1,292 research outputs found
Multifractal analysis of stress time series during ultrathin lubricant film melting
Melting of an ultrathin lubricant film confined between two atomically flat
surfaces is we studied using the rheological model for viscoelastic matter
approximation. Phase diagram with domains, corresponding to sliding, dry, and
two types of friction regimes has been built taking into account
additive noises of stress, strain, and temperature of the lubricant. The stress
time series have been obtained for all regimes of friction using the
Stratonovich interpretation. It has been shown that self-similar regime of
lubricant melting is observed when intensity of temperature noise is much
larger than intensities of strain and stress noises. This regime is defined by
homogenous distribution, at which characteristic stress scale is absent. We
study stress time series obtained for all friction regimes using multifractal
detrended fluctuation analysis. It has been shown that multifractality of these
series is caused by different correlations that are present in the system and
also by a power-law distribution. Since the power-law distribution is related
to small stresses, this case corresponds to self-similar solid-like lubricant.Comment: 22 pages, 10 figures, 41 reference
The impact of innovations in the production of biologically valuable food products on supply chain management in the regional economy
Abstract— The article shows a study of the role of supply chain management of innovative biologically valuable food products in the industrial development and economy of the region. The analysis of the process of updating the assortment of food products based on the introduction of innovative developments and production principles conducive to the release of a healthy diet product (innovative product) is presented. The main provisions of the concept of healthy food products, the category of “innovative food products” are analyzed. The article systematizes the definitions of the concept of “innovative product”. Based on the results of the study, features, functional properties and characteristic features of an innovative food product are determined. Based on the concept of “innovative food product”, the concepts of “new food product”, “improved food product”, and “modified food product” are formulated. A classification model of innovative food products is presented. Based on it, it is shown that the development, production and sale of an innovative food product two functions: economic and social. The study made it possible to formulate the main criteria that make it possible to attribute a food product to a group of innovative food products. The article describes the characteristics of an innovative food product, describes market and consumer properties. The author's definitions of concepts are given: “innovative food product”, “new food product”, “improved food product”, “modified food product”. A classification of innovative food products is proposed
Properties of convective motions in facular regions
In this paper, we study the properties of solar granulation in a facular
region from the photosphere up to the lower chromosphere. Our aim is to
investigate the dependence of granular structure on magnetic field strength. We
use observations obtained at the German Vacuum Tower Telescope (Observatorio
del Teide, Tenerife) using two different instruments: Triple Etalon SOlar
Spectrometer (TESOS), in the BaII 4554 A line to measure velocity and intensity
variations along the photosphere; and, simultaneously, Tenerife Infrared
Polarimeter (TIP-II), in the FeI 1.56 m lines to the measure Stokes
parameters and the magnetic field strength at the lower photosphere. We obtain
that the convective velocities of granules in the facular area decrease with
magnetic field while the convective velocities of intergranular lanes increase
with the field strength. Similar to the quiet areas, there is a contrast and
velocity sign reversal taking place in the middle photosphere. The reversal
heights depend on the magnetic field strength and are, on average, about 100 km
higher than in the quiet regions. The correlation between convective velocity
and intensity decreases with magnetic field at the bottom photosphere, but
increases in the upper photosphere. The contrast of intergranular lanes
observed close to the disc center is almost independent of the magnetic field
strength. The strong magnetic field of facular area seems to stabilize the
convection and to promote more effective energy transfer in the upper layers of
the solar atmosphere, since the convective elements reach larger heights.Comment: accepted by Astronomy and Astrophysic
Features of spatial distribution of oscillations in faculae regions
We found that oscillations of LOS velocity in H-alpha are different for
various parts of faculae regions. Power spectra show that the contribution of
low-frequency modes (1.2 - 2 mHz) increase at the network boundaries. Three and
five- minute periods dominate inside cells. The spectra of photosphere and
