We consider the first boundary value problem for a second-order differential-difference equation with variable coefficients on the interval
. The existence of a generalized solution is proved. We ...investigated the smoothness of generalized solutions on
and explicitly obtained linearly independent functions to which the right-hand side of the differential-difference equation must be orthogonal.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
This article presents the first experimental data on the ability of microbial communities from sediments of the Gorevoy Utes natural oil seep to degrade petroleum hydrocarbons under anaerobic ...conditions. Like in marine ecosystems associated with oil discharge, available electron acceptors, in particular sulfate ions, affect the composition of the microbial community and the degree of hydrocarbon conversion. The cultivation of the surface sediments under sulfate-reducing conditions led to the formation of a more diverse bacterial community and greater loss of
n
-alkanes (28%) in comparison to methanogenic conditions (6%). Microbial communities of both surface and deep sediments are more oriented to degrade polycyclic aromatic hydrocarbons (PAHs), to which the degree of the PAH conversion testifies (up to 46%) irrespective of the present electron acceptors. Microorganisms with the uncultured closest homologues from thermal habitats, sediments of mud volcanoes, and environments contaminated with hydrocarbons mainly represented microbial communities of enrichment cultures. The members of the phyla
Firmicutes
,
Chloroflexi
, and
Caldiserica
(OP5), as well as the class
Deltaproteobacteria
and
Methanomicrobia
, were mostly found in enrichment cultures. The influence of gas-saturated fluids may be responsible for the presence in the bacterial 16S rRNA gene libraries of the sequences of “rare taxa”:
Planctomycetes
,
Ca
. Atribacteria (OP9),
Ca
.
Armatimonadetes
(OP10),
Ca
. Latescibacteria (WS3),
Ca
. division (AC1),
Ca
. division (OP11), and
Ca
. Parcubacteria (OD1), which can be involved in hydrocarbon oxidation.
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EMUNI, FZAB, GEOZS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NUK, OILJ, PNG, SAZU, SBCE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We consider the Dirichlet problem for a second-order differential–difference equation in divergence form with variable coefficients on a finite interval
. Conditions on the right-hand side of the ...equation ensuring the smoothness of the generalized solution on the entire interval are studied. It is proved that the generalized solution of the problem belongs to the Sobolev space
if the right-hand side is orthogonal in the space
to finitely many linearly independent functions.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The Yakutsk Extensive Air Shower Array has been continuously operating for more than 50 years (since 1970) and up until recently it has been one of world’s largest ground-based instruments aimed at ...studying the properties of cosmic rays in the ultra-high energy domain. In this report we discuss results recently obtained at the array—on cosmic rays’ energy spectrum, mass composition and directional anisotropy—and how they fit into the world data. Special attention is paid to the measurements of muonic component of extensive air showers. Theoretical results of particle acceleration at shocks are also briefly reviewed. Future scientific and engineering plans on the array modernization are discussed.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, SIK, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We studied the effects of single and combined action of protons and carbon ions
12
C
6+
on the pool of MCF-7 human breast cancer stem cells. Single irradiation with a beam of protons or carbon ions ...had no significant effects on the relative number of cancer stem cells (CSC). The effects of combined irradiation in a total equieffective dose of 4 Gy depended on the sequence of exposure to ionizing radiations: the relative number of CSC did not change after irradiation with carbon ions and then with protons, but increased in the case of the reverse sequence. The most favorable result,
i.e
. a decrease in the CSC pool, was observed in the case of sequential irradiation with carbon ions and protons and their equal contribution to total equieffective dose. In this case, the absolute number of CSC decreased by on average 2.1 times in comparison with the control (
p
<0.05). The revealed regularities are of interest for the further development of new methods of radiation therapy.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The article discusses characteristics of a developed thermoelectric generator (TEG) based on an effect discovered by the authors concerning the change in the conductivity of a carbon fiber (CF) from ...electron (n-) to hole (p-) type following exposure to a pulsed current. A flexible TEG can be manufactured by combining CF and fiberglass fabric, in which the heat resistance of both materials ensures the creation of significant temperature gradients in the device. The results of an experimental study of this TEG are presented.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
We consider the second boundary-value problem for a second-order differential-difference equation with variable coefficients on the interval (0,
d
)
.
We investigate the existence of a generalized ...solution and obtain conditions on the right-hand side of the equation which ensure the smoothness of generalized solutions on the entire interval (0,
d
)
.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The preparation and identification of microstructure features as well as the texturing of the thermoelectric material Bi
2
Te
2.7
Se
0.3
doped with dysprosium are considered. The textured compounds ...Bi
2–
x
Dy
x
Te
2.7
Se
0.3
with
x
= 0.0000; 0.0010; 0.0025; 0.0050; 0.0100, and 0.0200 were obtained by means of solvothermal synthesis of the original powders and their subsequent spark plasma sintering. Dysprosium doping effects several interrelated phenomena. The first one is particle size reduction of the original powder with increasing
x
. This effect is explained by an increase in the ionicity of the covalently polar bonds Bi(Dy)–Te with increasing Dy content on account of the difference in the electro-negativity of Bi and Dy. The second effect is associated with average grain size reduction with increasing
x
in bulk samples, which is determined by a corresponding change in the particle size in the original powder with different amounts of alloying. This phenomenon also effects greater texturing in the samples.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
In this work we obtain and certify one-dimensional particles of the composition Bi2Te2.7Se0.3 of submicron size with an atypical growth direction. Further, the influence of the temperature of spark ...plasma sintering on the grain morphology and size, crystal-lattice parameters, elemental composition, and density of the samples obtained are investigated. The features of the formation of the crystallographic texture depending on the sintering temperature are also established. A temperature is revealed that allows for preservation of the crystal structure characteristic of the initial powder and materials with an atypical crystallographic texture to obtained. The thermoelectric properties of the materials obtained are also studied.
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