The paper presents the results of studying the extraction process in the technology of distilled drinks production at the stage of their aging with the use of oak chips, which reduces the duration of ...the technological process and reduces technological losses. At the engineering center "FOOD ENGINEERING" of Kemerovo State University, two extraction methods were selected for studying: 1) using a batch extractor for the "solid - liquid" system with exposure to oxygen, and 2) extraction based on the effects of microwave radiation. A comparative analysis of these processing methods has shown that the method of exposure to oxygen is more effective, taking into account the increase in optical density. The degree of oak chip charring was found to affect the color of the product significantly. Microwave radiation contributes to a more intensive accumulation of polyphenols, especially while using the chips with strong charring. When exposed to oxygen, the degree of charring had little influence on the content of polyphenols; still, exposure to oxygen intensified the process of phenolic compound extraction. The content of extractive solid compounds is higher in the samples exposed to oxygen and microwave radiation compared to the control sample, with little difference between different varieties of oak chips. In this regard, it has been planned to conduct further studies of the joint effect of these intensification methods on the extraction process.
We present an improved method for the precise reconstruction of cosmic-ray air showers above 1017 eV with sparse radio arrays. The method is based on the comparison of measured pulses to predictions ...for radio pulse shapes by CoREAS simulations. We applied our method to the data of Tunka-Rex, a 1 km2 radio array in Siberia operating in the frequency band of 30–80 MHz. Tunka-Rex is triggered by the air-Cherenkov detector Tunka-133 and by scintillators (Tunka-Grande). The instrument collects air-shower data since 2012. The present paper describes an updated data analysis of Tunka-Rex and details of the new method applied. After quality cuts, when Tunka-Rex reaches its full efficiency, the energy resolution of about 10% given by the new method has reached the limit of systematic uncertainties due to the calibration uncertainty and shower-to-shower fluctuations. At the same time the shower maximum reconstruction has improved compared to the previous method based on the slope of the lateral distribution and reaches a precision of better than 35 g/cm2. We also define conditions of the measurements at which the shower maximum resolution of Tunka-Rex reaches a value of 25 g/cm2 and becomes competitive to optical detectors. To check and validate our reconstruction and efficiency cuts we compare individual events to the reconstruction of Tunka-133. Furthermore, we compare the mean of the shower maximum as a function of primary energy to the measurements of other experiments.
Tunka-133: Results of 3 year operation Prosin, V.V.; Berezhnev, S.F.; Budnev, N.M. ...
Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment,
08/2014, Letnik:
756
Journal Article
Recenzirano
Odprti dostop
The EAS Cherenkov light array Tunka-133, with ~3km2 geometric area, is taking data since 2009. The array permits a detailed study of cosmic ray energy spectrum and mass composition in the PeV energy ...range. After a short description of the methods of EAS parameter reconstruction, we present the all-particle energy spectrum and results of studying CR composition, based on 3 seasons of array operation. In the last part of the paper, we discuss possible interpretations of the obtained results.
High-energy cosmic-ray research via the detection of Cherenkov radiation from extensive air showers was begun in the Tunka valley (50 km to the west from the southern extremity of Lake Baikal) in the ...early 1990s. A series of large arrays combined into the TAIGA (Tunka Advanced Instrument for cosmic-ray physics and Gamma Astronomy) astrophysical facility and designed to study gamma rays and charged cosmic rays have been created in the elapsed time. Descriptions of the facility arrays and the main results obtained while investigating high-energy cosmic rays are presented. Plans for a further development of the astrophysical facility are discussed.
A new analysis of the data from the NT200 neutrino telescope based on the reconstruction of parameters for high-energy showers generated in neutrino interactions has yielded new upper limits on the ...diffuse neutrino fluxes predicted by a number of theoreticalmodels. The upper limit on the all-flavor neutrino flux with an energy spectrum
E
−2
is
E
2
Φ
ν
< 2.9 × 10
−7
GeV cm
−2
s
−1
sr
−1
.
