Nanotechnologies in Construction: A Scientific Internet-Journal @nanobuild-en
Статьи журнала - Nanotechnologies in Construction: A Scientific Internet-Journal
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The electronic edition «Nanotechnologies in construction: A Scientific Internet-Journal»
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The electronic edition «Nanotechnologies in construction: A Scientific Internet-Journal»
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The electronic edition «Nanotechnologies in construction: A Scientific Internet-Journal»
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The electronic edition «Nanotechnologies in construction: A Scientific Internet-Journal»
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The electronic edition «Nanotechnologies in construction: A Scientific Internet-Journal»
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The formation of the sol-gel nanostructures of road bitumen by selecting chemical group composition
Статья научная
The studies of paving bitumen chemical composition and physicochemical properties produced by compounding deeply oxidized bitumen, tar and vacuum gas-oil of different hydrocarbon composition are carried out. The bitumen is marked to have the optimal complex of properties if the best chemical group composition of three main elements bitumen binding agents – oils, resins and asphaltenes - is formed. That provides the best structure of bitumen oildisperse system. The object of the research is the selection of compounded paving bitumen chemical group composition that provides the formation of bitumen nanodisperse system as «sol-gel» which quality metrics match the requirements of the new State Standard 33133-2014 «Petroleum paving viscous bitumen». The analysis of the research results makes it possible to determine the optimal chemical group composition of compounded bitumen that meets standard requirements by physicochemical properties. It has been determined that the higher the bitumen dispersion is, the more plastic properties it has. In addition, the bitumen ability to thermal-oxidative processes of deterioration decreases. The value range of bitumen dispersion and the most optimal values of asphaltenes ratio to the amount of oils and resins for bitumen grade BND 100/130 and for bitumen grade BND 70/100 were found. This amount of oils and resins for referred bitumen grades provide production of nanostructured bitumen as «sol-gel». It is shown that when processing tar of different chemical composition the optimal chemical group composition of finished product can be formed by compounding. That rises probability that the end product will fit to the new State Standard 33133-2014. The represented results of the research can be used in fabrication as the modern laboratories of the oil-refining enterprises can determine quite efficiently the chemical composition of oil products used in compounding processes in bitumen binding agents production.
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The influence of nano-additives in the synthesis of eco-friendly polyester plasticizers
Статья научная
Plasticized polymer materials are widely used in all spheres of human life. The most common plasticizers are aromatic compounds-esters of o-phthalic acid. However, their use was limited in accordance with the EU Directive REACH (2009) due to possible toxicity, which contributed to the development of new non-toxic alternatives, which include polyester plasticizers. Polyester plasticizers are classified as special purpose plasticizers. Due to the wide variety of starting materials and the ability to vary the size of the molecule, a wide range of plasticizers can be synthesized. These are mainly polyesters of polyatomic alcohols esterified with dibasic acids and modified with monocarboxylic acid or aliphatic alcohol. Polyesters-based plasticizers contribute to the production of PVC compositions with improved properties such as low volatility, resistance to extraction, excellent flexibility, wear resistance, UV resistance and heat resistance. Also, such plasticizers exhibit an excellent non-sweating property of plastics. This paper describes a method for preparing a polyester compound propylene glycol adipate modified with cyclohexanecarboxylic acid, proposed as a plasticizer of polyvinyl chloride. Conditions of its production with maximum output are given. Physical and chemical properties of the resulting compound were studied. The formulation of PVC-composition on the basis of the received polyester plasticizer is offered. The results of tests of PVC plastic according to state standard 5960-72 are presented. It is shown that the use of propylene adipate modified with cyclohexanecarboxylic acid provides a plasticizing efficiency as high as DOP, while having a reduced migration. This fact allows us to use the developed polyester plasticizer as a non-toxic alternative to industrial PVC plasticizers. It has been found that the use of calcium adipate nano quantities in the production of propylene glycol adipate increases the yield of the desired ester and improves the physical and mechanical properties of PVC plastic.
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Статья научная
Introduction. Drilling and reconstruction of oil and gas wells are key stages in the development of hydrocarbon fields. One of the most significant technological elements that greatly influences the efficiency of the process is the drilling fluid (DF). It performs many functions, including cooling and lubrication of rock-cutting and special tools, bottomhole cleaning from drilled rock, maintaining well wall stability and many others. In recent years, special attention has been paid to the use of nanomaterials in the DF drilling fluid composition. Nanoscale additives can significantly improve technological properties of water-based muds, increase their efficiency and reduce drilling costs. Methods and Materials. The influence of additives on general technological parameters of Clay-Free Drilling Mud (CFDM) was evaluated. Special attention was paid to revealing the influence of the developed experimental additives on the friction coefficient and antifriction properties of (CFDM), which were determined using modified friction machine AI5018. Results and discussion. This study focuses on the investigation of the impact of nano-additives on the technical properties of water-based mud (WBs) and their effectiveness for drilling and well reconstruction. In the course of the work, comprehensive laboratory studies have been carried out to evaluate the effect of nano-additives of different nature, such as nano-graphite and nano-carbon materials, on the lubricating properties of water-based mud (WBs), which helps to reduce the wear of drilling equipment, increase the mechanical speed of drilling and, as a consequence, reduce the time and financial costs of well construction and re-construction. Conclusion. The introduction of nano-additives allowed significantly in improving the technological properties of drilling fluid DF. The obtained results can be used to improve the compositions of solutions based on the use of nanomaterials, which will increase the efficiency and reliability of well drilling processes.
