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The article presents results of the study of soybean and rapeseed vegetable oils’ qualitative composition dependence on the degree of raw materials grinding obtained by extraction in a stationary layer in a Soxhlet apparatus using methylene chloride as a solvent. A number of experiments were performed to determine the optical properties of oil by infrared spectroscopy. The absorption spectra for different oil samples are present in the article. The obtained results were compared with previous refractometric and UV-Vis spectroscopy studies.

Use of a noninvasive method for the diagnosis of diabetes by determining the concentration of acetone in the air during exhalation has been suggested in the research. Optical sensor based on a mixt...

The influence of the production conditions for rapeseed and soybean oils obtained by extraction in the system “solid – liquid” on the qualitative composition of the obtained vegetable oils has been studied. The main chemical values (acid value, iodine value, ester value, saponification value) and optical properties (refractometric refractive index and UV-Vis spectroscopy) for rapeseed and soybean oils obtained by extraction using methylene chloride as a solvent from different plant raw materials (grade of grinding is 0.2, 0.5 and 1.0 mm) and mixtures of crushed grain fractions have been determined. It has been shown that the grade of grinding of the raw material affects the quality of the obtained product.

Мета роботи. Виділення та ідентифікація продукту взаємодії верапамілу гідрохлориду з бромкрезоловим зеленим методами ІЧ-спектрофотометрії та 1H ЯMР спектроскопії. Матеріали і методи. У дослідженні використано робочий стандартний зразок верапамілу гідрохлориду, бромкрезоловий зелений (БКЗ), взірці готових лікарських форм вітчизняного та зарубіжного виробництва. Реагенти і розчинники: стандартний зразок верапамілу гідрохлориду, бромкрезоловий зелений, ацетон. Аналітичне обладнання: Спектрофотометр Bruker Alpha (Bruker Optik GmbH, Ettlingen, Germany) з використанням приставки (повного внутрішнього відбиття) ATR (пряме уведення речовини), спектрофотометр Specord 200 (Німеччина) (190–1100 нм). Результати й обговорення. Експериментально встановлено, що верапамілу гідрохлорид взаємодіє з бромкрезоловим зеленим у середовищі ацетону з утворенням йонного асоціату. ІЧ-спектр йонного асоціату відповідає сумі поглинань вихідних сполук із деякими відмінностями, що підтверджують його утворення. У йонному асоціаті в області 3600‒3400 см‒1 смуги фенольних –ОН проявляються з меншою інтенсивністю, що можна пояснити перетворенням БКЗ у хінонну структуру. У продукті також відсутні поглинання в області 2370см‒1 (R3N+Cl- у верапамілі гідрохлориді), що пояснюється утворенням йонного асоціату з БКЗ, а саме поглинання проявляється у вигляді уширеного сигналу в області 3200‒2000см‒1. Висновки. У результаті проведених досліджень встановлено, що верапамілу гідрохлорид взаємодіє з бромкрезоловим зеленим у співвідношенні 1:1, виділено та встановлено будову забарвленого продукту взаємодії верапамілу гідрохлориду з бромкрезоловим зеленим. За допомогою методів ІЧ- спектроскопії та спектрометрії ядерного магнітного резонансу підтверджено, що продуктом взаємодії є йонний асоціат.

Мета роботи: вивчити переваги та недоліки відеоасистованої паратиреоїдектомії. Матеріали і методи. У нашій клініці від лютого 2010 року до лютого 2019 року оперовано 103 пацієнти з приводу ПГПТ, з них було 84 жінки, середній вік хворих склав (58,2±12,1) року. Діагноз ПГПТ базувався на класичних симптомах, а саме наявності підвищених рівнів загального та/або йонізованого кальцію та інтактного паратгормону (ПТГ) у сироватці крові. Усіх пацієнтів розділено на дві групи: І група – 36 пацієнтів (35 %), яким виконано відеоасистовану паратиреоїдектомію, IІ група – 67 пацієнтів (65 %), яких оперували відкритим способом із двобічною експлорацією шиї. Результати досліджень та їх обговорення. У 35 % хворих виконано відеоасистовану паратиреоїдектомію, у яких за результатами топічних досліджень виявлено солітарну аденому ПЩЗ – ці пацієнти утворили І групу. У 59 (57 %) хворих ІІ групи виявлено супутню патологію щитоподібної залози, 4 пацієнти (4 %) в анамнезі мали операції на шиї в ділянці щитоподібної залози, ще у 4-х (4 %) – діагностовано рецидив або персистенцію ПГПТ. Обидві групи вірогідно не відрізнялися за віком та статтю, рівнями загального та йонізованого кальцію, ПТГ перед операційним втручанням. Тривалість операційного втручання була вірогідно меншою та довжина розтину коротшою у пацієнтів І групи. У двох (2 %) хворих ІІ групи та у жодного пацієнта І групи після операційного втручання розвинувся транзиторний парез поворотного гортанного нерва. Отримані результати дозволяють твердити, що відеоасистована паратиреоїдектомія у ретельно відібраних пацієнтів (35 %), за результатами ультрасонографії та сумнівних випадках сцинтиграфії із 99mТс-MIBI, є ефективним мініінвазійним методом операційного лікування хворих на ПГПТ, який дозволяє скоротити час хірургічного втручання та частоту післяопераційних ускладнень.

