Conversion of Magnus salt into diamminedichloroplatinum(II) isomers in aqueous solution

The conditions inducing conversion of Magnus salt into diamminedichloroplatinum(II) isomers were studied. Syntheses of cis-diamminedichloroplatinum(II) and trans-diamminedichloroplatinum(II), which are used to prepare potassium or ammonium amminetrichloroplatinate(II), are described. The identity and structure of diamminedichloroplatinum(II) isomers were verified by elemental analysis, X-ray powder diffraction, and IR and UV spectroscopy. A workflow for preparing potassium or ammonium amminetrichloroplatinate(II) from diamminedichloroplatinum(II) isomers was developed. This workflow appreciably increases the product yield due to the return of unused Magnus salt to the main synthesis flow.     

Application of nuclear emulsion for search of light dark matter

One of the candidates for dark matter particles is the heavy photon. The experiment on the search for these particles using nuclear emulsions irradiated in a positron beam with an energy of 32 GeV is described. Methodical studies for estimating the efficiency of the search for electronpositron pairs and the effective mass determination accuracy are performed.     

The acoustic field of a high-frequency source moving in a waveguide

The acoustic field of a source moving at a subsonic velocity in a regular waveguide with perfectly reflecting boundaries is considered. The acceleration of the source is assumed to be small. In a moving coordinate system, the asymptotics of the wave field is obtained. This asymptotics is inapplicable near the critical cross sections, for which the Doppler frequency of the source coincides with the frequency of the waveguide mode under consideration. It is demonstrated that, in this case, the wave field can be represented locally by a special type of integral, which is analyzed by the saddle-point method.Translated fromZapiski Nauchnykh Seminarov POMI, Vol. 239, 1997, pp. 71–78.This work was supported in part by the Russian Foundation for Basic Research under grant 95-01-01285a.     

Search for superheavy elements in galactic cosmic rays

The charge distribution of approximately 6000 nuclei with charge numbers above 55 in galactic cosmic rays has been obtained in the OLIMPIYA project. Three superheavy nuclei with the charge numbers in the range 105 < Z < 130 have been detected. The regression analysis has provided a more accurate estimate of the charge number of one of these nuclei (119 _?6 ⁺¹⁰ with a probability of 95%). Such nuclei should form stability islands. Their detection in nature confirms theoretical predictions and justifies efforts for their synthesis under terrestrial conditions. The model calculations performed in this work possibly can explain the results of some experiments on the investigation of the charge composition of cosmic rays in which particles with charge numbers in the range 94 < Z < 100 were detected (they cannot enter into the composition of primary cosmic radiation because their lifetime is very short). The calculations indicate that events with Z > 92 are due to the fragmentation of heavier nuclei from the stability island, rather than to methodical inaccuracies or fault of instruments. Several such events have been revealed. Thus, the track method makes it possible to obtain the results very important for understanding of the physical picture of the world. The results obtained within the OLIMPIYA project show that the study of tracks of galactic cosmic rays in olivine crystals from meteorites opens new capabilities for the investigation of fluxes and spectra in cosmic rays in the region of heavy and superheavy nuclei.     

Features of Registration of Accelerated Heavy Ions by Phosphate Glass Detectors at Different Temperatures

Journal of Experimental and Theoretical Physics - The characteristics of heavy ion tracks in phosphate glasses after irradiation under various temperature conditions are presented. Calibration...     

Evaluation of the Thermodynamic Efficiency of Solid-State Coolers and Generators Based on the Multicaloric Effect

Technical Physics - The efficiency of using the multicaloric effect (μCE) in solid-state cooling systems is investigated and compared with single caloric effects. The proposed approach is...     

Stability of small radial oscillations of a spherical layer of liquid

An isothermal spherical layer of a viscoelastic liquid described by the one-parameter Maxwell model is considered. When the model parameter is taken equal to zero, a model of a purely viscous Newtonian fluid is obtained. The stability of the spherical layer of liquid with respect to small radial perturbations of the velocity and pressure is investigated for both types of liquids. Leningrad. Translated from Izvestiya Akademii Nauk SSSR, Mekhanika Zhidkosti i Gaza, No. 5, pp. 170–171, September–October, 1988.     

Detecting galactic cosmic ray transuranium nuclei in olivine crystals from meteorites

Results from the experimental search for and identification of tracks from the superheavy and transuranium nuclei of galactic cosmic rays in pallacite olivine crystals, conducted as part of project OLIMPIA [1], are presented. To date, 170 crystals from Marjalahti and Eagle Station pallacites have been processed and 6800 tracks corresponding to nuclei with charges Z > 55 have been found; 45 of these are from nuclei with charges of 88 < Z < 92 and three super-long ones were produced by nuclei with Z > 105. The charge of one of these nuclei is estimated in the first approximation as Z = 119(+10,?6). Our data confirm the hypothesis of islands of stability for natural trans-Fermi nuclei.     

Search for the νμ → ντ oscillation with the OPERA hybrid detector

This work reviews the status of the international OPERA experiment aimed at searching for the ν_μ → ν_τ oscillation. Development of the emulsion techniques in the preceding DONUT and CHORUS experiments is described. A brief overview of the NOMAD experiment is given, in which properties of ν_τ interactions were thoroughly investigated. Characteristics of the CERN-Gran Sasso (CNGS) neutrino beam are given, the structure of the OPERA hybrid detector and the functions of its subsystems are considered, and the automatic emulsion scanning technique is briefly reviewed. Uncertainties in reconstruction of event parameters using the electronic and emulsion detectors are discussed and the procedure adopted in the experiment for identification of ν_τ interactions is described. The main sources of background in the search for ν_μ → ν_τ oscillation are considered. Topologies of the first two ν_τ candidates observed in the OPERA emulsion detector are presented. Possibilities of increasing the ν_τ interaction selection efficiency using multidimensional criteria are briefly discussed.     

Boundary Behavior in a Stolz Angle of Analytic Functions on the Disk

In this paper, we study the behavior of analytic functions (on the disk) in a Stolz angle. In particular, we prove assertions of the type of the Hardy--Littlewood theorem and obtain estimates for the growth of functions in a Stolz angle.