simulation of random variables and functions, as well as for parametrical numerical statistical analysis are considered. Specifications and explanations of the algorithms important for practical purposes are given. 相似文献
80.