bluuebunny/crossref_metadata_2025 huggingface dataset:
Usage virtual devices for measuring voltage in course of theoretical fundamentals of electrical engineering
Authors: Shirokova Z. G. , Melnikov D. V. , Petrovichev M. A.
Published: November 2019

The combined methods of training using the multimedia laboratory in the framework of the implementation of modern approaches to the learning process, in practice are article shown. It’s impossible to provide the high quality of the educational process without modern laboratory facilities. Unitrain I laboratory developed by the Lucas Nulle allows to combine theory and practice, creating a highly effective and efficient learning environment using computer technology. A set of virtual devices for measuring voltages in an electrical circuit is considered, which is necessary to perform laboratory and practical work for the development of the course of theoretical foundations of electrical engineering. The comparison with real devices measurements is performed. Conclusions are given.
Synthesis of movement control mechanism for vertical guidance of supporting-rotary device measuring antenna complex of desired dynamics
Authors: Aksenov A. V.
Published: November 2019

The parametric identification of the mechanism of vertical guidance of the support-rotary device of the measuring antenna complex is carried out. The transfer function is defined, which is presented as a model of the control object. The results of experimental studies allow to determine the average speed of movement of the pivoting device on the corner of the place with the required supply voltage. An integrator and a transfer function of the controller are introduced into the algorithm of the control scheme of the object position. The developed scheme of the control system allows to provide the dynamics corresponding to this speed. The block diagram of the control system implementing the necessary dynamics of the object is given. The control algorithm with the controller is studied using the Matlab 7.9.0 software package. The article presents the logarithmic frequency characteristics of open and closed systems. According to the results of the proposed method of synthesis of the controller for the device, the time of the transient process of the installation is determined; a smooth stop of the device is provided, oscillations are eliminated.
Ways to improve efficiency of measuring parameters of antenna devices
Authors: Mazin A. V. , Nikolaev P. V.
Published: November 2019

The paper considers the measurement methods implemented in compact polygons. The main advantage of antenna measurements in compact polygons is their conduct indoors-anechoic chamber. The authors analyze the information about the measuring system of the antenna device. The most effective components of measurement of parameters of antenna devices, which can be implemented in the measuring system and show high results in antenna measurements, are determined. The proposed method is investigated applicable to the minimization of the basic errors occurring in the measuring system of the antenna device, the analysis of its effectiveness for the studied errors. A generalized method of analysis of information about the measuring system is proposed, experimental studies of this method are presented. The application of the proposed method allows to increase the accuracy of measurement of antenna devices.
Фотоэмиссионные исследования электронной структуры GaN, выращенного методом молекулярно-пучковой эпитаксии с плазменной активацией азота
Authors: Тимошнев С.Н. , Мизеров А.М. , Бенеманская Г.В. , Кукушкин С.А. , Буравлев А.Д.
Published: November 2019

The results of experimental studies of the electronic and photoemission properties of an epitaxial GaN layer grown on a SiC/Si(111) substrate by plasma assisted molecular beam epitaxy are presented. The electronic structure of the GaN surface and ultrathin Li/GaN interface was first studied in situ under ultrahigh vacuum conditions under different Li coverages. The experiments were performed using photoelectron spectroscopy with synchrotron radiation in the photon energy range of 75–850 eV. The photoemission spectra in the region of the valence band and surface states and the photoemission spectra from the N 1s, Ga 3d, Li 2s core levels were studied for different submonolayer Li coverages. It is established that Li adsorption causes significant changes in the general form of the spectra induced by charge transfer between the Li layer and the lower N and Ga layers. It is established that the GaN surface has predominantly N-polarity. The semiconductor character of the Li / GaN interface is shown.
Зависимость свойств вариативных градиентно-пористых структур кремния от метода формирования
Authors: Рубцова К.И. , Силина М.Д.
Published: November 2019

A series of samples of gradient-porous silicon structures with crystallographic orientations (100) and (111) by deep anode etching was obtained. Dependences of the rate of deep anodic etching and the depth of the porous layer of the samples on the anode current density are shown. The absorption and reflection coefficients of the samples were investigated by optical spectrometry depending on their crystallographic orientation and the depth of the porous layer. The influence of water solutions on the optical properties of the samples was determined.
Дислокационные реакции в полуполярном слое GaN, выращенном на вицинальной подложке Si(001) с использованием буферных слоев AlN и 3C-SiC
Authors: Сорокин Л.М. , Гуткин M.Ю. , Mясоедов A.В. , Kaлмыков A.E. , Бессолов В.Н. , Кукушкин С.А.
Published: November 2019

The interaction between a+c-type and a-type dislocations in thick (up to 14 µm) semipolar GaN layer grown by hydride vapor phase epitaxy on a 3C SiC/Si(001) template has been detailed investigated by means of transmission electron microscopy. It is shown, that the expansion of a dislocation half loop with Burgers vector b=1/3<1-210> during cooling process can be blocked by its reaction with a threading dislocation with b=1/3<1-210> to form a dislocation segment with b=<0001>. This dislocation reaction is discussed in terms of the energy relaxation. The approximation estimate made within the linear tension approach gives the total energy gain ~7.6 eV/Å (that is, in general, ~45.6 keV for the observed screw dislocation segment of length 600 nm formed as a result of the reaction). Using the core energy calculations, the dislocation core contribution was also estimated as ~19.1 keV.
Формирование нанокристаллов GaN на поверхности графеноподобных g-AlN и g-Si-=SUB=-3-=/SUB=-N-=SUB=-3-=/SUB=-
Authors: Милахин Д.С. , Малин Т.В. , Мансуров В.Г. , Галицын Ю.Г. , Кожухов А.С. , Александров И.А. , Ржеуцкий Н.В. , Лебедок Е.В. , Разумец Е.А. , Журавлев К.С.
Published: November 2019

