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Spinning Fluids Reactor: A new design of a gas – liquid contactor
PublikacjaCurrent trends in chemical reactor design are based on adapting these to the requirements of a particular chemical process. Processes involving reactions between the gas and liquid phase in particular require precise adjustment of all parameters. The common denominator for most modern design solutions is enhancement of the mass transfer area and the overall volumetric mass transfer coefficient. Gas – liquid contactors evolved from...
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Zastosowanie addytywów w separacji pianowej białek serwatkowych i białek mlecznych
PublikacjaZaproponowano proces separacji pianowej do wydzielania białek ze strumieni poprodukcyjnych przemysłu mleczarskiego Ponadto zaproponowano zastosowanie w separacji pianowej białek serwatkowych i mlecznych addytywów dopuszczonych ustawą do stosowania w żywności. Jako cel pracy przyjęto uzyskanie wyników uzasadniających wybór takich addytywów, które intensyfikują przebieg i polepszają wynik procesu separacji pianowej białek. W części...
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Improvement of Oxygen Electrode Performance of Intermediate Temperature Solid Oxide Cells by Spray Pyrolysis Deposited Active Layers
PublikacjaIntermediate temperature solid oxide fuel cells oxygen electrodes are modified by active interfacial layers. Spray pyrolysis is used to produce thin (≈500 nm) layers of mixed ionic and electronic conductors: Sm0.5Sr0.5CoO3−δ (SSC), La0.6Sr0.4CoO3−δ (LSC), La0.6Sr0.4Co0.2Fe0.8O3−δ (LSCF), and Pr6O11 (PrOx) on the electrode–electrolyte interface. The influence of the annealing temperature on the electrode polarization (area specific...
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Poly(ε-Caprolactone)/Brewers’ Spent Grain Composites—The Impact of Filler Treatment on the Mechanical Performance
PublikacjaWaste lignocellulose materials, such as brewers’ spent grain, can be considered very promising sources of fillers for the manufacturing of natural fiber composites. Nevertheless, due to the chemical structure differences between polymer matrices and brewers’ spent grain, filler treatment should be included. The presented work aimed to investigate the impact of fillers’ reactive extrusion on the chemical structure and the poly(ε-caprolactone)/brewers’...
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Coffee Silverskin as a Multifunctional Waste Filler for High-Density Polyethylene Green Composites
PublikacjaThis work aims to describe the coffee silverskin effect as a lignocellulosic waste filler for high-density polyethylene (HDPE) composites development. The main task was to determine various modification effects resulting from the complex chemical composition of coffee silverskin containing compounds with potential antioxidative properties, including caffeine, polyphenols, tannins, or melanoidins. The processing, thermal, physicochemical,...
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Interface analysis of compatibilized polymer blends
PublikacjaThis chapter seeks to address the interface location in the compatibilized polymer blends and paves the way for quantitative analysis of interface in terms of interfacial tension and interfacial adhesion to provide support for understanding the relationship between morphology and ultimate properties in the compatibilized polymer blends through the lens of interface. Since understanding and analysis of interfacial phenomena in the...
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Glass-ceramic sealants and steel interconnects: accelerated interfacial stability and reactivity tests at high temperature
PublikacjaHigh-temperature reactions between glass-ceramic sealants and Fe-Cr alloy interconnects may lead to the formation of undesirable phases, and consequently degradation of solid oxide fuel/electrolyser devices. In this work, three different glass-ceramic sealants (Na-containing, Ba-containing, Sr-containing compositions) and Fe22Cr stainless steel powders (raw and pre-oxidised) are considered in order to test their chemical reactivity...
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On the Bending of Multilayered Plates Considering Surface Viscoelasticity
PublikacjaWe discuss the bending resistance of multilayered plates taking into account surface/interfacial viscoelasticity. Within the linear surface viscoelasticity we introduce the surface/interfacial stresses linearly dependent on the history of surface strains. In order to underline the surface viscoelasticity contribution to the bending response we restrict ourselves to the elastic behaviour in the bulk. Using the correspondence principle...
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Surface and interfacial anti-plane waves in micropolar solids with surface energy
PublikacjaIn this work, the propagation behaviour of a surface wave in a micropolar elastic half-space with surface strain and kinetic energies localized at the surface and the propagation behaviour of an interfacial anti-plane wave between two micropolar elastic half-spaces with interfacial strain and kinetic energies localized at the interface have been studied. The Gurtin–Murdoch model has been adopted for surface and interfacial elasticity....
