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Wyniki wyszukiwania dla: mechanical-properties
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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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Preparation, characterization and antimicrobial activity of polyvinyl alcohol/gum arabic/chitosan composite films incorporated with black pepper essential oil and ginger essential oil
PublikacjaIn this study, biocomposite films based on polyvinyl alcohol (PVA), gum arabic (GA) and chitosan (CS) incorporated with BPEO and GEO were fabricated by solvent casting method. FTIR, XRD, SEM and DSC were performed with mechanical and antimicrobial properties of PVA/GA/CS films with and without BPEO and GEO. The BPEO and GEO incorporated PVA/GA/CS films were significantly inhibited the growth of Bacillus cereus, Staphylococcus aureus,...
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Analysis of the cyclic load-unload-reload tests of VALMEX aged fabric
PublikacjaThe paper presents mechanical response of the VALMEX fabric during the cyclic loading-unloading and re-loading experiments. Two types of the aged material used for nearly 20 years as the roofing of the Forest Opera in Sopot (Poland) have been tested. The results have been separately obtained for the warp and fill di-rections. The comparative analysis has revealed that the material aged in service is more durable in the fill di-rection,...
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Raman Scattering versus Strain Engineering in Phosphorene Nanostructures: An Ab Initio Studies
PublikacjaThe one-dimensional nanoribbons made from phosphorene are novel structures with great applicability potential in material science. The significant carrier mobility combined with intrinsic semiconductor properties makes them ideal for application in electronics, and they are excellent candidates for sensing material. The lack of a well–established multiscale modelling strategy for phosphorene nano optoelectronic devices is one of...
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Underwater Local Cavity Welding of S460N Steel
PublikacjaIn this paper, a comparison of the mechanical properties of high-strength low-alloy S460Nsteel welded joints is presented. The welded joints were made by the gas metal arc welding (GMAW)process in the air environment and water, by the local cavity welding method. Welded joints were testedfollowing the EN ISO 15614-1:2017 standard. After welding, the non-destructive—visual, penetrant,radiographic, and ultrasonic (phased array) tests...
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AFM visualization of Mg alloy surface modification
Dane BadawczeMagnesium alloys with additives improving their mechanical properties are valued as materials with low density and elasticity coefficient. Additionally, their biocompatibility and biodegradability make them interesting in prosthetic applications. However, the last of these features, valuable in medicine, contradicts the industrial needs for the described...
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Tensile test of 1.4307 / X2CrNi18-9 / AISI 304L grade austenitic steel
Dane BadawczeShip structures and their components are build mainly of steel. Hull steel is used to build the hull structure. Some structural elements, such as RSW (Refrigerated See Water) tanks, or LNG (Liquid Natural Gas) tanks - gas transported at temperatures below -162° C, are build from austenitic steels. Austenitic steels have a different microstructure and...
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Tensile test of 1.4541 / X6CrNi18-10 / AISI 321 grade austenitic steel
Dane BadawczeShip structures and their components are build mainly of steel. Hull steel is used to build the hull structure. Some structural elements, such as RSW (Refrigerated See Water) tanks, or LNG (Liquid Natural Gas) tanks - gas transported at temperatures below -162° C, are build from austenitic steels. Austenitic steels have a different microstructure and...
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Concept and Implementation of Innovative Scalable Wind Turbine Emulator with Doubly Fed Asynchronous Machine
PublikacjaThis paper presents the design of an innovative scalable wind turbine emulator. The system’s hardware and software components are described in detail including test results, demonstrating the research potential of the proposed design. The uniqueness of the proposed solution lies in its scalability, achieved despite the use of physical devices with fixed parameters. This scalability allows for the flexible shaping of the system’s...
