East European Journal of Physics https://periodicals.karazin.ua/eejp <p>International peer-reviewed journal devoted to experimental and theoretical research on the nuclear physics, cosmic rays and particles, high-energy physics, solid state physics, plasma physics and controlled thermonuclear fusion, physics of charged particle beams, plasma electronics, radiation materials science, physics of thin films, condensed matter physics, functional materials and coatings, technical thermophysics and industrial power,&nbsp;medical physics and physical technologies in an interdisciplinary context.</p> <p><strong>East European Journal of Physics</strong> <strong>has been selected for coverage in Clarivate Analytics products and services.&nbsp;Beginning with 2017 it will be indexed and abstracted in: "Emerging Sources Citation Index"(ESCI).</strong></p> en-US <p>Authors who publish with this journal agree to the following terms:<br><br></p> <ol type="a"> <ul> <li class="show">Authors retain copyright and grant the journal right of first publication with the work simultaneously licensed under a&nbsp;<a href="http://creativecommons.org/licenses/by/4.0/" target="_new">Creative Commons Attribution License</a>&nbsp;that allows others to share the work with an acknowledgement of the work's authorship and initial publication in this journal.</li> </ul> </ol> <ol type="a"> <ul> <li class="show">Authors are able to enter into separate, additional contractual arrangements for the non-exclusive distribution of the journal's published version of the work (e.g., post it to an institutional repository or publish it in a book), with an acknowledgement of its initial publication in this journal.</li> </ul> </ol> <ol type="a"> <ul> <li class="show">Authors are permitted and encouraged to post their work online (e.g., in institutional repositories or on their website) prior to and during the submission process, as it can lead to productive exchanges, as well as earlier and greater citation of published work (See&nbsp;<a href="http://opcit.eprints.org/oacitation-biblio.html" target="_new">The Effect of Open Access</a>).</li> </ul> </ol> serhii.hirnyk@karazin.ua (Serhii Hirnyk) serhii.hirnyk@karazin.ua (Serhii Hirnyk) Tue, 10 Dec 2019 12:27:02 +0200 OJS http://blogs.law.harvard.edu/tech/rss 60 Model of Forming Isotropic and Anisotropic Graphite Under High Temperatures and Fluences Neutron Irradiation https://periodicals.karazin.ua/eejp/article/view/14693 <p>A model is proposed for describing the shape change of isotropic and anisotropic graphite under the influence of high temperatures and high neutron radiation fluences. The model is based on a new approach, which uses the following provisions: description of the near-pore neighborhood in graphite as a solid solution using the theory of phase transformations of the first kind; consideration of a new phase as a spheroidal pore of small eccentricity, flattened along the direction of greatest stress; taking into account the clustering of carbon atoms at fluences of more than . The graphite non-isotropy is characterized by different pore sizes, different diffusion coefficients, the lengths of the paths of graphite atoms along and across volume of the sample, which in turn depend on the temperature of the sample. It is proposed that the initial element on the basis of which a new phase will be formed is the spheroidal pore of small eccentricity, flattened along the direction of the highest tension. A kinetic equation that describes the diffusion of pores under the influence of high temperatures and intense neutron fluxes is obtained. Initially, the pores are in a field of predetermined stresses oriented along and across the sample. The contribution of diffusion processes is due to the term proportional to the pore distribution function in the sample, and the effect of the neutron flux is described by an additional term in the kinetic equation. The obtained kinetic equation for anisotropic graphite can be transformed for isotropic graphite. For isotropic and anisotropic graphite, model solutions have been obtained that characterize the change in its volume with time under the influence of a neutron flux and high temperature. It is shown that the magnitude of the change in the relative volume of reactor graphite for isotropic graphite exceeds a similar value for anisotropic graphite. Theoretical confirmation of the laws governing the swelling of anisotropic graphites under the influence of large neutron fluences and in the high-temperature field, previously obtained by other authors, is obtained: longitudinal compression of anisotropic graphite samples corresponds to a change in the linear dimensions of isotropic graphites; the transverse compression of anisotropic graphite samples is less than the change in the longitudinal linear dimensions of isotropic graphites.