Nanotechnologies in Construction: A Scientific Internet-Journal @nanobuild-en
Статьи журнала - Nanotechnologies in Construction: A Scientific Internet-Journal
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Статья научная
Introduction. The porous composite and nanocomposite materials discussed in this publication are metallized carbon-graphite materials, in particular carbon fiber materials (CFMs). At metallization of CFMs one of the actual problems is the task of applying uniform metal coating on the surface of CFMs fibers over the entire volume of the processed material. One of the most effective ways to coat CFMs with metals and their alloys is the galvanic method. This method allows, among other things, to optimize the process by optimizing both the design of the electrolyzer with flow-through three-dimensional electrodes (FTE) and the choice of electrodeposition modes, such as galvanic, concentration, and hydrodynamic. Materials and methods. Methods of mathematical modeling of porous medium metallization processes and previously published experimental data were used to solve problems on calculation of operating modes and elements of the electrolyzer design, in particular, the specific reaction surface of the UWM distributed over the thickness of the electrolyzer. Results and discussion. The development of mathematical models of the processes of electroplating metallization of CFMs is carried out. Boundary value problems of mathematical physics are formulated and calculation methods are proposed. Problems of optimization of distribution of specific reaction surface of CFMs by thickness of FTE on the basis of electrochemical theory of processes in porous medium are set, ways of their solution are presented. Specific technological problems are solved. The comparison of the most effective values of the distribution of specific reaction surface of CFMs over the thickness of FTE obtained as a result of modeling with the experimental data is given. The workability of models and methods for studying the process of copper electrodeposition from sulfuric acid electrolyte is shown. Conclusion. Calculation of regularities of electrochemical processes of metal extraction in FTE on the basis of the developed mathematical models allows to predict the results of electrolysis, determine the optimal modes of operation and elements of FTE design. The use of FTE for metallization of CFMs with properly distributed reaction surface contributes to obtaining composite materials with specified properties.
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Статья научная
Introduction. Currently, carbonate reservoirs play an increasingly significant role in the global hydrocarbon balance. Most of the deposits discovered in recent years are fractured carbonate reservoirs. The potential for effective development of carbonate reservoirs lies in the development and application of new high-tech methods and advanced well drilling technologies. The article highlights the challenges of developing productive deposits in the Paleozoic basement of Tomsk region deposits represented by fractured carbonate reservoirs. The article considers the mining and geological conditions of carbonate reservoirs in the Paleozoic basement and the challenges that arise when using traditional drilling technologies. The article presents the results of an analytical review on the application of advanced technologies for drilling wells with horizontal completion. Some aspects of the application of nano drilling fluids for conditions of low-permeability carbonate reservoirs are highlighted. The content of the article is based on the author's research and analysis of publicly available literature. Methods and materials. The work is based on the generalization, systematization and analysis of factual material, scientific publications, and results of analytical studies. Results. Based on the generalization and analysis of geological and field data, the authors established that in the conditions of the identified group of fields, when developing fractured carbonate reservoirs, the productivity of a well depends on the number of natural cracks opened during drilling that penetrate carbonate rocks. Fault tectonics had a major impact on the development of highly fractured zones of carbonate reservoirs, which are the main reason for frequent absorption of drilling fluid when drilling wells with a horizontal end. Clustering of the well stock of the development object in carbonate reservoirs allowed to identify 3 groups of wells, opening up deposits with different filtration-capacity characteristics. It was established that the nature of the distribution of porosity and permeability depends on the development of reservoir fracturing associated with the position of tectonic faults. Analytical studies in the perimeter of Russian oil and gas companies have shown that the efficiency of well drilling technologies in fractured carbonate reservoirs is achieved through an integrated approach: detailing the geological structure of the target object, adapted drilling technology with the ability to regulate differential pressure in the well-formation system, as well as selecting optimal drilling fluids.
