We present the results of calculations of the transition probabilities and energies of levels of the configurations 2s22p53s, 3p, 3d, 4s, 4p, 4d and others in the spectra of some Ne-like multicharged ionsNe-like multicharged ions. As a calculation method we have used the gauge-invariant relativistic many-body perturbation theoryRelativistic many-body perturbation theory (PT) with the optimized Dirac–Kohn–Sham zeroth approximation. The effective approach to construction of the optimal PT zeroth approximation is based on an accurate treatment of the PT lowest order multielectron exchange–correlation effects, in particular, the gauge dependent radiative contributions into the radiation width of atomic level for the certain class of the photon propagators. This value is considered to be the typical representative of the important multielectron exchange–correlation effects, whose minimization is a reasonable criterion in the searching for the optimal PT one-electron functions basis. All principal exchange–correlation corrections of the PT second order and dominated classes of the higher orders diagrams (polarization interaction, quasiparticles screening, etc.) have been taken into account. The obtained spectral data are compared with available experimental and alternative theoretical results.

We provide a detailed commentary on the energy calibration of the TA experiment described in our paper (arXiv:2404.16948 [astro-ph.HE]). That paper concludes that the TA energy estimation, which is tied to optical measurements, might be incorrect. A response from members of the TA Collaboration (arXiv:2407.12892 [astro-ph.HE]) states that this conclusion is wrong and "stems from a misinterpretation and an incorrect application of the TA energy deposit formula". Here we demonstrate that our formula for energy deposit is not in fact a rescaled modification of the TA equation, but follows from description of the processes occurring during the passage of charged particles through 1.2 cm thick scintillator. Our estimation of the TA detector response implies the correctness of the cosmic ray spectrum derived from readings of surface detectors of the array.

An analysis of calibrations of extensive air showers with zenith angles θ≤ 50^∘ and energies E_SD≤ 10^18.5 eV was carried out in experiments at the Yakutsk array and Telescope Array. The values of E_SD were determined from particle densities measured with ground-based scintillation detectors at a distance r = 800 m from shower axis. Measured densities were compared with the values obtained in simulations preformed with the use of CORSIKA code within the framework of QGSJet-II.04 hadron interaction model for primary protons. For showers with θ = 0^∘ the E_SD estimates of both arrays are very close, and their energy spectra are similar in shape and absolute value. Another Telescope Array calibration, based on measuring the EAS fluorescent radiation with optical detectors, gives underestimated energy E_FD = 0.787 × E_SD.

In this article a new method is proposed for estimating the mass composition of cosmic rays in individual events with energies above 1.25 ×10^19 eV. It is based on a joint analysis of experimental data and simulation results obtained using the QGSjet-II.04 model for muons with threshold energy E_μ = 1.0 ×cosθ GeV in air showers with zenith angles up to 60°. The data from ground-based and underground scintillation detectors of the Yakutsk EAS array were used. Separate groups of nuclei and other primary particles were found.

Here we consider the results of direct measurements of muons in extensive air showers with zenith angles $\theta \le 45^{\circ}$ and energy above $10^{17}$ eV, obtained at the Pierre Auger Observatory and Yakutsk array. In both experiments muons were registered with underground scintillation detectors with $\approx 1.0 \times \sec\theta$ GeV energy threshold. Measured density values were compared to theoretical predictions calculated within the framework of the QGSJet-II.04 hadron interaction model. They differ by factor $1.53 \pm 0.13$(stat). We demonstrate that this difference is due to overestimation of muon densities by 1.22 times and underestimation of primary energy by 1.25 times in the Auger experiment.

The effective relativistic approach to study of the energy, spectroscopic, radiation decay (excitation, ionization) characteristics of the Rydberg atomic systemsRydberg atomic systems in a Black-body radiation fieldBlack-body radiation field is presented and applied to computing the spectral parameters (effective lifetimes, transition probabilities) for a whole group of different nS, nP, nD states (n = 25–50) in the rubidium atom spectra, including highly excited states, at the temperature of 300 K. The approach is based on an advanced relativistic energy approachRelativistic energy approach (in a single-electron approximation realization) and the relativistic many-body perturbation theory with the Dirac–Kohn–Sham zeroth approximation. The key features of the approach are connected with the correct accounting for the exchange–correlation effects (the core polarization and screening effects, continuum pressure, non-Coulomb grouping of levels in Rydberg spectra, etc.), using optimized basis of relativistic wave functions and, respectively, fulfilling the principle of gauge invariance in calculation of the radiative decay matrix elements. The obtained spectroscopic data are compared with available experimental and alternative theoretical results.

The alkylation of substituted 5,6-dihydro[1,2,4]triazolo[3,4-a]isoquinolines with benzylic chlorides afforded quaternary 5,6-dihydro[1,2,4]triazolo[3,4-a]isoquinolinium salts. The reaction of the latter with PdCl2 and pyridine derivatives gave PEPPSI complexes. The cytotoxic activity of the new complexes was evaluated against the HEK293, A549, and HCT116 cell lines.