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The inventions in nanotechnologies as practical solutions. Part I
Статья научная
A brief review of patents is given. The research performed by scientists, engineers and specialists in the area of nanotechnologies and nanomaterials result in increased efficiency of construction, housing sector and adjacent fields of economy. The invention «A method of introduction of single-shell and/or double-shell and/or multi-shell carbon nanotubes in adhesive additive composition for asphalt coating and application of single-shell and/or double-shell and/or multi-shell carbon nanotubes as a part of adhesive additive composition» refers to construction, in particular, to the materials used in road, airdrome and civil construction. Concentration (content) of single-shell and/or double-shell and/or multi-shell carbon nanotubes varies from 0,01% to 15% of volume of asphalt covering. The invention «A method to produce nanocomposite material» based on aluminium refers to powder metallurgy, in particular to production of metal and carbon composite materials and articles of them in different shapes and can be used in auto industry, shipbuilding, aircraft engineering and instrument manufacture and other areas. The invention «A method of low temperature application of nanocrystal coating of alpha-oxide aluminium» refers to method of production nanocrystal coating of alpha-oxide aluminium with high rate under low temperature. Coatings of aluminium oxide are characterized by high thermal resistance, chemical inaction, hardness, compression resistance, heat-insulation capacity and is widely used for protection the products exposed to high temperatures and aggressive environments. The specialists can also be interested in the following inventions in the area of nanotechnologies: device and method for production of powder materials based on nano- and microparticles through electric explosion of wire; vacuum machine for application of nanostructured coating made of material with shape memory effect on the detail surface; hierarchically reinforced heteromodular extrudable solid lubricant nanocomposite based on UHMW PE and a method to produce it; hydrogen-accumulating materials and a method to produce them et al.
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The inventions in nanotechnologies as practical solutions. Part II
Статья научная
A brief review of patents is given. The research performed by scientists, engineers and specialists in the area of nanotechnologies and nanomaterials result in increased efficiency of construction, housing sector and adjacent fields of economy. For example, invention «Elastic conductive film on the basis of silver nanoparticles», according to experts, is of great interest for science and industry. This new type of electronics potentially can be applied in many fields, such as elastic sensor skin for robot devices, portable electronics for functional clothes, elastic sensors and flexible electronic displays. Elasticity of materials is highly needed in electronic devices that contact the human body or curved surfaces. Elastic conductive film contains many annealed nanoparticles of conductive metal, in particular silver, applied on substrate. Adhesion of silver film is of great quality: when abrasion test was finished, there were no defects or there were slight defects. The specialists can also be interested in the following inventions in the area of nanotechnologies: a method to introduce single-wall and/or two-wall and/or multi-wall carbon nanotubes in composition of adhesive additives for asphalt coating and application of single-wall and/or two-wall and/or multi-wall carbon nanotubes in composition of adhesive additives; welding wire with nanocomposite coating for welding of high-tensile steel; A method to produce nanocomposite material based on aluminium; sewage treatment system with nanomodified natural sorbents et al.
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The inventions in nanotechnologies as practical solutions. Part III
Статья научная
A brief review of patents is given. The research performed by scientists, engineers and specialists in the area of nanotechnologies and nanomaterials resulted in increased efficiency of construction, housing sector and adjacent fields of economy. For example, the invention «Construction structural element» refers to the field of construction. The building element is made of a cured mixture containing the following components, wt. %: dispersed foamglass – 60–85; 25–30% alumina solution in phosphoric acid – 13–34; basalt microfiber – 2–6; fulleroid type carbon toroid-like nanoparticles (fractions from 15 to 150 nm) – 0.009–0005. The dispersed foamglass is made in the form of foamed glass beads, on the surface of which a layer of polyparaxilylene 2–5 microns thick is applied. The mixture is cured at a temperature of 160–180оC. The technical result is increased strength, toughness, crack resistance and durability at low density, that is important when building objects, for example, to create internal walls and cellular partitions in rooms. The specialists can also be interested in the following inventions in the area of nanotechnologies: composite reinforcement, a method of manufacturing composite powder material from alumina carbon nanotubes; the method of plasma deposition of nanostructured heat-shielding coating; the method of degassing tungsten nanopowder; method to produce mixtures of highly dispersed heterophase powders based on boron carbide, etc.
