wyświetlamy 1000 najlepszych wyników Pomoc
Wyniki wyszukiwania dla: THERMAL PROPERTIES
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Correction: Simultaneously improving the thermal stability, flame retardancy and mechanical properties of polyethylene by the combination of graphene with carbon black
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Combination of fumed silica with carbon black for simultaneously improving the thermal stability, flame retardancy and mechanical properties of polyethylene
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Structural, thermal and physico-mechanical properties of polyurethane/brewers’ spent grain composite foams modified with ground tire rubber
PublikacjaIn this work, brewers’ spent grain (BSG) and ground tire rubber (GTR) waste fillers were applied as low-cost reinforcement phase in rigid polyurethane foam (PUR). PUR/BSG/GTR composites were prepared by a single step method, using polyglycerol as partial substitute of commercially available petrochemical polyols. Foaming parameters, chemical structure, dynamic mechanical properties, thermal stability, physico-mechanical properties...
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Effect of Variation of Hard Segment Content and Graphene-Based Nanofiller Concentration on Morphological, Thermal, and Mechanical Properties of Polyurethane Nanocomposites
PublikacjaThis study describes the development of a new class of high-performance polyurethane elastomer nanocomposites containing reduced graphene oxide (RGO) or graphene nanoplatelets (GNP). Two types of polyurethane elastomers with different contents of hard segments (HS) were used as a polymer matrix. The developed nanocomposites were characterized by thermal analysis (DSC, TG), dynamic mechanical testing (DMA), hardness testing, mechanical...
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The influence of thermal treatment on electrocatalytic properties of Mn-Co nanofilms on nickel foam toward oxygen evolution reaction activity
PublikacjaThis work evaluates electrodeposited and differently treated Mn-Co catalysts for their oxygen evolution reaction activity. Catalysts are evaluated in the as-deposited and heat treated state: after 350 C and 600 C. Results show that the highest electrochemical activity is obtained for the as-deposited Mn-Co oxyhydroxide, which possibly possess a layered double hydroxide structure. After the heat treatment process, especially after...
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Dynamic mechanical properties and thermal degradation process of the compositions obtainedfrom unsaturated poly(ester urethanes) cross-linked with styrene
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Thermal and mechanical properties of polyamide 12/modified carbon nanotubes composites prepared via the in situ ring-opening polymerization
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Nanosized carbon black as synergist in PP/POE-MA/IFR system for simultaneously improving thermal, electrical and mechanical properties
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The influence of different flame retardants on thermal stability, mechanical and physical properties of rigid polyurethane foams blown with n-pentane
PublikacjaW artykule opisano wpływ klasycznych uniepalniaczy na właściwości sztywnych pianek poliuretanowych. Opisano 7 układów piankowych oraz wyniki charakterystyki fizyczno-mechanicznej oraz stabilności termicznej.
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Rheological properties, oxidative and thermal stability, and potential application of biopolyols prepared via two-step process from crude glycerol
PublikacjaIn this work, previously synthesized biopolyols were analyzed in terms of their rheological and thermal properties, very important from the technological point of view. For better evaluation of performed synthesis, the influence of its time and temperature on the properties of biopolyols was determined. In the end, obtained materials were used to prepare rigid polyurethane-polyisocyanurate (PUR-PIR) foams, to evaluate their potential...
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Effect of ionic liquids on the structural, thermal, andin vitrodegradation properties of poly(ε-caprolactone) synthesized in the presence ofCandida antarcticalipase B
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Dynamic mechanical properties and thermal degradation process of the compositions obtained from unsaturated poly(ester urethanes) cross-linked with styrene
PublikacjaW pracy przedstawiono właściwości dynamiczno-mechaniczne oraz stabilność termiczną poli(estro uretanów) sieciowanych styrenem. Badane poli(estro uretany) syntetyzowano z nienasyconych oligomeroli opartych na cis-2-buten-1,4-diolu oraz 4,4`-diizocyjanianie difenylometanu. Wyniki badań dynamicznych właściwości mechanicznych otrzymanych poliuretanów potwierdziły separację fazową uzyskanych kompozycji. W pracy przedstawiono również...
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Thermal, electrical, and magnetic properties of Fe2O3–PbO–SiO2 glass prepared by traditional melt-quenching and twin roller fast-cooling methods
PublikacjaIn this study, Fe–Pb–Si oxide glasses containing between 12.5 and 17.5 mol% Fe2O3 were prepared using two different methods comprising traditional melt-quenching and twin roller fast-cooling techniques. The topography and structure of the materials obtained were characterized by X-ray powder diffraction and scanning electron microscopy. All of the materials were found to be amorphous. The topography of most of the glasses comprised...
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Właściwości termoizolacyjne kompozytu wapienno-cementowego z udziałem paździerzy konopnych=Thermal insulation properties of the lime-cement composite with hemp shives
PublikacjaPrzedstawiono wyniki badań kompozytów wykonanych na bazie wapna budowlanego, cementu i dolomitu - spoiwa wiążącego z udziałem paździerzy konopi. Określono ich podstawowe właściwości, tj.: gęstość objętościową, współczynnik przewodzenia ciepła oraz wytrzymałości na ściskanie. Otrzymane wyniki dowodzą, że wytworzone kompozyty wapienno-cementowe z udziałem paździerzy konopnych są lekkie i charakteryzują się niskim współczynnikiem...
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Influence of chemical structure on physicochemical properties and thermal decomposition of the fully bio-based poly(propylene succinate-co-butylene succinate)s
PublikacjaIn this work, two polyesters and four copolyesters were studied. All materials were synthesized to obtain the monomers dedicated for thermoplastic polyurethane elastomers. For this type of PUR, the monomers should characterize by appropriate selected physicochemical properties and macromolecular structure distribution, which depends on synthesis conditions. The study of chemical structure with extensive and knowledgeable analysis...
