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The paper discusses the results of saponite research from the Tashkiv deposit of Ukraine. X-ray structural analysis proved the necessity of preliminary cleaning of saponites from mineral impurities. The study of the morphology, nanoprofile and topography of the surface of saponite by the methods of SEM-microscopy and Atomic Force Microscopy revealed that the mineral is represented by aggregates of nano- and microparticles of a pyramidal shape. Its characteristic feature is the heterogeneity of isomorphic substitutions of ions in the tetrahedral and octahedral sheets of the structural elementary package. According to X-ray fluorescence analysis, saponite contains a significant amount of Fe3+, which isomorphically replaces magnesium Mg2+ and, accordingly, is located mastly in the octahedral sheet of the structural package with a charge from +0.37 to +0.35. The number and mechanism of isomorphic substitutions determine the presence of a total negative charge of the crystal lattice (from –0.38 to –0.3), the value of which ensures intensive interaction with water molecules of the interpacket space with the formation of surface OH groups. Accordingly, both acidic and alkaline Lewis and Brønsted centers are present on the surface with a predominance of acidic ones, so the acidity function is 5.82, and the point of zero proton charge is pH = 5.5. During dispersion in water, a part of the alkaline centers of the side surface are transformed into Brønsted acid centers as a result of their protonation, which causes an increase in the pH of the dispersion medium to pH = 8–8.6. Accordingly, the isoionic state is reached at pH = 7.5. The difference in pH values characterizing the isoionic state of the surface and the point of zero net proton charge (PZNPC) indicates the presence of weak acid-alkaline centers on the surface. The study of the adsorption of acid-alkaline dyes showed the adsorption of alkaline (pK = 1/3) and acid (pK = 7/14) dyes on saponites. The latter is significantly reduced due to the preliminary hydration of the solid surface - mainly the lateral edges of the particles. Acidic dyes are not adsorbed from a dispersion medium with pH < 5.5 (PZNPC), and basic dyes are adsorbed at pH > 5,5( PZNPC). [ABSTRACT FROM AUTHOR]

The paper considers the peculiarities of damage to welded joints of steam pipelines that have been operated for a long time (more than 280 thousand hours) under creep and fatigue conditions. It is established that the damage caused by creep and fatigue depends to a large extent on the structural and phase state of the metal of welded joints, which changes considerably during their long-term operation. With longer service life of welded joints, a ferrite-carbide mixture forms in their structure as one of the components. The presence of such a mixture contributes to acceleration of damage of welded joints. The dependence of formation of the ferritecarbide mixture on the initial structure of welded joints was established, and recommendations were given for producing an initial structure with improved quality characteristics, which is advisable for increasing their reliability and service life. [ABSTRACT FROM AUTHOR]

This paper describes the method of shaping the product using 3D technology by means of applying arc heating and consumable material – a wire with a diameter of 1.2 mm. The aim of the work is to study the structure and mechanical properties of the product manufactured using additive 3D technology. Each deposited layer consists of three separate beads: two lateral ones, which provide the set contours of the layer, and one middle one, which fills the space between the two lateral ones. Electric arc surfacing was carried out with the help of a welding robot. The use of a robot made it possible to control the time between layer depositions, thereby controlling grain growth. Also, the use of a robot makes it possible to reproduce a set part as accurately as possible according to a pre-calculated and designed model with a minimum error of repetition of the torch movement of ±0.03 mm. As a result, the structure and mechanical properties of the deposited product were investigated. It is shown that the product manufactured according to the presented technology has a fine-grained ferrite-pearlite structure; the grain size ranges from 7 to 10 numbers. The mechanical properties along and across the deposited layers were studied. The indices practically do not differ. A comparison of their values with normative ones showed that they exceeded normative values by 10–50%. 14 Ref., 3 Tabl., 4 Fig. [ABSTRACT FROM AUTHOR]

