1,805 research outputs found
Local redistribution of blood under the effect of fixation stress against a background of hypokinesia
Fixation stress was used as a model of emotional disturbance. The effect of previous restrictions on mobility on the local redistribution of blood resulting from fixation stress was examined. Disturbances in carbohydrate which result from prolonged hypokinesia was studied. Radioactivity was used to determine the local redistribution of blood. Modified factor analysis was used to study the results of the experiment
Breather Modes Induced by Localized RF Radiation: Analytical and Numerical Approaches
Numerical computations and collective variables approach are applied to analytical and numerical study of
spatially localized excitations of one-dimensional magnetic system in external high-frequency magnetic field. It
is demonstrated the hysteresis character of dependence for amplitude of local soliton-like states on external
field magnitude. The system shows a variety of interesting nonlinear phenomena such as periodicity doubling
and chaos
Cyclotrimerization of 3-R-1,2,4-triazin-5(4H)-ones with cyclic ketones
New heterocyclic tetracyclic systems were synthesized. Interaction between 3-R-1,2,4-triazin-5(4H)-ones and cyclic ketones under acidic conditions leads to the formation of zwitterion derivatives of 5,6,7,8,9,10,11,12-octahydro-[1,2,4] triazino[1,6- f ]phenanthridine and 1,2,3,6,7,8-hexahydro-bicyclopenta[b,d] pyrido[1,2- f ][1,2,4]triazine. © 2010 Verlag der Zeitschrift für Naturforschung, Tübingen
The connection between the radio jet and the gamma-ray emission in the radio galaxy 3C 120
We present the analysis of the radio jet evolution of the radio galaxy 3C 120
during a period of prolonged gamma-ray activity detected by the Fermi satellite
between December 2012 and October 2014. We find a clear connection between the
gamma-ray and radio emission, such that every period of gamma-ray activity is
accompanied by the flaring of the mm-VLBI core and subsequent ejection of a new
superluminal component. However, not all ejections of components are associated
with gamma-ray events detectable by Fermi. Clear gamma-ray detections are
obtained only when components are moving in a direction closer to our line of
sight.This suggests that the observed gamma-ray emission depends not only on
the interaction of moving components with the mm-VLBI core, but also on their
orientation with respect to the observer. Timing of the gamma-ray detections
and ejection of superluminal components locate the gamma-ray production to
within almost 0.13 pc from the mm-VLBI core, which was previously estimated to
lie about 0.24 pc from the central black hole. This corresponds to about twice
the estimated extension of the broad line region, limiting the external photon
field and therefore suggesting synchrotron self Compton as the most probable
mechanism for the production of the gamma-ray emission. Alternatively, the
interaction of components with the jet sheath can provide the necessary photon
field to produced the observed gamma-rays by Compton scattering.Comment: Already accepted for publication in The Astrophysical Journa
Determining the Young's modulus of a cellular titanium implant by FEM simulation
The role of additive manufacturing is noted for the construction of titanium medical implants. The purpose of the study is to determine the Young's modulus of cellular titanium implants, which is based on calculations performed by finite element analysis. A honeycomb structure from intersecting cylinder surfaces is offered for the implant made of the Ti-6Al-4V alloy. Boundary conditions are stated for the loading of the implant structure. It is demonstrated that the Young's modulus can be reduced more than three times comparing to a solid titanium alloy. Zones of strain and stress localization located near the abutment of the cylindrical surfaces. Recommendations for the further improvement of the implant architecture are generated. © 2017 Author(s).Ministry of Education and Science of the Russian Federation, Minobrnauka: 218We hereby acknowledge the support of the Ministry of Science and Education of the Russian Federation, in accordance with the decree of the Government of April 9, 2010, No. 218, project number 03.G25.31.0234
X-ray Diffraction Study of Superstructure in GdBaCo2O5.5
A single crystal of GdBaCo2O5.47(2) has been studied by means of X-ray
diffraction. Appearance of superstructure reflections at T = 341.5(7) K gives
an evidence of continuous transition to the phase with unit cell doubled along
the shortest edge a1. Critical exponent for the order parameter is found to be
beta=0.33(1). The superstructure reflections are about 2-4 orders of magnitude