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Characterization of volatile compounds, structural, thermal and physico-mechanical properties of cross-linked polyethylene foams degraded thermo-mechanically at variable times
PublikacjaWaste cross-linked polyethylene foam (wXLPE) was thermo-mechanically degraded at variable time using internal batch mixer. The progress of wXLPE degradation has been investigated by using a simultaneous thermogravimetric/differential scanning calorimetry analyzer coupled with Fourier transform infrared spectroscopy, swelling measurements, tensile tests and scanning electron microscopy. Volatile organic compounds generated during...
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High-temperature oxidation of the Crofer 22 H ferritic steel with Mn1.45Co1.45Fe0.1O4 and Mn1.5Co1.5O4 spinel coatings under thermal cycling conditions and its properties
PublikacjaThe aim of the presented study was to deposit protective-conducting Mn1.45Co1.45Fe0.1O4 and Mn1.5Co1.5O4 spinel coatings on the Crofer 22 H ferritic steel by means of electrophoresis and to evaluate their physicochemical properties after high-temperature oxidation under thermal cycling conditions. When the Crofer 22 H steel – whether uncoated or coated with the two spinels – was oxidized in 48-h cycles involving a temperature of...
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Physicochemical properties of Mn1.45Co1.45Cu0.1O4 spinel coating deposited on the Crofer 22 H ferritic steel and exposed to high-temperature oxidation under thermal cycling conditions
PublikacjaThe Crofer 22 H ferritic steel substrate was coated with an Mn1.45Co1.45Cu0.1O4 spinel by means of electrophoresis. After high-temperature oxidation under thermal cycling conditions, the physicochemical properties of the obtained system were evaluated. During 48-h cycles that involved heating the samples up to temperatures of either 750 or 800 °C, the oxidation kinetics of both coated and unmodified steel approximately obeyed...
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Reactive construction of catalytic carbonization system in PP/C60/Ni(OH)2 nanocomposites for simultaneously improving thermal stability, flame retardancy and mechanical properties
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Expanded graphite assistant construction of gradient-structured char layer in PBS/Mg(OH)2 composites for improving flame retardancy, thermal stability and mechanical properties
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Synthesis, structure characterization and thermal propertiesof [Zr<sub>6</sub>(μ<sub>3</sub>-O)<sub>4</sub>(μ<sub>3</sub>-OH)<sub>4</sub>(OOCCH<sub>2</sub><sup>t</sup>Bu)<sub>9</sub>(μ<sub>2</sub>-OH)<sub>3</sub>]<sub>2</sub>
PublikacjaTytułowy związek otrzymano w reakcji Zr(OiPr)4 z nadmiarem kwasu 3,3-dimetylobutyrowego. Rentgenowska analiza strukturalna została wykonana w temperaturze 103 i 153K. Struktury zawierają dimery podjednostek o wzorze: [Zr6(μ3-O)4(μ3-OH)4-(OOCCH2tBu)9] połączonych 6 mostkującymi grupami μ2-OH. Analiza zmiennotemperaturowych...
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Marek Pszczoła dr hab. inż.
OsobyI am a Faculty member (Department of Highway and Transportation Engineering) at the Faculty of Civil and Environmental Engineering, Gdansk University of Technology, Poland). My main research interests include: low-temperature properties of asphalt mixtures, low temperature cracking assessment of pavement structures, road materials properties, thermal stress analysis, design of pavement structures, airfield design and analysis....
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Application of nanofluids in thermal technologies
PublikacjaNanofluids it is a relatively new category of thermal fluids that can serve as coolants, both in single- and two phase systems. However application of nanofluids in industrial applications requires faultless their thermophysical properties. Existing models originally developed for liquid/solid particles mixtures (slurries) fail in case of nanofluids. Moreover correlations used to calcuate heat transfer coefficients of conventional...
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Mariusz Kaczmarek dr hab. inż.
OsobyReceived M.Sc., Eng. in Electronics in 1995 from Gdansk University of Technology, Ph.D. in Medical Electronics in 2003 and habilitation in Biocybernetics and Biomedical Engineering in 2017. He was an investigator in about 13 projects receiving a number of awards, including four best papers, practical innovations (7 medals and awards) and also the Andronicos G. Kantsios Award and Siemens Award. Main research activities: the issues...
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Thermal and Mechanical Behavior of Elastomers Incorporated with Thermoregulating Microcapsules
PublikacjaPolyurethane (PU) is one of the principal polymers in the global plastic market thanks to its versatility and continuous improvement. In this work, PU elastomeric materials having thermoregulating properties through the incorporation of microcapsules (mSD-(LDPE·EVA-RT27)) from low-density polyethylene and vinyl acetate containing paraffin®RT27 as PCM were produced. Elastomers were synthesized while varying the molar ratio [NCO]/[OH]...
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Thermal ablation modeling via bioheat equation
PublikacjaWe consider Pennes’ bioheat equation and discuss an implicit numerical scheme which has better stability properties than other approaches. Our discussion concerns Carthesian geometry problems, however it carries over to spherical geometry models and more complicated shapes.
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Impact of thermal loading into the structural performance of ships: A review
PublikacjaThe presented study reviews the recent advances done regarding the impact of thermal loading on the structural performance of ships. Firstly, the studies related to the mechanical and thermal properties of typical materials used in shipbuilding are outlined. Secondly, a brief introduction to the heat transfer analysis, Finite Element modelling and thermal stresses is provided. Finally, the review of papers dealing with the structural...
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Galerkin Finite Element Process for Entropy Production and Thermal Evaluation of Third-Grade Fluid Flow: A Thermal Case Study
Publikacja: A fluid’s moving class improves its heat transmission capability, as well as its rigidity, owing to multivariate molecule suspension. In this way, nanofluids are superior to common fluids. In this study, we evaluated the features of ease and heat transfer. Furthermore, we investigated permeable media, heat source, variable heat conductivity, and warm irradiation results. A mathematical technique known as the Galerkin finite element...
