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Wyniki wyszukiwania dla: SOLID STATE POST-CONDENSATION
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Miniaturized Solid Phase Extraction techniques for different kind of pollutants analysis: State of the art and future perspectives – PART 1
PublikacjaSolid Phase Extraction (SPE) has been practiced in a modern form for more than half a century. It was constantly developing, driven by the analysts needs. These needs are coming from the importance to select an appropriate analytical method, which should have satisfactory accuracy, precision and sensitivity. In the case of sorbent-based microextraction techniques, the choice of miniaturized variants that meet these requirements...
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Miniaturized solid phase extraction techniques for different kind of pollutants analysis: State of the art and future perspectives – PART 2
PublikacjaDetermination of pollutants present in environmental samples at a low concentration level very often requires the analytical protocol that includes analytes isolation and/or enrichment prior to the final quantification. Miniaturized SPE offers an interesting alternative to LLE. Nowadays, many types of sorbents are available and can be used as selective materials for extraction of varied analytes in different kinds of samples. The...
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Application of vibrational spectroscopy, thermal analyses and X-Ray diffraction in the rapid evaluation of the stability in solid-state of ranitidine, famotidine and cimetidine
PublikacjaThis paper reports the study on applicability of Fourier transform infrared (FTIR), near-infrared (NIR) and Raman spectroscopy, differential scanning calorimetry (DSC) and X-ray diffraction (XRD) for the estimation of the chemical stability and photostability of histamine H2-receptor antagonist substances. Ranitidine hydrochloride (RAN), famotidine (FAM) and cimetidine (CIM) were tested and differences in sensitivity were measured...
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Solid State Conductivity of Optimized Polypyrrole Coatings on Iron Obtained from Aqueous Sodium Salicylate Solution Determined by Impedance Spectroscopy
PublikacjaIn this work the optimization procedure for corrosion resistance, surface analysis and electrical properties of PPy-Fe electrodes have been examined. Polypyrrole (PPy) film was electrochemically synthesized in a one step process from an aqueous solution of sodium salicylate and pyrrole with certain concentrations, different parameters and type of polymerization...
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A coordination chemistry study of hydrated and solvated cationic vanadium ions in oxidation states +III, +IV, and +V in solution and solid state
PublikacjaPrzedmiotem studiów jest chemia koordynacyjna solwatów jonów wanadu(III), oksowanadu(IV) jaki i dioksowanadu(V) w rozpuszczalnikach tlenowo-donorowych takich jak: woda, dimetylosulfotlenek (DMSO) oraz N,N'-dimetylopropylenomocznik (DMPU). Badania prowadzone były w roztworach ciekłych jak i w fazie stałej z wykorzystaniem absorpcji (EXAFS), rozproszenia (LAXS) jak i dyfrakcji promieniowania X. Analiza uzyskanych wyników wskazuje,...
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David Chiavacci, Simona Grano, Julia Obinger (eds.), Civil Society and the State in Democratic East Asia: Between Entanglement and Contention in Post High Growth
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5- epi -Incensole: synthesis, X-ray crystal structure and absolute configuration by means of ECD and VCD studies in solution and solid state
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Impact of High Pressure on Metallophilic Interactions and Its Consequences for Spectroscopic Properties of a Model Tetranuclear Silver(I)–Copper(I) Complex in the Solid State
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Thermally Stable and Deep Red Luminescence of Sr1–xBax[Mg2Al2N4]:Eu2+ (x = 0–1) Phosphors for Solid State and Agricultural Lighting Applications
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Agro-industrial byproducts for production of the immunosuppressant mycophenolic acid by Penicillium roqueforti under solid-state fermentation: Enhanced production by ultraviolet and gamma irradiation
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The structure of dimethylsulfoxide-solvated magnesium and calcium ions in solution and the solid state, and overview of the coordination chemistry of hydrated and solvated alkaline earth metal ions
PublikacjaOznaczono strukturę w stanie stałym i ciekłym solwatowanych jonów magnezu i wapnia w dimetylosulfotlenku. Stwierdzono, ze jony te tworzą sześciokoordynacyjne solwaty ze średnią długością wiązań Mg-O i Ca-O 2.062(4) i 2.303(5)A. Przegląd literaturowy ukazał, że jony berylu i magnezu we wszystkich rozpuszczalnikach tworzą odpowiednio cztero- i sześciokoordynacyjne solwaty, podczas gdy jony wapnia i strontu istnieją jako ośmiokoordynacyjne...
