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In this paper, microwave characterizations and phase-shifting applications of electrophoretically deposited thick films and sol-gel derived thin films of Barium Strontium Titanate (BST) are presented. Capacitors fabricated using Ba 0.7 Sr 0.3 TiO 3 films prepared by electrophoretic deposition (EPD) on platinum foils and sol-gel technique on platinized Si and SiO 2 demonstrate a maximum tunability of 49%, 29%, and 33%, respectively. The nominal capacitance and the microwave loss tangent are obtained from 500 MHz to 6 GHz. The three different BST films are designed to fabricate phase shifters. The total phase shift divided by the maximum insertion is 10°/dB higher in phase shifters developed with thin films on SiO 2 than in thick films. The linearity of the RF phase shifters using an input power from −20 dBm to 4 dBm is also analyzed. The linearity of the RF phase shifters using an input power from −20 dBm to 4 dBm is also analyzed. For the first time, the two methods of film deposition are directly compared in microwave applications. published

The results of the experimental study of the regularities of processes in the elements of thermochemical fuel treatment through the utilization of secondary energy resources have been presented in the article. As criteria for evaluating the energy efficiency of the processes of thermochemical treatment of hydrocarbon fuels have been proposed: the coefficient of increasing the calorific value of the base fuel and the energy utilization coefficient. Criteria for evaluating the energy efficiency of the processes of thermochemical treatment of hydrocarbon fuels have been proposed. The scheme of the experimental stand and the research methodology have been represented. The results of a comprehensive analysis of the influence of the process parameters of thermochemical processing of the base fuel on the efficiency of steam conversion have been described. Experimental study has been carried out in the range of water vapour/ethanol ratio 0.3... 2.7, pressure 0.175... 0.45 MPa, temperature 850... 950 K. By the method of experiment planning, the dependencies of indicated criteria for evaluating the energy efficiency on the process parameters have been obtained. It has been shown that the influence of the process pressure is essential. In the specified range of parameters for ethanol, the maximum value of the coefficient of increasing the calorific value of the base fuel reaches 0.21. Mechanical energy consumption when organizing the processes of thermochemical treatment is 6... 12% of the total energy costs and significantly affects the efficiency of utilization of secondary energy resources.

The work is devoted to analyzes the level of tax burden in Ukraine and EU countries. The role of the tax system of Ukraine in the context of economic reforms is considered. The level of tax burden in the EU member states is analyzed. The analysis of international ratings "Doing business" and "Paying Taxes", in particular the position of Ukraine in them is calculated in according to such indicators as: the overall level of tax burden, the number of tax payments and time to pay taxes. The level of tax burden in Ukraine is determined by the ratio of actual tax revenues to the consolidated state budget to the amount of gross domestic product. Based on the results of the analysis of the level of tax burden in Ukraine and the countries of the European Union, recommendations for optimizing the level of tax burden in Ukraine have been developed.

In this paper, the samples preparation, experimental details, and characterization of the Electrophoretic Deposition (EPD) of a thick film Barium Strontium Titanate (BST) capacitor intended for radio-frequency applications are reported. With a bias voltage from 0 V to 20 V, the Ba 0.7 Sr 0.3 TiO 3 capacitor fabricated demonstrates 49% of tunability. The quality factor and the microwave (MW) loss tangent are calculated from 500 MHz to 5 GHz. Using an one-tone measurement setup, the small signal S-parameters measurements for the BST thick film capacitor are also presented by applying input signals from -20 dBm to 4 dBm. The linearity and loss tangent are analyzed considering a comparison of two different bias voltages, 0 V and 10 V. For the first time, the BST thick films fabricated with EPD are implemented and measured in the MW regime.

The article is devoted to solving the problem of recognizing semiprecious minerals that are used in jewelry production. The intensive development of production leads to a reduction in the reserves of natural resources, including precious minerals. Therefore, the task of saving the use of minerals is urgent. In this article, to solve this problem, a new information method is proposed for recognizing and comparing the volumes of minerals in order to sort them. Improving the accuracy of sorting minerals is necessary to minimize the loss of valuable raw materials in the production of jewelry. According to the proposed technology, the total volume of the mineral that is supplied for sorting is determined, and then this gross volume is compared with one or several net volumes of jewelry produced. The proposed technical solutions allow increasing the accuracy of sorting minerals and reducing the amount of waste during further mechanical processing of semiprecious minerals. Ultimately, the proposed method helps to increase the economic efficiency of jewelry production and, as a result, contributes to the rational use of natural resources.