In this work, the GaN nanocrystals formation on a graphene-like modification of AlN (g-AlN) and graphene-like silicon nitride (g-Si3N3) by ammonia molecular beam epitaxy was studied. The GaN growth on the g-Si3N3 surface was found to result in the misoriented nanocrystals formation. With the GaN growth on the g-AlN surface, epitaxial growth of the equally oriented GaN quantum dots with graphite-like modification was observed. The lattice parameters and the energy structure of two GaN graphite-like modifications with alternating layers AB (graphite structure) and AA’ (hexagonal boron nitride structure) were calculated.
This work was supported by the Russian Foundation for Basic Research (№ 17-02-00947-Бел_а and 18-52-00008-а). This work was supported by the Belarusian Republican Foundation for Basic Research in the framework of the joint project Ф18Р-234.
Исследования термоэлектрических свойств сверхрешеток на основе силицида марганца и германия
Authors: Дорохин М.В. , Кузнецов Ю.М. , Лесников В.П. , Здоровейщев А.В. , Дёмина П.Б. , Ерофеева И.В.
Published: November 2019

Abstract In this paper, we present the results of the study of thermoelectric materials formed by pulsed laser deposition on sapphire substrates and representing thin MnSi_1.74 films with intermediate germanium layers. A sharp decrease in the thermal conductivity coefficient of superlattices based on manganese silicides and germanium in comparison with single layers of manganese silicide with an equivalent thickness is shown. This allows significantly increasing the thermoelectric figure of merit. The obtained values of the coefficient of thermoelectric figure of merit are comparable with the known literature values that are typical for similar structures.
Глицин-нитратный синтез твердых растворов метатитаната бария-стронция
Authors: Белышева Д.Н. , Синельщикова О.Ю. , Тюрнина Н.Г. , Тюрнина З.Г. , Свиридов С.И. , Тумаркин А.В. , Злыгостов М.В. , Уголков В.Л.
Published: November 2019

The effect of the compound of glycine-nitrate compositions on the completeness of the formation of solid solutions of barium-strontium metatitanate was studied. It was shown that the decomposition of all examined glycine-nitrate compositions begins at a temperature of 180 ° C, but depending on the glycine content and the pH, it has a different character. The optimal condition for the formation of single-phase products is the volumetric combustion mode, achieved when the content of the reducing agent is higher than the oxidizing agent in the composition. Such compositions make it possible to obtain nanosized powders of Ba1-xSrxTiO3 solid solutions (0≤ x≤0.4) by calcination at a temperature of 550 ° C, as well as to introduce them into composites based on porous magnetic glass, avoiding the interaction between the formed ferroelectric phase and the glass matrix.
Протонпроводящие композиционные материалы на основе соединения Cs-=SUB=-6-=/SUB=-H(HSO-=SUB=-4-=/SUB=-)-=SUB=-3-=/SUB=-(H-=SUB=-2-=/SUB=-PO-=SUB=-4-=/SUB=-)-=SUB=-4-=/SUB=-
Authors: Коморников В.А. , Гребенев В.В. , Тимаков И.С. , Зайнуллин О.Б.
Published: November 2019

Composite proton-conducting materials xCs6H (HSO4) 3 (H2PO4) 4+ (1 - x) AlPO4 were obtained in the composition range (x = 0.9–0.7). The methods of x-ray phase analysis, impedance spectroscopy, electron scanning microscopy studied their physicochemical and transport properties.
Низкотемпературный синтез нанокристаллов alpha-SiC
Authors: Нусупов К.Х. , Бейсенханов Н.Б. , Бакранова Д.И. , Кейнбай С. , Турахун А.А. , Султан А.А.
Published: November 2019

Abstract Thick SiC_ x films have been deposited on a c -Si surface by radiofrequency (rf) magnetron sputtering (150 W, 13.56 MHz, Ar flow 2.4 L/h, 0.4 Pa) of graphite and silicon targets. The X-ray diffraction study shows that fast annealing of the SiC_ x film deposited on the c -Si surface for 3 h leads to the low-temperature (970°C) formation of hexagonal structural phases α-SiC (6 H -SiC and other) along with the cubic modification of silicon carbide β-SiC. The IR spectroscopy has shown the formation of SiC nanocrystal nuclei due to the energy action of the rf plasma ions on the upper layer of the SiC film during its growth. The data of X-ray reflectometry demonstrate a high density of the films up to 3.59 g/cm^2 as a result of formation of dense C and SiC clusters in the layers under action of the rf plasma.
Магнитные свойства нанокристаллов Bi-=SUB=-1-x-=/SUB=-Ca-=SUB=-x-=/SUB=-FeO-=SUB=-3-delta-=/SUB=-
Authors: Ломанова Н.А. , Томкович М.В. , Осипов А.В. , Панчук В.В. , Семенов В.Г. , Плешаков И.В. , Волков М.П. , Гусаров В.В.
Published: November 2019

