Індивідуально-авторські номінації осіб у поетичному словнику ХІХ століття. (Individual author's nomination of persons in the poetic vocabulary of the nineteenth century)

У статті здійснено аналіз авторських лексичних новотворів у поезії Т. Шевченка, П. Грабовського та Ю. Федьковича за частотністю та семантикою,проведен частиномовний розподіл новотворів письменників, визначено найбільш репрезентативні тематичні групи АЛН. (The article is devoted to analysis of author lexical new-formation by T. Shevchenko, P. Hrabovsky and Yu. Fedkovych according to frequency and semantics, new coined words’ distribution under their belonging to different parts of speech, defining of the most representative groups of ALN.

Electric field effects on magnetotransport properties of multiferroic Py/YMnO3/Pt heterostructures

We report on the exchange bias between antiferromagnetic and ferroelectric hexagonal YMnO3 epitaxial thin films sandwiched between a metallic electrode (Pt) and a soft ferromagnetic layer (Py). Anisotropic magnetoresistance measurements are performed to monitor the presence of an exchange bias field. When the heteroestructure is biased by an electric field, it turns out that the exchange bias field is suppressed. We discuss the dependence of the observed effect on the amplitude and polarity of the electric field. Particular attention is devoted to the role of current leakage across the ferroelectric layer.Comment: Accepted for publication in Philosophical Magazine Letters (Special issue on multiferroics

Surface morphology and magnetic anisotropy in (Ga,Mn)As

Atomic Force Microscopy and Grazing incidence X-ray diffraction measurements have revealed the presence of ripples aligned along the $[1\bar{1}0]$ direction on the surface of (Ga,Mn)As layers grown on GaAs(001) substrates and buffer layers, with periodicity of about 50 nm in all samples that have been studied. These samples show the strong symmetry breaking uniaxial magnetic anisotropy normally observed in such materials. We observe a clear correlation between the amplitude of the surface ripples and the strength of the uniaxial magnetic anisotropy component suggesting that these ripples might be the source of such anisotropy.Comment: 3 pages, 4 figures, 1 table. Replaced with published versio

Electric field control of exchange bias in multiferroic epitaxial heterostructures

The magnetic exchange bias between epitaxial thin films of the multiferroic (antiferromagnetic and ferroelectric) hexagonal YMnO3 oxide and a soft ferromagnetic (FM) layer is used to couple the magnetic response of the ferromagnetic layer to the magnetic state of the antiferromagnetic one. We will show that biasing the ferroelectric YMnO3 layer by an appropriate electric field allows modifying and controlling the magnetic exchange bias and subsequently the magnetotransport properties of the FM layer. This finding may contribute to pave the way towards a new generation of electric-field controlled spintronics devices.Comment: 15 pages, 5 figures, submitte

Research and development of laser engraving and material cutting machine from 3D printer

This article deals with the adjustment of a 3D printer for laser engraving and material cutting. The print head can be fitted with a solid laser diode module, which achieves a compact size while retaining its useful power. Two paths lead to the use of such a concept. It is possible to equip the existing print head with a module, which also brings a number of disadvantages such as, for example, the reduction of the printing space or the need for a suitable mounting design. A more elegant solution is to consider this in the design of a 3D printer and design a system to exchange the print heads for 3D printing and laser engraving. Such a solution allows full utilization of the workspace and simple installation of the effector for the required type of work. According to the installed power of the laser diode, it is possible not only to engrave but also cut material such as thin wood, veneer or acrylic glass. The use of such a machine is not only for graphic elements but for the creation of various stencils, boxes or simple models, which can be made up of plastic-burning pieces. The laser module is controlled by a driver, which is designed for the device. This is connected to a 3D printer control board. It is, therefore, necessary for the control board to have at least two pins, which can be controlled after adjusting the control firmware. Most laser modules are normally equipped with an adjustable lens, which is used to concentrate the focus of a laser for the given distance against the worktop. Thus, the modified 3D printer can perform its function as a multi-purpose CNC machine, while a basic platform similar for both devices is used.Web of Science281524

Investigation of the Arc-Anode Attachment Area by Utilizing a High-Speed Camera

The arc-anode attachment in the DC plasma arc influences power distribution in the plasma, a lifespan of anode and flow structure of plasma jet. A movement of the attachment and the surrounding plasma was directly observed by using a high-speed camera (max. 1,080,000 fps). The observations were compared with cathode-anode voltage measurements (sample rate 80 MHz). We have directly measured the average velocity of the attachments and hydrodynamic waves above them, as well as the characteristic dwell times and dwell frequencies of the attachments

Modal analysis of the fgm beam-like structures with effect of the thermal axial force

The modal analysis of the FGM beam-like actuator is presented, where effects of the thermal axial force and the shear force are considered. The temperature load is assumed to be lower as the critical buckling temperature. The longitudinal variation of material properties has been assumed which can be caused by the varying constituent’s volume fraction and the temperature dependence of the constituent’s material properties. Our new FGM beam finite element has been used in the proposed analysis. An influence of the material properties variation and the thermal axial forces on the actuator eigenfrequency and eigenform has been studied and discussed

Principal spectra describing magnetooptic permittivity tensor in cubic crystals

We provide unified phenomenological description of magnetooptic effects being linear and quadratic in magnetization. The description is based on few principal spectra, describing elements of permittivity tensor up to the second order in magnetization. Each permittivity tensor element for any magnetization direction and any sample surface orientation is simply determined by weighted summation of the principal spectra, where weights are given by crystallographic and magnetization orientations. The number of principal spectra depends on the symmetry of the crystal. In cubic crystals owning point symmetry we need only four principal spectra. Here, the principal spectra are expressed by ab-initio calculations for bcc Fe, fcc Co and fcc Ni in optical range as well as in hard and soft x-ray energy range, i.e. at the 2p- and 3p-edges. We also express principal spectra analytically using modified Kubo formula

Quadratic-in-magnetization permittivity and conductivity tensor in cubic crystals

We present diagonal and off-diagonal elements of the permittivity and conductivity tensor up to the second order in magnetization for cubic crystals. We express all tensor elements as a function of a general sample orientation, for arbitrary magnetization direction and for (001), (011) and (111) surface orientations. Finally, we discuss, how to extract values of quadratic elements G of the second order permittivity tensors for different sample surface orientations from both experiment and ab-initio calculations