This chapter reviews the fundamentals of effective approach to computing different molecular characteristics (the potential energy curves, molecular constants, dipole moments, probabilities of radiative transitions etc.) of diatomic moleculesDiatomic molecules. The approach is based on new version of a formally exact Rayleigh-Schrödinger many-body perturbation theoryMany-body perturbation theory (PT) with ab initio gauge-invariant model potential zeroth approximation and with effective accounting for the complex many-body exchange–correlation effectsExchange-correlation effects as effects of the PT second and higher orders (including polarization interaction of external quasiparticles through a polarized core, or their mutual screening, iterations of the mass operator, pressure continuum, etc.). In contrast to the known similar PT versions, the fundamental ab initio procedure for construction of a model potential (MP) zeroth approximation is developed. The problem of the construction of the optimal one-electron representation in the theory of the multielectron systems is reduced to the minimization of the gauge dependent multielectron contribution to the radiation widths of electron states (transition probabilities). The perturbation theory first order correction is calculated exactly, the high order contributions are accounted for effectively. Two main types of high order corrections are investigated: "polarization" interaction of two "above core" particles and effect of the mutual screening of these particles. Some illustrative results of calculation of the energy and spectral parametersElectron structure and spectral parameters of some diatomic moleculesDiatomic molecules (the sodium, rubidium and caesium dimers) are presented. The computational results for molecular constants of the investigated molecules are in physically reasonable agreement with both the available experimental data and the results of other calculations using alternative, in particular empirical approaches.

Рассмотрены результаты прямых измерений плотности мюонов в широких атмосферных ливнях (ШАЛ) с зенитными углами \(\theta\leqslant 45^{\circ}\) и энергиями \(E_{0}\geqslant 10^{17}\) эВ, полученных в эксперименте Оже и на Якутской установке. Мюоны в обоих случаях регистрировались подземными сцинтилляционными детекторами с одинаковой пороговой энергией \(E_{\mu}\approx 1.0\sec\theta\) ГэВ. Измеренные величины сравниваются с теоретическими значениями, вычисленными по модели развития ШАЛ QGSJET-II-04 из пакета программ CORSIKA. Они различаются между собой в \(1.53\pm 0.13\) (stat). Показано, что это различие обусловлено завышенной в 1.22 раза плотностью мюонов и заниженной в 1.25 раза первичной энергией в эксперименте Оже.

Lateral distribution functions of particles in extensive air showers with the energy E_0≈10^19 1pt eV recorded by ground-based and underground scintillation detectors with a threshold of E_μ ≈ 1pt 1.0 ×sec 1ptθ GeV at the Yakutsk array during the continuous observations from 1986 to 2016 have been analyzed using events with zenith angles θ ≤ 60°. Experimental functions have been compared to the predictions obtained with the QGSJet-01-d hadron interaction model by applying the CORSIKA code. The entire dataset indicates that cosmic rays consist predominantly of protons.

Particle lateral distributions were investigated in cosmic ray air showers with energy E_0≃ 10^18 eV registered at the Yakutsk array with surface and underground scintillation detectors with E_μ≃ 1×θ GeV threshold during the period of continuous observations from 1986 to 2016. The analysis covers events with arrival direction zenith angles θ≤ 60^∘ within five intervals with step Δcosθ=0.1 . Experimental values were compared to simulation results obtained with the use of CORSIKA code within the framework of QGSJet-01-d hadron interaction model. The whole dataset points at probable cosmic ray composition which is close to proton one.

The lateral distribution of particles in extensive air showers from cosmic rays with energy above 10 17 eV registered at the Yakutsk complex array was analyzed. Experimentally measured particle densities were compared to the predictions obtained within frameworks of three ultra-high energy hadron interaction models. The cosmic ray mass composition estimated from the readings of surface-based and underground detectors of the array is consistent with estimations obtained from measurements of lateral distribution of the air showers Cherenkov light emission. A comparison was made with the results of direct measurement of the muon component performed at the Pierre Auger Observatory. It is demonstrated that the densities of muon flux measured at Yakutsk array are consistent with results of fluorescent light measurements and disagree with results on muons obtained at the Auger array.

Lateral distribution of muons in extensive air showers registered at the Yakutsk array was investigated. The analysis covers two periods of observation: before 2018 and after 2020, when the revision of muon detectors with 1-GeV threshold was complete. Measured values of muon density are compared to computational results obtained within the framework of two hadron interaction models. Within the energy domain above 1018 eV the best agreement is observed for proton composition primary cosmic rays.