Nanocrystalline magnetically ordered materials based on Ca-doped bismuth orthoferrite were synthesized by glycine-nitrate combustion method. The samples were characterized by X-ray diffractometry, helium pycnometry, Brunauer–Emmett–Teller method, scanning electron microscopy and elemental energy dispersive microanalysis. It was shown that all samples were isostructural to bismuth orthoferrite. The particles of nanopowders (with average particle size of about 0.3 m) were composed of nanocrystals (with average crystallite size of about 40 nm). The difference between magnetic properties of Ca-doped samples and pure bismuth orthoferrite were demonstrated by Mössbauer spectroscopy and magnetometry. It was found that the samples contain nanocrystals with modified magnetic parameters and a small amount of fine fraction of other phases with a magnetic order.
Флексокалорический эффект в тонких пластинах титаната бария и титаната стронция
Authors: Старков А.С. , Старков И.А.
Published: November 2019

The flexoelectric effect in a thin plate of a ferroelectric with cubic symmetry is investigated on the basis of the Love-Kirchhoff model. The electric and elastic fields in a ferroelectric are described within the framework of the Landau-Ginzburg thermodynamic potential. The influence of the inhomogeneity of the polarization distribution in the plate is taken into account. Found values for plate bending caused by electric field application make it possible to calculate the dependence of the entropy change on temperature in the barium and strontium titanate plates (flexocaloric effect).
Синтез квазикристаллических порошков и покрытий методом вакуумного плазменно-дугового испарения
Authors: Ушаков А.В. , Карпов И.В. , Федоров Л.Ю. , Шайхадинов А.А. , Дёмин В.Г. , Демченко А.И. , Гончарова Е.А. , Зеер Г.М.
Published: November 2019

Quasicrystalline coatings of the Al-Cu-Fe system were obtained by sputtering the cathode using a pulsed high-current low-pressure arc discharge followed by deposition on a hot (600 ° C) and cooled substrate (25 ° C). The surface morphology, chemical and phase composition of evaporation products in the form of powder and the resulting coatings were studied. Powders and coatings were also annealed and the phase composition variation was studied. It was found that during the evaporation process a significant change in the chemical composition occurs in the form of loss of Al from the surface of the particles and the coating, which leads to a decrease in the content of the ψ phase. However, subsequent annealing and sputtering on a hot substrate lead to an increase in the ψ phase, as well as the density and hardness of the coatings.
Влияние температуры термомеханической обработки на гетерогенную структуру углеродного волокна
Authors: Тюменцев В.А. , Фазлитдинова А.Г. , Подкопаев С.А.
Published: November 2019

The change in the fine structure of carbon fibers with increasing temperature of thermomechanical treatment was studied by X-ray diffraction analysis. It is shown that the fiber material is heterogeneous, its component composition is determined by the modes of thermomechanical treatment, and also depends on the angle of the orientation of the coherent scattering regions relative to the fiber axis
Спонтанные переходы в состояние высокой проводимости в композитных пленках поливинилхлорида
Authors: Власова Т.В. , Расмагин С.И.
Published: November 2019

The results of experimental studies of conductivity anomalies in film samples of specially synthesized copolymer are analyzed, in which in PVC macromolecules the polyacetylene molecular fragments are embedded with a variable concentration. It has been experimentally established that spontaneous and stimulated conduction jumps occur in such samples by 13 orders of magnitude, and the life of each of these states can be very large from a few minutes to a day. In paper we propose a qualitative model describing the anomalous behavior of the conductivity of the PVC composite, comprising the mechanisms of stabilization of high conductivity state, the conditions of development of instability in the transitions between the states, as well as the reasons for long living state of high conductivity even when the applied voltage is switched off. Simple numerical estimates confirming the reality of the proposed mechanisms are also considered.
Применение формулы Донкина в теории отражающих и поворотных устройств
Authors: Голиков Ю.К. , Бердников А.С. , Антонов А.С. , Краснова Н.К. , Соловьёв К.В.
Published: November 2019

Abstract Electrostatic turning devices are electron- and ion-optical elements changing the direction of movement of a parallel monochromatic beam of charged particles by a given angle without affecting a beam’s parallelism. The trajectory similarity principle for electric fields homogeneous in Euler terms ensures the fulfillment of this property for the fields with a homogeneity of a zero power. The Donkin formula for 3D homogeneous harmonic functions produces extremely wide class of analytic expressions describing homogeneous electric potentials of a zero power. This paper considers the algorithm of synthesis of electrostatic turning devices that transform input parallel monochromatic beams into output parallel monochromatic beams. The algorithm is based on the Donkin formula and ensures beam stability for small deviations from the electric field’s symmetry plane.
Влияние электронного строения примеси на физические свойства, дефектную структуру и особенности технологии легирования кристаллов ниобата лития
Authors: Макарова О.В. , Палатников М.Н. , Бирюкова И.В. , Сидоров Н.В.
Published: November 2019

Macro- and microstructure were researched for doped LiNbO3 crystals. The transmission spectra and the effective distribution coefficients of the dopant were studied. The analysis of literature data on ternary phase diagrams of systems Li2O-Nb2O5-dopant oxide and electronic configurations of dopants has revealed a possibility to predict technological growth conditions and quality of doped lithium niobate crystals. At this p-elements (boron) provide growth of structurally and compositionally uniform LiNbO3 crystals without incorporation of a dopant into the structure. Metals, s- and d-elements (magnesium and zinc) influence the melts and the crystal properties similar. At this non-periodical domain structures and similar types of point defects appear. Metals of f-elements (cerium) order the melt structure in such a way that provide forming of growth regular domain structure in LiNbO3 crystals due to their electron configurations.
Keywords: crystal, lithium niobate, doping, optical microscopy.
Экстракция ионов из полярного раствора с использованием поверхностно-модифицированного мембранного интерфейса
Authors: Балакин, А.А. , Хидиров С.Г.
Published: November 2019