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Foamed Polyurethane Composites With Different Types of Ash – Morphological, Mechanical and Thermal Behavior Assessments
Publikacjancorporation of two types of ash particles into flexible polyurethane foams has been investigated, wood ash from gasification process and fly ash resulting from coal burning in power plant. Samples were modified with 5, 10 and 15 wt% of fillers. Structure, mechanical and thermal properties of obtained foams were investigated. Incorporation of both types of ash particles resulted in materials showing...
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Dariusz Mikielewicz prof. dr hab. inż.
OsobyDariusz Mikielewicz – urodził się 6 lutego 1967 roku w Gdańsku, w 1985r. zdał pomyślnie egzaminy wstępne na Wydział Budowy Maszyn Politechniki Gdańskiej, który ukończył z wynikiem bardzo dobrym w 1990 roku na specjalności Maszyny i Urządzenia Energetyczne. Zainteresowania pracą naukową skłoniły go do podjęcia badań na University of Manchester na wydziale mechanicznym i energetyki jądrowej (Mechanical and Nuclear Engineering Department)...
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Molecular Dynamics simulations of thermal conductivity of penta-graphene
PublikacjaThe thermal conductivity of penta-graphene (PG), a new two dimensional carbon allotrope and its dependence on temperature, strain, and direction are studied in this paper. The thermal conductivity of PG is investigated using a non-equilibrium molecular dynamics simulation (NEMD) with the Two Region Method by applying the optimized Tersoff interatomic potential. Our study shows that the thermal conductivity of PG (determined for...
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Preliminary Investigation on Auto-Thermal Extrusion of Ground Tire Rubber
PublikacjaGround tire rubber (GTR) was processed using an auto-thermal extrusion as a prerequisite to green reclaiming of waste rubbers. The reclaimed GTR underwent a series of tests: thermogravimetric analysis combined with Fourier-transform infrared spectroscopy (TGA-FTIR), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), and static headspace and gas chromatography-mass spectrometry (SHS-GC-MS) in order...
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Thermal ablation modeling via the bioheat equation and its numerical treatment
PublikacjaThe phenomenon of thermal ablation is described by Pennes’ bioheat equation. This model is based on Newton’s law of cooling. Many approximate methods have been considered because of the importance of this issue. We propose an implicit numerical scheme which has better stability properties than other approaches.
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Processing, mechanical and thermal behavior assessments of polycaprolactone/agricultural wastes biocomposites
PublikacjaIn this paper, brewer’s spent grain (BSG) was applied as potential lignocellulose biofiller in biocompos-ites based on polycaprolactone (PCL). The PCL/BSG biocomposites filled with varying content of biofillerswere prepared via low-temperature melt-compounding. These conditions allow limiting thermal degra-dation of used biofillers during processing. The influence of biofiller content (ranging from 25 to 200parts by weight on 100...
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Modification of thermal and rheological characteristics of bitumen by waste PET/GTR blends
PublikacjaWaste poly(ethylene terephthalate) (wPET)/ground tire rubber (GTR) blends with variable compositions were applied as low-cost modifiers into bitumen and their performance has been evaluated via morphological, thermal and rheological analyses. Depending on the weight ratio of wPET/GTR, dispersion of single/composite domains of waste polymers in the bitumen has promoted the interaction between bitumen and blend components. Fourier...
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TESTING CONTRACTION AND THERMAL EXPANSION COEFFICIENT OF CONSTRUCTION AND MOULDING POLYMER COMPOSITES
PublikacjaThe paper presents results of systematic tests of contraction and thermal expansion coefficients of materials based on polymer composites. The information on the above material properties is essential both at the design stage and during the use of finished products. Components for the samples were selected in such a way as to represent typical materials used for production of construction and moulding elements. The performed tests...
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Evaluation of thermal cracking probability for asphalt concretes with high percentage of RAP
PublikacjaThe paper presents determination of the probability of thermal cracking of asphalt mixtures with different reclaimed asphalt pavement (RAP) content on the basis of laboratory tests and analytical evaluation using thermal stress development method. Probability was evaluated taking into consideration: the type and gradation of the mixture and the quality and content of RAP. Thermal stresses were determined using two models: elastic and...
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About Unusual Diffraction and Thermal Self-Action of Magnetosonic Beam
PublikacjaThe dynamics of slightly diverging two-dimensional beams whose direction forms a constant angle θ with the equilibrium straight magnetic strength is considered. The approximate dispersion relations and corresponding links which specify hydrodynamic perturbations in confined beams are derived. The study is dedicated to the diffraction of a magnetosonic beam and nonlinear thermal self-action of a beam in a thermoconducting gaseous plasma....
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On thermal stability of piezo-flexomagnetic microbeams considering different temperature distributions
PublikacjaBy relying on the Euler–Bernoulli beam model and energy variational formula, we indicate critical temperature causes in the buckling of piezo-flexomagnetic microscale beams. The corresponding size-dependent approach is underlying as a second strain gradient theory. Small deformations of elastic solids are assessed, and the mathematical discussion is linear. Regardless of the pyromagnetic effects, the thermal loading of the thermal...
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Influence of type of material on performance of hydraulic components in thermal shock conditions
PublikacjaDuring the start-up of a hydraulic system in low ambient temperatures an incorrect operation may occur. The principles and conditions of safely operating hydraulic driven machines and devices are essential to designers and operators. For this reason the author of this article has conducted a series of tests on hydraulic components and systems in thermal shock conditions (cooled-down components were supplied with hot working medium)....
