Factors affecting the stability of gadolinium- and neodymium-loaded liquid organic scintillators intended for use in large-scale experimental facilities for neutrino physics and astrophysics are ...examined. The effect of composition (type and structural formula of gadolinium and neodymium compounds) on the optical properties of such scintillators is analyzed. It is shown that the oxidation of alkylbenzenes is one of the reasons for the degradation (decrease in transparency) of the scintillators. Gadolinium and neodymium compounds may be catalysts for the oxidation processes.
We consider the problem of minimizing the risk taken on by investors in a two-tier (banking) system of lending and a system of peer-to-peer lending, assuming the incoming risks to be constant. It is ...shown that with the introduction of a special (nonsystematic) risk, the peer-to-peer lending model turns out to be optimal.
We consider the process of tokenization of credits in the peer-to-peer lending model. The investor risk is formulated in terms of reliability theory. This allows us to write restrictions on the ...parameters of the token package that provide a given risk and profitability for the known parameters of the loan portfolio.
Synthine and T-6 propellant are studied as new basic solvents for creating liquid organic scintillators. The light attenuation length in these solvents (both those obtained from the manufacturer and ...those subjected to chromatographic purification on Al
O
) was measured along with the relative light yield of scintillators based on them. The chemical composition of synthine was determined by the method of chromato-mass spectrometry and UV spectrophotometry. A Nd-loaded scintillator (
9 g/L) based on a synthine–pseudocumene mixture was created, and its light yield (LY 60
) was measured with respect to a scintillator based on linear alkyl benzene (LAB).
It becomes difficult and expensive to control TeV-particle trajectories using electromagnets to obtain extracted beams at accelerators. For these purposes, high-gradient devices based on bent ...crystals are more suitable. These crystals can serve as superstrong lenses with a focal length of less than 1 m with an equivalent magnetic field of 1000 T. In this work, a scheme based on two successive focusing crystals has been implemented to form a 50 GeV axially symmetric beam with a small divergence of 30 μrad in both the horizontal and vertical planes. One of the promising applications of this scheme is the creation of high-energy neutrino beams.
A modification of the LENS (Low Energy Neutrino Spectroscopy) project for spectroscopy of solar neutrinos with energies above about 715 keV on the basis of new technologies and solutions is examined. ...The respective detector employs
In nuclei as a target for neutrinos. The creation of a detector containing about 200 t of a scintillator loaded with 10 t of indium will make it possible to measure, within five years, the energy spectra of solar neutrinos from
Be, neutrinos from the CNO cycle, and
neutrinos with small systematic errors. The detector was simulated in the form of a set of cells of a liquid scintillator doped with indium (about 10
in weight). Necessary technical conditions for detector cells are formulated, and the possible counting rate for events induced by internal and external backgrounds and characterized by an energy release of 600 to 1600 keV is estimated. It is shown that such a detector is implementable, in principle.
The generation of beams of secondary particles (π and
K
mesons) at proton accelerators is a difficult scientific and engineering problem. To obtain narrow directional particle beams for experiments, ...intense extracted proton beams are used, secondary particles (π and
K
mesons) are generated at an external target, and they are focused and transferred through long magneto-optical channels. In this work, a surprisingly simple method based on a crystal focusing device has been proposed to obtain secondary beams. An experiment on the production of a secondary beam using a crystal has been performed at the U-70 accelerator. Schemes for the formation of beams with energies
E
~ 1 TeV have been proposed for large colliders such as the Large Hadron Collider.
The Multi-Purpose Detector (MPD) is constructing to study the properties of the hot and dense matter created in heavy-ion collisions in the energy range of 4-11 A*GeV where the maximum baryonic ...density is expected. The crucial detector in the new experimental setup is a large-sized barrel electromagnetic calorimeter (ECal), designed for precise spatial and energy measurements for photons and electrons. Taking into account the requirements of high energy resolution, dense active medium with the small Moliere radius, and high segmentation of ECal, the Shashlyk-type electromagnetic calorimeter with projective geometry has been selected. The mass production of ECal modules has been started. In this talk, we report about methods and technologies for the quality control of ECal modules and their components.
The paper deals with the phylogenetic and functional microbial diversity in the samples of umbric luvisol contaminated and uncontaminated with hydrocarbons and of urban stratozem. High-throughput ...sequencing of the V3–V4 region of the 16S rRNA gene revealed predomination of bacteria of the phyla
Proteobacteria
,
Actinobacteria
, and
Acidobacteria
in the studied soil samples. Bacteria of the genera
Sphingomonas
,
Bradyrhizobium
, and
Pseudolabrys
in the samples of umbric luvisol and bacteria of the genera
Brevundimonas
,
Stenotrophomonas
, and
Streptomyces
in urbostratozem had the greatest potential functional activity in conversion of nitrogen compounds, degradation of chloroalkanes, chloroalkenes, and benzoate. Strains of
Stenotrophomonas maltophilia
, which degraded oil, petroleum products, and polycyclic aromatic hydrocarbons (PAHs, phenanthrene, anthracene, and pyrene) were isolated from oil-contaminated soils. Under microcosm conditions, microorganisms of umbric luvisol efficiently degraded various components of naphthenic-methane and methane-naphthenic oil. While the content of aromatic components in naphthenic-methane oil degraded by the soil microbial community and by the community enriched with
S. maltophilia
strain P420c was almost the same, in the variant with bioaugmentation the degradation process of these components proceeded 14 days faster. The enrichment of soil with specific degraders of PAHs and aromatic compounds may be appropriate for the soils of northern regions with a low duration of the summer period, which are polluted with oil with a high content of aromatic and asphalt-resinous compounds.
In the TeV energy domain, it becomes difficult and very costly to control the trajectories of particles using electromagnets to obtain the extracted beams on accelerators. Highly gradient devices ...based on curved crystals are more suitable for these purposes. These crystals can work as super-strong lenses with a focal length of less than 1 m and with an equivalent magnetic field of 1000 T. In this paper, a scheme for the formation of a divergent beam with an energy of 50 GeV by two sequentially arranged focusing crystals is implemented to create an axially symmetric beam with a small divergence of 30 µrad in both horizontal and vertical planes. One promising application of such a scheme is the creation of high-energy neutrino beams.
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