The possibility of field extraction of ions from a polar solution was demonstrated using a polymer track membrane with a conductive coating as an interface. The time-of-flight spectrum of ions extracted from a KI solution in a water-glycerin mixture by a nanosecond electric field pulse was obtained. The use of a conductive coating made it possible to significantly lower the voltage of the extracting pulse and reduce the influence of secondary processes on the composition of ions generated in a pulsed membrane ion source.
Строение и колебательные спектры димерного комплексного фторида галлия (III) с катионом тетраметиламмония
Authors: Войт Е.И. , Давидович Р.Л. , Удовенко А.А. , Логвинова В.Б.
Published: November 2019

Определена кристаллическая структура димерного комплексного фторида галлия(III) [N(CH_3)_4]2[Ga2F8(H2O)2], составленная из тетраэдрических катионов [N(CH_3)_4]+ и димерных комплексных анионов [Ga2F8(H2O)_2]2-, образованных объединением двух слегка искаженных октаэдрических групп GaF5(H2O) общим ребром F-F. Водородными связями O-H·sF димерные комплексные анионы [Ga2F8(H2O)_2]2- объединяются в полимерные цепи, между которыми расположены катионы тетраметиламмония. На основании квантово-химических расчетов выполнено отнесение полос в колебательных спектрах синтезированного соединения. В спектрах идентифицированы полосы, относящиеся к участвующим в водородных связях колебаниям молекул H2O, аниона и катиона. Ключевые слова: галлий(III), комплексный фторид, кристаллическая структура, тетраметиламмоний, димер, колебательная спектроскопия.
Барические изменения параметров оптической индикатрисы кристаллов литий натрий сульфата
Authors: Стадник В.И. , Щепанский П.А. , Брезвин Р.С. , Рудиш М.Я. , Матвиив Р.Б.
Published: November 2019

The spectral, temperature, and pressure dependences of the birefringence Δni of LiNaSO4 crystals are studied. Dispersion Δn(λ) is found to be anomalous. The uniaxial compression leads to different in magnitude and sign changes of Δnі. The dispersion effect of Δnі changes is weakening under the influence of pressure sigma ⟘ z and increases in the case of sigma || z. The baric changes of the refractive indices are estimated. The refractive indices of the LNS crystal are found to increase under the action of uniaxial pressure, which may be due to the compression of the crystal and a change in the nature of its interatomic bonds.
Отражение света от слоя гиперболического метаматериала
Authors: Петров Н.С. , Курилкина С.Н. , Зимин А.Б. , Белый В.Н.
Published: November 2019

In this paper, we study the features of reflection of a plane elliptically polarized electromagnetic wave falling from an isotropic non-absorbing medium on a layer of hyperbolic metamaterial (HMM) the optical axis of which is parallel to the interface and the diagonal values ​​of the dielectric constant are less than the dielectric constant of an isotropic medium. It is shown that changing the values of the angle of incidence and the angle between the plane of incidence and the optical axis of the HMM one can realize different regimes of refrection: when ordinary ( or extraodinary) wave or both waves decay from the interface. Meanwhile, in the latter case, for some values ​​of the angles the decaying can be nonexponential. For these three cases, numerical calculations of the reflection coefficient from the ITO / Ag nanostructure layer are performed. When the polarization of the incident wave varies, the energetic reflection coefficient changes from minimum to maximum values which depend on the layer thickness. Unlike usual anisotropic media, in all cases the maximum value of the reflection coefficient tends to unity with increasing the layer thickness. When the amplitude of the ordinary or extraordinary wave does not decrease from the interface, the minimum reflection coefficient periodically vanishes with increasing layer thickness due to the interference. In the case when both waves decay, and under some conditions the incidence is not exponential, the minimum reflection coefficient vanishes at a certain layer thickness, and then tends to unity.
Транспортировка предельно коротких импульсов излучения в волноводах с неодносвязным поперечным сечением
Authors: Розанов Н.Н.
Published: November 2019

The analysis of the features of transportation of few cycle radiation pulses in metal waveguides is carried out. It is concluded that mode dispersion can be suppressed and thereby the shape of pulses, including subcycle and unipolar pulses is preserved, at distances limited by absorption in metals.
Излучение резонансной среды, возбуждаемое лазерным излучением с периодической фазовой модуляцией в режиме сильной связи поля и вещества
Authors: Архипов Р.М. , Архипов М.В. , Егоров В.С. , Чехонин И.А. , Чехонин М.А. , Багаев С.Н.
Published: November 2019

In this paper, the radiation of a two-level resonant medium placed in a cavity and excited by a laser pulse with periodic phase modulation is studied theoretically. The analysis is carried out on the basis of an analytical and numerical solution of the system of Maxwell-Bloch equations under conditions when the regime of strong coupling of the field and matter is realized. Under these conditions, this system is similar to a polariton laser. A high excitation efficiency of a polariton laser by a phase-modulated radiation pulse compared with a pulse without phase modulation of the carrier frequency is shown. It is shown that the main reason for the effective excitation of polariton modes of the medium is the occurrence of a difference combination parametric resonance. The results obtained open up new possibilities in the excitation of radiation from polariton lasers by low-power pumping laser radiation with frequency modulation.
Квантовое сжатие поля одноатомного лазера в условиях переменной константы связи
Authors: Бобрикова В.А. , Хачатрян Р.А. , Баранцев К.А. , Попов Е.Н.
Published: November 2019

