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Hazardous material-related propagation of the effects of train accidents in the subgrade
PublicationA large part of the transport of hazardous materials is carried out by rail. Therefore, the security of these transports is becoming increasingly important. Every catastrophe involving dangerous materials has a negative impact on the participants of the incident and the surrounding environment, because its range is generally not local. It follows that in the event of a catastrophe, its effects should be minimized and remediation...
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Usefulness of Keystroke Dynamics Features in User Authentication and Emotion Recognition
PublicationThe study presented in the article focuses on keystroke dynamics analysis applied to recognize emotional states and to authenticate users. An overview of some studies and applications in these areas is presented. Then, an experiment is described, i.e. the way of collecting data, extracting features, training classifiers and finding out the most appropriate feature subsets. The results show that it is difficult to indicate a universal...
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The occurrence of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in the chosen area of Svalbard
PublicationIn the recent years, scientists have been paying more attention to the impact of compounds of anthropogenic origin on the environment. Polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) are both groups of stable organic compounds, difficult to biodegrade, and potentially toxic. Because of their affinity to lipids, they can accumulate in fat tissue and exert influence on animal health. This paper present...
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Criteria for evaluation and selection of the best offer for the Contract Engineer service
PublicationThe purpose of the legal regulations regarding public procurement in EU countries is to ensure effective funds' spending. When assessing and selecting the best offer, the contracting entities have at their disposal many different criteria, including non-price criteria. Their proper selection and application is necessary to ensure the high quality of the ordered product, delivery or service. Making an order for intellectual services,...
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Prototype design and development of low-load-roof photovoltaic modules for applications in on-grid systems
PublicationFour prototypes of lightweight photovoltaic modules for applications in on-grid systems have been designed, developed, manufactured and tested for compliance with relevant IEC standards. Selected, commercially available materials characterized by thermogravimetry, differential scanning calorimetry, dilatometry, scanning electron microscopy and nanoindentation technique were used in frameless, adhesively-bonded sandwich-structures...
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S&YP + Mentors + Peace + Love = Science and Growing
PublicationIn this extraordinarily difficult time, we understand better that only peace, love, and cooperation are the keys to growing in technology for humanity. Let us learn from our mentors how they grow from their hard work and international cooperation. Thanks to Prof. Giuseppe Buja and Prof. Zbigniew Krzemiński, we have unique schools of adjustable speed drives that are helping people convert electrical to mechanical power and vice...
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Influence of Property Division on the Technical Condition of a Building
PublicationIn this article, the correlation between a technical condition of a building and property division is analyzed and assessed. In the course of the usage of a building, the process of its degradation and the increase in the demands of property occupants can be observed. There is a direct connection between the difficult technical condition of a building and the fragmentation of the ownership structure. Although not considered in...
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Polymers for burn dressings and skin substitutes
PublicationSkin burns belong to the group of the most complex injuries due to convoluted skin structure which includes nerve cells, muscles, sweat and sebaceous glands and blood vessels. Both on the market and at the research stage, there are many different dressing and skin substitutes proposals that utilize various materials and active substances. This chapter focuses on summarizing and describing the most popular polymer-based commercial...
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Direct determination of paraquat herbicide by square-wave voltammetry by two-step transfer mechanism at heterogeneous boron-doped carbon nanowall electrodes
PublicationBoron-doped carbon nanowalls (B:CNW) versus boron-doped diamond (BDD) materials were investigated for the effective electrochemical detection of highly toxic herbicide paraquat (PQ). Depending on the surface morphology and functional groups of BDD and B:CNWs, the electrochemical absorption and detection of the target analyte PQ revealed different detection mechanisms. The surface absorption mechanism was mainly observed for BDD,...
