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Evaluation of adhesive forces and the specific surface energy of zirconia stabilized by yttria with alumina additions ceramic by AFM method
PublicationThe adhesive forces and the specific surface energy of ceramic material surfaces are very important for further tribological and biomedical applications of ceramics. Partially stabilized zirconia (zirconium oxide) is popular for manufacturing various medical products. ZrO2 stabilized by Y2O3 with additions of 5 wt% alumina was produced by slip casting method with a subsequent sintering. Structure and chemical composition of ceramic...
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KTaO3 a perovskite for water and air treatment
PublicationPerovskites are inorganic compounds that exhibit dielectric properties. These minerals belong to the crystal ceramics family. These compounds are described by the formula: ABX3 where, A and B are 2, 3 or 4 valuable metal ions, and X is an ion of oxygen or fluorine. An example of perovskite is the compound KTaO3. There are many methods for producing KTaO3, but the hydrothermal method is most commonly used. Perovskites can be characterized...
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Characterization and Technical Application of Fine Photocatalytical Particles - A Study of the Immobilization of Photocatalysts
PublicationThe main aim of this dissertation was the transfer of photocatalytical laboratory scale experiments to semi-technical scale. Preliminary experiments of the purification of organic chlorine-loaded waters and the immobilization of photocatalysts were performed, which yielded the research back to the roots of synthesis. The first applied research was carried out on treatment of recreational water. Several light sources, particularly...
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Synthesis of new antrapyridazone derivatives - a novel group of anticancer agents active on a multidrugresistant(MDR) tumor cell lines
PublicationNovel antrapyridazone derivatives were synthesized and biologically evaluated in order tobroaden the data on structure-activity relationship of this class of cytostatics. Recent literaturedata prove that acetamides react better with aryl chlorides. A new approach based onintroduction of other amides form into aromatic ring in Ullmann was tested. This new methodcould give better yields and make purification step more convenient.
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New approach to noncausal identification of nonstationary stochastic systems subject to both smooth and abrupt parameter changes
PublicationIn this paper we consider the problem of finiteintervalparameter smoothing for a class of nonstationary linearstochastic systems subject to both smooth and abrupt parameterchanges. The proposed parallel estimation scheme combines theestimates yielded by several exponentially weighted basis functionalgorithms. The resulting smoother automatically adjustsits smoothing bandwidth to the type and rate of nonstationarityof the identified...
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Bilateral Multi-Issue Negotiation Between Active Documents and Execution Devices
PublicationMobile document-agents are often in conflict with execution devices when attempting to perform activities of the business process they implement, since preferences of device owners may change depending on their current location and the actual class of the device in use. The paper proposes a bilateral negotiation mechanism based on a simple bargaining game that can effectively resolve such conflicts without any third party support.
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Integrated production technology of cylindrical surfaces by turning and burnishing
PublicationThe method is based on a combination of previously used two separate operations namely machining and burnishing in a one complex operation implemented on a lathe.In the case of machining shafts and hydraulic cylinders of steel C45 is possible to obtain a surface roughness Ra=0,16 - 0,32 micrometers, dimensional accuracy class 7-8 according to ISO standards, and increase in the hardness of the surface up to 40%.
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Homoclinics for singular strong force Lagrangian systems
PublicationWe study the existence of homoclinic solutions for a class of generalized Lagrangian systems in the plane, with a C1-smooth potential with a single well of infinite depth at a point ξ and a unique strict global maximum 0 at the origin.Under a strong force condition around the singular point ξ, via minimization of an action integral, we will prove the existence of at least two geometrically distinct homoclinic solutions.
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Experimental and numerical evaluation of mechanical behaviour of composite structural insulated panels
PublicationComposite structural insulated panels (CSIPs) are novel prefabricated elements for structural applications. Panels under consideration are made from glass-fibre reinforced magnesia cement boards as facesheets and expanded polystyrene foam (EPS) as a core. Quasi-static full-scale and model bending tests under monotonic loading were performed to recognize mechanical properties of CSIPs in flexure. In addition, tensile, compressive,...