</p> Mykola P. Odeychuk, Victor I. Tkachenko, Leonid A. Bulavin, Boris V. Borts, Stella I. Skoromnaya ##submission.copyrightStatement## https://periodicals.karazin.ua/eejp/article/view/14693 Mon, 25 Nov 2019 00:00:00 +0200 The Stability of a Rotating and Heated From Below Horizontal Cylindrical Layer of a Viscous, Incompressible Liquid with Free Boundaries https://periodicals.karazin.ua/eejp/article/view/14695 <p>The stability of a rotating and heated from below horizontal cylindrical layer of a viscous, incompressible liquid with free boundaries was theoretically investigated. Neglecting the centrifugal forces, the equations of motion, thermal conductivity and incompressibility of the liquid were written, from which the well-known dispersion equation was derived in the linear approximation. The stability of a rotating cylindrical volume of a liquid with no heating from below was considered, provided that the temperature difference between the horizontal boundaries of the liquid was fixed and equal to zero. It was demonstrated, that with no heating from below the temperature difference between the horizontal boundaries of the rotating liquid was not fixed and not maintained from the outside, the perturbed liquid temperature would increase, but its final value did not exceed the phase transition temperature. The obtained result was used to explain the heating of water in Ranque – Hilsch vortex tubes. It was concluded that the water heating in Ranque -Hilsch tubes should be considered as the inverse Rayleigh problem, in which the temperature gradient can be determined from the known distribution of velocities inside the volume. The stability of a rotating cylindrical volume of a liquid when heated from below was analyzed. It was demonstrated, that the value of the specified temperature difference at cylinder boundaries, as well as the initial rate of its variation, determine the final heating temperature of the liquid. A comparison of the proposed theory and experimental data for water heating shows their good qualitative and quantitative agreement.</p> Oksana L. Andreeva, Leonid A. Bulavin, Viktor I. Tkachenko ##submission.copyrightStatement## https://periodicals.karazin.ua/eejp/article/view/14695 Mon, 25 Nov 2019 00:00:00 +0200 Phase Transitions in Convection https://periodicals.karazin.ua/eejp/article/view/14696 <p>The paper presents the results of the study of the models of convective instability near its threshold of thin layers of liquid and gas bounded by poorly conducting walls. These models single out one spatial scale of interaction, leaving the possibility for the evolution of the system to choose the symmetry character. This is due to the fact that the conditions for the realization of the modes of convective instability near the threshold are chosen. All spatial perturbations of the same spatial scale, but of different orientations, interact with each other. It turned out that the presence of minima of the interaction potential of the Proctor-Sivashinsky equation modes, the absolute value of the wave number vectors of which is unchanged, determines the choice of symmetry and, accordingly, the characteristics of the spatial structure. In the case of a more realistic model of convection described by the Proctor-Sivashinsky equation, it was possible to observe both the first-order phase transition and the second-order phase transition and detect the form of the state function, which is responsible for the topology of the resulting convective structures:&nbsp; metastable rolls and stable square cells. In this paper, it is shown that the nature of the structural-phase transition in a liquid when taking into account the dependence of viscosity on temperature in the Proctor-Sivashinsky model is similar to the case of the absence of such a dependence. The transition time turns out to be the same, despite the fact that a different structure is formed - hexagonal convective cells. As in the Swift-Hohenberg model, a hard mode for the formation of hexagonal cells in a gas medium is possible only for a sufficiently noticeable dependence of its viscosity on temperature. The phase transition times are inversely proportional to the difference in the values of this function for two consecutive states. A similar description of phase transitions did not use phenomenological approaches and various speculative considerations, which allows for a closer look at the nature of transients.