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Full-field in vivo experimental study of the strains of a breathing human abdominal wall with intra-abdominal pressure variation
PublikacjaThe presented study aims to assess the mechanical behaviour of the anterior abdominal wall based on an in vivo experiment on humans. Full-field measurement of abdominal wall displacement during changes of intra-abdominal pressure is performed using a digital image correlation (DIC) system. Continuous measurement in time enables the observation of changes in the strain field during breathing. The understanding of the mechanical...
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A green route for high-performance bio-based polyurethanes synthesized from modified bio-based isocyanates
PublikacjaThe need for sustainability and a circular economy leads to the development of innovative greener materials and technologies. This paper is focused on a novel class of bio-based polyurethanes (PUs) synthesized with the use of bio-monomers including bio-based isocyanates. The novelty of this work is related to the usage of bio-based modified isocyanate via a two-step solvent-free synthesis of novel cast bio-based poly(ester-urethanes)...
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Applying molecular dynamics simulation to take the fracture fingerprint of polycrystalline SiC nanosheets
PublikacjaGraphene-like nanosheets are the key elements of advanced materials and systems. The mechanical behavior of the structurally perfect 2D nanostructures is well documented, but that of polycrystalline ones is less understood. Herein, we applied molecular dynamics simulation (MDS) to take the fracture fingerprint of polycrystalline SiC nanosheets (PSiCNS), where monocrystalline SiC nanosheets (MSiCNS) was the reference nanosheet....
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Segmented bio-based polyurethane composites containing powdered cellulose obtained from novel bio-based diisocyanate mixtures
PublikacjaA considerable number of research works focus on the positive influence of cellulose on the properties of polymer-based composites and their wide range of application possibilities. The present work is focused on the synthesis of novel bio-based polyurethane (bio-PU) composites filled with powdered cellulose (microcellulose, MC) in an amount of 5 wt.%. Bio-PU composites were synthesized via a non-solvent prepolymer method. First,...
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Poloxamer: A versatile tri-block copolymer for biomedical applications
PublikacjaPoloxamers, also called Pluronic, belong to a unique class of synthetic tri-block copolymers containing central hydrophobic chains of poly(propylene oxide) sandwiched between two hydrophilic chains of poly(ethylene oxide). Some chemical characteristics of poloxamers such as temperature-dependent self-assembly and thermo-reversible behavior along with biocompatibility and physiochemical properties make poloxamer-based biomaterials...
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Experimental Studies of Concrete-Filled Composite Tubes under Axial Short- and Long-Term Loads
PublikacjaThe paper presents experimental studies on axially compressed columns made of concrete-filled glass fiber reinforced polymer (GFRP) tubes. The infill concrete was C30/37 according to Eurocode 2. The investigated composite pipes were characterized by different angles of fiber winding in relation to the longitudinal axis of the element: 20, 55 and 85 degrees. Columns of two lengths, 0.4 m and 2.0 m, were studied. The internal diameter...
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Biomechanical properties of 3D-printed bone models
PublikacjaBone lesions resulting from large traumas or cancer resections can be successfully treated by directly using synthetic materials or in combination with tissue engineering methods (hybrid). Synthetic or hybrid materials combined with bone tissue’s natural ability for regeneration and biological adaptation to the directions of loading, allow for full recovery of its biological functions. Increasing interest in new production methods...
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How the Dimensions of Plant Filler Particles Affect the Oxidation-Resistant Characteristics of Polyethylene-Based Composite Materials
PublikacjaThis study analyzed the possibility of using plant-originated waste materials (black and green tea dust) as functional polyethylene fillers. The dependence between the size of the filler particles and their antioxidant potential is discussed. Six fractions were selected: below 50 µm, 50–100 µm, 100–200 µm, 200–400 µm, 400–630 µm and 630–800 µm. Significant differences between the effect of particle size and the antioxidant properties...
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Investigating lubricants behaviour in microgravity for vibration damping purposes
PublikacjaVibration is one of the harshest environments an object is exposed to during and after launch into space on a launch vehicle. Such vibrations should be damped to avoid destruction of the spacecraft or its elements. Currently, active and material damping is used. A possibility of using lubrication as the damping factor is suggested by some research. MoS2 is a typical solid lubricant used in space applications. Its properties vary...
