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Analysis of electromagnetic disturbances in DC network of grid connected building-integrated photovoltaic system
PublikacjaThis paper focuses on conducted electromagnetic interference (EMI) emissions and propagation in the DC network of grid connected building integrated photovoltaic (PV) system. The investigated PV system, consists of ten solar panels, cabling and the grid-connected one phase inverter. The EMI simulation model of the real PV system has been developed with the aid of impedance analyzer measurements of solar panels and the DC network...
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Periodic and chaotic dynamics in a map‐based neuron model
PublikacjaMap-based neuron models are an important tool in modeling neural dynamics and sometimes can be considered as an alternative to usually computationally costlier models based on continuous or hybrid dynamical systems. However, due to their discrete nature, rigorous mathematical analysis might be challenging. We study a discrete model of neuronal dynamics introduced by Chialvo in 1995. In particular, we show that its reduced one-dimensional...
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Recent advances in electrochemically surface treated titanium and its alloys for biomedical applications: A review of anodic and plasma electrolytic oxidation methods
PublikacjaNowadays, titanium and its alloys are widely used materials in implantology. Nevertheless, the greatest challenge is still its appropriate surface treatment in order to induce optimal properties, which facilitates formation of a permanent bond between the implant and human tissue. The use of electrochemical treatment such as anodic oxidation or plasma electrolytic oxidation allows for the production of porous coating that mimics...
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Implementation of an Adaptive Method for Changing the Frequency Division of the Counter Clock Signal in a Frequency-to-Code Converter
PublikacjaProcessing physical quantities into an indirect signal is a standard method of transferring information about the measured quantity to the master system, which analyzes the data obtained from the acquisition system. The intermediate signal is very often the voltage, but another transmission medium can be the frequency of the output signal of the “physical quantity-to-frequency” converter. The article presents the implementation...
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Electrophoretic Deposition and Characteristics of Chitosan–Nanosilver Composite Coatings on a Nanotubular TiO2 Layer
PublikacjaThe 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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Effectiveness of various types of coating materials applied in reinforced concrete exposed to freeze–thaw cycles and chlorides
PublikacjaThis study assesses the durability of coated and uncoated concrete surfaces protected with four different coating materials: water-soluble (BW), solvent-based (BR), mineral (MI), and epoxy (EP). The durability assessment includes evaluating the absorption rate of water, pull-off adhesion strength, and coating material thickness. Concrete samples were subjected to immersion in regular water and a 7% urea solution, followed by...
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Electrocatalytic gas sensor with reference layer
PublikacjaIn 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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Dissociative ionization dynamics of dielectric gas C3F7CN
PublikacjaFluoronitrile C3F7CN is a promising candidate for the replacement of SF6 dielectric gas in high-voltage insulation. We present a combined experimental and theoretical study on its ionization dynamics probed in the 0-100 eV energy range. We exploited the total ion collection technique to determine the absolute ionization cross section, mass spectrometry to determine the fragment branching ratios and ab initio nonadiabatic molecular...
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Comparison of Impedance-Source Networks for Two and Multilevel Buck–Boost Inverter Applications
Publikacjampedance-source networks are an increasingly popular solution in power converter applications, especially in single-stage buck-boost power conversion to avoid additional front-end dc-dc power converters. In the survey papers published, no analytical comparisons of different topologies have been described, which makes it difficult to choose the best option. Thus, the aim of this paper is to present a comprehensive analytical comparison...
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Electrohydrodynamic Secondary Flow and Particle Collection Efficiency in a One-sided Spike-plate Type Electrostatic Precipitator
PublikacjaIn this work, results of electrohydrodynamic secondary flow and particle collection efficiency measurements in an electrostatic precipitator under positive and negative voltage polarity are presented. The electrostatic precipitator had two plate collecting electrodes and a single spike discharge electrode. The spike tips were only on one side of the discharge electrode, therefore called a one-sided spike electrode. The electrohydrodynamic...
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Time-domain measurement methods for R, L and C sensors based on aversatile direct sensor-to-microcontroller interface circuit
PublikacjatIn the paper new time-domain measurement methods for determining values of resistive (R), inductive(L) and capacitive (C) sensors based on a versatile direct sensor-to-microcontroller interface for microcon-trollers with internal analog-to-digital converters (ADCs) and analog comparators (ACs) are presented.The interface circuit consists of a reference resistor Rrworking as a voltage divider, a given R, L or C sensorand a microcontroller...
