DSpace Собрание:http://hdl.handle.net/11701/94242020-01-23T03:36:35Z2020-01-23T03:36:35ZElectrosurface and adsorption properties of nanodimensional chromium oxideKolonitskii, Petr D.Dolin, Denis M.Sukhodolov, Nikolai G.http://hdl.handle.net/11701/94922018-04-27T00:06:33Z2018-03-01T00:00:00ZНазвание: Electrosurface and adsorption properties of nanodimensional chromium oxide
Авторы: Kolonitskii, Petr D.; Dolin, Denis M.; Sukhodolov, Nikolai G.
Краткий осмотр (реферат): Electrosurface and adsorption properties of chromium oxide(III) prepared by nitrate and reducing
agent combustion under microwave irradiation is considered in this work. This method of synthesis
provides the opportunity to obtain nanoparticles quickly. Electrosurface properties of the obtained chromium oxide(III) were studied. Point of zero charge for Cr2O3 in solutions of KCl with different
concentration (10−1–10−3 mole/l) has been determined by the potentiometric titration method
(pHzcp = 7.1). Following obtained data adsorption of H+ and OH− ions on the surface of oxide
was calculated. No effect of electrolyte concentration on pHzcp was found. Dependence of specific
electrical conductivity and pH on time has been studied. It was determined that the equilibrium
in the system is established within first 2 hours after contact of the oxide and solution. Based
on electrophoretic mobility data electrokinetic potential for chromium oxide(III) was calculated
(pHIEP = 7.1).2018-03-01T00:00:00ZLaws of change of thermodynamic properties of 3d compounds — elements(II) — fluorides and chloridesNasriddinov, Subhiddin K.Badalov, Abdulhayr B.http://hdl.handle.net/11701/94912018-04-27T00:06:36Z2018-03-01T00:00:00ZНазвание: Laws of change of thermodynamic properties of 3d compounds — elements(II) — fluorides and chlorides
Авторы: Nasriddinov, Subhiddin K.; Badalov, Abdulhayr B.
Краткий осмотр (реферат): The possibility of using a semi-empirical method for the evaluation of the thermodynamic properties
of fluorides and chlorides 3d metals in the oxidation state (+2) and the establishment of
regularities of their changes depending on the nature of the metal cations and anions is presented.
The method developed by Poluektov N. S. and his colleagues takes into account the peculiarities
of the electronic structure of 3d metals and their influence on the determined properties of the
compounds. The calculated values of the thermodynamic characteristics — enthalpy of formation,
entropy and heat capacity – for the more studied of the chlorides 3d metal compounds are
in good agreement with the reference. This demonstrates the competence of the method for the
calculation and evaluation of unknown characteristics of 3d metals. The most complete information
about the thermodynamic characteristics of fluorides and chlorides 3d metals defined and/or
refined by this method are obtained. It is found that the patterns of variation of these properties
depending on the nature of the cations and anions are complex. The curves of these patterns which are dependent on the nature of metal are separated by subgroups based on the partial (for
manganese ions) or full (for zinc ions) filling of 3d-orbitals by electrons. According to characteristics,
copper and chromium compounds fall outside the general pattern. The equations expressing
these curve patterns for subgroups 3d metals are here compiled.2018-03-01T00:00:00ZExchange of aryl groups in Friedel — Crafts alkylation of arenes in superacid by 2-halogeno- 2-trifluoromethylstyrenes. Mechanism and ways of suppressionSandzhieva, Maria A.Muzalevskiy, Vasiliy M.Nenajdenko, Valentine G.Vasilyev, Aleksander V.http://hdl.handle.net/11701/94902018-04-27T00:06:34Z2018-03-01T00:00:00ZНазвание: Exchange of aryl groups in Friedel — Crafts alkylation of arenes in superacid by 2-halogeno- 2-trifluoromethylstyrenes. Mechanism and ways of suppression
Авторы: Sandzhieva, Maria A.; Muzalevskiy, Vasiliy M.; Nenajdenko, Valentine G.; Vasilyev, Aleksander V.
Краткий осмотр (реферат): The protonation of 2-halogeno-2-trifluoromethylstyrenes in superacids leads to formation of benzyl
carbocations that are capable to take part in Friedel — Crafts reaction with arenes to afford 1,1-
diaryl-2-halo-3,3,3-trifluoropropanes. The reaction with strong π-nucleophiles (xylenes, anisole or
veratrole) can be complicated by exchange of aryl groups. The mechanism and ways of suppression
of this additional process were proposed.2018-03-01T00:00:00ZA study of acridine adsorption on silica by the methods of luminescence and IR spectroscopyRozhkova, Yuliia A.Malkin, Vladimir M.Korotkov, Valentin I.Tsyganenko, Alexey A.http://hdl.handle.net/11701/94892018-04-27T00:06:37Z2018-03-01T00:00:00ZНазвание: A study of acridine adsorption on silica by the methods of luminescence and IR spectroscopy
Авторы: Rozhkova, Yuliia A.; Malkin, Vladimir M.; Korotkov, Valentin I.; Tsyganenko, Alexey A.
Краткий осмотр (реферат): Spectra of luminescence and its excitation as well as IR spectra of acridine adsorbed from the gas
phase or from the solution in dichloromethane on silicon dioxide (mesoporous MCM-41 and aerosil)
have been studied. The luminescence band of adsorbed acridine is shifted towards longer waves
as compared with the spectrum of acridine in dichloromethane and towards short wavelengths
with respect to the spectrum of protonated acridine in solution. In the IR spectrum, acridine
adsorption leads to a frequency shift of the band of surface silanol groups from 3750 to 2860 cm−1
and to the appearance of absorption bands of the adsorbed acridine. Addition of SO2 results in
acridine protonation with the shift of the 1624 band to 1653 cm−1. The obtained data indicate
that acridine forms hydrogen bond with silanol groups of silica surface. In the case of acridine
adsorption from dichloromethane, or after extended storage of the sample in acridine vapor, the
luminescence band is observed at 520 nm, that is explained by self-association of acridine.2018-03-01T00:00:00ZTheory φ3 in the dimension d = 3 in frames of η-expansionPismensky, Artem L.http://hdl.handle.net/11701/94882019-12-27T07:10:00Z2018-03-01T00:00:00ZНазвание: Theory φ3 in the dimension d = 3 in frames of η-expansion
Авторы: Pismensky, Artem L.
