3,649 research outputs found
Covariant Treatment of Neutrino Spin (Flavour) Conversion in Matter under the Influence of Electromagnetic Fields
Within the recently proposed Lorentz invariant formalism for description of
neutrino spin evolution in presence of an arbitrary electromagnetic fields
effects of matter motion and polarization are considered.Comment: Extended version of contribution to "Particle Physics on Boundary of
Millenniums" (Proceedings of the 9th Lomonosov Conference on Elementary
Particle Physics, World Scientific, Singapure
MODELING OF ADS-B MESSAGES TRANSMISSION VIA IRIDIUM SATELLITES COMMUNICATION CHANNEL
In this article the idea of ADS-B message transmission via communication channel by means of Iridium satellites was considered. The transmission model based on real parameters was created and investigated
Multi-frequency investigation of the parsec- and kilo-parsec-scale radio structures in high-redshift quasar PKS 1402+044
We investigate the frequency-dependent radio properties of the jet of the
luminous high-redshift (z = 3.2) radio quasar PKS 1402+044 (J1405+0415) by
means of radio interferometric observations. The observational data were
obtained with the VLBI Space Observatory Programme (VSOP) at 1.6 and 5 GHz,
supplemented by other multi-frequency observations with the Very Long Baseline
Array (VLBA; 2.3, 8.4, and 15 GHz) and the Very Large Array (VLA; 1.4, 5, 15,
and 43 GHz). The observations span a period of 7 years. We find that the
luminous high-redshift quasar PKS 1402+044 has a pronounced "core-jet"
morphology from the parsec to the kilo-parsec scales. The jet shows a steeper
spectral index and lower brightness temperature with increasing distance from
the jet core. The variation of brightness temperature agrees well with the
shock-in-jet model. Assuming that the jet is collimated by the ambient magnetic
field, we estimate the mass of the central object as ~10^9 M_sun. The upper
limit of the jet proper motion of PKS 1402+044 is 0.03 mas/yr (~3c) in the
east-west direction.Comment: 9 pages, 6 figures
Extragalactic Relativistic Jets and Nuclear Regions in Galaxies
Past years have brought an increasingly wider recognition of the ubiquity of