The paper presents the results of investigations of the strength, hardness and structure of butt joints on aluminium alloys of different alloying systems, produced by friction stir welding (FSW). It is shown that this process allows producing sound joints of aluminium alloys of different alloying systems, both in similar and dissimilar combinations. This is true not only for aluminium alloys made by casting by the standard technological scheme, but also for granulated alloys, containing the oversaturated solid solution of refractory transition metals, produced by powder metallurgy. It is found that the strength of welded joints produced at FSW of aluminium alloys, depends on the chemical compositions and mechanical properties of these alloys. Maximum ultimate strength is demonstrated by welded joints of the following high-strength alloys: 1995 (483 MPa), 1963 (473 MPa) and D16 (441 MPa), which is due to a slight degree of metal softening in the zone of thermomechanical impact (ZTMI), which is where the samples fail at mechanical stretching. Destruction of samples of welded joints of dissimilar aluminium alloys also runs in this zone or on its boundary with the heat-affected zone (HAZ) from the side of the softer alloy. Their ultimate strength is on the level of the joints of the respective similar alloys. It is shown that intensive plastic deformation of metal at FSW of dissimilar aluminium alloys results in formation of grains of practically globular shape in the weld nugget in the permanent joint zone, their size not exceeding 4 – 6 μm. In granulated alloy welding, the oversaturated solid solution is preserved in the granules, just their mechanical refinement takes place, resulting in a fine dense structure of the weld nugget, and the granules containing an oversaturated solid solution of refractory transition metals are uniformly distributed over the entire volume of the matrix in the weld metal. [ABSTRACT FROM AUTHOR]

The paper gives the results of investigation of the features of formation of D16 aluminium alloy welds in consumable electrode welding with application of two insulated fi ller wires or embedded elements of diff erent chemical composition. Wires of Zv1201, ZvАК5, ZvАК12 grades of 1.6 mm diameter and embedded elements cut out of V92, V96 and 7056 alloy blanks with diff erent content of zinc were evaluated. It is shown that ZvАК5 wire ensures reduction of the length of solidifi cation cracks and quantity of pores in welded joints, and welded joint strength becomes higher at addition of zinc into the welds. 15 Ref., 5 Tabl., 5 Fig. [ABSTRACT FROM AUTHOR]

The paper presents a review of studies on the influence of inoculation of dispersed refractory compounds into the weld pool on formation of weld metal microstructure in low-alloyed high-strength steels. Features of the process of primary structure formation are considered in the presence of refractory nonmetallic inclusions in the liquid metal, as well as on the interface of δ-dendrites and γ-phase. Possibilities of inoculant influence on the temperature range of bainite transformations, possibilities of formation of microstructural components with higher brittle fracture resistance, and improvement of weld metal toughness values are shown. 18 Ref., 5 Fig. [ABSTRACT FROM AUTHOR]

In recent years, Ukraine has been Increasing the import of agri-food products at a rate that signfiicantly exceeds the rate of increase іп exports. As a result, the Import-export coverage ratio is decreasing, and for many commodity groups and commodity items, instead of a positive trade baiance, a negative one appears. This article is devoted to the study of the formation of volume, dynamics, structure and reasons for the increase in the cost of imports based on the use of inethods and techniques of economic and statistical analysis. The paper states that the main reason for the increase in the volume and value of imports is the disproportion between the Iow growth rates of domestic production of agricultural and food industry products and the high growth rates of household incomes. The Iatter circumstance contributes to the formation of a constantly growing demand and a shortage of goods for individual commodity items, which is covered by an increase іп imports. The analysis of the commodity and geographic structures of imports of goods of four product sections was carried out in accordance with UKTVED. It has been estaЫished that for a number of commodity groups and commodity items of the first, second and fourth sections, imports increase for such types of products for the production of which Ukraine has the necessary conditions (Iivestock products, vegetaЫes, fruits, berries, seeds of cereals and oilseeds, most of the commodity food groups). Increasing the production of these types of products can significantly reduce their imports. For products of other commodity groups and commodity items in Ukraine, there are no necessary conditions (tropical crops, fish and crustaceans, etc.) and the cost of imports is determined by the financial capabilities of importers. The study of the geographicaI structure shows that the main exporters of agri-food products to Ukraine are the countriea of the European Union, which fully use the conditions of the free trade zone with Ukraine and are the main suppliers of products of the first and fourth sections (products of animal origin, some prepared food ргоducts). It is for these types of goods that a significant negative ЬаІапсе is formed in trade with the EU соuntries. . It has аІао been estaЫished that imports from other regiona of the world take pIace mainly for thoae types of products that are not produced in Ukraine. The conclusions provide recommendations that relate to the possibilities of reducing imports, mainly Ьу increasing domestic production, without excluding the use of administrative regulation for certain types of goods. [ABSTRACT FROM AUTHOR]