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Shape memory thin films of Polyurethane: Does graphene content affect the recovery behavior of Polyurethane nanocomposites?
PublikacjaThin nanocomposite films of polyurethane have received remarkable attention due to their shape memory properties. As most of the reports focus on the beneficial aspects of the presence of nanofillers such as graphene nanoplatelets (GNPs) introduced into shape memory polymers, some research results reveal the opposite trend. The polyether/polyester-based polyurethane was synthesized through a condensation polymerization and the...
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Types of Surface Impurities versus the Quality of Brazed Joints
PublikacjaBrazing is one of the primary joining processes increasingly often applied in industry. Because of their mechanical properties, overlap joints are particularly popular when making brazed structures. The use of brazed joints in structures of critical importance requires that particular attention be paid to joint quality, e.g. by the appropriate cleaning of surfaces to be joined. The article presents results of non-destructive tests...
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Induction Assisted Hybrid Friction Stir Welding of Dissimilar Materials AA5052 Aluminium Alloy and X12Cr13 Stainless Steel
PublikacjaThis research aimed to study the induction in-situ heated hybrid friction stir welding (IAFSW) method to join AA5052 aluminium alloy with X12Cr13 stainless steel (SS) to enhance joint strength. The potency of this method on the mechanical properties and microstructural characterizations were also investigated. The results show that the transverse tensile strength gained was 94% of the AA5052 base metal that is 229.5 MPa. This superior...
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Cellulose Nanomaterials in Biomedical, Food, and Nutraceutical Applications: A Review
PublikacjaNanotechnology with bionanomaterials have tremendous potential to enhance and utilize for nutrient and bioactive absorption, drug delivery systems, pharmaceutical, and nutraceutical field through various applications. Cellulose nanomaterials are green materials that are obtained from renewable sources and possess exceptional mechanical strength and biocompatibility. The associated unique physical and chemical properties have made...
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Experimental and numerical evaluation of mechanical behaviour of composite structural insulated wall panels under edgewise compression
PublikacjaA composite structural insulated sandwich panel (CSIP) is a quite novel approach to the idea of sandwich structures. A series of natural-scale experimental test is required each time a change in panel’s geometry is planned and a reliable computational tool is required to precede actual laboratory testing with virtual simulations. An attempt of creating such a tool has been made with use of a commercial FEM code ABAQUS, in order...
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New Design of Axial Piston Pump with Displaced Swash Plate Axis of Rotation for Hydro-Mechanical Transmissions
PublikacjaThis paper presents a prototype design of an axial piston pump with displaced swash plate axis of rotation in two directions of discharge with electronic control intended for installation on a hydraulic-mechanical gearbox dedicated to working machines. The effect of displacement of the swash plate rotation axis on dead space volume and volumetric efficiency is presented. The construction and principle of operation of the capacity...
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Self-organising maps in the analysis of strains of human abdominal wall to identify areas of similar mechanical behaviour.
PublikacjaThe study refers to the application of a type of artificial neural network called the Self-Organising Map (SOM) for the identification of areas of the human abdominal wall that behave in a similar mechanical way. The research is based on data acquired during in vivo tests using the digital image correlation technique (DIC). The mechanical behaviour of the human abdominal wall is analysed during changing intra-abdominal pressure....
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Mechanical response of 6061-T6 aluminium alloy subjected to dynamic testing at low temperature: Experiment and modelling
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Assessment with mechanical Barkhausen effect of residual stress in grain oriented polycrystalline 3% Si-Fe sheet
PublikacjaW tym artykule zostały opisane badania naprężeń resztkowych w blachach wykonanych z 3% si-fe o zorientowanym ziarnie za pomocą mechanicznego efektu barkhausena (mebn). badano blachy o 3 różnych orientacjach ziaren względem głównej osi próbki: 0, 45, 90 stopni. badania mebn przeprowadzano wzbudzając drgania skrętne oraz drgania gięte. zmierzone maksima obwiedni napięcia skutecznego mebn znajdują się dla badanych próbek w regionie...