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Molecular dynamics study on the role of solvation water in the adsorption of hyperactive AFP to the ice surface
PublikacjaUsing computer simulations, the early stages of the adsorption of the CfAFP molecule to the ice surface were analyzed. We found that the ice and the protein interact at least as early as when the protein is about 1 nm away from the ice surface. These interactions are mediated by interfacial solvation water and are possible thanks to the structural ordering of the solvent. This ordering leads to positional preference of the protein...
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Bending of a Three-Layered Plate with Surface Stresses
PublikacjaWe discuss here the bending deformations of a three-layered plate taking into account surface and interfacial stresses. The first-order shear deformation plate theory and the Gurtin-Murdoch model of surface stresses will be considered and the formulae for stiffness parameters of the plate are derived. Their dependence on surface elastic moduli will be analyzed.
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The role of bile salts in digestion
PublikacjaBile salts (BS) are bio-surfactants present in the gastrointestinal tract (GIT) that play a crucial role in the digestion and absorption of nutrients. The importance of BS for controlled release and transport of lipid soluble nutrients and drugs has recently stimulated scientific interest in these physiological compounds. BS are so-called facial amphiphiles showing a molecular structure that is very distinct from classical surfactants....
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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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Assessment of microstructure, physical and thermal properties of bitumen modified with LDPE/GTR/elastomer ternary blends
PublikacjaLDPE/GTR/elastomer ternary blends with variable LDPE/GTR ratio and constant elastomer content were prepared via melt-compounding. Obtained LDPE/GTR/elastomer blends were applied as thermoplastic modifiers into bitumen. Microstructure, physical and thermal properties of the modified bitumen were determined. It was observed that chemical composition of LDPE/GTR/elastomer blends has significant influence on their density and rheological...
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AFM imaging of surface of modern soldering alloy
Dane BadawczeFollowing the announcement in 2006 of European Union directives aimed at limiting the use of lead in electronic products, there was an urgent need to use lead-free solders in the electronics industry. Due to production requirements, it is necessary to use solders with different melting points. To replace the low-melting eutectic Sn 37 wt. Pb, the most...
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Recycling of Waste Rubber by Thermo-Mechanical Treatment in a Twin-Screw Extruder
PublikacjaRecycling of waste tires is a significant issue considering both environmental and economic aspects. One of the leading recycling routes is the shredding of tires resulting in the generation of ground tire rubber. This material can be easily introduced into various polymer matrices as a filler, reducing the use of conventionally applied petroleum-based materials. In such cases, it is essential to ensure sufficient interfacial compatibility,...
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Perfect thermal contact of hyperbolic conduction semispaces with an interfacial heat source
PublikacjaThe problem of thermal contact between two bodies with a heat source at their interface presents great scientific and practical interest. On the time scale of a nanosecond or shorter, heat propagation should be considered in the form of thermal waves of finite speeds. This study investigated the thermal behaviour of hyperbolic conduction semispaces in perfect thermal contact subjected to the action of an interfacial heat source....
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The influence of polypropylene-block/graft-polycaprolactone copolymers on melt rheology, morphology, and dielectric properties of polypropylene/polycarbonate blends
PublikacjaThe paper discusses the relationship between rheology and morphology of immiscible polypropylene (matrix))/polycarbonate (dispersed phase) blends compatibilized with novel polypropylene-polycaprolactone block and graft copolymers. Transmission electron microscopy (TEM) experiments revealed uniform droplet morphologies and a reduction of the average size of the dispersed phase upon addition of the compatibilizer. The results suggested...
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Interfacial water controls the process of adsorption of hyperactive antifreeze proteins onto the ice surface
PublikacjaA mechanism of interactions between the ice-binding surface of a hyperactive antifreeze protein molecule and the ice surface is proposed, involving the influence of water present between the two surfaces on the behavior of the approaching molecule. It is demonstrated that the interfacial water, even before its full solidification, can act as a factor that pushes away or pulls nearer the protein molecule to ensure its proper positioning....
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Structural and physico-mechanical properties of natural rubber/GTR composites devulcanized by microwaves: Influence of GTR source and irradiation time
PublikacjaGround tire rubber from car and truck was modified using microwave irradiation at variable time. The irradiated ground tire rubber was used as filler in composites based on natural rubber. The composites, with high content of ground tire rubber, were prepared using an internal batch mixer and subsequently cross-linked at 160℃. The influence of the ground tire rubber source (car/truck) and irradiation time on structure, physico-mechanical...