</p> Ivan V. Gushchin, Volodymyr M. Kuklin, Eugen V. Poklonskiy ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 https://periodicals.karazin.ua/eejp/article/view/14696 Mon, 25 Nov 2019 00:00:00 +0200 On Frequency and Spatial Periodicity of the Waves of the Anomalous Amplitude in the Ocean https://periodicals.karazin.ua/eejp/article/view/14697 <p>The paper shows that the waves of anomalous amplitude are long-lived formations. They drift in the direction of the wave motion with the group velocity of the wave packet, which is half the phase velocity of the main wave. The swing of the wave (the distance from the hump to the trough) of the anomalous amplitude is more than three times the average value of the sweep of the wave motion. The modulation instability of this wave form a perturbation spectrum, the energy of which is twice the energy of the main wave in the developed process mode. The spatial size of the wave packet practically does not change, the amplitude of the swing in the maximum first increases, then gradually decreases. The number of such waves in areas of strong wind exposure is much larger than the statistics of random interference processes allow. This is due to the influence of the main wave (its amplitude remains noticeably greater than the amplitudes of each of the modes of the wave packet) on the behavior of each pair of modes from the wave packet of the perturbation. In the laboratory system, the duration of the anomalous wave coincides qualitatively with the time of existence of the Peregrin autowave. Although the Peregrin autowave corresponds to a different physical reality, where the dispersion of the wave is weak. Gravitational surface waves have a strong dispersion, and the NSE equation in this case is noticeably modified. However, in rest system of the wave packet (moving relative to the laboratory system) the abnormal amplitude wave lifetime is much longer. The distance that the wave packet travels with a persisting anomalous sweep is at least equal to several hundred wavelengths and can reach hundreds of kilometers. A simple calculation of such waves by means of space monitoring due to the small viewing area (frame) may be inaccurate. Once formed, such waves are able to drift over considerable distances. However, they may well get into the next frame of view. That is, estimates of the number of such waves can be overestimated.</p> Volodymyr M. Kuklin, Eugen V. Poklonskiy ##submission.copyrightStatement## https://periodicals.karazin.ua/eejp/article/view/14697 Mon, 25 Nov 2019 00:00:00 +0200 Effect of the Oscillating Electric Field Due to the Oscillating Electric Dipole on Raman Lines https://periodicals.karazin.ua/eejp/article/view/14694 <p>Raman Effect is the measurement of the intensity and wavelength of the inelastically scattered radiation that falls on a molecule. The electric field of the incident radiation polarizes the molecule on which it falls and this leads to the creation of an oscillating dipole. The incident polarized laser light is inelastically scattered by the molecular sample. The scattered light contains modified wavelengths called the Stokes and anti-Stokes lines or wavelengths. The oscillating electric dipole, created by the incident radiation, creates an oscillating electric field around it. Since the oscillating electric field of the incident radiation creates an oscillating electric dipole that create an oscillating electric field around it, it was surmised that this oscillating electric field can affect the frequency of vibration or oscillation of the oscillating electric dipole that produces it. This novel effect will change the frequency (frequencies) of the scattered radiation resulting in Stokes and anti-Stokes lines with modified frequencies. This theoretical research and its importance can be understood like this. For instance, if there are two cells or molecules, side by side, in which one is a healthy cell and the other is cancerous, or two different types of molecules are sitting side by side, this types of scattering should be able to distinguish one from the other since the Stokes and anti-Stokes lines from the two molecules will not be identical. Thus, the incident radiation of angular frequency ω<sub>1</sub> polarizes the charges of the molecule on which it falls and this leads to the creation of an oscillating dipole of frequency ω<sub>2</sub>. The oscillating dipole creates an oscillating electric field that can create additional frequency of the oscillating dipole that created it, and let this be ω<sub>D</sub>. Then the Raman lines can have frequencies (ω<sub>1</sub>+ω<sub>2</sub>+ω<sub>D</sub>), (ω<sub>1</sub>+ω<sub>2</sub>-ω<sub>D</sub>), (ω<sub>1</sub>-ω<sub>2</sub>+ω<sub>D</sub>), and (ω<sub>1</sub>-ω<sub>2</sub>-ω<sub>D</sub>). Depending on the relative magnitudes of ω<sub>2</sub> and ω<sub>D</sub>, Raman lines will be designated as Stokes and Anti-Stokes lines. Due to the law of conservation of energy, ω<sub>D&nbsp;</sub>will be less than ω<sub>2</sub> since an oscillating dipole cannot create field of frequency more than its own frequency. Hence the frequencies (ω<sub>1</sub>-ω<sub>2</sub>+ω<sub>D</sub>) and (ω<sub>1</sub>-ω<sub>2</sub>-ω<sub>D</sub>) correspond