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Search results for: ELEKTROCHEM IMPEDANCJA SPEKTROSKOPOWA
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Ocena systemów uziemień z wykorzystaniem pomiarów metodą udarową
PublicationW artykule zostały omówione procedury i wymagania stawiane systemom uziemień przez przepisy normalizacyjne z punktu widzenia ich skuteczności w systemie ochrony odgromowej. Podstawą tak sformułowanej oceny są pomiary z zastosowaniem metody udarowej. Metoda taka okazuje się bardzo przydatna zwłaszcza w przypadku uziemień rozległych, jakie pojawiają się we współczesnych obiektach wskutek połączenia różnych elementów uziemiających...
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Current commutation process in a ultra-fast fuse-IGBT hybrid circuit breaker.
PublicationUkład hybrydowy bezpiecznika topikowego i tranzystora IGBT umożliwia bardzo szybkie włączenie do obwodu zwarciowego impedancji ograniczającej wartość prądu. Po eksplozji krótkiego topika bezpiecznika wywołanej narastającym prądem zwarciowym wywołuje w czasie poniżej 2 ms wzrost napięcia na topiku do wartości ok.20 - 25V, po czym prąd jest komutowany do gałęzi z przyrządem półprzewodnikowym typu GTO lub IGBT. Ostateczne wyłączenie...
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Domain Reduction in Hybrid Technique for Electromagnetic Wave Scattering Problems
PublicationThis paper proposes a combination of the field matching technique, finite element method and generalized impedance matrix, the main idea of which is to reduce the computational domain by surrounding a scatterer with the smallest convex shape and applying the field matching technique. This approach can be applied for arbitrary shaped scatterers and types of materials and allows for the reduction of the computational domain. In order...
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Hybrid Analysis of Structures Composed of Axially Symmetric Objects
Publication— A hybrid method for the scattering problems in shielded and open structures is presented. The procedure is based on the combination of body-of-revolution involving finite-element methods with impedance matrix formulation and the mode-matching technique, which can be utilized for the analysis of structures with axially symmetrical scatterers. In order to confirm the validity and efficiency of the proposed approach, a few examples...
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A novel concept for tissue-metal detection and differentiation using an inductive proximity sensor
PublicationIn this paper a novel application of inductive proximity sensors for detection of living tissue by means of measurements of the coil impedance changes at different frequencies is described. The mathematical analyses utilizing Bessel function estimation include detected object size and its distance from a sensor. The main aim of this study is to prove the possibility of distinguishing between metal objects and living tissues. The...
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Oxygen partial pressure and temperature dependence of series resistance of symmetrical porous SrTi0.30Fe0.70O3 electrode on CGO substrate
Open Research DataThis dataset contains values of equivalent circuit element series resistance at different temperatures (800 °C, 700 °C, 600 °C and 500 °C) and oxygen partial pressures (100%, 80%, 50% 30%, 20%, 15%, 10%, 5%, 2.5%, 1%, and 0.3% pO2) of symmetrical SrTi0.30Fe0.70O3 electrode sintered at 800 °C. This values were obtained by fitting each measured impedance...
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Understanding the origin of high corrosion inhibition efficiency of bee products towards aluminium alloys in alkaline environments
PublicationVarious bee products were found to be efficient corrosion inhibitors of aluminium in different environments. In particular, bee pollen was found to be highly effective in alkaline electrolytes, yet its highly complex composition and possible synergistic interactions hinder determination of the compounds acting as active corrosion inhibitors. The main purpose of the following work is to investigate the effect of solvents used for...
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A Series-Inclined-Slot-Fed Circularly Polarized Antenna for 5G 28-GHz Applications
PublicationThis letter presents the design of a single-point-fed, geometrically simple circularly polarized (CP) antenna for 28 GHz Ka-band applications. The proposed antenna is based on a straight microstrip line printed on one side and coupled with the nearly square patches through a 45-degree inclined V-shape slot aperture on the other side. In order to generate circular polarization, the fundamental radiating mode is degenerated at a...