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Dry building mixes with a silica-based modifying additive
Статья научная
Introduction. The use of dry building mixes has broad potential for use in construction due to their stability of properties, the ability to provide a specific set of quality characteristics to the material, and reduced production waste. When developing compositions of floor dry building mixes, it is necessary to ensure high mechanical properties, reduce shrinkage deformations, crack formation, and provide high adhesion to the concrete base. Expanding the range of dry building mixes, using local raw materials and modifying additives for various functional purposes for their production is an urgent task for the construction industry. Materials and methods. To ensure the rheological and technological properties of the dry building mixes, low water demand binders were produced based on Portland cement, volcanic slag, fly ash and dry superplasticizer on a polycarboxylate basis. To regulate the technological properties and increase mechanical properties of dry building mixes, a reinforcing additive in the form of basalt fiber and nanosilica was used. Results and discussion. The compositions of self-leveling dry building mixes were optimized according to the criteria for achieving the highest mechanical properties. The water-holding capacity of the mixes, compressive and flexural strength, water absorption, crack width, abrasion, and adhesion strength to the concrete base were determined. The microstructure of the mortar was studied using scanning electron microscopy. An assessment was made of the influence of modifying additives on changes in the properties of flooring dry building mixes. Conclusion. The resulting compositions of dry building mixes comply with the requirements of state standard for self-leveling flooring building mixes. With the use of a complex of mineral, plasticizing, micro-reinforcing, nano-sized additives, high performance indicators of flooring building mixes have been achieved.
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Статья научная
Introduction. The effect of adhesion additive and nature of filler on fatigue life and interfacial interaction in mastic is analyzed in this paper. Materials and methods of research. Frequency sweep from 0.1 to 100 rad/s at strain 0.05% at temperatures from 30 to –10°С with a step 10°С and cyclic tests (LAS test) at temperatures from 16 to 1°С with a step 3°С for bitumen grade BND 100/130 and mastics based on it, containing fillers of different nature, were performed on the dynamic shear rheometer. Mastics were prepared by mixing bitumen (3 min; 160°С and 600 rpm) and filler (filler volume fraction – 0.275). Adhesion additive in an amount of 0.7%, was introduced into bitumen before the filler to investigate the effect of AD on the properties of bitumen and AB. The damage characteristic curve under cyclic loads was calculated using two models of VECD theory (Viscoelastic Continuum Damage Modeling System): dissipated strain energy and pseudo-strain energy. Results and Discussion. The influence of nature and properties of filler, adhesive additive, temperature and frequency of tests on the parameter of interfacial interaction K-B-G* and thickness of adsorbed layer has been investigated. The intensity of damage in the specimen under cyclic loads and the behavior of fatigue parameters as a function of test temperature at two variants of determining the parameter α have been analyzed. Conclusion. It is shown that an increase in the interfacial layer thickness in asphalt mastic leads to an increase in their resistance to damage accumulation (Damage Intensity) during fatigue testing (LAS), and lowers the rate of pseudo-deformation energy growth.
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Effect of laser modification on composite films with nanodispersed SiO2
Статья научная
Introduction. This research is aimed at studying the effect of laser modification on composite films obtained on the basis of polyimide track (nuclear) membranes and filled with nanodispersed SiO2; to change their optical and structural properties. Materials and research methods. Polyimide track (nuclear) membranes were used as a polymer matrix. Track diameter is 200 nm, membrane thickness is 25 μm. The tracks were filled with nanosized SiO2 by hydrolysis of tetraethoxysilane in the presence of track membranes. For composite film surface modification, we used ytterbium pulsed fiber laser Minimarker 2-20 A4 PA. We studied the change in the surface microscopy of composite films, their optical density, IR-Fourier spectra and surface wettability depending on laser treatment. Results and discussion. The authors have found the possibility of creating a composite film based on a polyimide track (nuclear) membrane and nanodispersed SiO2 by hydrolysis of tetraethoxysilane in the presence of a membrane. It is shown with the energy dispersive analysis method that silicon oxide has completely filled the pore volume of the track membrane. Laser modification of the composite material surface (composite film) leads to an increase in the contact angle of wetting from θ = 66.75 ± 1.55° to θ = 101.52 ± 3.03°. Thus, the material acquires hydrophobic properties. Also, the laser films modification has a positive effect on the transmittance of the films, namely, this coefficient increases. The greatest change is observed in the infrared region of еmitted spectrum, the average increase in transmission is +70.48%. Conclusion. The obtained results of the study are of great importance for understanding the mechanisms of creating composite films with improved optical properties, which can later be used to create composite films with desired optical properties for various applications.