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Cross-linking of sodium caseinate-structured emulsion with transglutaminase alters postprandial metabolic and appetite responses in healthy young individuals
PublikacjaThe physico-chemical and interfacial properties of fat emulsions influence lipid digestion and may affect postprandial responses. The aim of the present study was to determine the effects of the modification of the interfacial layer of a fat emulsion by cross-linking on postprandial metabolic and appetite responses. A total of fifteen healthy individuals (26·5 (sem 6·9) years and BMI 21·9 (sem 2·0) kg/m2) participated in a cross-over...
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GTR/Thermoplastics Blends: How Do Interfacial Interactions Govern Processing and Physico-Mechanical Properties?
PublikacjaIn this work, GTR/thermoplastics blends (in ratio 50/50 and 75/25 wt.%) were prepared by melt-compounding in an internal mixer. During research, trans-polyoctenamer rubber (TOR), ethylene-vinyl acetate copolymer (EVA), ethylene-octene copolymer (EOC), and linear low-density polyethylene (LLDPE), were used in their thermoplastic phase. Microstructure and processing-performance property interrelationships of the studied materials...
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Emulsifi ers from renewable materials: an eco-friendly synthesis and properties
PublikacjaThe focus of this study was the preparation of novel bio based polyglycerol emulsifiers characterized by a one pot synthesis, thus by modified properties with respect to interfacial activity and effectiveness as emulsion stabilizers. The final products of the esterification process, carried out in the presence of carboxylates were used directly as emulsifiers (without purification or fractionation). Polyglycerol emulsifiers obtained...
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Wave transmission across surface interfaces in lattice structures
PublikacjaWithin the lattice dynamics formulation, we present an exact solution for anti-plane surface waves in a square lattice strip with a surface row of material particles of two types separated by a linear interface. The considered problem is a discrete analog of an elastic half-space with surface stresses modelled through the simplified Gurtin–Murdoch model, where we have an interfacial line separating areas with different surface...
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Fabrication of exfoliated graphite reinforced silicone rubber composites - Mechanical, tribological and dielectric properties
PublikacjaThe effect of exfoliated graphite (EG) on the mechanical, tribological and dielectric properties of the silicone rubber (QM) composites has been systematically investigated and analysed. Morphological analysis of the composites helps to understand the interfacial interaction between the filler and the rubber matrix as well as wear mechanism respectively. An enhancement in the mechanical, tribological and dielectric properties was...
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Fabrication of exfoliated graphite reinforced silicone rubber composites - Mechanical, tribological and dielectric properties
PublikacjaThe effect of exfoliated graphite (EG) on the mechanical, tribological and dielectric properties of the silicone rubber (QM) composites has been systematically investigated and analysed. Morphological analysis of the composites helps to understand the interfacial interaction between the filler and the rubber matrix as well as wear mechanism respectively. An enhancement in the mechanical, tribological and dielectric properties was...
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Surface finite viscoelasticity and surface anti-plane waves
PublikacjaWe introduce the surface viscoelasticity under finite deformations. The theory is straightforward generalization of the Gurtin–Murdoch model to materials with fading memory. Surface viscoelasticity may reflect some surface related creep/stress relaxation phenomena observed at small scales. Discussed model could also describe thin inelastic coatings or thin interfacial layers. The constitutive equations for surface stresses are...
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Interrelated shape memory and Payne effect in polyurethane/graphene oxide nanocomposites
PublikacjaWe report the fabrication of graphene oxide (GO) based polyurethane (PU) nanocomposites by a simple method of mixing and their shape memory properties at different temperatures. Both the polymer and the filler were synthesized in the laboratory by simple and easy methods – PU by pre-polymer method and GO by improved graphene oxide synthesis method. High molecular level dispersion of GO platelets within the PU matrix and thus good...
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SIMULATIONS OF FRACTURE IN CONCRETE BEAMS UNDER BENDING USING A CONTINUUM AND DISCRETE APPROACH
PublikacjaThe paper describes two-dimensional meso-scale results of fracture in notched concrete beams under bending. Concrete was modelled as a random heterogeneous 4-phase material composed of aggregate particles, cement matrix, interfacial transitional zones and air voids. Within continuum mechanics, the simulations were carried out with the finite element method based on a isotropic damage constitutive model enhanced by a characteristic...
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The impact of thermomechanical and chemical treatment of waste Brewers’ spent grain and soil biodegradation of sustainable Mater-Bi-Based biocomposites
PublikacjaDue to the massive plastic pollution, development of sustainable and biodegradable polymer materials is crucial to reduce environmental burdens and support climate neutrality. Application of lignocellulosic wastes as fillers for polymer composites was broadly reported, but analysis of biodegradation behavior of resulting biocomposites was rarely examined. Herein, sustainable Mater-Bi-based biocomposites filled with thermomechanically-...