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Experimental Study on Dynamics of Wooden House Wall Panels with Different Thermal Isolation
PublikacjaWood frame buildings are very popular in regions that are exposed to different dynamic excitations including earthquakes. Therefore, their seismic resistance is really important in order to prevent structural damages and human losses. The aim of the present paper is to show the results of experimental tests focused on the dynamic response of wall panels of a wooden frame building with thermal isolation made of mineral wool and...
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Modification of microporous polyurethane elastomers with different types of ash—morphological, mechanical, and thermal studies
PublikacjaIncorporation of wood ash particles from wood gasification into microporous polyurethane elastomers has been investigated and compared to addition of commercially available microspheres resulting from coal burning. Samples were modified with 3 and 6 wt% of fillers. Structure, mechanical, and thermal properties of obtained elastomers were investigated. Incorporation of both types of ash particles decreased the density of polyurethanes...
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Effect of double thermal and electrochemical oxidation on titanium alloys for medical applications
PublikacjaThe research focuses on the development and characterization of innovative thin hybrid oxide coatings obtained in subsequent processes of thermal (TO) and electrochemical (EO) oxidation. Four different surface modifications were investigated and the microstructure was determined, the mechanical, chemical and biological properties of the Ti-13Nb-13Zr alloy were assessed using scanning electron microscopy, X-ray dispersion analysis,...
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Phase change thermal energy storage – the experience of the materials preparation for the specific applications.
PublikacjaThermal energy storage and temperature stabilization is very important in many engineering applications. There are three kinds of thermal energy storage: sensible heat, latent heat and reversible chemical reaction heat. Phase change materials (PCM) absorb, store and release large amounts of energy in the form of latent heat, at constant temperature, called the transition temperature. Many innovative applications could be found...
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Super-resolved Thermal Imagery for High-accuracy Facial Areas Detection and Analysis
PublikacjaIn this study, we evaluate various Convolutional Neural Networks based Super-Resolution (SR) models to improve facial areas detection in thermal images. In particular, we analyze the influence of selected spatiotemporal properties of thermal image sequences on detection accuracy. For this purpose, a thermal face database was acquired for 40 volunteers. Contrary to most of existing thermal databases of faces, we publish our dataset...
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Implementation of the Boundary Element Method to Two-Dimensional Heat Transfer with Thermal Bridge Effects
PublikacjaThe work presents an application of the boundary element method applied to a two-dimensional conductive heat transfer. The algorithm of the method is explained and its advantages are outlined. Green's function as a fundamental solution for Poisson's equation in two dimensions was used and the direct approach was applied. The presented results concern building construction elements as typical cases of thermal bridges. Some properties...
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Polyurethane/Silane-Functionalized ZrO2 Nanocomposite Powder Coatings: Thermal Degradation Kinetics
PublikacjaA polyurethane (PU)-based powder coating reinforced with vinyltrimethoxysilane (VTMS)-functionalized ZrO2 nanoparticles (V-ZrO2) for thermal stability was developed. Chemical structure, microstructure and thermal degradation kinetics of the prepared coatings were investigated. The peak of aliphatic C–H vibrating bond in the Fourier transform infrared (FTIR) spectrum of V-ZrO2 was a signature of VTMS attachment. Scanning electron...
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Model of optical phantoms thermal response upon irradiation with 975 nm dermatological laser
PublikacjaWe have developed a numerical model describing the optical and thermal behavior of optical tissue phantoms upon laser irradiation. According to our previous studies, the phantoms can be used as substitute of real skin from the optical, as well as thermal point of view. However, the thermal parameters are not entirely similar to those of real tissues thus there is a need to develop mathematical model, describing the thermal and...
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Rigid polyurethane foams modified with ground tire rubber - mechanical, morphological and thermal studies
PublikacjaRigid polyurethane foams, prepared by a single step method, were modified with the two types of ground tire rubber particles, i.e. untreated and thermo-mechanically reclaimed by using a co-rotating twin screw extruder. The foaming process as well as the structure and the physical, mechanical and thermal properties of the resulting foams were investigated. The presence of ground tire rubber decreased the velocity of polymerization....
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Impact of thermal backfill parameters on current-carrying capacity of power cables installed in the ground
PublikacjaProper design of power installations with the participation of power cables buried in homogeneous and thermally well-conductive ground does not constitute a major problem. The situation changes when the ground is non-homogeneous and thermally low-conductive. In such a situation, a thermal backfill near the cables is commonly used. The optimization of thermal backfill parameters to achieve the highest possible current-carrying capacity...
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Structural, mechanical and thermal behavior assessments of PCL/PHB blends reactively compatibilized with organic peroxides
PublikacjaThe efficiency of two commercially available organic peroxides, dicumyl peroxide (DCP) and di-(2-tert-butyl-peroxyisopropyl)-benzene (BIB), during reactive processing of poly (ε-caprolactone)/poly (3-hydroxybutyrate) (PCL/PHB) blends was investigated. The changes in chemical structure of PCL/PHB blends, as a function of organic peroxide type (DCP/BIB) and content (in range: 0–1.0 parts by weight - pbw), were characterized by Fourier...
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Novel Cast Polyurethanes Obtained by Using Reactive Phosphorus-Containing Polyol: Synthesis, Thermal Analysis and Combustion Behaviors
PublikacjaPhosphorus-containing polyol applications in polyurethane synthesis can prevent volatilization of flame retardants and their migration on the surface of a material. In this work, novel cast polyurethanes were prepared by a one-step method with the use of different amounts of phosphorus-containing polyol, 4,4′–diphenylmethane diisocyanate and 1,4-butanediol. The chemical structure, thermal, physicochemical and mechanical properties...
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Influence of artificial thermal ageing on polyester-reinforced and polyvinyl chloride coated AF9032 technical fabric
PublikacjaThe presented work deals with the thermal ageing evaluation for polyester-reinforced and polyvinyl chloride coated fabrics. The architectural fabric AF9032 was exposed to artificial thermal ageing by subjecting the material samples to temperature levels of 80℃ and 90℃ for up to 12 weeks. The mechanical properties of the aged fabric have been separately described by the identified linear piecewise model (with assumption of the elastic...