Object and purpose of research. This paper investigates brake resistor units of frequency-controlled propulsion drives in marine electric propulsion systems. This unit absorbs propulsion energy in case of generative braking. The purpose of this research is to develop a calculation procedure for the parameters of resistors in this unit. Materials and methods. The study is based on scientific and technical information available in the literature about electric drive theory, as well as on as well as on personal findings and experience of the authors gained in nu- merous R&D projects on marine electric propulsion systems. The method followed by the authors is based on the possibility to simulate various electromechanical devices and systems, including propulsion drives, in Simulink MATLAB software package. Main results. Development of engineering procedure that enables correct calculations and selection of electric equipment for brake resistor unit already at early stages of detailed design without the necessity of mockups for laboratory studies. Conclusion. Practical results obtained by the authors and applied in Simulink MATLAB software enable simulation of electromechanical processes taking into account non-linearity of their respective differential equations, which makes the procedure suggested by the authors accurate and handy.

Object and purpose of research. This paper studies electric drives of pod propulsion units installed at heavy-duty icebreakers of the new generations: their electric propulsion systems are based on synchronous motors and static frequency converters. The purpose of this work is to develop a flow chart and investigate electromechanical properties of vector-controlled synchronous propulsion drive that meets stringent requirements to the dynamics of electric propulsion systems aboard new-generation icebreakers. Materials and methods. The study is based on the data available in theoretical literature on electric drives, as well as on personal findings and experience of the authors gained in numerous R&D projects on marine electric propulsion systems. The method followed by the authors is based on the possibility to simulate various electromechanical devices and systems in Simulink application and Sim Power Systems library of MATLAB software package. Main results. The main result of this study is the flow chart of propulsion drive based on 6.5MW synchronous motor: this system is not only as fast and accurate in terms of output coordinates as the best examples of DC and frequency-controlled AC drives, but excels them in terms of power efficiency. Conclusion. Practical findings of the authors could be helpful in development of propulsion drives based on synchronous motors for electric propulsion system of advanced new-generation icebreakers.

Object and purpose of research. This paper discusses development of control system for synchronous reluctance motor with anisotropic magnetic conductive rotor. The purpose of the study is to obtain optimal control algorithms for this motor in terms of response time or power efficiency. Materials and methods. Optimal control algorithms for SynRMs with anisotropic magnetic conductive rotors are obtained through step-by-step correction with tuning to the technical optimum. This study suggests vector-based control algorithms to ensure robustness of SynRM with anisotropic magnetic conductive rotor. Main results. Control algorithms suggested in this paper for SynRM with anisotropic magnetic conductive rotor are robust, i.e. resistant to minor changes in motor parameters, so that dynamic behavior of the motor does not undergo any serious changes. This approach to control system was implemented in the tests of breadboard 500 kW SynRM with anisotropic magnetic conductive rotor. These test data confirmed operability and efficiency of this approach to design of the electric drive based on SynRM with anisotropic magnetic conductive rotor. Conclusion. These control algorithms enable optimal SynRM control in terms of response time or power efficiency, thus making the drives faster and more efficient, and are robust and resistant to minor changes in motor parameters.

Neuroinflammation is an integral part of epilepsy pathogenesis and other convulsive conditions, and non-steroidal anti-inflammatory drugs (NSAIDs) present a potent tool for the contemporary search and design of novel anticonvulsants. In the present paper, evaluation of the anticonvulsant activity of the potential NSAID dual COX-2/5-LOX inhibitor darbufelone methanesulfonate using an scPTZ model in mice in dose 100 mg/kg is reported. Darbufelone possesses anticonvulsant properties in the scPTZ model and presents interest for in-depth studies as a possible anticonvulsant multi-target agent with anti-inflammatory activity. The series of 4-thiazolidinone derivatives have been synthesized following the analogue-based drug design and hybrid-pharmacophore approach using a darbufelone matrix. The synthesized derivatives showed a significant protection level for animals in the scPTZ model and are promising compounds for the design of potential anticonvulsants with satisfactory drug-like parameters.

