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Search results for: surface layer
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Study of Photovoltaic Devices with Hybrid Active Layer
PublicationThe aim of this work is to present the influences of composition of the material andmanufacturing technology conditions of the organic photovoltaics devices (OPv) with the organicand hybrid bulk heterojunction on the active layers properties and cells performance. The layers wereproduced by using small molecular compounds: the metal-phthalocyanine (MePc) and perylenederivatives (PTCDA) and the titanium dioxide (TiO2) nanoparticles....
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Investigation of the Few‐Layer Black Phosphorus Degradation by the Photonic Measurements
PublicationFew-layer black phosphorus (FLBP) is a 2D material that gains worldwide interest for its possible applications, mainly in electronics and optoelec-tronics. However, as FLBP is prone to a degradation process under envi-ronmental conditions, there is a need for a monitoring method allowing investigation of its surface quality. Among many techniques, optoelectronic ones have unique advantages of fast response, non-contact, and non-invasive...
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Nanotubular Oxide Layer Formed on Helix Surfaces of Dental Screw Implants
PublicationSurface modification is used to extend the life of implants. To increase the corrosion resistance and improve the biocompatibility of metal implant materials, oxidation of the Ti-13Nb- 13Zr titanium alloy was used. The samples used for the research had the shape of a helix with a metric thread, with their geometry imitating a dental implant. The oxide layer was produced by a standard electrochemical method in an environment of...
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Electrophoretic Deposition and Characteristics of Chitosan–Nanosilver Composite Coatings on a Nanotubular TiO2 Layer
PublicationThe surface treatment of titanium implants has been applied mainly to increase surface bioactivity and, more recently, to introduce antibacterial properties. To this end, composite coatings have been investigated, particularly those based on hydroxyapatite. The present research was aimed at the development of another coating type, chitosan–nanosilver, deposited on a Ti13Zr13Nb alloy. The research comprised characterization of the...
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Spectroscopic Optical Coherence Tomography for Thin Layer and Foil Measurements
PublicationThe main goal of this research was to assess if it is possible to evaluate the thickness of thin layers (both thin films on the surface and thin layers below the surface of the tested object) and foils using optical coherence tomography (OCT) for thickness assessment under the resolution of the standard commercially available OCT measurement system. In the proposed solution, light backscattered from the evaluated thin layer has...
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Thermal and hydraulic phenomena in boundary layer of minijets impingement on curved surfaces
PublicationPresented work considers flow and thermal phenomena occurring during the single minijet impingement on curved surfaces, heated with a constant heat flux, as well as the array of minijets. Numerical analyses, based on the mass, momentum and energy conservation laws, were conducted, regarding single phase and two-phase simulations. Focus was placed on the proper model construction, in which turbulence and boundary layer modeling...
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Mechanical Behavior of Bi-Layer and Dispersion Coatings Composed of Several Nanostructures on Ti13Nb13Zr Alloy
PublicationTitanium implants are commonly used because of several advantages, but their surface modification is necessary to enhance bioactivity. Recently, their surface coatings were developed to induce local antibacterial properties. The aim of this research was to investigate and compare me-chanical properties of three coatings: multi-wall carbon nanotubes (MWCNTs), bi-layer composed of an inner MWCNTs layer and an outer TiO2 layer, and...
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The Use of Direct Shear Test for Optimization of Interlayer Bonding Under a Poroelastic Layer
PublicationPoroelastic Road Surfaces (PERS) are characterised by porous structure with air void content of 20% or higher and stiffness almost 10 times lower than that of a standard asphalt course. Such properties enable noise reduction by up to 12 dB in comparison to SMA 11 mixture. However, the disadvantage of a poroelastic pavement is its low durability, which partially results from delamination from the lower layer. The paper aims to investigate...
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Titania Nanotubes/Hydroxyapatite Nanocomposites Produced with the Use of the Atomic Layer Deposition Technique: Estimation of Bioactivity and Nanomechanical Properties
PublicationTitanium dioxide nanotubes/hydroxyapatite nanocomposites were produced on a titanium alloy (Ti6Al4V/TNT/HA) and studied as a biocompatible coating for an implant surface modification. As a novel approach for this type of nanocomposite fabrication, the atomic layer deposition (ALD) method with an extremely low number of cycles was used to enrich titania nanotubes (TNT) with a very thin hydroxyapatite coating. X-ray diffraction (XRD)...