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A Comparison of Empirical Correlations of Viscosity and Thermal Conductivity of Water-Ethylene Glycol-Al2O3 Nanofluids
PublikacjaBecause of their superb thermal conductivity, nanofluids are seen as new generation of cooling mediums in many engineering applications. It is well established that even a small amount of nanoparticles mixed with a base fluid may result in distinct thermal conductivity enhancement. On the other hand, addition of nanoparticles to the base fluid results in its substantial viscosity increase. Therefore, it is very dicult to evaluate...
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A new viscoelastic method of calculation of low-temperature thermal stresses in asphalt layers of pavements
PublikacjaThe paper presents a new method of calculation of thermal stresses in asphalt layers of pavements induced by cooling or heating. The method, developed by the author, is based on the analytical solution for the linear viscoelastic Burgers model extended numerically for the case of asphalt layers whose rheological parameters are strongly dependent on temperature. The coefficient of thermal expansion and Poisson’s ratio may optionally...
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Microcrystalline Cellulose Management in the Production of Poly(ether-urethane)s- Structure, Morphology, and Thermal Characteristic
PublikacjaIn response to the demand of polymer industry for reducing the use of synthetic chemicals, eco-friendly materials are investigated. In the presented study, bio-based poly(ether-urethane)s were prepared by using microcrystalline cellulose (MCC) and polyether polyol and 1,3-propanediol derived from corn sugar. A step towards sustainability was taken by incorporating bio-based compounds and cellulose, consequently, bio-waste are utilized...
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Phase Change Thermal Energy Storage – The Experience of the Materials Preparation for the Specific Applications.
PublikacjaThermal energy storage and temperature stabilization is very important in many engineering applications. There are three kinds of thermal energy storage: sensible heat storage, latent heat storage and reversible chemical reaction heat storage. Phase change materials (PCM) absorb, store and release large amounts of energy in the form of latent heat, at constant temperature, called the transition temperature. The amount of heat...
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Structure, Mechanical, Thermal and Fire Behavior Assessments of Environmentally Friendly Crude Glycerol-Based Rigid Polyisocyanurate Foams
PublikacjaIn this work, rigid polyisocyanurate foams were prepared at partial substitution (0–70 wt%) of commercially available petrochemical polyol, with previously synthesized biopolyol based on crude glycerol and castor oil. Influence of the biopolyol content on morphology, chemical structure, static and dynamic mechanical properties, thermal insulation properties, thermal stability and flammability was investigated. Incorporation of...
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Synthesis and thermal studies of flexible polyurethane nanocomposite foams obtained using nanoclay modified with flame retardant compound
PublikacjaThis work presents thermal studies of nanocomposites based on the flexible polyurethane (PU) matrix and filled using montmorillonite organically modified with organophosphorus flame retardant compound. Flexible PU nanocomposite foams were prepared in the reaction carried out between reactive alcoholic hydroxyl and isocyanate groups with the ratio of NCO to OH groups equal to 1.05. The amount of an organoclay ranging from 3 to 9...
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How thermal stability of ionic liquids leads to more efficient TiO2-based nanophotocatalysts: Theoretical and experimental studies
PublikacjaIonic liquids (ILs) containing distinct nitrogen-bearing organic cations (pyridinium, pyrrolidinium, imidazolium, ammonium, morpholinium) were first used for the preparation of 23 IL-TiO2 types of composites by ionic liquid assisted solvothermal synthesis. These 23 optimal ILs structures (i.e. compounds exhibiting an optimal combination of specific properties, functionality, and safety) for synthesis and experimental validation...
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Assessment of Thermal Stresses in Asphalt Mixtures at Low Temperatures Using the Tensile Creep Test and the Bending Beam Creep Test
PublikacjaThermal stresses are leading factors that influence low-temperature cracking behavior of asphalt pavements. During winter, when the temperature drops to significantly low values, tensile thermal stresses develop as a result of pavement contraction. Creep test methods can be suitable for the assessment of low-temperature properties of asphalt mixtures. To evaluate the influence of creep test methods on the obtained low-temperature...
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Thermodynamic analysis of the Compressed Air Energy Storage system coupled with the Underground Thermal Energy Storage
PublikacjaImprovement of flexibility is one of the key challenges for the transformation of the Polish Power System aiming at a high share of renewable energy in electricity generation. Flexible and dispatchable power plants will contribute to this ongoing transformation process as they compensate for fluctuations in electricity generation from renewable energy sources such as wind and photovoltaics. In this context, CAES storage tanks are...
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Biopolyols obtained via crude glycerol-based liquefaction of cellulose: their structural, rheological and thermal characterization
PublikacjaIn this work lignocellulose biomass liquefaction was used to produce biopolyols suitable for the manufacturing of rigid polyurethane foams. In order to better evaluate the mechanism of the process, pure cellulose was applied as a raw material. The effect of time and temperature on the effectiveness of liquefaction and the parameters of resulting biopolyols were characterized. The prepared materials were analyzed in terms of their...
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A finite element analysis of thermal energy inclination based on ternary hybrid nanoparticles influenced by induced magnetic field
PublikacjaThe use of hybrid nanoparticles to improve thermal processes is a key method that has implications for a variety of interventions utilized in many sectors. This paper aimed to look into the impacts of ternary nanoparticles on hyperbolic tangent materials to establish their thermal characteristics. Flow describing equations have been explored in the presence of heat production, non-Fourier heat flux, and an induced magnetic field....