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Fermi-liquid behavior of binary intermetallic compounds Y3 M (M = Co, Ni, Rh, Pd, Ir, Pt)
PublicationA series of polycrystalline samples of Y3 M (M = Co, Ni, Rh, Pd, Ir, Pt), intermetallic binary compounds were synthesized by the arc-melting method. Powder x-ray diffraction (pXRD) confirmed the orthorhombic cementite-type crystal structure and allowed for the estimation of the lattice parameters. Physical properties were investigated by means of electrical resistivity and heat capacity measurements between 1.9 K and 300 K. All...
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Fine-Tuning the Photocatalytic Activity of the Anatase {1 0 1} Facet through Dopant-Controlled Reduction of the Spontaneously Present Donor State Density
PublicationThe present study highlights the importance of the net density of charge carriers at the ground state on photocatalytic activity of the faceted particles, which can be seen as a highly underexplored problem. To investigate it in detail, we have systematically doped {1 0 1} enclosed anatase nanoparticles with Gd3+ ions to manipulate the charge carrier concentration. Furthermore, control experiments using an analogical Nb5+ doped...
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Electrochemical investigations on corosivity of de-icing liquids for railway infrastructure
PublicationThe paper presents the results of electrochemical tests of the de-icing fluid for railway infrastructure. DC and AC electrochemical tests were performed to determine the corrosion rates of structural steel, cast iron and aluminium in the newly produced fluid. The results were compared with the corrosion rates of the same materials in the fluid without corrosion inhibitors. The obtained test results indicate a low corrosion risk...
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Analysis of ring cracks in ceramic rolling elements using the boundary element method
PublicationCeramic materials have been increasingly used in bearing technology for over a dozen years. This is due to the characteristic properties of ceramic materials such as: high hardness, corrosion resistance, the possibility of use in aggressive chemical environments, as well as due to the lower specific weight compared to steel materials. However, the use of ceramic materials is connected with many limitations. The main disadvantages...
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Electrical and mechanical characterization of two-phase alloys by means of scanning probe microscopy in dynamic impedance spectroscopy mode
PublicationDynamic impedance spectroscopy, evaluated for measuring non-stationary systems, was used in combination with scanning probe microscope. Using this approach, localized impedance measurements in the AFM contact mode could be carried out. Additionally, impedance–force curves were made at each phase of investigated materials to illustrate the relation between impedance and the force applied to a probe. Therefore, correlation of electrical...
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THE PROTECTIVE MEASURES AGAINST SARS-COV-2 INFECTION IN THE SEAFOOD COMPANY FROM THE PERSPECTIVE OF THE EMPLOYEES
PublicationPurpose: To identify and discuss the protective measures implemented to prevent SARS-CoV-2 infection among employees. Design/methodology/approach: The four-stage course of research. Case study and structured interviews with all employees, directly and indirectly, involved in food processing. Research questions: (R1) What measures have been taken to prevent the risk of infection among employees? (R2) What activities and responsibilities...
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Boron-Enhanced Growth of Micron-Scale Carbon-Based Nanowalls: A Route toward High Rates of Electrochemical Biosensing
PublicationIn this study, we have demonstrated the fabrication of novel materials called boron-doped carbon nanowalls (B:CNWs), which are characterized by remarkable electrochemical properties such as high standard rate constant (k°), low peak-to-peak separation value (ΔE) for the oxidation and reduction processes of the [Fe(CN)6]3–/4– redox system, and low surface resistivity. The B:CNW samples were deposited by the microwave plasma-assisted...
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Badanie właściwości czujników wilgotności na bazie nanocząstek tlenku cynku
PublicationW celu pomiaru wilgotności szeroko stosowane są czujniki elektryczne. Warstwą czynną, zmieniającą swoje właściwości pod wpływem pary wodnej, stanowią najczęściej materiały ceramiczne lub polimerowe. Tlenek cynku jest jednym z materiałów ceramicznych będących dobrym kandydatem do zastosowania go jako warstwy czynną w czujnikach wilgotności. W tej pracy przedstawiono wyniki badań właściwości struktur czujnikowych z warstwą tlenku...