The paper presents the results of studying the features of weld formation at consumable electrode pulsed-arc welding of 4 mm AMg5M alloy in diff erent positions at the speed of 23 m/h. with forming backing element (FBE) and without it. It is shown that sound welds form irrespective of the angle of butt joint inclination relative to the horizontal plane. FBE presence increases the geometrical dimensions of weld made with consumable electrode by 4 – 12% on average, depending on the position of butt joints. Obtained data clearly demonstrates the possibility of achieving the required quality of welds and high level of mechanical properties in consumable electrode welding of aluminium-magnesium alloys at diff erent positions of the butt joints without FBE application. 6 Ref., 3 Tabl., 4 Fig. [ABSTRACT FROM AUTHOR]

The paper presents the results of comparative studies of corrosion-mechanical resistance of welded joints of V1341 alloy 1.2 mm thick, produced by manual argon-arc welding with free and constricted arc, after different types of heat treatment (HT) – artificial aging and full cycle heat treatment (hardening and artificial aging). It was shown that artificial aging increases the strength characteristics of welded joints: those produced by free arc - by ~23%, compared to the base metal, by constricted arc – by ~29%, but reduces the relative elongation by ~82% and ~84%, and the strength coefficient – to 0.77 and 0.71 (0.81 and 0.83 in as-welded state), respectively. The full cycle of HT provides increase in both strength and ductility. After artificial aging, as well as after a complete heat treatment cycle, the potential difference between the base metal and the HAZ does not exceed the permissible value of 0.05 V (according to GOST 9.005), which will not be dangerous at operation in non-aggressive environments. Artificial aging and full HT cycle do not impair the resistance of welded joints of VB1341T alloy to exfoliating corrosion compared to as-welded state, which is assessed as value 2. An increase of resistance to intercrystalline corrosion (ICC) after artificial aging was demonstrated, the maximum depth of which was 0.301 mm for the joint produced by a free arc, and 0.233 mm – for a joint produced by a constricted arc (in as-welded state it was 0.350 mm and 0.47 mm, respectively). After a complete HT cycle, the ICC depth was 0.287 mm and 0.345 mm, respectively. Artificial aging reduces the corrosion-mechanical resistance of welded joints produced by free and constricted arc: the time to fracture of the samples was 9 and 12 days, respectively (compared to 45 days in as-welded state), but after a full cycle of HT maximum time to fracture of welded joints increased to 54 and 31 days, respectively. Welded joints produced by a constricted arc had higher corrosion-mechanical resistance after a complete heat treatment cycle. [ABSTRACT FROM AUTHOR]

