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Polycrystalline hypoeutectoid aluminum bronze was fabricated by melting of pure metals technique in an induction furnace. Cu-Al-Ni alloy was investigated in cast state and after hot extrusion. Moreover, thermomechanical treatments was conducted via torsion tests between room temperature and 9000C. The research focused to investigate the factors influencing the deformation behaviour, mechanical properties and microstructural evolution of a Cu-Al-Ni alloy. Mechanical characterization showed that upon extrusion and t...

Implementation of the development program for the Northern and Arctic territories is not possible without the use of modern materials and technologies in the construction industry. One of the most common and popular building materials is the fine grained concrete, for the production of which, use chemical additives, mainly imported, improving the performance characteristics of the composite. Therefore, the actual problem is the replacement of imported components with Russian-made additives. As such an additive, te...

Amiodarone (AMD) is an antiarrhythmic agent used for the treatment of ventricular arrhythmias, arterial fibrillation, and severe rhythm disorders. The main therapeutic disadvantage of AMD is its low oral bioavailability and low water solubility. The aim of the study was to obtain the hydroxylpropyl-?-cyclodextrin/AMD inclusion complex and to assess its degree of drug loading using a new HPLC method. The solubilizing effect of cyclodextrin on AMD was evaluated by the phase solubility method. The concentration of AM...

The current stage in the development of the construction industry is associated with improving the consumer properties of composite materials, increasing their operational efficiency, increasing production volumes and service lives. One of the ways to solve the problem associated with increasing the durability and reliability of materials from plant raw materials is to create compositions based on the synthesis of ceramic materials with an ordered structure by mineralization of the wood matrix with sol-gel surface...

The structure and phase composition of annealed and irradiated beryllium plates were studied by X-ray analysis. Durable X-ray irradiation leads to phase transition of a normal hexagonal beryllium lattice into a beryllium superlattice. This superlattice is composed of beryllium superatoms that form a face-centered cubic lattice with the lattice parameter of 6.2205 ? and a superatom core that crystalizes into a diamond-type lattice with the lattice parameter of 1.5703?. It is shown that beryllium has three phase sta...

In this paper, combined effects of carbon fibres treatment and compatibilizer polymers (PE-g-MA) on the structure and properties of PA/PE/PE-g-MA/ functionalized carbon fibres composites were studied. The optimum formulation was used to prepare a series of nanocomposites under different technological conditions. Also, a correlation between their physico-mechanical properties and IR spectra (ATR technique) was proposed. The carbon fibres functionalisation consisted in oxidizing the nanoparticles with oxidant mixtur...

On the base of unsaturated polyester resin and nano powder fillers, polymer concrete (PC) was produced applicative in aggressive underground conditions. The curing agents of the resin for the polyester resin were Akcobalt 6% (cobalt 2-ethylhexanoate mixture) and Akperox A1 (Methyl Ethyl Ketone Peroxide-MEKP). Ultrafine powder was produced by grinding of a coarse mixture on the PULVERISETTE 7 premium Line planetary mill by a dry method. Selection and designation of concentrations of aggressive media - sodium sulfat...

Pigments of the inhibitory type are the active principle of most primers used to protect metals from corrosion. Developers of anticorrosive paint and varnish materials seek to replace chromium-containing pigments, which widely used until recently due to their toxicity, with more environmentally appropriate choices. These include ferrite pigments. It is known, that the most spread method for the synthesis of ferrites, which are complex oxides or salts of ferrous acid, is the joint calcination of iron oxides with ox...

The reinforcement of ceramic composites with the help of carbon nanotubes (CNTs) is used to increase and stabilize the mechanical properties of composites based on silicon carbide, such as strength, fracture toughness and modulus of elasticity. To save the properties and reduce the synthesis temperature of ceramics based on silicon carbide, an aluminum-magnesian spinel is introduced into the matrix. A nanocomposite with a matrix of silicon carbide (SiC) and spinel (MgAl2O4) and with a CNT content of 1-3% by weight...

At the present time, the widespread introduction of cost-effective production of a method for processing pressure in the solid phase of polymeric materials is hampered by the fact that despite the possibility of improving the strength and a number of technological characteristics of materials, high residual orientational stresses are created in the products, which over time (or when heated), lead to a change in the geometric shape and dimensions of the product. In this connection, it is promising to use the stage ...

The polymers performance in membrane technology provide a stable and very high level of pollutant removal. The selection capacity and low cost of the polymeric membrane technology are important factors in wastewater treatment applications. Four membranes from polysulfone with different concentration blend in N-Methyl-2- pyrrolidone were obtained by phase inversion method in our laboratory. The membrane performances were characterized by flux rejection, relative flux, retention capacity and morphology. The surface ...