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Synthesis of highly crystalline photocatalysts based on TiO2 and ZnO for the degradation of organic impurities under visible-light irradiation
PublicationA TiO2–ZnO binary oxide system (with molar ratio TiO2:ZnO = 8:2) was synthesized by a hydrothermal method, assisted by calcination at temperatures of 500, 600 and 700 °C, using zinc citrate as the precursor of ZnO. The morphology (SEM, TEM), crystalline structure (XRD, Raman spectroscopy), diffuse reflectance spectra (DRS), chemical surface composition (EDXRF), porous structure parameters (low-temperature N2 sorption) and characteristic...
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Self-organized multilayered graphene-boron doped diamond hybrid nanowalls for high performance electron emission devices
PublicationCarbon nanomaterials like nanotubes, nanoflakes/nanowalls and graphene have been used as electron sources due to their superior field electron emission (FEE) characteristics. Nevertheless, these materials show poor stability and a short lifetime, preventing them from being used in practical device applications. The intention of this study was to find an innovative nanomaterial, possessing both high robustness and reliable FEE behavior....
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Novel Low-Loss Substrates for 5G Applications
PublicationThis paper presents a feasibility study of a new type of microwave low-loss dielectric substrates for 5G network applications. The new substrate materials are composites of polypropylene and high-dielectric-constant micro-ceramics. This combination is expected to form a very low-loss dielectric material at low fabrication cost. Two substrate samples with different dielectric properties are fabricated and their characteristics at...
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Closing the gap – the opportunity for sustainability and smart transition in the Central and East Europe countries
PublicationFor almost half a century the countries of CEE were part of- or were remaining under the influence of- the Soviet Union what caused gaping difference in the starting line towards sustainability. Here the prefabricated concrete blocks of flats were being built at the scale unseen in the western countries. Those buildings, approximately a quarter of the residential market, are in a structurally sound condition to last another five...
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Regeneration of marine engine valves using laser surfacing
PublicationThis article presents an analysis of the applicability of laser surfacing of the exhaust valve face of a marine diesel engine using cobalt-based powder. After preparation by machining, the selected valves were subjected to laser surfacing using a high-power ROFIN DL020 laser. The EuTroLoy 16012 powder was used in the surfacing process. One of the valves was cut and subjected to metallographic examination and hardness measurements,...
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Experimental Investigations of Fracture Process Using DIC in Plain and Reinforced Concrete Beams under Bending
PublicationThe fracture behaviour of concrete and reinforced concrete beams under quasi-static three-point bending was comprehensively investigated with experiments at laboratory scale. The eight various concrete mixes were tested. The influence of the shape, volume and size of aggregate particles and reinforcement on concrete fracture under bending was studied. Displacements on the surface of concrete beams were measured by means of the...
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Flicker Noise in Resistive Gas Sensors—Measurement Setups and Applications for Enhanced Gas Sensing
PublicationWe discuss the implementation challenges of gas sensing systems based on low-frequency noise measurements on chemoresistive sensors. Resistance fluctuations in various gas sensing materials, in a frequency range typically up to a few kHz, can enhance gas sensing by considering its intensity and the slope of power spectral density. The issues of low-frequency noise measurements in resistive gas sensors, specifically in two-dimensional...
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New σ-phases in the Nb–X–Ga and Nb–X–Al systems (X = Ru, Rh, Pd, Ir, Pt, and Au)
PublicationPreviously unreported σ-phases in the ternary niobium-based systems Nb–X–Ga for X = Ru, Rh, Pd, Ir, Pt, Au, and Nb–X–Al for X = Ir, and Pt are presented, prepared by arc-melting followed by annealing at 1000 °C for 1 week. The phases are primitive tetragonal (P42/mnm, no. 136) with lattice parameters of a = 9.8336(2)–9.9432(1) Å and c = 5.1098(1)–5.1718(1) Å. Refinements of the single crystal X-ray diffraction data for the Ru and...
