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This paper presents a study of the current state of standardisation opportunities in the field of Artificial Intelligence looking forward to 2030. As an example of the artificial intelligence technologies use for development purposes, the team of authors considered general education activities. The study analysed and established the potential risks of using AI technologies in educational activities and cited factors which, according to the authors, could constrain the development of the AI field. The characteristics of GOST 59895-2021, GOST 59900-2021 and GOST R 59899-2021, which came into force in 20022, are given. As a conclusion to the paper, practical recommendations on the application of new GOSTs in the field are given. The mentioned GOSTs in perspective should allow removing restrictions on the use of AI technologies in education, overcoming the difficulties of assessing the applied effect of the use of artificial intelligence systems.

This work is devoted to the study of sanitary and hygienic monitoring of fishery water use objects in Murmansk region. The paper presents assessment of the ecological and sanitary conditions of fishery reservoirs in the Arctic region of the Kola and Tuloma rivers for the period 2016-2018 based on the use of microbiological, hydrochemical and parasitological indicators, as well as the integral index of surface water pollution. Hydrochemical studies consisted of determining the biochemical oxygen consumption, the mass content of NH4+, NO2-, NO3-, iron, and dissolved O2. The assessment of the river waters sanitary state was carried out by means of microbiological and parasitological methods. The microbiological parameters were used to determine the number of common and thermotolerant coliform bacteria, coliphages, and the presence of intestinal infections pathogens. The water of rivers does not meet the hygienic standards in terms of hydrochemical indicators in seventeen percent and in terms of microbiological indicators in five percent of cases. According to parasitological indicators, hygienic standards meet the requirements. In five points of water sampling, the water of the Tuloma and Kola rivers was evaluated as pure according to the integral hydrochemical index value and belongs to the second category of quality. In general, the high-water quality of Murmansk region rivers was noted. In conclusion, it should be emphasized that systematic monitoring of water supply sources is necessary to obtain an idea of the indicators’ variability and to assess the rivers pollution degree.

This work is devoted to the study of sanitary and hygienic monitoring of fishery water use objects in Murmansk region. The paper presents assessment of the ecological and sanitary conditions of fishery reservoirs in the Arctic region of the Kola and Tuloma rivers for the period 2016-2018 based on the use of microbiological, hydrochemical and parasitological indicators, as well as the integral index of surface water pollution. Hydrochemical studies consisted of determining the biochemical oxygen consumption, the mass content of NH4+, NO2-, NO3-, iron, and dissolved O2. The assessment of the river waters sanitary state was carried out by means of microbiological and parasitological methods. The microbiological parameters were used to determine the number of common and thermotolerant coliform bacteria, coliphages, and the presence of intestinal infections pathogens. The water of rivers does not meet the hygienic standards in terms of hydrochemical indicators in seventeen percent and in terms of microbiological indicators in five percent of cases. According to parasitological indicators, hygienic standards meet the requirements. In five points of water sampling, the water of the Tuloma and Kola rivers was evaluated as pure according to the integral hydrochemical index value and belongs to the second category of quality. In general, the high-water quality of Murmansk region rivers was noted. In conclusion, it should be emphasized that systematic monitoring of water supply sources is necessary to obtain an idea of the indicators’ variability and to assess the rivers pollution degree.

Samples of the composition Ce0.9(Mg1 – xNix)0.1O2 (0 ≤ x ≤ 1, step x = 0.1) have been obtained by gel combustion followed by hydrothermal treatment. X-ray powder diffraction data have showed that after gel combustion and annealing at 1100°C, composite CeO2 (fluorite structure)/solid solution Mg1 – xNixO (halite structure) is formed, and additional hydrothermal treatment followed by annealing promotes the formation of limited solid solution Ce0.9(Mg1 – xNix)0.1O2. According to the results of IR spectroscopy, the CeO2/Mg1 – xNixO composite does not adsorb CO2 even in the presence of water vapor, which is also confirmed by diffuse reflectance spectra in the UV-visible region. On the contrary, the Ce0.9(Mg1 – xNix)0.1O2 solid solution absorbs CO2, as evidenced by the results of IR spectroscopy and thermogravimetric analysis. [ABSTRACT FROM AUTHOR]

Electrical properties, deep traps spectra, microcathodoluminescence (MCL) spectra measurements, MCL imaging, and electron beam induced current (EBIC) imaging were performed for undoped GaN films grown by metalorganic chemical vapor deposition using maskless epitaxial lateral overgrowth on basal plane sapphire. The films showed a low dislocation density of ∼108 cm-2 in the laterally overgrown wings and an order of magnitude higher dislocation density in vertical growth seed regions, as determined by MCL and EBIC imaging. The polarity of EBIC signal measurements and the room temperature capacitance-voltage characteristics suggested that the high-dislocation-density seed regions were high-resistivity p-type, with the Fermi level pinned near Ev + 0.4 eV, as determined by admittance spectroscopy. The wing regions were n-type, with low residual donor concentration of some 1014 cm-3 near the surface. The donor concentration further decreased upon movement towards the sapphire substrate. Some possible explanations of the observed effects are discussed. [ABSTRACT FROM AUTHOR]

