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Objective.In most cases, when determining the stress-deformed state of three-layerstructures, it is assumed that bearing layers obey the Kirchhoff-Love hypothesis, while a filler obey theNeit (vanderNeit), or “broken line”, hypothesis. But in many cases, the results of our research showthat this is not always accurate.Methods.It is proposed to solve the three-dimensional problem of determining the stress-deformed state of a three-layer structure using cubic functions of the law of aggregate deformation distribution along the normal line, obtained on the basis of the law of deformation compatibility at “filler – bearing layer” boundaries and the construction of boundary conditions in joint zones.Results.Equilibrium equations of a three-layer beam obtained on the basis of thishypothesis are shown in Table 1. The given partial differential equations are of the 12th order and wetransformed them into homogeneous equations of the 1st order to simplify the solution. This solution isimplemented using the mathematical modelling software package Mаple 5.4.Conclusion.The work ofthe filler in the direction of OX axis has a certain value, which affects the overall stress state of thethree-layer structure (in existing hypotheses, it is zero).

Методом теории функционала плотности было выполнено теоретическое исследование нового слоевого полиморфа алмаза DL, состоящего из двух полимеризованных тетрагональных графеновых слоев L. Установлено, что новый алмазоподобный слой имеет двумерную тетрагональную решетку с параметром a = b = 0,3822 нм и толщиной 0,1599 нм. Рассчитанные поверхностная плотность и ширина запрещенной зоны этого слоя равны 0,109 мкг/см и 2,63 эВ, соответственно. Новый слой DL должен быть устойчивым, как минимум, до 220 К. Также установлено, что слой DL может быть получен при сильном одноосном сжатии двух графеновых слоев L при давлении 29,6 ГПа. Using the density functional theory method, a theoretical study of a novel layered DL polymorph of diamond, consisting of two polymerized tetragonal graphene L layers, was performed. It was established that the new diamond-like layer has a two-dimensional tetragonal lattice with the parameter a = b = 0,3822 nm and a thickness of 0,1599 nm. The calculated surface density and band gap of this layer are 0,109 μg/cm and 2,63 eV, respectively. The new DL layer must be stable up to at least 220 K. It was also found that the DL layer can be obtained by strong uniaxial compression of two graphene L layers at a pressure of 29,6 GPa.

We have calculated for the first time the conductivity of a submicron metal layer. A correction to the Wiedemann-Franz law is taken into account in the presence of specular-diffuse reflection of electrons.

The aim of the work, the results of which are presented in the framework of the article, was to study the of electromagnetic radiation interaction laws in the frequency range 0.7…17 GHz with two-layer structures, the surface layer of which was made using powdered titanium dioxide, and the inner layer was made using a powder material based on oxide ferric iron. The thickness of the layers of the studied structures varied from 0.3 to 1 cm. To achieve this goal, theobjectives associated with the development of a methodology for the manufacture of multilayer structures based on composite materials containing transition metal oxides, as well as with the measurement of such structures samples electromagnetic radiation reflection and transmission coefficients in the frequency range 0.7...17 GHz. These measurements were carried out using a panoramic meter of reflection and transmission coefficients SNA 0.01–17. Based on the obtained measurement results, it was shown that in the frequency range 0.7…2 GHz, the lowest values of electromagnetic radiation reflection coefficient, reaching –20 dB, are characterized by structures whose surface layer thickness is 1 cm, and in the range 2 ... 17 GHz – structures, thickness the surface layer of which is 0.5 or 1 cm (depending on the thickness of the inner layer). The values of electromagnetic radiation transmission coefficient in the frequency range of 0.7...17 GHz of such structures reach –23 dB. Based on the results of the study, it is proposed to use the considered structures in the process of creating shielded rooms or improving the latter (for example, in cases, when it's necessary to reduce the level of passive interference in rooms shielded with metal materials).

The transmission model for optical diapason was developed for multilayer coatings consisting of alternating layers of copper and zirconium dioxide deposited on K8 glass substrates. The model is based on the laws of light interference. It was shown that the transmission in the optical range of a 60 nm thick Cu layer with a surface resistance ρ = 1 Ohm/sq is 4–5 %, and the transmission of the ZrO2/Cu/ZrO2/Cu/К8 coating obtained by dividing a 60 nm thick copper layer into two sublayers at 30 nm with the application of antireflection layers of ZrO2 on them, at ρ = 1.2 Ohm/sq it reaches 25 %. The thicknesses and the number of layers of the Cu-ZrO2 system were calculated, which ensure a transmission in the wavelength range of 400–700 nm of at least 45 %. The permissible thickness of Cu layers (≥ 20 nm) was determined, below which, due to their insular structure and partial oxidation with the formation of Cu2O, the electrical conductivity of the multilayer coating sharply decreases (ρ ≥ 100 Ohm/sq).