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MODELLING OF CONCRETE FRACTURE AT AGGREGATE LEVEL USING DEM BASED ON X-RAY mu CT IMAGES OF INTERNAL STRUCTURE
PublikacjaThe paper describes two-dimensional meso-scale numerical results of fracture in notched concrete beams under quasi-static three-point bending. Concrete was modelled as a random heterogeneous 4-phase material composed of aggregate particles, cement matrix, interfacial transitional zones (ITZs) and air voids. As a numerical approach, the discrete element method (DEM) was used. The concrete micro-structure in calculations was directly...
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Mesoscopic simulations of crack propagation in concrete using cohesive elements
PublikacjaThe paper presents results of two-and three-dimensional meso-scale simulations of fracture in notched concrete beams subjected to three-point bending test. Concrete was assumed as a 3-phase material composed of aggregate grains placed in the cement matrix with Interfacial Transitional Zones (ITZs) between then. In 2D simulations macro-voids were also taken into account. The particle distribution was taken from real concrete beams...
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Coatings in arthroplasty [online]
PublikacjaThe modern coatings used in arthroplasty for long term implants are reviewed. The phosphate coatingsare the most popular technique to improve the bone-implant interfacial strength and promote theosseointegration. The plasma spraying, electrophoretic precipitation, powder metallurgy, ion beamsputtering, high velocity oxy-fuel (HVOF) combustion spraying, sol-gel technique, biomimeticdeposition are mostly used to obtain the phosphate,...
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Proteolysis of whey protein isolates in nanoemulsion systems: impact of nanoemulsification and additional synthetic emulsifiers
PublikacjaNanoemulsions are currently of interest in the functional food sector because their small droplet size (100–500 nm) provides a number of potential advantages over conventional emulsions. This study concerned the behavior of nanoemulsions stabilized with whey proteins and two synthetic emulsifiers (Tween 80 and Croduret), and exposed to conditions simulating the human upper gastrointestinal tract. In particular, the effect of synthetic...
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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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A negative effect of carbon phase on specific capacity of electrode material consisted of nanosized bismuth vanadate embedded in carbonaceous matrix
PublikacjaLithium-ion batteries (LIBs) are widely used all over the world. The LIBs belong to a renewable energy source and energy storage devices. The increase in energy demand causes that new materials of higher energy and higher power densities are still under investigation. Herein, we compare electrochemical properties of bismuth vanadate (BiVO4) embedded and not embedded into carbonaceous matrix as an anode material along with structural...
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Two-dimensional simulations of concrete fracture at aggregate level with cohesive elements based on X-ray lCT images
PublikacjaThe paper presents results of two-dimensional meso-scale simulations of fracture in notched concrete beams subjected to three-point bending test. Concrete was assumed as a 4-phase material composed of aggregate grains placed in the cement matrix, interfacial transitional zones (ITZs) and macro-voids. The particle distribution was taken from real concrete beams on the basis of X-ray lCT images. Comprehensive numerical analyses were carried...
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Wettability of shale rock as an indicator of fracturing fluid composition
PublikacjaShales have become one of the main unconventional gas resources in the world. However, physicochemical properties of rocks are still at the center of research. There have been conducted major researches in wettability of shales by fluids and advances in understanding and control of shale rock wettability. Also influence of interfacial phenomena on a production capacity of reservoirs have been made. The aim of this study is to find...
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Impact damage in SiO2 nanoparticle enhanced epoxy – Carbon fibre composites
PublikacjaLow velocity impact behaviour of nano-SiO2 enhanced carbon fibre/epoxy composites for naval applications is reported. Epoxy resin matrix was enhanced by 1- 8 wt% SiO2 nanoparticles, based on industrial surface-modified nanosilica. Impact parameters: force, deformation, energy, damage size were recorded. The most pronounced effect was damage size decrease; e.g. ∼28% recorded by infrared thermography and X-ray computed radiography...
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Jeffreys heat conduction in coupled semispaces subjected to interfacial heating
PublikacjaA Jeffreys heat conduction problem for coupled semispaces subjected to the action of an interfacial heat source was defined. An analytical solution of the problem was derived for a polynomial specific power of the heat source using the Laplace transform approach. The asymptotic and parametric analysis was performed for different ratios of thermal conductivities , thermal diffusivities , thermal relaxation times and coefficients...
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DETERMINATION OF THE HYDROXYL NUMBER OF GROUND TIRE RUBBER PARTICLES VIA MODIFIED TEST METHOD FOR ISOCYANATE GROUPS
PublikacjaNowadays, considering the environmental trends and law regulations associated with the circular economy, it is very important to seek for the methods of by-products and waste utilization. The example of such material, which requires the attention and recycling method is ground tire rubber generated during recycling of post-consumer car tires. It can be introduced into various polymer matrices as a filler, but to enhance its effectivity...