relativistic outflows (jets) in galactic nuclei, which has turned jets into an
effective tool for investigating the physics of nuclear regions in galaxies. A
brief summary is given here of recent results from studies of jets and nuclear
regions in several active galaxies with prominent outflows.Comment: 5 pages; contribution to ESO Astrophysical Symposia, "Relativistic
Astrophysics and Cosmology", eds. B. Aschenbach, V. Burwitz, G. Hasinger, B.
Leibundgut (Springer: Heidelberg 2006
Statistical evaluation of the effect of hygrothermal aging on the interlaminar shear of GFRP
ΠΠ·ΡΡΠ΅Π½ΠΈΠ΅ Π·Π°ΠΊΠΎΠ½ΠΎΠΌΠ΅ΡΠ½ΠΎΡΡΠ΅ΠΉ ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΡ ΡΠ²ΠΎΠΉΡΡΠ², Π½Π°ΠΊΠΎΠΏΠ»Π΅Π½ΠΈΡ ΠΏΠΎΠ²ΡΠ΅ΠΆΠ΄Π΅Π½ΠΈΠΉ ΠΈ ΡΠ°Π·ΡΡΡΠ΅Π½ΠΈΡ ΠΊΠΎΠ½ΡΡΡΡΠΊΡΠΈΠΎΠ½Π½ΡΡ
ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠΎΠ² ΠΏΠΎΡΠ»Π΅ Π³ΠΈΠ³ΡΠΎΡΠ΅ΡΠΌΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ ΡΡΠ°ΡΠ΅Π½ΠΈΡ ΠΏΡΠ΅Π΄ΡΡΠ°Π²Π»ΡΠ΅Ρ ΡΠΎΠ±ΠΎΠΉ Π°ΠΊΡΡΠ°Π»ΡΠ½ΠΎΠ΅ ΠΈ Π²Π°ΠΆΠ½ΠΎΠ΅ Π½Π°ΠΏΡΠ°Π²Π»Π΅Π½ΠΈΠ΅. Π ΡΠ°Π±ΠΎΡΠ΅ ΠΏΡΠ΅Π΄ΡΡΠ°Π²Π»Π΅Π½Ρ ΡΠ΅Π·ΡΠ»ΡΡΠ°ΡΡ ΠΌΠ΅Ρ
Π°Π½ΠΈΡΠ΅ΡΠΊΠΈΡ
ΠΈΡΠΏΡΡΠ°Π½ΠΈΠΉ Π½Π° ΠΌΠ΅ΠΆΡΠ»ΠΎΠΉΠ½ΡΠΉ ΡΠ΄Π²ΠΈΠ³ ΠΎΠ±ΡΠ°Π·ΡΠΎΠ² ΡΠ»Π΅ΠΊΡΡΠΎΡΠ΅Ρ
Π½ΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ ΠΊΠΎΠ½ΡΡΡΡΠΊΡΠΈΠΎΠ½Π½ΠΎΠ³ΠΎ ΡΡΠ΅ΠΊΠ»ΠΎΠΏΠ»Π°ΡΡΠΈΠΊΠ° ΠΈ ΡΠΏΠΎΠΊΡΠΈΠ΄Π½ΠΎΠ³ΠΎ ΠΊΠΎΠΌΠΏΠΎΠ·ΠΈΡΠ° Π΄ΠΎ ΠΈ ΠΏΠΎΡΠ»Π΅ ΠΏΡΠ΅Π΄Π²Π°ΡΠΈΡΠ΅Π»ΡΠ½ΠΎΠ³ΠΎ Π³ΠΈΠ³ΡΠΎΡΠ΅ΡΠΌΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ ΡΡΠ°ΡΠ΅Π½ΠΈΡ Π² ΡΠ°Π±ΠΎΡΠΈΡ
ΡΡΠ΅Π΄Π°Ρ
(ΡΠ΅Ρ
Π½ΠΈΡΠ΅ΡΠΊΠ°Ρ Π²ΠΎΠ΄Π°, ΠΌΠΎΡΡΠΊΠ°Ρ Π²ΠΎΠ΄Π°, ΠΌΠ°ΡΠΈΠ½Π½ΠΎΠ΅ ΠΌΠ°ΡΠ»ΠΎ) ΡΠ°Π·Π»ΠΈΡΠ½ΠΎΠΉ ΠΏΡΠΎΠ΄ΠΎΠ»ΠΆΠΈΡΠ΅Π»ΡΠ½ΠΎΡΡΠΈ (15, 30 ΠΈ 45 ΡΡΡΠΎΠΊ. ) ΠΈ ΡΠ°Π·Π»ΠΈΡΠ½ΡΡ
ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡ (22, 60 ΠΈ 90ΒΊΠ‘). Π Π΅Π·ΡΠ»ΡΡΠ°ΡΡ ΠΈΡΠΏΡΡΠ°Π½ΠΈΠΉ Π±ΡΠ»ΠΈ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½Ρ Π΄Π»Ρ ΡΡΠ°ΡΠΈΡΡΠΈΡΠ΅ΡΠΊΠΎΠΉ ΠΎΡΠ΅Π½ΠΊΠΈ Π·Π½Π°ΡΠΈΠΌΠΎΡΡΠΈ Π½Π΅ΠΌΠΎΠ½ΠΎΡΠΎΠ½Π½ΡΡ
ΠΈΠ·ΠΌΠ΅Π½Π΅Π½ΠΈΠΉ ΠΏΡΠΎΡΠ½ΠΎΡΡΠΈ Π² ΡΠ»ΡΡΠ°Π΅ ΠΌΠ΅ΠΆΡΠ»ΠΎΠΉΠ½ΠΎΠ³ΠΎ ΡΠ΄Π²ΠΈΠ³Π° ΠΏΠΎΡΠ»Π΅ ΠΏΡΠ΅Π΄Π²Π°ΡΠΈΡΠ΅Π»ΡΠ½ΠΎΠ³ΠΎ Π³ΠΈΠ³ΡΠΎΡΠ΅ΡΠΌΠΈΡΠ΅ΡΠΊΠΎΠ³ΠΎ ΡΡΠ°ΡΠ΅Π½ΠΈΡ ΠΎΡΠ½ΠΎΡΠΈΡΠ΅Π»ΡΠ½ΠΎ Π½ΠΎΠΌΠΈΠ½Π°Π»ΡΠ½ΠΎΠ³ΠΎ ΠΌΠ°ΡΠ΅ΡΠΈΠ°Π»Π° Ρ ΠΈΡΠΏΠΎΠ»ΡΠ·ΠΎΠ²Π°Π½ΠΈΠ΅ΠΌ ANCOVA ΠΈ ΡΠ΅Π³ΡΠ΅ΡΡΠΈΠΎΠ½Π½ΠΎΠ³ΠΎ Π°Π½Π°Π»ΠΈΠ·Π°. Π’Π°ΠΊΠΈΠ΅ ΠΌΠ΅ΡΠΎΠ΄Ρ ΠΏΠΎΠΊΠ°Π·Π°Π»ΠΈ, ΡΡΠΎ ΠΌΠΎΡΡΠΊΠΈΠ΅ ΠΈ ΡΠ΅Ρ