In this work we investigate unsteady regime of generation of squeezed light in a single-atom laser. Dependences of the parameter of quantum squeezing and light intensity on modulation frequency of the coupling constant between an atom and field were calculated numerically for this. We showed that at the modulation frequency equal to double coupling constant parametric resonance occurs. This regime leads to more effective quantum squeezing than regime under steady generation with the same parameters of the pumping and the relaxation.
Оптические и фотолюминесцентные свойства тонкопленочной структуры ZnO-ЦТСЛ в ультрафиолетовом и видимом диапазонах спектра
Authors: Григорьев Л.В. , Егорова Я.Б. , Быков Н.А. , Семенов А.А. , Никитин А.А.
Published: November 2019

The results of a study of the structural, optical, and photoluminescent properties of the thin-film structure ZnO/ferroelectric ceramics PLZT are presented. The results of X-ray diffraction analysis of a zinc oxide film synthesized on a PLZT substrate and on a quartz substrate are presented. The transmission spectra, reflection spectra, absorption spectra, and spectral dependence of the photoluminescence of the thin-film structure of ZnO- PLZT and the structure of ZnO-SiO2 in the ultraviolet and visible spectral ranges are presented.
Влияние термической обработки и солнечной радиации на оптические характеристики наноструктур оксида цинка
Authors: Уролов Ш.З. , Жалолов Р.Р. , Шаймарданов З.Ш. , Маматкосимов М.А. , Абдурахманов А. , Курбанов С.С.
Published: November 2019

Emission properties of ZnO nanorods and nanocrystals after high-temperature annealing in air and irradiation with high-intensity solar radiation have been studied. As-synthesized nanorods and nanocrystals under UV radiation exhibit a luminescence with maxima at around 380-384 and 560-570 nm. In both nanostructures, after heat treatment and irradiation with high-intensity solar radiation, an increase in the intensities of the short-wavelength luminescence bands is observed. In addition, after heat treatment and irradiation, in nanorods the long-wavelength luminescence band vanishes, while a new band at 520 nm appears in the luminescence spectrum of the nanocrystals. Irradiation with solar radiation has a greater effect on the emission properties of nanorods than nanocrystals and it is possible, caused by predominantly radiation heating (annealing) of nanorods than nanocrystals.
Возможности применения геометрической оптики для расчетов нано- и микроструктур в фотовольтаике
Authors: Класс Е.В.
Published: November 2019

Numerical simulation of nano and microstructured photovoltaic materials be means radiation transport software may become quite resource-intensive due to poor convergence of the applied optical -properties estimation method. In this paper, applicability of the geometrical optics approximation to microstructure-property modeling was illustrated by mutual comparison of the results of Monte-Carlo simulation in 3D POKS-RG program with a number of available experimental data about optical properties of nano- and microstructures.Numerical simulation accounting peculiar roughness of the surfase as a side effect of etching in microfabrication were in acceptable agreement with the experimental results. The furher analysis revealed essential influence of substrate surfase roughness onto the absorption of the incident light. The aforementioned peculiarity results in nonuniform structure-height distribution of change carriers and might partially cause the modest efficiency of radial p-n junction solar gells.
Переходные зоны в планарных W-световодах
Authors: Отрохов С.Ю.
Published: November 2019

На основе численного решения дисперсионного уравнения исследованы переходные зоны на границах одномодового и двухмодового режимов для некоторых конфигураций планарных W-световодов. Показано, что размеры рассмотренных переходных зон на частотах отсечки основной, первой нечетной и второй четной мод существенно зависят от геометрических и оптических параметров W-световодов. Указанные обстоятельства важно учитывать при подборе параметров W-световодов с тем, чтобы обеспечить в них устойчивый одномодовый или многомодовый режим, необходимую концентрацию поля и эффективную фильтрацию вытекающих мод. Ключевые слова: плоский пятислойный W-световод, дисперсионное уравнение, частота отсечки, переходная зона, коэффициент преломления промежуточного слоя, внешнее поперечное волновое число, вытекающие моды.
Сравнительный анализ чувствительности оптических датчиков на поверхностных волнах, возбуждаемых по схеме Кречмана
Authors: Петрин А.Б.
Published: November 2019

Based on the theory of reflection of a limited light beam from a plane-layered structure, the surface plasmon wave on the free surface of a gold film excited by the Kretschmann scheme is considered, as well as the surface wave in a planar surface waveguide for comparison. The sensitivity of optical sensors based on these surface waves is compared. Several methods are proposed for increasing the sensitivity of sensors based on surface waveguides. The necessary accuracy of manufacturing of the film thicknesses to obtain efficient sensors is estimated.
Использование микродисковых лазеров с квантовыми точками InAs/InGaAs для биодетектирования
Authors: Фетисова М.В. , Корнев А.А. , Букатин А.С. , Филатов Н.А. , Елисеев И.Е. , Крыжановская Н.В. , Редуто И.В. , Моисеев Э.И. , Максимов М.В. , Жуков А.Е.
Published: November 2019

