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The paper considers technological features of heterogeneous plastics ultrasonic welding, which specificity is manifested in the volumetric interaction nature. Results of studying the mechanism of a welded joint formation showed that micro-volumes mixing, polymer molecules mutual diffusion in the contacting surfaces and emergence of the new chemical bonds with the block copolymers formation were the simultaneous processes. Their common feature was that all these processes proceeded in the temperature range corresponding to the polymer viscous-flow state. It was experimentally confirmed that one of the criteria for weldability of the heterogeneous plastics was their compatibility in terms of acoustic properties being estimated by the melt density and viscosity. Technological methods were proposed making it possible to compensate for differences in the welded materials acoustic properties, and thereby obtain the high-quality welded joints. Four stages of the welded joints formation mechanism were determined during ultrasonic welding of the heterogeneous plastics. It was established that physical and mechanical properties of the heterogeneous plastics were playing a decisive role in the mechanism of heat generation during the ultrasonic welding. An ultrasonic welding unit for welding the heterogeneous plastics in vacuum was developed.

It was established that the mode parameters determining efficiency of the plastics ultrasonic welding process include waveguide oscillation amplitude, welding static pressure, oscillation frequency, welding time and size of the fixed gap between the waveguide working end and the support. In each specific welding mode, an increase in the gap of more optimal value leads to a decrease in the breaking load; this is especially true in welding products of higher thickness. Welding could be performed on surfaces coated with various products. An expression was obtained to determine time and intensity coefficients of the ultrasonic welding mode. Fixture supports influence on quality and strength of the welded joints in the ultrasonic welding of polymeric materials was considered. When using an active support, strength and productivity of ultrasonic welding was much higher than in using the passive supports. Results of the experiments confirmed the relationship between the support oscillations amplitude and the heating, thickness and properties of the parts to be welded. A working cycle of the plastics ultrasonic welding is proposed, where the static welding pressure and the ultrasonic pulse time are ensuring maximum strength and tightness of the welded joint.

The main goal of this paper is to consider formulation and solution of a lubrication problem based on the expressions for elastic surface displacements derived asymptotically from an exact solution for a loaded double coated elastic substrate which are valid within a certain region of the problem input parameters. Therefore, a new relatively simple numerical model of the behavior of lubrication parameters in a line lightly loaded contact of double coated elastic cylinders has been developed. For simplicity materials and coatings of both cylinders are considered identical. The main part of the elastic displacements of the contact surfaces is represented by simple Winkler like contributions. The problem is reduced to a numerical solution of a system of two transcendent equations. The formulas for lubrication parameters such as distributions of contact pressure, gap, lubrication film thickness, shear stress, coefficient of friction, and contact energy loss were derived and used for specific calculations. Generally, compared to lubrication parameters in the contact of rigid solids without coatings the effect of the double coating resulted in reduced (up to 60% or more) contact pressure, increased contact area and film thickness as well as some reduction of frictional forces and energy losses. Some specific results for the obtained solutions are provided.

The paper presents a description of a case of successful one and a half ventricular correction of a complex congenital cardiac anomalies, including the common atrioventricular canal, tetralogy of Fallot, and hypoplasia of the right ventricle in a child (2 year and 4 months). Ararecongenitalanomalycharacterized by acombinationof intracardiac defects, required an innovative surgical approach, the exclusivity of this clinical case has determined. The surgical strategy of complete atrioventricular canal defect is determined by a number of factors. One of the most important is balance between right and left ventricular outputs. The balanced type with adequate development of the ventricles involves the biventricular repair performance. Unbalancedatrioventricular canal defects includea hypoplastic ventricle. Reconstructive surgeryfor onehypoplasticventricle is oriented towards the degree of hypoplasia. In particular, a mild right ventricular hypoplasia allows perfoming biventricular radical operation while a severe degree suggests univentricular repair. In case of borderline, moderate degree of hypoplastic right ventricle the one and half ventricle repair can be carried out. Another important point is the presence of concomitant pulmonic stenosis required the choice of optimal method and material for reconstruction which is not always obvious and often it is the subject of debates. This report presents a description of the diagnostic stages with an emphasis on determining the type of balance of the common atrioventricular canal, the degree of hypoplasia of the right ventricle, the approach to choosing the optimal method for correcting the defect in general and the material for reconstructing the outflow pathway from the right ventricle in particular, as well as the subsequent successful correction of congenital multicomponent cardiac abnormalities in a young patient.