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Effect of nanofibrillar cellulose on the cement paste setting kinetics
Статья научная
Introduction. The study addresses the effect of nanofibrillar cellulose (NFC) on the setting process of cement paste during the first hours of gauging. A brief justification of the research topic relevance is given. It has been noted that the modification of cement materials by nanoscale additives has sparked significant scientific and practical interest in recent years. NFC has emerged as one such additive, and the potential impacts of its incorporation into cement systems are currently under active investigation. The study aims at investigating the effect of NFC on the cement paste setting kinetics during the first hours of gauging. Materials and methods. We present the materials used in the research and their characteristics, in particular, two types of cement characterized by the presence or absence of false setting, as well as cement paste compositions with different NFC consumption (from 0 to 0.24% of dry matter by weight of cement). The technique of measuring conditional viscosity in time with a laboratory rheometer and a special measuring system is described. Results. The results of cement paste tests are presented in the form of setting process diagrams. Discussion. The results obtained and experimental data are given. The complex character of NFC influence on the cement paste setting kinetics has been noted, which depends on the cement quality and additive consumption. For cement without signs of false setting, a decrease in setting onset time was observed when increasing the NFC content. Conversely, increase in the amount of NFC leads to an increase in the setting onset time for cements with signs of false setting. Conclusion. NFC has a noticeable effect on cement paste setting kinetics in the first 3 hours: it accelerates the process when using cement without false setting and slows down the setting when using cement with false setting.
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Статья научная
Introduction. In the article the use of powder elastomeric modifier capable of rapid breakdown into micro- and nanofragments upon contact with hot bitumen to improve the low-temperature properties of bitumen is presented. The indicators of resistance to cracking are determined by various methods and their dependence on the thermal history of the samples. Methods and Materials. At temperatures up to –36оC the oscillatory rheological tests (4-mm DSR test) of RTFO-aged samples of bitumen BND 60/90 and modified binder (MB) which contain the active powder of discretely devulcanized rubber (APDDR) produced by high-temperature shear-induced grinding from the crumb rubber of worn tires have been conducted. MB was prepared by mixing bitumen (3 min; 160оC and 600 rpm) with 12.5 wt.% APDDR. Results and Discussion. The effect of the test parameters on the rheological parameters has been studied. Structural transitions in bitumen and MB by methods of differential scanning calorimetry (DSC) and the cracking temperature of the same samples in static conditions in the ABCD test were detected. It is revealed: a decrease in the temperature of actual cracking of the MB sample compared to bitumen. Conclusion. It is shown that APDDR as a modifier affects the structure of bitumen and reduces the temperature sensitivity of bitumen to external influences.