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Numerical investigations of discrete crack propagation in Montevideo splitting test using cohesive elements and real concrete micro-structure
PublikacjaThe paper is aimed at accurately predicting the discrete fracture process in concrete specimens under complex stress states in two dimensional (2D) simulations. Plain concrete specimens subjected to Montevideo splitting test (MVD) were used for consideration due to non-negligible shear stresses impact in this type of test. In order to reflect the heterogeneous nature of the concrete, the meso-structure of the samples was included...
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Reclaimed Rubber/Poly(ε‐caprolactone) Blends: Structure, Mechanical, and Thermal Properties
PublikacjaThe amount of elastomeric waste, especially from tires is constantly increasing on a global scale. The recycling of these residua should be considered a priority. Compounding the waste rubbers with other polymers can be an excellent alternative to reuse waste materials. This procedure requires solving the issue of the lack of compatibility between the waste rubber particles and other polymers. Simultaneously, there is a claim for...
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Insights into Compatibilization of Poly(ε-caprolactone)-based Biocomposites with Diisocyanates as Modifiers of Cellulose Fillers
PublikacjaThis study aimed to analyze the impact of cellulose fillers’ modification with diisocyanates on the performance of composites based on the poly(ε-caprolactone) (PCL) matrix. Four most commonly used diisocyantes (isophorone, hexamethylene, toluene, and methylene diphenyl) were applied as modifiers of cellulose fillers (5 and 15 wt% per mass of filler). Modified fillers were introduced in the amount of 30 wt% into the PCL matrix....
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Morphology and mechanical properties of polyamide/clay nanocomposites toughened with NBR/NBR-g-GMA: A comparative study
PublikacjaThis work highlights the importance of nanoclay dispersion state in the nanocomposites containing polyamide 6 (PA6), nanoclay and elastomers as well as clay localization at the interface of thermoplastic/elastomer. Morphology and mechanical properties of a series of nanocomposites containing acrylonitrile butadiene rubber (NBR), glycidyl methacrylate-grafted NBR (NBR-g-GMA), and combined NBR/NBR-g-GMA were compared and discussed...
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Effect of ectoine on hydration spheres of peptides–spectroscopic studies
PublikacjaIn this paper, we use FTIR spectroscopy to characterize the hydration water of ectoine, its interactions with two peptides–diglycine and NAGMA, and the properties of water molecules in the hydration spheres of both peptides changed by the presence of the osmolyte. We found that the interaction of ectoine with the peptide hydration shells had no effect on its own hydration sphere. However, the enhanced hydration layer of the osmolyte...
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Size effect in concrete under splitting tension
PublikacjaThe size effect is a fundamental phenomenon in concrete materials. It denotes that both the nominal structural strength and material ductility always decrease with increasing element size under tension. In the paper splitting tensile tests on cylindrical concrete specimens with the different diameter were carried out. Two types of the loading strip (plywood board and steel cylinder) were used. The concrete strength and ductility...
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In-Situ Processing of Biocomposites via Reactive Extrusion
PublikacjaLaw regulations, economic and environmental factors are the main causes for the rapidly growing interests in biocomposites’ research, conducted currently in a number of academic and industrial scientific centers. However, weak polymer matrix/filler interactions, common in biocomposites, result in unsatisfactory mechanical properties, which limit their practical applications. From many attempts performed to solve this problem, in-situ...
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Fabrication of wormhole-like YSZ and Ni-YSZ by the novel soft-hard template CTAB/NaCl-assisted route. Suppressing Ni coalescence in SOFC
PublikacjaA novel one-pot synthesis route leading to the formation of a wormhole-like structure was developed for the successful fabrication of porous YSZ and Ni-YSZ systems. This method involved co-precipitation in the presence of the micelle-forming agents CTAB/Pluronic P123 and crystallising NaCl. The obtained skeletons were mechanically stable and presented almost 50% uniform, open porosity without using any additional pore-formers....
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High-density Polyethylene - Expanded Perlite Composites: Structural Oriented Analysis of Mechanical and Thermomechanical Properties
PublikacjaAs part of this work, research was carried out on the effect of the addition of expanded perlite (PR) on the mechanical and thermomechanical properties of high-density polyethylene (PE) composites. Composites containing from 1 to 10 wt% of the inorganic filler were produced. Polyethylene-based composites manufactured by twin-screw extrusion and formed in the compression molding process were subjected to mechanical, thermomechanical,...