Π½ΠΎΠ»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΈΠ΅ Π²ΠΎΠ΄Π½ΡΠ΅ ΡΠ°ΡΡΠ²ΠΎΡΡ ΠΎΡΡΠΈΡΠ°ΡΠ΅Π»ΡΠ½ΠΎ Π²Π»ΠΈΡΡΡ Π½Π° ΠΏΡΠΎΡΠ½ΠΎΡΡΡ Π½Π° ΠΌΠ΅ΠΆΡΠ»ΠΎΠΉΠ½ΡΠΉ ΡΠ΄Π²ΠΈΠ³, Π½ΠΎ ΠΈΡ
Π²Π»ΠΈΡΠ½ΠΈΠ΅ Π±ΡΠ»ΠΎ Π½Π΅ΠΌΠ½ΠΎΠ³ΠΎ ΡΠ°Π·Π»ΠΈΡΠ½ΡΠΌ ΠΈ ΡΠΈΠ»ΡΠ½ΠΎ Π·Π°Π²ΠΈΡΠ΅Π»ΠΎ ΠΎΡ ΡΡΡΠ΅ΠΊΡΠ° Π²Π·Π°ΠΈΠΌΠΎΠ΄Π΅ΠΉΡΡΠ²ΠΈΡ ΠΌΠ΅ΠΆΠ΄Ρ Π²ΡΠ΅ΠΌΠ΅Π½Π΅ΠΌ Π²ΠΎΠ·Π΄Π΅ΠΉΡΡΠ²ΠΈΡ ΠΈ ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΠΎΠΉ ΡΠ°ΡΡΠ²ΠΎΡΠ°. Π’Π°ΠΊΠΈΠΌ ΠΎΠ±ΡΠ°Π·ΠΎΠΌ, ΠΌΠ°ΠΊΡΠΈΠΌΠ°Π»ΡΠ½Π°Ρ ΡΠ°Π·Π½ΠΈΡΠ° ΡΠΎΡΡΠ°Π²Π»ΡΠ΅Ρ ΠΎΠΊΠΎΠ»ΠΎ 15% ΠΈ 12% ΠΏΠΎΡΠ»Π΅ 45 Π΄Π½Π΅ΠΉ Π²Π½ΡΡΡΠΈ ΡΠ΅Ρ
Π½ΠΎΠ»ΠΎΠ³ΠΈΡΠ΅ΡΠΊΠΎΠΉ ΠΈ ΠΌΠΎΡΡΠΊΠΎΠΉ Π²ΠΎΠ΄Ρ ΠΏΡΠΈ ΡΠ΅ΠΌΠΏΠ΅ΡΠ°ΡΡΡΠ΅ 90 ΒΊC ΡΠΎΠΎΡΠ²Π΅ΡΡΡΠ²Π΅Π½Π½ΠΎ. ΠΠ°ΠΏΡΠΎΡΠΈΠ², Π²ΠΎΠ·Π΄Π΅ΠΉΡΡΠ²ΠΈΠ΅ ΠΌΠ°ΡΠΈΠ½Π½ΠΎΠ³ΠΎ ΠΌΠ°ΡΠ»Π° ΠΏΡΠΈΠ²Π΅Π»ΠΎ ΠΊ ΡΠ²Π΅Π»ΠΈΡΠ΅Π½ΠΈΡ ΠΏΡΠΎΡΠ½ΠΎΡΡΠΈ, Π½ΠΎ ΡΡΡΠ΅ΠΊΡ Π±ΠΎΠ»Π΅Π΅ ΡΠ»Π°Π±ΡΠΉ ΠΏΠΎ ΡΡΠ°Π²Π½Π΅Π½ΠΈΡ Ρ Π²ΠΎΠ΄Π½ΡΠΌΠΈ ΡΠ°ΡΡΠ²ΠΎΡΠ°ΠΌΠΈ (ΠΎΠΊΠΎΠ»ΠΎ 6%)
Practical analytical solutions for benchmarking of 2-D and 3-D geodynamic Stokes problems with variable viscosity
Geodynamic modeling is often related with challenging computations
involving solution of the Stokes and continuity equations under
the condition of highly variable viscosity. Based on a new analytical
approach we have developed particular analytical solutions for 2-D and
3-D incompressible Stokes flows with both linearly and exponentially
variable viscosity. We demonstrate how these particular solutions
can be converted into 2-D and 3-D test problems suitable for
benchmarking numerical codes aimed at modeling various mantle
convection and lithospheric dynamics problems. The Main advantage of
this new generalized approach is that a large variety of benchmark
solutions can be generated, including relatively complex cases with
open model boundaries, non-vertical gravity and variable gradients
of the viscosity and density fields, which are not parallel to the Cartesian
axes. Examples of respective 2-D and 3-D MatLab codes are provided
with this paper
VSOP observation of the quasar PKS 2215+020: a new laboratory for core-jet physics at z=3.572
