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Neural network method is used to solve complex modeling problems such as classification, estimation and pattern recognition. There are two main categories of ANNs which can be applied whether in regression or classification: the supervised and the unsupervised. In supervised model, all the data is labeled and the network is learned to predict the output values from the input data as previous experimental. In unsupervised model, all the data is unlabeled and the network is learned to inherent structure from the inp...

Testing of synthesized magnetically separable catalyst (Pd-Fe3O4/HPS) was carried out in the selective hydrogenation of 2-methyl-3-butyn-2-ol to corresponding olefinic alcohol and also in the Suzuki cross-coupling of 4-bromoanisole and phenylboronic acid in a shaker-type glass batch reactor. In the case of selective hydrogenation, the use of Pd-Fe3O4/HPS was found to result in 94% selectivity at 95% of the substrate conversion that is typical for preliminarily reduced Pd/HPS catalysts. Regarding to the Suzuki reac...

Aqueous-dispersion acrylate compositions with different contents of silica nanoparticles (NP) were prepared, which allowed to obtain top transparent coatings with improved abrasion resistance. The nanoscale silica used in the work was obtained by a gas-phase method using high-frequency induction discharge (HFI) in the air atmosphere. The average size of silica nanoparticles measured by transmission electron microscopy (TEM) and laser scattering was 23.5 nm. TEM photos of silica nanoparticles showed that silica was...

In this paper, a pipeline implementing a multi-scale approach that can be used for modelling different steps of aerogel production is presented. Closely integrated modulesfor aerogel structures generation, properties prediction and adsorption, diffusion and chromatography processes modelling provide various options for systematic and comprehensive study of aerogels by performing computational experiments, which allows to reduce number of laboratory experiments. The results of pipeline validation are presented for ...

This study has its aim to compare the performance of modern structured and unstructured catalysts in a dry reforming of methane (DRM). DRM is used to obtain a mixture of H2 and CO with almost equal fractions of both products, which is subsequently used in synthesis of some chemical valuable products. The kinetic scheme for tungsten carbide (WC) catalyst was taken from the literature. Using the experimental data for a fixed bed catalyst, we have fitted the parameters of the kinetic scheme of DRM on WC catalyst. The...

Due to the increased consumption of S420NL thick steel plates, the world steel price is expected to decrease. The main purpose of this investigation is to find an optimal solution both from a technical and commercial point of view to produce heavy plate 40 mm thick microalloyed S420NL hypoeutectoid steel. The imposed resistance class for this alloy is 420MPa with proven tenacity properties at temperatures up to-50 В°C. The experiment encompasses the necessity of defining a metallurgical route including chemical co...

The use of corrosion inhibitors in the paint materials is an important task, since inhibitors often cannot be included individually in the paint formulation directly. In this case, corrosion inhibitor having a high affinity to the surface of a substrate and a plasticizing effect in relation to the film-forming base of the formed coating can have a negative impact on its adhesion and physical and mechanical properties. One of the ways to eliminate this disadvantage is the use of immobilized inhibitors, in particula...

Last years the use of sub- and supercritical fluids in the catalyst synthesis is a great attention. Because of the unique properties subcritical water allow synthesizing the metal-based catalysts with the desired size, dispersity, structure and morphology of the active phase. In this work, we report the study of the structure of polymer-based Pdcontaining catalysts synthesized by hydrothermal deposition. It is shown that the use of palladium chloride as a metal precursor decreases significantly the specific surfac...

Gallium phosphide is a semiconductor material of great interest for new LED technologies. Porous AIII?V are of great interest because of their interesting optical properties different of those for bulk material. The main goal of this research work is to obtain nanostructured porous gallium phosphide (por-GaP) layers by electrochemical etching of the monocrystalline (100) p-type GaP substrate surface. The structure and surface morphology of obtained samples were studied by scanning electron microscopy (SEM), atomic...

The goal of the work reported in this paper is to describe and develop an artificial neural network (ANN) to evaluate the effect of processing parameters such as density, pressing and sintering time on microstructural characteristics including porosity and microstructure of some iron-based powder metallurgy (PM) materials. There are various methods for generating models to predict the the effect of processing parameters. The materials used in this study are prealloyed iron-based powders. The particle size of the p...

Skin cancer is a disease with an increasing incidence due to its complex etiology and various forms of manifestation. The topical treatment can be a successful therapeutic approach in early diagnosed cutaneous neoplasm. The main drawback of the drugs currently in use is the low bioavailability caused by many pathophysiological and pharmaceutical factors. The aim of the present study was to develop new modifiedrelease topical products by encapsulating bexarotene into biocompatible silica matrices and by formulating...

Recent developments in the existing molecular genetic tools have augmented our current understanding towards the deleterious effects of nanoparticles on human health. During building construction, the rapid generation of nanoparticles has greatly affected to human with severe toxicity by generating free radicals inside their body as potential health hazards. However, there is still need of analyzing nanoparticle toxicity based on the type of microbial diversity present on surface and its potential impacts on human...