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Experimental examination of an elastomeric polymer
PublicationA new method of repairing damaged structures by filling the cracks with a specially prepared elastomeric polymer mass has been recently proposed. This new and innovative technique, known as the Flexible Joint Method (FJM), is mainly dedicated to masonries and historical objects, where minimum intervention is permitted. The flexible joint bonds the disrupted elements and ensures further safe exploitation of a damaged structure....
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Luminescent properties of Ln3+ doped tellurite glasses containing AlF3
PublicationThe low-phonon energy tellurite glasses TeO2-BaO-Bi2O3 and TeO2-BaO-Bi2O3-AlF3 triply doped with Eu3+, Tb3+, Tm3+ ions in two different molar ratios were synthesized using melt-quenching technique. Their structure and luminescence properties were widely investigated by X-ray Diffraction (XRD), Differential Scanning Calorimetry (DSC), Fourier Transform Infrared Spectroscopy (FTIR) and Photoluminescence Spectroscopy (PL). The luminescence...
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Polymer electrolytes with ionic liquids
PublicationSolid polymer electrolytes are solutions of salts in the macromolecular polymeric compound. Excellent process ability, flexibility, non-flammability and non-reactivity make them ideal materials for electrochemical devices. The problem in their use is limited conductivity. It increases with increasing salt concentration in the polymer, but at the same time the condition is to increase the glass transition temperature of the polymer...
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Microfluidic devices for photo-and spectroelectrochemical applications
PublicationThe review presents recent developments in electrochemical devices for photo- and spectroelectrochemical investigations, with the emphasis on miniaturization (i.e., nanointerdigitated complementary metal-oxide-semiconductor devices, micro- and nano-porous silicon membranes or microoptoelectromechanical systems), silica glass/microreactors (i.e., plasmonic, Raman spectroscopy or optical microcavities) or polymer-based devices (i.e.,...
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Badania porównawcze wpływu grubości ścianki powłoki o przekroju niekołowym, wykonanej z tworzywa GRP, w obiekcie gruntowo-powłokowym
PublicationW artykule przedstawiono badania porównawcze przepustów wykonanych z tworzywa GRP (Glass Reinforcement Poliester) zabudowanych w warunkach naturalnych i obciążanych układem sił symulujących obciążenia komunikacyjne zgodne z „Modelem Obciążenia 1” wg [7]. Analizowano dwie konstrukcje o identycznym przekroju poprzecznym (profil dzwonowy DN3000/2400), ale różnej grubości ścianki: standardowej 45 mm i zredukowanej 35 mm. Badania obejmowały...
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Chromogenic azomacrocycles with imidazole residue: Structure vs. properties
PublicationNew diazo macrocycles linked by hydrocarbon chain bearing imidazole or 4-methylimidazole residue have been synthetized with satisfactory yield (24–55%). The structure of macrocycles was confirmed by X-ray analysis and spectroscopic methods (1H NMR, MS, FTIR). Metal cation complexation studies were carried out in acetonitrile and acetonitrile-water system. It was found that azomacrocyles form triple-decker complexes with lead(II)....
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Highly sensitive microwave sensors based on open complementary square split-ring resonator for sensing liquid materials
PublicationThis paper presents high-sensitivity sensors based on open complementary square split-ring resonator and modified open complementary split-ring resonator operating at 4.5 GHz and 3.4 GHz, respectively. The sensors are designed for the detection of multiple liquid materials, including distilled water, methanol, and ethanol. The liquid under test is filled in a glass container loaded using a pipette. Compared to the conventional...
