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Long-wave Raman spectra of some normal alcohols (from n -pentanol to n -decanol) in the liquid phase were registered. The regularities in the dependencies of Raman bands frequencies on the number of carbon atoms in the hydrocarbon chain were deduced. The calculations of Raman spectra of the studied molecules, their equilibrium structures and possible conformers were carried out in the approximation B3LYP/cc-pVDZ. These results in combination with the analysis of literature data allowed to explain the observed regularities in Raman band positions in the spectral range of 200–600 сm −1 and their shifts upon increasing length of the chains. It was found that the plane configurations dominate in the liquid phase for molecules with short- and moderate-chain lengths. The elongation of the chain leads to the decrease of the fraction of plane conformers and in n -decanol the plane structure is completely absent.

Low-temperature infrared absorption spectra are obtained for ethanol isolated in an argon matrix at temperatures of 20–45 K range for ratios of the numbers of the molecules being studied to the numbers of matrix atoms of 1:1000 and 1:2000. A preliminary interpretation of the spectra is obtained on the basis of the temperature variations in the spectra and published data. The structure of the ethanol conformers, rotational constants, and internal rotation barriers of the methyl and hydroxyl groups are calculated in the B3LYP/cc-pVQZ approximation. The harmonic and anharmonic IR spectra of the gauche- and trans-conformers are calculated in the same approximation. The force fields of the two conformers and the distributions of the potential energy of the normal vibrations are calculated and compared for a general set of dependent coordinates. Anharmonicity effects are taken into account by introducing spectroscopic masses for the hydrogen atoms when calculating the normal vibrations in the harmonic approximation.

Infrared absorption spectra of methyl alcohol isolated in an argon matrix are recorded experimentally. The transformation of the structure of the spectral bands with rising matrix temperature is analyzed in the spectral region of the C–O and O–H stretch deformation vibrations (1000–1100 and 3000–3800 cm−1). The experimental data are interpreted using quantum-chemical modelling of an optimal spatial structure and of the vibrational spectra of different nano-sized methyl alcohol clusters. The structure of the clusters changes gradually as the temperature of the argon matrix is raised from 10 to 50 K.

This article presents a line of development of formal design methods that is based on the concepts of algebraic programming and algebraic dynamic program models using rewriting rules for the automated design of efficient programs for graphics processing units. The developed formal methods are illustrated by examples that show high efficiency of transformations.

The rare decay KL0 → π0ν\( \tilde v \) branching ratio measurement is one of the clearest Standard Model test. Calculations based on the SM predict Br(KL0 → π0ν\( \tilde v \)) ≈ 2.8 × 10−11, but the most accurate experimental value Br(KL0 → π0ν\( \tilde v \)) < 6.7 × 10−8 (90% C.L.). We present design of a new experimental setup KLOD (U-70 accelerator, IHEP, Protvino) for KL0 → π0ν\( \tilde v \) branching ratio measurement. Sensitivity of the KLOD experiment will be enough for registration of 2.4 events KL0 → π0ν\( \tilde v \) for every 10 days of the data taking (according to SM predictions).

This paper presents results on development of the auto-tuning framework named TuningGenie aimed at automating adjustment of parallel tasks to target platform. The framework works with source code of parallel software and performs source-to-source transformations by using facilities of a rule-based rewriting system. This approach significantly raises flexibility of proposed solution and enables changing computation structure of a tuned program in a declarative way. The framework’s architecture, lifecycle, offered toolset for optimization, demo examples and results of tuning of a computationally complex task of short-term meteorological forecasting are presented.

Results of an experiment, on which base a capacity estimation of cooperative 2×2 MIMO, MISO, and SIMO was obtained for high frequency radio channels for the following cases: 1) presence of the channel state information on the receiving side only, 2) presence of the channel state information on both receiving and transmitting side, 3) incomplete and/or inaccurate channel state information on the transmitting side. The experiment was carried out under typical for the real use conditions of time and frequency synchronization of the radio, connected to each antenna element.

Total cross sections for proton induced fission of {sup nat}Pb, {sup 209}Bi, {sup 232}Th, {sup 233}U, {sup 235}U, {sup 238}U, {sup 237}Np, and {sup 239}Pu nuclei were measured in the range 200-1000 MeV with an energy step of 100 MeV. The experiment was carried out at 1 GeV in a PNPI synchrocyclotron. Complementary fragments of the binary fission from a thin target were detected in coincidence by two parallel plate avalanche counters (PPAC) located close to the target. An assembly of the two PPACs and with the target in between them was placed directly into the beam, which provided a large solid angle acceptance. The beam monitoring system employed a scintillation counter telescope that was used for direct proton counting as well as for registration of the elastic pp-scattering events from the auxiliary (CH{sub 2}){sub n} target. The measured energy dependence of the total fission cross sections is presented. The results are compared with other available experimental data as well as with calculations in the frame of the cascade-evaporation model.

Regional forecasting is of great importance because of its potential for preventing economical and social consequences of natural and man-caused atmospheric pollution. A new non-standard approach and computational method is offered in this paper for the efficient solution for forecasting regional meteorological processes. The method replaces the Cauchy problem in the atmospheric model by a boundary-value problem and introduces a specific interpolation technique that has a number of advantages for the method to be computationally efficient. The model and method have been tested by the Hydrometeorological Centre of Ukraine and successfully applied in regional short- and middle-term weather forecasting for regions of Ukraine.

A new approach is proposed to the numerical solution of one-dimensional convection-diffusion equations that arise in modelling atmospheric processes and air pollution modelling. The technique is based on upstream-type difference approximations for first-order derivatives and non-standard difference approximations for second-order derivatives of convection-diffusion equations. This approach leads to the significant qualitative improvements in the numerical solutions behaviour. The relative contribution of convection and diffusion is directly incorporated into the corresponding numerical scheme in such a way that large spatial grids can be taken without affecting solution stability. The method is compared with the contemporary computational schemes for solving problems with severe internal and boundary gradients and is shown to be stable and computationally efficient. The results of a numerical experiment are given.