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Том 45, № 6 (2018)
- Год: 2018
- Статей: 6
- URL: https://journals.rcsi.science/1068-3356/issue/view/14132
Article
Study of the Mechanism of the Autowave Structure Formation at the Reaction Front
Аннотация
A qualitative mechanism of the formation of wave structures at the reaction front is proposed. It is assumed that the structures are formed as a result of the interaction of two subsystems, one of which is responsible for the front formation, and the other is responsible for the formation of structures themselves. Three models are considered; two-dimensional analogues of concentric and spiral waves are numerically demonstrated in each. Fitzhugh–Nagumo, Fisher–Kolmogorov–Petrovskii–Piscounov (Fisher–KPP), and Oregonator models were used as subsystems.
165-169
Features of Copper Vapor Laser Emission Excited by Pulse-Periodic HF Discharge
Аннотация
The results of numerical studies of pulsed radiation of the induction copper vapor laser are presented. The laser is excited by trains of high-frequency (10–70 MHz) electric current oscillations. Trains follow one after another with a frequency in 2–17 kHz. The features and variety of obtained laser radiation pulse shapes and their applicability to diagnostic purposes and other practical problems are discussed.
170-175
Tomography Imaging Taking Into Account Spectral Information
Аннотация
A technique for increasing the information content of tomography imaging by using additional information about radiation absorption at various energies is considered. The positive effect of this technique is the determination of the distribution of various components over the sample volume. The technique differs in the fact that initial radiograms taking into account spectral information are obtained for one scanning without tuning irradiation conditions when using a spectrally sensitive matrix detector.
176-181
Growth and Study of Scintillation Properties of Orthovanadate Crystals Ca:GdVO4 and Ca:YVO4
Аннотация
New scintillation orthovanadate crystals Ca:GdVO4 and Ca:YVO4 featuring intrinsic luminescence are grown. The spectra of pulsed cathodoluminescence of new scintillators and their luminescence decay time are studied. Using γ-rays with an energy of 662 keV from the 137Cs source, total absorption spectra (so-called photopeaks) for new orthovanadate crystals are measured. It is shown that the light yield of Ca:YVO4 and Ca:GdVO4 crystals is 28100 photon/MeV and 14000 photon/MeV, respectively.
182-186
Low-Frequency Stimulated Raman Scattering on Acoustic Vibrations of Dielectric Nanospheres in Aqueous Suspension
Аннотация
A low-frequency SRS (LFSRS) signal is detected at a certain dielectric nanoparticle (latex spheres) concentration in an aqueous suspension. The SRS line shift is close to its estimate by the “transverse” hypersound speed in latex.
187-189
Development of Microdosimeters for Beam Therapy Based on Superpure Tetramethylsilane and Testing of its Conductivity
Аннотация
A setup version for producing samples of tetramethylsilane (TMS) and its cleaning from electronegative impurities is developed and tested. Purified TMS can be used in microdosimeters when operating on therapeutic accelerators in planning beam therapy. A monitoring system of the degree of TMS purity by the conductivity and free electron yield is described. A TMS-based microdosimeter can be used in combination with a television-type detector to improve the absorbed dose measurement accuracy in the Bragg peak region.
190-194