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Stabilization of the pyrochlore phase of Mn2Sb2O7 by double substitution
PublicationPolycrystalline samples of (Ce4+Mn2+3)(Ga3+Sb5+3)O14 were synthesized by a high-temperature solid-state reaction. In contrast with the parent Mn2Sb2O7 compound that adopts a rhombohedral or monoclinic structure at T > 600 °C, the pyrochlore structure of CeMn3GaSb3O14 is retained up to at least T = 1070°C. High-resolution synchrotron x-ray diffraction measurements show no sign of a superstructure or distortion from cubic symmetry...
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Influence of plasmon resonance on the luminescence of titanium dioxide thin films doped with rare earth ions
PublicationIn this work the study of the optical properties of europium doped titanium dioxide thin films (TiO2:Eu) enhanced by gold plasmonic nanostructures are presented. Plasmonic platforms were manufactured by thermal annealing of thin film of Au, deposited on a Corning glass substrate. As a result of thermal treatment, gold spherical nanostructures with average dimensions of 50 nm were obtained. Luminescent TiO2:Eu film was deposited...
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Comparative Study of the Reinforcement Type Effect on the Thermomechanical Properties and Burning of Epoxy-Based Composites
PublicationAramid (AF), glass (GF), carbon (CF), basalt (BF), and flax (FF) fibers in the form of fabrics were used to produce the composites by hand-lay up method. The use of fabrics of similar grammage for composites’ manufacturing allowed for a comprehensive comparison of the properties of the final products. The most important task was to prepare a complex setup of mechanical and thermomechanical properties, supplemented by fire behavior...
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Influence of Water-Induced Degradation of Polytetrafluoroethylene (PTFE)-Coated Woven Fabrics Mechanical Properties
PublicationThe impact of water-induced degradation on the mechanical properties of the chosen two PTFE-coated, glass threads woven fabrics is investigated in this paper. The paper begins with a survey of literature concerning the investigation and determination of coated woven fabric properties. The authors carried out the uniaxial tensile tests with an application of flat and curved grips to establish the proper values of the ultimate tensile...
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COMPUTER-AIDED CONSTRUCTION AT DESIGNING REINFORCED CONCRETE COLUMNS AS PER EC
PublicationThe article presents the author’s computer program for designing and dimensioning columns in reinforced concrete structures taking into account phenomena affecting their behaviour and information referring to design as per EC. The computer program was developed with the use of C++ programming language. The program guides the user through particular dimensioning stages: from introducing basic data such as dimensions, concrete...
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Divide and not forget: Ensemble of selectively trained experts in Continual Learning
PublicationClass-incremental learning is becoming more popular as it helps models widen their applicability while not forgetting what they already know. A trend in this area is to use a mixture-of-expert technique, where different models work together to solve the task. However, the experts are usually trained all at once using whole task data, which makes them all prone to forgetting and increasing computational burden. To address this limitation,...
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Tight bounds on the complexity of semi-equitable coloring of cubic and subcubic graphs
PublicationWe consider the complexity of semi-equitable k-coloring, k>3, of the vertices of a cubic or subcubic graph G. In particular, we show that, given a n-vertex subcubic graph G, it is NP-complete to obtain a semi-equitable k-coloring of G whose non-equitable color class is of size s if s>n/3, and it is polynomially solvable if s, n/3.
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Regularity of weak solutions for aclass of elliptic PDEs in Orlicz-Sobolev spaces
PublicationWe consider the elliptic partial differential equation in the divergence form $$-\div(\nabla G(\nabla u(x))) t + F_u (x, u(x)) = 0,$$ where $G$ is a convex, anisotropic function satisfying certain growth and ellipticity conditions We prove that weak solutions in $W^{1,G}$ are in fact of class $W^{2,2}_{loc}\cap W^{1,\infty}_{loc}$.
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KOMPUTER W LABORATORIUM VS LABORATORIUM W KOMPUTERZE
PublicationAbstract. In March 2020, all of the sudden, university teachers have been made to run all the classes remotely. But, how to deal with lab classes for future engineers? Different aspects of teaching labs on Moodle, that should be taken in consideration, are not only connected with the content of the class, but also with transferring the knowledge and materials to the students in a way that would avoid distractions and help students...