to Stokes lines, and frequencies. (ω<sub>1</sub>+ω<sub>2</sub>+ω<sub>D</sub>) and (ω<sub>1</sub>+ω<sub>2</sub>‑ω<sub>D</sub>) will correspond to Anti-Stokes lines. Calculations for Stokes and Anti-stokes lines have been done for some molecules, namely Ammonia compound (NH<sub>3</sub>), Nitrousoxide compound (N<sub>2</sub>O), Water (H<sub>2</sub>O), Sulphur dioxide compound (SO<sub>2</sub>), Ozone compound (O<sub>3</sub>). Calculations have also been done for compounds containing carbon, such as Dichloromethane compound (CH<sub>4</sub>Cl<sub>2</sub>), Formic acid compound (CH<sub>2</sub>O<sub>2</sub>), Methanol compound (CH<sub>4</sub>O), Benzene compound (C<sub>6</sub>H<sub>6</sub>), Propane compound (C<sub>3</sub>H<sub>8</sub>), and Carbonyl chloride compound (Cl<sub>2</sub>CO). The theory developed predicts new phenomena of getting Stokes and anti-Stokes lines with modified wavelengths which have not been observed experimentally as of to-day.</p> Khanna M. Kapil, Murei K. Gilbert ##submission.copyrightStatement## https://periodicals.karazin.ua/eejp/article/view/14694 Sun, 24 Nov 2019 00:00:00 +0200 Three-Step Resonance Energy Transfer in Insulin Amyloid Fibrils https://periodicals.karazin.ua/eejp/article/view/14723 <p>The applicability of the three-step Förster resonance energy transfer (FRET) to detection of insulin amyloid fibrils was evaluated, using the chromophore system, containing Thioflavin T (ThT), 4-dimethylaminochalcone (DMC), and two squaraine dyes, referred to here as SQ1 and SQ4. The mediator chromophore DMC was found to enhance the fluorescence intensity of the terminal acceptor, SQ1, excited at 440 nm (at the absorption maximum of the principal donor, ThT), in fibrillar insulin compared to the system without DMC, providing the evidence for the cascade energy transfer in the chain ThT→DMC→SQ4→SQ1. Furthermore, the resulting Stokes shift in the four-chromophore system was 240 nm, as compared to 45 nm for the fibril-bound ThT, suggesting that higher signal-to-noise ratio is the advantage of amyloid fibril detection by multistep FRET. The maximum efficiencies of energy transfer in the insulin fibrils estimated from the quenching of the donor fluorescence in the presence of acceptor for the donor-acceptor pairs ThT-DMC, DMC-SQ4 and SQ4-SQ1 were 40%, 60% and 30% respectively, while negligible FRET occurred in the non-fibrillized protein. The most pronounced differences between fibrillar and non-fibrillized insulin were observed in the 3D fluorescence spectra. Specifically, two intensive spots centered at the emission wavelengths ~ 650 nm (SQ4) and ~ 685 nm (SQ1) were revealed at the excitation wavelength ~ 440 nm in the 3D patterns of insulin amyloid aggregates. In contrast, in the case of the non-fibrillized protein, the barely noticeable spots centered at the same wavelengths, as well as higher fluorescence intensities at the excitation above 550 nm were observed, suggesting the predominant impact of the direct excitation of SQ1 and SQ4 on their fluorescence responses. The inter-chromophore distances calculated from the experimental values of the energy transfer efficiency assuming the isotropic rotation of the dyes, were found to be 2.4, 4.5 and 4.3 nm for the ThT-DMC, DMC-SQ4 and SQ4-SQ1 pairs, respectively, revealing the different fibril binding sites for the examined dyes. The quantum-chemical calculations and simple docking studies provided evidence for the SQ1, SQ4 and ThT, DMC binding to the wet and dry interface of the insulin amyloid protofilament, respectively. The dye-protein complexes are likely to be stabilized by the hydrophobic, van der Waals, aromatic and electrostatic interactions. In summary, the above technique based on the multistep FRET can be employed for the identification and characterization of amyloid fibrils in vitro along with the classical ThT assay, allowing the increase of the amyloid detection sensitivity and lowering the probability of the pseudo-positive result.&nbsp; The applicability of the multistep FRET for amyloid visualization in vivo can be also tested by the involvement of the near-infrared fluorescent dyes to the cascade.