A problem of efficient resource usage in road branch continues to be one of the most complicated issues and requires an intensification in investigation process pertaining to possibilities for production of road construction materials of low resource intensity with high physical and mechanical properties. Technogenic wastes of the Belarusian enterprises are rather various and they need a detailed investigation. Application of such methods as IR spectrometry, probe microscopy, study of of geometric characteristics of particles and fibers make it possible to determine more active centres and reveal micro-defects that influence on strength of adhesion bond at the boundary of “fiber – binder” and physical and mechanical properties of ready-mixed asphalt concrete. Nature of basalt fiber presupposes mainly physical character of adhesion interaction at the boundary of phase separation. An increase of technogenic waste activity to enhance adhesion contacts up to chemisorption level is possible only due to preliminary fiber processing which includes cleaning, removal of foreign inclusions, etching, drying, probable sorting-out and fluffing. Industrial approbation of such technological process is not possible without development of a corresponding module or a plant. Disperse reinforment causes changes in composition and technology of sand asphalt concrete. An increase in specific surface of an aggregate, necessity of uniform distribution of fiber in terms of volume determine the required need in a binder, procedure and regimes for component mixing. Grain composition of the aggregate can be represented by crush screening and natural sand of mixture of these materials. Requirements to properties of sand disperse-reinforced asphalt concrete are formed on the basis of operational conditions and layer arrangement of the material in the design of a surface dressing. The disperse-reinforced sand asphalt concrete can perform functions of a superfine protective layer, a levelling layer or a crack stopping layer which is resistant to fatigue crack formation.

Aim. To refine microanatomy of vitreoretinal interactions in central areas of retina and to obtain additional information on vitreoretinal interactions regarding theoretical possibility of collagen synthesis in the vitreous body of adult humans and mechanisms of vitreoretinal adhesion. Methods. Scanning electron microscopy study was performed in central areas of human retina after removal of vitreous base from its surface. Results. On the surface of retina we found a thin layer of epiretinal vitreous body most strongly bound to the retina. Thickness of paramacular epiretinal vitreous is 3–5 µm and it is formed mainly by thin densely packed fibrils. Its surface layer facing the vitreous cavity consists of the thickest (1 µm) and longest (250 µm) fibrils loosely packed. These fibrils look like “pearl threads” and exhibit signs of newly formed fibrils. Epiretinal layer of the vitreous in the fovea is thinner, its thickness is about 2 µm. Top layer of fibrils is least densely packed with the thickness of the fibrils of about 0.2 µm. The closer to internal limiting membrane, the thinner the fibrils, the denser their packing. The discovered layer can be interpreted as an additional anatomic structural unit of the vitreous body — epiretinal vitreous. Conclusion. We detected indirect signs of lifetime synthesis of newly formed fibrils in the vitreous of adult human; newly formed collagen may be localized in epiretinal vitreous which may be the main binding component providing vitreoretinal adhesion.

В работе представлены результаты исследования структуры и свойств бумажных обеззоленных фильтров «Синяя лента». Показано, что фильтровальная бумага «Синяя лента» имеет достаточно высокую плотность с относительно малым количеством и размеров пустот (пор) между волокнами. При обработке фильтров в поле коронного разряда наблюдается повышение их механических свойств на 3.5–6%, что вызвано преимущественно усилением межволоконных сил связей. Реализация повышенных электростатических сил связей в структуре листа приводит к увеличению сопротивления внешней растягивающей силе, необходимой для разрыва бумажного фильтра. Наблюдаемые зависимости связаны с ориентацией и упорядочиванием элементов структуры целлюлозно-бумажного материала, с ростом потенциала двойного электрического слоя на поверхности волокон под действием носителей заряда, инжектируемых в объем бумаги из коронного разряда и с образованием гетерозаряда за счет ориентации полярных группировок целлюлозы, сегментов макромолекул во время электретирования. Это подтверждается ростом ζ-потенциала волокон обеззоленных фильтров при обработке в отрицательном коронном разряде – установлено, что значение дзета-потенциала волокон электретированных обеззоленных фильтров на 18% больше, чем для исходных. Достигнутые результаты увеличения физико-механических свойств обеззоленных фильтров позволят повысить эффективность их применения., The article presents the study results of the structure and properties of paper ashless filters "Blue tape". It is shown that the "Blue tape" filter paper has a fairly high density with a relatively small number and size of voids (pores) between the fibers. When processing filters in the corona discharge field, an increase in their mechanical properties by 3.5–6% is observed, this is mainly due to the strengthening of the interfiber bond forces. The implementation of increased electrostatic bonding forces in the sheet structure leads to an increase in the resistance to the external tensile force necessary to break the paper filter. The observed dependences are associated with the orientation and ordering of the pulp and paper material structural elements, with an increase in the potential of the double electric layer on the fibers surface under the charge action carriers injected into the paper volume from the corona discharge and with the formation of a hetero charge due to the orientation of the polar cellulose groups and macromolecule segments during electreting. This is confirmed by the increase in the ζ – potential of the fibers of filters during processing in a negative corona discharge - it was found that the zeta – potential value of electret ashless filters is 18% higher than for the initial ones. The achieved results of increasing the ashless filters physico- mechanical properties will increase the efficiency of their use.