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Improved Performance of 1-Ethyl-3-Methylimidazolium Tetrafluoroborate at Steel/HCl Interface by Iodide Ions
PublicationThe corrosion and corrosion inhibition of St37 steel in 0.1 M HCl solution by 1-ethyl-3-methylimidazolium tetrafluoroborate (EMITFB) and the effect of addition of KI on the inhibitive performance of EMITFB have been examined by electrochemical [electrochemical impedance spectroscopy, potentiodynamic polarization, and dynamic electrochemical impedance spectroscopy (DEIS)] and surface examination [scanning electron microscope (SEM)...
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Novel microstrip low-pass filters with fractal defected ground structures
PublicationIn this study, three microstrip low-pass filters (LPFs) containing fractal-shaped defected ground structures have been designed and manufactured. To improve the performance of microstrip LPF, cascades of inductively coupled fractal resonators have been applied. Simultaneously, to achieve relatively constant microstrip impedance resulting in essentially low reflection losses, a modification of the strip geometry has been introduced....
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Differential analysis of dynamic immittance spectra
PublicationThis work presents a new approach to the analysis of immittance spectrograms of systems characterised by non-stationarity. The possibility of linking the evolution of the immittance response with changes in the parameters describing the system is achieved by introducing a spectrum in differential form. By using the above procedure, it becomes possible to separate elements with a dependence (or lack thereof) from an independent...
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Low-Cost Surrogate Modeling of Miniaturized Microwave Components Using Nested Kriging
PublicationIn the paper, a recently reported nested kriging methodology is employed for modeling of miniaturized microwave components. The approach is based on identifying the parameter space region that contains high-quality designs, and, subsequently, rendering the surrogate in this subset. The results obtained for a miniaturized unequal-power-split rat-race coupler and a compact three-section impedance transformer demonstrate reliability...
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A body position influence on ECG derived respiration
PublicationAn influence of a human body position on ECG derived respiration (EDR) signal is presented in the paper. Examinations were performed during deep, suspended and normal breathing for eight people in four different body positions. EDR and thoracic impedance signals were compared using correlation and standard deviation coefficients. Obtained results have shown that it is possible to monitor breath activity of people being in different...
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Reaktory elektrochemiczne w przemyśle - konstrukcja i zastosowania
PublicationZ biegiem lat reakcje elektrochemiczne przestały być postrzegane jedynie jako eksperymenty laboratoryjne lub proste baterie. Chociaż mechanizm reakcji i budowa prostych reaktorów znana jest ludzkości już od ponad 100 lat w ostatnich latach można zauważyć największy wzrost zainteresowania tą dziedziną. Nowy stale opracowywane są lepsze projekty budowy reaktorów. Modyfikacje to nie tylko rodzaje i formy materiałów, z których wykonane...
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Dynamiczna aplikacja Internetowa ASP.NET silnika indukcyjnego jako elementu wirtualnego laboratorium maszyn elektrycznych
PublicationTematem referatu jest dynamiczna aplikacja internetowa, która umożliwia symulację obwodową silnika indukcyjnego trójfazowego Sg 100 L2 z wykorzystaniem interfejsu przeglądarki WWW. Model matematyczny silnika jest zdefiniowany w tzw. osiach naturalnych i sformułowany na podstawie metody energetycznej Lagrange’a. Do implementacji modelu maszyny w aplikacji internetowej wybrano projekt typu Web Forms, który jest składnikiem środowiska...
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Lithium ion insertion into poly(3,4-ethylenedioxythiophene) films from propylene carbonate electrolytes.
PublicationPolimerowa matryca złożona z poli(3,4-etylenodioksytiofenu z poli(styrenosulfonianem) otrzymana została na drodze syntezy elektrochemicznej. Transport jonowy w matrycy polimerowej w kontakcie z węglanem propylenu zawierającym LiClO4 został scharakteryzowany za pomocą metody impedancji ac oraz chronowoltoamperometrii. Wyznaczono przewodność jonową matrycy oraz efektywne współczynniki dyfuzji dla kationu Li+. Wielkości te...