В роботі проведено дослідження електричних та фотоелектричних властивостей гетероструктури n-Zn0.5Cd0.5O/p-InSe. Плівка Zn0.5Cd0.5O наносилась на підкладку InSe методом магнетронного розпилення. Перевагою використання InSe є проста технологія виготовлення підкладки. Атомарно-гладка поверхня підкладки отримується простим механічним сколюванням завдяки особливостям хімічного зв'язку кристалів InSe. Вона не містить розірваних зв'язків та не потребує подальшого полірування. Якість вирощеної плівки Zn0.5Cd0.5O перевірялась за допомогою АСМ мікроскопії. На основі АСМ зображень проаналізовано структуру плівки Zn0.5Cd0.5O та процеси її росту. Для визначення механізму протікання струму в досліджуваній гетероструктурі були проведені виміри ВАХ при різних температурах. Обговорено хід прямих та обернених віток. Визначено значення діодного коефіцієнту. Проведені виміри ВФХ при кімнатній температурі. Визначена висота потенційного бар’єру на інтерфейсі. Досліджено спектри фотовідгуку гетероструктури. Встановлено нові закономірності, які не можна пояснити в рамках моделі домішкової фотопровідності. This paper studied the electrical and photovoltaic properties of n-Zn0.5Cd0.5O/p-InSe heterostructures. The n-Zn0.5Cd0.5O film was deposited onto InSe substrate by magnetron sputtering. The advantage of using InSe as the substrate is a simple technology. The atomically smooth surface of the substrate was obtained by simple mechanical exfoliation due to chemical bonding feature of InSe crystals. It did not contain broken bonds and did not require further polishing. The quality of the grown Zn0.5Cd0.5O film was controlled by AFM. The structure of the Zn0.5Cd0.5O film and its growth processes were analyzed on the basis of AFM data. The measurement of current-voltage characteristics at different temperatures was performed for the purpose of determining the mechanism of current flow in the studied heterostructures. The features of forward and reverse branches of current-voltage characteristics were discussed. The value of the diode coefficient was calculated. The capacity-voltage characteristics were measured at room temperature. The height of the potential barrier at the interface was calculated. The photoresponse spectra of heterostructures were studied. New regularities were found that cannot be explained within the framework of the impurity photoconductivity model.

Object and purpose of research. This paper studies automated frequency-controlled electric drive of a ship mechanism (thruster) in the electric propulsion system of various advanced ships. The purpose of this work is to develop a flow chart of frequency-controlled electric drive of ship mechanism (a thruster, as an example) that would feature, instead of currently used generator-based braking, the dynamic braking that offers significant gains in weight and size of the whole drive. Materials and methods. Scientific and technical information, as well as personal findings and experience of the authors, gathered over the years of various R&D projects in electric drives for various ship machinery. The solution to the challenge discussed in this paper is based on the method of developing a frequency-controlled electric drive, where static converter can convert the system of three-phase voltage with constant parameters into the one with smoothly-adjustable parameters, as well as to convert the said system into the system of constant, smoothly-adjustable voltage. Main results. The authors have developed a flow chart of frequency-controlled electric drive for ship mechanism (thruster) with dynamic braking, as well as enumerated other ship machinery items where electric drives are also practicable to feature this system. Their results are confirmed by simulations of electromechanical processes taking place in given electric drive of ship thruster. The diagrams of these processes, as well as their analysis, are also given in this paper. Conclusion. These solutions can be implemented in development of electric drives for machinery of advanced ships.

Досліджено протон-ініційоване перетво- рення дитіокарбаматних похідних 9,10-антрацендіону за умов кислотно-каталізованої циклодегідратації при дії суміші H2SO4-АсОН та подальшому обробленні перхлоратною кислотою. На основі даних спектральних методів (1Н, 13С ЯМР, ІЧ-, УФ-спектроскопії) встановлено, що реакція зупи- няється на стадії протонування атома Сульфуру тіокар- бонільної групи з утворенням перхлоратних солей. УФ спектри одержаних перхлоратів характеризуються гіпсохромним зсувом з чітко вираженим максимумом поглинання. Proton-initiated conversion of dithiocarbamate derivatives of the 9,10-anthracenedione under conditions of acid-catalyzed cyclodehydration using the action of a mixture of H2SO4-AcOH and further treatment with perchloric acid was investigated. Based on the data of the spectral methods (1H, 13C NMR, IR, UV spectroscopy), it is established that the reaction stops at the stage of protonation of the sulfur atom of the thiocarbonyl group with the formation of perchlorates. The UV spectra of the obtained perchlorates are characterized by a hypochromic shift with a clearly pronounced absorption maximum.