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Double layer adhesive silicone dressing as a potential dermal drug delivery film in scar treatment
PublicationThe present studies focused on the evaluation of design of an adhesive silicone film intended for scar treatment. Developed silicone double layer film was examined in terms of its future relevance to therapy and applicability on the human skin considering properties which included in vitro permeability of water vapor and oxygen. In order to adapt the patches for medical use in the future there were tested such properties as...
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Tuning Electrochemical Performance by Microstructural Optimization of the Nanocrystalline Functional Oxygen Electrode Layer for Solid Oxide Cells
PublicationFurther development of solid oxide fuel cell (SOFC) oxygen electrodes can be achieved through improvements in oxygen electrode design by microstructure miniaturisation alongside nanomaterials implementation. In this work, improved electrochemical performance of an La0.6Sr0.4Co0.2Fe0.8O3-d (LSCF) cathode was achieved by the controlled modification of the La0.6Sr0.4CoO3-d (LSC) nanocrystalline interlayer introduced between a porous...
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Effect of hybrid modification by ceramic layer formation in MAO process and laser remelting on the structure of titanium bio-alloy Ti13Nb13Zr
PublicationTo improve the biological properties of titanium alloy Ti13Nb13Zr, hybrid modifications involving micro-arc oxidation (MAO) and Nd: YAG laser remelting were carried out in two combinations. The first consisted of laser modification before the production of the ceramic layer by the micro-arc oxidation process, and the second combination involved Nd: YAG laser modification after the MAO process. The creation of developed surface...
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Influence of vacuum sublimation deposited metal layer thickness on metrological parameters of the amperometric gas sensor with Nafion membrane
PublicationThe paper presents the results of investigation on an influence of vacuum sublimation deposited platinum layer thickness on the signal, sensitivity and response time of a prototype of sulphur dioxide sensor with Nafion membrane. The working electrode was made by vacuum sublimation deposition of platinum on a surface of Nafion membrane. Pt layers deposited changed an initial structure of Nafion membrane and that phenomenon was utilized...
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The effect of beech wood (Fagus sylvatica L.) steaming process on the colour change versus depth of tested wood layer
PublicationThe results of experimental research on the colour changes of beech wood at different depths of the tested layer are presented. Beech wood (Fagus sylvatica L.) dried in a conventional kiln was tested. Half of the wood samples were steamed prior to the drying process. Colour changes were measured at various depths after the face milling process was used to remove the material to expose to the deeper surface. The colour changes were...
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Multi-layer graphene oxide alone and in a composite with nanosilica: Preparation and interactions with polar and nonpolar adsorbates
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Structural and dynamic properties of water within the solvation layer around various conformations of the glycine-based polypeptide
PublicationSeveral conformations of the solvated glycine-based polypeptides were investigated using molecular dynamics simulations. Some properties of water in the neighbouring space around these molecules were investigated. It was found, that water forms a well-defined layer - the first solvation shell - around the peptide molecule, and thickness of this layer is independent of the peptide structure, and it equals to approximately 0.28 nm....
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Structural and Dynamic Properties of Water within the Solvation Layer around Various Conformations of the Glycine-based Polypeptide
PublicationSeveral conformations of the solvated glycine-based polypeptides were investigated using molecular dynamics simulations. Some properties of water in the neighboring space around these molecules were investigated. It was found that water forms a well-defined layer—the first solvation shell—around the peptide molecule, and thickness of this layer is independent of the peptide structure and is equal to approximately 0.28 nm. Within...
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SAXS examination of the water evaporation process from silica materials coated with a polysaccharide–polyimine copolymer layer
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Density functional LCAO calculations of vibrational modes and phonon density of states in the strained single-layer phosphorene
PublicationThe paper presents an investigation of phosphorene under axial strain on the phonon density of states and vibrational modes. The studies were performed by means of density functional theory (DFT) within the linear combination of atomic orbitals (LCAO). The strained models were constructed using optimised supercell techniques. The vibrational mode spectra were estimated for strains applied for both the zigzag and armchair directions...
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Enhanced stability of electrochemical performance of few-layer black phosphorus electrodes by noncovalent adsorption of 1,4-diamine-9,10-anthraquinone
PublicationIn this paper, the novel noncovalent functionalisation strategy of few-layer black phosphorus by 1,4-diamine-9,10-anthraquinone electrode was proposed and studied. The degradation of few-layer black phosphorus under exposure to oxygen and water is a significant obstacle to its use as an electroanalytical electrode. The anthraquinone compound adsorbed at black phosphorus flakes results in improved prevention of the phosphorus surface...