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Effect of sintering temperature on electrochemical performance of porous SrTi1-xFexO3-δ (x = 0.35, 0.5, 0.7) oxygen electrodes for solid oxide cells
PublicationThis work evaluates the effects of the sintering temperature (800 °C, 900 °C, 1000 °C) of SrTi1-xFexO3-δ (x = 0.35, 0.5, 0.7) porous electrodes on their electrochemical performance as potential oxygen electrode materials of solid oxide cells. The materials were prepared by a solid-state reaction method and revealed the expected cubic perovskite structure. After milling, the powders were characterised by a sub-micrometre particle...
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Auxetic foams
PublicationThis paper presents a method of producing auxetic polyurethane foams (PUFs) and their unique properties. The experience was based on a synthesis of traditional flexible polyurethane foam and thermal conversion to auxetic foam. The foam specimens were transformed from conventional Poisson's ratio to auxetic (negative Poisson's ratio) [1]. Basic research was performed to determine the mechanical properties and cell structure. Auxetic...
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Timber - material of the future. Examples of small wooden architecture structures.
PublicationThe aim of this article is to present various types of wood-based products, classified as engineered timber, while specifying the implications of their structural properties for their forms. Timber is used as a construction material due to its fire resistance, good structural characteristics and insulating properties. The advent of new technologies of wood processing and wood-based materials production has converted timber into...
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Thermodynamics of solid phases containing rare earth oxides
PublicationRare earth elements (RE) are incorporated into a large variety of complex oxide phases to provide tailored mechanical, electrical, optical, and magnetic properties. Thermodynamics control phase stability, materials compatibility in use, corrosion, and transformation. This review presents, in one compilation, the thermodynamic properties of a large number of such materials and discusses systematic trends in energetics and the factors...
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Wpływ liczby mieszkańców na obliczenia ilości ścieków w projektowaniu kanalizacji sanitarnej
PublicationZmiana sposobu rozliczania zużycia wody, promocja wodooszczędnych technologii oraz uszczelnienie kanałów wyraźnie wpłynęły na ilość odprowadzanych do kanalizacji ścieków. Obecnie stwierdzić można, że opracowania z lat 70-tych XX wieku podają zawyżone wskaźniki odpływu ścieków, skutkiem czego są problemy eksploatacyjne. Bez wątpienia, prawidłowe zaprojektowanie kanalizacji sanitarnej to zadanie trudne, wymagające między innymi prawidłowego...
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Nowe substancje psychoaktywne CZ. II. SYNTETYCZNE KANNABINOIDY - CHARAKTERYSTYKA, METODY OZNACZANIA I WYZWANIA ANALITYCZNE
PublicationDo nielegalnego obrotu co roku trafiają nowe związki o działaniu psychoaktywnym. Dostęp do takich substancji nie jest trudny, gdyż są one łatwo dostępne w wielu krajach, głównie w sklepach internetowych. Ponadto, organy ścigania i wymiar sprawiedliwości nie nadążają z wprowadzaniem tych substancji na listy substancji zakazanych przez co ich kontrola jest bardzo utrudniona. Syntetyczne kannabinoidy to grupa związków chemicznych,...
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Improved methods for stator end winding leakage inductance calculation
PublicationCalculating the stator end-winding leakage inductance, taking into account the rotor, is difficult due to the irregular shape of the end-winding. The end-winding leakage may distribute at the end of the active part and the fringing flux of the air gap. The fringing flux belongs to the main flux but goes into the end-winding region. Then, not all the magnetic flux occurring in the end region is the end-winding leakage flux. The...
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Badania systemów powstrzymujących pojazd przed wypadnięciem z drogi - cz. I
PublicationTransportation systems are designed and used so as to effectively and safely relocate people, goods and services. Despite this there are numerous hazards that disrupt or damage these systems. Risks such as extreme weather conditions, terrorist threats, landsliders or earthquakes are difficult to predict, manage and mitigate. One of the hazards for transportation systems are accidents, and their impact on the transport functioning...