The present paper is devoted to the construction of the approximate solution of the contact problem on a conical punch indentation into an elastic isotropic half-space with coating. The solution is suitable for both homogeneous (when elastic moduli are constant) and multilayered or functionally-graded coatings (when elastic moduli change with depth). The solution was obtained using the bilateral asymptotic method in the analytical form. The kernel trans-form approximation was obtained as the ratio of two quadratic functions and contains only one parameter. Thus, the scheme of the approximate analytical solution was constructed in a significantly simplified manner in comparison with the general case in which the product of fractional-quadratic functions is used. Such an approach allowed us to obtain explicit analytical expressions for the distribution of contact stresses and the force-displacement dependences in a simplified form, convenient for engineering calculations. The influence of the parameter characterizing the relative Young's modulus of the coating on the characteristics of contact interaction was analyzed. The accuracy of the obtained solution was studied depending on the ratio of the elastic moduli of the coating and the substrate using a series of homogeneous coatings as an example. Particular attention was paid to the investigation of the indentation stiffness - the most important characteristic used in experimental researches. The results of the work can be used to describe an experiment on nanoindentation of materials with coatings using either a conical or a Berkovich indenter.

This paper presents a mechanism of formation of a hard-to-weld polycarbonate joint by ultrasonic welding. The method utilizes internal and external friction occurring in the welded joint area on abutting surfaces due to shear vibrations of the end of the upper part relative to the lower part. A layer of the heated welded material is formed, localized by thickness, in which predominant absorption of the ultrasonic vibrations occurs, which allows one to obtain high-quality and durable welded joints without significant deformation due to the concentration of thermal energy in the welding zone. The effect of independent welding pressure on the strength of the welded joint of polycarbonate is considered. A new method of ultrasonic welding under the conditions of independent pressure is proposed. The method consists of dividing the static welding pressure into two components: the pressure of the acoustic contact in the zone of contact of the waveguide with the product, and the welding pressure that compresses the welded products, with the latter component being lower than the former. In order to obtain high-quality welded joints made of polycarbonate and to prevent displacement of the welded edges during the welding process relative to each other, a special preparation of the welded edges is developed, which allows one part to be moved vertically relative to the other during the welding process. It is established that the quality of welding depends on the speed of movement and the angle of cutting the edges.

This work examines a method of ultrasonic pressing of metal parts into a thermoplastic part using thermoplastic rivets and screws installed into the threaded holes obtained by ultrasound forming, welding metal parts through a pre-applied plastic layer, and welding metal and plastic parts through an intermediate plastic insert. It is shown that the introduction of metal fittings into plastic products using ultrasound is a progressive method of obtaining permanent joints of products from plastics and metals. It leads to an increase in labor productivity and ensures production of consistently high-quality and durable connections. The dependence of the holding force of the metal reinforcement in thermoplastic on the tightness is determined. The possibility of obtaining a metal-plastic welded joint using ultrasound is established. It was previously impossible to obtain such joints using classical methods of welding due to specific features of the metal-plastic material. The main technological modes of joining metal materials with thermoplastics are determined, namely static force, duration of ultrasonic action, waveguide oscillation amplitude.

In this work, the impact of dyes and fillers on the process of heat generation during ultrasonic welding of plastics was studied, which made it possible to influence the weldability and quality of products. Experiments to weld samples of plastics with various concentrations of dyes and fillers were carried out. Based on the experimental data, it was established that the main parameters of the welding process and the properties of the polymer influenced weldability and performance indicators of the weld joint. The nature and the concentration of the dyes and fillers injected into the polymer to obtain certain characteristics and colors had an impact as well. Optimal concentrations that provided the best weldability, strength and quality of the weld products were obtained for fat-soluble dyes and organic pigments (0.1–1.5 g/kg) as well as disperse fillers and inorganic pigments (5–12 g/kg). Types of dyes and fillers and their optimal concentrations for fat-soluble dyes, organic pigments and disperse fillers were determined. Parameters of the process of ultrasonic welding of dyed and filled plastics were defined. It was established that welded products with the recommended optimal concentration and types of dyes and fillers showed the best weldability, increased strength and performance, and could be used longer under various climatic conditions.