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A structural study of the hydrated and the dimethylsulfoxide, N, N´-dimet-hylpropyleneurea, acetonitryle, pyridine and N,N-dimethylthioformamide solvated nickel(II) ion in solution and solid state.
PublikacjaOznaczono strukturę w stanie stałym i ciekłym solwatowanego jonu niklu(II) w rozpuszczalnikach o różnych właściwościach donorowych: w wodzie, dimetylo-sulfotlenku, N,N`-dimetylopropylomoczniku, acetonitrylu, pirydynie i N,N-di-metylotioformamidzie. Stwierdzono, że nikiel(II) tworzy przede wszystkim sześciokoordynacyjne solwaty (woda, acetonitryl, DMTF). Jako solwat pięciokoordynacyjny istnieje tylko w dimetylopropylomoczniku....
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Cover Feature: Electronic Circular Dichroism Imaging (ECD i ) Casts a New Light on the Origin of Solid‐State Chiroptical Properties (Chem. Eur. J. 4/2022)
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Modeling of the alcohol dehydrogenase active site. Two different modes of alcohol binding in crystals of zinc and cadmium tri-tert-butoxysilanethiolates evidenced by X-ray diffraction and solid state vibrational spectroscopy
PublikacjaOpisano syntezę, struktury cząsteczkowe oraz widma FT-IR, 1H. 13C, 29Si, 113Cd NMR dziesięciu nowych, mieszanoligandowych kompleksów cynku i kadmu z ligandem tri-tert-butoksysilanotiolanowym i pochodnymi imidazolu. Za pomocą rentgenowskiej analizy strukturalnej i spektroskopii w podczerwieni udokumentowano dwa różne sposoby wiązania etanolu i metanolu w kryształach tych związków. Opisane kompleksy stanowią modele miejsca aktywnego...
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Modeling of the Alcohol Dehydrogenase Active Site: Two Different Modes of Alcohol Binding in Crystals of Zinc and Cadmium Tri‐tert‐butoxysilanethiolates Evidenced by X‐ray Diffraction and Solid‐State Vibrational Spectroscopy
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Effect of crystallization process at cryogenic conditions on the functional properties of the SUPERSTON alloy used in production the ship's propellers
PublikacjaThe purpose of this paper is to show results of laser treatment at cryogenic conditions of the SUPERSTON alloy used for ship's propellers. That modification process ought to bring beneficial changes of microstructure and residual stresses in the surface layer. During the laser remelting at cryogenic conditions the microstructure changes significantly. This is related to synergistic effects of the solidification rate, phase transformations...
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Effect of sintering temperature on electrochemical performance of porous SrTi1-xFexO3-δ (x = 0.35, 0.5, 0.7) oxygen electrodes for solid oxide cells
PublikacjaThis work evaluates the effects of the sintering temperature (800 °C, 900 °C, 1000 °C) of SrTi1-xFexO3-δ (x = 0.35, 0.5, 0.7) porous electrodes on their electrochemical performance as potential oxygen electrode materials of solid oxide cells. The materials were prepared by a solid-state reaction method and revealed the expected cubic perovskite structure. After milling, the powders were characterised by a sub-micrometre particle...
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Crystallographic study of self-organization in the solid state including quasi-aromatic pseudo-ring stacking interactions in 1-benzoyl-3-(3,4-dimethoxyphenyl)thiourea and 1-benzoyl-3-(2-hydroxypropyl)thiourea
Publikacja1-Benzoylthioureas contain both carbonyl and thiocarbonyl functional groups and are of interest for their biological activity, metal coordination ability and involvement in hydrogen-bond formation. Two novel 1-benzoylthiourea derivatives, namely 1-benzoyl-3-(3,4-dimethoxyphenyl)thiourea, C₁₆H₁₆N₂O₃S, (I), and 1-benzoyl-3-(2-hydroxypropyl)thiourea, C₁₁H₁₄N₂O₂S, (II), have been synthesized and characterized. Compound (I) crystallizes...
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Mixed-ligand complexes of zinc(II), cobalt(II) and cadmium(II) with sulfur, nitrogen and oxygen ligands. Analysis of the solid state structure and solution behavior. Implications for metal ion substitution in alcohol dehydrogenase
PublikacjaScharakteryzowano strukturę heteroleptycznych kompleksów cynku(II), kobaltu(II) i kadmu(II) z 2-(2'-hydroksyetylopirydyną), tri-tert-butoksysilanotiolem i metanolem. Przy pomocy widm UV-Vis i NMR stwierdzono szybką wymianę N-liganda w roztworach tych kompleksów. Wyznaczono przesunięcia 15N NMR 2-(2'-hydroksyetylopirydyny) w kompleksach cynku(II) i kadmu(II). Na podstawie widm w podczerwieni i obliczeń DFT oszacowano względną moc...