Particle boards are increasingly being used as a structural material. The quality of the wood from which they are made, has been steadily declining. This provides the means for tackling possible ways of particle board mechanical properties preservation and improvement. The methods and results of experimental investigation on the additive influence of shungite nanopowder whenmixed in the glue for one-ply particle board are presented in the article. Wooden particles of coniferous and hardwood species as well as glue...

For a balanced life, milk and dairy products occupy an important place in the gastronomic culture of each country and are highly appreciate for their nutritional values. Cheese, as the most consumed milk ? derived product, it turned out to be a food product rich in nutrients that was the subject of numerous studies because of its contribution to nutrition and health. There are a very large number of cheese types,with different composition, due to many variations in production process, and that's why it is difficul...

Increasing tendency for fresh food - fruits, vegetables, and herbs - consumption worldwide and also in our country shows the important role they play in the diet. In this case, it is not only good looks, nice color or taste and aromas that are considered to be important, but especially their nutritional value, rich in sugars, vitamins and minerals necessary in the diet of the human body. They also have the advantage to be fit for consumption without any processing which could reduce their nutritional value. The pu...

Membrane technology is a separation process used predominantly in the primary and secondary sectors of industry, being a viable option over conventional water and wastewater treatment systems. Due to fresh water scarcity increment at global scale, it is essential to develop a best available technology to reduce the negative effects of water contamination and to produce potable and process water, also. Pressure driven membranes have drawn high attention in the past 60 years, due to simple operability and maintenanc...

The unique properties of aerogels make them promising materials for use in various industries. The production lines, which are currently organized by foreign companies, are aimed at obtaining exclusively monoliths and blankets of aerogels of certain sizes. However, for many potential applications, forms other than monoliths, namely particles, are required. In many works, the prospects and relevance of the use of organic aerogel particles for pharmaceuticals (drug delivery systems), medicine (medical products), foo...

Due to its properties, lightweight, strength and corrosion resistance aluminum and its alloys are chosen for building various industrial equipments that are used in different specific environments. Aluminum and its alloys cannot escape from corrosion and it requires a proper handling. Aluminum and its alloys will corrode very quickly after cleaning so any treatment must be swift to prevent corrosion becoming trapped under the base coating layers. Aluminum corrodes almost immediately forming an oxide layer that wil...

When metal structures are manufactured, the heat cycle introduced by the applied welding technology can cause structural changes in the base material, as well as residual stresses, which under certain circumstances can lead to changes in the shape of the structure. This paper analyses certain possibilities to avoid and reduce the stress level and the distortions in the welded structure by applying various welding technological methods. The paper presents the results obtained after the fillet welds were made using ...

The welding characteristics of the welded joints are directly influenced by the thermal conditions applied during welding. At the same time, the welding type process influences the geometry of the welded seam, the nature and the extent of the structural transformations, the tensions and deformations level, as well as the values of the mechanical characteristics of the welded bead (yield strength, hardness, toughness etc.) The paper presents the experimental procedure, the results and the conclusions on the influen...

The aim of the paper is determination of the temperature field which is caused by a heat flux in a thermosensitive (thermophysical parameters depending on temperature) layered medium which contains a foreign inclusion. The heat flux is concentrated at one of the boundary surfaces of the medium, the other boundary surface of which is thermally insulated. There exists ideal heat contact at the surfaces of the conjugated layers. In order to determine temperature regimes in such a medium, a nonlinear equation of heat ...

The drip feed reactor system for continuous biosynthesis of bacterial cellulose with desired microfibril orientation is proposed. Native bacterial cellulose is obtained on the glucose media using symbiotic complex of yeast and bacteria A.xylinum. Micromorphological characteristics of the bacterial cellulose structure are visualized using SEM Sigma VP ZEISS scanning electron microscopy. The crystallinity degree of the specimens is calculated by new method using X-ray diffractometry (XRD-7000S diffractometer). The 2...

Bisphenol A (C15H16O2) 2,2-(4,4?-dihydroxydiphenyl) propane (BPA) is known for its endocrine disrupting properties in human body in addition to various other harmful effects. BPA has been detected in the aquatic environment at concentration levels varying from nanograms to micrograms per litre of water in many countries and regions. Due to the inefficiency of BPA removal using the common water treatment methods (physicochemical, biological, and electrochemical), advanced oxidation process was applied. UV-VIS photo...

Low-cost sensors, either electrochemical, optical or light scatter based and piezoelectric, due to low price and performance explainability are becoming more available for monitoring, studying and explaining urban air quality. This paper explores low-cost sensor technology applicability for air quality measurements in urban territory. At least two month long monitoring campaigns were conducted during summer 2018 in Riga (Latvia). For validation purposes different monitoring sites were selected in order to assess i...