The report discusses the problems of formation of the collection of Russian anthroponyms, mythonyms, and theonyms in Russian panegyric poetry of the 18th century. Such a collection may serve as the basis for the compiling of a new dictionary of proper names in 18th-century Russian poetry, the main task of which will be the reflection of the transformation and development of the semantics of the “literary” anthroponym, the process of mythological anthroponyms and the onyms adaptation in the Russian culture.

This article briefly describes basic elements of machines for ultrasonic welding of plastics and the main materials used for manufacturing elements of ultrasonic waveguide oscillatory systems. A relationship between the amplitude of fluctuations of the welded material and a ratio of wave resistance of the product material and the waveguide tool geometry is examined. It is shown that when welding plastic products of a large thickness, it is practical to use waveguides made from aluminum alloys with a working end face with a diameter of 15 mm. It is established that the closer the acoustic characteristics of the waveguide material and the plastic are, the fuller the transfer of ultrasonic energy is when transiting through the interface of the welded polymeric materials. To assess the distribution of amplitudes of fluctuations in the welded material it is more convenient to use a transmission ratio, which decreases with a decrease in the wave resistance. It is established that the sizes of the working end face of the waveguide are most often defined by the properties, dimensions and geometry of the welded product. The application of the developed recommendations to the choice of material and sizes of the working end face of the waveguide can increase technological reliability of the ultrasonic welding process and improve quality of products.

A technique and a tool for ultrasonic welding by pressing a connecting element into a constant gap is proposed. The welded joints of plates arranged parallel to each other prove to be consistent in terms of strength and transparency. It is established that the coefficient of concentration of energy released per unit of volume of the parts being welded greatly depends on the contact area between them. When designing a welded seam, it is necessary to ensure edge preparation to reduce the contact area between the welded parts. In the case of a V-shaped protrusion in the design, the angle at its top should be approaching 90. The optimal technological parameters for ultrasonic welding by pressing into a constant gap are determined.

In this work, possible methods of ultrasonic welding of synthetic fabrics are considered and analyzed. Technological features of ultrasonic seam welding of synthetic fabrics are described. The key parameters of this type of welding that significantly influence the speed of achieving the maximum temperature in the fabric welding zone are identified. These parameters determine the intensity of the fabrics’ warm-up, and therefore, the efficiency of the welding process. Thermal processes occurring at seam welding of synthetic fabrics are studied. It is established that the welding time increases with an increase in the number of connecting layers as well as with addition of cotton to the fabric composition. It is determined that when welding synthetic fabrics of small thickness, heat removal to the waveguide and the support roller has virtually no influence on the maximum temperature at the border of the mating surfaces and on the time of achieving the maximum temperature. Experiments on welding lavsan, kapron and polypropylene fabrics are conducted. The dependence of the statistic welding pressure on the welding speed and the fixed gap between the waveguide and the support roller is investigated. It is determined that the movement of material under the waveguide doesn not have a warming-up impact on the neighbouring areas of the welded seam. The strength of the welded joints practically does not depend on the height and shape of the support roller.

An ultrasonic welding method for round-shaped products made from ABS plastic is described in this paper. This method can eliminate roughness and waviness on the contact surface between the planimetric waveguide and the welded part, increase heat removal from the surface of the welded part in the subwaveguide zone and improve the efficiency of ultrasonic welding as well as the strength and quality of the welded joint. It is shown that a mushroom-shaped waveguide is the optimal choice for planimetric ultrasonic welding of ABS parts of the fan wheel type with regard to the uniformity of the oscillation amplitude distribution along the perimeter of the waveguide’s working end face. The optimal form of the waveguide’s working end face is defined that entails fixing the connecting parts relative to the waveguide’s axis along their diameter. It is established that at a certain combination of the ultrasonic welding modes for ABS plastic the rate of deformation at large welding pressures can turn out to be higher than at small pressures. This is caused by the competition of three factors: temperatures, static welding pressure and concentration of energy on the welded surfaces. It is determined that for welding ABS plastic the so-called soft modes of ultrasonic welding with small static welding pressure and oscillation amplitude of the waveguide’s end face should be used. In this case welding occurs only due to the distribution of microroughness, without dents from the waveguide on the surface of the welded material. Optimal welding parameters for ABS plastic are determined.

