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Microstrip devices have found wide application in various fields of radio engineering. However, such devices are made on dielectric substrates from various materials - glass,mica, ceramics, etc. In the process of manufacturing microstrip devices, it is possible to use, as etching method, this removal of excess copper coating, and removal of copper coating with special equipment, for example a milling machine . As a result, at various stages of manufacturing, material waste remains in large quantities, a solution f...

Miniaturization of microwave devices, such as directional couplers, filters, switches, etc., is an important practical problem due to the trend of integration of portable and small high-frequency electronics. In this paper, we consider the technology of developing a miniature microstrip device, which can be used in small space satellites and other aircraft, for which mass and dimensions are important. Modeling was carried out in the program for electrodynamics analysis of radio electronic devices in the NIAWR Desi...

Morphological and structural characterisations were carried out on the layers of TiN lodged on the silicon substrate with orientation (100). The analysis of the crystalline structure of TiN films was performed by X-ray diffraction (XRD), using a diffractometer high resolution, using radiation Mo K? . The Atomic Force Microscopy Analysis (AFM) has followed the assessment of the influence of important parameters of the filing process (temperature, polarity of the substrate) on the surface morphology and the roughnes...

The structure and the properties of the oxide nano-composition coatings formed on titanium in the diphosphate based electrolytes by means of plasma electrolytic oxidation in the spark-discharge regime at application of interelectrode voltage 100 to 130 V have been studied. The possibility to obtain the oxide layers containing the alloying elements by the modification of the composition of electrolytes has been stated. The chemical and phase composition as well as the topography, the microstructure and the grain si...

This paper presents studies on the development of nanocomposites based on rubber and layered nanoclay such as organically modified montmorillonite. The effect of introducing nanoclay in a mixture based on ethylene-propylene-diene terpolymers filled with precipitated silica was analzyed in comparison with a mixture based on natural rubber filled with an organic filler, starch. Mixtures contain 0, 3 and 6 parts nanoclay respectively to 100 rubber parts. Mixtures were obtained in a Brabender mixer. Curing agents: di(...

A technical progress in various fields of the national economy is accompanied by escalating aggression of the environment that complicates the protection of different objects made from steel, which is the main modern constructional material. Because of the corrosion attack, 50 million tons of metal is oxidized and lost almost forever every year for a mankind. In industrialized countries, annually average losses from corrosion equal to 3 - 5% from the gross domestic product. The damage from corrosion comprises not ...

A wide range of researches demonstrated that the application of nanotechnology can improve the performance of other traditional construction materials, such as concrete, steel, glass, paint, coatings, insulating materials, et. al. Noteworthy improvements in concrete strength, durability and sustainability are being achieved with considered use of metal/metal oxide nanoparticles and engineered nanoparticles (carbon nanotubes and carbon Nano-fiber), and environment-responsive anticorrosion coatings formed using Nano...

Metal Oxide based Varistors are basically ceramics, acting as n ? semiconductors, having a poly-crystalline and dense structure. The main application of these power electronic devices is for construction of overvoltage protection equipment (for every voltage level), because of some advantages like: an increased level of non-linearity between the current and the voltage characteristic, a high energy adsorption capacity and an excellent good response time, which make them ideal for protecting other sensible electron...

This work is devoted to obtaining and characterization of wood-mineral composites based on wood debarking waste and basalt screenings, which have improved ecological,strength, sound and heat insulation properties. To achieve this goal, the following tasks were solved: the regularities of the process of spontaneous filling of the porous space of the wood matrix with mineral fine particles due to the capillary forces of plant raw materials were established; simulation models of the structure and functional propertie...

The necessity of fulfilling as many conditions as possible in the specification resulted in the creation of composite materials. This idea developed in the aerospace industry was later used successfully in all industrial branches. The two materials that have been used are chemically distinct, each of which retains its properties in the composite, but provides the assembly with different properties and characteristics. Thus, for the continuous phase, the matrix was used an aluminum alloy, and for the discontinuous ...

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...

Erythromycin (E), a hydrophobic macrolide antibiotic, is prescribed for the treatment of acute bacterial infections, such as respiratory, urine, skin, and mouth infections. The main disadvantage of ER is its poor water solubility (2 mg/mL) that limits both formulation using hydrophilic bases and skin permeability. Cyclodextrins (CDs) are biocompatible cyclic oligomers of glucose, with a hydrophobic core and a hydrophilic exterior. CDs are used to improve the bioavailability of drugs by increasing their solubility ...

Mesoporous silica nanoparticles have recently attracted researchersпїЅ attention by opening a new perspective on the development of new drug delivery systems. Such mesoporous materials are characterized by a uniform distribution of pore size, welldefined walls with a high volume that enables functionalization at the level of silanol group, having a large specific surface and good hydrothermal stability. The objective of this study is the synthesis and characterization of MCM -48 and KIT-6 silicate matrices, biomat...

The paper considers the problems that arise in the process of seeding in the production of sapphire single crystals by the method of Kyropoulos. This stage is the most important in the entire technological process, but at the same time the least automated. An approach is proposed for visualization of this stage, using technical vision. It is based on the processing of images received from the ip-camera. To observe the dynamics of growth and the crystallization front at the stage of seeding, we reviewed different a...

Machinery from all industries is subject to aging processes. For economic and time reasons, damage cannot be repaired by replacing worn or damaged parts, but the product must be reconditioned. One of the most used reconditioning technologies in the industry is welding. Reconditioning technologies are credible, when samples are tested standardized. In most cases, welded structures have undergone various types of destructive tests: tension, compression, torsion and fatigue.[1] Since fatigue tests cannot be made duri...