The paper presents the results of studies of corrosion and mechanical resistance of welded joints of V1341 alloy of 1.2 mm thickness, depending on the technology of manual argon arc welding with free and constricted arc. The strength coefficient of welded joints is 0.79 and 0.8, respectively. Potentiometric measurements showed an electrochemical heterogeneity between the base metal and welded joints obtained by free and constricted arc; with a potential difference equal to 100 mV and 86 mV, respectively. More positive potential is inherent to the region with a smaller weld area, which is safe for operation. Accelerated corrosion tests have determined that the shape of the arc column in manual welding does not affect the resistance of welded joints against exfoliating corrosion and against corrosion-mechanical breaking under conditions of constant deformation. The level of resistance of the base metal against exfoliating corrosion of the joints, produced by both types of arc welding technology, was estimated by number 2-3. The fracture time of specimens of the joints produced by free arc welding, decreased on average to 20 days compared to the base metal (73 days). Similar results were obtained for joints welded by a constricted arc. At the same time, it was found that using of a constricted arc for welding causes a lowering of the resistance of the joints against intergranular corrosion. The maximum breaking depth of grain boundaries for joints produced by a free arc is 0.350 mm, and for the joints made by a constricted arc it is 0.460 mm. [ABSTRACT FROM AUTHOR]

At present ample quantity publicated of papers on forming and physicochemical propetties of polyelectrolyte complexes free occurence on account of their considerable practical aplication. This polymer systems, as is well known, based on opposite charged polyelectrolytes. However structural organisation of polyelectrolyte complexes practically non vere investigated. At present ample quantity publicated of papers on forming and physicochemical propetties of polyelectrolyte complexes free occurence on account of their considerable practical aplication. This polymer systems, as is well known, based on opposite charged polyelectrolytes. However structural organisation of polyelectrolyte complexes practically non vere investigated. In this connexion, on this work structural organisation two type of polyelectrolyte complexes based on Na-salt of carboxymethyl celllulose and polyethyleneimine or hydrohlouride polyethyleneimine was investigated. Using weide- and small x-ray scattering two type polyelectrolyte complexes based on carboxymethylcellulose and cationic polyelectrolytes with differently ionic force was investigated. It was esteblished that sample polyelectrolyte complexes based weak ionic force cationic polyelectrolyte have amorphous structure whereas based on big ionic force cationic polyelectrolyte have amorphouse-crystalline structure. Was shown that all polyelectrolyte complexes have structure heterogeneity nanoscale type with distribution their region of heterogeneity chaotically on space. The polyelectrolyte complexes with big ionic force of cationic polyelectrolyte have area of heterogeneity bigger in comparison with similar polymer systems based on cationic polyelectrolyte with small ionic force. [ABSTRACT FROM AUTHOR]

The paper gives the results of studying the effect of various heat treatment operations on the structure and mechanical properties of the base metal and welded joints of sheet aluminium alloy of V1341 grade 1.2 mm thick, produced by manual nonconsumable electrode argon-arc welding. The dependence is established between the structural state of the metal of welded joints of this alloy on the kind of heat treatment that affects the level of strength and ductility. A significant effect of improvement of the structure and mechanical properties is achieved, when conducting complete heat treatment, which includes quenching and artificial ageing of the alloy and its joints. Compared to artificial ageing modes, this kind of heat treatment allows producing a stable metal structure, characterized by smaller dimensions of phase precipitates and inclusions, that promotes increase of the strength level, under the condition of preservation of the ductility values. [ABSTRACT FROM AUTHOR]

The paper presents the results of investigations of brazed joints of 08Yu galvanized steel, produced by welding, arc and plasma brazing. It is confirmed that in the first case, spattering of the liquid pool metal, zinc evaporation and porosity formation take place. The influence of energy input on brazed seam parameters was studied in plasma brazing with application of BrKMts 3-1 brazing filler metal. It was found that increase of energy input leads to reduction of face reinforcement height, but promotes increase of the reverse reinforcement height, that requires a greater amount of brazing filler metal. It was empirically determined that energy input value in the range of 520 - 590 J/cm ensures producing butt joints of galvanized 08Yu steel with optimum size of reverse reinforcement. X-ray microprobe analysis showed that high-quality dense welds form in this mode that have the structure of copper-based solid solution with dispersed inclusions of iron-based phase, enriched in silicon. 11 Ref., 1 Tabl., 9 Fig. [ABSTRACT FROM AUTHOR]