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The inventions in nanotechnologies as practical solutions. Part IV
Статья научная
A brief review of patents is given. The research performed by scientists, engineers and specialists in the area of nanotechnologies and nanomaterials resulted in increased efficiency of construction, housing sector and adjacent fields of economy. For example, the invention «Carbon ceramic fiber-reinforced composite material and method for its production» refers to a class of carbon-based composite materials of heat-shielding, structural, chemical-resistant purposes, can be used under static and dynamic loads when heated to 2000оC in an oxidizing environment (aerospace engineering, construction facilities for special purposes, high-temperature electrothermal equipment, equipment for nuclear reactors, etc.). The technical result of the invention is the strength of the composite increased up to 40% in terms of flexural strength and twice in terms of compressive strength. The specialists can also be interested in the following inventions in the area of nanotechnologies: building construction elements; a method for synthesizing a composite carbon material with metal nanoparticles with transferring a part of their electron density to a carbon matrix; a method of manufacturing marker of fuel and lubricants; wastewater treatment system with nano-modified natural sorbents; nanocrystal, hydrosol of nanocrystalline cellulose and method for producing it; a method for producing membranes for ultrafiltration of aqueous media; a method of obtaining transparent ceramics of yttrium-aluminum garnet; method and device for atomic emission spectral analysis of nanoobjects, etc.
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The inventions in nanotechnologies as practical solutions. Part V
Статья научная
A brief review of patents is given. The research performed by scientists, engineers and specialists in the area of nanotechnologies and nanomaterials resulted in increased efficiency of construction, housing sector and adjacent fields of economy. For example, the invention «A method to produce fireproof wood-polymer composites on the basis of secondary polyolefine» can be used in construction, car industry, shipbuilding, machine manufacturing, furniture trade and other industries. The method includes following stages: drying of composite components, mixing and heat forming of them by means of extrusion in extrusion Co- Kneader plant under treatment temperature120оС–150оС and conveyor screw rotation speed 350–450 RPM with further granulation. The obtained fire-resistant wood-polymer composite possesses high performance characteristics. The specialists can also be interested in the following inventions in the area of nanotechnologies: a method to produce strengthened nanocomposite with additional properties, anodic material for lithium-ion battery and a method to produce it, a method to rise breaking strength of composite material by preliminary impregnation of carbon fibers with carbon nanotubes, a method to produce carbon metal-containing nanostructures, a method to produce volume microscale structures from nanoparticles and a device to perform it, antistatic floor coating with carbon nanotubes and other.
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Статья научная
This study presents an investigation of the effects of high temperature on the thermal and microstructural properties of cement mortars modified with nanosilica. In the first stage of the research, the effects of nanosilica (NS) and silica fume (SF) on the hydration and compressive strength of cementitious composites were compared. In the second stage, four different types of cement mortars, containing an optimal dosage of NS, were produced. Two of them contained a normal weight aggregate (quartz or limestone), whilst two contained a heavy weight aggregate (barite or magnetite). Specimens without NS were produced for control purposes. The specimens were exposed to 300, 450, 600 and 800°C, with their post-heating properties – including thermal conductivity, specific heat, solvent absorption and cracking behavior – analyzed. The results show that NS exhibits significantly higher reactivity with cement than SF. NS accelerates the cement hydration process and contributes more significantly to the 28 and 365 day compressive strength of mortar, as compared to SF. The incorporation of NS in a composite substantially decreases the amount of CH in the mixture and leads to the production of additional C–S–H gel phase, which improves microstructure. The study also shows that NS contributes to a decrement in the thermal conductivity and density of mortar, both prior to and after heating. The incorporation of NS has a beneficial effect on decreasing the deterioration rate of mortars after heating, by decreasing absorption rate and the amount of cracks in in them.
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Статья научная
This study presents an investigation of the effects of high temperature on the thermal and microstructural properties of cement mortars modified with nanosilica. In the first stage of the research, the effects of nanosilica (NS) and silica fume (SF) on the hydration and compressive strength of cementitious composites were compared. In the second stage, four different types of cement mortars, containing an optimal dosage of NS, were produced. Two of them contained a normal weight aggregate (quartz or limestone), whilst two contained a heavy weight aggregate (barite or magnetite). Specimens without NS were produced for control purposes. The specimens were exposed to 300, 450, 600 and 800°C, with their post-heating properties – including thermal conductivity, specific heat, solvent absorption and cracking behavior – analyzed. The results show that NS exhibits significantly higher reactivity with cement than SF. NS accelerates the cement hydration process and contributes more significantly to the 28 and 365 day compressive strength of mortar, as compared to SF. The incorporation of NS in a composite substantially decreases the amount of CH in the mixture and leads to the production of additional C–S–H gel phase, which improves microstructure. The study also shows that NS contributes to a decrement in the thermal conductivity and density of mortar, both prior to and after heating. The incorporation of NS has a beneficial effect on decreasing the deterioration rate of mortars after heating, by decreasing absorption rate and the amount of cracks in in them.
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