</p> Uliana Tarabara, Mykhailo Shchuka, Kateryna Vus, Olga Zhytniakivska, Valeriya Trusova, Galyna Gorbenko, Nikolai Gadjev, Todor Deligeorgiev ##submission.copyrightStatement## https://periodicals.karazin.ua/eejp/article/view/14723 Tue, 26 Nov 2019 00:00:00 +0200 Effect of the Transatmospheric Sun Electromagnetic Radiation, Simulated Laboratory, on the Mechanical Properties of the KAPTON H Type Polyimide Films https://periodicals.karazin.ua/eejp/article/view/14724 <p>The mechanical properties (limit of forced elasticity, fracture stress, total deformation to failure and its components) of a 75 mm-thick polyimide film of kapton H type under uniaxial tension conditions at 293 K after exposure to the outer space factors were studied. The electromagnetic radiation of the transatmospheric Sun in the wavelength range of 250-2500 nm (EMRS) for 100 hours and vacuum ultraviolet (VUV) and ultra soft x-ray (USX) radiation in the range of 1.24-170 nm – for 100 and 500 hours were simulated under laboratory conditions. The effect of separate exposure in each of the wavelength ranges was investigated. It was found that after irradiation in the both wavelength ranges the films remained in a forced-elastic state. The tension diagrams, like in the initial state, have two stages. The contributions of the elastic, irreversible and highly elastic (delayed and reversible at test temperature) components to the total deformation to failure were determined. It was found that the limit of forced elasticity increased after irradiation both with EMRS, and with VUV and USX radiation. In this case an increase in the limit of the forced elasticity under the influence of EMRS was caused by heating of the film in the course of irradiation, and under the influence of VUV and USX radiation – by radiation effects. The fracture stress and total deformation to failure change weakly and only under the influence of VUV and USX radiation. With changing the duration of exposure to VUV and USX radiation (100 or 500 hours), the fracture stress and the total deformation to failure change non-monotonously. The negative consequence of exposure to VUV and USX radiation is the contribution values redistribution of the individual components of the total deformation to failure. VUV and USX radiation within 500 hours leads to a halving of the contribution of elastic deformation, which is reversible at deformation temperature.</p> Viktory A. Lototskaya, Leonid F. Yakovenko, Evgeniy N. Aleksenko, Ivan P. Zaritskiy, Yuriy S. Doronin, Anna A. Tkachenko, Nikolay I. Velichko, Vyacheslav V. Abraimov, Wen Zhu Shao ##submission.copyrightStatement## https://periodicals.karazin.ua/eejp/article/view/14724 Tue, 26 Nov 2019 00:00:00 +0200 Digital Triggering Device and Generator of Starting Pulses for Ignition of Spark Gaps of REB Accelerator “TEMP” https://periodicals.karazin.ua/eejp/article/view/14725 <p>To ensure the controllability and high noise immunity while measuring the characteristics of the accelerators of relativistic electron beams (REB) “TEMP”, and parameters of the processes in them, triggering devices with galvanic isolation of input and output circuits, allowing to set up the pulse delays in the range from 1 μs to tens of milliseconds, have been developed. When they are used, the effect of loop currents, which flow in the common ground circuits and affect the operation of the measuring equipment, is eliminated. To synchronize the operation of the REB accelerator “TEMP” a triggering device was developed and assembled. It was assembled from blocks produced on the up-to-date elemental base and is a complete functional product. The triggering device comprises a trigger block and delay units. The trigger block is developed on the basis of an AND - NOT chip and a multivibrator. The delay units are built on single-shot vibrators K155AG1 and differ in the value of adjustable delays, which are determined by the external elements R and C, connected to the multivibrator. Unfortunately, in case the millisecond delays are set up, the pulse drop on the multivibrator is not stable. Therefore, a digital triggering device was developed. The digital triggering device is built on the basis of digital microcircuits and consists of the following blocks: binary-decimal counters, decoders, and one oscillator with quartz frequency stabilization, which is common to all four channels. It contains four identical channels with delay adjustment from one microsecond to one hundred milliseconds. Such a pattern of the circuit allows, if necessary, adding channels for starting other units. Pulse signals of the triggering device are fed to the ignitor unit of the spark-gaps. A pulse generator for igniting the spark-gaps of the REB accelerator “TEMP” has been developed. A generator, designed to control the spark gaps ignition in the High Voltage Pulse Generator (HVPG) and spark gaps ignition in the magnetic systems, which are used in switching systems of the capacitor banks with the energy &nbsp;of 60 ¸ 150 kJ, has been described. The generator provides voltage pulses with the amplitude of up to 20 kV, at the current in the short circuit mode of 5 A, the pulse duration of the first half wave of 12 μs, and the pulse repetition frequency (PRF) of not more than 10&nbsp;Hz.