Исследованы функции пространственного распределения частиц в широких атмосферных ливнях (ШАЛ) на Якутской установке наземными и подземными сцинтилляционными детекторами с порогом Eµ ≈ 1.0 × sec θ ГэВ от космических лучей с энергией E0 ≈ 1019 эВ за период непрерывных наблюдений 1986-2016 гг. Использованы данные c зенитными углами θ ≤ 60 . Экспериментальные величины сравниваются с расчетными, выполненными по модели развития ШАЛ QGSJET-01-d из пакета программ CORSIKA. Вся совокупность рассмотренных данных указывает на вероятный состав космических лучей, близкий к протонному.

Lateral distribution functions of particles in extensive air showers with the energy $${{E}_{0}} \approx {{10}^{{19}}}{\kern 1pt} $$ eV recorded by ground-based and underground scintillation detectors with a threshold of $${{E}_{\mu }}$$ $$ \approx {\kern 1pt} 1.0 \times {\text{sec}}{\kern 1pt} \theta $$ GeV at the Yakutsk array during the continuous observations from 1986 to 2016 have been analyzed using events with zenith angles θ ≤ 60°. Experimental functions have been compared to the predictions obtained with the QGSJet-01-d hadron interaction model by applying the CORSIKA code. The entire dataset indicates that cosmic rays consist predominantly of protons.

Particle lateral distributions were investigated in cosmic ray air showers with energy E-0 similar or equal to 10(18) eV registered at the Yakutsk array with surface and underground scintillation detectors with E-mu similar or equal to 1 x sec theta. GeV threshold during the period of continuous observations from 1986 to 2016. The analysis covers events with arrival direction zenith angles theta <= 60 degrees within five intervals with step Delta cos theta = 0.1. Experimental values were compared to simulation results obtained with the use of CORSIKA code within the framework of QGSJet-01-d hadron interaction model. The whole dataset points at probable cosmic ray composition which is close to proton one.

This chapter aims at highlighting how green chemistry principles are being incorporated into radiochemistry, by presenting a selective review of latest novel trends and conceptions in modern theoretical radiochemistry and their interfaces with green chemistry. The chapter reviews some of the most promising approaches for the processing and transmutation of radioactive elements at industrial level, after processing spent nuclear fuel. The use of gamma neutron transmutation methods, as well as methods involving selective laser separation of heavy radioactive elements (isotopes) to enable greener handling of radioactive materials, is one of the foundations of green radiochemistry. For example, one of the last processes in radiochemical technologies entails the regeneration of spent uranium. The problem can be radically solved by the gamma-neutron transmutation method, which complements the traditional fission process by other electron-, photon-, and neutron-physical methods, to realize a sort of circular route by which the most dangerous products of the fission process become sources of neutrons for reproducing the power generating potential of uranium, and only stable isotopes and low-activity radionuclides reach the environment. Furthermore, the use of laser isotope separation (for example, separation of the 90Sr, 137Cs, and 129I isotopes from the corresponding stable fragments Sr, Cs, and I) raises the efficiency of transmutation processes and reduces the energy spent on them. All these outcomes are in full agreement with the principles of green chemistry. The need to calculate the optimal conditions for the implementation of the described processes stimulates the determination of both energy and radiative and spectroscopic characteristics of different isotopes in a nuclear fuel, and in a variety of physical conditions, including in the presence of external electromagnetic fields. The computational methods of quantum chemical modelling are further applied for a better understanding of the processes involved. New quantum models integrating computational chemical and dynamical approaches are here presented in detail, considering the most optimal conditions for the realization of transmutation cycles, including laser photochemical separation of radioactive isotopes.

We present a new generalized mathematical approach to analysis and modelling the characteristics of the chaotic atmospheric dynamical system, including natural air ventilation in the atmosphere of the industrial city. The approach is based on the Arakawa-Schubert model of calculation of cloud convection, modified to calculate the current involvement of the ensemble of clouds, and hydrodynamical prediction model (with correct quantitative accounting for the turbulence in an atmosphere of the urban zone) and theory of a complex geophysical field. The method for computing a turbulence spectra inside the city’s (urban) zone is based on the generalized model of the tensor equations for turbulent tensions. The velocity components of an air flux over the city area are determined in an approximation of “shallow water” and found on the basis of the advanced spectral series expansion approach. The results of the PC simulation experiments for an chaotic air ventilation and a chaotic heat transfer in atmosphere of industrial city, including the data of modelling ventilation (mesocirculation) parameters over territory of Odessa are presented. The numerical data on a current function and velocity potential are computed and analyzed presented for a few hydrodynamic (synoptic) situations in the Odessa city.

Triterpene Schiff bases 2 – 5 were prepared for the first time by reacting N -heterocyclic carbaldehydes with β -allobetulamine. Their structures were confirmed using 1 H NMR and 13 C NMR spectra and 2D experiments. The structure of 5 was also proved by an X-ray crystal structure analysis.