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Application of Artificial Neural Networks to Predict Insulation Properties of Lightweight Concrete
PublikacjaPredicting the properties of concrete before its design and application process allows for refining and optimizing its composition. However, the properties of lightweight concrete are much harder to predict than those of normal weight concrete, especially if the forecast concerns the insulating properties of concrete with artificial lightweight aggregate (LWA). It is possible to use porous aggregates and precisely modify the composition...
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Thermal utilization of meat and bone meals. Performance analysis in terms of drying process, pyrolysis and kinetics of volatiles combustion
PublikacjaA development of technology of thermal utilization requires a thorough knowledge of the physicochemical properties, as well as kinetics of combustion of volatiles and char. Due to waste management regulations the meat and bone meal (MBM) is regarded as biofuel constituting one of the alternatives to fossil fuels in the energy market. MBM is a heterogeneous material that may consist of several different fractions. The extensive...
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Pin Angle Thermal Effects on Friction Stir Welding of AA5058 Aluminum Alloy: CFD Simulation and Experimental Validation
PublikacjaThe friction stir welding (FSW) of tool pin geometry plays a critical role in the final properties of the produced joint. The tool pin geometry directly affects the generation of heat and the flow of internal materials during the FSW process. The effects of the FSW tool pin angle on heat generation and internal flow have not been quantitatively investigated in detail. In this manuscript, a validated Computational Fluid Dynamic...
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THE IMPACT OF GROUND TIRE RUBBER TREATMENT ON THE THERMAL CONDUCTIVITY OF FLEXIBLE POLYURETHANE/GROUND TIRE RUBBER COMPOSITES
PublikacjaWaste car tires are burdensome waste, and their utilization is crucial for the natural environment. In many countries, the primary method of their recycling is energy recovery, performed by simple combustion. However, material recycling is much more effective and significantly more beneficial for the natural environment. It results in the generation of ground tire rubber, which can be used to produce polymerrubber composites. It...
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Insights into modification of lignocellulosic fillers with isophorone diisocyanate: structure, thermal stability and volatile organic compounds emission assessment
PublikacjaThis study presents an analysis of the structure and properties of different types of lignocellulosic fillers modified by isophorone diisocyanate (IPDI) to provide insights into the possibility of their application to the manufacturing of wood polymer composites (WPCs). Moreover, it deals with the environmental aspects of modified fillers, by assessment of volatile organic compounds (VOCs) emitted during modification, as well as...
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Thermal degradation assessment of canola and olive oil using ultra-fast gas chromatography coupled with chemometrics
PublikacjaOil blending is often used to enhance the properties of vegetable oils. The admixture of a more thermally stable oil makes the resulting blend more suitable for use in frying. A new method of quality assessment of vegetable oils used in frying is presented in this paper. In this method, ultra-fast gas chromatography coupled with flame ionization detector and chemometrics is employed. Principal component analysis was used for data...
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Glass-ceramic joining of Fe22Cr porous alloy to Crofer22APU: interfacial issues and mechanical properties
PublikacjaThis work deals with the joining of porous Fe22Cr ferritic stainless steel to a dense Crofer22APU plate by using a silica-based, Ba-containing glass-ceramic. The chemical and interfacial stability and the mechanical properties of the joints were evaluated before and after thermal ageing at 700 ◦C for 500hrs. The sintering behaviour of the glass was assessed by using heating stage microscopy (HSM) to study the influence of a porous...
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Structure versus hydrolytic and thermal stability of bio-based thermoplastic polyurethane elastomers composed of hard and soft building blocks with high content of green carbon
PublikacjaNowadays, sustainability plays a key role in the design and synthesis of new materials. One of the methods for the preparation of green materials is incorporation into their structure the monomers with a high content of green carbon. Therefore, the aim of this work was to investigate the influence of the type and molecular mass of two bio-based polyester polyols and bio-glycol on the properties of aliphatic partially bio-based...
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Thermal Instability of Choline Chloride-Based Deep Eutectic Solvents and Its Influence on Their Toxicity─Important Limitations of DESs as Sustainable Materials
PublikacjaDeep eutectic solvents (DESs) have become a hot topic in many branches of science due to their remarkable properties. They have been studied in a wide variety of applications. In particular, choline chloride (ChCl)-based DESs are one of the most commonly used representatives of these fluids. Nevertheless, in order to apply DESs in some fields, it is essential to guarantee their stability, reusability, and biocompatibility. In this...
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Validation of polyurethane-wood composites properties
Dane BadawczeThis study focuses on the development of the PU-WC manufacturing method, the determination of properties of this type of composite, and the indication of its potential application. The mechanical properties of PU-WC were characterized by flexural tests. To determine the thermal properties, dynamic mechanical analysis (DMA) and thermogravimetric analysis...
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Structural properties of mixed conductor Ba1−xGd1−yLax+yCo2O6−δ
PublikacjaBa1−xGd1−yLax+yCo2O6−δ (BGLC) compositions with large compositional ranges of Ba, Gd, and La have been characterised with respect to phase compositions, structure, and thermal and chemical expansion. The results show a system with large compositional flexibility, enabling tuning of functional properties and thermal and chemical expansion. We show anisotropic chemical expansion and detailed refinements of emerging phases as La is...
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Protective properties of Al2O3 + TiO2 coating produced by the electrostatic spray deposition method
PublikacjaMechanical resistance of Al2O3 + TiO2 nanocomposite ceramic coating deposited by electrostatic spray deposition method onto X10CrAlSi18 steel to thermal and slurry tests was investigated. The coating was produced from colloidal suspension of TiO2 nanoparticles dispersed in 3 wt% solution of Al2(NO3)3, as Al2O3 precursor, in ethanol. TiO2 nanoparticles of two sizes, 15 nm and 32 nm, were used in the experiments. After deposition,...
