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The effect of preliminary creep-strain on material behavior under LCF tension/compression and pure torsion regimes
PublicationThis paper presents the results of experimental tests of monotonic tension and torsion, creep-rupture and preliminary creep at 200C and 300C, as well as low-cycle fatigue of 2024 T3511 aluminum alloy. The fatigue process was conducted at room temperature for uniaxial tension/compression and torsion. The as-received material and pre-deformed material were also investigated during creep at elevated temperature. Basic monotonic,...
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Wpływ temperatury na skład produktów pirolizy
PublicationPraca prezentuje wyniki badań pirolizy biomasy przy różnych temperaturach maksymalnych prowadzenia pro- cesu. Biomasą użytą w eksperymentach były zrębki brzozowe. Analizowano udziały masowe pięciu frakcji pro- duktów: karbonizatu, smół lekkich, smół ciężkich, wody oraz gazu pirolitycznego. Wykonano także analizy ciepła spalania poszczególnych frakcji w zależności od temperatury prowadzenia procesu. Eksperymenty wykonano przy pomocy...
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TOTAL CROSS SECTION MEASUREMENTS FOR ELECTRON SCATTERING ON METHYL FORMATE (HCOOCH3) MOLECULE: METHYLATION EFFECT
PublicationWe present the absolute total cross section (TCS) for electron scattering from the methyl formate (HCOOCH3) molecule measured in the 10-300 eV energy range, with electrostatic electron spectrometer working in the linear transmission mode. Comparison of TCS for the HCOOCH3 molecule with that measured earlier for the formic acid (HCOOH) compound manifests the methylation effect i.e. the response of the electron scattering dynamics...
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Design and Optimization of a Compact Planar Radiator for UWB Applications and Beyond
PublicationA compact monopole antenna for ultra-wideband (UWB) and beyond applications has been proposed. The radiator is based on the monopole topology. The super-wideband behavior has been achieved using a combination of spline-based modifications applied to the driven element, as well as utilization of a tapered feed and a slot-modified ground plane. The electrical performance of the structure has been tuned using a numerical optimization...
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Measurement method for capacitive sensors for microcontrollers based on a phase shifter
PublicationA complete measurement method dedicated to capacitive sensors has been developed. It includes the development of hardware (an analogue interface circuit for microcontrollers with built-in times/counters and analogue comparators) and software (a measurement procedure and a systematic error calibration (correction) algorithm which is based on a calibration dictionary). The interface circuit consists of a low-pass filter and a phase...
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Formaldehyde in various forms of atmospheric prepicitation and deposition from highly urbanized regions
PublicationOznaczono stężenie formaldehydu w próbkach różnych form opadów i osadów atmosferycznych pobieranych przez okres 12 miesięcy, w trakcie występowania opadu lub osadu atmosferycznego lub tuż po jego ustąpieniu, na terenie dwóch aglomeracji miejskich i wzdłuż dróg o różnym natężeniu ruchu. Formaldehyd wykryto w 303 próbkach z 500 pobranych (stężenia od 0.05 do 10.7 mg/dm3). Wyniki analiz potwierdziły iż:- opady i osady atmosferyczne...
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Effect of neoteric solvents on the activated sewage sludge activity
PublicationCiecze jonowe (ILs) cieszą sie rosnącym zainteresowaniem z uwagi na fakt, iż znajdują coraz więcej zastosowań jako alternatywa dla rozpuszczalników organicznych. W związku z zaistnieniem możliwości zastosowania ILs w nowych czystych technologiach nastała potrzeba zbadania ich toksyczności w stosunku do organizmów żywych i środowiska. Celem badań było oszacowanie wpływu cieczy jonowych na wyselekcjonowane mikroorganizmy osadu czynnego....
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Charge Transport in High-Entropy Oxides
PublicationThis work presents the results of research on the transport properties of the high-entropy BaZr1/8Hf1/8Sn1/8Ti1/8Y1/8In1/8Sm1/8Yb1/8O3–x perovskite oxide with special focus on proton transport. The presented study is part of broader work in which we focus on multiple different chemical compositions with the cation number varying from 5 up to 12 (in B-sublattice). The presence of proton defects is analyzed with thermogravimetry,...