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Diffusible Hydrogen Control in Flux Cored Arc Welding Process
PublikacjaOne of the types of hydrogen degradation of steel welded joints is cold cracking. The direct cause of the formation of cold cracks is simultaneous presence of hydrogen, residual stresses and brittle structure. The way of preventing the occurring of degradation is to eliminate at least one of these factors. Practice has shown that the best solution is to control the amount of hydrogen in deposited metal. In this paper an experimental...
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Determination of toxic gases based on the responses of a single electrocatalytic sensor and pattern recognition techniques
PublikacjaA response from an electrocatalytic gas sensor contains fingerprint information about the type of gas and its concentration. As a result, a single gas sensor can be used for the determination of different gases. However, information about the type of gas and its concentration is hidden in the unique shape of the current–voltage response and it is quite difficult to explore. One of the ways to get precise information about the measured...
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Electric transport in organic system with planar DBP/F16ZnPc junction on the basis of direct current and small signal admittance spectra analysis
PublikacjaThe objective of this work was to determine electric transport in the organic device based on a planar junction of electron donor and electron acceptor materials, namely ITO/MoO3/DBP/F16ZnPc/BCP/Ag. The analysis reported herein was based on direct current-voltage measurements and small-signal admittance spectra in the dark and under illumination. Such analysis may provide information on potential barriers, parasitic resistances...
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Non-Contact Monitoring of ECG in the Home Environment—Selecting Optimal Electrode Configuration
PublikacjaCapacitive electrocardiography (cECG) is most often used in wearable or embedded measurement systems. The latter is considered in the paper. An optimal electrocardiographic lead, as an individual feature, was determined based on model studies. It was defined as the possibly highest value of the R-wave amplitude measured on the back of the examined person. The lead configuration was also analyzed in terms of minimizing its susceptibility...
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The concept of a new two-stage fuse for high power pulse forming
PublikacjaThis manuscript introduces the concept, physical operating principle and studies on a new and unique two stage forming fuse (TSFF) with interstage spark gap commutation and presents its application for forming high power pulses of extreme parameters. The paper classifies TSFF performance and compares it with conventional single-stage forming fuses. The conclusions are supported by analytical and experimental studies in laboratory...
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Effectiveness of various types of coating materials applied in reinforced concrete exposed to freeze–thaw cycles and chlorides
PublikacjaThis study assesses the durability of coated and uncoated concrete surfaces protected with four Different coating materials: water-soluble (BW), solvent-based (BR), mineral (MI), and epoxy (EP). The durability assessment includes evaluating the absorption rate of water, pull-of adhesion strength, and coating material thickness. Concrete samples were subjected to immersion in regular water and a 7% urea solution, followed by cyclic...
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Electrohydrodynamic Flow Patterns in a Narrow Electrostatic Precipitator with Longitudinal Wire Electrode for Various Electrode Geometries
PublikacjaRecently narrow electrostatic precipitators (ESPs) have become a subject of interest because of their possible application in diesel engines. In this paper results of 2-dimensional (2D) Particle Image Velocimetry (PIV) measurements of the flow patterns in a narrow ESP for a various electrode geometries are presented. The PIV measurements were carried out in the observation plane that is perpendicular to the ESP duct. The ESP was...
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SrCe0.9In0.1O3-δ-based reversible symmetrical Protonic Ceramic Cell
PublikacjaIn-doped SrCe0.9In0.1O3-δ (SCI) perovskite-type oxide is utilized as the solid electrolyte, as well as a component, together with SrFe0.75Mo0.25O3-δ (SFM) compound, in the composite-type electrodes to construct symmetrical Protonic Ceramic Fuel Cells (PCFC). With good mutual stability of SCI and SFM at high temperatures in water vapor-containing reducing and oxidizing conditions, as well as sufficient ionic conductivity with high...
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The Possibility of Phase Change Materials (PCM) Usage to Increase Efficiency of the Photovoltaic Modules
PublikacjaSolar energy is widely available, free and inexhaustible. Furthermore this source of energy is the most friendly to the environment. For direct conversion of solar energy into useful forms like of electricity and thermal energy, respectively photovoltaic cells and solar collectors are being used. Forecast indicate that the first one solution will soon have a significant part in meeting the global energy demand. Therefore it is...