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Статья научная
Introduction. The article examines the problem of the development of transport infrastructure in the Solovetsky archipelago and proposes a solution to reduce the cost of manufacturing reinforced concrete slabs for the road surface. It is proposed to use saponite-containing waste (SCW) of the mining and processing plant JSC Severalmaz as a mineral additive in concrete. Studies have shown that mechanically activated saponite-containing powder (MSP) improves concrete performance and reduces binder consumption. The use of MSP makes it possible to solve the problem of waste disposal and reduce environmental damage. The purpose of the work is to assess the effect of the time factor on the hydraulic activity of the mechanically activated saponitecontaining powder, since the activity of the additive may change during long-term storage. It is known that the degree of activity of mineral components is usually estimated by the amount of Ca2+ ions absorbed from a saturated lime solution. A number of direct analytical methods are available to monitor the change in Ca(OH)2 content over time during the course of the hydraulic reaction. This technique, based on the measurement of the potential of the ion-selective electrode, is fully suitable for monitoring the hydraulic activity of the MSP. Methods and Materials. Saponite-containing waste was used as the main material for the studies, which was isolated, dried and dispersed. A mechanically activated saponite-containing powder was thus obtained. Control of the degree of grinding of the obtained finely divided MSP samples was carried out according to the specific surface area (Ssp, m2/kg). To perform potentiometric analysis, an electrode system consisting of a measuring electrode with a calcium ion detection function (pCa) and a reference electrode was used. In preparation for the experiment, the calcium selective electrode of the Elite-041 model was kept for three days in a calcium chloride solution with a concentration of 0.01 mol/L. The electrode was then washed with distilled water and calibrated to solutions with concentrations (CCa) of 10–1, 10–2, 10–3, 10–4 and 10–5 mol/L, for which pCa = 1÷5. To study the sorption capacity, a lime solution with a concentration of 0.015 mol/l was prepared, as well as a suspension from samples of fine mineral saponite-containing powder. A solution of lime with a volume of 0.2 ml was successively added to the resulting suspension by a doser, while measuring the electromotive force (potential) of the system with continuous stirring. Based on the obtained potential values (mV), the concentration of calcium ions (Сfact Ca) in the bulk phase of the suspension was calculated using a predetermined calibration relationship. Further, using the algorithm for calculating the activity parameters of powders, according to potentiometry data, the maximum amount of absorbed calcium hydroxide (ΔССaO) was determined as the difference between the Сteor Ca and Сfact Ca, and the hydraulic activity coefficient . Results and Discussion. The resulting mechanically activated saponite-containing powder had a specific surface area of 196 m2/kg (10 min), 644 m2/kg (30 min), 1209 m2/kg (60 min), 1428 m2/kg (90 min) at different milling times. The preliminary calibration dependence of the potential of the electrode pair on the pCa value is characterized by the linear equation: E = –23,23pCa+520,35. It was found that when adding a lime solution to the suspension, an increase in EMF is observed due to the sorption of calcium ions by a mechanically activated saponite-containing powder. After reaching the threshold volume of the Ca(OH)2 solution, the potential stabilizes. With a further increase in the concentration of calcium ions, when their interaction with the MSP particles ceases, the E value increases again. Further, dependencies were obtained for all batches of the experiment, the difference of which lies only in the quantitative characteristics of the functional parameters. Initial value of electrode pair potential characterizes background concentration of calcium ions determined by their residual content in water and/or MSP. The obtained functional relationships of the Сfact Ca = f(Сteor Ca) for the test samples made it possible to determine the threshold values of the concentration of calcium ions in the solution, the excess of which creates their excess in the reaction medium. The built functional dependence of the G∞ = f(Ssp), showed that the G∞ reaches its maximum value already at a specific surface area of more than 600 m2/kg (30 minutes of grinding). Since the grinding of 10 minutes has little effect on the specific surface area of the saponite powder, which affects the value of the hydraulic activity coefficient of the MSP, the dependence of G∞ = f(Ssp) for grinding more than 10 minutes was considered.