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Thin layer of ordered boron-doped TiO2 nanotubes fabricated in a novel type of electrolyte and characterized by remarkably improved photoactivity
PublicationThis paper reports a novel method of boron doped titania nanotube arrays preparation by electrochemical anodization in electrolyte containing boron precursor – boron trifluoride diethyl etherate (BF3 C4H10O), simultaneously acting as an anodizing agent. A pure, ordered TiO2 nanotubes array, as a reference sample, was also prepared in solution containing a standard etching compound: ammonium fluoride. The doped and pure titania...
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Reactions on the surface of the implant under the influence of biofilm
PublicationThe contact of a biomaterial with the biological environment in in vitro and in vivo tests leads to the production of a particular ecosystem in which the active roles perform both, the material surface and the extracellular matrix protein forming a biofilm. Proteins affect cell and bacteria adhesion processes, biological activity of cells and activation of inflammatory response.The knowledge of the reaction mechanisms active on...
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The Influence of Laser Alloying of Ti13Nb13Zr on Surface Topography and Properties
PublicationThe laser alloying is a continually developing surface treatment because of its significant and specific structuration of a surface. In particular, it is applied for Ti alloys, being now the most essential biomaterials` group for load-bearing implants. The present research was performed on the Ti13Nb13Zr alloy subject to laser modification in order to determine the treatment effects on surface topography and its some mechanical...
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Visible light activity of pulsed layer deposited BiVO4/MnO2 films decorated with gold nanoparticles: The evidence for hydroxyl radicals formation
PublicationThin films containing BiVO4 and MnO2 deposited on FTO and modified by Au nanoparticles were studied towards their photoelectrochemical and photocatalytical activities in an aqueous electrolyte. Electrodes were prepared by the pulsed laser deposition (PLD) method. The surfactant-free ablation process was used for preparation of the gold nanoparticles (GNP) water suspension. Obtained layers of varied thicknesses (27–115 nm) were...
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The Issue of Shading Photovoltaic Installation Caused by Dust Accumulation on the Glass Surface
PublicationThe issue of accumulation of dust and other pollutants on the surface of photovoltaic modules was thoroughly analysed over the years. One of the first surveys in this field of knowledge linked pollutant accumulation on the module surface with transmittance loss of its glass covering, which leads to lessened amount of solar radiation reaching solar cells. First stage of this accumulation process is linear transparency loss, and second...
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Role of surface recombination in perovskite solar cells at the interface of HTL/CH3NH3PbI3
PublicationIn order to achieve the highest performance of organometal trihalide perovskite solar cells, it is required to recognize the dominant mechanisms which play a key role in a perovskite material. In the following studies, we have focused on the interfacial recombination between the hole transporting layer (HTL) and the perovskite CH3NH3PbI3 in solar cell devices with p–i–n architecture. It has been shown that Cu:NiOx : used as HTL...
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Influence of Surface Laser Treatment on Mechanical Properties and Residual Stresses of Titanium and its Alloys
PublicationSurface modification of the titanium and its alloys used in implantology with a long-pulse laser can change the surface topography, but it also leads to changes in the stress sign and magnitude in the resulting subsurface layer. The presented research was aimed at evaluating the state of stress after laser remelting with the Nd:YAG laser of pre-etched titanium alloys Ti6Al4V and Ti13Nb13Zr and pure titanium. The obtained surface...
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Layer-by-layer polymer deposited fabrics with superior flame retardancy and electrical conductivity
PublicationSmart and multifunctional textiles and fabrics are progressively developing, such that multifunctional fabrics are becoming more widespread. We elaborated herein multi-layered flax fabrics with superior flame retardancy and conductivity, which revealed fireproof feature while keeping conductivity during burning. The flax fabric was reinforced by layer-by-layer (LbL) deposition of sodium polyacrylate (SPA), polyethylenimine (PEI),...
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Antagonist adhesion effects due to variable substrate surface
PublicationThe effects of variability of intrinsic adhesion within a joint have been studied using a single cantilever beam (SCB) test. Fracture energy was found not to be a simple function of relative areas of 2 surface pre-treatments: a 'weak' zone decreased strength more than expected from simple, additive considerations. By severing the adhesive along the strong-weak transition, fracture energy increased.The prior antagonist effect appears...