The electrical properties, presence of deep electron and hole traps and photoluminescence spectra were measured for undoped a-GaN films grown by metal-organic chemical vapor deposition (MOCVD) in a two-stage process using a high V/III ratio at the first stage and low V/III ratio at the second stage. Growth was performed on r-sapphire substrates with a high temperature GaN nucleation layer. The films showed a full width at half maximum of 450-470 arcseconds for the (11-20) x-ray rocking curve with little anisotropy with respect to the sample rotation around the growth direction. The stacking fault (SF) density determined by selective etching was ∼5 × 104 cm-1. The residual donor concentration was 1014-1015 cm-3, with a very low density (2.5 × 1013 cm-3) of electron traps located at Ec - 0.6 eV, which are believed to be one of the major non-radiative recombination centers in nonpolar GaN. Consequently, the films showed a high intensity of bandedge luminescence with negligible contribution from defect bands associated with SFs. In contrast to previously studied nonpolar GaN films, the a-GaN layers showed a high concentration of gallium-vacancy-related acceptors near Ev + 1 eV and a strong yellow luminescence band, both indicating that growth conditions were effectively N-rich. a-AlGaN/GaN heterojunctions with thin heavily Si doped AlGaN barriers made on a-GaN substrates showed two-dimensional electron gas (2DEG) concentrations of 1.2 × 1013 cm-3, with 2DEG mobility of 80 cm2/Vs. Capacitance-voltage profiling of Schottky diodes on these HJs suggest that the 2DEG is fully depleted by the built-in voltage of the Schottky diode. [ABSTRACT FROM AUTHOR]

Optical deep level spectroscopy (ODLTS) and microcathodoluminescence (MCL) spectra were measured for a large group of n-GaN samples grown via metalorganic chemical vapor deposition (MOCVD), epitaxial lateral overgrowth (ELOG), or hydride vapor phase epitaxy (HVPE). In the MOCVD and ELOG samples, the ionization energy of dominant hole traps H1 was dependent on the excitation conditions and was ∼0.9 eV for high injection levels providing saturation of the ODLTS peak magnitude. The trap concentration increased with increasing Si donor concentration and correlated with the yellow band intensity in the MCL spectra. For the HVPE samples, the hole trap spectra were radically different from the MOCVD case: four hole traps-H2, H3, H4, and H5-with activation energies of 0.55, 0.65, 0.85, and 1.2 eV, respectively, were detected. In the MCL spectra, a broad green band that peaked near 2.5 eV was observed in addition to the usual yellow luminescence near 2.3 eV. This green band was attributed to the transitions involving the H4 hole traps. Possible identities of the hole traps detected in the MOCVD/ELOG and HVPE samples are discussed. [ABSTRACT FROM AUTHOR]

We studied 10 MeV electron irradiation effects in a group of n-GaN films grown by standard metalorganic chemical vapor deposition (MOCVD) and by epitaxial lateral overgrowth (ELOG) techniques. The samples were either undoped or Si-doped, so that the shallow donor concentrations ranged from 1014 cm-3 to 3 × 1018 cm-3. It was found that electron irradiation led to the compensation of n-type conductivity and that the carrier removal rate substantially increased with an increase in the starting donor concentration. For the MOCVD samples, it was observed that the main compensating defect introduced by electrons was a 0.15 eV electron trap detected by admittance spectroscopy. Once the Fermi level crossed the level of these traps two other centers with activation energies of 0.2 and 1 eV were found to contribute to the compensation, so that after high doses, the Fermi level in moderately doped samples was pinned near Ec -1 eV. In ELOG samples the 0.15 eV electron traps were not detected. Instead only the 0.2 and 1 eV traps were introduced by irradiation. The carrier removal rate in the ELOG n-GaN was found to be measurably lower than for MOCVD samples with a similar doping level. The results are compared to previously published data and possible models of compensation are discussed. [ABSTRACT FROM AUTHOR]

Electrical and optical properties of AlGaN grown by molecular beam epitaxy were studied in the Al composition range 15%–45%. Undoped films were semi-insulating, with the Fermi level pinned near Ec-0.6–0.7 eV. Si doping to (5–7)×1017 cm-3 rendered the 15% Al films conducting n-type, but a large portion of the donors were relatively deep (activation energy 95 meV), with a 0.15 eV barrier for capture of electrons giving rise to strong persistent photoconductivity (PPC) effects. The optical threshold of this effect was ∼1 eV. Doping with Fe to a concentration of ∼1017 cm-3 led to decrease in concentration of uncompensated donors, suggesting compensation by Fe acceptors. Addition of Fe strongly suppressed the formation of PPC-active centers in favor of ordinary shallow donors. For higher Al compositions, Si doping of (5–7)×1017 cm-3 did not lead to n-type conductivity. Fe doping shifted the bandedge luminescence by 25–50 meV depending on Al composition. The dominant defect band in microcathodoluminescence spectra was the blue band near 3 eV, with the energy weakly dependent on composition. [ABSTRACT FROM AUTHOR]

