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Atmospheric air is the primary component used in air separation plants. Wet air is a mixture of dry air particles and vaporous water particles, a mixture in which the components do not chemically interact and are thought to be approximately perfect gases. Atmospheric air to be processed in a separation unit needs to be cleaned of all impurities that can cause damages in the main components of the plant. The hazardous impurities that can be found in the atmospheric air used to generate oxygen, nitrogen and rare gas...

An electrolyte for chromium based nano-composite electrolytic coatings (nano-CE?) obtaining has been developed. Nano-CEC was applied on steel of the St 3 brand with constant exposure to ultrasound, electrolyte temperature 50?60°?, current density 7kA/m2 for 1 and 2 hours from two variants of chromium-plating electrolytes, differing in the fact that one electrolyte contained strontium sulfate, in the other ? without it. Quantitative assessment of the corrosion resistance of nano - CEC deposited on steel St.3, was e...

This study aims to investigate the functionalization by pad-dry-cure method of 100% cotton fabrics with colloidal dispersions based on TiO2:N and SiO2 nanoparticles (NPs) in different molar ratios (1:0.5, 1:1, 1:1.5 and 1:2). For the preparation of colloidal dispersions the chitosan was used as stabilizing agent. Self-cleaning performance of the functionalized samples was qualitatively assessed based on Methylene Blue and Brilliant Green stain removal ability under UV radiation. Stain photodegradation efficiency w...

In this paper we present the results obtained regarding the functionalization of the surface of sheepskins using nanocomposites based on reduced graphene oxide - TiO2-Ag and reduced graphene oxide - TiO2-Cu in order to obtain leather with antimicrobial and photocatalytic properties. The nanocomposites were integrated in film forming polymer composites and were applied by spraying on sheepskin surfaces. Sheepskin surfaces were characterized using scanning electron microscopy (SEM), physico-mechanical methods, photo...

The aim of this work was to obtain new medical biomaterials based on a biocompatible polymer polytetrafluoroethylene (PTFE), modified with the drug, ketoprofen (KP), and gold nanoparticles (Au NPs). The biological inertness of PTFE, hydrophobicity, elasticity, low weight prevents sticking to wounds and makes fibrous materials based on it ideal for dressing and obturators. Ketoprofen gives anti-inflammatory properties to the material, while Au NPs provides it with antibacterial ones. Biomaterials based on porous PT...

New materials based on Au and Ag nanoparticles stabilized in a matrix of microcrystalline and bacterial cellulose were prepared for medical applications. Au and Ag nanoparticles were synthesized in i-PrOH by metal vapor synthesis (MVS) and incorporated into the polysaccharide matrix using metal-containing organosol. The MVS is an efficient route of purposeful synthesis of metallic nanoparticles and their derived composites. Microcrystalline cellulose brand Avicel PH-101 with a polymerization degree of 180 and an a...

Molecular simulation methods were used to describe the spiral-structure of halloysite (7 A) loaded with irinotecan in Materials Studio modeling environment. Halloysite is a clay mineral commonly used as a drug delivery system for a variety of molecules due to its suitable characteristics and its morphology. Irinotecan is a semi-synthetic drug used in the treatment of colorectal cancer and exists in an active lactone form and an inactive hydroxyl-acid anion form[1]. In this work, the anionic form of the irinotecan ...

The qualitative and quantitative composition of biomass of microorganisms has been studied in key points of artificial biocenosis: water filter, duckweed and pond snail. Metagenomic studies have shown the presence of Bacteroides and Proteobacteria types in all examined systems, however, specific representatives - Actinobacteria, Cyanobacteria, and Bacilliwere also found, respectively. A microflora peculiarity of water filter was the presence of actinobacteria. In the intestine of the pond snail (Lymnaea stagnalis ...

Micro and nanoparticles of titanium dioxide are nowadays produced worldwide for a range of applications. In our project we focus on potential use of titanium dioxide particles as UV absorber (anti-UV protective coating) for wooden construction structures. We investigate the influence of different synthesis methods on particles? morphology. Hence, material characterization has an important place in our research. Electron microscopy is a powerful tool to obtain information about the morphology of particles and their...

The paper deals with a design and a method of milling of the invention called ?Milling device for mechanical treatment process of fine particles?. The milling device for mechanical treatment process of fine particles according to the present invention consists of a lower flange with a milling chamber having an external part and an internal part being fixedly attached to said lower flange wherein an elastic doctor blade with brushes is arranged within said internal part. The elastic doctor blade with brushes is fas...