Проведено механико-математическое моделирование селективного водозаборного процесса в трехслойном стратифицированном водоеме, когда вода забирается из внутреннего объема промежуточного слоя водоема. Составленная математическая модель представляет контактную начально-краевую задачу теории поверхностных и внутренних гравитационных волн в идеальной несжимаемой жидкости. Водозабор из внутреннего пространства промежуточного слоя смоделирован в виде объемного стока с бесконечно малой толщиной и конечным сточным расходом. В результате решения поставленной начально-краевой задачи получена система расчетных формул, которая с привлечением компьютерных средств позволяет выбирать диаметр водозаборной трубы и расход через нее, вычислять отметку глу- бинного расположения конца водозаборной трубы. Выбор этих параметров обеспе- чивает селективный водозабор исключительно из промежуточного слоя, где вода чище и холоднее, чем в других слоях водоема., The purpose of this work is to carry out mathematical modelling of selective water intake process in a three-layer stratified reservoir, when the water is taken from the interior volume of the intermediate layer of the reservoir. In the methodology for solving the problem, the water intake from the interior volume of the intermediate layer is modelled as a finite flow rate drain of fluid trough an infinitely thin layer. The contact initial-boundary value problem of the theory of surface and internal gravitational waves in an ideal incompressible fluid is used as a mathematical model of the water intake process. As a result we obtain a system of calculation formulas for estimation of the diameter of water intake pipe and the flow rate through it. The depth mark of the end of the water intake pipe was calculated. Originality/value: 1. The boundary value problem simulating a selective water intake process from the internal volume of the intermediate layer of a three-layer stratified reservoir was formulated and solved. 2. On the basis of the obtained set of formulas, computer experiments were performed and thus the regularities of the influence of the above external input parameters on the process were established. 3. The choice of these parameters provides selective intake exclusively from the intermediate layer, where the water is cleaner than in the lower layer and colder in summer than in the upper layer., №25 (2020)

При раскопках стоянки Береговая II на Горбуновском торфянике в Зауралье в слое позднего мезолита был найден перфорированный диск-навершие из тальк-хлоритовой горной породы. На лицевой стороне диска грубой шлифовкой моделирован выступающий нос, гравировкой показаны брови, усы и борода личины. Отверстие для рукоятки в центре расположено на месте рта. Всего в Зауралье известно 4 крупных перфорированных диска, которые исследователи относили к эпохе бронзы и интерпретировали как диски-календари. Отличительные черты нашего диска позволяют считать его скорее навершием ритуального оружия типа булавы. Находка подобного артефакта в четких стратиграфических условиях – в культурном слое позднего мезолита стоянки Береговой II – и сходство отдельных деталей антропоморфной личины на диске с деталями лица Большого Шигирского идола доказывают гораздо более раннее их бытование в Среднем Зауралье., The excavations at the Beregovaya II site in the Gorbunovo peat-bog in the Transurals yielded a perforated end-piece disc made from talc chlorite rock. The face side of the disc features a protruding nose made by rough grinding, whereas the brows, the moustache and the beard of the human-like mask are rendered by engraving. There is a shaft-hole in the center where there should be the mouth. Totally four large perforated discs referred by researchers to the Bronze Age and interpreted as calendar discs that are known in the Transurals region. The distinguishing features of this finial-disc suggest that, most likely, it was a part of a ceremonial weapon such as a macehead. The find of this artifact in the clear stratigraphic context of the Late Mesolithic occupation layer at Beregovaya II and similarity between some parts of the anthropomorphic human-like mask on the disk and the face of the Big Shigir idol is an evidence that such discs were used in the Middle Transurals much earlier., Краткие сообщения Института археологии (КСИА), Выпуск 259 2020