weaker than the basic ones. Their systematic extinction indicates the crystal
symmetry change from Pmmm to Pmma. The integrated intensities allow to
calculate displacements of atoms from the positions in the high-temperature
phase. The cobalt-ligand distances in the ordered phase are discussed in terms
of the spin-state/orbital ordering of Co3+ ions.Comment: 4 page
Noble metal geochemistry of the Mesoproterozoic igneous complexes Bashkirian meganticlinorium and the eastern edge of the East European Platform
First described the noble metal (platinum group elements (PGE) and Au) geochemical specialization of magmatic rocks of Bashkirian meganticlinorium and the adjacent part of the East European Platform (EEP). Identity graphs of normalized PGE and Au contents in igneous rocks of the western slope of the Southern Urals and east EEP indicates the proximity of their formation and common mechanisms of formation of noble metal geochemical specialization during the formation of these bodies. It was found that the specific precious metal geochemical specialization (“rhodium anomaly”) magmatic complexes Bashkirian meganticlinorium and east EEP, due to the content of precious metals in sulphide minerals (pentlandite) has a “primary” nature. Variations contents Pt, Pd and Au, which are characteristic for different varieties of common species within the region, are the result of their redistribution during the formation of magmatic bodies and/or transformation by secondary processes. It is shown that the noble metal geochemical specialization of clastic rocks of Bashkirian meganticlinorium tectonic zones (presence of increased amounts of platinum and most importantly - “rhodium anomaly”) formed under the influence of magmatism with further redistribution and concentration of precious metals as a result of a later time metamorphism and local metasomatism
Interface-Induced Plasmon Nonhomogeneity in Nanostructured Metal-Dielectric Planar Metamaterial
Transformations of the electronic structure in thin silver layers in metal-dielectric (TiAlN/Ag) multilayer nanocomposite were investigated by a set of electron spectroscopy techniques. Localization of the electronic states in the valence band and reduction of electron concentration in the conduction band was observed. This led to decreasing metallic properties of silver in the thin films. A critical layer thickness of 23.5 nm associated with the development of quantum effects was determined by X-ray photoelectron spectroscopy. Scanning Auger electron microscopy of characteristic energy losses provided images of plasmon localization in the Ag layers. The nonuniformity of plasmon intensities distribution near the metal-nitride interfaces was assessed experimentally
Sub-milliarcsecond Imaging of Quasars and Active Galactic Nuclei. IV. Fine Scale Structure
We have used VLBA fringe visibility data obtained at 15 GHz to examine the
compact structure in 250 extragalactic radio sources. For 171 sources in our
sample, more than half of the total flux density seen by the VLBA remains
unresolved on the longest baselines. There are 163 sources in our list with a
median correlated flux density at 15 GHz in excess of 0.5 Jy on the longest
baselines. For about 60% of the sources, we have at least one observation in
which the core component appears unresolved (generally smaller than 0.05 mas)
in one direction, usually transverse to the direction into which the jet
extends. BL Lacs are on average more compact than quasars, while active
galaxies are on average less compact. Also, in an active galaxy the
sub-milliarcsecond core component tends to be less dominant. IDV sources
typically have a more compact, more core-dominated structure on
sub-milliarcsecond scales than non-IDV sources, and sources with a greater
amplitude of intra-day variations tend to have a greater unresolved VLBA flux
density. The objects known to be GeV gamma-ray loud appear to have a more
compact VLBA structure than the other sources in our sample. This suggests that
the mechanisms for the production of gamma-ray emission and for the generation
of compact radio synchrotron emitting features are related. The brightness
temperature estimates and lower limits for the cores in our sample typically
range between 10^11 and 10^13 K, but they extend up to 5x10^13 K, apparently in
excess of the equipartition brightness temperature, or the inverse Compton
limit for stationary synchrotron sources. The largest component speeds are
observed in radio sources with high observed brightness temperatures, as would
be expected from relativistic beaming (abridged).Comment: 31 pages, 13 figures, 4 tables, accepted for publication in the
Astronomical Journal; minor changes to the text are mad
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