277 research outputs found
Star formation in the S233 region
The main objective of this paper is to study the possibility of triggered
star formation on the border of the HII region S233, which is formed by a
B-star. Using high-resolution spectra we determine the spectral class of the
ionizing star as B0.5 V and the radial velocity of the star to be -17.5(1.4)
km/s. This value is consistent with the velocity of gas in a wide field across
the S233 region, suggesting that the ionizing star was formed from a parent
cloud belonging to the S233 region. By studying spatial-kinematic structure of
the molecular cloud in the S233 region, we detected an isolated clump of gas
producing CO emission red-shifted relative to the parent cloud. In the UKIDSS
and WISE images, the clump of gas coincides with the infrared source containing
a compact object and bright-rimmed structure. The bright-rimmed structure is
perpendicular to the direction of the ionizing star. The compact source
coincides in position with IRAS source 05351+3549. All these features indicate
a possibility of triggering formation of a next-generation star in the S233
region. Within the framework of a theoretical one-dimensional model we conclude
that the "collect-and-collapse" process is not likely to take place in the S233
region. The presence of the bright-rimmed structure and the compact infrared
source suggest that the "collapse of the pre-existing clump" process is taking
place.Comment: 12 pages, 10 figure
Prediction of physical-chemical and fire hazard characteristics by carbon chain rules. 2. Carboxylic acids
Investigation of the dependence of physico-chemical and fire hazard properties from the chemical structure of carboxylic acids is carried out. Forecasting of the boiling temperature, the flash point, the temperature and the concentration flammability limits, the heats of combustion and vaporization is performed by the carbon chain rules (CCR). The following empirical equations for the calculation of physico-chemical and fire hazard indices from the conventional carbon chain and from the number of carbon atoms are proposed for the convenience of practical application of the CCR. A comparative analysis of the proposed methods for the flash point calculating and the already known methods of GOST 12.1.044-89, Mendeleev and ACD/Lab 2014 is carried out. It is shown, basically, that the new methods give more accurate calculation results than the comparison design procedures. © Siberian Federal University. All rights reserve
Use of Internet Space in Advertising on the Example of the Trademark “Rastishka”
В современную эпоху основной площадкой для передачи информации становится глобальная сеть Интернет. В настоящее время Интернет активно развивает и показывает себя в качестве действительно доступного практически каждому рекламного канала. В данной статье мы проанализируем использование интернет-пространства в рекламе, а также способы ее распространения в Сети на примере торговой марки «Растишка».In the era of modernity, the main network for transmitting information is becoming the global Internet. Available to almost every ad channel. In this scientific article, we analyzed the use of Internet space in advertising, as well as distribution methods on the network using the example of the “Rastishka” trademark
Quantum squeezing of optical dissipative structures
We show that any optical dissipative structure supported by degenerate
optical parametric oscillators contains a special transverse mode that is free
from quantum fluctuations when measured in a balanced homodyne detection
experiment. The phenomenon is not critical as it is independent of the system
parameters and, in particular, of the existence of bifurcations. This result is
a consequence of the spatial symmetry breaking introduced by the dissipative
structure. Effects that could degrade the squeezing level are considered.Comment: 4 pages and a half, 1 fugure. Version to appear in Europhysics
Letter
Stability analysis of static solutions in a Josephson junction
We present all the possible solutions of a Josephson junction with bias
current and magnetic field with both inline and overlap geometry, and examine
their stability. We follow the bifurcation of new solutions as we increase the
junction length. The analytical results, in terms of elliptic functions in the
case of inline geometry, are in agreement with the numerical calculations and
explain the strong hysteretic phenomena typically seen in the calculation of
the maximum tunneling current. This suggests a different experimental approach
based on the use, instead of the external magnetic field the modulus of the
elliptic function or the related quantity the total magnetic flux to avoid
hysteretic behavior and unfold the overlapping curves.Comment: 36 pages with 17 figure
Two and three-dimensional oscillons in nonlinear Faraday resonance
We study 2D and 3D localised oscillating patterns in a simple model system
exhibiting nonlinear Faraday resonance. The corresponding amplitude equation is
shown to have exact soliton solutions which are found to be always unstable in
3D. On the contrary, the 2D solitons are shown to be stable in a certain
parameter range; hence the damping and parametric driving are capable of
suppressing the nonlinear blowup and dispersive decay of solitons in two
dimensions. The negative feedback loop occurs via the enslaving of the
soliton's phase, coupled to the driver, to its amplitude and width.Comment: 4 pages; 1 figur
Impurity-induced stabilization of solitons in arrays of parametrically driven nonlinear oscillators
Chains of parametrically driven, damped pendula are known to support
soliton-like clusters of in-phase motion which become unstable and seed
spatiotemporal chaos for sufficiently large driving amplitudes. We show that
the pinning of the soliton on a "long" impurity (a longer pendulum) expands
dramatically its stability region whereas "short" defects simply repel solitons
producing effective partition of the chain. We also show that defects may
spontaneously nucleate solitons.Comment: 4 pages in RevTeX; 7 figures in ps forma
Multistable Pulse-like Solutions in a Parametrically Driven Ginzburg-Landau Equation
It is well known that pulse-like solutions of the cubic complex
Ginzburg-Landau equation are unstable but can be stabilised by the addition of
quintic terms. In this paper we explore an alternative mechanism where the role
of the stabilising agent is played by the parametric driver. Our analysis is
based on the numerical continuation of solutions in one of the parameters of
the Ginzburg-Landau equation (the diffusion coefficient ), starting from the
nonlinear Schr\"odinger limit (for which ). The continuation generates,
recursively, a sequence of coexisting stable solutions with increasing number
of humps. The sequence "converges" to a long pulse which can be interpreted as
a bound state of two fronts with opposite polarities.Comment: 13 pages, 6 figures; to appear in PR
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