В статье рассматривается коллекция перфорированных раковин пресноводных моллюсков, происходящих из верхнепалеолитического культурного слоя пещеры Двойная (Северо-Западный Кавказ). Приведена характеристика видового состава моллюсков, описаны их морфологические особенности и реконструированы способы перфорирования. Трасологический анализ позволил выявить, что помимо перфораций, совершенных человеком, на раковинах есть следы природного сверления, связанные, предположительно, с деятельностью неизвестного хищника, а также следы «погрызов» неустановленного генезиса. Свидетельства сверления раковин пресноводных моллюсков хищниками редки и плохо изучены. Характер следов износа поверхности раковин позволяет с наибольшей долей вероятности реконструировать их использование в качестве бусин в составе ожерелья, браслета или пронизок в декоративном оформлении одежды., The paper examines the collection of perforated shells of fresh-water mollusks found in the Upper Paleolithic occupation layer in Dvoynaya Cave (the northwestern Caucasus). It provides characteristics of mollusk species, describes their morphological traits and reconstructs methods of perforation. The tracewear analysis evidences that, in addition to perforations made by humans, the shells bear traces of biotic drilling, supposedly, left by an unknown predator as well as biting marks of unidentified origin. Evidence of drilling predation found on the shells of freshwater mollusks is not ample and well-studied. The nature of wear traces on the shell surface makes it possible to reconstruct their use as beads of a necklace, a bracelet or tubular beads used as elements of clothes decorative design., Краткие сообщения Института археологии (КСИА), Выпуск 259 2020

The paper provides experimental and theoretical study of pHEMT heterostructures with quantum well (QW) AlGaAs/InGaAs/GaAs and delta-doped layer used as active layers for fabrication of 4-18 GHz transistors. As the experimental techniques, the electrochemical capacitance-voltage (ECV) profiling and other methods of admittance spectroscopy are applied. Modernization of commercial ECV-profiling setup allows observing for the first time the concentration peak from a near-surface delta-layer of pHEMT heterostructures together with the enrichment peak from the quantum well. In order to optimize the etching speed the crater bottom control is performed by means of AFM. The electrolyte-semiconductor contact capacitance is measured with Agilent RLC-meter. The main theoretical technique used in the research is numerical modeling of nanoheterostructure key electronic features by self-consistent solution of Schrödinger and Poisson equations. The potential line-up for the conduction band bottom is obtained, and the quantized energy levels are calculated. The complex analysis of series of samples is carried out in order to understand the influence of delta-layer position on the level depth and at the carrier concentration. The optimum distance between QW and delta-layer providing the most efficient charge carrier delivery to quantum well is found. The performed research is aimed at improvement of microwave electronic devices allowing increase of the gain coefficient and the transfer characteristic of SHF-transistors.

The algorithm for calculating electrodynamic characteristics of hybrid types of waves propagating in double ridged waveguide with piecewise-layered dielectric filling is presented. The double ridged waveguide structure with dielectric plates installed between the ridges, and with dielectric sample sandwiched between the dielectric substrates is consid-ered. The calculations are carried out using the method of partial regions. The presented algorithm takes into account the electromagnetic field components singularities near the dielectric and metal edges of the waveguide. The technique for calculating the electromagnetic energy losses in the double ridged waveguide with a piecewise layered dielectric filling is provided. The classification of hybrid waves is given. The spatial structures of electromagnetic fields and their planar projections (front view, top view, side view) for the first two HEwaves and the first EH-wave are demonstrated. Cutoff fre-quencies and propagation constants of HEand EH-waves are calculated. The results obtained using the described meth-od and numerical approach are compared. Then the results are analyzed.

At the choice of the mode of safe drying of grain mass it is necessary to consider its heterogeneity on moisture content. It is an undesirable factor of which it is necessary to get rid. When increase in moisture inconstant the stability of grain mass at storage decreases, there is a danger of emergence of heating, the overall performance of dryers and other processing equipment decreases, energy costs for seeds production rise. To eliminate this shortcoming located in a grain layer or grain stream the dried-up product should be mixed carefully for the best uniformity. However not uniformity on individual moisture content of separate grains will remain. For its decrease combination of lying with material concitation is used. Researches were conducted in batch-operated laboratory machine. The humidified seeds of sugar beet were blowed-through with the drying agent speed of 0.5 m/s and temperature of 45 degrees Celsius. Moisture removal between concitations did not exceed 2.5 percent for selection seeds and 3.0 percent for ordinary ones. Duration of the periods between concitations can be determined in the analytical way. Thickness of a layer of seeds allowing drying without concitation decreases on square dependence on increase in moisture content. A contact moisture exchange between the damp and dried caryopsides for 30 min and more make it possibledrop-off in the unevenness of drying up to 0.5 percent.