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Mixed-ligand complexes of zinc(II), cobalt(II) and cadmium(II) with sulfur, nitrogen and oxygen ligands. Analysis of the solid state structure and solution behavior. Implications for metal ion substitution in alcohol dehydrogenase
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Ceramic composites for single-layer fuel cells
PublikacjaComposite materials consisting of acceptor doped lanthanum orthoniobate electrolyte phase (La0.98Ca0.02NbO4) and Li2O:NiO:ZnO semiconducting phase were synthesized. The precursor powder of La0.98Ca0.02NbO4 was prepared in nanocrystalline (mechanosynthesis) and microcrystalline (solid-state synthesis) form. The composite can be applied in a single-layer fuel cell, because of the presence of two phases acting as an anode and a cathode...
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Properties of LiMnBO3 glasses and nanostructured glass-ceramics
PublikacjaPolycrystalline LiMnBO3 is a promising cathode material for Li-ion batteries. In this work, we investigated the thermal, structural and electrical properties of glassy and nanocrystallized materials having the same chemical composition. The original glass was obtained via a standard melt-quenching method. SEM and 7Li solid-state NMR indicate that it contains a mixture of two distinct glassy phases. The results suggest that the...
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Stabilization of the pyrochlore phase of Mn2Sb2O7 by double substitution
PublikacjaPolycrystalline samples of (Ce4+Mn2+3)(Ga3+Sb5+3)O14 were synthesized by a high-temperature solid-state reaction. In contrast with the parent Mn2Sb2O7 compound that adopts a rhombohedral or monoclinic structure at T > 600 °C, the pyrochlore structure of CeMn3GaSb3O14 is retained up to at least T = 1070°C. High-resolution synchrotron x-ray diffraction measurements show no sign of a superstructure or distortion from cubic symmetry...
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Effect of isovalent substitution on microstructure and phase transition of LaNb1−xMxO4 (M=Sb, V or Ta; x=0.05–0.3)
PublikacjaLaNb1−xMxO4 oxides with pentavalent elements of different ionic sizes (M=Sb, Ta and V, x=0.05–0.3) were synthesized by the solid state reaction method. Special interest was devoted to the antimony substituted lanthanum niobate which is a new material in this group. Rietveld analysis of the X-ray diffraction patterns was used to determine the influence of the material composition on unit cell parameters. On the basis of dilatometric...
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Novel luminescent calixarene-based lanthanide materials: From synthesis and characterization to the selective detection of Fe3+
PublikacjaCalix[n]arene-based coordination networks are an emerging class of materials with intriguing properties resulted from the presence of the cavity-like structure of the macrocycle and metallic nodes. In this work, four novel luminescent materials based on calix[4]arene-carboxylate and lanthanides (Eu3þ and Tb3þ) were prepared by two synthetic approaches, solvothermal (CDA-Eu-ST) and slow diffusion (CDA-Eu-RT, CDA-Tb-RT, CTA-Tb-complex)...
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Structural and spectroscopic investigation of new luminescent hybrid materials based on calix[4]arene-tetracarboxylate and Ln 3+ ions (Ln = Gd, Tb or Eu)
PublikacjaLanthanide-calixarene hybrid materials are of particular interest due to the combination of the interesting properties of the ligand cavity-like structure and the luminescent features of lanthanides. The aim of this study was to synthesize and investigate the photophysical properties of Eu3+, Tb3+ and Gd3+ hybrids based on calix[4]arene-tetracarboxylate. The preparation of two structurally different...
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Lead(II) coordination polymers with imidazole-4- and pyrazole-3-carboxylate isomeric linkers: Structural diversity and luminescence properties
PublikacjaUsing 1H-imidazole-4-carboxylic acid (4imCOOH) and 1H-pyrazole-3-carboxylic acid (3pyrCOOH) coordination polymers [Pb(4imCOO)2(H2O)]n (1) and [Pb2(3pyrCOO)4]n (2) were constructed. Obtained polymers were characterized via FT-IR, X-ray, PL and TG methods. The coordination polyhedron around Pb(II) in 1 is described as distorted pentagonal pyramid with hemidirected coordination sphere (based on DFT calculations). Compound 2 consists...