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Układ awaryjnego zasilania oparty na ogniwach paliwowych PEFC zasilany wodorem i metanolem
PublicationGłównymi elementami badanego układu zasilania są dwa moduły ogniw paliwowych PEFC typu Nexa kanadyjskiej firmy Ballard o mocy 1,2 kW każdy. Badany układ został wyposażony w reformer paliwowy firmy Genesis Fueltech model 20 L, w którym do wytworzenia czystego wodoru wykorzystuje się unikatową metodę przetwarzania wodnego roztworu metanolu opartą na połączeniu wysokociśnieniowego reformingu parą wodną oraz użyciu membrany separującej....
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Photocatalytic activity of boron-modified TiO2 under visible light: The effect of boron content, calcination temperature and TiO2 matrix
PublicationPrzedstawiono wpływ temperatury kalcynacji (200, 300, 350, 400, 450 oraz 600oC) na fotoaktywność w świetle widzialnym (l> 400 nm) oraz właściwości powierzchniowe TiO2 modyfikowanego borem. B-TiO2 został przygotowany metodą impregnacji powierzchniowej. Jako prekursor bory wykorzystano ester trietylowy kwasu borowego (BATE). Charakterystyka otrzymywanych fotokatalizatorów obejmowała wyznaczenie powierzchni właściwej, właściwości...
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Jakość popłuczyn z płukania sieci wodociągowej metodą ukierunkowanego przepływu
Publicationprzedmiotem analizy jest jakość popłuczyn z płukania 80 km sieci wodociągowej w biłgoraju metodą ukierunkowanego przepływu w 2008 r. analizie poddano wyniki badań laboratoryjnych około 300 próbek w zakresie suchej pozostałości i zawartości żelaza ogólnego. największe wartości wskaźników odnotowano w trakcie pierwszej wymiany wody wraz z tendencją malejącą w kolejnych cyklach. bilans usuniętych zanieczyszczeń wskazuje, że masa suchej...
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Pyrolysis as an alternative for combustion of waste
PublicationProces pirolizy polega na rozkładzie materii organicznej w podwyższonej temperaturze w warunkach beztlenowych, dlatego może być on stosowany jako alternatywa lub uzupełnienie dla procesu spalania. Piroliza pozwala na uzyskanie substancji chemicznych z polimerów naturalnych i syntetycznych. W umiarkowanej temperaturze (300 - 500 ° C), można uzyskać wysokiej wydajności frakcji ciekłej, natomiast wysokie temperatury sprzyjają powstawaniu...
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Model of control plane of ASON/GMPLS network
PublicationASON (Automatic Switched Optical Network) is a concept of optical network recommended in G.8080/Y.1304 by ITU-T. Control Plane of this network could be based on GMPLS (Generalized Multi-Protocol Label Switching) protocols. This solution, an ASON control plane built on GMPLS protocols is named ASON/GMPLS. In the paper, we decompose the control plane problem and show the main concepts of ASON network. We propose a hierarchical architecture...
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Dylematy rozwoju krajowej elektroenergetyki
PublicationPolityka energetyczna Niemiec, obejmująca m.in. zmniejszanie zużycia energii elektrycznej, rozwój: energetyki wykorzystującej odnawialne źródła energii, rozproszonego skojarzonego wytwarzania energii elektrycznej i ciepła, tzw. inteligentnej sieci, współpracy z innymi systemami elektroenergetycznymi, modernizację i rozwój systemu przesyłowego energii elektrycznej, może być interesującym przykładem dla sąsiednich krajów. W Polsce...
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5-Bromo-2′-deoxycytidine—a potential DNA photosensitizer
PublicationA double-stranded oligonucleotide, 80 base pairs in length, was multiply labeled with 5-bromo-2′-deoxycytidine (BrdC) using polymerase chain reaction (PCR). The modified oligonucleotide was irradiated with 300 nm photons and its damage was assayed by employing DHPLC, LC-MS and denaturing polyacrylamide gel electrophoresis (PAGE). Two types of damage were demonstrated, namely, single strand breaks (SSBs) and intrastrand cross-links...
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Diethyl carbonate as a green extraction solvent for chlorophenol determination with dispersive liquid–liquid microextraction
PublicationThe principles of green analytical chemistry indicate that the search for greener organic solvents for extraction applications is crucial. In this study diethyl carbonate (DEC) is proved to be a green solvent, as it is relatively nontoxic, obtainable from renewable resources and biodegradable. Here it is applied as an extraction solvent for chlorophenol determination in water samples with dispersive liquid–liquid microextraction....
