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Search results for: izolowany przeksztaltnik dc-dc, sic mosfet, transformator macierzowy, pokladowa ladowarka akumulatorow.
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Influence of circuit breaker operation upon transformeros residual flux and inrush current
PublicationPrzedstawiono model i wyniki obliczeń prądu i strumienia magnetycznego w układzie zawierającym transformator trójfazowy i wyłącznik. Opracowano obwodowy model łącznika z łukiem elektrycznym. Model łuku zbudowano w oparciu o jego statyczną charakterystykę prądowo-napięciową z uwzględnieniem uproszczonej charakterystyki dynamicznej. Przeprowadzone symulacje wykazały, że wartość maksymalna prądu włączania transformatora zależy zarówno...
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Compact microstrip to coplanar standard transformer.
PublicationW pracy zaprezentowano transformator standardu umożliwiający bezodbiciowe połączenie linii mikropaskowej z linią koplanarną. Konstrukcja układu opiera się na założeniu zachowania jednakowej wartości impedancji w każdym przekroju poprzecznym struktury. Zaprojektowano i przebadano dwa rozwiązania z ze skokową i ciągłą zmianą szerokości linii. Do badań numerycznych wykorzystano symulator pełnofalowy Momentum. W symulacjach uwzględniono...
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Advanced operating methods
PublicationSelected operating methods of resistive gas sensors were presented. The methods utilize flicker noise (1/f noise), which gives additional information about ambient gas when compared with the recorded changes of DC resistance only. Methods of flicker noise measurements were outlined. Recently developed prototype gas sensors comprising golden nanoparticle functionalized with organic ligands can generate intense flicker noise induced...
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Photovoltaic Maximum Power Point Technique based on Incremental Conductance (INCON) control algorithm
PublicationMaximum output power status can significantly improve the deployment rate of solar energy system. In order to get the maximum power output, issue of tracking maximum power point (MPP), reduced harmonics around MPP and improve efficiency of the solar power energy system, this paper presents the improved maximum power point tracking (MPPT) control...
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Optimizing conductivity in Na-V-Te-O glass through controlled heat treatment
PublicationSemiconducting Na2O-V2O5-TeO2 glasses with various Na2O contents were melted and subjected to controlled heating to improve conductivity. Topography analysis were performed using confocal microscopy and scanning electron microscopy on both as-quenched and heat-treated samples. X-ray diffraction confirmed the amorphous nature of the samples post-melting, with subsequent heating resulting in the formation of nanocrystallites primarily...
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Nanostructure and dielectric behavior of vanadate glasses containing BaTiO3
PublicationThe ac and dc electrical conductivity of barium titanate doped bismuth-vanadate as-quenched and heat-treated materials was measured in the frequency range from 1 mHz to 1 MHz and in the temperature range from 153 K to 423 K with the impedance spectroscopy method. The microstructure was investigated by means of XRD, scanning electron microscopy (SEM), atomic force microscopy (AFM) and confocal microscopy. The obtained results showed...
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Highly stable CsFAPbIBr perovskite solar cells with dominant bulk recombination at real operating temperatures
PublicationMixed-cation mixed-halide perovskite solar cells have been characterized in DC at different temperatures (from −20 °C up to 50 °C) and the time evolution of the device efficiency has been assessed using different degradation protocols (indoors and outdoors). The completely planar p–i–n structure is ITO/CuNiOx/PTAA/CsFAPbIBr/PCBM/PEI/Ag. Pristine current–voltage characteristics barely show hysteresis, at any temperature. Open circuit...
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Low-frequency noise in Au-decorated graphene–Si Schottky barrier diode at selected ambient gases
PublicationWe report results of the current–voltage characteristics and low-frequency noise in Au nanoparticle (AuNP)-decorated graphene–Si Schottky barrier diodes. Measurements were conducted in ambient air with addition of either of two organic vapors, tetrahydrofuran [(CH2)4O; THF] and chloroform (CHCl3), as also during yellow light illumination (592nm), close to the measured particle plasmon polariton frequency of the Au nanoparticle...