The paper demonstrates the possibility of using microdisk lasers 10 µm in diameter with an active region based on InAs/InGaAs quantum dots synthesized on GaAs substrates for biodetection. As a detectable object we used chimeric monoclonal antibodies to the CD20 protein covalently attached to the surface of microdisk lasers operating under optical pumping at room temperature in an aqueous medium. It was shown that the attached secondary antibodies cause an increase in the threshold power of lasing and also to an increase in the half-width of the resonant laser line.
Деформация элементарной ячейки при прерывистом напылении пленок ниобата бария-стронция
Authors: Стрюков Д.В. , Павленко А.В.
Published: November 2019

The epitaxial Sr0.5Ba0.5Nb2O6/MgO thin films with different layer thickness, but the same total thickness have been fabricated by RF-cathode sputtering. It has been determined that layer thickness decreasement leads to an increase in the unit cell strain, which is maintained if the thickness of the subsequent layers does not exceed the critical.
Тритиевые источники электропитания на основе гетероструктур AlGaAs/GaAs
Authors: Хвостиков В.П. , Калиновский В.С. , Сорокина С.В. , Хвостикова О.А. , Андреев В.М.
Published: November 2019

We report on the development of a radioisotope power source based on the AlхGaAs1-х/GaAs semiconductor converter of β-radiation and tritium as a radiation source. The transducer efficiencies are compared for three types of β-radiation sources: (i) the tritiated titanium disk, (ii) the tritium lamp of green luminescent glow, and (iii) gaseous tritium. When using a converter based on the Al0.35Ga0.65As/GaAs heterostructure in a tritium capsule, the efficiency η = 5.9% is found with the maximum output specific electric power of 0.56 µW/cm2. Due to the prolonged operational life, such autonomous and compact power sources can be utilized in space technology, underwater systems, growth implants, biomedical sensors, and portable mobile equipment of high realibility.
Квантовый выход кремниевого XUV-лавинного фотодиода в диапазоне длин волн 320-1100 nm
Authors: Забродский В.В. , Аруев П.Н. , Бер Б.Я. , Казанцев Д.Ю. , Горохов А.Н. , Николаев А.В. , Филимонов В.В. , Шварц М.З. , Шерстнёв Е.В.
Published: November 2019

Silicon XUV avalanche photodiode prototype quantum yield have been explored with an active area of 1.5 mm in a 320 – 1100 nm spectral range. Quantum yield of a 20 electron per photon have been reached in 580 – 1000 nm spectral range with bias 485 V.
Широкополосные хаотические колебания в слабосвязанном ансамбле автоколебательных осцилляторов
Authors: Станкевич Н.В. , Попова Е.С. , Кузнецов А.П. , Селезнев Е.П.
Published: November 2019

A numerical study of van der Pol oscillators coupled in a ring is presented. The study of the characteristics of chaotic dynamics by analyzing the Fourier spectra and the spectrum of Lyapunov exponents is carried out. It is shown that the chaotic dynamics arising from the destruction of multi-frequency tori have a broadband spectrum.
Влияние формы канала на амплитуду случайных телеграфных шумов в подпороговой области беспереходного FinFET-транзистора
Authors: Халиллоев М.M. , Жаббарова Б.О. , Насиров А.А.
Published: November 2019

In this work it is simulated the random telegraph noise signal amplitude dependence on gate voltage overdrive for silicon on insulator junctionless FinFET transistor with fin cross section in rectangle and trapeze form. It is shown in subthreshold region the noise signal amplitude is lower in case of trapeze cross section of the fin. Besides it approximately at the same condition the noise signal amplitude is essentially lower in junctionless fin field effect transistor than in bulk, fully depleted silicon on insulator and ordinary fin field effect transistors.
Гетеромолекулы фрагмент графена-фрагмент даймондена, модифицированные металлами (Fe, Ni, Co)
Authors: Чекулаев М.С. , Ястребов С.Г.
Published: November 2019

We propose a model of heteromolecule based on Diamondene-Graphene hybrid with Hydrogen stabilized sp3-bonds. After stabilization we replased Hydrogen with metals (Fe, Ni, Co), optimization and stabilization of new molecules was estimated using the universal force field and ab initio methods. Stability of these heteromolecules shows that metals could be perspective for synthesys of Diamondene from Diamond.
Масс-спектрометрия молекул глутаминовой кислоты и глутамина в газовой фазе
Authors: Завилопуло А.Н. , Булгакова А.И.
Published: November 2019

The methodology and results of mass spectrometric studies of the yield of positive ions in the gas phase formed as a result of dissociative ionization of the amino acid molecules of glutamic acid and glutamine by electron impact are described. The experiment was carried out on a setup with a monopoly mass spectrometer of the MX-7304A type in the range of mass numbers 10–150 Da; the mass spectra of these molecules were studied at different temperatures. The features of the processes of formation of ion-fragments of glutamic acid and glutamine molecules by electron impact are analyzed in detail, and the dynamics of the yield of fragment ions in the range of evaporation temperature of the starting material 310–430 K is studied.
Увеличение фототока Ga(In)As-субэлемента в многопереходных солнечных элементах GaInP/Ga(In)As/Ge
Authors: Минтаиров С.А. , Емельянов В.М. , Калюжный Н.А. , Шварц М.З. , Андреев В.М.
Published: November 2019