Directional couplers can divide the input power between its outputs in different proportions. This is due to the ratio of wave resistances between two pairs of quarter-wave segments. Due to the fact that at frequencies of 2 GHz and lower couplers are also actively used, it is necessary to take care that their dimensions satisfy the radio system where they will be installed. Due to the fact that it is not always possible was investigated miniaturization as an opportunity to reduce the area occupied by the branch wh...

It is known that one of the methods for purifying gas fraction from hydrogen sulfide is amine treatment. Various types of amines are used to remove hydrogen sulphide, carbon dioxide and carbon dioxide from petroleum gases. The choice of specific amine depends on the needs of the process. Mono-ethanolamine (MEA) (C2H4OH) NH2 and diethanolamine (DEA) (C2H4OH) 2NH are commonly used. Both are ammonia derivatives. To develop recommendations on the choice of material from which to make equipment for amine plants, compar...

New ways in the field of extinguishing by solid extinguishing is aerosol fire fighting originally developed in the 1970s by the Russian space research agency called ?SOJUZ?. More significant development in the aerosol fire extinguishers usage occured in Europe in the 1990s. Carbon as basic element of organic compounds with two allotropic modifications can be found in various modifications like diamond and graphite. Fullerenes as the third modification was discovered in 1985. Detailed analytical researches have fou...

The process of mixed oxide coatings forming on a high-silicon aluminum alloy in the cobalt-containing pyrophosphate electrolyte by the plasma-electrolytic oxidizing (PEO) method is studied. It was shown that AL25 chemical composition heterogeneity causes the consumption of part of the anode current to homogenize the treated surface, which is reflected in minimizing the content of doping components at the initial processing stage. It was established the growth of mixed oxides Al2O3·CoxOy relative mass to be a funct...

Inorganic arsenic is in very small concentrations a common constituent of surface and groundwater. However, its increased concentration may pose a significant risk to human health in connection with its carcinogenicity (a proven human carcinogen). Therefore, it is necessary to address the reduction of its concentration in drinking water using the most efficient and financially undemanding techniques. The paper analyzes current and new trends in the field of removal of arsenic from drinking water. It focuses mainly...

Treating depression is a complex process, which includes medical treatment and also psychotherapeutic approach. These two approaches are working together. There is a large scale of known treatments for depressive disorders, which had been developed since the 1950s and the therapeutic effectiveness and patient tolerance were assessed through generations. Among the studied variants, anorganic products had been Among the studied variants, anorganic products had been Among the studied variants, anorganic products had ...

Adjustment of compositions and processing techniques, mainly ? firing conditions, has been a key route for ceramics performance improvement. The present research addresses sintering process of alumina ceramics with an additive in system that was studied by non-isothermal method. Experimental samples shaped as cylinders 25 ? 6 mm in size were obtained and sintered by consequtive firings in air at heating rates q1 = 1,0 and q2 = 3,0 °?/min without curing and quenched in air. Linear shrinkage (? = ??/?, hereon ? ?) a...

Novel micro and nanostructured bioemulsions were created by innovative technologies based on fibrillar cellulose/titanium dioxide/(surfactants mixture: dodecandioyl-diglycine and sucrose diester/ethanol/water, for improved surface properties development with applications in leather industry. The high potential of using cellulose as a material for various applications: in membrane technologies for pollutant absorption, in pharmacy, etc. opens the way to obtaining new added value materials (hybrid micro and nanocomp...

Currently, the issue of the possible negative influence of nanoparticles on human health is inadequate in comparison with the presentation of their positives. Although there is no questioned their undeniable importance on the other hand experts agree that the precautionary principle and related measures are missing and necessary. The paper presents the pilot results of a grant project focused at the creating a methodological guideline aimed at increasing the level of occupational health and safety management at wo...

The influence of ?-ferrite amount ferrite in AISI 321 steel on its general corrosion, critical pitting temperature and potential in simulated circulating waters. The samples were made in the form of rectangular 3x3x1 mm parallelepipeds by cold mechanical method. Surface of the samples was subjected to electro-polishing. The amount of ferrite phase was determined by empirical formula. It was established, that after electromagnetic saturation of the samples, ?-ferrite content in five heats of AISI 321 steel was calc...

The study was conducted to study the effect of cerium dioxide nanoparticles on the survival of zebrafishand the microbiome of their intestines. With respect to the intestinal microbiome in the control group, it was registered that the majority of the identified bacteria belonged to Proteobacteria. A peculiar action of CeO2nanoparticleson the intestinal microbiota was an increase in the number of Firmicutes, in particular, Bacilli class bacteria, and a decrease of Proteobacteria phylum, it was manifested in the flu...

The paper describes a new design of a directional coupler with four plug-in quarter-wave loops. Four loops increase the operating frequency band several times, but the area of the device also grows by two quarter-wave segments in length. It is not always possible to use such a large device area, for this reason, techniques are used to reduce the size of the device with minimal loss in its characteristics. Using miniaturization, which is the use of compact structures, it was possible to reduce the size of a quarter...