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Superconductivity in CaBi2
PublicationSuperconductivity is observed with critical temperature Tc = 2.0 K in self-flux-grown single crystals of CaBi2. This material adopts the ZrSi2 structure type with lattice parameters a = 4.696(1) Å, b = 17.081(2) Å and c = 4.611(1) Å. The crystals of CaBi2 were studied by means of magnetic susceptibility, specific heat and electrical resistivity measurements. The heat capacity jump at Tc is DC/gTc = 1.41, confirming bulk superconductivity;...
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Electrical properties of Na2O-CaO-P2O5 glasses doped with SiO2 and Si3N4
PublicationSodium-calcium-phosphate glasses doped with SiO2 or Si3N4 having similar sodium ion concentrations were prepared by melt quenching. The conductivity was measured by impedance spectroscopy under nitrogen atmosphere in a wide frequency range (10 mHz–1 MHz) and wide temperature range (153–473 K). At 36.6 °C, DC conductivities of all glasses vary between 1.1 ∗ 10−12 and 8.9 ∗ 10−12 S cm−1 and have similar activation energies (between...
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Portable exhaled breath analyzer employing fluctuation-enhanced gas sensing method in resistive gas sensors
PublicationThis paper presents a portable exhaled breath analyser, developed to detect selected diseases. The set-up employs resistive gas sensors: commercial MEMS sensors and prototype gas sensors made of WO3 gas sensing layers doped with various metal ingredients. The set-up can modulate the gas sensors by applying UV light to induce physical changes of the gas sensing layers. The sensors are placed in a tiny gas chamber of a volume...
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Ionic conductivity behavior by activated hopping conductivity (AHC) of barium aluminoborosilicate glass–ceramic system designed for SOFC sealing
PublicationNon-conducting BaO-B2O3-Al2O3-SiO2 parent glasses designed for solid oxide fuel cell (SOFC) sealing applications were prepared using the melt-quenching technique. The glass formation region was determined according to phase equilibrium relations and was found to be in the composition range 70BaO-(x)Al2O3-(10−x)B2O3-20SiO2 where 3.0 < x < 6.0 wt%. The conductivity values obtained conductivity ranged from 10−5 to 10−10 S/cm at temperatures...
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Falowniki napięcia z quasi-rezonansowym obwodem pośredniczącym w układach napędowych
PublicationW monografii przedstawiono zagadnienia związane z wykorzystaniem pośrednich przemienników częstotliwości z rezonansowymi oraz quasi-rezonansowymi obwodami pośredniczącymi w układach napędowych. Omówiono wpływ przełączania „twardego” przy niezerowych prądach i napięciach łączników na właściwości eksploatacyjne elektrycznego układu napędowego. Ponadto dokonano przeglądu wybranych topologii przekształtników DC/AC, zapewniających techniki...
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The power spectral density of audible noise and electric disturbances in ship’s electrical drive systems with frequency converters
Open Research DataThe presented dataset is part of research focusing on the impact of the ship's electrical drive systems with frequency converters on vibrations and the level of audible noise on ships.
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Plasmon resonance in a TiO2-Au NPs structures
Open Research DataInvestigated structures were deposited on a pre cleaned Corning 1737 glass substrates, which provided flat optical transmission characteristics and high transmission coefficient in a visible light range. Plasmonic nanostructures were formed as a result of thermal annealing. For gold films with thickness of 2.8 nm depiction a table-top dc magnetron sputtering...
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Measurements of power supply system properties of "Magnetic SpeedLine" ultra-fast robot prototype for IML labeling
Open Research DataTests of the power supply system of "SpeedLine magnetic" ultra-fast industrial robot for IML labeling were carried out to analyze the effect of the active power filter (APF) parameters on the power quality. at the target duty cycle. Tests were performed with the target duty cycle. Linear synchronous motors with permanent magnets were used to drive...
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Assessment of organic coating degradation via local impedance imaging
PublicationThe paper presents a new approach to organic coating condition evaluation at micrometer scale using localized impedance measurements. It is based on atomic force microscopy (AFM) in contact mode. Impedance is measured between conductive AFM tip and metal substrate covered with organic coating. A single-frequency voltage perturbation signal is applied between the electrodes and current response signal is registered. As the tip is...
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Edge-Guided Mode Performance and Applications in Nonreciprocal Millimeter-Wave Gyroelectric Components
PublicationThe analogies between the behavior of gyromagnetic and gyroelectric nonreciprocal structures, the use of the simple transfer matrix approach, and the edge-guided (EG) wave property, supported in a parallel plate model for integrated magnetized semiconductor waveguide, are investigated in those frequency regions, where the effective permittivity is negative or positive. As with their ferrite counterparts, the leakage of the EG waves...