Titanium alloys due to their properties are of great interest for use as a structural material for the parts of friction units, pump plungers, shaft-bush parts operating in harsh environments. But high tendency of titanium alloys to the contact seizure under friction restricts wider application of titanium and its alloys. One of the main ways to improve the anti-friction properties of titanium alloys is a chemical heat treatment. The most common type is nitrogen hardening that allows us to achieve high values of micro-hardness on the surface. However, the biggest drawback of the method is small depth of the hardened layer that is up to 0.16 mm. To increase a depth of the hardened layer the paper proposes the preprocessing of the part surface by deformational cutting, which allows creating a macro-relief of different shape as the alternate vertical or inclined layers of the part material of a specified thickness and height with a gap or no gap between the layers. Doping of this structure, when nitriding, is provided over the entire macro-pattern surface, thereby enabling to obtain a thickness of the hardened layer, which depends on the processing parameters in deformational cutting. The paper presents the results of the microstructure study and the micro-hardness measurements of the VT1-0 titanium alloy sample after deformational cutting process followed by nitriding. The influence of the deformational cutting parameters on the total thickness of the hardened surface layer is analyzed. It is found that the entire surface of macro-pattern has been azotized. The total thickness of the nitrogen hardened modified surface structure became 4 times larger as compared to the flat surface that was azotized. The results can be used as a theoretical basis to design the titanium alloy parts operating in conditions of friction.

В статье рассматриваются отдельные аспекты феномена культурного слоя. Это, по мнению автора, бинарное образование, доминирующую роль в сложении которого играют природные процессы. Критика взглядов разных исследователей позволяет обосновать особенности и содержание данного феномена и предложить вариант его определения., The paper reports on some aspects of the phenomenon of the occupation layer. In the view of the author, it is a binary formation, with natural processes playing a dominant part in its development. The critical review of opinions expressed by various researchers makes it possible to justify specific features and substantive elements of this phenomenon and suggest its definition, №256 (2019)

Предложен новый алгоритм определения значений экстремумов измеряемой в процессе напыления многослойного покрытия зависимости значения коэффициента отражения от оптической толщины напыляемого слоя. Алгоритм использует физическую модель процесса напыления, что позволяет использовать все данные измерений, накопленные регистрирующим прибором во время напыления слоя, в отличие от классических подходов, которые хорошо описывают зависимость коэффициента отражения только вблизи ее экстремума. Эффективность предложенного подхода продемонстрирована на примере моделирования процесса напыления 20слойного четвертьволнового зеркала., A new algorithm for determining the extrema in the dependence of the reflection coefficient on the optical thickness of the deposited layer is proposed. This reflection coefficient is measured during the deposition process of a multilayer coating. The proposed algorithm uses a physical model of the deposition process, which makes it possible to use all the measurement data accumulated by a recording device during the deposition of the layer in contrast to the classical approaches that adequately describe the dependence of the reflection coefficient only near its extremum. The efficiency of the proposed approach is shown by an example of modeling the deposition process for a 20-layer quarter-wave mirror., ВЫЧИСЛИТЕЛЬНЫЕ МЕТОДЫ И ПРОГРАММИРОВАНИЕ: НОВЫЕ ВЫЧИСЛИТЕЛЬНЫЕ ТЕХНОЛОГИИ, Выпуск 4 2019