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A novel microstrip dual-layer rat-race coupler with compact size and enhanced bandwidth
PublicationMicrowave hybrid couplers are crucial components of mixers, phase shifters, amplifiers and other high-frequency systems. Conventional couplers are characterized by large size which limits their usefulness in modern applications. In this work, a novel compact rat-race coupler with enhanced bandwidth has been proposed. The structure consists of six compact microstrip resonant cells. It is implemented on two separate layers which permits...
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Badania statystyczne rezystancji izolacji silników szeregowych prądu stałego typu BGK pojazdów Dűwag N8C w wersji przed modernizacją, mające na celu ustalenie przyczyny występowania uszkodzeń tego typu silników – wyniki ekspertyzy
PublicationTramwaje serii N8C są największą liczebnie grupą pojazdów szynowych we flocie GAiT. Zgodnie z informacjami pozyskanymi od przewoźnika, w ostatnim czasie zaobserwowano zwiększenie częstości występowania uszkodzeń silników trakcyjnych tych pojazdów widoczne zwłaszcza dla wozów stacjonujących w zajezdni Nowy Port. Celem wyjaśnienia przyczyny tego stanu rzeczy wykonano statystyczne badania rezystancji izolacji uzwojeń wszystkich silników...
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Numerical simulation of natural convection of Glycol-Al2O3 nanofluids from a horizontal cylinder
PublicationThis paper deals with natural convection around a circular cylinder with constant heat flux in a cavity using computational fluid dynamics. As fluids ethylene glycol and a mixture of ethylene glycol with Al2O3 nanoparticles (mass concentrations of nanoparticles: 0.1% and 1%) are chosen. Rayleigh number ranges from 3104 to 3105. The nanofluids are modeled with single-phase approach. For the investigated range of nanoparticle concentration, the...
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Effects of social media communication on brand equity and brand purchase intention
PublicationThe author studied the effect of two different social media communication on brand equity and brand purchase intention. A total of 504 data sets were generated through a standardized online-survey and analysed with structural equation modeling. The results of the empirical study showed that both firm-created and user-generated social media communication influenced brand equity, consequently impacting brand purchase intention. This...
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Low-coherence sensors with nanolayers for biomedical sensing
PublicationIn this paper, we describe the fiber optic low-coherence sensors using thin film. We investigated their metrological parameters. Presented sensors were made with the use of standard telecommunication single mode optical fiber (SMF28). Different materials were applied to obtain thick layers, such as boron doped diamond, silver and gold. The thickness of layers used in the experiments ranged from 100 nm to 300 nm. Measurements were...
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Fabrication and photoactivity of organic-inorganic systems based on titania nanotubes and PEDOT containing redox centres formed by different Prussian Blue analogues
PublicationHerein, the heterojunction composed of an inorganic substrate: ordered hydrogenated titania nanotubes (H-TiO2NTs) and a deposited organic film: poly(3,4-ethylenedioxythiophene) (PEDOT) is reported. The conducting polymer is modified with different transition metal haxacyanoferrates (Mehcf), wherein as metal: copper, iron, cobalt and nickel are introduced. The presence of various metal centres provides characteristic redox activity...
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Experimental analysis of chip removing system in circular sawing machine
PublicationPaper presents analysis of the process of removing the wood chips generated during the cutting of the material on the circular sawing machine. The attention is focused on the upper cover of the chip removing system. Within the framework of the work a systematic experimental study of pressure distribution in the cover during operation of the selected rotational speed of saw blade with a diameter of 300 mm and 450 mm was carried...
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Synthesis, single crystal growth and properties of Sr5Pb3ZnO12
PublicationAbstract The novel Sr5Pb3ZnO12 oxide was synthesized by the solid-state reaction method. The crystal structure was studied by means of the powder x-ray diffraction Rietveld method and was found to be similar to 3 other previously known Sr5Pb3MO12 compounds (M = Co, Ni, Cu). Crystals of several hundred microns in size of the new phase were grown in molten sodium chloride and imaged using confocal optical and scanning electron microscopy....
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Novel method for metal-oxide glass composite fabrication for use in thermoelectric devices
PublicationA novel method for thermoelectric materials fabrication using a reduction of oxide precursors in hydrogen was reported. On the example of Bi-Sb, Bi-Sb-Te and Te-Ag-Ge-Sb compounds it was shown that this simple and easy method is suitable for fabrication of two-, three- and even multicomponent thermoelectric materials. It allows controlling a composition, microstructure and even type a of electrical charge carriers. As a result...