Acrylic derivative-based superabsorbents are widely used currently in agriculture as the soil conditioners, plant growth regulators, etc. Their usage has a positive effect on the growth and survival of the plants cultivated in the arid regions. However, the effects of hydrophilic acrylic polymers on the soil microbiocenosis still remain unknown. The influence of the moisture-absorbing acrylic acid-based hydrogels with different concentration of bentonite filler was studied on the soil microbiota. N,N-methylenebisa...

In this paper we describe the synthesis and characterization of nano-sized TiO2 particles supported on sepiolite fibres with sepiolite to TiO2 weight ratios of 30:70, using sepiolite from Korinthos, Greece. Sepiolite - TiO2 nanocomposites were prepared by deposition of anatase form of TiO2 on the sepiolite surfaces using a sol?gel method with titanium isopropoxide as a precursor under hydrothermal treatment at 180 °C. The characterization includes phase composition, particle morphology, while the physical properti...

Based on the exergetic analysis the paper analyses the conduct of a simple Linde cryogenic refrigeration cycle looking for its weaknesses and trying to find ways for operating or structural improvements. The exergetic analysis reveals that a major exergy destruction is due to heat transfer across a finite temperature difference in the recuperative heat exchanger. The optimization procedure points out that this exergy destruction reaches a minimum if the temperature difference between the high (hot) and low pressur...

Directional couplers are widely used in microstrip technology, but their dimensions are tied to the operating frequency. Since the smaller the frequency, the longer the longitudinal length of the quarter-wave segments and the greater the overall dimensions of the coupler. For this reason, use miniaturization, which allows to reduce the area occupied by the device on the substrate, with negligible loss in performance. In addition, there is an economy of the material used in the manufacture of the microstrip device....

The goal of this work is to study the processes of producing carbon aerogels, silica-carbon aerogels and CNT-silica aerogels and search for new areas of their applications. To achieve this goal, aerogels using the sol-gel method and the supercritical drying process were synthesized. The analysis of the obtained aerogels was carried out using the methods of nitrogen porosimetry and scanning electron microscopy. In addition, a software that uses cellular automaton models to generate virtual structures of the studied...

Microstrip directional couplers are made on microwave substrates, which consist of various dielectric materials. With a decrease in the operating frequency, the dimensions of the coupler increase, and more material is required for their manufacture. To reduce the consumable material, you can use different approaches to miniaturize the couplers, this will reduce the size of the device while maintaining its characteristics. So this article presents the results of research to reduce the occupied area of a flat crosso...

In the vegetable growing field, the germination is an important indicator in the appreciation of seeds quality. The process takes place over a variable period of time being influenced by a number of factors such as species, environmental conditions and the treatment applied to the seeds. We used citrate - stabilized gold nanoparticles to prevent the occurrence of fungi and to stimulate the germination process of carrot seeds. The gold nanoparticles were synthesized by mixing and heating aqueous solutions of chloro...

Aerogels are promising materials for use in various industries such as chemical, pharmaceutical, medicine and food industry. These highly porous materials have unique properties, including high adsorption capacity, which makes it possible to successfully impregnate various substances into aerogels: active pharmaceutical ingredients (APIs with low solubility and bioavailability), various oils (for example, high volatile), additives for the food industry (vitamins and aromas) and many others. The aim of present inve...

A passive method is proposed in this research for minimization of the temperature drift of a strapdown inertial navigation system with fiber optic gyroscopes and accelerometers by means of reduction of the temperature differences between the structural components of individual gyroscopes as well as between gyroscopes and accelerometers. For this purpose, theoretically possible use of nanostructured composite materials based on carbon nanotubes and characterized by increased thermal conductivity in individual struc...

This research deals with the aspects of use of the heat balance method for calculation of three-dimensional non-uniform non-steady temperature fields of complex optoelectronic systems through the example of a measuring unit based on fiber optic gyroscopes and microelectromechanical accelerometers. The main principles of and approaches to development of a mathematical model of the temperature field of the unit under consideration on the basis of the heat balance method have been set forth. The adequacy of the devel...

In this paper, a computational method to predict the corrosion resistance of some ironbased powder metallurgy (P/M) materials is proposed. The samples prepared from atomized iron powder and pre-alloyed iron base powders powders were the materials analyzed in this paper. The compacted samples were obtained by powder metallurgy process, respectively pressing and sintering of the mixed powders. The samples were compacted at a pressures of 400 and 600 MPa. The sintering temperature was approximately 1.150 В°C. The inf...

