Reprocessing of spent nuclear fuel (SNF) is an important task in a frame of ecology and rational use of natural resources. Uranium, as the main component of SNF (>95%), can be recovered for further ...use as fresh nuclear fuel. To minimize an amount of solid radioactive waste generated during SNF reprocessing, new extractants are under investigation. Diamides of 1,10-phenanthroline-2,9-dicarboxylic acid are perspective tetradentate N-donor ligands that form strong complexes with f-elements, which are soluble in polar organic solvents. As an example of three ligands of this class, we conducted a comparative study and showed how the substituent in the amide functional group affects the extraction ability toward uranyl nitrate from nitric acid media. We have performed a careful study (NMR, FT-IR, XRD, RMC-EXAFS) of the structures of synthesized complexes of new ligands with uranyl nitrate and used quantum mechanical calculations to explain the discovered regularities through.
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IJS, KILJ, NUK, PNG, UL, UM
Gut microbiota of patients with Parkinson’s disease and healthy volunteers was analyzed by the method of high throughput 16S rRNA sequencing of bacterial genomes. In patients with Parkinson’s ...diseases, changes in the content of 9 genera and 15 species of microorganisms were revealed: reduced content of
Dorea
,
Bacteroides
,
Prevotella
,
Faecalibacterium
,
Bacteroides massiliensis
,
Stoquefichus massiliensis
,
Bacteroides coprocola
,
Blautia glucerasea
,
Dorea longicatena
,
Bacteroides dorei
,
Bacteroides plebeus
,
Prevotella copri
,
Coprococcus eutactus
, and
Ruminococcus callidus
, and increased content of
Christensenella
,
Catabacter
,
Lactobacillus
,
Oscillospira
,
Bifidobacterium
,
Christensenella minuta
,
Catabacter hongkongensis
,
Lactobacillus mucosae
,
Ruminococcus bromii
, and
Papillibacter cinnamivorans
. This microbiological pattern of gut microflora can trigger local inflammation followed by aggregation of α-synuclein and generation of Lewy bodies.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
NBI-assisted plasma heating with one or two injectors of fast neutral atoms was studied at the Globus-M2 spherical tokamak at the toroidal magnetic fields of 0.8–0.9 T and plasma currents of 0.35–0.4 ...MA. Measurements of the spatial temperature and electron density distributions, performed using the Thomson scattering diagnostics, showed a twofold increase in heating of plasma electrons during the injection of neutral particles with energies of up to 45 keV at the beam power of 0.75 MW, as compared to the ohmic heating regime. Switching on the second additional beam with the particle energy of up to 30 keV and power of up to 0.5 MW resulted in obtaining the hot ion mode in the range of mean plasma densities of (1.6–10) × 10
19
m
−3
. According to the data of active spectroscopy and neutral particle analyzer diagnostics, in the hot zone, the ion temperature reached 4 keV at the plasma density of 8 × 10
19
m
−3
, which is more than 2.5 times higher than the electron temperature.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The results of measuring the electron temperature and density spatial distributions in plasma of the Globus-M2 tokamak using the Thomson scattering diagnostics are presented. The diagnostics provides ...measurements throughout the entire tokamak discharge, starting from time of gas breakdown. The Thomson scattering data were analyzed in order to determine the positions of the last closed flux surface, the plasma magnetic axis, and the radius of inversion during the saw-tooth oscillations. The results of measurements performed during the internal reconnection of magnetic field lines are presents, as well as the dynamics of spatial distributions of electron temperature, density and pressure during the plasma transition to the H-mode. The results of measuring the electron temperature distribution in the scrape-off layer using the Thomson scattering diagnostics are also presented for distances up to 4 cm outside the last closed flux surface.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
Abstract
Doppler backscattering (DBS) was successfully previously used on the Globus-M tokamak. The diagnostic was utilised in the form of either a single-frequency or a four-frequency dual homodyne ...system. It was used primarily for the study of zonal flows, filaments and Alfvén eigenmodes. These phenomena are worth being studied both on the periphery and in the core region of the plasma in a tokamak. For this specific reason two multifrequency DBS systems were installed on the upgraded Globus-M2 tokamak. The first four-frequency system with dual homodyne detection had already been used on the Globus-M tokamak and has lower probing frequencies which provide measurements from the periphery plasma. The second and new six-frequency DBS system was installed with a non-linear transmission line that was adapted to generate probing signals at frequencies 50, 55, 60, 65, 70 and 75 GHz. In general, the range of probing frequencies corresponds to the region of critical plasma densities from 5 × 10
18
to 7 × 10
19
m
−3
at normal incidence. The pyramidal horn antennas are located inside the vacuum vessel with a special cardan-like rotator outside the camera so as to tilt antennas in the toroidal and poloidal directions. A previously developed code was applied to simulate 3D raytracing for all frequency channels. Calculations were carried out for different angles of incidence and for different electron density distributions in order to investigate the possibilities of the implementation of radial and poloidal correlation Doppler reflectometry. Examples of the DBS system application for study of plasma properties in the Globus-M2 tokamak are presented.