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Fabrication and properties of electrode material composed of ordered titania nanotubes and pEDOT:PSS
PublicationWe report on the two-stage preparation method of electrode material composed of titania nanotubes and poly(3,4-ethylenedioxythiopene):poly(2-styrenesulphonate) conductive polymer (pEDOT:PSS). Initially, titania nanotube arrays were produced by the anodization process of Ti substrate. Next, the polymer was potentiostatically deposited onto the thermally annealed nanotube arrays from the electrolyte containing monomer and counter...
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Formation enthalpies of LaLn׳O3 (Ln׳=Ho, Er, Tm and Yb) interlanthanide perovskites
PublicationHigh-temperature oxide melt solution calorimetry using 3Na2O·MoO3 at 802 °C was performed for interlanthanide perovskites LaLn׳O3 (Ln׳=Ho, Er, Tm and Yb) and lanthanide oxides (La2O3, Ho2O3, Er2O3, Tm2O3 and Yb2O3). The enthalpies of formation of these interlanthanide perovskites from binary lanthanide oxides at room temperature (25 °C) were determined to be −8.3±3.4 kJ/mol for LaHoO3, −9.9±3.0 kJ/mol for LaErO3, −10.8±2.7 kJ/mol...
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Spectral reflectance modeling of ZnO layers made with Atomic Layer Deposition for application in optical fiber Fabry-Perot interferometric sensors
PublicationSuitability of zinc oxide (ZnO) layers grown using Atomic Layer Deposition for operation in optical-fiber extrinsic Fabry-Perot sensors is investigated using a numerical model. Reflectance spectra obtained using the developed model indicate that the application of these layers in optical-fiber extrinsic Fabry-Perot sensors is difficult as it may require a source whose spectrum width is about 300 nm. A series of ZnO layers grown...
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Effect of Porosity on the Thermo-Mechanical Behavior of Friction-Stir-Welded Spark-Plasma-Sintered Aluminum Matrix Composites with Bimodal Micro- and Nano-Sized Reinforcing Al2O3 Particles
PublicationThe thermo-mechanical behavior of nanosized Al2O3 particles reinforcing aluminum was analyzed in the present paper. The material was prepared by spark plasma sintering and friction stir welding. The thermal stresses affecting the composite behavior during welding were modeled through COMSOL MultiPhysics, and the results were validated by the analyses of the composites’ mechanical properties. The spark-plasma-sintered materials...
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Mechanism of Solute and Thermal Characteristics in a Casson Hybrid Nanofluid Based with Ethylene Glycol Influenced by Soret and Dufour Effects
PublicationThis article models a system of partial differential equations (PDEs) for the thermal and solute characteristics under gradients (concentration and temperature) in the magnetohydrodynamic flow of Casson liquid in a Darcy porous medium. The modelled problems are highly non-linear with convective boundary conditions. These problems are solved numerically with a finite element approach under a tolerance of 10−8. A numerical algorithm...
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ZnO ALD-Coated Microsphere-Based Sensors for Temperature Measurements
PublicationIn this paper, the application of a microsphere-based fiber-optic sensor with a 200 nm zinc oxide (ZnO) coating, deposited by the Atomic Layer Deposition (ALD) method, for temperature measurements between 100 and 300°C, is presented. The main advantage of integrating a fiber-optic microsphere with a sensing device is the possibility of monitoring the integrity of the sensor head in real-time, which allows for higher accuracy during...
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Polarimetric studies of L-arginine-doped potassium dihydrogen phosphate single crystals
PublicationConoscopic interference patterns, channelled spectra and polarimetric techniques have been used for the characterization of pure and doped (with L-arginine amino acid) potassium dihydrogen phosphate (KDP) single crystals. Experimental polarimetric data have been obtained for the frequently used wavelength of 633 nm and for two close wavelengths of 532 and 543 nm in a high-accuracy dual-wavelength polarimeter. The measurement of...
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Electrochemical behaviour of Cr coating in acidic sulphate solution studied by cyclic polarization and impedance spectroscopy
PublicationOdporność korozyjną powłok chromowych w 0.01 M H2SO4 zbadano metodami woltamperometrii cyklicznej i spektroskopii impedancyjnej. Stwierdzono, że właściwości ochronne powłoki chromowej w kontakcie z powietrzem wzrastają dzięki tworzeniu się warstwy tlenkowej zapełniającej defekty w powłoce. W trakcie polaryzacji anodowej następuje częściowe roztwarzanie tej warstwy i penetracja agresywnego środowiska do podłoża (stali), co powoduje...
