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51.
52.
Aleksander Yevtushenko Michal Kuciej Olena Yevtushenko 《Archive of Applied Mechanics (Ingenieur Archiv)》2011,81(6):715-726
The transient temperature field and corresponding quasi-static thermal stresses are analysed in a system consisting of a semi-space
and a strip. The strip is heated on its outer surface by a heat flux with the intensity equal to the specific power of friction
during braking with a uniform retardation. The evolution and distribution in depth from a surface of friction for temperatures
and thermal stresses were investigated for the metal-ceramic FMK-11 material of the strip. 相似文献
53.
Dawid Maliszewski Agnieszka Wrbel Beata Kolesiska Justyna Frczyk Danuta Drozdowska 《Molecules (Basel, Switzerland)》2021,26(13)
A series of new analogs of nitrogen mustards (4a–4h) containing the 1,3,5-triazine ring substituted with dipeptide residue were synthesized and evaluated for the inhibition of both acetylcholinesterase (AChE) and β-secretase (BACE1) enzymes. The AChE inhibitory activity studies were carried out using Ellman’s colorimetric method, and the BACE1 inhibitory activity studies were carried out using fluorescence resonance energy transfer (FRET). All compounds displayed considerable AChE and BACE1 inhibition. The most active against both AChE and BACE1 enzymes were compounds A and 4a, with an inhibitory concentration of AChE IC50 = 0.051 µM; 0.055 µM and BACE1 IC50 = 9.00 µM; 11.09 µM, respectively. 相似文献
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Madhuri Mukhopadhyay Debi Banerjee Aleksander Koll Aleksander Filarowski Samaresh Mukherjee 《Chemical physics letters》2006,420(4-6):316-320
The effect of neutral, cationic and anionic micellar environments on the ground and excited state proton transfer reactions of salicylidine-3,4,7-methyl amine (SMA) in water has been studied by steady state and time resolved fluorescence spectroscopy. In the ground state, the formation of the primary form of SMA is enhanced at the expense of the zwitterionic species due to micellization. In the excited state, anion formation decreases both in the presence of Triton-X and cetyl trimethyl ammonium bromide (CTAB). However, in the presence of sodium dodecyl sulphate (SDS), the anionic emission increases after reaching a certain micellar concentration. The lifetime of the anion is significantly reduced in CTAB compared to that in the bulk water and also in the presence of Triton-X. It is proposed that the destabilization and modification of SMA anion occurs due to the different electrostatic environments produced by micellization. 相似文献
56.
In the first part of the paper we give a construction of a topological degree theory for set-valued tangent vector fields with convex and nonconvex values defined on nonsmooth closed subsets of a Banach space. The obtained homotopy invariant is an extension of the classical degree for vector fields on manifolds. In the second part we propose a fixed-point index for inward maps on arbitrary closed convex sets. 相似文献
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Aleksander Jablonski 《Surface science》1985,151(1):166-182
A Monte Carlo algorithm is proposed for calculating the elastic reflection coefficient, ηE, for elements. The algorithm accounts for the multiple elastic scattering of electrons in solids. The calculated values of ηE compare well with the literature data for elements with atomic number up to 47 and at primary energies above 2 keV. The proposed Monte Carlo method makes it possible to determine the functional relation between ηE and the inelastic mean free path, λ. This relation turned out to be non-linear, arid it deviates from a similar relation based on published earlier single elastic scattering model. The deviation is especially pronounced for elements with medium atomic numbers. The calculated function offers a convenient method for determining the inelastic mean free path. The values of λ derived in the present work from published experimental values of ηE compare very well with the literature data. 相似文献
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