The results of phytosociological studies of pioneer lichen communities of siliceous outcrops carried out in 2014–2016 in Teteriv River basin (Ukraine) are provided. The dataset of 302 releves was analysed, 6 associations and 1 subassociation from 3 classes were distinguished as a result of the phytosociological survey in the Teteriv River basin. Four associations, i.e.: Aspicilietum contortae Kaiser ex Klement 1955, Cladonietum mitis Krieger 1937, Parmelietum conspersae Hilitzer 1925, Parmelietum somloensis Wirth 1995 and the alliance Aspicilion calcareae Albertson ex Roux 1978 are new for Ukraine, and one new association Aspicilio cinerei-Ramalinetum pollinariae Kapets et Khomyak, ass. nova is described here.

Мета роботи. Виділення та ідентифікація продукту взаємодії дилтіазему гідрохлориду з бромкрезоловим зеленим.Матеріали і методи. У дослідженні використано робочий стандартний зразок дилтіазему гідрохлориду, бромкрезоловий зелений (БКЗ), зразки готових лікарських форм вітчизняного та закордонного виробництва.Реагенти і розчинники: стандартний зразок дилтіазему гідрохлориду, бромкрезоловий зелений, ацетон.Аналітичне обладнання: спектрофотометр Bruker Alpha (Bruker Optik GmbH, Ettlingen, Germany) з використанням приставки (повного внутрішнього відбиття) ATR (пряме уведення речовини), спектрофотометр Specord 200 (Німеччина) (190–1100 нм).Результати й обговорення. Експериментально встановлено, що дилтіазем гідрохлорид взаємодіє з бромкрезоловим зеленим у середовищі ацетону з утворенням йонного асоціату. ІЧ-спектр йонного асоціату відповідає сумі поглинань вихідних сполук із деякими відмінностями, що підтверджують його утворення. У йонному асоціаті в області 3600–3400 см-1 смуги фенольних –ОН проявляються з меншою інтенсивністю, що можна пояснити перетворенням БКЗ у хінонну структуру. У продукті також відсутні поглинання в області 2370 см-1 (R3N+ Cl- в дилтіаземі гідрохлориді), що пояснюється утворенням йонного асоціату з БКЗ, а саме поглинання проявляється у вигляді уширеного сигналу в області 3200–2000 см-1.Висновки. У результаті проведених досліджень встановлено, що дилтіазем гідрохлорид взаємодіє з бромкрезоловим зеленим у співвідношенні 1:1, виділено та встановлено будову продукту взаємодії дилтіазему гідрохлорид із бромкрезоловим зеленим. За допомогою ІЧ-спектроскопії підтверджено, що продуктом реакції є йонний асоціат.

Object and purpose of research. The object of this study is electric propulsion drive of the electric propulsion system aboard Project 22220 multi-purpose nuclear icebreaker now under construction. The purpose of the study is to developcomputer-based model of electric propulsion drive for this icebreaker. The drive is frequency-regulated and has vector control algorithm. The model is intended to both analyse electromechanical processes taking place in the channels of the electric drive and to synthesize its control system. Materials and methods. The study was based on scientific & technical information available in literature on electric drive theory, as well as on personal findings of the authors and on their profound experience accumulated over many years of R&D in the sphere of marine electric propulsion systems. Solution to this problem is based on the possibility to simulate various electromechanical equipment and systems by means of Simulik application software and Sim Power Systems block library of MatLab package. Main results. The computer-based model developed under this work and representing electric propulsion drive of Project 22220 multi-purpose nuclear icebreaker makes it possible to investigate electromechanical processes taking place in different operational conditions of this drive. Virtual oscillograms were obtained for currents, voltages, RPM, power, electromagnetic moment, etc. These oscillograms characterize operation of the electric drive in the conditions of RPM regulation, power regulation, change of rotation direction, shaft cranking, ice milling, propeller jamming, decrease and increase of static load moment. The model can also be used to update the software governing microchip-based control system of the electric drive (this update becomes necessary during pre-commissioning set-to-work activities). Conclusion. The model of electric propulsion drive for Project 22220 icebreaker is an engineering tool that enables, already at early design stages, investigation and analysis of electromechanical processes: these data are necessary for proper selection of electric drive equipment. After corresponding update, this model can be used in detailed design of electric propulsion plants for ice-breaking ships of other designs.