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Pressure field in a plane layer
PublicationPraca prezentuje wyniki badań teoretycznych i numerycznych zagadnienia przejścia fal płaskich przez warstwę. Omówiono zagadnienie tworzenia i rozchodzenia się fal w poszczególnych warstwach. Zaproponowano model matematyczny opisujący zmiany ciśnienia wewnątrz warstwy. Analizowano ciśnienie wewnątrz warstwy, fale bieżące i odbite wewnątrz warstwy oraz w ośrodku otaczającym. Przedstawiono wyniki badań numerycznych.
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Selected aspects of the surface quality of the wooden elements after planing
PublicationThe quality of the surface of wooden elements, that have been planed, has got a crucial meaning in the whole production process flow, since the obtained effects affect the quality of wooden surface after painting. The emergence of defects in most cases causes need to qualify workpiece as a scrap part or additional work activity must be done. In the paper selected results of the investigation of the effect of the cutting tool wear...
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Low-power microwave-induced fabrication of functionalised few-layer black phosphorus electrodes: A novel route towards Haemophilus Influenzae pathogen biosensing devices
PublicationIn this paper, various passivation schemes were applied at few-layer black phosphorus (FLBP) to achieve covalent functionalisation with 4-azidobenzoic acid, improving its electrochemical response intended for analytical and biosensing applications. The thermal and microwave assisted modification procedures in toluene and dime-thylformamide resulted in high reversibility of reactions on functionalised FLBP using a ferricyanide/ferrocya-nide...
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Molecular dynamics study on the role of solvation water in the adsorption of hyperactive AFP to the ice surface
PublicationUsing 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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Surface and Corrosion Properties of AA6063-T5 Aluminium Alloy in Molybdate-containing Sodium Chloride Solutions
PublicationCorrosion properties of aluminium alloy AA6063-T5 were investigated in molybdate-containing NaCl solutions. Electrochemical, microscopic, and spectroscopic experiments were utilized to examine the mechanism of corrosion inhibition by molybdates. SEM-EDX, magnetic force, and intermodulation electrostatic force microscopy data suggested that the inhibition initiation preferentially occurred over Fe-rich cathodic IMPs. Spectroscopic...
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The use of Response Surface Methodology for reliability estimation of composite engineering structures
PublicationStability loss is one of the key issues in the analysis of shells made of composite materials. This paper aims at finding the variation of the critical or limit value of the load resulting from geometric imperfections. An axially compressed 16-layer cylindrical panel model is considered. The imperfections of the panel are simulated as random fields. The parameters of these fields are used as the basic variables of the reliability...
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The silver layers in fiber-optic sensors
PublicationIn this paper a method of application of the silver layers on the surface of an optical fiber was proposed. The optical properties and surface quality of the silver layer was examined by optical microscopy. The reflection and transmission of the sample were investigated. To evaluate the silver mirror it was placed in a fiber optic Fabry-Perot interferometer and the quality of the spectra was analyzed. The commercial mirror was...
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Corrosion and Cavitation Resistances of Low Alloy Steel After Frictional-Mechanical Treatment
PublicationPaper presents the results of the studies of wear, corrosion and cavitation resistances of the S355J2 low alloy medium carbon steel subjected to surface modification by friction-mechanical treatment, as tested in sea water simulated solution. To evaluate the effect of the surface treatment, the comparative studies of the corrosive properties of the steel before and after treatment have been considered. The treatment due to a severe...
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Anti-plane shear waves in an elastic strip rigidly attached to an elastic half-space
PublicationWe consider the anti-plane shear waves in a domain consisting of an infinite layer with a thin coating lying on an elastic half-space. The elastic properties of the coating, layer, and half-space are assumed to be different. On the free upper surface we assume the compatibility condition within the Gurtin–Murdoch surface elasticity, whereas at the plane interface we consider perfect contact. For this problem there exist two possible...
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Variable Temperature Spectroscopic Ellipsometry as a Tool for Insight into the Optical Order in the P3HT:PC70BM and PC70BM Layers
PublicationTwo combined ellipsometric techniques—variable angle spectroscopic ellipsometry (VASE) and variable temperature spectroscopic ellipsometry (VTSE)—were used as tools to study the surface order and dielectric properties of thin films of a poly(3-hexylthiophene-2,5-diyl) (P3HT) mixture with a fullerene derivative (6,6-phenyl-C71-butyric acid methyl ester) (PC70BM). Under the influence of annealing, a layer of the ordered PC70BM...