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Low cost set-up for supercapacitors parameters evaluation
PublicationSupercapacitors are capable to store relatively high amount of energy comparing to its mass. Growing number of these devices applications requires development of new testing methods. Standard methods of evaluation of supercapacitor parameters, as cycling voltammetry, CV, galvanostatic cycling with potential limitation, GCPL, impedance measurements, require equipment of high cost...
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Przeprowadzenie prób obejmujących miernictwo i charakteryzację opracowanych elementów, przyrządów i prototypowych podukładów funkcjonalnych zgodnie z obowiązującymi normami - zadanie 4. projektu ''Nowe technologie na bazie węglika krzemu i ich zastosowania w elektronice wielkich częstotliwości, dużych mocy i wysokich temperatur''
PublicationPrzedstawionmo główne cele zadania 4. projektu zamawianego nt. ''Nowe technologie na bazie węglika krzemu i ich zastosowania w elektronice wielkich częstotliwości dużych mocy i wysokich temperatur. Są to: analiza właściwości produkowanych obecnie komercyjnych elementów i przyrządów półprzewodnikowych z SiC oraz przygotowanie stanowisk laboratoryjnych do pomiarów parametrów i chrakterystyk tych przyrządów.Przewidywane jest opracowanie...
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New insights into structural, optical, electrical and thermoelectric behavior of Na0.5Bi0.5TiO3 single crystals
PublicationThe single crystals of lead-free Na0.5Bi0.5TiO3 were grown using the Czochralski method. The energy gaps determined from X-ray photoelectron spectroscopy (XPS) and optical measurements were approximately 2.92 eV. The current-voltage characteristics, depolarization current, dc (σdc) and ac (σac) electrical conductivity, and Seebeck coefficient of the crystals were investigated. The frequency/temperature-dependent electrical properties...
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Enhancing electrical properties through in-situ controlled nanocrystallization of V2O5–TeO2 glass
PublicationV2O5–TeO2 glass–ceramics (VTGC) were prepared by controlled annealing of the V2O5–TeO2 glass (VTG), which illustrates a parent glass matrix with a single charge carrier. The annealing proceeded at six temperatures selected between the glass transition and the maximum of the frst crystallization process to obtain various nanocrystallite sizes. Heat treatment caused an increase in DC conductivity by 2.5–3.5 (250–285 °C) order of...
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Structural and electrical transport properties of Pr-doped SrTi0.93Co0.07O3-δ a novel SOEC fuel electrode materials
PublicationSolid Oxide Electrolyzer Cells (SOECs) are very promising electrochemical devices for the production of syngas (H2/CO) by H2O and CO2 co-electrolysis. The structure, microstructure and electrical properties of the fuel electrode material play a crucial role in the performance of the whole cell and efficiency of electrocatalytic reduction of steam into hydrogen. In the present work, a novel Co and Pr co-doped SrTiO3-δ material attracted...
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Development and test of fex, a fingers extending exoskeleton for rehabilitation and regaining mobility
PublicationThis paper presents the design process of an exoskeleton for executing human fingers' extension movement for the rehabilitation procedures and as an active orthosis purposes, together with its first clinical usability tests of a robotic exoskeleton. Furthermore, the Fingers Extending eXoskeleton (FEX) is a serial, under-actuated mechanism capable of executing fingers' extension. FEX is based on the state-of-art FingerSpine serial...
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Diamond surface modification following thermal etching of Si supported hydrogenated diamond films by DBr
PublicationZbadano, wykorzystując spektroskopię oscylacyjną (HREELS - High Resolution Electron Energy Loss Spectroscopy) modyfikacje chemiczne powierzchni wodorowanego diamentu, umieszczonego na podkładzie krzemowym i wystawionego na działanie DBr a następnie podgrzanego do temp. powyżej 600 st.K. Przedstawiona procedura powoduje tworzenie się węglika krzemu SiC na powierzchni warstwy diamentowej, co jest widoczne na widmie HREEL jako dwa...