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The electrochemical response to BDD electrode functionalization with CD147 receptor
Open Research DataThis dataset contains the results of the electrochemical impedance spectroscopy (EIS) measurements of the boron-doped diamond (BDD) electrode functionalization with CD147 receptor. The functionalized electrode was then used for the electrochemical detection of the SARS-CoV-2 virus S1 protein.
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Gold nanocubic structures agglomeration when put on conductive surfaces
Open Research DataThis dataset contains Dynamic EIS results obtained for the gold electrodes with non-functionalized gold nanocubes (AuNC) deposited at its surface. The deposition was the following: 2 uL of the solvent containing CTAB as the surfactant was put on the electrode and dried, the same procedure was applied 5 times. Afterward, the electrode was immersed in...
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The electrochemical response to BDD electrode functionalization with ACE2 receptor
Open Research DataThis dataset contains the results of the electrochemical impedance spectroscopy (EIS) measurements of the boron-doped diamond (BDD) electrode functionalization with ACE2 receptor. The functionalized electrode was then used for the electrochemical detection of the SARS-CoV-2 virus S1 protein.
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The electrochemical response to BDD electrode functionalization with IgG2B receptor
Open Research DataThis dataset contains the results of the electrochemical impedance spectroscopy (EIS) measurements of the boron-doped diamond (BDD) electrode functionalization with IgG2B receptor. The functionalized electrode was then used for the electrochemical detection of the SARS-CoV-2 virus S1 protein.
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Gold nanocubic structures agglomeration when put on conductive surfaces
Open Research DataThis dataset contains Dynamic EIS results obtained for the gold electrodes with non-functionalized gold nanocubes (AuNC) deposited at its surface. The deposition was the following: 2 uL of the solvent containing CTAB as the surfactant was put on the electrode and dried, the same procedure was applied 5 times. Afterward, the electrode was immersed in...
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Electrochemical studies for screen-printed carbon electrodes (SPCE) with boron-doped diamond foils
Open Research DataThis dataset contains electrochemical examination of SPCE paste and SPCE containing boron-doped diamond BDD foils. The studies include kinetics analyses with cyclic voltammetry and electrochemical impedance spectroscopy with different redox probes: hexacyanoferrate(III) and Hexaammineruthenium(III) and potentiostatic open circuit potential at different...
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Oxygen partial pressure and temperature dependence of R-CPE1 resistance of symmetrical porous SrTi0.30Fe0.70O3 electrode on CGO substrate
Open Research DataThis dataset contains values of equivalent circuit element R-CPE1 resistance at different temperatures (800 °C, 700 °C, 600 °C and 500 °C) and oxygen partial pressures (100%, 80%, 50% 30%, 20%, 15%, 10%, 5%, 2.5%, 1%, and 0.3% pO2) of symmetrical SrTi0.30Fe0.70O3 electrode sintered at 800 °C. This values were obtained by fitting each measured impedance...
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Oxygen partial pressure and temperature dependence of R-CPE2 frequency of symmetrical porous SrTi0.30Fe0.70O3 electrode on CGO substrate
Open Research DataThis dataset contains values of equivalent circuit element R-CPE2 frequency at different temperatures (800 °C, 700 °C, 600 °C and 500 °C) and oxygen partial pressures (100%, 80%, 50% 30%, 20%, 15%, 10%, 5%, 2.5%, 1%, and 0.3% pO2) of symmetrical SrTi0.30Fe0.70O3 electrode sintered at 800 °C. This values were obtained by fitting each measured impedance...
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Oxygen partial pressure and temperature dependence of R-CPE1 capacity of symmetrical porous SrTi0.30Fe0.70O3 electrode on CGO substrate
Open Research DataThis dataset contains values of equivalent circuit element R-CPE1 capacity at different temperatures (800 °C, 700 °C, 600 °C and 500 °C) and oxygen partial pressures (100%, 80%, 50% 30%, 20%, 15%, 10%, 5%, 2.5%, 1%, and 0.3% pO2) of symmetrical SrTi0.30Fe0.70O3 electrode sintered at 800 °C. This values were obtained by fitting each measured impedance...