SF6 insulating installations are today the most performing technical solution applied to high voltage devices such as circuit-breakers and surge arresters. This gas is used due to a lot of excellent insulating properties. These properties are depending on many variables, one of them is electrodes? geometry and material. Generally, when studding the dielectric breakthrough process, ideal electrode surfaces are taken in consideration. But many experimental results, different than theoretical ones, could be a consequ...

In all industrial branches, the last period is under the sign of economic progress, but with the lowest energy consumption and the lowest possible release of pollutants. Technologically, therefore, the removal of polluting technologies and the introduction of new "environmentally friendly" technologies are being sought. Thus, the new industrial trend is to reduce the use of molded or forged semi finished products and the introduction of cold rolled semi finished products or other processes. This transformation can...

This paper describes the design of a new product, conceived by the authors, part of a research contract and of a technological transfer, from university to the industrial market. It is a low voltage class C surge-arrester, based only on metal-oxide varistors, designed for low voltage residential equipment. Located in the indoor interior connection boxes, it could protect the whole installation against any type of occurring overvoltage (pulsed or long time one). The results of the applicative research were transfer...

Nowadays, wearable devices represent an intensely-used technology, which helps us keep track of various vital parameters. It is a great development, its impact on society being described simply by the success among users. The data provided by wearable devices can be easily integrated with wireless sensor networks, leading to successful Internet-of-Things applications. The purpose of this paper is to analyze the current stage of wearable technology, as it represents fast and simple data sharing. These make it is es...

The purpose of the paper is to obtain a new composite material based on chemically functionalized nanoparticles dispersed in plastomer matrix. The dispersion of the TiO2 hybrid nanoparticles (filler) in a plastomer matrix (polyvinyl chloride-PVC) leads to a high-performance polymeric material with multi-functional, antibacterial, and plastomer-specific processing properties. The materials are suitable for biomedical and food industry applications and will be tested in terms of long-term stability, and antimicrobia...

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...

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...

Nowadays, protection of any sensitive electric equipment against any type of overvoltage (including lightning applied on power networks) is a big challenge for the power electronics domain. The most advanced and reliable devices used in order to perform this operation are metal oxide varistor based surge-arresters. These polycrystalline ceramic varistors are made of a mixture of different metal oxides, where the main ingredient (more than 80-90% as mass concentration) is the ZnO. The real improvements of these dev...

Autoimmune diseases affect approximately 5% of the population worldwide. Generally, these disorders induce high degree of morbidity and disability and therefore, they have a significant social and economic impact. The precise diagnosis of specific autoimmune response is necessary for adequate treatment of the patient. Accordingly, the diagnostic assays for autoimmune diseases are continuously developing and improving. Biofunctionalized nanoparticles represent a promising novel approach in this field. Our group has...

The authors used a modern quantum theory allowing to determine the energy levels of electrons in real metal. What's more, the presented model allows to define the electrons energy density and consequently use the Gibbs ensemble theory. In combination of quantum theory and Gibbs statistics, the authors obtained analytical equations for both the work function and the bulk modulus of metals. Based on the obtained equations, the work function and the bulk modulus for Ti and several other metals were calculated. It sho...

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...

Rehabilitation techniques ?weld toe grinding? and ?WIG remelting weld toe? have an beneficial influence on the increase of the fatigue life of welded structures by reducing the stress concentrators at the intersection between filler and base material. This stress concentrators reduction is achieved by increasing the radius of the connection between those two elements of the welded joint, horizontal and vertical plates. From those two techniques mentioned above, the technique that causes the greatest fatigue life i...

Variable stresses where the load value varies between a maximum and a minimum value, or varies the position in time, cause after accumulating a large number of load cycles in those structures, the fatigue failure. Fatigue is characterized by failure on values of the applied stress from the load cycles, below the material yield, values which in case of static stress would not have caused problems. Knowing that the variable stressed structures are sensitive to stress concentrators, the paper aims is to highlight the...

New hybrid materials based on copper nanoparticles stabilized in an ultimately biocompatible chitosan matrix were prepared via metal vapor synthesis. Transmission electron microscopy shows that the particles have predominantly spherical form, polydisperse character, the mean diameter about 2-4 nm and a rather uniform distribution in the chitosan matrice. X-ray photoelectron spectroscopy of Cu-carrying chitosan powder obtained by impregnation of chitosan powder with Cu-acetone organosol indicated two oxidized coppe...

The purpose of this paper was to develop an application to help make the decision regarding the robot model that meets the required requirements. The decision, the primary component of the decision-making system, is an essential element of management, being its specific tool of expression. In fact, the qualitative level of the leadership of an organization is manifested by the elaborated and applied decisions. In practice there are two types of decisions: the leading decision and the management decision. The decis...

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...