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Measurements of drive system properties of the "Magnetic SpeedLine" ultra-fast robot prototype for IML labeling
Open Research DataTests of the drive system of the ultra-fast robot "SpeedLine magnetic" for labeling with the IML method were carried out in order to analyze the influence of the operating parameters of the drive system on the correctness and quality of the drive system.
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Power Hardware-In-the-Loop Approach for Autonomous Power Generation System Analysis
PublicationThe article presents the Power Hardware-In-the-Loop (PHIL) dynamic model of a synchronous generator of 125 kVA for autonomous power generation system analysis. This type of system is typically composed of electrical energy sources in the form of several diesel generator units with synchronous machines, the main distribution switchboard and different loads. In modern power distribution systems, the proposed power management strategies...
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Correlations of structural, thermal and electrical properties of sodium doped complex borophosphosilicate glass
PublicationBorophosphosilicate glasses with varying sodium ion concentrations were investigated for their, structural, thermal, and electrical properties. All the obtained glasses were transparent except the glass with the highest sodium content, which exhibited translucency due to inhomogeneities. Increasing sodium content led to reduced boron and silicon content while maintaining a constant B/Si ratio, indicating progressive depolymerization...
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Viscous versus electromagnetic damping – amplification in a neighbourhood of a mechanism singular position
PublicationIn the paper, damping of vibrations are considered and compared in a mechanical and in a electromechanical system. In the system, a continuous beam is considered as the main vibrating element. The compared dissipations methods are based on: viscous dampers and DC generators. To increase the possible damping effectiveness, velocity amplification is proposed, i.e., a mechanism is introduced between the beam and the damping element....
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Nonlinear modeling of traction transformer with coiled iron core for dynamic simulation
PublicationW referacie przedstawiono wyprowadzenie zastępczego modelu obwodowego transformatora trakcyjnego o rdzeniu zwijanym do analiz zachowania sie transformatora w układzie napedowym jednostki trakcyjnej. Model zakłada nieliniowa charakterystyke magnesowania B-H i anizotropowe właściwosci magnetyczne i elektryczne zwijanego rdzenia. Wyprowadzenie modelu oparto na metodzie energetycznej Lagrange'a. Uzwojenia zostały zamodelowanie jako...
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Analog multiplier for a low-power integrated image sensor
PublicationArtykuł przedstawia nowe podejście do projektowania tanich niskomocowych zintegrowanych sensorów optycznych. W odróżnieniu od wcześniej stosowanych rozwiązań opartych na masowym przetwarzaniu równoległym, zaproponowany mnożnik macierzowy charakteryzuje się korzystniejszymi cechami. Proponowane rozwiązanie, chociaż mniej elastyczne w sensie liczby możliwych do zaimplementowania algorytmów wstępnej obróbki obrazu, cechuje się znaczącą...
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Analog multiplier for a low-power integrated image sensor
PublicationArtykuł przedstawia nowe podejście do projektowania tanich niskomocowych zintegrowanych sensorów optycznych. W odróżnieniu od wcześniej stosowanych rozwiązań opartych na masowym przetwarzaniu równoległym, zaproponowany mnożnik macierzowy charakteryzuje się korzystniejszymi cechami. Proponowane rozwiązanie, chociaż mniej elastyczne w sensie liczby możliwych do zaimplementowania algorytmów wstępnej obróbki obrazu, cechuje się znaczącą...
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Matematyczne Modele Ekonomii
e-Learning CoursesPojęcie modelu ekonometrycznego - modele jednorównaniowe i wielorównaniowe. Rodzaje zmiennych. Estymacja modeli prostych i rekurencyjnych. Metoda zmiennych instrumentalnych (MZI). Model o równaniach współzależnych (MRW). Postać pierwotna i zredukowana MRW. Identyfikacja modeli MRW. Szacowanie formy zredukowanej MRW. Pośrednia MNK. Estymator 2MNK. Dynamiczne modele wielorównaniowe- zapis macierzowy. Teoria ekonomiczna. Dane statystyczne....
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Analogowe filtry OTA-C czasu ciągłego - wybrane zagadnienia analizy i syntezy
PublicationW rozdziale przedstawiono istotne problemy dotyczące metod analizy, syntezy i projektowania analogowych filtrów OTA-C czasu ciągłego. Zaprezentowano analityczny model ogólnej struktury dla tej klasy filtrów. Podano zunifikowany macierzowy opis dla konfiguracji układowych filtrów OTA-C trybu napięciowego oraz prądowego. Omówiono podstawy analizy wrażliwości ogólnej struktury oraz przedstawiono reprezentatywne przykłady syntezy i...