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Oxygen partial pressure and temperature dependence of R-CPE1 frequency of symmetrical porous SrTi0.30Fe0.70O3 electrode on CGO substrate
Open Research DataThis dataset contains values of equivalent circuit element R-CPE1 frequency at different temperatures (800 °C, 700 °C, 600 °C and 500 °C) and oxygen partial pressures (100%, 80%, 50% 30%, 20%, 15%, 10%, 5%, 2.5%, 1%, and 0.3% pO2) of symmetrical SrTi0.30Fe0.70O3 electrode sintered at 800 °C. This values were obtained by fitting each measured impedance...
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Oxygen partial pressure and temperature dependence of R-CPE2 resistance of symmetrical porous SrTi0.30Fe0.70O3 electrode on CGO substrate
Open Research DataThis dataset contains values of equivalent circuit element R-CPE2 resistance at different temperatures (800 °C, 700 °C, 600 °C and 500 °C) and oxygen partial pressures (100%, 80%, 50% 30%, 20%, 15%, 10%, 5%, 2.5%, 1%, and 0.3% pO2) of symmetrical SrTi0.30Fe0.70O3 electrode sintered at 800 °C. This values were obtained by fitting each measured impedance...
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Oxygen partial pressure and temperature dependence of R-CPE2 capacity of symmetrical porous SrTi0.30Fe0.70O3 electrode on CGO substrate
Open Research DataThis dataset contains values of equivalent circuit element R-CPE2 capacity at different temperatures (800 °C, 700 °C, 600 °C and 500 °C) and oxygen partial pressures (100%, 80%, 50% 30%, 20%, 15%, 10%, 5%, 2.5%, 1%, and 0.3% pO2) of symmetrical SrTi0.30Fe0.70O3 electrode sintered at 800 °C. This values were obtained by fitting each measured impedance...
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Assessment of protective properties of rubber lining in absorbers of flue gas desulphurization systems.
PublicationResults of research on degradation of rubber lining which is the main protection of absorbers in flue gas desulphurization (FGD) systems were presented. The power plant where the system operated is lignite-fired. Owing to measurements using electrochemical impedance spectroscopy and gravimetric determination of water content in the lining, the areas of the system which are most exposed to degradation were shown. The results obtained...
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Broadband Modeling of Motor Cable Impact on Common Mode Currents in VFD
PublicationExamination of conducted EMI generation and propagation in AC motor drives fed by frequency converter requires to consider parasitic capacitances in converters, motor windings and feeding cables to be taken into account. AC motor winding voltage transients and related common mode currents are significantly correlated with resonance effects occurring in converter's load circuits. Intensity levels of these phenomena depend...
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Motor Cable Influence on the Conducted EMI Emission of the Converter Fed AC Motor Drive. - Vol. 1
PublicationInvestigation of conducted electromagnetic interference in AC motor drives fed by pulse width modulated voltage converters requires considering parasitic capacitances in converters, motor windings and feeding cables to be taken into account. Motor voltage transients and related conducted electromagnetic emission are significantly correlated with resonance effects occurring in load circuits. The levels of intensity of these phenomena...
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Implementacja w środowisku LabVIEW aplikacji do badania wpływu dynamicznych zmian napięć zakłócających na dokładność metody podharmonicznej
PublicationWyznaczanie rezystancji lub impedancji uziemienia metodą podharmonicznej umożliwia uzyskanie dobrej dokładności pomiaru nawet w obecności silnych zakłóceń pochodzących od prądów błądzących występujących w gruncie. Metoda podharmonicznej wykazuje znaczną odporność na zakłócenia o częstotliwości sieciowej jak i stałoprądowe. Problem mogą stanowić natomiast zmiany dynamiczne sygnałów zakłócających spowodowane np. rozruchami urządzeń...
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WŁAŚCIWOŚCI ELEKTRYCZNE SZKIEŁ TLENKOWYCH ZAWIERAJĄCYCH Fe2O3
PublicationZbadano właściwości elektryczne szkieł krzemianowo – ołowiowo - żelazowych. Szkła tlenkowe zawierające jony żelaza mogą potencjalnie wykazywać przewodnictwo polaronowe. Celem niniejszej pracy było bliższe określenie zachodzącego w nich mechanizmu przewodnictwa. Wytworzono szkła o składzie dobranym na podstawie ich zakresu szklenia: (50 – 0.5x)[SiO2, PbO] - xFe2O3 gdzie x wynosił odpowiednio 2, 5, 10, 15, 20 i 25 (w % mol). Otrzymane...
