Zobrazeno 1 - 10
of 121
pro vyhledávání: '"Roumen Tsekov"'
Autor:
Dimitar Shandurkov, Nina Danchova, Tony Spassov, Vesselin Petrov, Roumen Tsekov, Stoyan Gutzov
Publikováno v:
Gels, Vol 9, Iss 8, p 663 (2023)
A novel, one-pot sol–gel preparation scheme leading to reproducible incorporation of 20–40 nm sized gold nanoparticles (AuNPs) in SiO2 gels is developed based on in situ reduction during gelation using chloroauric acid and ascorbic acid. Variatio
Externí odkaz:
https://doaj.org/article/c16d7ff3e73a40879e7da12884f53581
Autor:
Roumen Tsekov
Publikováno v:
Reports in Advances of Physical Sciences, Vol 1, Iss 3, Pp 1750008-1-1750008-6 (2017)
The quantum Liouville equation, which describes the phase space dynamics of a quantum system of fermions, is analyzed from stochastic point of view as a particular example of the Kramers–Moyal expansion. Quantum mechanics is extended to relativisti
Externí odkaz:
https://doaj.org/article/a563adf087ed4a268c0aa1bf6eb94398
Autor:
Roumen Tsekov
Publikováno v:
International Journal of Molecular Sciences, Vol 2, Iss 2, Pp 66-71 (2001)
Abstract: A new approach to quantum Markov processes is developed and the corresponding Fokker-Planck-like equation is derived. The latter was examined to reproduce known results from classical and quantum physics. It was also applied to the phase-sp
Externí odkaz:
https://doaj.org/article/2c7b41798084456cb571e7db023b0cf5
Two types (with and without a hydrolysis stabilizer) of polyamide 6.6 (PA6.6) reinforced with 30% w/w glass fibres were examined against the influence of automotive cooling fluids, e.g. ethylene glycol aqueous solutions. The overall goal was to find
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::8d73938b460db52d4e1a25a2a7af4be6
https://epb.bibl.th-koeln.de/files/2004/PI_PI6323.pdf
https://epb.bibl.th-koeln.de/files/2004/PI_PI6323.pdf
Publikováno v:
Plasmonics. 15:371-377
The spectra of small gold nanoparticles (GNPs) were theoretically described following the modified Mie equations and by adopting the Kriebig-Drude model. The experimental dependence of the absorption maximal intensity of small spherical GNPs versus t
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::c4c1ec77f0719e98bfb40c4b9d810b16
https://doi.org/10.1007/s11468-019-01034-4
https://doi.org/10.1007/s11468-019-01034-4
Autor:
Roumen Tsekov
The Schrodinger equation is solved for many free particles and their quantum entanglement is studied via correlation analysis. Converting the Schrodinger equation in the Madelung hydrodynamic-like form, the quantum mechanics is extended to open quant
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::63cb1ba05497d450a06f018f334dcf1b
Autor:
Roumen Tsekov
Publikováno v:
Coatings, Vol 10, Iss 597, p 597 (2020)
The slip effect in wetting films is theoretically studied, and a nonlinear dependence of the hydrodynamic velocity on the slip length is discovered. It is demonstrated that the hydrodynamic flow is essentially affected by the presence of a nonuniform
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::948e2f9fd4a2a7a7bd12a8b96140e111
https://www.mdpi.com/2079-6412/10/6/597
https://www.mdpi.com/2079-6412/10/6/597
Autor:
Stoyan I. Karakashev, Roumen Tsekov, Nirav Raykundaliya, Silviya Simeonova, Nikolay A. Grozev, Gert Heinrich, Klaus Werner Stöckelhuber
Publikováno v:
Colloids and Surfaces A: Physicochemical and Engineering Aspects. 555:638-645
This is an original study on the rubbing of ruptured bubbles on a hydrophobic solid surfaces. A bubble protruding from a capillary tube attached to the objective of a microscope was pressed gently against a hydrophobic solid surface by gradually incr
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::5a3b80d37a870b08fe9ffec4933f3bc1
https://doi.org/10.1016/j.colsurfa.2018.07.037
https://doi.org/10.1016/j.colsurfa.2018.07.037
Autor:
Roumen Tsekov
Publikováno v:
Physics Letters A. 382:2230-2232
The Klein-Kramers equation, governing the Brownian motion of a classical particle in quantum environment under the action of an arbitrary external potential, is derived. Quantum temperature and friction operators are introduced and at large friction
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::459ebb91b2c3dd8df519257c4492f979
https://doi.org/10.1016/j.physleta.2017.06.037
https://doi.org/10.1016/j.physleta.2017.06.037