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Characterization methods of nickel nano-particles obtained by the ex-solution process on the surface of Pr, Ni-doped SrTiO3 perovskite ceramics
PublicationIn this paper, a novel electrode material based on Pr, Ni co-doped strontium titanate ( Sr0.7Pr0.3)xTi1−yNiyO3 with constant amount of 30% praseodymium dopant, different amount of nickel (y = 0.06 and y = 0.10) and additional nonstoichiometry in Sr-site (x = 1; x = 0.9 and x = 0.8) was investigated as fuel electrode for SOEC devices. A porous ceramics were prepared by solid-state reaction method. X-ray diffraction measurements...
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Assessment of Electronic Sensing Techniques for the Rapid Identification of Alveolar Echinococcosis through Exhaled Breath Analysis
PublicationHere we present a proof-of-concept study showing the potential of a chemical gas sensors system to identify the patients with alveolar echinococcosis disease through exhaled breath analysis. The sensors system employed comprised an array of three commercial gas sensors and a custom gas sensor based on WO3 nanowires doped with gold nanoparticles, optimized for the measurement of common breath volatile organic compounds. The measurement...
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Reconstruction of 3D image of corona discharge streamer
PublicationIn this paper, the method of reconstruction of the 3D structure of streamers in DC positive corona discharge in nozzle-to-plate electrode configuration is presented. For reconstructing of 3D image of corona discharge streamer we propose a stereographical method, where streamers are observed from several directions simultaneously. The multi-directional observation enabled to obtain fine positional coordinates of streamers for a...
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Investigation of structural, thermal, and electrical properties of sodium-doped oxynitride glass-ceramics
PublicationThis study aimed to investigate the influence of Na2O addition on the structural, thermal, and electrical characteristics of oxynitride glass-ceramics within the Na–K–Mg–Ca–Al–Si–O–N system. Oxynitride glass-ceramic samples were prepared via spark plasma sintering (SPS) with sodium oxide doping levels ranging from 0 wt% to 12 wt%. FESEM analysis revealed changes in sample morphology with increasing sodium content, indicating the...
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Electrical properties and structure of lead-borate glass containing iron ions.
PublicationThe ac and dc conductivity in iron–lead-borate glass samples was investigated in the frequency range from 1 mHz to 1 MHz and in the temperature range from 153 K to 423 K. The structure was investigated by the means of atomic force microscopy (AFM) and the crystalline phases (if present) were identified by the means of X-ray diffractometry. Two types of ac electrical behaviour were observed. The first group of glass samples which...
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Sensorless Control of Induction Motor Based on Super-Twisting Sliding Mode Observer With Speed Convergence Improvement
PublicationThe super twisting sliding-mode observer (ST-SMO) has been proposed to achieve an effective method for alleviating low-order harmonics of measured quantities, issues related to DC drift, and suppression of chattering due to low-frequency sampling. The conventional ST-SMO, on the other hand, suffers from control delay in the convergence trajectory due to the system disturbance, resulting in decreased anti-disturbance capability...
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Low Frequency Conducted Emissions of Grid Connected Static Converters
PublicationPulse-width modulated rectifiers are nowadays commonly used for AC to DC power conversion. PWM rectification technology is very effective and allows for bidirectional power flow with the possibility of power factor improvement and low-order harmonic emission limitation. Unfortunately, employed PWM boost topology results with generation of input current harmonic distortions in a frequency range tightly correlated to modulation frequency....
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High Frequency Harmonics Emission in Smart Grids
PublicationPulse-width modulated rectifiers are nowadays commonly used for AC to DC power conversion. PWM rectification technology is very effective and allows for bidirectional power flow with the possibility of power factor improvement and low-order harmonic emission limitation. Unfortunately, employed PWM boost topology results with generation of input current harmonic distortions in a frequency range tightly correlated to modulation frequency....