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Measurement of complex refractive index of human blood by low-coherence interferometry
PublicationIn this article, the usefulness of the optical technique for measurements of blood complex refractive index has been examined. Measurement of optical properties of human blood is difficult to perform because of its nonuniform nature. However, results of my investigation have shown the usefulness of low-coherencei nterferometry for measurement complex refractive index of human blood. Furthermore, mathematical analysis of spectrum...
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Superhydrophobic sponges based on green deep eutectic solvents for spill oil removal from water
PublicationThe paper described a new method for crude oil-water separation by means of superhydrophobic melamine sponges impregnated by deep eutectic solvents (MS-DES). Due to the numerous potential of two-component DES formation, simple and quick screening of 156 non-ionic deep eutectic solvents using COSMO-RS (Conductor-like Screening Model for Real Solvents) computational model was used. DES which were characterized by high solubility...
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The influence of the Cu2O deposition method on the structure, morphology and photoresponse of the ordered TiO2NTs/Cu2O heterojunction
PublicationThe increased interest in highly ordered titania structures exhibiting tubular shape that could be directly formed onto the stable substrate is related with the intensive research on their modification enabling absorption of light within the wide solar spectrum and its further conversion into electric or chemical energy. Among others, formation of uniform 3D heterojunctions based on the TiO2 nanotubes attracts attention since porous...
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Synthesis and characterization of biopolyols through biomass liquefaction of wood shavings and their application in the preparation of polyurethane wood composites
PublicationThe sustainability of production systems in wood processing, wood industry, and wooden waste disposal is an important issue for European industry and society. Proper development of products based on renewable wood resources gives an opportunity to provide materials with long-term environmental, social, and economic sustainability. This study aims to establish a new way of forestry and agricultural waste materials utilization by...
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Linear viscoelastic transversely isotropic model based on the spectral decomposition of elasticity tensors
PublicationThe linear viscoelasticity is still a useful model in the engineering for studying the behavior of materials loaded with different loading rates (frequencies). Certain types of materials reveal also an anisotropic behavior: fiber reinforced composites, asphalt concrete mixtures, or wood, to name a few. In general, researchers try to identify experimentally the dependence of engineering constants like: directional Young’s moduli...
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Morphology of bio-based polyurethane composites filled by mer-cerized or silanized natural fibres
PublicationBio-composites are materials which possess unique properties and undergo biodegra-dation under specific conditions. Bio-composites belong to the group of materials produced with the use of renewable raw materials. They contain reinforcement, mainly in the form of natural fiber, which has high stiffness and resistance; filler powders are less frequently used. Significant features of natural fibers are elongation, density, thermal...
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TOXICOLOGICAL ASSESSMENT OF FOOD PACKAGES EXTRACTS
PublicationIn the scientific literature related to the widely understood issue of packaging materials designed to have contact with food (Food Contact Materials – FCM) there is much information on raw materials used for their production, their physiochemical properties, types and parameters. There is also a great number of publications on the management and disposal of used packaging. Unfortunately, not much attention is given to the matters...
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Laser-Induced Graphitization of Polydopamine on Titania Nanotubes
PublicationSince the discovery of laser-induced graphite/graphene, there has been a notable surge of scientific interest in advancing diverse methodologies for their synthesis and applications. This study focuses on the utilization of a pulsed Nd:YAG laser to achieve graphitization of polydopamine (PDA) deposited on the surface of titania nanotubes. The partial graphitization is corroborated through Raman and XPS spectroscopies and supported...
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Boron doped Nanocrystalline Diamond-Carbon Nanospike Hybrid Electron Emission Source
PublicationElectron emission signifies an important mechanism facilitating the enlargement of devices that have modernized large parts of science and technology. Today, the search for innovative electron emission devices for imaging, sensing, electronics, and high-energy physics continues. Integrating two materials with dissimilar electronic properties into a hybrid material is an extremely sought-after synergistic approach envisioning a...