</p> Aleksey B. Batrakov, Eugeniy G. Glushko, Andrey A. Zinchenko, Yuriy F. Lonin, Anatoliy G. Ponomarev, Sergei I. Fedotov ##submission.copyrightStatement## https://periodicals.karazin.ua/eejp/article/view/14725 Tue, 26 Nov 2019 00:00:00 +0200 Spatial Resolution and Measurement Accuracy of the Ultrasound Diagnostic System at Acoustic Remote Palpation Using High Intensity Focusing Ultrasound https://periodicals.karazin.ua/eejp/article/view/14753 <p>In this work the spatial resolution and measurement accuracy of the ultrasound diagnostic system at acoustic remote palpation (ARP) using high-intensity focusing ultrasound (HIFU) are studied theoretically and experimentally. A physical model is proposed, which describes the specific features of ARP taking into account the remote nature of ultrasound Doppler probing of the soft tissues local movements, which are caused by the radiation pressure of HIFU pulse. Taking into account the accepted simplifying assumptions it is shown that the model conclusions are in a good agreement with the results of the experiments on measuring the value of displacements under the influence of HIFU. In particular, the nontrivial dependence of the value of displacements, measured by the Doppler method, on the probing depth and focusing degree of the incident and scattered wave beams, is proved. An experimental study was performed on the transverse resolution at ARP in the case of probing of the medium with Young's modulus irregularity, as well as on the influence of noise and interference on the measurement accuracy and resolution. It is concluded, that the transverse resolution at ARP is determined by the parameters of the local area of the movement, and can be significantly higher than the transverse intrinsic resolution of the ultrasound system at B-mode of diagnostics. The obtained results indicate that ARP is a promising method for monitoring the process of the soft tissues thermal ablation, when HIFU is used.</p> Evgen A. Barannik, Viktor I. Pupchenko, Anatoliy I. Marusenko, Oleksiy V. Knyazyev, Igor M. Tsybin, Aleksandr E. Berkovich ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 https://periodicals.karazin.ua/eejp/article/view/14753 Mon, 02 Dec 2019 00:00:00 +0200 The Threshold of Detection of Fission Materials by ZnWO4 and Bi4Ge3O12 Scintillation Detectors https://periodicals.karazin.ua/eejp/article/view/14756 <p>In the present work we found the maximum discovery distance for <sup>239</sup>Pu-Be source using the detectors based on ZWO (ZnWO<sub>4</sub>) and BGO (Bi<sub>4</sub>Ge<sub>3</sub>O<sub>12</sub>) oxide scintillators. Detection distance was defined by using the radiation monitoring system ”PORTAL”. This research gives us data for estimation of the contribution of low-energy cascade gamma quanta CGQ. The CGQ emitted by excited scintillator nuclei defined the effective discovery distance of the fast neutrons source. The maximum detection distance was obtained with PMT in a single-photon counting mode. The maximum discovery distance for a BGO scintillator of size Ø40×40 mm – 38 cm, ZWO scintillator of size Ø52×40 mm – 54 cm, with reliability about 0.001. The results of the experiment on the ZWO scintillator can be explained by the registration of additional gamma quanta from the inelastic scattering reaction and the CGQ arising from resonant neutron capture region. This two mechanisms further lead to increase the sensitivity of the detector and increase the detection distance of the monitoring system. The key features of the monitoring system are: ZWO oxide scintillator, wide band measuring path, utilize PMT in single photon mode. The obtained detection distance was about 1.4 times higher in comparison with the spectrometric recording mode and 1.9 times higher in values of efficiency. Our results demonstrate the advantages of the ZWO scintillator compared to the BGO and demonstrate the possibility of using the resonant capture mechanism by ZWO detector nuclei to increase the fast neutrons sensitivity. The resonance capture mechanism increase sensitivity and maximum detection distance of the monitoring system. The low-energy gamma-quanta, which discharge of compound nuclei, are substantially suppressed in comparison with the classic spectrometric recording mode.</p> Gennadiy M. Onyshchenko, Volodymyr D. Ryzhikov, Ivan I. Yakymenko, Oleksandr P. Shchus’ ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 https://periodicals.karazin.ua/eejp/article/view/14756 Tue, 03 Dec 2019 00:00:00 +0200 It Should Be Remembered Before Peter Kapitsa Our Laboratory Was the First and sole in the USSR https://periodicals.karazin.ua/eejp/article/view/14757 <p>"If I were offered to declare the names of only two physicists who were most famous in Ukrainian science, I would call the theorist L.D. Landau and experimenter L.V. Shubnikov"</p> <p>Academician of NAS of Ukraine OI Akhiezer</p> Alla Tan'shyna ##submission.copyrightStatement## http://creativecommons.org/licenses/by/4.0 https://periodicals.karazin.ua/eejp/article/view/14757 Tue, 03 Dec 2019 00:00:00 +0200