A theory of interaction of the electron with interface phonons at cryogenic temperatures in the cascade of broadband far infrared range quantum cascade detector was developed from first principles in the one-phonon approximation. The effect of all branches of interface phonons and different mechanisms of electron-phonon interaction on the spectral characteristics of the electron operating states in a cascade of the nanodevice is investigated.

To expand the area of parts made of non-compact alloys application, it is proposed to use one of the local surfaceplastic deformation methods- diamond slide burnishing (DSB). The peculiarities of local surface plastic deformation by DSB of parts made of heat-resistant alloy INCONEL 71S based on nickel obtained by selective laser sintering (SLS) have been investigated. The optimal modes of DSB parts have been determined based on the degree of their influence on the parameters of quality and microhardness of the surface layer. The regularities of changes in the studied parameters of roughness and microhardness have been established depending on various parameters of DSB. It has been found that to obtain the minimum roughness and maximum microhardness of the surface layer, the cumulative effect of burnishing parameters should be considered. The influence of DSB modes on the structure of the parts surface layer which is obtained by SLS has been shown. Based on the analysis of Pareto diagrams, the significance of the DSB parameters with respect to their effect on the roughness and microhardness of the surface layer of the samples obtained by SLS has been established. Using the Box Wilson steep ascent method, the optimal modes of parts DSB have been established. It has been found that the optimal modes of DSB are the burnishing force of 0.25 kN, the feed rate is 0.1 mm/rev, and the radius of the DSB sphere is 2.5 mm.

The results of using the Raman spectroscopy method for evaluating the condition of teeth with non inflammatory periodontal disease are presented in the work. Spectral features of the tissues of such teeth were found as a result of the experimental studies. It was shown that the main changes in the teeth are in the change of proline and hydroxyproline in cementum and root dentine of the tooth root.

The results of spectral analysis of gender differences in experiments with rats using the Raman spectroscopy method are presented in the work. The main spectral differences of the studied samples that depend on gender were found as a result of the studies.

This paper considers the mechanisms of the applying the subtasks prioritization on workflow performing by a distributed wireless computing system (DWCS) with a resources control mechanism based on the network-centric approach. The ordering by priority of subtasks allows to reveal the critical path and to speed up the execution of the subtasks. In this research, the setting of subtasks priority was performed according to the algorithm Heterogeneous Earliest-Finish-Time (HEFT). The experimental researches of the proposed approach are also presented in this paper.

The results of experimental study of periodontitis early diagnosis using optical methods (Raman spectroscopy and confocal microscopy) are presented. The features of Raman spectra of saliva for the studied groups of patients have been established. It is shown that the main markers of periodontitis are the lines of 1556 cm-1 and 1738 cm-1. The results of the research using Raman spectroscopy have been compared with the microscopic analysis.

The problem of the rational plastic’s waste utilization is reviewed. It is shown that it is one of the most effective method of the plastic’s waste processing into the artificial liquid fuel and its conversion into electrical power. The experience of previous researches and development, the analysis of constructive solutions and the results of experiments gave the reason to apply a technological solution with three reactors for the plastic waste processing. The economically efficient energetic complexes for wastes the plastic waste processing and electricity production is proved. The advantages of the proposed controlled thermo-catalytic plastic waste processing method are shown.

The perspectives of waste-heat recovery of low-speed diesel engines using metal-hydride units of continuous operation have been substantiated. The design scheme of a unit and parameters of operating environment have been described. The results of mathematical modeling of processes in a waste heat recovery metal-hydride unit have been represented. The work efficiency of a waste heat recovery metal-hydride unit as a part of a marine propulsion complex on the basis of a low-speed dual-fuel diesel engine has been revealed. The novelty of this study is the investigation of metal hydride technology for application in the gas fuel compressor drive of LNG-powered ships.

This study is devoted to the effect of minor admixtures of carbon nanotubes and Au-coated carbon nanotubes on the microstructure of solder/copper joints. The paste of solder Sn3.0Ag0.5Cu (known as SAC305) reinforced with 0.001, 0.003 and 0.005 wt.% of nanosized additions has been prepared as solder material. A microstructure of the solidified solder/copper joints was investigated by SEM. It was revealed that admixtures of the carbon nanotubes slow down the increase of the intermetallic layer Cu 6 Sn 5 , formed at the interface solder/copper. This effect was found in all studied uncoated and Au-coated carbon nanoparticles and could be connected with adsorption of nanoinclusions on the surface of grains in course of solidification. A comparison analysis revealed that the most favorable effect was obtained by adding of carbon nanotubes coated with Au to the SAC305 solder paste.