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The Effect of Polyurethane Glycolysate on the Structure and Properties of Natural Rubber/Carbon Black Composites
PublikacjaIn this work the use of polyurethane chemical recycling product (i.e. glycolysis of polyurethane waste realized with the mass excess of polymer) as a plasticizer for natural rubber-based composites was proposed. The effect of plasticizer type (napthenic oil and polyurethane foam glycolysate) and amount (2, 4, 6 or 8 parts per 100 parts of natural rubber) on the processing properties of rubber mixtures and chemical structure, swelling,...
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Study of the effect of thermally reduced graphene oxide on the physical and mechanical properties of flexible polyurethane foams
PublikacjaFlexible polyurethane foams were obtained from a two-component system via the one-step method. The foams were modified with thermally reduced graphene oxide added in the amount equal to 0.25, 0.5 and 0.75 wt%. The morphology, static and dynamic properties, and thermal stability of modified foams were determined. The application of carbon filler resulted in the visible increase in the cell size, apparent density and rigidity of...
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THE INFLUENCE OF PET MECHANICAL PROPERTIES ON SBM PROCESS PARAMETERS – LITERATURE REVIEW
PublikacjaIn the paper it is said about the influence of PET (polyethylene terephthalate) mechanical properties on SBM (stretch blow molding) process output parameters changes. The below paper mentions also about the influence of PET orientation and crystallization processes on mechanical and thermal properties of PET material during SBM process. All mechanical data of PET material and SBM process output parameters changes are from collected...
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Thermal analyses of multiple times processed poly(lactic acid)-carbon black composites
Dane BadawczeThis dataset contains thermal analyses (TGA, DTG, DSC) studies of commercially available ProtoPasta 3D printable filament, composed of poly-lactic acid (PLA) and conductive carbon black (CB) filler. The aim of the study is to observe structural differences and applied properties changes under multiple reprocessing of the composite material at different...
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Processing, Mechanical and Morphological Properties of GTR Modified by SBS Copolymers
PublikacjaIn this work, ground tire rubber (GTR) was thermo-mechanically treated in the presence of styrene-butadiene-styrene (SBS) copolymers. During preliminary investigation, the effects of different SBS copolymer grades, the variable content of SBS copolymer on the Mooney viscosity, and the thermal and mechanical properties of modified GTR were determined. Subsequently, GTR modified by SBS copolymer and cross-linking agents (sulfur-based...
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Green thermoplastic poly(ether-urethane)s – synthesis, chemical structure and selected properties investigation
PublikacjaThis work aimed to characterize the effect of the monomers chemical structure on the selected properties of the green thermoplastic poly(ether-urethane)s. During synthesis two types of polyether biopolyols, 4,4′-diphenylmethane diisocyanate and bio-based 1,3-propanediol were employed. Materials were synthesized with the use of two step method and two different prepolymers, which were mixed together in equimolar quantities. Obtained...
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Properties of LiMnBO3 glasses and nanostructured glass-ceramics
PublikacjaPolycrystalline LiMnBO3 is a promising cathode material for Li-ion batteries. In this work, we investigated the thermal, structural and electrical properties of glassy and nanocrystallized materials having the same chemical composition. The original glass was obtained via a standard melt-quenching method. SEM and 7Li solid-state NMR indicate that it contains a mixture of two distinct glassy phases. The results suggest that the...
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Study of nanomechanical properties of (1-y)BST-yMgO thin films
PublikacjaIn the present study thin films of MgO – modified Ba0.6Sr0.4TiO3 (BST60/40) solid solution were prepared by the sol-gel-type chemical solution deposition method on stainless steel substrates. A multilayer spin-coating approach was utilized for the Ba0.6Sr0.4TiO3-MgO thin film deposition with subsequent thermal annealing at T=650-750C. Dried BST60/40-MgO gel powders were studied with thermogravimetric and differential thermal analysis...
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The influence of PET mechanical properties on Stretch Blow Molding (SBM) process
PublikacjaIn the paper it is said about the influence of PET mechanical properties on SBM process parameters changes. The below paper mentions also about the influence of PET orientation and crystallization processes which have a very big influence on mechanical and thermal properties of PET material during SBM process. All mechanical data of PET material and SBM process parameters change in time are been got from collected literature which...
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Blowing Kinetics, Pressure Resistance, Thermal Stability, and Relaxation of the Amorphous Phase of the PET Container in the SBM Process with Hot and Cold Mold. Part I: Research Methodology and Results
PublikacjaThe technology of filling drinks without preservatives (such as fresh juices, iced tea drinks, vitaminized drinks) is carried out using hot filling. Mainly due to the production costs and lower carbon footprint, polyethylene terephthalate bottles, commonly called PET, are increasingly used in this technology. In this paper, the main aim is to describe the statistical analysis methodology of the influence of the temperature of the...
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Experimental and theoretical study of a vertical tube in shell storage unit with biodegradable PCM for low temperature thermal energy storage applications
PublikacjaThis article presents the experimental investigations of the coconut oil-based TES module for HVAC applications in the ambient and-sub ambient temperature range. To properly study this problem modular experimental module and test loop were developed. Special attention has been paid to study the physical mechanism of the melting/solidification process for natural substance (coconut oil) which has perspectives to be used in thermal...
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Influence of Surface-Modified Montmorillonite Clays on the Properties of Elastomeric Thin Layer Nanocomposites
PublikacjaIn recent years, polyurethane nanocomposites have attracted more attention due to the massive demand for materials with increasingly exceptional mechanical, optical, electrical, and thermal properties. As nanofillers have a high surface area, the interaction between the nanofiller and the polymer matrix is an essential issue for these materials. The main aim of this study is to validate the impact of the montmorillonite nanofiller...