Краткий осмотр (реферат): The method of η-expansion calculation in the scalar field model with φ3 interaction in a 3D
euclidian space based on conformal bootstrap equations is used in the present paper. As we
know, there is an ε-expansion technique that allows us to find the critical exponent in the form of
a series in powers of ε, the deviation of the dimension of space from the logarithmic one. However,
the logarithmic dimension of the theory φ3 is 6, and the given series in ε have a very small radius
of convergence, so that it is not possible to extend it analytically to the dimension d = 3. To
solve the problem, we propose using the η-expansion: we construct the series in powers of critical
exponent η supposing that it is a small value and obtain some approximate equation for η. If we
consider this equation as precise, then it proves that there is no sustainable solution. But using
the Pad´e approximant we receive a stable root of equation.2018-03-01T00:00:00ZCritical behaviour of a O(n)-symmetric model with antisymmetric tensor order parameter: Four-loop approximationLebedev, Nikita M.Kompaniets, Mikhail V.http://hdl.handle.net/11701/94872018-04-27T00:06:30Z2018-03-01T00:00:00ZНазвание: Critical behaviour of a O(n)-symmetric model with antisymmetric tensor order parameter: Four-loop approximation
Авторы: Lebedev, Nikita M.; Kompaniets, Mikhail V.
Краткий осмотр (реферат): The critical behavior of the O(n)-symmetric φ4 model with an antisymmetric tensor order parameter
is studied by means of the renormalization group approach. Previously, this model was
studied in the framework of the three-loop approximation by means of ε-expansion with conformal
Borel resummation technique and pseudo-ε-expansion. It was shown that the results of
these approaches are in qualitative agreement with each other, however, the numerical values
of the critical indices can differ quite significantly. Moreover, the question of the sensitivity of
even qualitative results to the accounting of the higher orders of perturbation theory remained
open. In the present paper, the RG functions and critical indices of the model are calculated up
to four-loop accuracy within both approaches. Their analysis shows that the results of applying
different approaches are qualitatively consistent both with each other and with the results of the
three-loop analysis.2018-03-01T00:00:00ZBorel summation of the dynamic index z in the model A of critical dynamics with an account of the strong coupling asymptoticsVorobyeva, Svetlana Ye.Ivanova, Ella V.Serov, Vitalii D.http://hdl.handle.net/11701/94862018-04-27T00:06:27Z2018-03-01T00:00:00ZНазвание: Borel summation of the dynamic index z in the model A of critical dynamics with an account of the strong coupling asymptotics
Авторы: Vorobyeva, Svetlana Ye.; Ivanova, Ella V.; Serov, Vitalii D.
Краткий осмотр (реферат): In this paper we consider the model A of critical dynamics which describes the dynamic characteristics
of the critical behavior of ferromagnets as well as other systems with a nonconserved
order parameter. For such a model the renormalization group method and the ε-expansion are
the common tool for constructing consistent perturbative expansion for critical exponents and
other universal quantities. One of the problems in this formalism is the asymptotic nature of the
series obtained within the ε-expansion, so to get reliable theoretical predictions it is necessary to
apply the Borel resummation technique. In this work we apply such a resummation technique to
the four-loop ε-expansion of the dynamical exponent z which describes the critical slowing down in the ferromagnet-type systems. The motivation of the paper is twofold: 1) improved values for
the coefficients of the ε-expansion have recently been obtained, 2) sit has been shown that incorporation
of strong coupling asymptotics into the Borel resummation technique leads to better
convergence of the resummation procedure for static models. In this investigation it was shown
that taking into account the asymptotics of the strong coupling for critical static problems also
improves the predictions of the higher terms of the series. Since the strong-coupling asymptotic
for this model is unknown, this parameter is held free and adjusted in accordance with the condition
of the most accurate prediction of the last known term from the previous ones and the rate
of convergence of the procedure.2018-03-01T00:00:00ZComparison of carboplatin and cisplatin effects on DNA structure in solutionAlekseev, Georgy V.Kasyanenko, Nina A.http://hdl.handle.net/11701/94852018-04-27T00:06:35Z2018-03-01T00:00:00ZНазвание: Comparison of carboplatin and cisplatin effects on DNA structure in solution
Авторы: Alekseev, Georgy V.; Kasyanenko, Nina A.
Краткий осмотр (реферат): The formation of complexes of high molecular thymus DNA with coordination compounds of platinum(
II) cisplatin and carboplatin has been examined. The absorption spectra, circular dichroism
spectra, DNA melting and change in reduced viscosity of DNA solutions containing different concentrations
of platinum compounds have been analyzed. It was shown that DNA interacts with cisplatin and carboplatin in a solution containing 0.005M NaCl. The nitrogenous bases of macromolecules
participate in binding. Spectral changes of DNA and the dependence of the reduced
viscosity of DNA solutions on the concentration of platinum compounds show similar features in
complex formation when using cisplatin and carboplatin, but at the same time they also indicate
differences in the influence of cisplatin and carboplatin on DNA structure. Apparently, unlike the
interchain cross-linking formed by cisplatin, carboplatin binds to a single DNA strand.2018-03-01T00:00:00Z