В ходе раскопок на городище Фанагории в 2019 г. вдоль восточного борта раскопа Нижний город был вскрыт слой пожара 6 в., в котором погибли здания, в одном из них находилась винодельня. Среди самых ярких находок солид Юстиниана I (527565), имеющий определяющее значение для датировки катастрофы. Солид отчеканен в 6й оффицине Константинопольского монетного двора в 542565 гг.н.э. В Фанагории, как и в других боспорских городах и поселениях, археологически фиксируются два слоя пожаров 6 в. Во второй четверти 6 в. город подвергается разгрому и разрушению, о чем свидетельствует первый слой пожара, в котором найдены снаряды от метательных машин. Эти события связывают с восстанием против вассала Византии гуннского вождя Грода в 528 или 534 г. Второй слой пожара в Фанагории датируется последней четвертью 6 в. и связывается с событиями 576 г. походом тюрок на Боспор, когда пострадала большая часть крепостей и малых городов Керченского и Таманского полуостровов. Датировка солида Юстиниана I из слоя разрушений подтверждает, что мы имеем дело со вторым пожаром 6 в. После 560 г. на Боспоре Киммерийском появились теснимые тюрками авары на своем пути на Истр, откуда они отправили посольство к Юстиниану I. Вслед за аварами на азиатский берег пришли тюрки, которые затем в 576 г. осадили и взяли Боспор (Керчь). Таким образом, находка солида Юстиниана I в слое пожара связана со временем прихода на Тамань аваров в середине 6 в. или тюрок в 570х годах. Прибытие и тех и других неминуемо несло внешнюю угрозу Боспору, в том числе и Азиатскому. Но кто именно авары или тюрки разрушили Фанагорию, остается пока неизвестным., During excavations in Phanagoria in 2019, a burnt layer of the sixth century was recovered along the east edge of the trench Lower City, containing buildings destroyed by the fire, among them a winery. There is a solidus of Justinian I (527565) among the most prominent finds, providing the date for catastrophe. The solidus was struck in the sixth officina at the Constantinople mint in 542565. There are two sixth century burnt layers discovered in Phanagoria, as well as the other Bosporan cities and settlements. In the second quarter of the sixth century the city was burnt and destroyed, that is testified by the first burnt layer containing missiles for siege engines. These events could be connected with the rebellion against Hunnish chief Grodes, the Byzantine vassal, in 528 or 534. The second burnt layer in Phanagoria is dated to the last quarter of the 6th century, in connection with the events of 576, when the Turks attached most of the fortresses and small towns on the Kerch and Taman Peninsulas. The date of Justinian Is solidus from the burnt layer points to the second great fire in the late 6th century. After 560, the Avars pressed by the Turks on their way to the Istrum (Danubius) arrived at the Cimmerian Bosporos, where from they sent an embassy to Justinian I. Soon the Avars were followed by the Turks who in 576 besieged and occupied Bosporos (Kerch). Consequently, the find of the solidus of Justinian I in the burnt layer can be connected with the arrival of the Avars in the middle of the 6th century, or the Turks in the 570-s. Both peoples offered a threat for Bosporos, especially its Asiatic part. It is not clear, however, who actually destroyed Phanagoria, the Avars or the Turks

Цель исследования – изучение динамики прогрева одиночного высоковлажного куска древесной коры, находящегося в плотном слое продуваемом высокотемпературным теплоносителем. Проведен анализ энергетического использования древесной коры в процессе ее сжигания слоевым способом в топках теплогенераторов. Выявлены условия эффективного использования древесной коры в качестве топлива. Разработана математическая модель прогрева куска высоковлажной коры древесины, находящегося в плотном слое продуваемом высокотемпературным теплоносителем. Проведено исследование динамики прогрева кусков высоковлажной древесной коры в форме параллелепипеда и эквивалентного шара. Разработана методика оценки времени прогрева куска коры, находящегося в неподвижном нагреваемом плотном слое. Численным методом получены математические зависимости, позволяющие определить время нагрева поверхностного слоя куска коры до температуры начала выхода летучих веществ. Окончательные соотношения приведены к безразмерному виду и выражены через числа Фурье и Коcсовича. Полученные соотношения учитывают геометрические размеры куска коры, его исходную влажность и параметры греющего теплоносителя. Практическим приложением результатов настоящих исследований является организация топочного процесса в котельном агрегате., The purpose of the study is to study the dynamics of heating a single piece of high – moisture tree bark located in a dense layer of blown, high-temperature coolant. The analysis of the energy use of wood bark in the process of its burning in a layered way in the furnaces of heat generators. The conditions of effective use of wood bark as fuel are revealed. A mathematical model of warming up a piece of high-moisture bark of wood located in a dense layer of blown, high-temperature coolant. The study of the dynamics of warming pieces of high-moisture tree bark in the form of a parallelepiped and an equivalent ball. The method of estimation of time of warming up of a piece of bark which is in a stationary heated dense layer is developed. The mathematical dependences allowing to determine the time of heating the surface layer of a piece of bark to the temperature of the beginning of the exit of volatile substances are obtained by numerical method. The final relations are given to a dimensionless form and expressed in terms of Fourier and Kosovic numbers. The obtained ratios take into account the geometric dimensions of the piece of bark, its initial moisture and the parameters of the heating coolant. Practical application of the results of this research is the organization of the combustion process in the boiler unit., №225 (2018)