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The computational methods in the development of a novel multianalyte calibration technique for potentiometric integrated sensors systems
PublikacjaIn recent years, integration and miniaturization of ion-selective electrodes (ISEs) have brought many benefits resulting in the possibility of simultaneous determination of the ions concentration in small volume samples. One of the key problems related to the preparation of potentiometric integrated sensors systems (PISSs) is a calibration procedure due to the necessity to calibrate each particular sensor separately. The main aim...
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COMPARISON OF TWO MODELS OF CONDENSATION
PublikacjaIn the low-pressure part of steam turbine, the state path usually crosses the saturation line in penultimate stages. At least last two stages of this part of turbines operate in two –phase region. The liquid phase in this region in mainly created in the process of homogeneous and heterogeneous condensation. Several observations confirm however, that condensation often occurs earlier than it is predicted by theory i.e. before the...
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STRUCTURE AND MAGNETIC PROPERTIES OF Bi5Ti3FeO15 CERAMICS PREPARED BY SINTERING, MECHANICAL ACTIVATION AND EDAMM PROCESS. A COMPARATIVE STUDY
PublikacjaThree different methods were used to obtain Bi5Ti3FeO15 ceramics, i.e. solid-state sintering, mechanical activation (MA) with subsequent thermal treatment, and electrical discharge assisted mechanical milling (EDAMM). The structure and magnetic properties of produced Bi5Ti3FeO15 samples were characterized using X-ray diffraction and Mössbauer spectroscopy. The purest Bi5Ti3FeO15 ceramics was obtained by standard solid-state sintering...
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Giant Nernst effect in the incommensurate charge density wave state of P4W12O44
PublikacjaWe report the study of Nernst effect in quasi-low-dimensional tungsten bronze P4W12O44 showing a sequence of Peierls instabilities. We demonstrate that both condensation of the electronic carriers in the charge density wave state and the existence of high-mobility electrons and holes originating from the small pockets remaining in the incompletely nested Fermi surface give rise to a Nernst effect of a magnitude similar to that...
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Phosphorus concentration and availability in raw organic waste and post fermentation products
PublikacjaThe aim of the study was to determine the mobility of phosphorus forms in raw organic waste and from the solid and liquid fractions of digestate. To achieve the purpose of this study, the components (including livestock manure, agricultural waste, food waste, sewage sludge) and their post fermentation products were considered. Subsequently, the effect of the fermentation process on the mobility of phosphorus forms in post-fermentation fractions...
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Molecular geometry and optical activity of helically chiral N-nitrosamines derived from 1,2,3,4-tetrahydro- and 1,2,3,4,7,8,9,10-octahydro-1,10-phenanthroline
PublikacjaX-ray crystallographic analysis of the title N-nitrosamines revealed that they assume helical conformations in the solid state. Nitrosamines 1b and 2b were resolved by inclusion crystallization with optically active diols (TADDOLs). The absolute configuration of the guest molecules in the complexes 1b·3b and 2b·3b was assigned as M. The optical activity of the resolved compounds is manifested by their solid state CD spectra, which...
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Cation sensing by diphenyl-azobenzocrowns
PublikacjaMetal cations complexation and proton binding by 13- and 16-membered diphenyl-azobenzocrowns and diphenyl-hydroxyazobenzocrowns were studied in acetonitrile using spectroscopic methods: UV–vis spectroscopy, spectrofluorimetry, and 1H NMR spectroscopy. Phenyl moieties in benzene rings were found to affect binding strength alkali and alkaline earth metal cations and hydrogen ion, and affect tautomeric equilibrium of hydroxyazobenzocrowns....
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Mössbauer Spectroscopy and Magnetoelectric Effect Studies of Multiferroic Ceramics Based on BiFeO<sub>3</sub>
PublikacjaIn this work the results of investigations for (BiFeO3)x(BaTiO3)1-x and Bi1-xNdxFeO3 solid solutions are described. Samples were prepared by the conventional solid-state sintering method. X-ray diffraction, 57Fe Mössbauer spectroscopy, and magnetoelectric effect measurements were applied as complementary methods to determine the structure and magnetic properties of materials. For (BiFeO3)x(BaTiO3)1-x solid solutions Mössbauer...