chromosphere LOS velocity oscillations differ for most faculae. On the other
hand, we detected several cases where propagating oscillations in faculae were
manifest with a five-minute period. Their initiation point on spatial-temporal
diagrams coincided with the local maximum of the longitudinal magnetic field.Comment: 6 pages, 4 figure
Experimental investigation of animals survival adequacy and efficacy in case of their soft tissues gunshot wounds using the thermometry technique
The problem of gunshot wounds treatment is one of the urgent and incompletely
resolved issues of modern surgery. Diagnosis of gunshot wounds is currently not efficient
enough. There was a need to improve the content and scope of medical care with the
possibility of strengthening its diagnostic chain. The aim of the work is to substantiate
experimentally the feasibility and effectiveness of using diagnostic infrared thermometry in gunshot wounds of the soft tissues of the extremities. Experimental studies were performed
under the chronic experimental conditions on Shinshilla breed rabbits which were subjected to
gunshot wounds followed by laboratory, morphological and functional examination for 5
days. The animals were divided into 3 groups depending on the type of gunshot wound that
was inflicted. The animals were removed from the experiment by the introduction of
chloroethyl anesthesia on the 1st, 3rd and 5th days, after which the soft tissues with the capsule
surrounding the fragment were subjected to histological and electron microscopic
examination. On the 1st day of the study, a significant decrease in the diameter of the blood
vessels of the affected area was determined in the group of animals that were subject to injury
with firearms and metal fragments from the explosion of a grenade and an improvised
explosive device. It was in these groups that the highest mortality rate was registered. Under
the specified conditions of injury to the limbs of animals, as well as when injured by a
pneumatic weapon with a temperature of fragments of 100 oC, pronounced changes in pulse
and respiratory rate were noted. In further studies on rabbits on the 3rd and 5th days of the
experiment, the actual results did not differ from those obtained 24 hrs after injury. Those
rabbits that survived after the reproduction of various gunshot wounds had the greatest value.
The results of their thermometric measurements were evaluated in the dynamics of
experimental gunshot wounds and revealed the dependence of animal survival after gunshot
wounds on the temperature of the limb in the area of the wound.
There are the following leading criteria in favor of animals further survival after
gunshot wounds - the presence of a perforating vessel in the area surrounding the affected
space; the size of the diameter of the vessels in the adjacent area; no hemorrhage in the
muscle tissue located near the affected area; comparable with normal data of the functional
parameters of the animal's body – heart rate, blood oxygen pressure and respiration;
thermometry results. The limb thermometry has the important prognostic value after their
gunshot wound in terms of experimental animals survival. The correspondence of high
thermometry indexes after a gunshot wound vs the higher risk of an animal death is
statistically reliable and, accordingly, insignificant thermometric dynamics throughout the
experiment is in favor of a positive outcome after injury. It is extremely important to evaluate
thermometry data during the first 24 hours after receiving gunshot wounds, since we found
out the maximum validity of this method in the early time intervals. All this, with adequate
clinical testing and verification, has the most important medical prospects, aimed primarily at saving time for diagnostic measures and procedures. Thermometry allows to judge the activity and severity of connective tissue inflammation or sclerosis in the lesions of each
wound and provides the possibility of clinical application of remote thermography as a noninvasive method of diagnosis and prediction of complications in wounded with gunshot and explosives in various wounds
Simultaneous Proton Transfer Reaction-Mass Spectrometry and electronic nose study of the volatile compounds released by Plasmodium falciparum infected red blood cells in vitro
The discovery that Volatile Organic Compounds (VOCs) can be biomarkers for several diseases has led to the conception of their possible application as diagnostic tools. In this study, we aimed at defining of diagnostic signatures for the presence of malaria transmissible stages in infected individuals. To do this, we compared VOCs released by asexual and sexual stage cultures of Plasmodium falciparum, the deadliest species of malaria, with those emitted by uninfected red blood cells (RBCs). VOC analysis was carried out with an innovative set-up, where each sample was simultaneously analysed by proton transfer reaction time of flight mass spectrometry (PTR-ToF-MS) and an electronic nose. PTR-Tof-MS results show that sexual stages are characterized by a larger emission of hexanal, compared with uninfected or asexual stage-infected RBCs, which makes them clearly identifiable. PTR-Tof-MS analysis also detected differences in VOC composition between asexual stages and uninfected RBCs. These results have been substantially replicated by the electronic nose analysis and may open the possibility to develop sensitive and easy-to-use devices able to detect sexual parasite stages in infected individuals. This study also demonstrates that the combination of mass spectrometry with electronic noses is a useful tool to identify markers of diseases and to support the development of optimized sensors