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Blowing Kinetics, Pressure Resistance, Thermal Stability, and Relaxation of the Amorphous Phase of the PET Container in the SBM Process with Hot and Cold Mold. Part II: Statistical Analysis and Interpretation of Tests
PublikacjaThe technology of filling drinks without preservatives (such as fresh juices, iced tea drinks, and vitaminized drinks) is carried out using hot filling. Mainly due to the production costs and lower carbon footprint, polyethylene terephthalate (PET) bottles are increasingly used in this technology. In this paper, the main aim is to describe and interpret the results of statistical analysis of the influence of the temperature of...
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High-conducting Bi4V2-xFexO11-δ ceramics containing Fe2O3 nanocrystals: Structure and properties
PublikacjaThe topography, structure, thermal, magnetic, and electrical properties of Bi4V2-xFexO11-δ ceramics substituted with x = 0.5 and 0.7 Fe were studied. The microscope analysis showed the presence of iron-rich nanocrystals formed on the Bi-Fe-V-O grains. The X-ray diffraction studies confirmed that grains are built mostly of tetragonal Bi4V1.5Fe0.5O10.5 phase. Thermal properties analysis showed an order-disorder type γ ↔ γʹ phase...
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Effect of Coating Material Properties on Tilting-pad Thrust Bearing Performance
PublikacjaPolymer lined tilting-pad bearings demonstrate many advantages over traditional bearing systems. Bearings with a polymer layer in comparison with a babbitted layer show, for example: lower value of friction coefficient (important during start/stops), higher fatigue strength of the coating, better distribution of the load on individual pads due to lower elasticity of the polymers, wider range of operational temperatures or the ability...
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Influence of Bitumen Type and Asphalt Mixture Composition on Low-Temperature Strength Properties According to Various Test Methods
PublikacjaIn regions with low-temperatures, action transverse cracks can appear in asphalt pavements as a result of thermal stresses that exceed the fracture strength of materials used in asphalt layers. To better understand thermal cracking phenomenon, strength properties of different asphalt mixtures were investigated. Four test methods were used to assess the influence of bitumen type and mixture composition on tensile strength properties...
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Microstructure and Electrical Properties of Fe,Cu Substituted (Co,Mn)3O4 Thin Films
PublikacjaIn this work, thin films (~1000 nm) of a pure MnCo2O4 spinel together with its partially substituted derivatives (MnCo1.6Cu0.2Fe0.2O4, MnCo1.6Cu0.4O4, MnCo1.6Fe0.4O4) were prepared by spray pyrolysis and were evaluated for electrical conductivity. Doping by Cu increases the electrical conductivity, whereas doping by Fe decreases the conductivity. For Cu containing samples, rapid grain growth occurs and these samples develop cracks...
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Rigid polyurethane foams with different flame retardants and their physical and mechanical properties
PublikacjaRigid polyurethane foams (PUFs) containing 3, 6 or 9 % of one of of two selected fire retardants (FR): oligomeric ethyl ethylene phosphate (Fyrol PNX) and expandable graphite (EG) were prepared, inspected and compared to foam without that fillers as the control. The thermal stability of PUFs was described by horizontal test according to norm: UL 94 HB. Compressive strength and physical properties (density, fragility and water absorption)...
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Bio‑derived polyurethanes obtained by non‑isocyanate route using polyol‑based bis(cyclic carbonate)s—studies on thermal decomposition behavior
PublikacjaNon-isocyanate polyurethanes (NIPUs) constitute one of the most prospective groups of eco-friendly materials based on their phosgene-free synthesis pathway. Moreover, one of the steps of their obtaining includes the use of carbon dioxide (CO 2 ), which allows for the promotion of the development of carbon dioxide capture and storage technologies. In this work, non- isocyanate polyurethanes were obtained via three-step synthesis...
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Imaging of morphological and physicochemical changes occuring in the structure of austenitic steel due to the thermal sensitization
Dane BadawczeIn polycrystalline materials, grain boundaries are always where phenomena such as surface diffusion, sedimentation and corrosion occur. They have a significant impact on the macroscopic properties of the construction material [1]. In addition to inhomogeneities such as manganese sulphide inclusions formed during the metallurgical process, interfacial...
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Influence of external walls' thermal capacitance on indoor thermal comfort
PublikacjaThe doctoral thesis presents the results of numerical investigations on the influence of walls’ thermal capacitance on indoor thermal comfort. A proper set of thermal parameters of a building structure can considerably limit the heating / cooling demand, and passively increase the indoor thermal comfort. However the effect of building thermal capacitance on indoor conditions is complex and not always beneficial. Among a great number...
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Effects of the polyhistidine tag on kinetics and other properties of trehalose synthase from Deionococcus geothermalis
PublikacjaTwo recombinant trehalose synthases from Deinococcus geothermalis (DSMZ 11300) were compared. A significant influence of the artificial polyhistidine tag was observed in protein constitution. The recombinant trehalose synthase from D. geothermalis with His6 -tag has a higher K m value of 254 mM, in comparison with the wild-type trehalose synthase (K m 170 mM), and displayed a lower activity of maltose conversion when compared...
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Do Phenyl Substituents Affect the Properties of Azobenzocrown Derivatives?
PublikacjaNew products of photo- and thermal rearrangements of 19-membered azoxybenzocrown with phenyl substituents in benzene rings in the para positions to oligooxyethylene fragments are characterized. The yields of photochemical transformations depend on the solvent. Para-hydroxyazocrown is formed with yields over 50% in propan-2-ol. Ortho-hydroxyazobenzocrown is obtained with yields up to 70% in toluene/acetic acid mixture. Macrocyclic...
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Shape Memory Polyurethane Materials Containing Ferromagnetic Iron Oxide and Graphene Nanoplatelets
PublikacjaIntelligent materials, such as memory shape polymers, have attracted considerable attention due to wide range of possible applications. Currently, intensive research is underway, in matters of obtaining memory shape materials that can be actuated via inductive methods, for example with help of magnetic field. In this work, an attempt was made to develop a new polymer composite—polyurethane modified with graphene nanoplates and...