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Polygons vs. clumps of discs: A numerical study of the influence of grain shape on the mechanical behaviour of granular materials
PublikacjaWe performed a series of numerical vertical compression tests on assemblies 01 20 granular material using a Discrete Element code and studied the results with regard to the grain shape. The samples consist of 5000 grains made from either 3 overlapping discs (clumps - grains with concavities) or six-edged polygons (convex grains). These two grain type have similar external envelope, which is a fund ion of a geometrical parameter...
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Effectiveness of a mathematical model in simulating nonlinear mechanical behaviour of a seismic isolation system made of polymeric bearings
PublikacjaThe present study was focused on determining the effectives of a nonlinear mathematical model in simulating complex mechanical behaviour of a seismic isolation system made of Polymeric Bearings. The proposed mathematical model defines the lateral force as a nonlinear function of the shear displacement and the deformation velocity. The effectiveness of the proposed mathematical model was verified by comparing the seismic response...
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Assessment with mechanical Barkhausen effect of residual stress in grain oriented polycrystalline 3% Si-Fe sheet
PublikacjaZbadano za pomocą mechanicznego efektu Barkhausena poziom napręzeń wewnętrznych w plikrystalicznej płycie z 3% Si-Fe o zorientowanym ziarnie.
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ENERGY ANALYSIS OF THE PROPULSION SHAFT FATIGUE PROCESS IN A ROTATING MECHANICAL SYSTEM PART III DIMENSIONAL ANALYSIS
PublikacjaThis article presents the third and last part of the problem of diagnosing the fatigue of marine propulsion shafts in terms of energy with the use of the action function, undertaken by the authors. Even the most perfect physical models of real objects, observed under laboratory conditions and developed based on the results of their research, cannot be useful in diagnostics without properly transferring the obtained results to the...
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Optical and structural properties of polycrystalline CVD diamond films grown on fused silica optical fibres pre-treated by high-power sonication seeding
PublikacjaIn this paper, the growth of polycrystalline chemical vapour deposition (CVD) diamond thin films on fused silica optical fibres has been investigated. The research results show that the effective substrate seeding process can lower defect nucleation, and it simultaneously increases surface encapsulation. However, the growth process on glass requires high seeding density. The effects of suspension type and ultrasonic power were...
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Entire fracture surface topography parameters for fatigue life assessment of 10H2M steel
PublikacjaIn this paper, the entire fracture surface approach was used to assess an effect of 280,000 h of exploitation under internal pressure of 2.9 MPa and high temperature of 540 °C on the fatigue response of 10H2M (10CrMo9–10) power engineering steel. The mechanical testing was carried out on the hourglass specimens produced from the as-received, unused pipeline and the same material after long-time exploitation. The uniaxial tensile...
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Hydrogen Embrittlement and Oxide Layer E ect in the Cathodically Charged Zircaloy-2
PublikacjaThe present paper is aimed at determining the less investigated effects of hydrogen uptake on the microstructure and the mechanical behavior of the oxidized Zircaloy-2 alloy. The specimens were oxidized and charged with hydrogen. The different oxidation temperatures and cathodic current densities were applied. The scanning electron microscopy, X-ray electron diffraction spectroscopy, hydrogen absorption assessment, tensile, and...
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Novel method of estimation of inertial and dissipative parameters of a railway pantograph model
PublikacjaAn increase in electric railway vehicles service velocity requires that correct interaction between the pantograph and the catenary is ensured. This implies the need for developing mathematical models of pantographs and catenaries and determining their parameters. The article presents a method to determine parameters of mechanical joints of a railway pantograph based on analysis of pantograph subassemblies in swinging motion. The...