Objective. To estimate the efficacy of the proposed combined videoendoscopic transcutaneous access in surgical treatment of the infected acute necrotic pancreatitis. Маterials and methods. Transcutaneous diapeutic punctures and draining were applied in 74 patients (control group), and in 23 (main group) for treatment of spread infected pathological foci, using combined videothoracoscoopic transcutaneous access. Results. Application of diapeutic interventions have permitted to defer the operative intervention performance up to 25 - 30-th day of the disease in all patients of the main group and in 82.7% – in a control one. In the main group a reduction of necessity in laparotomic necrsequestrectomy performance by 29.1%, of the invasive interventions – by 46.1%, and for mortality rate – by 2.9% was noted. Conclusion. Application of combined access have guaranteed the reduction of the invasive interventions performance rate, including laparotomic necrsequestrectomy.

Object and purpose of research. This paper studies automated frequency-controlled electric propulsion drive being an element of electric propulsion system aboard a multi-purpose nuclear icebreaker currently under construction. The purpose of this work is to develop a flow chart of electric drive control system based on vector control algorithm that meets a number of tough requirements to dynamic properties of electric propulsion drive. Materials and methods. Input data for this work were scientific and technical data given in the literature on electric drive theory, as well as personal findings and multi-year experience of the authors in the R&D activities related to electric propulsion of ships. Solution to this problem is based on designing a frequency-controlled electric propulsion drive as a closed-loop automatic regulation system with several control channels, each of these, in its turn, consisting of several circuits synthesized as per cascade compensation principles. Main results. The result of this work is a control system for frequency-regulated electric propulsion drive based on 20 MW squirrel-cage rotor that equals the best Russian and foreign electric drives in terms of response speed and accuracy of maintaining specified output coordinates. Conclusion. The value of the practical results obtained by the authors is development of the control system for electric propulsion drive as a totality of units performing mathematical operations with both controllable parameters and non-observable physical coordinates. This system is the basis for development of the software to be used in the microchip-based control system of electric propulsion plant for Project 22220 multi-purpose nuclear icebreaker currently under construction.

Distribution of species in earthworm communities under the influence of basic environmental factors was established using phytoindication methods. We described the environmental spectrum for lumbricid certain species. A. roseа and A. сaliginosа are identified as everytopic species, E. tetraedrais is rather everytopic than stenotopic. D. octaedra and De. rubidus are stenotopic.

The properties of transparent conductive materials based on wide-gap zinc oxide semiconductors are considered, which are promising in their application to photovoltaics and liquid crystal displays. The impact of aluminum doping on the conductivity of thin ZnO films is examined. Temperature studies of the concentration, mobility, and resistivity in the temperature range of 77–300 K are conducted, revealing the metal conductivity of highly doped films. The electroactivity of aluminum as a donor impurity in the ZnO lattice is studied for thin films grown using atomic layer deposition on glass and silicone, containing 1–7 at. % aluminum. The reasons behind the low electroactivity of Al in ZnO are discussed, as are the methods for its enhancement.

In order to solve the problems associated with the express registration of the presence of biologically active substances in callus biomass, we propose the use of cholesteric liquid crystal (CLC) with a spiral structure as a material of a sensitive element of optical sensor of flavonoids. Cholesteric liquid crystal BLO62 is proposed to use as a sensitive element. Spectral characteristics of alcohol solutions of flavonoids (20%, 40%, 70% and 90%) were obtained. The interaction of CLC with quercetin was analyzed. The scheme of the primary information signal converter is developed in which the current from the photodetector is transmitted to the developed signal converter. The device is implemented with the common use Atmega 328 microcontroller manufactured by Atmel. Speciality of this structural scheme is its flexibility and versatility, which makes it easy to reconfigure the parameters of the firmware for the registration of various types of investigated mediums.

We develop an electromagnetic-acoustic transducer which enables the determination of the elastic characteristics of materials and ultrasonic product testing with high reliability of detecting extremely dangerous cracks.

A sensitive, highly stable wide-band eddy current transducer for testing the thickness of protective dielectric coatings on metal articles is developed.