The paper proposes a method for depth measurement of a disrupted layer on silicon wafer surface which is based on application of Auger spectroscopy with the precision sputtering of surface silicon layers and registration of the Auger electron yield intensity. In order to measure the disrupted layer with the help of Auger spectroscopy it is necessary to determine dependence of the released Auger electron amount on sputtering time (profile) and then the dependence is analyzed. Silicon amount in the disrupted layer is less than in the volume. While going deeper the disruptive layer is decreasing that corresponds to an increase of atom density in a single layer. The essence of the method lies in the fact the disruptive layer is removed by ion beam sputtering and detection of interface region is carried out with the help of registration of the Auger electron yield intensity from the sputtered surface up to the moment when it reaches the value which is equal to the Auger electron yield intensity for single-crystal silicon. While removing surface silicon layers the registration of the Auger electron yield intensity from silicon surface makes it possible to control efficiently a presence of the disrupted layer on the silicon wafer surface. In this case depth control locality is about 1.0 nm due to some peculiarities of Auger spectroscopy method. The Auger electron yield intensity is determined automatically while using Auger spectrometer and while removing the disrupted layer the intensity is gradually increasing. Depth of the disrupted layer is determined by measuring height of the step which has been formed as a result of removal of the disrupted layer from the silicon wafer surface. Auger spectroscopy methods ensures an efficient depth control surface disruptions at the manufacturing stages of silicon wafers and integrated circuits. The depth measurement range of disruptions constitutes 0.001–1.000 um.

Fire-retardant composites with the application of gypsum, unslaked lime, distended vermiculite, tuffaceous sand, basaltic fibers and resin of wood of that saponified are developed. The methods of the preparation of fire-retardant mixture and molding of articles made of the composites are investigated. Are given the results of experimental and theoretical studies of the fire resistance of armotsementnykh elements with the fire-retardant layer from the gipsovermikulitotufobetonnykh and fibrogipsovermikulitotufobetonnykh composites.

Influence of snow cover, climate and glacier parameters on the cold-ice layer thickness and thermal regime in the ablation area of a polythermal glacier in Western Svalbard was investigated. Numerical modeling has demonstrated that a thickness of a cold layer in a polythermal glacier depends on a relation between the ablation on the surface and the freezing rate at the layer base. If the ablation rate is lower than that of the freezing, the layer thickness grows until the ablation and freezing rates become equal. Estimations show that in a case of slightly negative air temperatures on the glacier its cold-ice layer thickness increases when the snow cover thickness grows.

The paper concerns modeling of an uneven flow and electromagnetic field parameters in the combustion chamber of the liquid rocket engine with a near-wall layer available.The research objective was to evaluate quantitatively influence of changing model chamber mode of the liquid rocket engine on the electro-physical characteristics of the hydrocarbon fuel combustion by-products.The main method of research was based on development of a final element model of the flowing path of the rocket engine chamber and its adaptation to the boundary conditions.The paper presents a developed two-dimensional non-stationary mathematical model of electro-physical processes in the liquid rocket engine chamber using hydrocarbon fuel. The model takes into consideration the features of a gas-dynamic contour of the engine chamber and property of thermo-gas-dynamic characteristics of the ionized products of combustion of hydrocarbonic fuel. Distributions of magnetic field intensity and electric conductivity received and analyzed taking into account a low-temperature near-wall layer. Special attention is paid to comparison of obtained calculation values of the electric current, which is taken out from intrachamber space of the engine with earlier published data of other authors.

Now curved cutting edge mills are widely used. A section of the cutting layer (chip load), when using such mill, is a curvilinear polygon, usually, limited to four curves. Thus, a size of the taken chip is various for different points of the cutting edge. There are a lot of analytical and empirical relationships to calculate a cutting force. However, they cannot be used for this purpose with a variable chip load thickness.The Sandvik company wavy cutting edge mill Preci Tool 166205 (a mill diameter d = 10 mm; the teeth number z = 4) with the milling width d/2 and feed per tooth Sz = 0.042 mm/tooth was used as a model object. To calculate a cutting force the formula c1.1 m k P A a  was used where A, a are the chip load area and thickness; kс1.1 is the specific cutting force (for steel kс1.1 =2000 N/mm2 ); m is coefficient (for steel m = 0.26).For calculating a cutting force in case of the curved chip load four techniques were used. They were distinguished by a way of splitting the chip load into sectors and defining its thickness.1. Splitting the chip load into the sectors, which are limited on two sides to curves, and on two other sides to converging straight lines, perpendicular to a trace of the cutting edge, allowed to calculate theoretically correct cutting force. It is shown that with increasing number of splitting sectors a cutting force a little decreases, and then is stabilized at the level of 160.5 N. This value can be considered to be the valid cutting force arising when there is a curved chip load.2. When splitting the chip load into trapezes a cutting force increases with increasing number of splitting segments and tends to the value of 165.5 N. Replacing the curved sectors with trapezes enables an error in cutting force calculation to be 3.1%. Such error allows us to claim that for engineering calculations it is admissible to make the specified simplification.3. For simplification of measurements and calculations of cutting force it was offered to make splitting the chip load by the lines located radially with respect to the mill (perpendicular to the mill axis). The cutting force calculated for such way of splitting essentially does not depend on the number splitting segments (change of force values was at most 0.2%). An error of determined cutting force thus is 1.5% that allows us to draw a conclusion that radial splitting can be used for calculation of cutting force with curved chip load.4. The integrated calculation of cutting force for the chip load area and width or a trace length of the cutting edge give an error rate of 5 and 7% (168,3 N and 172 N), respectively, that allows to recommend such calculations only as integrated, preliminary.