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Bell-Type Inequalities from the Perspective of Non-Newtonian Calculus
PublicationA class of quantum probabilities is reformulated in terms of non-Newtonian calculus and projective arithmetic. The model generalizes spin-1/2 singlet state probabilities discussed in Czachor (Acta Physica Polonica:139 70–83, 2021) to arbitrary spins s. For s → ∞ the formalism reduces to ordinary arithmetic and calculus. Accordingly, the limit “non-Newtonian to Newtonian” becomes analogous to the classical limit of a quantum theory
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Prediction of Processor Utilization for Real-Time Multimedia Stream Processing Tasks
PublicationUtilization of MPUs in a computing cluster node for multimedia stream processing is considered. Non-linear increase of processor utilization is described and a related class of algorithms for multimedia real-time processing tasks is defined. For such conditions, experiments measuring the processor utilization and output data loss were proposed and their results presented. A new formula for prediction of utilization was proposed...
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Towards a classification of networks with asymmetric inputs
PublicationCoupled cell systems associated with a coupled cell network are determined by (smooth) vector fields that are consistent with the network structure. Here, we follow the formalisms of Stewart et al (2003 SIAM J. Appl. Dyn. Syst. 2, 609–646), Golubitsky et al (2005 SIAM J. Appl. Dyn. Syst. 4, 78–100) and Field (2004 Dyn. Syst. 19, 217–243). It is known that two non-isomorphic n-cell coupled networks can determine the same sets of...
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The complexity of zero-visibility cops and robber
PublicationWe consider the zero-visibility cops & robber game restricted to trees. We produce a characterisation of trees of copnumber k and We consider the computational complexity of the zero-visibility Cops and Robber game. We present a heavily modified version of an already-existing algorithm that computes the zero-visibility copnumber of a tree in linear time and we show that the corresponding decision problem is NP-complete on a nontrivial...
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DBpedia and YAGO as Knowledge Base for Natural Language Based Question Answering—The Evaluation
PublicationThe idea of automatic question answering system has a very long history. Despite constant improvement of the systems asking questions in the natural language requires very complex solutions. In this paper the DBpedia and YAGO are evaluated as a knowledge bases for simple class 1 and 2 question answering system. For this purpose a question answering system was designed and implemented. The proposed solution and the knowledge bases...
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Biobatteries and biofuel cells with biphenylated carbon nanotubes
PublicationSingle-walled carbon nanotubes covalently biphenylated are used for the construction of cathodes in a flow biobattery and in flow biofuel cell. Zinc covered with a hopeite layer is the anode in the biobattery and glassy carbon electrode covered with bioconjugates of single-walled carbon nanotubes with glucose oxidase and catalase is anode of the biofuel cell. The potentials of the electrodes are measured vs. the Ag/AgCl reference...
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Some Progress on Total Bondage in Graphs
PublicationThe total bondage number b_t(G) of a graph G with no isolated vertex is the cardinality of a smallest set of edges E'⊆E(G) for which (1) G−E' has no isolated vertex, and (2) γ_t(G−E')>γ_t(G). We improve some results on the total bondage number of a graph and give a constructive characterization of a certain class of trees achieving the upper bound on the total bondage number.
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An Influence of Factors of Flow Condition, Particle and Material Properties on Slurry Erosion Resistance
PublicationThe degradation of materials due to slurry erosion is the serious problem which occurs in the power industries. The paper presents actual knowledge about an influence of individual factors connected with flow conditions, particles and material properties on the slurry erosion resistance. Among the factors connected with operating conditions, an influence of impact angle, and velocity of impact, particle concertation and liquid...