9,10-Anthraquinonylhydrazones containing nitrile, acyl, and ethoxycarbonyl groups reacted with hydrazine hydrate upon refluxing in dioxane or with sodium azide upon heating in DMF, giving the corresponding pyrazole and tetrazole derivatives.

The article is devoted to studying of influence of vacuum low-temperature annealing on the electrical and photoelectric characteristics of n-ZnO — p-InSe heterostructure. Indium monoselenide (InSe) is a semiconductor of the A3B6 group of layered compounds. The basic unit consists of two planes of metal atoms sandwiched between two planes of chalcogen atoms (Se—In—In—Se). The absence of dangling bonds on InSe cleaved surface makes it possible to use this semiconductor as a substrate for fabrication of heterostructures based on semiconductor materials with different symmetries and lattice spacings. Zinc oxide (ZnO) is the most suitable material for window materials and solar cells buffer layers application due to its marvelous transparency in the range of visible region. InSe single crystals were grown by the Bridgman technique from a nonstoichiometric melt and characterized by a pronounced layered structure along the whole length of a sample. ZnO thin oxide film was formed on freshly cleaved van der Waals surface of InSe layered crystal. n-ZnO — p-InSe heterostructure was prepared by the method of high-frequency magnetron sputtering. Sensitivity spectral areas were identified by MDR-3 monochromator with a resolution of 2.6 nm/mm. The current-voltage characteristics of the n-ZnO — p-InSe heterostructures showed a clearly pronounced diode character. In the forward bias of the initial samples, the diode factor had the value 3.7 at room temperature. It is shown that vacuum low-temperature annealing reduces shunt currents of the heterojunction, which is reflected in the decrease in the values of n from 3.7 to 2.7.

The stability and stabilization of the unstable spinning of a Lagrange top with an arbitrary axisymmetric cavity filled with an ideal fluid are addressed. The necessary stability conditions are used to demonstrate that it is possible to stabilize the top using rotating rigid bodies. Numerical calculations are in agreement with analytical results for a top with an ellipsoidal or a cylindrical cavity

The k.p method and the effective mass theory are applied to compute valence-band electronic structure and optical properties of ZnO1-xSx ternary alloys under biaxial strain. A significant modification of the band structure with increasing sulfur content is revealed. Features of wave-functions and matrix elements in the transverse electrical (TE) and transverse magnetic (TM) regimes for three valence subbands are studied and discussed. The results of calculations of interband transition energy and spontaneous emission spectra are in agreement with experimental data for ZnO1-xSx films grown by radio-frequency magnetron sputtering technique. (C) 2015 Elsevier B.V. All rights reserved.

Indium monochalcogenide (InSe) with a band gap of 1.25 eV is a promising material for photovoltaic applications. In this work, photosensitive anisotype n-ZnO/p-InSe heterojunctions were fabricated by means of radio-frequency magnetron sputtering of the zinc oxide onto freshly cleaved (0001) van der Waals surface of p-InSe single-crystal. Structural properties of the obtained heterostructures were investigated by means of X-ray diffraction. Surface morphology of the grown ZnO thin films was studied by means of atomic force microscopy. The electrical and photoelectrical properties of the heterojunctions were investigated using the current–voltage characteristics measured at different temperatures, capacitance–voltage characteristics and photoresponse spectra. The dominating current transport mechanisms through the heterojunctions under investigation were determined at forward and reverse biases. It was found that the developed heterojunctions n-ZnO/p-InSe show photosensitivity in the photon energy range (1.25–3.20 eV) at room temperature. In addition, we analyzed the influence of vacuum annealing of the heterojunctions at different temperatures on their photoelectric properties.

A study of the properties of materials based on the wide bandgap zinc oxide semiconductor, which are promising for application in optoelectronics, photovoltaics and nanoplasmonics. The structural and optical properties of solid solution Zn1−xCdxO films with different cadmium content, are studied. The samples are grown using magnetron sputtering on sapphire backing. Low-temperature photoluminescence spectra revealed emission peaks associated with radiative recombination processes in those areas of the film that have varying amounts of cadmium. X-ray phase analysis showed the presence of a cadmium oxide cubic phase in these films. Theoretical studies of the solid solution thermodynamic properties allowed for a qualitative interpretation of the observed experimental phenomena. It is established that the growth of the homogeneous solid solution film is possible only at high temperatures, whereas regions of inhomogeneous composition can be narrowed through elastic deformation, caused by the mismatch of the fil...