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Detection of corrosion process in marine environment by means of acoustic emission technique
PublicationW pracy przedstawiono możliwość detekcji procesu korozyjnego nieniszczącą metodą emisji akustycznej konstrukcji metalowych pracujących w środowisku wody morskiej. Pewną alternatywą wobec technik elektrochemicznych w monitorowaniu korozji zaproponowano nieniszczącą technikę emisji akustycznej. Emisja akustyczna znana jako zjawisko fizyczne i technika pomiarowa znalazły zastosowanie w detekcji korozji obiektów morskich. W związku...
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The increased level of cytochrome P450 isoenzyme CYP3A4 affects the cellular response in CHO cells upon antitumor imidazoacridinone C-1311 treatment
PublicationPochodna C-1311 to potencjalny związek przeciwnowotworowy, który dotarł do II fazy badań klinicznych. Związek ten ulega metabolicznej transformacji pod wpływem szczurzych i ludzkich białek mikrosomalnych. Wykazano, że białka cytochromu P450 odpowiadają za przemiany metaboliczne C-1311 jedynie w niewielkim stopniu. Z drugiej strony wykazano, że pochodna C-1311 jest inhibitorem białek cytochromu P450, zwłaszcza izoenzymu CYP1A2...
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Characterization of the fate of lipids in activated sludge
PublicationPrzeprowadzono doświadczenie wykazujące transformację lipidów w aerobowych warunkach osadu czynnego. Wykazano, że całkowitej, początkowej zawartości lipidów (2000 mg/l) nie udało się obniżyć do wartości niższej niż 300 mg/l. Jednakże, zawartość poszczególnych kwasów tłuszczowych uległa drastycznym zmianom, zarówno spadkowi, jak i wzrostowi podczas wszystkich faz wzrostu mikrobiologicznego. Obserwowane zmiany zawartości indywidualnych...
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Size effect in centrifuge cone penetration tests
PublicationOkreślenie efektu skali w badaniu wciskania stożka w zagęszczonych piaskach kwarcowych na podstawie badań modelowych w wirówce geotechnicznej. Badania przeprowadzono na dwóch piaskach kwarcowych przy przyśpieszeniach od 30g do 100g. Analizowano efekt skali związany ze stosunkiem średnicy modelu (mini-stożka) do średniej średnicy ziaren oraz wpływem poziomu naprężenia na opór stożka. Wpływ poziomu naprężenia powoduje powstanie geometrycznego...
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Organic-inorganic materials for fast charging-discharging processes in energy storage devices
PublicationPraca dotyczy materiału kompozytowego złożonego z poli(3,4-etylenodioksytiofenu) i heksacyjanokobaltanu żelaza. Materiał został otrzymany elektrochemicznie bezpośrednio na elektrodzie tytanowej metodą jednoetapowa z zawiesiny zawierającej monomer (EDOT) oraz Fe3[Co(CN)6]2 w postaci proszku. Warstwy pEDOT/FehcCo otrzymane potencjostatycznie ładunkiem od 0,6 do 1,5 C/cm2 charakteryzują się różną grubością (od 1,9 do 4 μm) zależną...
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The role of slowly biodegradable organic compounds in a full-scale biological nutrient removal activated sludge systems
PublicationThe aim of this study was to determine the immediate effects of slowly biodegradable substrates on the denitrification capability and phosphate release/uptake interactions for a full-scale biomass process from two large wastewater treatment plants (WWTPs) located in the cities of Gdansk and Gdynia (northern Poland). Since it is hard to distinguish the slowly biodegradable substrate in a direct way, a novel procedure based on batch...
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The Perception of an Entrepreneur’s Structural, Relational and Cognitive Social Capital among Young People in Poland - An Exploratory Study
PublicationThe goal of the current paper is to verify how an entrepreneur’s structural, relational and cognitive social capital levels are perceived by young people in Poland. The research involved a group of 374 undergraduate business students from a Polish university as participants. Participants completed a survey on entrepreneurial cognitions. It was found that participants assess the level of an entrepreneur’s social capital as relatively...