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Effective gypsum compositions with the addition of underburned ash and slag mixtures
Статья научная
Introduction. Currently, research and development in the field of nanomaterials science is being conducted worldwide. The rationale for developing innovative energy-saving materials based on gypsum binders for buildings and structures with optimized carbon dioxide (CO2) emissions allows us to consider underburnt ash and slag mixtures as a promising technogenic product that allows us to comprehensively solve technological, economic and environmental problems in the construction industry. The study of the possibility of synthesizing promising mineral compositions based on underburnt products isolated from non-recyclable ash and slag mixtures (ASM) of coal-fired power plants ensures the development of a base of design and engineering solutions for buildings and facilities with rational energy consumption and optimized CO2 emissions using gypsum nanomaterials with unique properties. Materials and methods. In the study, technogenic carbon (underburning) was isolated from ash and slag mixtures by flotation enrichment using reagents (flotators). Results and discussions. The results of the study of energy-efficient gypsum composites based on a technogenic carbon modifier confirm its active participation in the processes of structure formation and crystallization of nanostructured building materials with high-tech characteristics. Conclusion. The research results obtained in the field of developing innovative, energy-efficient, cement-free building materials can contribute to an increase in the level of knowledge and the development of innovative approaches in construction materials science. These findings will be useful for subsequent implementation in the construction industry. The research topic is in line with the implementation of state programs, including the Strategy for Scientific and Technological Development of the Russian Federation.
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Статья научная
The use of concrete in building allows obtaining reliable and long-lasting operation of buildings, but such conditions require concrete with specified characteristics. Today hardly one can produce a concrete structural mix of high quality without any additives. To control actively the structure and properties of a concrete mix and concrete, along with chemical additives, mineral additives are used. The mineral additives are the powders of various mineral nature, obtained from natural or man-made raw materials: ground slag, rocks, etc. The article introduces the method of obtaining a mineral additive for a structural mix, in particularly for concrete. Qualitative characteristics of the additive obtained were studied as follows: the index of the degree of grinding to be equal to 1, standard consistency (normal density) – (180±5) mm with a mass ratio of «additive: water») – 100: 70, setting time – beginning 20 min, water absorption 0.27%, water content 9.65%, the proportion of insoluble residue in hydrochloric acid solution is 1.70%. Implementation of the additive in the concrete composition has shown that the quality of the product does not fall, and the actual strength is 250.7 kgf/cm2, which is slightly higher than the strength of the concrete sample without an additive. It was determined that the quality of concrete products with a mineral additive corresponds to GOST as follows: density 1775 kg/m3; mass humidity 0.3%; volume humidity 0.5%. The introduction of a structural mix will significantly improve the properties of a concrete structural mix and will also reduce the fuel resources consumption for production of the concrete structural mix, products and constructions of its basis.
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Статья научная
Introduction. The elaboration of foamed eco-friendly gypsum nanocomposites with low specific gravity, high thermal insulation, operational and technical and economic characteristics remains an urgent task. Controlled hardening of gypsum foam nanoassemblers using dry foaming agents is a promising direction in the technology of production of heat-insulating building materials. Methods and materials. The production of a foam gypsum composition was carried out in an ejector-turbulent mixer by mixing a gypsum nanobinder with functional foaming nanoadditives. Building gypsum G5 BII was used as a binder in the work; porization of gypsum compositions was carried out using an adsorbed foaming agent PBNS. Results. The transformation of liquid-phase foaming agents into solid-phase ones by binding water allows the production of gypsum foam compositions from dry mixtures, which gives high dosing accuracy, a good degree of homogenization of components and stable characteristics of foamed gypsum nanocompositions. In production conditions, a one-storey small-sized pavilion was built using a pilot 3D printer AMT S1160, in which vertical enclosing structures are filled with foamed heat-insulating nanostructured foam gypsum. Monolithic foam gypsum nanomaterial with a density of 300–400 kg/m3 was used for insulation and sound insulation of attic floors during the overhaul of the historic building of the Veterans Hospital in Ufa. Discussion. The elaboration of technology for obtaining foam gypsum from dry mixtures is based on the advantage of manufacturing and using thermal insulation nanocompositions, which allows for significant punctuality of dosing and stable characteristics of foam gypsum building materials. Surfactants have a significant effect on the kinetics of the structure formation of the foam gypsum nanocomposition and slow down the coalescence of air bubbles. Conclusions. Nanoporous foam gypsum concrete, obtained as a result of controlled hardening, with a density of 400 kg/m3 has a thermal conductivity of 0.12 W/(m•ºС) and a compressive strength of 1.4 MPa. The compressive strength of foamed foam gypsum using a dry foaming agent on sorbents is 17% higher than the strength of a heat-insulating nanomaterial prepared using traditional technology.