We have fabricated photosensitive anisotype n-CdxZn1−xO/p-CdTe heterojunctions by a deposition of Cd0.5Zn0.5O lm onto freshly-cleaved CdTe monocrystalline wafers using a radiofrequency magnetron reactive sputtering of a zinc cadmium alloy target. Fundamental electrical properties of the heterojunctions were studied. Dominant mechanisms of a current transport were found. n-CdxZn1−xO/p-CdTe heterojunctions were photosensitive and were able to operate both in photovoltaic and photodiode modes.

The technique of pulsed laser deposition and colloidal chemistry methods have been applied for synthesis of semimagnetic semiconductor Cd 1− x Mn x Te nanocrystals embedded in dielectric matrix. The performed analysis suggests a narrower size distribution for the colloidal nanoparticles. Optical absorption, Faraday rotation and photoluminescence spectroscopy have been used to characterize the grown quantum dot structures. The magneto-optical spectra of the Cd 1− x Mn x Te nanocrystals exhibit peculiarities typical for bulk semimagnetic semiconductors due to the strong spin-exchange interaction between band carriers and magnetic ions and simultaneously manifest some features because of confinement effects in low dimensional structures.

and Optical Properties of ZnO Films D.V. Myroniuka,∗, G.V. Lashkarev, I.I. Shtepliuk, V.Y. Lazorenko, V.T. Maslyuk, I.I. Timofeeva, A.S. Romaniuk, V.V. Strelchuk, O.F. Kolomys and V.V. Khomyak Frantsevich Institute for Problems of Material Science, NAS of Ukraine, 3 Krzhizhanivsky Str., 03680 Kyiv, Ukraine Institute of Electron Physics, NAS of Ukraine, 21 Universitetska Str., 88017 Uzhgorod, Ukraine Lashkaryov Institute of Semiconductor Physics, NAS of Ukraine, 41 pr. Nauki, 03028 Kyiv, Ukraine Fedkovich Chernivtsi National University, 2 Kotsubinsky Str., 58012 Chernivtsi, Ukraine

Photosensitive n-CdO/p-InSe heterojunctions were developed and studied for the rst time. The heterojunctions were fabricated by dc reactive magnetron sputtering of CdO thin lms onto the freshly cleaved p-InSe single-crystal substrates (0 0 1). Surface morphology of the obtained lms was studied by means of atomic force microscopy. From the X-ray di raction result it is shown that the CdO lm is polycrystalline with cubic structure. The mechanisms of current transport through the space-charge region under forward and back biases were established by investigation of temperature dependences of the I V characteristics. The main photoelectric parameters and the photosensitivity spectra were measured at room temperature.

Anisotype n-CdO-p-InSe heterojunctions are for the first time fabricated on the basis of layered InSe crystals. The temperature dependences of the current-voltage characteristics of the heterojunctions are studied and the mechanisms of charge transport across the barrier under forward and reverse biases are determined. The spectral range of photosensitivity of the heterojunctions is determined.

Investigation of Cd behavior in the ZnCdO alloys, where Cd content exceeds the solubility limit, is of importance due to possible impurity segregation and second phases’ formation in this material. We have studied the Cd behavior in the Zn 1− x Cd x O films deposited by dc magnetron sputtering on different substrates: c -plane Al 2 O 3 , bare Si (1 0 0) and Au (45 nm)/Si (1 0 0). It is revealed that Cd content of 10 at. % in the target results in average 6–8 at. % of Cd in the films, depending on the substrate type. Structural analysis based on X-ray diffraction revealed the absence of Cd-related secondary phases. Time-resolved photoluminescence (TRPL) and high-resolution energy dispersive X-ray analysis (EDX) help to understand the recombination dynamics of spontaneous emission and to establish correlations between cadmium content and radiative lifetime. We have revealed that the internal quantum efficiency is influenced by the Cd content and defect concentration. It is suggested that increasing of the cadmium content results in the reduction of nonradiative recombination centers originating from point defects.

We report the low-temperature (250 °C) fabrication of n-ZnCdO/p-SiC heterostructures by direct current magnetron sputtering (DC MS) technique. As-grown heterostructures exhibit diode characteristics: current–voltage measurements showed a typical rectifying characteristic of a p–n junction and the presence of series resistance. It is found that the turn-on voltage of heterostructures depends on the acceptor concentration in p-SiC. Via Cd doping of ZnO the energy barrier for holes can be lowered, which promotes the hole injection from the p-type layer to the n-type layer as well as favors the radiative recombination in the n-ZnCdO layer.