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Bimodal classification of English allophones employing acoustic speech signal and facial motion capture
PublicationA method for automatic transcription of English speech into International Phonetic Alphabet (IPA) system is developed and studied. The principal objective of the study is to evaluate to what extent the visual data related to lip reading can enhance recognition accuracy of the transcription of English consonantal and vocalic allophones. To this end, motion capture markers were placed on the faces of seven speakers to obtain lip...
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Modular power converter with superconducting magnetic energy storage for electric power distribution system — Analysis and simulation
PublicationThis paper describes selected issues concerning realization of energy storage system (ESS) designed to operate in power distribution system. This paper presents a modular approach of 300 kVA power converter operating with superconducting magnetic energy storage (SMES), which gives high dynamics together with high power and suitable capability for instantaneous energy storage. Analysis and simulation studies of selected power converter...
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Design and optimization of a novel miniaturized low-profile circularly polarized wide-slot antenna
PublicationThis paper presents a novel structure of a compact circularly polarized (CP) antenna. CP is obtained using a parasitic quasi-rectangular strip placed coplanar to the feedline. A ground plane perturbation combined with the asymmetric geometry of the coplanar waveguide ground planes is utilized to excite additional CP modes. All antenna dimensions are rigorously optimized to achieve the best possible performance in terms of the impedance...
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Numerical analysis of chip removing system operation in circular sawing machine using CFD software
PublicationPaper presents the analysis of the results of numerical simulations of the air flow process of wood chips removing system in the circular sawing machine. The attention is focused on the upper cover and bottom shelter of the chip removing system. Within the framework of the work a systematic numerical modeling of the air flow distribution in the cover and shelter during operation of the selected rotational speed of saw blade with...
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Influence of synthesis conditions on zinc oxide nanorode layer morphology
PublicationIn recent years one dimensional (1D) nanostructures (nanotubes, nanowires, nanoribbons and nanorods) have been widely studied. Among studied nano-materials, the greatest interest can be seen for zinc oxide (ZnO). However, there is still a need for simple, inexpensive and reproducible fabrication method. In the literature different fabrication methods can be found, most of them requires expensive equipment and involve complex...
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Structure and thermoelectric properties of Te/Ag/Ge/Sb (TAGS) materials obtained by reduction of melted oxide substrates
PublicationThe Ge0.77Ag0.1Sb0.13Te1alloy was fabricated by a novel two step route. For that purpose firstly the oxide reagents were melted at high temperature and quenched into pellets. After that pellets were milled to the powder and then reduced in hydrogen at various temperatures and for various periods of time. Energy dispersive X-ray analysis indicated the possibility of successful fabrication of stoichiometric thermoelectric materials...
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Running performance of an aerodynamic journal bearing with squeeze film effect
PublicationResults of theoretical and experimental studies concerning the performance of an aerodynamic journal bearing of which running is assisted by squeeze film ultrasonic levitation (SFUL) are presented in this paper. The SFUL mechanism not only can separate journal from the bearing at the start and stop phases of operation but also can significantly contribute to the dynamic stability of the bearing when it runs at speed. Computer calculations...
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Convenient and efficient N-methylation of secondary amines under solvent-free ball milling conditions
PublicationIn the present work, we report the development of a rapid, efcient, and solvent-free procedure for the N-methylation of secondary amines under mechanochemical conditions. After optimization of the milling parameters, a vibrational ball mill was used to synthesize 26 tertiary N-methylated amine derivatives in a short time of 20 min (30 Hz frequency) and high yields ranging from 78 to 95%. An exception was compounds having a hydroxyl...
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The effect of elevated temperature on LCF damage growth in 2024AA – Experiment and modeling
PublicationThis paper presents the results of experimental low-cycle fatigue (LCF) tests conducted on EN-AW 2024 alloy in T3511 temper at 100 ◦C, 200 ◦C and 300 ◦C. The material’s basic fatigue characteristics were determined, such as fatigue life curve and cyclic strain curve. Both the hysteresis loop and nature of fracture surfaces obtained in macro- and microscopic observations (scanning electron microscope, SEM) were accounted for. The...
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Structure and thermoelectric properties of Bi–Te alloys obtained by novel method of oxide substrates reduction
PublicationA novel method of thermoelectric materials fabrication has been developed. Oxide reagents have been melted at high temperature in air, quenched, milled to powder and reduced in hydrogen to form Bi–Te alloys. Structural and thermoelectric properties of samples have been investigated depending on initial composition and temperature of reduction process. Sample 25Bi2O3–75TeO2 reduced at 340 °C for 10 h has been found to be a p-type...