Abstract
This paper presents the gamma-ray detection performance of the newly developed MAPD-3NM-II type SiPM sensor array (4
$$\times$$
×
4) with
$$\hbox {LaBr}_3$$
LaBr
3
(Ce) scintillator. The ...gamma-ray spectra of various sources have been measured in the energy range from 26 keV up to 1332 keV. The newly developed array based on MAPD-3NM-II sensors proved
$$\sim$$
∼
22% enhancement in energy resolution in comparison to the former MAPD-3NM-I based array. The energy resolution of 662 keV gamma-rays measured by MAPD-3NM-II was 3.3% while clearly surpassing 4.25% resolution of MAPD-3NM-I predecessor. The enhancement is related to the high PDE of the new MAPD-3NM-II. Obtained results show that the new MAPD-3NM-II demonstrated good energy resolution and linearity in the studied energy region. The energy resolution of the new detector developed based on MAPD-3NM-II was better than all previous products of MAPD.
The paper contains the proof of the existence of two different positive solutions of the problem
involving convex and concave nonlinearities, the parameter
, and the variables
. The coefficient ...matrix
satisfies the nonuniform ellipticity condition
in a bounded domain
,
,
. To achieve the goal, the authors consider the conditions on the range of nonlinearity exponents
and
(or
and the additional condition
) and
for a sufficiently small
; positive weight functions
,
belong to the corresponding Muckenhoupt classes in the metric of
-dimensional Euclidean space and also the balance condition of Chanillo–Wheeden type holds.
The aim of the work is to develop a mechanism for cross-border carbon regulation for countries importing products to the EU, which will equally allow importing countries to fulfill the conditions of ...the Carbon Border Adjustment Mechanism (CBAM), encourage manufacturers to reduce CO2 emissions, and also provide importing countries with opportunities to replenish their budget by introducing paid emission quotas greenhouse gases. The work makes a significant contribution to stimulating the reduction of CO2 emissions by producers due to the proposed tax mechanism and preventing the leakage of greenhouse gases on the territory of third countries according to the CBAM policy. The EU evaluates double taxation, so if a carbon tax has been withdrawn in the territory of the exporting country, then such a tax will not be levied again in the EU. All this involves stimulating exporting countries by creating their own taxation systems, which will have international qualifications and be recognized by countries around the world. When choosing a taxation mechanism, it is important to choose the specifics for visiting group gases. The study was conducted on the basis of methods of comparison, modeling, analysis and deduction.
In this work cubic phase, silicon carbide nano-powders were irradiated at the high-flux pulsed reactor IBR–2 (Dubna, Russia). The 3C–SiC powder was irradiated with neutron doses up to 1015 n/cm2. The ...irradiated samples were then analyzed using X-ray diffraction, Raman spectroscopy, Positron annihilation spectroscopy, and Fourier Transform Infrared Spectroscopy. The XRD analysis showed a slight decrease in the lattice parameters with the increase in neutron fluences. The results obtained from positron annihilation measurements were compared to the theoretical calculations, to recognizing the type of structural defect in the samples. A positron lifetime component 355 ps associated with the calculated values for clusters containing of 13–21 vacancies was identified. The concentration of these defects was estimated to be in the region of 5 ppm, and was very similar to the one identified on the unirradiated sample. The results also indicate high irradiation resistivity of the 3C–SiC after irradiation.
•Nano silicon carbide was irradiated fast neutron flux up to 1015 n/cm² and energy of neutron flux E≥1 MeV at room temperature.•A positron lifetime component 355 ps associated with the calculated values for clusters containing of 13 to 21 vacancies was identified.•At small fluences up to 1.3×1013 n/cm² the lattice parameters decrease from 4.3571 Å to 4.3527 Å is observed.
In this paper we present the results of studies into the frequency and temperature dependences of the dielectric loss tangent and the real and imaginary parts of the permittivity in MnGaInSe
4
single ...crystals in an alternating electric field. The main type of dielectric losses in MnGaInSe
4
single crystals in the frequency range of 8 × 10
3
–3 × 10
5
Hz is established to be electrical conductivity losses, while the conductivity is characterized by the zone-hopping mechanism. The activation energies of current carriers of single crystals are determined. The real and imaginary parts of the permittivity are found to undergo significant dispersion, which is of a relaxation nature.
The frequency and temperature dependences of the ac electrical conductivity of the MnGaInSe
4
single crystals have been investigated. It has been established that, in the temperature range of ...295.5–360 K at frequencies of 2 × 10
4
–10
6
Hz, the electrical conductivity obeys the regularity σ ~
f
S
(0.1 ≤
S
≤ 1.0). It is shown that the frequency dependence of the electrical conductivity for the MnGaInSe
4
single crystal can be explained using a multiplet model and the conductivity in these single crystals is implemented via the band-hopping mechanism. The activation energies have been determined on the basis of dependences logσ ~ 10
3
/
T
.
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