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QUASI-DISTRIBUTED NETWORK OF LOW-COHERENCE FIBER-OPTIC FABRY-PÉROT SENSORS WITH CAVITY LENGTH-BASED ADDRESSING
PublicationDistributed measurement often relies on sensor networks. In this paper, we present the construction of low coherent fiber-optic Fabry-Pérot sensors connected into a quasi-distributed network. We discuss the mechanism of spectrum modulation in this type of sensor and the constraints of assembly of such sensors in the network. Particular attention was paid to separate the signals from individual sensors, which can be achieved by...
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Structure and transport properties of donor-doped barium strontium cobaltites
PublicationIn this work, Nb-substituted barium strontium cobaltites Ba0.5Sr0.5Co1-xNbxO3-δ (x = 0 – 0.4) have been fabricated and studied. The structural analysis showed that the Nb content influences the lattice constant as well as the distance between the (Co, Nb) and oxygen atoms. The study of morphology of samples showed that the Nb content does not change the porosity, grain size and morphology of the ceramics. The total electrical conductivity...
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Smart Materials in Architecture: Useful Tools with Practical Applications or Fascinating Inventions for Experimental Design?
PublicationFor at least several decades smart or so-called intelligent materials, being the result of great advancements in material engineering, appear in architecture in different applications. Most of them are called "smart" because of their inherent properties: a real-time response to environmental stimuli. There are also those considered to be "smart" due to smart design: their original structure or the composition of their materials...
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General paradigm for distilling classical key from quantum states
PublicationIn this paper, we develop a formalism for distilling aclassical key from a quantum state in a systematic way, expandingon our previous work on a secure key from bound entanglement(Horodecki et al., 2005). More detailed proofs, discussion, andexamples are provided of the main results. Namely, we demonstratethat all quantum cryptographic protocols can be recast in away which looks like entanglement theory, with the only changebeing...
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A graphical approach to yield and boundary surfaces of selected hypoplastic constitutive equations
PublicationThe article describes how to identify the boundary and yield surface for hypoplastic constitutive equations proposed by Wu, Gudehus and Bauer. It is shown how to identify and plot the surfaces for any equation in this class. Calculation errors are analyzed characteristic for appleid set of numerical formulas. In the paper there are computer links to the source code prepared in the MATLAB system, based on istructions in the article....
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Generalized Gradient Equivariant Multivalued Maps, Approximation and Degree
PublicationConsider the Euclidean space Rn with the orthogonal action of a compact Lie group G. We prove that a locally Lipschitz G-invariant mapping f from Rn to R can be uniformly approximated by G-invariant smooth mappings g in such a way that the gradient of g is a graph approximation of Clarke’s generalized gradient of f . This result enables a proper development of equivariant gradient degree theory for a class of set-valued gradient...
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The use of thin diamond films in fiber optic low-coherence interferometers”
PublicationIn this paper we present the use of thin diamond films in fiber-optic low-coherence interferometers. Two kinds of diamond surfaces were used: undoped diamond film and boron-doped diamond film. They were deposited on glass plates as well as silicon layers. A conventionally used mirror was used as a reference layer. Diamond films were deposited using Microwave Plasma Enhanced Chemical Vapour Deposition (μPE CVD) system. Measurements...
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Transparent thin films of Cu-TiO2 with visible light photocatalytic acitivity
PublicationThin films of Cu–TiO2 with a high level of transparency were prepared by a dip-coating procedure on the glass surface. CuCl2 was used as a copper precursor added during sol – gel synthesis of TiO2. The extension of optical absorption into the visible region of as-prepared thin films was indicated by UV/Vis spectroscopy. Only the anatase phase was detected by X-ray di ffraction analysis (XRD). The presence of copper in the structure...
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The influence of temperature on properties of the polymer flexible joint used for strengthening historical masonries
PublicationA new method of repairing damaged structures by filling the cracks with a specially prepared elastomeric polymer mass has been recently proposed. This new and innovative technique, known as the Flexible Joint Method (FJM), is mainly dedicated to masonries and historical objects, where minimum intervention is permitted. The flexible joint bonds the disrupted elements and ensures further safe exploitation of a damaged structure....