Ni/GaN Schottky diode radiation detectors were fabricated on 3-μm-thick unintentionally doped n-GaN films grown by molecular beam epitaxy (MBE) and metal organic chemical vapor deposition (MOCVD) and on 12-μm-thick undoped n-GaN layers prepared by epitaxial lateral overgrowth (ELOG). The reverse current of all detector structures was <10-9 A for bias voltages necessary for detector operation, with the level of background donor doping of <1015 cm-3. With this doping level the space charge region of the Schottky diode could be extended to the entire thickness of the films. The charge collection efficiency of the detectors was close to 100% for MOCVD and ELOG detectors for α-particles with range comparable to the thickness of the layer. Electrical properties and deep trap spectra were also studied. The collection efficiency decreased when the concentra-tion of deep electron traps, particularly Ec-0.6 eV traps, increased in MBE grown films. [ABSTRACT FROM AUTHOR]

The electrical properties, admittance spectra, microcathodoluminescence, and deep trap spectra of p-AlGaN films with an Al mole fraction up to 45% grown by both metal organic chemical vapor deposition (MOCVD) and molecular beam epitaxy (MBE) were compared. The ionization energy of Mg increases from 0.15 to 0.17 eV in p-GaN to 0.3 eV in 45% Al p-AlGaN. In p-GaN films grown by MBE and MOCVD and in MOCVD grown p-AlGaN, we observed additional acceptors with a concentration an order lower than that of Mg acceptors, with a higher hole capture cross section and an ionization energy close to that of Mg. For some of the MBE grown p-AlGaN, we also detected the presence of additional acceptor centers, but in that case the centers were located near the p-AlGaN layer interface with the semi-insulating AlGaN buffer and showed activation energies considerably lower than those of Mg. [ABSTRACT FROM AUTHOR]

Electrical properties and deep trap spectra are reported for MgZnO(P) films grown by pulsed laser deposition on undoped n-ZnO substrates. The as-grown films are n type with a “bulk” donor concentration of ∼1018 cm-3 and have a compensated high resistivity layer near the surface. Deep trap spectra in these films are dominated by electron traps with an activation energy of 0.3 eV, hole traps with an activation energy of 0.14 eV, and some unidentified electron traps with a barrier for capture of electrons. After annealing in oxygen at 800 °C the MgZnO(P) becomes p type, with the dominant hole traps having an activation energy of 0.2 eV. The space charge region of the formed p-n junction is mainly located in the n-ZnO substrate. The main hole traps in this part of the heterojunction have activation energies of 0.14 and 0.84 eV, while the main electron traps have activation energies of 0.15 and 0.3 eV. [ABSTRACT FROM AUTHOR]

Electrical and optical properties of undoped n-ZnO crystals implanted with 50 keV protons with doses from 5×10[sup 13] to 5×10[sup 15] cm[sup -2] are reported. Proton implantation leads to a decrease of the carrier concentration in the near-surface region, but at the end of the proton range shallow donors are observed whose concentration tracks the implant dose and that we attribute to hydrogen donors. Three deep electron traps with apparent activation energies of 0.55, 0.75, and 0.9 eV are introduced by proton implantation. The 0.9 eV traps have been observed through the increased thermal stability of the Schottky diodes prepared on heavily implanted n-ZnO compared to unimplanted or lightly implanted samples. In addition, hole traps located 0.16 eV above the valence band edge were introduced by implantation. Proton implantation also led to the formation of persistent-photocapacitance-active defects and to considerable decrease in the intensity of the band edge luminescence and in the value of the photocurrent of the Au/n-ZnO Schottky diodes. When compared with other wide-band gap materials, such as GaN, the recombination properties of n-ZnO are shown to be more resistant to deterioration upon proton implantation. © 2003 American Institute of Physics. [ABSTRACT FROM AUTHOR]

Nonpolar (11-20) a-GaN/InGaN quantum well (QW) structures were grown by metalorganic chemical vapor deposition on r-plane (1-102) sapphire substrate using a two-stage growth procedure. Our studies demonstrate that, in contrast to polar QWs, these structures show the presence of deep electron traps with activation energy of 0.41 eV in admittance spectra and 1 eV electron traps in capacitance transient spectra. These traps are suspected to be nonradiative recombination centers, decreasing the nonpolar QW photoluminescence (PL) efficiency in our structures compared to polar structures. The PL efficiency of nonpolar QWs is shown to be greatly enhanced by coupling to localized surface plasmons formed by Ag nanoparticles. [ABSTRACT FROM AUTHOR]