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The influence of nanostructures size on V2O5 electrochemical properties as cathode materials for lithium ion battery
PublikacjaIn this paper, V2O5 nanostructures with a size depending on the annealing temperature are successfully synthesized by a sol-gel method. The crystal structure and morphology of samples are characterized by X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), transmission electron microscopy (TEM), selected area electron diffraction (SEAD) and scanning electron microscopy (SEM), respectively. Electrochemical testing such...
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Non-Gaussian Resistance Fluctuations in Gold-Nanoparticle-Based Gas Sensors: An Appraisal of Different Evaluation Techniques
PublikacjaVolatile organic compounds, such as formaldehyde, can be used as biomarkers in human exhaled breath in order to non-invasively detect various diseases, and the same compounds are of much interest also in the context of environmental monitoring and protection. Here, we report on a recently-developed gas sensor, based on surface-functionalized gold nanoparticles, which is able to generate voltage noise with a distinctly non-Gaussian...
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THE PROPERTIES OF NANOSILVER – DOPED NANOHYDROXYAPATITE COATING ON THE Ti13Zr13Nb ALLOY
PublikacjaThe aim of this research was to study the properties of nanohydroxyapatite (nanoHAp) and nanohydroxyapatite, doped with nanosilver (nanoHAp/nanoAg), coatings obtained by an electrophoretic deposition process. The suspensions was prepared by dispersing 0.1 g of HAp nanopowder for nanoHAp coatings and 0.1 g of nanoHAp and 0.025 g nanoAg for nanoHAp/nanoAg coatings. The deposition was carried out for 1 min at 50 V voltage followed...
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Nanotubular Oxide Layer Formed on Helix Surfaces of Dental Screw Implants
PublikacjaSurface 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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Innovative Bidirectional Isolated High-Power Density On-Board Charge for Vehicle-to-Grid
PublikacjaThis paper deals with developing and implementing a bidirectional galvanically isolated on-board charger of a high-power density. The power density of the new charger was 4 kW/kg and 2.46 kW/dm3, and the maximum efficiency was 96.4% at 3.4 kW. Due to the requirement to achieve a high-power density, a single-stage inverter topology was used. Regarding switching losses, due to the topology of the circuit with so-called hard switching,...
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Evaluation of VSC Impact on Power System Using Adequate P-Q Capability Curve
PublikacjaRenewable energy sources, which are becoming increasingly popular, often use a voltage source converter (VSC) for connection to the power system. Assessing the effects of connecting such a source to the power system is essential to ensure the proper operation of the power system and the connected source. For this purpose, it is necessary to know the range of active and reactive power generation by the converter. The authors indicate...
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Theoretical designing of selenium heterocyclic non-fullerene acceptors with enhanced power conversion efficiency for organic solar cells: a DFT/TD-DFT-based prediction and understanding
PublikacjaIn this study, we have designed and explored a new series of non-fullerene acceptors for possible applications in organic solar cells. We have designed four molecules named as APH1 to APH4 after end-capped modification of recently synthesized Y6-Se-4Cl molecule. Density functional theory and time dependent-density functional theory have been employed for computing geometric and photovoltaic parameters of the designed molecules....
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In Vitro Biological Characterization of Silver-Doped Anodic Oxide Coating on Titanium
PublikacjaDespite the high biocompatibility and clinical effectiveness of Ti-based implants, surface functionalization (with complex osteointegrative/antibacterial strategies) is still required. To enhance the dental implant surface and to provide additional osteoinductive and antibacterial properties, plasma electrolytic oxidation of a pure Ti was performed using a nitrilotriacetic acid (NTA)-based Ag nanoparticles (AgNP)-loaded calcium–phosphate...
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Comparative Analysis of Reactive Power Compensation Devices in a Real Electric Substation
PublikacjaA constant worldwide growing load stress over a power system compelled the practice of a reactive power injection to ensure an efficient power network. For this purpose, multiple technologies exist in the knowledge market out of which this paper emphasizes the usage of the flexible alternating current transmission system (FACTS) and presents a comparative study of the static var compensator (SVC) with the static synchronous compensator...