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Статья
Introduction. The most effective binding agents in wood-polymer composites based on polyvinyl chloride are carboncontaining nanostructures, which improve the electrical, physical-mechanical, rheological properties, as well as the structure and durability of the composites. Their main disadvantage is a high degree of particle aggregation, which makes it difficult to mix and process them in polymer compositions. In this regard, an urgent task is to search for such carbon nanomodifiers that would have a low degree of aggregation and low cost. Methods and materials. The paper studies the effectiveness of mechanically activated petroleum cokes as binding agents in building wood-polymer composites based on polyvinyl chloride. Mechanical activation leads to the functionalization of carbon particles of coke with the formation of oxygen-containing groups on the surface. The effect of various amounts of coke (up to 10% of the mass of wood flour) is considered and the relationship between the nature of coke and their concentration in the polymer compositions with the main technological (melt flow) and operational (tensile and bending strength, high elasticity modulus, hardness, water absorption and thermal stability) indicators and supramolecular structure of woodpolymer composites has been identified. Results and discussion. With the introduction of cokes, a high degree of orientation of the supramolecular structures of the composites in the direction of extrusion of the samples is observed, which leads to an increase in the breaking strength and bending strength, as well as the high elasticity modulus. The optimal concentration of additives was determined from 0.1 to 5%. In relation to wood flour, the amount of which in the wood-polymer composition is 50 mass parts per 100 mass parts PVC. Conclusion. The introduction of mechanically activated petroleum cokes as binding agents in wood-polymer composites based on polyvinyl chloride has been carried out. Mechanical activation made it possible to reduce the aggregation of coke particles into larger agglomerates, which makes it possible to efficiently introduce the nanomodifier in dry form and to exclude the introduction of nanomodifier in the form of aqueous dispersions, which is a rather energy-intensive production operation.
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Статья научная
Introduction. In the context of the need to improve energy efficiency and decarbonize cement production, the development of technologies using natural active mineral additives is becoming increasingly relevant. This article examines the use of opoka and diatomite as active additives for producing Portland cement, which allows the clinker content to be reduced by up to 50% while maintaining the operational properties of the cement. Methods and Materials. The research was conducted using electron microscopy, X-ray phase analysis, and energy-dispersive microanalysis. The study analyzed the composition of clinker from SAS-Tobe Technologies, gypsum from the Bagalin deposit, slags from the Novo-Dzhambul Phosphorus Plant, opoka from the Turkestan-Urangay deposit, and diatomite from the Utesai deposit. Physicochemical tests were carried out in the “SAPA” laboratories and at the LLP “SAS-Tobe Technologies” plant. Results and Discussion. The results of the study showed that the addition of opoka and diatomite in a quantity of 15% accelerates mineral formation processes due to the formation of a liquid clinker phase at lower temperatures. This reduces the firing temperature by 100–150 °C, leading to lower energy consumption and improved thermodynamic processes in clinker formation. Conclusion. The introduction of natural mineral additives in Portland cement production reduces clinker content by up to 50%, contributing to energy and resource savings without compromising cement quality. The research results confirm the potential of using opoka and diatomite for decarbonizing the cement industry and increasing its energy efficiency.