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Chemical treatment of crystalline silicon solar cells as a main stage of pv modules recycling = Obróbka chemiczna krzemowych ogniw słonecznych jako najważniejszy etap w recyklingu modułów fotowoltaicznych
PublicationIn recent years, photovoltaic systems have gained worldwide recognition and popularity as a environmentally friendly way of solving energetic problems. However, a problem of utilizing worn out photovoltaic systems, amount of which will rapidly increase in the future, is yet to be solved. Establishing a technology of recycling and reusing obsolete photovoltaic panels is a necessity.Photovoltaic modules in crystalline silicon solar...
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Morphology and the physical and thermal properties of thermoplastic polyurethane reinforced with thermally reduced graphene oxide
PublicationIn this study, thermally reduced graphene oxide (TRG)-containing polyurethane nanocomposites were obtained by the extrusion method. The content of TRG incorporated into polyurethane elastomer systems equaled 0.5, 1.0, 2.0 and 3.0 wt%. The morphology, static and dynamic mechanical properties, and thermal stability of the modified materials were investigated. The application of TRG resulted in a visible increase in material stiffness...
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Influence of cyclic frozen and defrost on mechanical properties of polytetrafluoroethylene (PTFE)-coated woven fabrics
PublicationThis research aims to determine the influence of the cyclic process of freezing and defrosting on the mechanical properties of the chosen glass fibres and PTFE-coated woven fabrics. The specimens were subjected to freezing at about −20 °C for 4 h and thawing by full immersion into the water at about +20 °C for 4 h. The fabric samples after 25 and 50 frozen cycles were air-dried at room temperature for one week and then subjected...
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Impact of the glazed roof on acoustics of historic interiors
PublicationThe paper discusses the adverse acoustic phenomena occurring in the semi-open interiors (courtyards, yards) covered with a glass roof. Particularly negative is the rever-beration noise, which leads to the degradation of the utility functions of the resulting spaces. It involves the drastically reducing the intelligibility of speech, loss of natural sounding of music, problems with the sound system, as well as disturbances in the...
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Composites in energy storing prosthetic feet
PublicationComposites reinforced with carbon and glass fibers have become the commonly used material in the production of energy storing prosthetic feet (ESPF/elastic feet prostheses). Their properties ensure a stable and light structure that allows for accumulation, storage and release of energy during walking, thus ensuring an increase in gait efficiency. Depending on the modification of the composite in terms of fiber selection, their...
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Recycled Polyurethane as a Second Phase in Thermoset Blends and Its Effect on Thermal Degradation Kinetics Studies
PublicationA new approach is introduced in the modification of thermosetting polymer by using different amount of polyurethane of waste origin. The post consumer polyurethane foam coatings are degraded using glycolysis process and the recycled product is further converted into new polyurethane. The blending of recycled polyurethane with epoxy exhibits transparency and produces nanostructures. The effective interaction between two polymers...
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Impact resistance of plain and twill fabric in GFRP measured by active thermography
PublicationThis paper discusses the impact resistance of glass-fibre reinforced polymer (GFRP) composites depending on the type of reinforcement – plain or twill weave. The values of impact energy were: 3J, 10J and 15J. Specimens featuring twill weave transferred higher force during the impact as compared with plain weave specimens. It was observed that an increase of impact energy was accompanied by an increase of the disproportion in...
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Properties of Barium Cerate Thin Films Formed Using E-Beam Deposition
PublicationThis article focuses on the properties of the BaCeO3 thin films formed by electron-beam vapor deposition and investigates the formation of barium cerates on supports with different thermal expansion coefficients (Stainless Steel, Invar, Glass Sealing, and Inconel substrates) and the influence of the technological parameters on the properties of the formed thin films with an emphasis on the stability of the films. Morphology and...