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Assessment of organic coating degradation via local impedance imaging
PublikacjaThe 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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Role of surface recombination in perovskite solar cells at the interface of HTL/CH3NH3PbI3
PublikacjaIn 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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Infrared techniques for natural convection investigations in channels between two vertical, parallel, isothermal and symmetrically heated plates
PublikacjaThe effect of the gap width between two symmetrically heated vertical, parallel, isothermal plates on intensity of natural convective heat transfer in a gas (Pr = 0.71) was experimentally studied using the balance and gradient methods. In the former method heat fluxes were determined based on measurements of the voltage and electric current supplying the heaters placed inside the walls. In the latter, heat fluxes were calculated...
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Problems of varistor quality assessment during exploitation
PublikacjaVaristors are commonly used elements which protect power supply networks against high-voltage surges or lightning. Therefore, quality and endurance of these elements is important to avoid losses when an expensive laboratory equipment would not be protected from random overvoltages. Additionally, excessive leakage currents generate serious costs due to high energy consumption. The paper presents shortly properties of varistors that...
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Methods of trend removal in electrochemical noise data – overview
PublikacjaIn this paper we shall review popular methods of trend removal from electrochemical noise time records. The basic principles of operation of the six most popular methods are explained. The proposed methods are: high - pass filtering, Moving Average Removal, polynomial detrending, wavelet detrending, Empirical Mode Decomposition and Variational Mode Decomposition. Estimation of trend removal quality...
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Switched-capacitor DC-DC converters in arbitrary switching mode - topologically derived resistive models based on incremental graph approach.
PublikacjaIn the preceding paper we reviewed some of modeling approaches aimed at systematic formulation and solution of switched capacitor DC-DC converters. In our review, special attention was paid to computationally efficient and mathematically elegant methods. In so doing we had tried to demonstrate the virtues of unified Incremental Graph (IG) approach. Incremental Graph is, in concept, a tool originally created for analysis and synthesis...
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The excitation controller with gain scheduling mechanism for synchronous generator control
PublikacjaThe power systems, including the synchronous generators and power systems networks, are complex nonlinear systems with configuration and parameters which change through time. That leads to electromechanical oscillations occurring in that system. Thus synchronous generator excitation controller must be capable of providing appropriate stabilization signal over broad range of operating conditions and disturbances. In this paper,...
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Energy-Aware Scheduling for High-Performance Computing Systems: A Survey
PublikacjaHigh-performance computing (HPC), according to its name, is traditionally oriented toward performance, especially the execution time and scalability of the computations. However, due to the high cost and environmental issues, energy consumption has already become a very important factor that needs to be considered. The paper presents a survey of energy-aware scheduling methods used in a modern HPC environment, starting with the...
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An Optimal Power Point Tracking Algorithm in a Solar PV Generation System
PublikacjaThe non-linearity in I-V characteristics of a PV panel requires to be operated at knee point to extract maximum power. In order to operate the panel at optimal point, maximum power point tracking (MPPT) algorithm is employed in the control structure. The main objective of MPP tracking is to keep the operation at knee point of I-V characteristics under varying condition of temperature and solar insolation. Under non uniform solar...
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Electrostatic Zipping Actuators—Analysis of the Pull-In Effect Depending on the Geometry Parameters
PublikacjaContinuous work on a new generation of actuators, referred to as artificial muscles, resulted in the initiation of work on electrostatic zipping actuators, the concept of which is derived from micro electro-mechanical devices. Despite partial knowledge of their basic operating parameters, a question remains whether electrostatic zipping actuators are able to meet the expectations in the context of generated forces and control possibilities....
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Modeling of Electrified Transportation Systems Featuring Multiple Vehicles and Complex Power Supply Layout
PublikacjaThe paper proposes a novel approach to modeling electrified transportation systems. The proposed solution reflects the mechanical dynamics of vehicles as well as the distribution and losses of electric supply. Moreover, energy conversion losses between the mechanical and electrical subsystems and their bilateral influences are included. Such a complete model makes it possible to replicate, e.g., the impact of voltage drops on vehicle...
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The use of LiFePO4 technology in autonomous PV systems
PublikacjaBattery manufacturing based on the flow of lithium ions is currently the fastest growing and the most promising technology. It is used in many applications - from the smallest electronic devices to the large-scale energy trays. However, in the PV systems lead-acid batteries are still the most commonly used. As they are much cheaper they also come with a number of significant disadvantages. It is anticipated that they will be replaced...