The paper presents the results of studying the weldability of sheet aluminium alloy of V134T grade of Al-Mg-Si-Cu-Fe system under the conditions of nonconsumable electrode manual argon-arc welding. This alloy is characterized by high susceptibility to hot cracking in welding. The hot brittleness index is equal to A = 65.8 – 85.5 %. The impact of filler material chemical composition on hot cracking resistance of weld metal was studied. It is found that in welding by batch-produced wires of SvAMg63, Sv1201, Sv1217 grades the crack resistance value is A = 30.3 – 53.9 %, and at application of wire of ZvAK5 grade this characteristic of welds is equal to A = 6.6 – 19.8 %. Nonconsumable electrode manual argon-arc welding of V1324T alloy allows producing tight sound joints of this material with strength coefficient of 0.80 – 0.87 which also depends on filler wire chemical composition. The value of ultimate strength of the alloy welded joints, made using different grades of filler wire is equal to σt = 193.2 – 209.0 MPa, and the yield limit σ0.2 = 138.4 – 151.6 MPa; relative elongation δ = 3.1 – 5.4 %, bend angle α – 40 – 65 deg. [ABSTRACT FROM AUTHOR]

The liberalization of the conditions for conducting foreign economic operations, in particular - the establishment of a free trade zone between Ukraine and the European Union (EU), upgraded the need to increase the competitiveness of Ukrainian commodity producers to the level of the EU member states. The main link in the chain of formation of commodity exports is the processing industry. Hence, the objective of the paper is to carry out a comparative assessment of key structural indicators of the processing industry of Ukraine and the EU member states in terms of production. According to the results of the set of indicators' calculations, it is established that Ukrainian processing industry is highly specialized, since its structure is dominated by two types of industries - food and metallurgy, which produce near 50% of the total output, gross value-added (GVA) and GVA of export of this type of industrial activity. Instead, in the EU- 28 in the output structure and GVA of the processing industry, the share of key productions (food and transport) is in total less than a third, and the gap between the largest and the smallest shares tends to decrease, while in Ukraine, by contrast, it is increasing. The basis of the commodity structure of exports in the EU-28 is the production of high-tech manufacturing (machines, computers, pharmaceuticals). Ukraine is generally inferior to the EU-28 in terms of the share of GVA in the production of the processing industry (excluding coke, other vehicles and textiles production). A comparative analysis of the GVA structure of Ukrainian and Polish processing industries has shown the need for its further improvement in Ukraine, in particular - in the direction of optimizing the taxation and subsidizing systems of the national industry. [ABSTRACT FROM AUTHOR]

This paper deals with studying of the influence of physical factors (UV-radiation, temperature, humidity) and microbial cultures (Yarrowia lipolytica, Bacillus subtilis, Pseudomonas fluorescens) on the structure of the segmented polyurethane (SPU) based on the oligobuthyleneglycoladipinate during its degradation. Method of pyrolysis mass spectrometry was used to analyze the processes. It was found, that the original SPU and SPU after UV irradiation have a two-stage character of their gas- discharge products, which confirms the presence of two blocks in the molecular structure of the SPU. Influence of physical factors on the SPU leads to changing of the thermogram profile, that is a result of destruction of the ester groups of oligoglycol component of SPU, decrease the number of hydrogen bonds at the interface between the hard domains with a flexible matrix, formed by the oligoester units, with simultaneous weakening of intermolecular interactions in the bulk of the two blocks. Investigations have shown that all cultures of microorganisms being used in the experiment, anyway affect on the SPU film, but Bacillus subtilis and Pseudomonas Fluorescens cultures are the most effective, obviously, due to their ability to consume nitrogen-containing (diisocyanate) component of the SPU. [ABSTRACT FROM AUTHOR]