The specifics of ultrasonic planimetric welding of polyethylene containers of irregular shape filled with foodstuff are considered in this work. A planimetric wave guide that can be used for welding polyethylene containers of a large diameter (up to 120 mm) and thickness ranging from 0.4 to 1.5 mm is proposed and implemented. The issue of obtaining high-quality leak-tight weld joints with stable mechanical properties on the surface of a polyethylene container exposed to corrosive environment is resolved. Various shapes of the working surface of the planimetric wave guide are developed, making it possible to weld containers with good appearance, durability and leak-tightness. A scheme for welding containers by a planimetric wave guide with an acoustic screen is proposed. The results of studies to determine the optimal parameters for the modes of ultrasonic planimetric welding are presented. The shape, material and position of the support in relation to the planimetric wave guide are defined. The technology and equipment for ultrasonic planimetric welding of polyethylene cans of a large diameter filled with various substances and foodstuff are developed. As the result of the research, all the studied liquids are divided into three groups depending on their influence on weldability.

Infections of urinary tracts (IUT) occupy a priority place both in the level of their outspread and the emergence of recurrences of the disease in ambulatory and stationary practice of a doctor; they are conditioned by inflammatory process, mostly of bacterial genesis, developed in different anatomic parts of urinary system – from fascia renalis to external urethral opening and often combined with pelvic inflammatory diseases. Purpose of research: to evaluate the effectiveness of complex therapy of chronic recidivating cystitis in combination with pelvic inflammatory diseases in women of reproductive age. Materials and Methods. A complex clinical and microbiological examination of 39 women aged from 18 to 39 having chronic reccurent cystitis in combination with pelvic inflammatory diseases in the observation dynamics (before and after the course of anti-inflammatory therapy with the inclusion of Tiflox and probiotic Lactovit Forte) was carried out. Results. As a result of the carried out research the symptomatic development of chronic reccurent cystitis at the background of latent development of pelvic inflammatory diseases was established. In the etiological spectre of chronic reccurent cystitis there were more often microorganisms (mostly E.coli – 82.1%) in the monoculture of critical and high number of microbs, and in 17 (43.5%) mixt-infection was established. Concordance when establishing Chlamydia (7.7%), Mycoplasmas (5.1%), Ureaplasmas (10.3%), Candida (33.4%), and Gardnerella vaginalis (10.3%) both in the biomaterial from urethra and genitals in comparison with the spectre of clinical characteristics certified the presence of interconnection of urinary and reproductive systems, which has to be considered when conducting complex anti-inflammatory therapy. Conclusion. Treatment of chronic reccurent cystitis should be conducted considering the heaviness and level of changes in the inflammatory process both from the side of urinary and reproductive systems in a single context. Only after the clinical analysis of all factors in combination it is possible to determine the tactics of treatment of infections of urinary system in women of reproductive age with the prescription of grounded and adequate therapy. Key words: infections of lower urinary tracts, pelvic inflammatory diseases, women of reproductive age, diagnostics, treatment of acute and chronic recurrent cystitis, Tiflox, Lactovit Forte.

Ложная аневризма подключичной артерии представляет собой чрезвычайно редкую сосудистую патологию. Истинная ее частота, особенно после коррекции врожденных пороков сердца у детей, неизвестна, хотя отдельные наблюдения встречаются в литературе. Патология может протекать бессимптомно, однако по мере увеличения размеров аневризмы клиническая картина наиболее часто манифестирует кровохарканьем, симптомами сдавления сосудов, нервов и/или дыхательных путей, тромбоэмболией, внезапной смертью на фоне разрыва и кровотечения. Изучение жалоб и данных анамнеза во всех случаях имеет большое значение для постановки диагноза. В большинстве наблюдений рентгенография легких может дать исчерпывающую информацию. Однако наиболее информативным и одновременно малоинвазивным методом диагностики ложной аневризмы подключичной артерии является компьютерная томография с внутривенным контрастированием. В данном сообщении представлены этапы диагностики и последующего успешного хирургического устранения ложной аневризмы правой подключичной артерии у ребенка раннего возраста после этапной коррекции сложного врожденного порока сердца.