In the present study, an image porcessing analysis of porosity in some iron-based powder materials was proposed. The specimens analyzed were produced from atomised iron powders of different sizes (< 45, 45-63, 63-100, 100-150, >150 ?m). The analyzed powders were compressed in a mold using uniaxial pressing and the applied pressure was 600 MPa with the disc dimensions of ? 8 ? 6 mm. The compacts were sintered at a temperature of 1.150 В°C with the sintering time of 60 and 90 minutes. The sintered specimens obtained...

The research consisted in obtaining Ni-P and Ni-P-Al2O3 coatings followed by heat treatment and characterization of heat treated and untreated layers. The layers were deposited on the steel strip, by electroless method to certain process parameters. To obtain the Ni-P-Al2O3 nanocomposite layers, 5 g/L Al2O3 particles of 20 nm were introduced into the nickel bath, and it has been worked with the same parameters as to obtain the Ni-P layer. The samples were heat treated at 300 0C, 400 0C and 5000C for one hour in a ...

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 ...

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...

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 ...

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...

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...

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 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...

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...

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...

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...

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...

The objective of the study was to evaluate the effect of processing parameters such as pressing and sintering time on microstructural characteristics including porosity and microstructure of some iron-based powder metallurgy (PM) materials. The powders used in this study are prealloyed iron-based powders. The particle size of the powders is ranging from 45 to 150 ?m. Following mixing the powders with zinc stearate 1% for 30 minutes, the studied powders were single pressed in a die at a pressure of 600 MPa. Zn-stea...

Based on a previous research, a thermal bimorph actuator was used for a development of a micromirror element. An existing technological process for the manufacturing of IC was used as base for micromirror. An analysis of the available construction materials was made, on the basis of which a choice was made for silicon as the main material for the micromirror, aluminum as the reflective coating and the first element of the bimorph beam, and silicon dioxide as the second element of the bimorph beam. ? polysilicon he...

Anthocyanins are known as safe colouring materials, although they have poor stability which often limits their use. To solve this drawback, mesoporous silica with high surface area was used as an adsorbent for anthocyanins. This study proposes the enhancement of the anthocyanins photo stability by their incorporation into the pores of mesoporous silica containing various metal ions. The anthocyanins were adsorbed on the silica by pouring a highly-concentrated anthocyanins solution to the dried silica. Improved sta...

Polyoxometalates (POMs) are discrete, anionic metal-oxygen clusters of early d bloc metal ions in high oxidation status (e.g. MoVI, WVI) with a very large structural and compositional variety, leading to interest in many different areas (catalysts in homogeneous and heterogeneous catalytic oxidation of organic compounds or biochemical reactions, activity in enzymatic redox processes, as antitumoral, antibacterial and antiviral treatments etc). An important subclass of POMs is the {XMo6O24} structure type, Anderson...

Phosphate removal from wastewater is necessary at sewage treatment plant before discharging into the natural streams due to many reasons especially to preserve phosphate and to avoid eutrophication. Magnetite nanoparticles stabilized on ZSM-5 zeolites were used to adsorb, remove and recover phosphate from said wastewater. Three samples namely, magnetite, magnetite@ZSM5 and ZSM-5 were used for batch adsorption experiments. Results indicated the highest phosphate removal efficiency for magnetite@ZSM-5 material. Magn...

1050 aluminum alloys are used in the conventional engineering applications where the increased corrosion resistance is required (e.g. automotive industries or construction, containers). Improving the corrosion resistance of 1050 aluminum alloy is an extensively studied topic. Different methods are applied to improve the corrosion resistance of 1050 aluminum alloy as: painting, waxing, zinc-chromate priming, thin layer of pure aluminum, coatings with a liquid protective solution, conversion coatings and also anodic...

In this article, the authors have analysed the influence of ultrasound, used in the quenching from the intercritical range (? + ?), on the volume fraction of martensite in the microstructure of a dual-phase steel with 0.087% C and 0.511% Mn. The ultrasonic oscillations, applied to the medium in which the quenching takes place, under the action of pressure and cavitation phenomenon, destroys and prevents the formation of vapor and gas films, thereby ensuring a more prolonged contact between the workpiece and the co...

In this work, the organic silicon-based composites were obtained from resorcinol, formaldehyde, TEOS, N-(b-aminoethyl)-g-aminopropyl-trimethoxysilane (AEAPTES) as initial materials for carbon-silica composites producing. The solvent was acetone, those molar ratio to resorcinol varied in following: sample S1 ? 1:11; sample S2 ? 1:14 and sample S3 ? 1:19. Gels were prepared by one-stage method. The silica-organic gels were supper-critical dried. It was shown that the heat treatment of silica-organic gels allows gett...

Recent surge in the number of studies on inorganic nanoparticles has raised concerns over possible commercial implication of the same. The developmental stage of regulations and standards controlling the same amplifies this problem. In this perspective, we tried to analyze the current trends on lignocellulose nanomaterials (viz. Nanocellulose and lignin) and its global potential to offer an environmentally benign alternate. We used number of studies indexed in Scopus database to get an idea of trends. An additiona...

The aim of the present work is to develop, substantiate, and study a fundamentally new method of derivation of composite electrolytic films making it possible to control their composition and structure. We assume that, after the termination of the stirring-up of a bath containing the electrolyte-suspension with monodisperse spherical particles of the same density, a uniform sedimentation space is established. The upper boundary of this field will descend with a velocity depending on the dispersity and density of a...