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New method using bilinear transformation for parameter identification ofanticorossion coatings.
PublicationArtykuł przedstawia nową metodę diagnostyki powłok antykorozyjnych z wykorzystaniem przekształcenia biliniowego. Możliwa jest identyfikacja parametrów schematu zastępczego powłoki na podstawie pomiaru impedancji obiektu na kilku, optymalnie dobranych częstotliwościach pomiarowych. Podano zasady doboru optymalnych częstotliwości pomiarowych. Ich liczba jest równa liczbie elementów schematu zastępczego. Opracowany algorytm identyfikacji...
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Rigorous Modal Analysis of Structures Containing Inhomogeneous Dielectric Cylinders.
PublicationW pracy wykorzystano zmodyfikowaną procedurę iteracyjną i metodę dopasowania rodzajów w celu analizy struktur zawierających asymetrycznie umieszczone, niepełnej wysokości lub wielowarstwowe, niejednorodne, cylindryczne rezonatory dielektryczne. Analiza bazuje na nowatorskiej koncepcji zwanej hybrydową macierzą impedancyjną (HIM - hybryd impedancje matrix), która opisuje relacje pomiędzy całkowitym polem elektrycznym i magnetycznym...
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Morphological and electrochemical characterization of ceramic carbon foam electrodes water treatment applications
Open Research DataThis dataset contains morphological and electrochemical characterization of ceramic carbon foam employed as an electrode (CFFE) for the oxidation of a target pollutant. The dataset includes:
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Dynamiczne wyznaczanie parametrów elektrycznego obwodu szeregowego
PublicationPo załączeniu napięcia na skutek istnienia inercji prąd w obwodzie zaczyna narastać od wartości zerowej do znamionowej. W tym czasie narastają spadki napięć na rezystancjach (impedancjach obwodu) do chwili spełnienia prawa Kirchhoffa. Można utworzyć układ ze sprzężeniem zwrotnym (układ regulacji stałowartościowej bądź nadążnej), który poszukuje parametrów obwodu spełniających prawa Kirchhoffa – elementy nie muszą być liniowe. W...
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Determination of Mathematical Model Parameters of a Medium Frequency Transformer
PublicationThe paper presents the results of experimental studies of the medium frequency transformer. The object of the research was a prototype of a single-phase transformer with a core made of ferrite I-core elements and windings made of Litz conductors. The research was carried out to determine the parameters of the transformer's mathematical model. The scope of the tests included determining the magnetic hysteresis loop and measuring...
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Hybrid Technique for the EM Scattering Analysis with the Use of Ring Domain Decomposition
PublicationA hybrid technique combining finite-element and mode-matching methods for the analysis of scattering problems in open space is presented here. The main idea is based on impedance matrix descriptions of the boundary surrounding the discrete computational domain and combine it with external field described analytically. The discrete analysis, which is the most time- and memory-consuming, is limited here only to the close proximity...
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Insightful Analysis of Phenomena Arising at the Metal|Polymer Interphase of Au-Ti Based Non-Enzymatic Glucose Sensitive Electrodes Covered by Nafion
PublicationThis paper focuses on the examination of glucose oxidation processes at an electrode material composed of gold nanoparticles embedded in a titanium template. Three dierent conditions were investigated: the chloride content in the electrolyte, its ionic conductivity and the presence of a Nafion coating. The impact of the provided environment on the oxidation reaction was evaluated by cyclic voltammetry (CV) and electrochemical impedance...
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Novel Structure and EM-Driven Design of Small UWB Monopole Antenna
PublicationA novel structure of a small UWB monopole antenna is presented. In our approach, a compact size is achieved by means of a meander line for current path enlargement as well as the two parameterized slits that introduce additional degrees of freedom helping to ensure good impedance matching. The antenna design is carried out using surrogate-based optimization involving variable-fidelity EM simulations. This allows us to simultaneously...