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Właściwości złączy różnoimiennych stopu niklu Incoloy 800H ze stalą odporną na korozję 316L
PublikacjaW artykule przedstawiono problemy związane z wykonywaniem połączeń różnoimiennych typu Incoloy 800HT – austenityczna stal odporna na korozję 316L. Wykonano badania nieniszczące oraz niszczące, których wyniki pozwoliły na weryfikacje jakości wykonanych złączy próbnych. Nie stwierdzono występowania niezgodności spawalniczych oraz uzyskano wysokie właściwości wytrzymałościowe złączy. Badania metalograficzne ujawniły poprawne struktury...
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Koncepcja i analiza sensora/aktuatora piezoelektrycznego do pomiaru procesu starzenia się ludzkiej skóry
PublikacjaNiniejszy artykuł przedstawia nową koncepcję piezoelektrycznego sensora/aktuatora przeznaczonego do pomiaru właściwości mechanicznych tkanek miękkich a w szczególności skóry ludzkiej. Wyjaśnione jest analityczne podejście z wykorzystaniem schematu zastępczego Mason’a określającego aktuator w stanie rezonansu oraz opis metody impedancji elektromechanicznej wykorzystanej w systemie pomiarowym. Analiza z użyciem metody elementów...
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Petrophysical analyses of rock construction materials from the Roman rural settlement in Podšilo bay on Rab island (NE Adriatic, Croatia)
PublikacjaThis article presents the results of petrophysical analyses of limestones and sandstones used for the construction of the wall structures of a Roman rural settlement located in Podšilo Bay on Rab Island (Croatia). An on-site analysis of the walls indicated the use of different lithotypes, which is an uncommon case in the area. So far, no petrophysical properties of the applied materials have been tested, and their provenance...
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Tensile test of 1.4571 / X6CrNiMoTi17-12-2 / AISI 316Ti grade austenitic steel
Dane BadawczeShip structures and their components are build mainly of steel. Hull steel is used to build the hull structure. Some structural elements, such as RSW (Refrigerated See Water) tanks, or LNG (Liquid Natural Gas) tanks - gas transported at temperatures below -162° C, are build from austenitic steels. Austenitic steels have a different microstructure and...
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Thermomagnetic behavior of a semiconductor material heated by pulsed excitation based on the fourth-order MGT photothermal model
PublikacjaThis article proposes a photothermal model to reveal the thermo-magneto-mechanical properties of semiconductor materials, including coupled diffusion equations for thermal conductivity, elasticity, and excess carrier density. The proposed model is developed to account for the optical heating that occurs through the semiconductor medium. The Moore–Gibson–Thompson (MGT) equation of the fourth-order serves as the theoretical framework...
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Surface effects of network materials based on strain gradient homogenized media
PublikacjaThe asymptotic homogenization of periodic network materials modeled as beam networks is pursued in this contribution, accounting for surface effects arising from the presence of a thin coating on the surface of the structural beam elements of the network. Cauchy and second gradient effective continua are considered and enhanced by the consideration of surface effects. The asymptotic homogenization technique is here extended to...
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Wpływ azotowania jarzeniowego i laserowego nadtapiania na odporność kawitacyjną stali X5CrNi18-10
PublikacjaNierdzewne stale austenityczne charakteryzują się doskonałą odpornością korozyjną, aczkolwiek niskimi właściwościami mechanicznymi. W wielu przypadkach ogranicza to ich eksploatację w warunkach przemysłowych. Ponadto, nierdzewne stale austenityczne są wrażliwe na korozję lokalną w obecności jonów halogenkowych. Technologie materiałowe, które dają potencjalne możliwości otrzymywania korzystnego wpływu na właściwości mechaniczne...