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Energy resource efficient designs of small-sized water circulating cooling devices
Статья научная
To use natural sources in rational way, plantsof continuous cooling of closed systems of recycling water supply are used. The paper presents designs of small-sized devices for recycling water cooling which are energy resource effective due to twisted motion of air flow, moving countercurrent to the cooled water. Heat and mass transfer is a nanotechnological process that occurs at the intermolecular level. Methods and materials. Countercurrent mini cooling towers are widely used in all industries, but there are some disadvantages, the main of which is the insufficient interaction time of the moving phases. Screw motion of air flow is created by the tangential supply of cooling air in the bottom part of cylindrical small-sized cooling tower. The rate of rotary motion decreases as air flow moves up in cooling towers, and vertical parameter of the rate – increases. Such scheme of the air flow motionmakes it possible to decrease average vertical parameter of the rate and to increase phases contact time. Laboratory research. To determine the technological and hydroaerothermal characteristics, as well as to estimate the efficiency of cooling recycled water, and to carry out mass-heat exchange at the intermolecular stagean experimental facility of small-sized cooling tower with twisted air flow has been developed. Conclusions. In accordance with the exponential law it is shown that the rotational component decreases at increasing height, and in accordance with the power law the vertical component increases component with the exponent ~1,79. It is determined that moisture content x and air temperature tv in the volume of the height of the sprinkler varies according to a power law, in particular for a screw cooling tower proportionally x ~ h0,83, tв ~ h1,25. It was determined that the coefficients of mass transfer βxv and heat transfer αv of a mini cooling tower with twisted air flow at the intermolecular level with equal irrigation densities are 20% higher than the coefficients of a mini cooling tower with counter-current flow. Also it has been determined experimentally a dependence of aerodynamics resistance coefficient of the twisted irrigator of the cooling tower on criterium Refor air flow, and it was determined that it decreases like Re–K2 as the exponent K2 varies in the range 0.114÷0.193 depending on the irrigation density.
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Epoxy composites modified with coal tar
Статья научная
Introduction. Despite significant progress in the creation of high quality polymer composites with a unique combination of key indicators, some issues in this area have not been fully studied. This paper presents the results of research on the structure of materials based on epoxy-coal binder and analysis of physical and mechanical properties at the microstructure level, which are influenced by various factors: the quantitative content of modifying additives and various fillers, the degree of particle dispersion, their size and shape. It has been revealed that nanoscale particles are one of the potential modifiers of the microstructure of composites. Materials and methods. As part of the experiment, composites were studied, in which ED-16 epoxy resin modified with coal tar was used as the main binder. Polyethylene polyamine served as a hardener. Reduction of viscosity and plasticization of compositions was achieved through the use of gasoline, acetone, turpentine, white spirit, dibutylphthalate, etc. Quartz sand, fine powders of brick, marble, glass, limestone, and in addition, Portland cement were used as fillers. Two nano additives were used: carbon black and carbon nanotubes. Standard techniques were used to reveal the mechanical characteristics. Physicochemical investigations were carried out by IR spectroscopy. Tests of samples for fungus resistance and fungicidal properties were carried out in accordance with the State Standard (SS) 9049-91. Results. The results of composite tests are presented in the form of spectrograms, graphical dependencies, and tabular data. Discussion. The results of analyzing the obtained experimental data are presented. The optimum content of polyethylene polyamine for curing of epoxy-coal compositions has been determined. The following has been established: the physical and mechanical properties of composites depend to a great extent on the nature of the solvent, and changes in wide ranges have been recorded. It has been determined that the properties of composite materials are seriously influenced by the dispersity and quantitative content of the filler. The expediency of nano-additives application in epoxy compositions has been revealed. In the course of the experiment the dependences of the change of chemical resistance and biological resistance of composites on the type and quantitative content of the modifying additive, on the nature of the filler were determined. Conclusions. Modified epoxy-coal composites with the use of multilevel fillers and additives have been developed. This makes it possible to increase the strength, increase the deformability and crack resistance of building materials composites for operation, which is very important under the influence of chemical and biological aggressive environment.
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