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Study on Combined Optical and Electrochemical Analysis Using Indium-tin-oxide-coated Optical Fiber Sensor
PublikacjaThe growing needs for fast and reliable sensing devices stimulate development of new technological solutions. In this work a new multi-domain sensing method is demonstrated where optical sensing device has been applied to enhance amount of data received during electrochemical analysis. Thin, optically transparent, high-refractive-index, and electrically conductive indium tin oxide (ITO) film was deposited using magnetron sputtering...
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Multifrequency Nanoscale Impedance Microscopy (m-NIM): A novel approach towards detection of selective and subtle modifications on the surface of polycrystalline boron-doped diamond electrodes
PublikacjaIn this paper, we describe the modification of Nanoscale Impedance Microscopy (NIM), namely, a combination of contact-mode atomic force microscopy with local impedance measurements. The postulated approach is based on the application of multifrequency voltage perturbation instead of standard frequency-by-frequency analysis, which among others offers more time-efficient and accurate determination of the resultant impedance spectra...
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Optimization of boron-doping process of titania nanotubes via electrochemical method toward enhanced photoactivity
PublikacjaIn this work, we were focused on the development of the electrochemical approach resulting in a stable boron doping of titania nanotubes. The doping procedure concerns anodic polarization of as-anodized titania in a H3BO3 solution acting as n boron precursor. The series of attempts were taken in order to elaborate the most beneficial doping conditions. The parameters of electrochemical doping allowing to obtain boron-doped titania...
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Assembly of 1D Granular Structures from Sulfonated Polystyrene Microparticles
PublikacjaBeing able to systematically modify the electric properties of nano- and microparticles opens up new possibilities for the bottom-up fabrication of advanced materials such as the fabrication of one-dimensional (1D) colloidal and granular materials. Fabricating 1D structures from individual particles offers plenty of applications ranging from electronic sensors and photovoltaics to artificial flagella for hydrodynamic propulsion....
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Optical investigations of electrochemical processes using a long-period fiber grating functionalized by indium tin oxide
Publikacjahe growing needs for fast and reliable sensing devices stimulate development of new technological solutions. In this work a new multi-domain sensing method is demonstrated where optical sensing device has been applied to enhance amount of data received during electrochemical analysis. Thin, optically transparent, high-refractive-index, and electrically conductive indium tin oxide (ITO) film was deposited using magnetron sputtering...
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Suspension and process parameters selection for electrophoretic deposition of Mn–Co spinel coating on steel interconnects
PublikacjaMetallic interconnect coatings, consisting of MnCo2O4 spinel, were effectively applied to Crofer 22 APU using the electrophoretic deposition (EPD) method in both H2O: ethanol and pure ethanol solvents. The primary goal of this method was to prevent chromium migration, minimize evaporation, and control the oxidation rate. The study aimed to assess the quality, adhesion, and thickness of the Mn–Co coating, with the objective of...
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Development of an Advanced Control Algorithm for DAB DC/DC Converters: Inrush Current Limitation and Enhanced Operation in Transient States.
PublikacjaThe publication addresses the dynamic state challenges encountered during development of a dual active bridge (DAB) converter within DC microgrid systems. The conventional startup method is identified as instigating a cascade of unfavorable outcomes, encompassing elevated starting current, transformer current asymmetry, DC voltage distortions, EMI and heightened thermal stress on semiconductor components. Additionally, it necessitates...
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Methods for biomaterials printing: A short review and perspective
PublikacjaPrinting technologies have opened larger windows of innovation and creativity to biomaterials engineers by providing them with the ability to fabricate complex shapes in a reasonable time, cost, and weight. However, there has always been a trouble with function adjusting in printing technologies in view of the multiplicity of materials and apparatus parameters. 3D printing, also known as additive manufacturing, revolutionized biomaterials...
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SiC-Based Power Electronic Traction Transformer (PETT) for 3 kV DC Rail Traction
PublikacjaThe design of rolling stock plays a key role in the attractiveness of the rail transport. Train design must strictly meet the requirements of rail operators to ensure high quality and cost-eective services. Semiconductor power devices made from silicon carbide (SiC) have reached a level of technology enabling their widespread use in traction power converters. SiC transistors oering energy savings, quieter operation, improved reliability...