An experimental and theoretical study of the spectral characteristics of the Ga(In)As subcell of the GaInP/Ga(In)As/Ge triple-junction solar cells has been carried out. It is shown that the use of a wide-gap “window” layer with an optimized thickness (Ga0.51In0.49P - 100 nm, Al0.4Ga0.6As - 110 nm, Al0.8Ga0.2As - 115 nm) for the Ga(In)As subcell allows increasing its photocurrent by about 0.5 mA/cm2, replacing the material of the back potential barrier of the GaInP subcell from Al0.53In0.47P to p+-Ga0.51In0.49P or AlGaAs allows increasing the short circuit current of Ga(In)As subcell by about 0.8 mA/cm2, and the use of the wide-bandgap Ga0.51In0.49P n++-layer in the tunnel diode instead of n++-GaAs increases the photocurrent by about 1 mA/cm2.
PENDETEKSIAN MINAT DAN BAKAT MENGGUNAKAN METODE RIASEC
Authors: Hidayat Fiyan Kurnia , Wahyuni Sri Ngudi
Published: November 2019

The interests are very important to choosing a course and field of work. Good salary, good company is one of goal in our life. One of many way which we can do for choice and mapping it more early is interest detection for detect our school and faculty which suitable with our interest. One of interest detection method use is RIASEC. RIASEC is one method with use probability principles for compute and compare six elements in it. The expensive price for buying a psychology expert is reason for developing this systems. The system can access bay website and which easy way. It will be helping all people for detection their children interest and will can giving best education for them.
PENGEMBANGAN SISTEM COMPUTER BASED TEST (CBT) TINGKAT SEKOLAH
Authors: Sugiyono Sugiyono , Sutarman Sutarman , Rochmadi Tri
Published: November 2019

Evaluation activities are part of the learning process at every level of education. The evaluation model or method also varies, from written tests to practical tests. Of the many evaluation methods, written evaluation or written test is an evaluation method that takes up a lot of paper, which is about 166 million pieces of paper for one national examination throughout Indonesia. The purpose of this study is to use a Computer Based Test (CBT) system that can be used as an alternative to overcome the problem of excessive paper use. The research method used in this study is R & D combined with ADDIE learning design concepts. This CBT system uses the PHP (Persolan Hypertext Preprocessor) programming language with a MySQL database connection to manage the content of the CBT system itself. This CBT system is intended for junior high / high school / vocational / equivalent levels with a trial percentage value of 83.34% for product validation test, 100% for operator user test and 88.94% for user test.
International pharmacy students’ transition to Nottingham: Semi-structured interviews (Preprint)
Authors: Liu Yicong
Published: November 2019

BACKGROUND

The transition from China to the UK can be challenging, and there is increasing concern among academics since cross-cultural learning and living may be a challenge for these students.

OBJECTIVE

To find out international pharmacy students’ worries and challenges as well as benefits on the transition experience from China to the UK.

METHODS

Semi-structured interviews were used to explore this group of students’ transition experiences. Selective transcription was done because of time limitations in the project.

RESULTS

The natural and cultural environment was the most pleasant experience for Tianjin students during this transition process. Cross-cultural adjustment and self-adaptability, as well as their autonomous learning ability were the main barriers for international students.

CONCLUSIONS

The difference between Asian and Western culture caused barriers for international students to fit into a new environment. In terms of integrating into local students, insufficient English language skills, culture shock and personality could be the influence factors. Moreover, the different teaching style and learning style could be the possible reasons for students having difficulty in an independent study.

CLINICALTRIAL

N/A
Efek kandungan serat beras analog terhadap ekspresi GLUT4 otot rangka tikus diabetes
Authors: Darajat Azka , Sakinah Elly Nurus , Hairrudin Hairrudin
Published: November 2019

Effect of analog rice’s fiber on skeletal muscles GLUT4 expression in diabetic rats Background: Disruption of glucose transportation in skeletal muscle through GLUT4 becomes a problem in diabetes. Analog rice that had been modified by adding dietary fiber could improve the expression of GLUT4.Objective: This study aims to know the effect of dietary fiber toward GLUT4 expression and to know the dietary fiber percentage in analog rice.Method: The research type is true experimental with post-test only group design. The samples consist of 24 male Wistar rats that are group into 4 groups (n=6 each group). Three groups were induced by giving a high-fat diet for 40 days and streptozotocin (STZ) 35 mg/kg BW was given at 33th day and one group was not induced. After the blood glucose level exceeded 135 mg/dl, the treatment was given. After 3 weeks, the rats were terminated and quadriceps femoris muscle tissue was taken for immunohistochemistry examination using rat GLUT4 polyclonal antibody. GLUT4 expression was quantified using an immunoreactive score (IRS-GLUT4). The data were analyzed using the Kruskal-Wallis test and Spearman test.Results: Statistical analyses showed that there were significant differences between groups with a moderate positive correlation (correlation coefficient=0,651; p=0,003).Conclusion: Dietary fiber in analog rice could improve skeletal muscle GLUT4 expression in Wistar rat diabetic model.
Peran kecambah kacang hijau (Phaseolus radiatus (L.)) pada sel lemak retroperitoneal tikus Sprague Dawley yang diberi diet tinggi lemak
Authors: Lestari Dwi , Lestariana Wiryatun , Lestari Lily Arsanti , Farmawati Arta
Published: November 2019

