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51.
The boundary of the zone in which sputtered atoms are thermalized in the substrate–target drift space during the ion-plasma magnetron deposition of films is determined theoretically and experimentally. A comparison of the thicknesses of films deposited on the front and back sides of substrates situated at different distances from the target makes it possible to divide the flow of atoms sputtered toward substrates into direct and diffusion flows and to determine the dimensions of the spatial zone in which sputtered atoms are thermalized. The experimental data are in quantitative agreement with the results of a statistical simulation of the thermalization process of atomic particles during the ion-plasma deposition. This simulation enables optimization of the technology of defect-free growth of films with uniform thickness on substrates with complex 3D configuration. 相似文献
52.
In order to model the adsorption of xylan on cellulose, we have simulated, at the atomic level, the gas phase adsorption of
small xylan fragments having 5 skeletal β (1 → 4) xylosyl residues (X5), using molecular dynamics simulations. A first regime was considered, corresponding to a low surface coverage, with the
adsorption of isolated X5 in various initial orientations. In this regime, the simulation indicated that X5 moved toward extended conformations, some of them being helical, with the possibility of either 21 or left-handed 31 helices. During the simulation, the X5 fragments became preferentially oriented, parallel or anti parallel with respect to the cellulose chain axis. Substitution
of the X5 backbone by either GlcA and/or Araf side chains had no major influence on either the conformation or the efficiency of the
interaction. However, the presence of side chains favored orientations of the X5 backbone inclined with respect to the cellulose chain axis. In a second regime corresponding to monolayer coverage, the geometrical
features of the adsorption of the xylan fragments on cellulose was roughly the same as that in the individual coverage situation.
In this case, the monolayer became equilibrated at 0.14 g of xylan fragments for each g of cellulose, a figure that compared
favourably with the values obtained in experimental adsorption of xylan on bacterial cellulose. 相似文献
53.
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
54.
Vera I. Filyakova Nadezhda S. Boltacheva Marina G. Pervova Valery N. Charushin 《Mendeleev Communications》2021,31(3):388-389
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55.
Yubing Dong Amand Faessler Thomas Gutsche Valery E. Lyubovitskij 《Few-Body Systems》2013,54(7-10):1011-1014
The new resonances X(3872) and Λ c (2940) are considered as weakly bound states of other hadrons in a molecule scenario using phenomenological Lagrangians. 相似文献
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Nosova Emiliya V. Batanova Olga A. Mochulskaya Nataliya N. Charushin Valery N. 《Chemistry of Heterocyclic Compounds》2019,55(6):578-582
Chemistry of Heterocyclic Compounds - We have developed an efficient synthetic approach to potential antibacterial agents with double mechanism of action through the combination of antibacterial... 相似文献
59.