Abstract The paper presents the first experimental observation of an atypical phenomena during self-organization of dust particles into a one-dimensional chain structure levitated vertically in the ...plasma of a DC glow discharge. Using a laser, the third (middle) dust particle was removed from the chain of five particles so that the positions of the remaining particles did not significantly change, and a vacancy occurred in the place of the removed particle. This state of the chain turned out to be very stable, which is confirmed by the observation of the subsequent exchange of places of the fourth and the fifth particles of the chain upon the action of the laser on the forth particle. After the exchange process, vertical positions of all particles (first, second, fourth and fifth) in the chain remained almost the same as before the exchange, and the vacancy at the position of the third particle was preserved. The experimental data and the video record of the observed phenomena as well as the estimates of the plasma parameters are presented. An assumption has been made about the mechanism of the discovered phenomena that at present discharge conditions both the vacancy formation and the dust particles positions exchange are possible due to a strong ion wakes which are formed behind the upstream dust particles of the chain.
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IZUM, KILJ, NUK, PILJ, PNG, SAZU, UL, UM, UPUK
In this work we report on new examples of phenanthrolindiamides containing asymmetric centers in amide substituents. The synthesized ligands are expected to have complex thermodynamic behavior. Their ...structure was unambiguously confirmed by a combination of spectral analysis methods and X-ray analysis. It is shown that the obtained ligands form complexes with nitrates of rare-earth elements, and the stability constants of such complexes in acetonitrile solution were also measured. The performed solvent extraction tests revealed a significant effect of methyl groups in cyclic amide substituents on the distribution ratios and selectivity factors in the lanthanides(
iii
) and Am(
iii
) series in comparison with the previously studied ligands based on unsubstituted pyrrolidine. The observed effects are explained from the standpoint of quantum chemistry calculations taking into account possible stereoisomerism.
In this work we report on new examples of phenanthrolindiamides containing asymmetric centers in amide substituents.
In this paper, we discuss new data obtained by petrographical, geochemical, geochronological, and isotopic–geochemical study of magmatic rocks within the Malmyzh and Gion gold–copper-porphyry ore ...fields. Geochronological data show a Late Cretaceous age of their magmatic crystallization: Cenomanian (97–99 Ma) and Campanian (76–82 Ma) ages, respectively. Based on a comparative analysis of the studied samples igneous rocks with each other and with magmatic rocks of worldwide porphyry deposits, the results of a study using a secondary ion mass spectrometer of the patterns of distribution of trace elements (REE + Y, Hf, Ti, U, Th, and Pb) in accessory zircons from igneous rocks of the Malmyzh and Gion ore fields are discussed in order to estimate their potential ore content in the gold–copper-porphyry mineralization. Despite the fact that economic gold–copper ore mineralization within the potential Gion ore field was previously unknown, an analysis of the results shows, that according to the obtained values of indicative geochemical parameters of accessory zircons, the granitoids involved in its geological structure practically do not differ from the granitoids of both the neighboring Malmyzh deposit and most of the worldwide porphyry gold–copper deposits.
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EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, KILJ, KISLJ, MFDPS, NLZOH, NUK, OILJ, PNG, SAZU, SBCE, SBJE, SBMB, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
The origin and nature of extreme energy cosmic rays (EECRs), which have energies above the
5
⋅
10
19
eV
—the Greisen-Zatsepin-Kuzmin (GZK) energy limit, is one of the most interesting and complicated ...problems in modern cosmic-ray physics. Existing ground-based detectors have helped to obtain remarkable results in studying cosmic rays before and after the GZK limit, but have also produced some contradictions in our understanding of cosmic ray mass composition. Moreover, each of these detectors covers only a part of the celestial sphere, which poses problems for studying the arrival directions of EECRs and identifying their sources. As a new generation of EECR space detectors, TUS (Tracking Ultraviolet Set-up), KLYPVE and JEM-EUSO, are intended to study the most energetic cosmic-ray particles, providing larger, uniform exposures of the entire celestial sphere. The TUS detector, launched on board the Lomonosov satellite on April 28, 2016 from Vostochny Cosmodrome in Russia, is the first of these. It employs a single-mirror optical system and a photomultiplier tube matrix as a photo-detector and will test the fluorescent method of measuring EECRs from space. Utilizing the Earth’s atmosphere as a huge calorimeter, it is expected to detect EECRs with energies above
10
20
eV
.
It will also be able to register slower atmospheric transient events: atmospheric fluorescence in electrical discharges of various types including precipitating electrons escaping the magnetosphere and from the radiation of meteors passing through the atmosphere. We describe the design of the TUS detector and present results of different ground-based tests and simulations.
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DOBA, EMUNI, FIS, FZAB, GEOZS, GIS, IJS, IMTLJ, IZUM, KILJ, KISLJ, MFDPS, NLZOH, NUK, OBVAL, OILJ, PILJ, PNG, SAZU, SBCE, SBJE, SBMB, SBNM, UILJ, UKNU, UL, UM, UPUK, VKSCE, ZAGLJ
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