The numerical model of sedimentation and suspension filtration is proposed in this paper. The model is based on dynamic variant of discrete element method. This model represents the particles behavior on microand meso-scales: pores, arches, flocks formation. In addition, the proposed model qualitatively reproduces macro phenomenon: sedimentation of particle layer, slow shrinkage of the layer, sealing of the layer under its own weight of the particles and the external applied force.

В настоящей работе исследовано влияние ƴ‐излучения на процесс окисления Ni-P химически осажденного покрытия на нержавеющей стали марки 304 методом сканирующей электронной микроскопии (SEM) и рентгеновского анализа (EDX). Установлено, что после ƴ-излучения поверхность Ni-P слоя былa полностью покрыта трещинами, и на поверхности Ni-P слоя обнаружено высокое содержание кислорода и фосфора из-за образования оксида Р2О5., The given work deals with the effect of gamma-irradiation on the oxidation process of the Ni-P chemical deposition on the surface of the stainless steel marked 304. The methods used are scanning electron microscopy and X-ray analysis. As a result, it has been found out that after gamma-irradiation the surface of the Ni-P layer is completely covered with cracks, and on the surface of this layer a high content of oxygen and phosphor has been detected because of formation of the P2O5 oxide.

Техногенное воздействие человека на литосферу приводит к крупномасштабным изменениям в при- родной среде, активизирует развитие в ней ряда опасных процессов и служит причиной появления новых природно-техногенных явлений. В процессе поисков полезных ископаемых с целью заверки геофизических аномалий и уточнения их природы на Джимидонском участке была проведена литогеохимическая съемка по профилям. По результатам обработки геохимических данных было выделено 5 мультипликативных ореолов (аномалий). Сопоставление всех количественных геохимических и геофизических характеристик, позволяет сделать вывод, что некоторые геохимические аномалии, выявленные на Джимидонском месторождении, скорее всего, техногенного происхождения, образованные при транспортировке руды в результате ее потери и складирования, а также при разработке разведочных выработок, The technogenic action of man on the lithosphere leads to the large-scale changes in the natural medium, activates the development in it a number of dangerous processes and serves as a reason of the new naturaltechnogenic phenomena appearance. In the process of the mineral searches for the purpose of geophysical anomalies verification and refinement of their nature in the Dzhimidon site was the lithogeochemical survey along the profiles carried out. According to the results of geochemical data processing were isolated 5 multiplicative halos (anomalies). The comparison of all quantitative geochemical and geophysical characteristics, makes it possible to draw the conclusion that some geochemical anomalies, revealed on the Dzhimidon layer, most likely, has the technogenic origin, formed with the transport of the ore as a result of its loss and storing, and also with the development of prospectings, Геология и геофизика Юга России, Выпуск 4 2014

Ab-intio study of the interaction of atomic and molecular oxygen with the TiNi(1 1 0) surface was performed using the projector augmented wave method with generalized gradient approximation for the exchange-correlation functional. The oxygen adsorption energies were calculated and the preferential adsorption sites of oxygen atom on the surface were determined. Our results confirmed the formation of a Ni-rich layer at the alloy–oxide interface. Atomic and electronic structure of both TiO/TiNi(1 1 0) and TiO2/TiNi(1 1 0) interfaces were analyzed. The formation energies (Ef) of point defects at the interfacial layers as well as in bulk TiNi, monoclinic TiO, and rutile TiO2 were estimated. It was shown that Ef of Ti–Ni swap defect has a lower energy than that for the Ni antisites at the TiO2(1 0 0)/TiNi(1 1 0) interface. In the case of TiO(1 0 0)/TiNi(1 1 0) interface, the formation energies of Ti–Ni swap and Ni-antisites defects are close to each other. Our results demonstrated that Ef of Ni-defect in TiO is twice less than that in TiO2. The increase in the formation energies of defects in TiO2 reveal the increase in diffusion barriers of Ni atoms in comparison with those in oxides with a lower oxygen content, which hampers Ni segregation.