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Preparation and characterization of natural rubber composites highly filled with brewers' spent grain/ground tire rubber hybrid reinforcement
PublikacjaBrewers' spent grain (BSG) and ground tire rubber (GTR) were applied as low-cost hybrid reinforcement natural rubber (NR). The impact of BSG/GTR ratio (in range: 100/0, 75/25, 50/50, 25/75 and 0/100 phr) on processing and performance properties of highly filled natural rubber composites was evaluated by oscillating disc rheometer, Fourier-transform infrared spectroscopy, thermogravimetric analysis, scanning electron microscopy,...
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Green engineered biomaterials for bone repair and regeneration: Printing technologies and fracture analysis
PublikacjaDespite the exceptional self-regeneration properties of bone, severe injuries often require additional surgical intervention such as using artificial bone constructs. These structures need to meet a number of criteria regarding their structure, performance, alongside the rate and the mechanism of erosion and fracture when implanted, for stimulating the regeneration of defected bone and, more critically providing support in the...
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Poly-L-Lysine-functionalized fluorescent diamond particles: pH triggered fluorescence enhancement via surface charge modulation
PublikacjaRecently, the interest in applying fluorescent diamond particles (FDPs) containing nitrogen-vacancy (NV) centers for enhancing the mechanical and chemical properties of some materials, biological imaging, and sensing has been expanding rapidly. The unique properties of NV centers such as intensive, time-stable fluorescence, and an electron spin, which exhibits long coherence time and may be manipulated using external stimuli, such...
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Tailoring Diffusional Fields in Zwitterion/Dopamine Copolymer Electropolymerized at Carbon Nanowalls for Sensitive Recognition of Neurotransmitters
PublikacjaThe importance of neurotransmitter sensing in the diagnosis and treatment of many psychological illnesses and neurodegenerative diseases is non-negotiable. For electrochemical sensors to become widespread and accurate, a long journey must be undertaken for each device, from understanding the materials at the molecular level to real applications in biological fluids. We report a modification of diamondized boron-doped carbon nanowalls...
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Flame-Retardant Polymer Materials Developed by Reactive Extrusion: Present Status and Future Perspectives
PublikacjaThe development of flame retardant polymer materials has two roots, one in materials design, and the other in materials processing. Over recent decades, different types and classes of flame retardant polymer materials have been commercialized to meet safety requirements in the construction, automotive, and coatings industries. In the vast majority of cases, the design and fabrication of new materials presenting low fire hazards...
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Medical-Grade PCL Based Polyurethane System for FDM 3D Printing—Characterization and Fabrication
PublikacjaThe widespread use of three-dimensional (3D) printing technologies in medicine has contributed to the increased demand for 3D printing materials. In addition, new printing materials that are appearing in the industry do not provide a detailed material characterization. In this paper, we present the synthesis and characterization of polycaprolactone (PCL) based medical-grade thermoplastic polyurethanes, which are suitable for forming...
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Harmonic Vibrations of Nanosized Magnetoelectric Bodies with Coupled Surface and Interphase Effects: Mathematical Models and Finite Element Approaches
PublikacjaThe harmonic problems for piezomagnetoelectric nanosized bodies with taking into account the coupled damping and surface effects are considered on the base of the generalized Gurtin-Murdoch model. In the development of previous investigations, the coupled mechanical, electric and magnetic surface effects with surface inertial terms are introduced into the model. For a homogeneous model, the composite material is considered as homogeneous...
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Synergistic Effects of Bitumen Plasticization and Microwave Treatment on Short-Term Devulcanization of Ground Tire Rubber
PublikacjaGround tire rubber (GTR) was mechano-chemically modified with road bitumen 160/220 and subsequently treated using a microwave radiation. The combined impact of bitumen 160/220 content and microwave treatment on short-term devulcanization of GTR was studied by thermal camera, wavelength dispersive X-ray fluorescence spectrometry (WD-XRF), static headspace, and gas chromatography-mass spectrometry (SHS-GC-MS), thermogravimetric analysis...