ZnO thin films have been grown on the sapphire ( с -Al 2 O 3 ) substrates at the temperature of 250 °C by means of the direct current (DC) magnetron sputtering technique. The crystal structure and surface morphology of the deposited films were investigated by X-ray diffraction (XRD) and atomic force microscopy (AFM). The optical transmission, reflection and luminescence spectra at 300 K were analyzed for both the as-grown and post-annealed ZnO films. Using the λ -modulation method gives the possibility to reveal the main features of the energy band structure and the nature of the radiative transitions causing the ultraviolet (UV) luminescence.

Possibilities of various diagnostic methods for biliary hypertension detection in chronic pancreatitis were analyzed. Biliary hypertension was revealed in 163 (31%) patients, suffering chronic pancreatitis. The laboratory investigations data, ultrasonographic investigation, computer tomography, endoscopic retrograde cholangiopancreatography, magnet-resonance cholangiopancreatography, intraoperative measurement of the biliary ducts width, intraoperative measurement of biliary pressure were applied for diagnosis. Endoscopic retrograde cholangiopancreatography, magnet-resonance cholangiopancreatography and intraoperative measurement of biliary pressure are considered the most sensitive methods for chronic pancreatitis diagnosis.

In experiment the impact of intraabdominal hypertension (IAH) on an acute pancreatitis (AP) course was studied up. The procedure of an acute experiment, using intraparenchymatose introduction of 40% solution of ethanol, was proposed. The isolated influence of IAH on target organs was investigated, as well as its impact on the simulated severe AP course. Morphological changes in pancreas, small intestine, kidneys, liver in an AP were studied up. While performing the investigation a negative impact of IAH in AP was noted, such as the polyorgan insufficiency occurence.

Anisotype surface-barrier n-Cd0.5Zn0.5O/p-CdTe heterojunctions are fabricated by the high-frequency sputtering of a Cd0.5Zn0.5O alloy film onto a freshly cleaved single-crystal CdTe surface. The main electrical properties of the heterojunctions are studied and the dominant mechanisms of charge transport are established, namely, the multistage tunnel-recombination mechanism under forward bias, Frenkel-Pool emission, and tunneling under forward bias. The influence of the surface electrically active states at the heterojunction interface is analyzed and their surface concentration is evaluated: Nss ∼ 1014 cm−2.

The Zn0.9Cd0.1O films have been prepared using the direct current (dc) reactive magnetron sputtering technique under the different ratios of Ar/O2. We have studied the effects of the different gas concentrations (Ar/O2) and the deposition powers on a crystal structure, a surface morphology, and optical properties of the Zn0.9Cd0.1O films. The surface and the structure investigations have shown a strong influence of the growth conditions on the film microstructure. The structural analysis revealed that all grown films are polycrystalline and single-phase. It was found that increasing the argon concentration leads to an improvement of the structural quality of the Zn0.9Cd0.1O films. The features of controlling the band gap and the surface morphology of the Zn0.9Cd0.1O ternary alloys by changing the growth parameters have been discussed.

We studied structural and optical properties of 5′ replaced pyrazoline by hindered phenol 2,6-di-tert.-butyl-4-(2,5-diphenyl-3,4-dihydro-2H-pyrazol-3-yl)-phenol (HPhP) films for application in organic light-emitting diode (OLED) as a hole transport layer (HTL). Analysis of impedance and current–voltage characteristics of ITO/HPhP/Al structure has shown that the current is limited by a space charged region with exponential distribution of traps near Fermi level. Characteristics of electroluminescence structure ITO/HPhP/Alq3/poly(ethylene glycol) dimethyl ether/Al was studied and analyzed. We performed the comparative analysis of luminescence time decay in two types of electroluminescent devices with HTL from pyrazolines derivative with hindered phenol and without it. We showed that hindered phenol in HTL slows down the degradation processes in OLED.

Various approaches have been tested for improving the production of usable microtubers in tissue culture propagation of virus-free potato material. Cultures in which microtubers are spontaneously produced under conditions when only vegetative growth should occur are generally not usable, either for further propagation or for microtuber production. Feeding with supplementary sucrose solution has been shown to stimulate such cultures to produce adequate quantities of usable microtubers. Use of a liquid medium instead of a solid medium was another method used to increase microtuber yield. An attempt was also made to increase efficiency by placing more transplants in each culture flask. Improvements were obtained by making various adjustments in the density of plants and the volume of medium, with supplementary feeding if necessary. The density could best be expressed in relation to total surface area of growth chamber used.