—
The paper is devoted to the modeling and analysis of data detected by the TAIGA-IACT installation in the stereo mode. Five Imaging Atmospheric Cherenkov Telescopes (IACT) with a viewing angle of ...9.6° are expected to be included in the installation. Today there are three telescopes spaced far apart (from 320 to 500 m) in the installation. The effective area of the installation is as large as 0.6 km
2
; therefore, it is possible to conduct statistically significant measurements of weak γ-ray sources in the energy range above 10 TeV over a reasonable observation time (300–400 h). The Monte Carlo procedure for simulating the hadrons and γ-rays detected by the telescopes is described as is the procedure for reconstructing the parameters of extensive air showers, such as the arrival direction of an event, the axis position, the depth of the maximum of shower development (
X
max
), and the primary-particle energy. In order to solve the problem of γ-hadron separation, the criteria for selecting γ-rays detected in the stereo mode have been optimized and the effective area of the installation has been calculated.
Various types of membrane units, including standard units for permeate separating, which are currently used for various liquids processing, are considered. Their advantages and disadvantages, working ...conditions and operating features are assessed. The principle of operation of membrane units with the bleed of the polarization layer is analyzed. A distinctive feature of such devices is the separation of the feed stream into three parts: adjacent to the membrane, including a polarization layer, with an increased concentration of high molecular substances (HMS) – concentrate, a spent stream core to be re-processed – retentate, and permeate, that practically contains no HMS. The unit scheme and the principle of operation of the plant completed with this equipment are given. A feature of this plant is the parallel arrangement of the membrane devices. In this configuration of the plant, there are two flow circulation loops and two tanks, in one of which there will be a depleted solution, in the other the retentate. During operation, the circulation of the depleted flow is provided. In this case, the resulting polarization layer (concentrate) will be discharged into the second tank. The working process continues until the complete depletion of the solution in the first tank. In the event that the solution in this tank is exhausted, and the required concentration of the product has not been reached, the second tank with the concentrate activates and the process continues. The principle of operation in this case is similar. The rotation of tanks continues until the required degree of concentration of the product is obtained. A calculation algorithm, a block diagram and a program for calculating the operating time of a membrane installation are proposed, for which a certificate of state registration of a computer program has been obtained. The calculation algorithm and program interface are presented. This program makes it possible to predict the operation of such installations and provides for the possibility of optimizing their operation.т.п.)
A wide-angle Cerenkov array TAIGA-HiSCORE (FOV
0.6 sr), was originally created as a part of TAIGA installation for high-energy gamma-ray astronomy and cosmic ray physics. Array now consist on nearly ...100 optical stations on the area of 1 km
. Due to high accuracy and stability (
1 ns) of time synchronization of the optical stations the accuracy of EAS arrival direction reconstruction is reached 0.1
. It was proven that the array can also be used to search for nanosecond events of the optical range. The report discusses the method of searching for optical transients using the HiSCORE array and demonstrates its performance on a real example of detecting signals from an artificial Earth satellite. The search for this short flares in the HiSCORE data of the winter season 2018–2019 is carried out. One candidate for double repeater has been detected, but the estimated probability of random simulation of such a transient by background EAS events is not less than 10
, which does not allow us to say that the detected candidate corresponds to a real astrophysical transient. An upper bound on the frequency of optical spikes with flux density of more than
and a duration of more than 5 ns is established as
events/sr/h.
TAIGA array addresses gamma-ray astronomy at energies from a few TeV to several PeV as well as cosmic ray physics from 100 TeV to several EeV. A 1 km2 TAIGA setup will consist of 120 wide-angle ...detectors of the Cherenkov timing array TAIGA-HiSCORE and three imaging air Cherenkov telescopes with the field of view diameter of 9.6°. In this paper, first experimental results of the first operation stage are presented: signal detection from two gamma-ray sources, the Crab Nebula and Markarian 421, by the first IACT in stand-alone mode. The detected signal is shown to be in agreement with the Monte Carlo expectation. In future, gamma-ray signal will be detected by a larger number of TAIGA telescopes as well as the TAIGA-HiSCORE array, that is, in combined operation mode.
The more correct recalculation from the measured Cherenkov light fluxes at distances of 200 (Q200) and 100 (Q100) m from the Extensive Air Shower (EAS) core to the energy of the primary particle has ...been developed using the results of M-C simulation by the CORSIKA code, assuming a light primary composition of cosmic rays. Using the new conversion expressions, a differential energy spectrum was obtained according to the data of the Tunka-133 array for 7 years of operation and the TAIGA-HiSCORE array for 2 years of operation.