We report results of a VSOP (VLBI Space Observatory Programme) observation of
a high redshift quasar PKS 2215+020 (z=3.572). The ~1 milliarcsecond resolution
image of the quasar reveals a prominent `core-jet' structure on linear scales
from 5/h to 300/h pc ($H_0=100*h km/(s*Mpc). The brightness temperatures and
sizes of bright features identified in the jet are consistent with emission
from relativistic shocks dominated by adiabatic energy losses. The jet is
powered by the central black hole with estimated mass of ~4*10^9 solar masses.
Comparisons with VLA and ROSAT observations indicate a possible presence of an
extended radio/X-ray halo surrounding 2215+020.Comment: 15 pages, 6 figures, aastex macros; accepted for publication in The
Astrophysical Journal, V.546, N.2 *(January 10 2001
Mechanochemical conversion of acetylene in quartz β ultrafine metal powder system
We have studied the effect of nano-sized metal powders (Zn, Ni), obtained by electric explosion of wires, on mechanochemical conversions of acetylene in the presence of quartz. In the process of acetylene mechanical treatment (MT) in the presence of quartz, benzene is formed. During the mechanical grinding of quartz in planetary-centrifugal mills, active radical sites are formed on quartz surface. It is possible to suppose that due to the influence of mechanical energy acetylene triple bond breaks to form ethyl radicals, which are subjected to chemosorption on active quartz sites with subsequent formation of benzene. The addition of ultrafine Zn powder decreased, while Ni powder considerably increased benzene yield. In the process of MT, particles of ultrafine Zn powder are agglomerated which results in the decrease of its catalytic activity. The increase in benzene yield at the use of ultrafine Ni powder as the additives is associated with catalytic conversion of acetylene into benzene on the newly formed nickel surface. The injection of ultrafine Zn and Ni powders in quartz-acetylene system caused no changes in quantitative composition of acetylene conversion products but affected the amounts of one or other component formation
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