The condition of the restaurant business in Ukraine has been studied, and this study showed that at present, many enterprises of the restaurant business cannot stand competition and close down in the context of crisis, high level of inflation, drop of income level of the population. However, the restaurant business is one of the most widespread types of small businesses both in Ukraine and in the world, so the basic directions of its improvement are specified in the article. It is proved that in spite of the large number of scientific papers and publications, the problematic issues of cost accounting at the enterprises of restaurant economy remain unsolved to the full extent. We investigated the role and place of distribution costs and production costs in the circulation of capital and defined their substantive content. It is proved that the activities and internal characteristics of any enterprise better reveal in the functions performed in it that requires a certain amount of time and resource expenses. Therefore, there is a direct link between the cost values for the realization of its common functions, size of the enterprise, features of its activity, sectoral affiliation, that answers the question about the sources of expenses. We suggested a functional and cost-based structure of restaurant business enterprises, recommended classification of expenditure of catering business enterprises, depending on the types of economic activity and enterprise management objectives, which is the basis for the introduction of functional reporting of expenses enterprises restaurant business and calculation of production costs at restaurant business enterprises, and which is also necessary for organization of managerial accounting. [ABSTRACT FROM AUTHOR]

Purpose. The paper analyzed the bionic principles of formation as the main components of the project activity. The concept of harmony form, its nature, depending on the tasks use bionic principles in shaping contemporary art modeling clothing collections. Methodology. In carrying out scientific work used modern methods of research, such as literary and analytical, systematic and structured, bionic and morphological analysis, the method of classification of structural features of tectonic building form. Findings. As a result of the research identified a number of objective factors that allow a maximum benefit and efficiency bioanalohy use in forming the subject environment, while maintaining the necessary balance and compositional integrity of nature. In work the principles of harmonious forms, colors and ornamentation models in modern collections of clothing designed based bioanalohiv. Originality. From a scientific point of view defines the principles of biological objects analysis revealed the main stages of the bionic morphological analysis and synthesis of modern forms of clothing with improved ergonomic and aesthetic properties. Practical value. The studies were used to create collections of contemporary women's clothing, with a distinct artistic and compositional properties, based on the selected creative source-bioanaloha. [ABSTRACT FROM AUTHOR]

The aim of the article. The aim of the article is justification of prospects of further innovative development of economies of three countries of the South Caucasus. The results of the analysis. After the collapse of the Soviet Union, the South Caucasus countries have found their place in the capitalist world economy as peripheral states. However, all three states in the region have their own economic structural features and differences, both in terms of their current situation and prospects in terms of economic development. In this paper, key features and prospects of economic development are analyzed and identified. In terms of economic prospects the opportunities and challenges of participation in the South Caucasus countries and the Eurasian Customs Unions are discussesed. In the last years the South Caucasian countries showed rather high rates of economic growth, but the level of economic development of their economy is low. Economic systems of those countries are characterized with a number of structural imbalances and problems. In Azerbaijan economic growth was provided at the expense of increase of oil's production and export. In Georgia and Armenia economic growth was provided at the expense of external financing that stimulated consumer demand, growth in building sector and in sectors of services. Nowadays economies of the South Caucasian countries have been practically exhausted opportunities of extensive growth. In Azerbaijan the oil boom will come to the end soon. In Armenia and Georgia quite high shortage level of the current account remains and both countries have rather big external debt. In the conditions of world economy growth deterioration, especially in Russia, volumes of foreign trade and streams of money transfers will be reduce. It will negatively affect the prospects of their economic growth. All countries of the region need some new markets and strategic investments. The Customs Union represents an attempt to make high-quality break in the integration direction. But the raw model of economy in Russia is an objective obstacle for integration of economies of the countries of region with it. Conclusions and directions of further researches. If in some ways membership in the Customs Union is favourable for Azerbaijan economy (with strong export and transit economy), it will cause damage to Georgian and Armenian economies which depend on import, for example higher tariffs will be put; countries will lose an autonomy in decision-making in questions of international trade. Participation in the Customs Union will lead to narrowing of prospects of the countries of the region in the European direction. And it can encourage the countries of region to closer integration with EU or with other semi-peripheral countries of Eurasia. [ABSTRACT FROM AUTHOR]