Частота встречаемости сосудистых колец составляет 0,51 от всех врожденных пороков сердца. Одной из разновидностей сосудистых колец является сочетание правой дуги аорты с аберрантной (ретроэзофагеальной) левой подключичной артерией. Наиболее часто патология манифестирует дыхательными нарушениями (кашель) и дисфагией вследствие компрессии трахеи и/или пищевода аномально расположенными сосудами. Длительное существование указанных жалоб у ребенка является показанием к его тщательному обследованию. В диагностическом поиске ценную информацию могут предоставить рентгенологическое исследование и эхокардиография. Однако наиболее информативным методом диагностики оказывается компьютерная томография с внутривенным контрастированием. В данном сообщении представлены этапы диагностики и последующего успешного хирургического лечения полного сосудистого кольца у маленького ребенка с правой дугой аорты и аберрантной левой подключичной артерией.

Введение. Исследование заключалось в морфометрии легочного клапана человека с детальным изучением его геометрии. Цель: получить новые знания и обсудить возможность их применения в сердечно-сосудистой хирургии. Материал и методы. Морфометрия клапана легочной артерии проводилась в двух независимых группах: в 1-й группе методом аутопсии нефиксированных сердец, во 2-й методом прижизненных измерений на основании данных компьютерной томографии с внутривенным введением контрастного препарата. Результаты. В обеих группах получены сопоставимые результаты. Установлено, что геометрия здорового клапана легочной артерии имеет пропорцию золотого сечения, при которой отношение суммы диаметра (d) и высоты (h) клапана к его диаметру равно отношению диаметра к высоте и стремится к постоянному значению числа Фибоначчи (1,618). Аналогичная закономерность обнаружена для ширины створки (l) ивысоты клапана. Зависимость частей пропорции имеет сильную связь и нелинейный характер. На основании полученных данных разработаны и запатентованы формулы лекал для изготовления медицинских изделий с искусственным легочным клапаном (hd/1,618 lh1,618). Заключение. Морфометрия клапана легочной артерии может быть выполнена прижизненно с помощью метода компьютерной томографии. Геометрия легочного клапана содержит пропорции золотого сечения. Новые знания могут быть востребованы сердечно-сосудистыми хирургами при выполнении реконструктивных операций на выводном отделе правого желудочка, врачамирентгенологами и разработчиками медицинских изделий для сердечно-сосудистой хирургии.

Using the bilateral asymptotic method, a semi-analytical solution of a dual integral equation with its right-hand side in the form of a Fourier series is constructed. This equation arises in the solution of a number of contact problems of elasticity theory for bodies with inhomogeneous coatings. The efficiency of the method is illustrated in the example of the solution of the plane contact problem on bending of a beam lying on a functionally graded strip with arbitrary variation of the elastic moduli with depth. It is assumed that the strip is perfectly bonded to an elastic half-plane. Numerical results are presented for a strip whose Young's modulus varies harmonically with depth. In this case, Young's modulus of the substrate is 100 times greater than at the lower boundary of the coating.

Продемонстровані онкологічні результати радикальної простатектомії у 106 хворих клінічно місцево-поширеним раком передміхурової залози. Середній вік хворих на момент операції склав 62,1 (40-78) років, середній рівень ПСА - 29,4 (2,5-150) нг / мл. При патоморфологічної дослідженні у 17,9% виявлено локалізований РПЖ, у 19,8% - метастази в регіонарні лімфатичні вузли. Показник Глисона в операційному матеріалі Ј 6 був у 32 (30,2%), 7 - у 47 (44,3%), и 8 - у 27 (25,5%) хворих. Позитивний хірургічний край виявлено у 37 (34,9%), періневральная інвазія пухлини - у 52 (49,1%) хворих. Середній час спостереження склало 50,6 (12-129) міс. 5-річна безрецидивної виживаність склала 47,7%, 5-річна канцерспеціфіческая і загальна виживаність - 85,8%.

A semi-analytical solution of the contact problem of the indentation of a conical punch into a half-space with a coating inhomogeneous in depth is obtained. Young's modulus and Poisson's ratio in the coating very arbitrarily with depth. The solution is asymptotically exact for large and small values of the geometrical parameter of the problem (the ratio of the coating thickness to the radius of the contact area). Numerical values of the contact stresses are constructed using the example of a linear variation of Young's modulus in the coating.