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Reactions of Lithiated Diphosphanes R2P−P(SiMe3)Li (R = tBu and iPr) with [MeNacnacTiCl2·THF] and [MeNacnacTiCl3]. Formation and Structure of TitaniumIII and TitaniumIV β‑Diketiminato Complexes Bearing the Side-on Phosphanylphosphido and Phosphanylphosphinidene Functionalities
Publikacjaβ-Diketiminate complexes of TiIII-containing phosphanylphosphido ligands [MeNacnacTi(Cl){η2-P(SiMe3)- PR2}] (MeNacnac− = [Ar]NC(Me)CHC(Me)N[Ar]; Ar = 2,6- iPr2C6H3) were prepared by reactions of [MeNacnacTiCl2· THF] with lithium derivatives of diphosphanes R2P−P(SiMe3) Li (R = tBu, iPr) in toluene solutions. Surprisingly, reactions of [MeNacnacTiCl2·THF] with R2P−P(SiMe3)Li in THF solutions led to TiIV complexes containing phosphanylphosphinidene ligands...
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Electronic conductivity in the SiO2–PbO–Fe2O3 glass containing magnetic nanostructures
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Electrical properties and structure of lead-borate glass containing iron ions
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Influence of phonon-phonon coupling on superconducting state in honeycomb-type crystal lattice
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Multigap superconducting state in molecular metallic hydrogen
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Superconducting state in the atomic metallic hydrogen just above the pressure of the molecular dissociation
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The superconducting state in the B2H6 compound at 360GPa
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Description of the thermodynamic properties of BiH 5 and BiH 6 superconductors beyond the mean-field approximation
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Identification of the Inertia of Masses Flowing Water through the Pipes in Water Power Plants
PublikacjaW artykule przedstawiono sposób identyfikacji stałej czasowej reprezentującej bezwładność mas przepływającej wody w systemie rurociągów, w elektrowni wodnej. Przedstawiono strukturę modelu układu regulacji prędkości kątowej wykorzystywanego w procesie identyfikacji oraz przeprowadzono badania skuteczności działania metody w środowisku Matlab-Simulink. Opisano najistotniejsze wnioski wynikające z przeprowadzonych badań symulacyjnych.
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Selected problems of navigation of educational mobile robot
PublikacjaW artykule przedstawiono ideę sterowania układem autonomicznego robota mobilnego skonstruowanego do celów edukacyjnych. Opisano strukturę mechaniczną układu, układy sensorów oraz zakres możliwości wynikających z działania oprogramowania robota.
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The Behaviour Based Area Coverage of Unknown Environment by Autonomous Mobile Robot Using Modified ''The Way of the Ox'' Algorithm
PublikacjaPrzedstawiono propozycję rozwiązania zagadnienie całkowitego pokrycia terenu w układzie autonomicznego robota mobilnego. W tym celu zmodyfikowano algorytm "siewcy" oraz opracowano odpowiedni model układu, w środowisku Matlab-Simulink. Wykonano serię badań symulacyjnych, których najistotniejsze wyniki opisano w artykule.
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Localization of Mobile Robot Using Radio Waves
PublikacjaOpisano systemy lokalizacji robotów mobilnych wykorzystujące metody triangulacji i trilateracji, w przestrzeniach dwuwymiarowych. Zaproponowano metodę pomiaru odległości drogą radiową oraz przedstawiono uzyskane wyniki badań.
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Comparison the Accuracy of the Extrapolation Methods of the Time Phase Coincidence in Synchronization of Power Generating Units
PublikacjaW artykule opisano metody ekstrapolacji chwili zgodności fazowej napięć łączonych obiektów elektroenergetycznych. Przeprowadzono analizę porównawczą wybranych metod ekstrapolacji w równych warunkach pracy oraz przedstawiono najistotniejsze wyniki badań.
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Assessment of FSW Welds Made of Aluminum Alloy AW7075-T651.
PublikacjaThis paper summarizes the results of experimental studies in which the aluminum alloy AW7075-T651 was friction stir welded (FSW) using various combinations of process parameters (rotational - R and travel speed - T). Mechanical properties of the test welds were assessed by using static tensile test and Vickers hardness measurement. The temperature of the welded plates was monitored during welding by means of thermocouples placed...
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The Characteristic of Surface Layers on Austenitic Stainless SteelAfter Glow-discharge Nitriding Process.
PublikacjaThis paper presents investigation of surface layers. The diffusion layers were produced by using different parameters of reactive atmosphere (N2:H2). The research of the surface layers was performed using scanning electron microscope (SEM). The results of energy dispersive X-ray (EDX) analysis and X-ray diffraction (XRD) analysis are presented. Research reveals the influence of chemical constitution of reactive atmosphere on the...