The role of mung bean sprouts (Phaseolus radiatus (L.)) on retroperitoneal fat cells of Sprague Dawley rats fed a high-fat dietBackground: The tendency of current lifestyles with high consumption patterns of fat is one of the factors causing obesity which is a risk of cardiovascular disease. Prevention of cardiovascular disease can be done by adopting a dietary pattern that is rich in antioxidants including consumption of sources of vitamin E. Sprouts from mung beans contain vitamin E and phytochemicals rich in antioxidants, so they can be used as an alternative to prevent hyperlipidemia sourced from daily functional food.Objective: To assess the effects of mung bean sprouts on retroperitoneal fat weight, cell number and cell diameter in rats fed high-fat feed.Method: This research is an experimental study with a post-test design with the control group. Thirty-four male Sprague Dawley rats ± 2 months old were divided into five groups, group I (standard feed), group II (high-fat feed), group III (high-fat feed and intervention of feeding tube of mung bean sprout 0.67 g/ 200 g BW), group IV (high fat feed and intervention of feeding tube of mung bean sprout 1.34 g / 200 g BW), and group V (high-fat feed and 23 IU dose of vitamin E supplement with feeding tube). After adaptation for three days, the intervention was carried out for four weeks. Analysis of fat weight, fat cell number, and fat cell diameter were done after the treatments. Data analysis using the One-Way ANOVA test. Results: Mung bean sprout dose of 1.34 g given for 4 weeks did not significantly decrease fat weight and cell number, but it decreased the diameter of retroperitoneal fat cells.Conclusion: Mung bean sprouts dose 1.34 g was better than a dose of 0.67 g and vitamin E supplementation in reducing the diameter of retroperitoneal fat cells in rats fed a high-fat diet.
State, Market and Citizens’ Sector in Post-Transition Societies: Towards an Inclusive Framework of Governance in Nigeria
Authors: Ozohu-Suleiman, Ph.D. Abdulhamid
Published: November 2019

The crisis of governance being experienced by states in the continent of Africa since the fourth quarter of the last century has provoked widespread debates on good governance and its requirements. These debates revolve around the premises of welfarism aimed at evaluating the capacity of the state to deliver existential requirements of citizens. The point at issues is that the most significant ends of good governance are citizens and their quality of life. Thus, in connecting government with the society as a whole (to secure this mandate), scholarly preoccupation has been on the changing tripartite relationship among the state, market and the citizens’ sector. This paper seeks to interrogate this relationship in Nigeria in terms of what has been achieved and the prospects for improved quality of governance, bearing in mind the constraints imposed by certain tendencies in the democratization process. It argues that the post-transition impact of civil society (broadly referred to as citizens’ sector), which constitutes a significant part of the environment in which the state operates has not received sufficient scholarly attention in states of Sub-Saharan Africa. The paper observes that the triumph of market economy and the concomitant shrinking of the state have significantly altered the institutional landscape of governance for the citizens’ sector to deepen its engagement with a trimmed government. In other words, outside the formal institutions of the state and market, the citizens’ sector has a crucial role to play in the good governance project. In states like Nigeria, liberal political conditions have provided the needed impetus for this inclusive framework of governance to flourish. It acknowledges that though, civil society (operating under a variety of organizations) has established its visibility in the political space, none-the-less, proactive and sustainable engagement with the state on policy issues is required to effectively drive the good governance project. Be that as it may, this paper recommends among others that the legal framework in respect of this tripartite relationship should be strengthened for optimal results, and that in (specific terms), in order to deepen the collaboration between the state and the citizens’ sector, the National Assembly should make law to provide a legal framework aimed at institutionalizing the Office of the Senior Special Assistance to the Presidents on Civil Society. This institutionalization will cascade into the role of civil society in the citizen engagement process.
Intervening Strategies to Cope with the Challenges of the Medium of Instruction of Instruction
Authors: Tibategeza Eustard Rutalemwa
Published: November 2019

English is a medium of instruction in higher learning institutions in Tanzania. Some institutions put in place some strategies to help students improve their English. This paper is a result of the study conducted at Archbishop Mihayo University College of Tabora. The objectives of the study were to assess the impact of the Basic English course on the students’ English, to scrutinise the course contents and to analyse the teaching methods and techniques to see if they help students to outshine in the English language. The study employed questionnaire, interview, focus group discussions and documentary review as instruments of data collection. The findings indicate that Basic English course has not helped students to improve their English for academic and professional communication and the course content is beyond what ought to be included in a basic course. It was further established that due to large classes, Basic English course is taught through lecture method, which does not give the students an opportunity to interact. The paper recommends that a serious review for Basic English course be done and be taught by qualified staff with appropriate teaching and learning materials in manageable groups to allow meaningful interaction and language usage.
Financiamiento de la educación elemental en Chiapas: dura tarea: (1880-1914)
Authors: Salinas Juan Manuel
Published: November 2019

Desde los albores de la Independencia de México, fuera de los múltiples problemas que aquejaban a la nueva nación, el de la educación era uno de los grandes retos a los que se enfrentaron las administraciones federales y estatales. A nivel nacional, conservadoramente, solo 20% de la población había gozado de este beneficio. El estado chiapaneco no fue la excepción. De acuerdo con las cifras del censo de 2010, Chiapas ocupa el primer lugar en analfabetismo a nivel nacional, seguido de Guerrero y Oaxaca. Aunque esta problemática tiene sus orígenes desde la Colonia, partiremos del periodo del porfiriato, etapa en que, bajo el concepto modernizador, la administración central se lanzó a la tarea de erradicar el atraso educativo en el país.
Advancing Children's Rights through the CRC: A Retrospective on the work of the Society for Children and Youth of BC
Authors: Neill James
Published: November 2019

This article traces the gradual adoption of the United Nations Convention on the Rights of the Child as a framework for action by one of B.C.'s longstanding charitable organizations advancing the well-being of children and youth, the Society for Children and Youth of BC. Using the four guiding principles of the Convention as a lens, this retrospective examines how the Society's projects have been informed by, and benefited from, the Convention.