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Investigations on the immunosuppressive activity of derivatives of mycophenolic acid in immature dendritic cell
PublicationThe main activity of mycophenolic acid (MPA) and its analogs is the inhibition of proliferation of T cells. Here, we hypothesized that MPA and its conjugates inhibits also the activity of antigen-presenting cells (APC) including dendritic cells (DCs). We tested the effect of novel amino acid derivatives of MPA and conjugates of MPA with acridines/acridones on DCs by flow cytometry, ELISA and MLR assay. Both acridines/acridone derivatives...
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Status report on high temperature fuel cells in Poland – Recent advances and achievements
PublicationThe paper presents recent advances in Poland in the field of high temperature fuel cells. The achievements in the materials development, manufacturing of advanced cells, new fabrication techniques, modified electrodes and electrolytes and applications are presented. The work of the Polish teams active in the field of solid oxide fuel cells (SOFC) and molten carbonate fuel cell (MCFC) is presented and discussed. The review is oriented...
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Pomiary szumów m.cz. tranzystorów MESFET z węglika krzemu
PublicationTranzystory MESFET z węglika krzemu typu CRF24010 (CRREE) są przyrządami mocy przeznaczonymi do pracy w zakresie wysokich częstotliwości. Ze względu na możliwość oceny technologii tych przyrządów, a także ich jakości celowe jest określenie ich właściwości szumowych w zakresie małych częstotliwości. Przedstawiono wyniki badań wykonanych w celu oceny właściowści szumowych tranzystorów MESFET z SiC oraz zaproponowano schemat szumowy...
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Problemy pomiarów szumów diod z węglika krzemu
PublicationPrzedstawiono system do pomiaru szumów m.cz. diod Schottky'ego wykonanych z węglika krzemu (SiC) spolaryzowanych w kierunku przewodzenia i zaporowym, z uwzględnieniem specyfiki pomiaru szumów wybuchowych (RTS). Badane diody charakteryzują się wysokim prądem przewodzenia (do 12A) i wysokim napięciem zaporowym (typowo 600V i 1200V). Omówiono zagadnienia związane ze sposobami polaryzacji badanych diod i ich wpływ na wyniki pomiarów....
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Budowa i badania prototypowych podukładów funkcjonanych elektronicznych i energoelektronicznych, w tym wysokotemperaturowych, wykorzystujących opracowane elementy i przyrządy - zadanie 3. projektu ''Nowe technologie na bazie węglika krzemu i ich zastosowania w elektronice wielkich częstotliwości, dużych mocy i wysokich temperatur''
PublicationPrzedstawiono główne cele zadania 3. projektu zamawianego nt. ''Nowe technologie na bazie węglika krzemu i ich zastosowania w elektronice wielkich częstotliwości dużych mocy i wysokich temperatur''. Są to: badania typowych układów elektronicznych i energoelektronicznych z zastosowaniem kompercyjnych elementów i przyrządów z SiC w celu opracowania rozwiązań, które będą mogły być stosowane w praktyce i będą korzystniejsze niż zastosowane...
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Comparative analysis of switched reluctance motor control algorithms
PublicationПредмет исследования. Развитие микропроцессорной техники и силовой электроники позволило создавать недорогие и эффективные системы управления различными электромеханическими объектами, которые ранее широко не использовались из-за сложности управления. К таким устройствам можно отнести вентильно-индукторные электрические машины. Данные машины широко применяются в различных практических разработках, например, в тяговом электроприводе,...
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WIELOLEKOOPORNE ZAKAŻENIA CANDIDA - PROBLEM XXI WIEKU!
PublicationW ostatnich latach obserwuje się dramatyczny wzrost zakażeń grzybiczych, których przyczyną są grzyby z rodzaju Candida (C). Większość zakażeń wywoływana jest przez C. albicans, C. glabrata, C. krusei, C. parapsilosis i C. tropicalis. Dotychczas najczęściej stosowanymi lekami przeciwko Candida spp były azole, jednakże ze względu na występowanie naturalnej oporności na te antybiotyki (C. glabrata i C. krusei) coraz częściej azole...
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Analysis of energy efficiency of suburban railway transport network
PublicationRising numbers of agglomeration residents cause increased need for people movement on daily basis. Because of congestion of local roads, air pollution and limited parking space, providing mass transit based on electric traction is reasonable. While the electric rail vehicles are considered highly efficient in themselves, they need to be analyzed as a part of a transport network, because energy consumption depends on operating conditions...