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Superconductivity in three-layer Na0.3CoO2·1.3H2O
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Analysis of nonlinear generation in bubble layer
PublicationRozważano zagadnienie liniowego i nieliniowego rozpraszania w warstwie z pęcherzykami. Badania numeryczne dotyczyły rozpraszania koherentnego i różnych własności rozchodzenia się fal wewnątrz warstwy z pęcherzykami jak odbicie od brzegu, dyspersja, tłumienie. Badania dla różnych rozkładów pęcherzyków przeprowadzono w oparciu o równanie Rayleigha-Plesseta.
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Electrochemical analysis of aluminium passive layer
PublicationZbadano proces pękania warstwy pasywnej na aluminium dla liniowo narastających naprężeń rozciągających oraz różnych warunków elektrochemicznych. Badania prowadzono w 0.1M NaCl metodą dynamicznej elektrochemicznej spektroskopii impedancyjnej przy różnych poziomach polaryzacji anodowej. Określono progową wartość naprężeń, przy której następowało zniszczenie warstwy pasywnej wskutek działania sił rozciągających.
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Superconductivity in three-layer Na0.3CoO2*1.3H2O
PublicationOdkryto nadprzewodnictwo w trójwarstwowym związku uwodnionego sodowo -kobaltowego tlenku Na0.3CoO2 * 1.3H2O. Opisany został sposób syntezy, badania strukturalne (XRD i TGA) a także badania podatności magnetycznej.
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High - voltage thin - layer fuses
PublicationZaprezentowano nową technologię i konstrukcję bezpieczników wysokonapięciowych wykorzystując technologie stosowane w mikroelektronice. Cienką warstwę topika naniesiono na quasiceramiczne podłoże. Wykonane modele bezpieczników charakteryzują się wysoką pewnością działania oraz małymi stratami I2t.
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Acoustic heating produced in the boundary layer
Publication: Instantaneous acoustic heating of a viscous fluid flow in a boundary layer is the subject of investigation. The governing equation of acoustic heating is derived by means of a special linear combination of conservation equations in the differential form, which reduces all acoustic terms in the linear part of the final equation but preserves terms belonging to the thermal mode. The procedure of decomposition is valid in a weakly...
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Modeling of nonlinear generation in a bubble layer
PublicationPraca prezentuje numeryczne podejście do zagadnienia liniowego i nieliniowego rozpraszania w warstwie z pęcherzykami. Badania numeryczne niekoherentnego rozpraszania wykonano stosując metodę Monte Carlo. Propagację i wsteczne rozpraszanie sygnałów badano w oparciu o równanie Rayleigha-Plesseta.
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Nanocrystalline cathode functional layer for SOFC
PublicationRecently, it was shown that thin functional layers introduced between an electrolyte and cathode might improve cathode performance. However, the mechanism of this improvement still needs analysis. In this paper, a thin (∼140 nm), spin-coated perovskite layer (La0.6Sr0.4Co0.2Fe0.8O3-δ) was placed between a cathode (La0.6Sr0.4Co0.2Fe0.8O3-δ) and an electrolyte (Ce0.8Gd0.2O2-δ) and the effects of this investigated. The microstructure...
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Photovoltaic phenomena in devices with perfluorozincphthalocyanine layer
PublicationThe course of photovoltaic phenomenon in organic photovoltaic cells utilizing thin layers of perfluorozincphthalocyanine was studied in few single and planar bilayer configurations. Mechanisms of photogeneration and recombination of free charge carriers were determined and active interfaces were localized. In case of single layer cells these interfaces were located at the front electrode/F16ZnPc junctions, whereas photogeneration...
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Electrocatalytic gas sensor with reference layer
PublicationIn recent years electrochemical gas sensors based on solid state electrolytes have been intensively developed. They are easy to obtain, use and relative durable. Nasicon is one of the most promising materials, which have been used in construction of gas sensors. Most of these devices work in potentiometric or amperometric mode. However, some works are dedicated to sensors working in electrocatalytic mode. Principle of operation...
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Electrocatalytic Gas Sensor with Reference Layer
PublicationThis paper presents studies of gas sensors prepared in ceramic technology with Nasicon as a solid electrolyte. Sensors work in the voltammetric mode thus based on the excitation of a sensor with a periodic potential signal while current response is recorded. The main aim is to investigate a Bi8Nb2O17 reference layer influence on sensor properties. Sensors I-V characteristics in different concentration of nitrogen dioxide have been...