5,959 research outputs found
Development of the New Point Scale of Organoleptic Evaluation at Manufacturing Organic Cakes
The article presents the ground of developing the 50-point scale for evaluating cakes by organoleptic parameters. The aim of the article is to create the new point scale of organoleptic evaluation for using at producing organic cakes. It was established, that for today such important parameters as “flavor”, “post-flavor”, “porosity structure” are not always used at the organoleptic evaluation of cakes' quality. The article describes the recipes of four developed cakes, produced of the organic raw materials – “Grechanyk”, based on buckwheat flour, “Zhytnytsa', based on rye flour, “Golden amaranth”, based on amaranth flour and “Hempen delight”, based on hempen flour. For evaluating organoleptic characteristics of cakes, there was presented 50-point scale that includes evaluation of the following parameters: form, surface condition, color of crust, condition and color of crumble, porosity structure, smell, taste, flavor, post-taste, malaxation of crumble. Based on the method of expert evaluations, there were determined significance coefficients for each parameter. Thus, coefficient 0,5 was set for the parameters “porosity structure” and 1,5 for “color” and “smell”, the significance coefficient was equal 1 for a series of other parameters. The developed scale provided the following criteria of cakes evaluation: 45–50 points − "perfectly”, 40–44 points − "well", 30–39 points − "satisfactorily”, lower 30 points – “unsatisfactorily”. Based on the developed scale, the developed cakes were evaluated by the gustatory commission. All developed cakes corresponded to the mark “perfectly” by organoleptic parameters. The highest index of the quality level was inherent to the cake “Grechanyk” " – 0,99 at general sum of points for the gustatory evaluation 49,95. The cake Zhytnytsa corresponded to 0,98 by the quality level, "Hempen delight" – 0,96. The lowest quality level was detected in the cake “Golden amaranth” (0,94),that is caused by the specific taste of amaranth flour
Probing high-mass stellar evolutionary models with binary stars
Mass discrepancy is one of the problems that is pending a solution in
(massive) binary star research field. The problem is often solved by
introducing an additional near core mixing into evolutionary models, which
brings theoretical masses of individual stellar components into an agreement
with the dynamical ones. In the present study, we perform a detailed analysis
of two massive binary systems, V380 Cyg and Sigma Sco, to provide an
independent, asteroseismic measurement of the overshoot parameter, and to test
state-of-the-art stellar evolution models.Comment: 5 pages, 1 figure, 3 tables; proceedings of the IAU Symposium 307
held in Geneva in June 201
Tkachenko modes as sources of quasiperiodic pulsar spin variations
We study the long wavelength shear modes (Tkachenko waves) of triangular
lattices of singly quantized vortices in neutron star interiors taking into
account the mutual friction between the superfluid and the normal fluid and the
shear viscosity of the normal fluid. The set of Tkachenko modes that propagate
in the plane orthogonal to the spin vector are weakly damped if the coupling
between the superfluid and normal fluid is small. In strong coupling, their
oscillation frequencies are lower and are undamped for small and moderate shear
viscosities. The periods of these modes are consistent with the observed
~100-1000 day variations in spin of PSR 1828-11.Comment: 7 pages, 3 figures, uses RevTex, v2: added discussion/references,
matches published versio
Modelling of the B-type binaries CW Cep and U Oph: A critical view on dynamical masses, core boundary mixing, and core mass
Context: Intermediate-Mass stars are often overlooked as they are not
supernova progenitors but still host convective cores and complex atmospheres
which require computationally expensive treatment. Due to this, there is a
general lack of such stars modelled by state of the art stellar structure and
evolution codes. Aims: This paper aims to use high-quality spectroscopy to
update the dynamically obtained stellar parameters and produce a new
evolutionary assessment of the bright B0.5+B0.5 and B5V+B5V binary systems CW
Cep and U Oph. Methods: We use new spectroscopy obtained with the Hermes
spectrograph to revisit the photometric binary solution of the two systems. The
updated mass ratio and effective temperatures are incorporated to obtain new
dynamical masses for the primary and secondary. With these, we perform
isochrone-cloud based evolutionary modelling to investigate the core properties
of these stars. Results: We report the first abundances for CW Cep and U Oph as
well as report an updated dynamical solution for both systems. We find that we
cannot uniquely constrain the amount of core boundary mixing in any of the
stars we consider. Instead, we report their core masses and compare our results
to previous studies. Conclusions: We find that the per-cent level precision on
fundamental stellar quantities are accompanied with core mass estimates to
between ~ 5-15%. We find that differences in analysis techniques can lead to
substantially different evolutionary modeComment: 15 pages, 7 figures, two appendices with 4 figures each. Accepted for
publication in Astronomy & Astrophysic
The interior angular momentum of core hydrogen burning stars from gravity-mode oscillations
A major uncertainty in the theory of stellar evolution is the angular
momentum distribution inside stars and its change during stellar life. We
compose a sample of 67 stars in the core-hydrogen burning phase with a
value from high-resolution spectroscopy, as well as an asteroseismic
estimate of the near-core rotation rate derived from gravity-mode oscillations
detected in space photometry. This assembly includes 8 B-type stars and 59
AF-type stars, covering a mass range from 1.4 to 5\,M, i.e., it
concerns intermediate-mass stars born with a well-developed convective core.
The sample covers projected surface rotation velocities km\,s and core rotation rates up to Hz, which
corresponds to 50\% of the critical rotation frequency. We find deviations from
rigid rotation to be moderate in the single stars of this sample. We place the
near-core rotation rates in an evolutionary context and find that the core
rotation must drop drastically before or during the short phase between the end
of the core-hydrogen burning and the onset of core-helium burning. We compute
the spin parameter, which is the ratio of twice the rotation rate to the mode
frequency (also known as the inverse Rossby number), for 1682 gravity modes and
find the majority (95\%) to occur in the sub-inertial regime. The ten stars
with Rossby modes have spin parameters between 14 and 30, while the
gravito-inertial modes cover the range from 1 to 15.Comment: Manuscript of 5 pages, including 2 figures, accepted for publication
in The Astrophysical Journal Letter
Giant Vortex Lattice Deformations in Rapidly Rotating Bose-Einstein Condensates
We have performed numerical simulations of giant vortex structures in rapidly
rotating Bose-Einstein condensates within the Gross-Pitaevskii formalism. We
reproduce the qualitative features, such as oscillation of the giant vortex
core area, formation of toroidal density hole, and the precession of giant
vortices, observed in the recent experiment [Engels \emph{et.al.}, Phys. Rev.
Lett. {\bf 90}, 170405 (2003)]. We provide a mechanism which quantitatively
explains the observed core oscillation phenomenon. We demonstrate the clear
distinction between the mechanism of atom removal and a repulsive pinning
potential in creating giant vortices. In addition, we have been able to
simulate the transverse Tkachenko vortex lattice vibrations.Comment: 5 pages, 6 figures; revised description of core oscillation, new
subfigur
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