A technology of ultrasound seam welding of polyethylene terephthalate films has been developed and ultrasound welding equipment and waveguides with spherical working ends constructed. The amplitude–frequency characteristics of acoustic systems are analysed. The dependence of the strength of welded joints on frequency, welding pressure, welding speed and the amplitude of ultrasound oscillations is determined.

Mathematical model of micro-heterogeneous medium with voids and shrinkage porosity is considered. Green’s tensor is used to obtain the formulas for macro modules of elasticity. Discrete and continuous probability distributions are used to describe random properties of microstructure elements. Convergence of the method is discussed. Sample calculations are provided.

The coincidence cross section and polarization have been measured for the proton-deuteron break-up reaction pD→ppn at 1 GeV in a kinematically complete experiment. Two final protons from the reaction were detected in coincidence by means of a two-arm spectrometer at non-symmetric scattering angles θ 1 =19°–27°, θ 2 =61° in the momentum range of the neutron-spectator up to 0.3 GeV/ c . At kinematic conditions of the experiment the coincidence cross section is well described in the framework of the single scattering impulse approximation with the Paris wave function of the deuteron. The polarization is also in good agreement with IA predictions.

We present a new explosion-proof construction for a waste heat boiler with an extended working life, guaranteeing fixed advantages at the expense of the dual-circuit structure of the heat conducting system, using closed two-phase thermosiphons in the primary circuit, in contact with the heated gas flow. We set forth the methodological bases for the design and our experience of industrial application of manufactured units of this type.

EI SEP PHASE ACC; The paper describes the spectrometric system “SPES4–$\pi$” used at the National Laboratory Saturne (CE Saclay, France) for the exclusive study of the baryon resonance excitation in inelastic α and d scattering on the proton, as well as coherent pion production in charge exchange reactions. The system consists of the magnetic spectrometer SPES4 and two wide-aperture position-sensitive detector arrays, equipped with wire chambers and scintillator hodoscopes, installed around a large-gap C-shape dipole magnet.

This is a brief description of the forward spectrometer which was used as a part of SPES4π installation for an exclusive investigation of the p(α,α 1)X and p(→ d,d 1)X reactions at the SATURNE-II accelerator (CE Saclay). The spectrometer was designed to register the products of the recoil particle decay and to select the specific channels of the reaction. It consists of a set of multiwire drift chambers and scintillation counter hodoscope and was especially adapted for the operation close to a high intensity direct beam of the accelerated particles. The main parameters of the spectrometer and the results of its test are presented.

The feasibility of thermosiphon cooling system used in energotechnological units of non-ferrous metallurgy is proved. Future design prospects of thermosiphons and recommendations on determination of their parameters are given. Structural composition of the thermosiphon cooling system and the results of its operation in the industrial-scale test unit of KIVCET (oxygen-flash-cyclone electrothermal) smelting plant are described.

A detector system for measurement of angular correlations in binary fission reactions, which are induced by 1 GeV protons, is described. A new type of parallel plate avalanche counsisting of two grids delivers the start signal for the time-of-flight measurement for the correlated fragments. With this detector we obtained an energy loss of 7.8 MeV and an intrinsic time resolution of τ=320 ps for spontaneous fission fragments from a 252Cf source. A large area position-sensitive parallel plate avalanche counter (3.5×18 cm2) with delay-line read-out measures the coordinate of the complementary fragment within an accuracy of 4.3 mm (corresponding to 1.3°). The spatial resolution has been measured for α-particles and fission fragments under different conditions. The reliability of the developed detector system was checked experimentally with U and Bi targets, which were bombarded with 1 GeV protons.

The polarization has been measured in the elastic scattering of 1 GeV protons on 12 C. The measurements have been performed by the double-scattering method using a magnetic spectrometer with an energy resolution of 2.5 MeV. The data obtained are fitted with the Glauber model.

Typical regions of development of the process of heat carrier phases interaction are studied experimentally and their boundaries in the closed two-phase counter-current flow system are determined. The influence of the two-phase medium compressible effects on the stability of the wave flow of the liquid film in the counter-current flow with the vapour flow is established. It is shown that the heat transfer limits in two-phase thermosiphons are determined by the conditions of counteraction of the heat carrier phases along the axis of the apparatus.