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A Concept and Design Optimization of Compact Planar UWB Monopole Antenna
PublicationA novel structure concept of a compact UWB monopole antenna is introduced together with a low-cost design optimization procedure. Reduced footprint is achieved by introduction of a protruded ground plane for current path increase and a matching transformer to ensure wideband impedance matching. All geometrical parameters of the structure are optimized simultaneously by means of surrogate based optimization involving variable-fidelity...
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Improvement of electrochemical action of zinc-rich paints by addition of nanoparticulate zinc
PublicationThe influence of nanosized particles on electrochemical action of standard zinc-rich paints by means of SEM as well as potential and impedance measurements has been investigated. The motivation for doing this was to obtain additional electrical connection between the spherical microparticles themselves and zinc particles and steel substrate. Overall zinc content was at the level of 92% by weight. Samples with different concentration...
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Space-mapping-based design flow of miniaturized broadband matching transformer with perforated metallization
PublicationA fast design procedure of unconventional passive components has been presented and experimentally validated on the basis of a wideband microstrip four-section matching transformer (50:6 OHm). A classic impedance matching circuit has been miniaturized by means of compact microstrip resonant cells (CMRCs) leading to a considerable length reduction (34%) together with minor degradation in its performance. The spacemapping-based design...
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Electrical conductivity and relaxation processes in V2O5 nanorods prepared by sol–gel method
PublicationProperties of high purity V2O5 nanorods prepared by a sol – gel method are presented. The studied materials were characterized by: X-ray diffractometry (XRD), scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). The electrical impedance was measured as a function of temperature and frequency. The obtained results show that the electrical conductivity increases with increasing temperature. The d.c. conductivity...
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Exploring Mechanism of Corrosion Inhibition of WE43 and AZ31 Alloys by Aqueous Molybdate in Hank’s Solution by Multisine Impedimetric Monitoring
PublicationThe concept of utilizing multisine dynamic electrochemical impedance spectroscopy to monitor effectiveness of a model molybdate inhibitor for AZ31 and WE43 Mg alloys is proposed. The corrosion kinetics and instantaneous values of inhibition efficiency (IE) of molybdate at concentrations up to 150 mM were examined. The inhibitor provides inhibition in Hank’s solution at concentrations starting from ca. 25 mM, with the IE of about...
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Left-handed propagation characteristics of a dielectric and metal-loaded periodic circular waveguide
PublicationIn this paper, a periodic dielectric/metallic rod is located in a circular waveguide to obtain left-handed operation. Two geometries of the dielectric/metallic rod are proposed and examined. The dispersion characteristics of the investigated waveguides are obtained using a surface impedance model. Moreover, equivalent circuit models are proposed allowing for calculation of the dispersion characteristics and scattering parameters...
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A novel sensor for measuring temperature profile during the thermoablation
PublicationAbstract — A novel approach for monitoring a temperature distribution inside a tissue during thermoablation is presented in the paper. A thermal profile is measured using a set of serially connected thermistors each bypassed by a capacitor. This technique allows a two-wire and simultaneous multi- point measurements using a multi-frequency measurement of electrical impedance. It is...
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Electrochemical and photoelectrochemical properties of the interface between titania nanotubes covered by conducting polymer in aqueous by conducting polymer in aqueous electrolytes – The effect of various geometry and electrolytes concentration
PublicationIn the present work we show the impact of nanotubes (NTs) geometry of titania utilized as a substrate in organic-inorganic systems acting as a p-n junction on efficient conversion of radiation energy into electrochemical energy. The electrolytic bath composition and electrolysis conditions were controlled in order to obtain TiO2NTs of various geometry as a result of electrochemical oxidation of titanium foil. The electrode material...
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Development Of Dynamic Method For Evaluation Of Corrosion Rate On The Example Of Organic Corrosion İnhibitor
PublicationMeasurements of the corrosion rate belong to the most important aspects of materials science. In order to reduce material loss corrosion inhibitors are used. However selection of proper inhibitor should be based on evaluation of its mechanism and effective concentrations. Mechanism of inhibition usually has dynamic character so physicochemical parameters are changing in time. Most of actually used methods...