The fruit represents the group of foods with vegetable origin, very precious from nutritional point of view, rich in carbohydrates, cellulose, minerals and organic acids, needed daily for the human body. A popular form often used for preserving fruit in cold periods, are fruit compotes which occupies an important place in our daily diet. Pineapples and mango fruit are consumed fresh, cooked, juiced and also can be preserved. The aim of the study was to evaluate some physicochemical characteristics (pH, total solub...

The possibility of manufacturing compact accelerometer based on prefabricated elements has been shown. Since most of the sensitive element designs at the lowest cost possible to produce at different ranges of sensitivity, so accelerometer design will be flexible in terms of wide range measuring of linear accelerations. Paper describes an original method of calibrating an autonomous unit of accelerometers. Without the use of precision rotary tables, centrifuges, and independent of the vibration reason, it is possib...

The properties of aluminum and its alloy make them to be the first choice as manufacturing materials for different equipments and accessories. The light weight, high strength and improved corrosion resistance recommend aluminum and its alloy to be used specially in transportation and construction industries. The native aluminum oxide film formed after exposure in air presents voids and cracks and the exposure aluminum parts to corrosive environments which lead to the degradation and reducing their lifetime. In ord...

Surface modified superparamagnetic iron oxide nanoparticles (SPIONs) are a kind of novel functional materials, which have been widely used in the various areas. The main requirements to magnetic nanoparticles for biomedical applications are the nontoxicity, biocompatibility and high-level accumulation in the target tissue or organ, chemical stability, simplicity and reproducibility of synthesis. The composition and characteristics of the SPION surface have a strong influence on their stability, distribution, and b...

The present research is a part of the obtaining innovative medicine domain and is concerned with conceiving and developing new anti depressive medicines, endowed with a high therapeutically degree, low secondary effects and impact on the quality of life, through a research partnership. The impact of Borderline personality disorder (BPD) diseases, especially depression, is continuously growing and as a treatment, are used anorganic products based on lithium, such as lithium carbonate, lithium citrate or lithium oro...

In the automotive industry, but also in other sectors, since the 80s one of the most used methods of reconditioning is welding. In this way, various technologies have been developed for each batch taking into consideration their characteristics and use. To observe and determine the correctness and economic impact of these technologies, the samples must be checked by different types of destructive and non-destructive standard tests.The most demanding destructive testing on samples is the fatigue test with alternati...

High performance environmentally friendly aqueous adhesive nanodispersions for shoe manufacture were obtained by improving the polychloroprene adherence by chemical grafting of polychloroprene latex DISPERCOLL C 84 with methyl methacrylate in the presence of benzoyl peroxide as initiator. Grafting is demonstrated by the absence of monomer and polmethylmethacrylate in dispersions, decreasing of intensity of some bands assigned to polychloroprene as well as broadening and splitting of its C-C stretching band due to ...

Worldwide there is a need to develop new advanced materials based on silicone elastomers with high-performance properties, reinforced with nanoparticles. The curing process as a primary step has a major impact on the properties of the final product, including the determination of the optimal amount of reinforcing agent in the nanometer range and cross-linking agent (peroxides - specific to food, pharmaceutical, medical and consumer goods industries). The aim of the study is to obtain an antibacterial elastomer com...

The paper presents an automatic sorting process of different color pieces. This paper is the result of a multidisciplinary depth study focused on industrial automation field more specifically on robotics, informatics, or control of the flexible manufacturing systems. The hardware and software system is formed by a robotic arm, a color sensor, sensors, a conveyor, a system of outlet cubes and a storage system, a transporting system for the robotic arm. The goal of this paper is to remove cubes from the deposit use ...

In past decades design of experiments and simulation analysis have been recognised as powerful tools for resource efficiency improvement in various areas of technics and technology, especially for energy-consuming industries such as ceramics production. Silicon carbide ceramics is widely used for structural applications, yet production of such materials invokes high temperatures and sintering aids, thus it becomes an important task to carefully adjust ceramics compositions and methods of manufacturing. Promising s...

During the last decades, problems related to environmental pollution have become even more acute. Therefore there is a need for new sources of a clean energy. Steam reforming of alcohols, which are much morechemically active, proceeds at considerable lower temperatures. It is important also that alcohols produced from biomass (bio alcohols) can be considered as a renewable raw material. The aim of this work were the development of catalysts based on the complex oxides (ZrO2 - Al2O3 - CeO2) support and the study of...

The goal of the present study is to evaluate the use of mesoporous silicate nanoparticles MCM-41 for the loading and release of the magnolol. MCM-41 has a hexagonal arrangement of mesopores, with diameters ranging from 2 to 10 nm. The homogeneity of the cylindrical pores, high surface area with uniform porosity, and good thermal stability, which make them an attractive molecular sieve for applications in sorption of large organic molecules, as well as host for quantum confinement of guest molecules. Also, the bioc...

The purpose of this paper was to study the effect of carbon content on the dimensional characteristics of some powder metallurgy (PM) materials. The powders used in this study are atomized pure iron and prealloyed iron-based powders with Cu, Ni and Mo. Some elements as copper, nickel, molybdenum, manganese and phosphorus are the most common alloying element added in powders form because of its low cost, availability and capability to improve the properties of alloys. The particle size of the analyzed powders is ra...