Cell voltage versus electrode potential range in aqueous supercapacitors
Supercapacitors with aqueous electrolytes and nanostructured composite electrodes are attractive because of their high charging-discharging speed, long cycle life, low environmental impact and wide commercial affordability. However, the energy capacity of aqueous supercapacitors is limited by the electrochemical window of water. In this paper, a recently reported engineering strategy is further developed and demonstrated to correlate the maximum charging voltage of a supercapacitor with the capacitive potential ranges and the capacitance ratio of the two electrodes. Beyond the maximum charging voltage, a supercapacitor may still operate, but at the expense of a reduced cycle life. In addition, it is shown that the supercapacitor performance is strongly affected by the initial and zero charge potentials of the electrodes. Further, the differences are highlighted and elaborated between freshly prepared, aged under open circuit conditions, and cycled electrodes of composites of conducting polymers and carbon nanotubes. The first voltammetric charging-discharging cycle has an electrode conditioning effect to change the electrodes from their initial potentials to the potential of zero voltage, and reduce the irreversibility
Вплив попередників та строків сівби на врожайність сортів Triticum aestivum L. в умовах Центрального Лісостепу України
Мета. Визначити потенціал урожайності нових сортів пшениці озимої миронівської селекції залежно від попередників і строків сівби та встановити їх частки впливу в умовах Центрального Лісостепу України.
Методи. Дослідження проводили в польовому чотирифакторному досліді на базі Миронівського інституту пшениці імені В. М. Ремесла НААН упродовж 2018/19–2020/21 рр.
Результати. У результаті вивчення п’яти перспективних сортів пшениці озимої, висіяних 25 вересня та 05 жовтня після двох попередників (соя та соняшник), виявили, що незалежно від строків сівби середня врожайність для досліджуваних сортів після попередника соя була вищою і варіювала від 3,77 до 6,24 т/га у порівнянні з попередником соняшник – 3,35–5,52 т/га. Сорт ‘МІП Ювілейна’ сформував максимальну врожайність за першого строку сівби (5,52 та 6,24 т/га після попередників соняшник та соя відповідно), а сорт ‘МІП Фортуна’ – за другого (5,46 т/га після попередника соя).
Висновки. Установлено потенціал урожайності сортів пшениці озимої залежно від попередників та строків сівби в умовах Центрального Лісостепу України. За результатами дисперсійного аналізу отриманих даних з’ясовано частку впливу цих факторів на врожайність культури. Максимальний внесок у дисперсію врожайності був за роком висіву (67,8%) та попередником (20,9%)
Stokes Diagnostis of 2D MHD-simulated Solar Magnetogranulation
We study the properties of solar magnetic fields on scales less than the
spatial resolution of solar telescopes. A synthetic infrared
spectropolarimetric diagnostics based on a 2D MHD simulation of
magnetoconvection is used for this. We analyze two time sequences of snapshots
that likely represent two regions of the network fields with their immediate
surrounding on the solar surface with the unsigned magnetic flux density of 300
and 140 G. In the first region we find from probability density functions of
the magnetic field strength that the most probable field strength at logtau_5=0
is equal to 250 G. Weak fields (B < 500 G) occupy about 70% of the surface,
while stronger fields (B 1000 G) occupy only 9.7% of the surface. The magnetic
flux is -28 G and its imbalance is -0.04. In the second region, these
parameters are correspondingly equal to 150 G, 93.3 %, 0.3 %, -40 G, and -0.10.
We estimate the distribution of line-of-sight velocities on the surface of log
tau_5=-1. The mean velocity is equal to 0.4 km/s in the first simulated region.
The averaged velocity in the granules is -1.2 km/s and in the intergranules is
2.5 km/s. In the second region, the corresponding values of the mean velocities
are equal to 0, -1.8, 1.5 km/s. In addition we analyze the asymmetry of
synthetic Stokes-V profiles of the Fe I 1564.8 nm line. The mean values of the
amplitude and area asymmetry do not exceed 1%. The spatially smoothed amplitude
asymmetry is increased to 10% while the area asymmetry is only slightly varied.Comment: 24 pages, 12 figure
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