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Reliable renewable energy – application of electrochemical capacitors for electrical energy storage
PublicationThis paper presents electrical energy storage devices such as electrochemical capacitors, their principle of operation and electrode materials most commonly used in their manufacturing technology. Moreover, our research on development of new nanocomposite materials based on multi-walled carbon nanotubes and conducting polymer is shown. Additionally, the possibility and advantages of application of supercapacitors for accumulation...
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Enhanced visible light-activated gas sensing properties of nanoporous copper oxide thin films
PublicationMetal oxide gas sensors are popular chemoresistive sensors. They are used for numerous tasks, including environmental and safety monitoring. Some gas-sensing materials exhibit photo-induced properties that can be utilized for enhanced gas detection by modifying the sensor selectivity and sensitivity when illuminated by light. Here, we present the gas sensing characteristics of highly nanoporous Cu2O thin films towards both electrophilic...
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Intelligent Material Actuators and Their Applications for Structural Dynamic Control
PublicationThe paper presents an application of inteligent materials to vibration control of structures.
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Antibacterial Porous Systems Based on Polylactide Loaded with Amikacin
PublicationThree porous matrices based on poly(lactic acid) are proposed herein for the controlled release of amikacin. The materials were fabricated by the method of spraying a surface liquid. Description is given as to the possibility of employing a modifier, such as a silica nanocarrier, for prolonging the release of amikacin, in addition to using chitosan to improve the properties of the materials, e.g., stability and sorption capacity....
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Impact of strontium non-stoichiometry of SrxTi0.3Fe0.7O3-δ on structural, electrical, and electrochemical properties for potential oxygen electrode of intermediate temperature solid oxide cells
PublicationThis work presents the results of a comprehensive study on the impact of the A-site non-stoichiometry of SrxTi0.3Fe0.7O3-δ (x = 0.90, 0.95, 1.00, 1.05) ceramics on their physicochemical properties. The materials were fabricated by the conventional solid-state reaction method and their structure was determined by X-ray diffractometry, X-ray photoelectron spectroscopy and electron microscopy. Their sintering and thermal expansion...
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Production of new non-matrix reference material of ethene
PublicationThe main objective of the research is to produce new non-matrix reference materials of ethene. The study are based on thermal decomposition of surface compound chemically bonded with the surface of glass fibers coated with thin layer of aluminum. Positivehomogeneity test, stability test and organization of inter-laboratory comparison are leading to find new non-matrix reference materials which are indispensable tools in the analysis...
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Właściwości elektryczne szkło-ceramiki zawierającej ferroelektryczną fazę BiV
PublicationKompozyty szklano - ceramiczne zawierające nanokryształy posiadają właściwości fizyczne, które nie są możliwe do uzyskania w innych materiałach. Dzięki możliwości wytworzenia szkło - ceramik posiadających kryształy o różnej wielkości (nano, mikro...) i różnorodnego typu, można w istotny sposób kontrolować właściwości elektryczne takich materiałów. Stała dielektryczna faz ferroelektrycznych jest bardzo wrażliwa na zmiany rozmiarów...
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Nowe monomery pochodzenia roślinnego w syntezie termoplastycznych elastomerów poliuretanowych
PublicationJak dotychczas w syntezie termoplastycznych elastomerów poliuretanowych (TPU) są powszechnie wykorzystywane surowce pochodzenia petrochemicznego. Sytuacja jednak zmienia się dynamicznie i w wielu gospodarkach świata widoczne są już trendy, polegające na coraz większym wykorzystaniu substancji pochodzenia roślinnego w produkcji surowców, np. glikoli, izocyjanianów czy polioli, jako zamienników analogów syntetycznych. Praca obejmuje...