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Search results for: GLASS TRANSITION TEMPERATURE
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EXHAUST GAS TEMPERATURE MEASUREMENTS IN DIAGNOSTICS OF TURBOCHARGED MARINE INTERNAL COMBUSTION ENGINES PART II DYNAMIC MEASUREMENTS
PublicationThe second part of the article describes the technology of marine engine diagnostics making use of dynamic measurements of the exhaust gas temperature. Little-known achievements of Prof. S. Rutkowski of the Naval College in Gdynia (now: Polish Naval Academy) in this area are presented. A novel approach is proposed which consists in the use of the measured exhaust gas temperature dynamics for qualitative and quantitative assessment...
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Thermo-mechanical reclaiming of ground tire rubber via extrusion at low temperature: Efficiency and limits
PublicationThermomechanical reclaiming of ground tire rubber (GTR) was performed at different temperatures (60, 120, and 180°C) using a co-rotating twin-screw extruder. Obtained samples were used in styrene-butadiene rubber (SBR) blends. As reference samples, SBR compounds containing untreated GTR were used. Curing characteristics, static and dynamic mechanical properties, and morphology of the obtained blends were determined. The results...
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Mechanism of Reduced Sintering Temperature of Al2O3–ZrO2 Nanocomposites Obtained by Microwave Hydrothermal Synthesis
PublicationA novel method to obtain Al2O3–ZrO2 nanocomposites is presented. It consists of the co-precipitation step of boehmite (AlO(OH)) and ZrO2, followed by microwave hydrothermal treatment at 270 ◦ C and 60 MPa, and by calcination at 600 ◦ C. Using this method, we obtained two nanocomposites: Al2O3–20 wt % ZrO2 and Al2O3–40 wt % ZrO2. Nanocomposites were characterized by Fourier transformed infrared spectroscopy, Raman spectroscopy,...
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High-Temperature Tensile Behaviour of GTAW Joints of P92 Steel and Alloy 617 for Two Different Fillers
PublicationThis study explores the high-temperature (HT) tensile rupture characteristics of a dissimilar gas-tungsten-arc-welded (GTAW) joint between P92 steel and Alloy 617, fabricated using ER62SB9 and ERNiCrCoMo-1 fillers. The high-temperature tensile tests were performed at elevated temperatures of 550 ◦C and 650 ◦C. An optical microscope (OM) and a field emission scanning electron microscope (FESEM) were utilized to characterize the...
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On the tendency of temperature and electric field dependences of interface recombination in P3HT:PCBM organic bulk heterojunction solar cells
PublicationWe demonstrate theoretical explanation of the temperature and electric field dependences of recombination coefficients in an organic P3HT:PCBM bulk heterojunction solar cell. Based onthe model of interface recombination, two analytical formulas describing the relative ratio of the interface (γI ) to the Langevin (γL) recombination coefficients have been derived. Our analysis indicates that the sign of parameters φT and φF determines...
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Impact of reclaimed asphalt pavement (RAP) on low-temperature properties of asphalt concrete
PublicationHot mix recycling is a practice which enables reusing materials from old asphalt pavements. Current Polish regulations allow usage of RAP only for binder and base courses, and its amount is limited. Asphalt mixtures with RAP material have to fulfil requirements stated for typical asphalt mixtures. The research presents low-temperature properties of twelve different asphalt concretes with RAP material, determined using three-point...
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Apparent molar volumes of divalent transition metal perchlorates and chlorides in N,N-dimethylacetamide.
PublicationZmierzono gęstości roztworów nadchloranów i chlorków manganu(II), kobaltu(II), niklu(II), miedzi(II) i cynku(II) w temperaturach 10, 20,25, 30, 40, 50 i 60(o)C. Obliczono pozorne objętości molowe. Wyznaczono graniczne wartości cząstkowych molowych objętości tych soli oraz odpowiednie rozszerzalności. Przeanalizowano i wyjaśniono różnice we właściwościach wolumetrycznych roztworów nadchloranów i chlorków.
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Apparent molar volumes of divalent transition metal chlorides and perchlorates in dimethyl sulfoxide solutions.
PublicationZmierzono gęstości roztworów nadchloranów i chlorków dwuwartościowych metali szeregu Mn(II)-Zn(II) w dimetylosulfotenku. Wyznaczone na drodze ekstrapolacji cząstkowe objętości molowe nadchloranów rozdzielono na udziały jonowe. Przeanalizowano wpływ pola ligandów na cząstkowe objętości molowe kationów. Przedstawiono związek między wartościami pozornych objętości molowych a stanami koordynacyjnymi soli w DMSO.
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Management of the transition spaces - comparison of the East European, West European and North American examples
PublicationArtykul dotyczy zagadnienia zagospodarowania przestrzeni stykowych pomiędzy strukturami portowymi i miejskimi w miastach portowych. Opisano w nim szereg przygkładów oraz zarysowano możliwe strategie zarządznaia tymi obszarami..
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MicroscopicA75sNMR study of the effect of impurities on the first-order spin-density-wave transition inBaFe2As2
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Origin of the liquid-liquid phase transition for trans-1,2-dichloroethylene observed by IR spectroscopy
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Family business as a breeding ground for nascent entrepreneurs. An insight into transition economy: the case of Poland
PublicationArtykuł przedstawia analizę zagadnienia zdolności firm rodzinnych do generowania postaw preprzedsiębiorczych na przykładzie Polski jako kraju o gospodarce transformującej się od centralnie sterowanej do rynkowej. Część empiryczna oparta jest wynikach pilotażowych badań przeprowadzonych na studentach pierwszego roku WZiE PG, które to wyniki posłużyły do stworzenia wstępnej wersji modelu opisującego determinanty procesu generowania...
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Adiabatic Compressibilities of Divalent Transition-Metal Perchlorates and Chlorides in N,N-Dimethylacetamide and Dimethylsulfoxide
PublicationZmierzono prędkości rozchodzenia się dźwięku roztworów nadchloranów i chlorków manganu(II), kobaltu(II), niklu(II), miedzi(II) i cynku(II) w N,N-dimetyloacetamidzie i dimetylosulfotlenku w temperaturze 298.15 K. Obliczono ściśliwości adiabatyczne i pozorne ściśliwości adiabatyczne badanych roztworów. Przedyskutowano wpływ anionu i rodzaju rozpuszczalnika na uzyskane graniczne wartości pozornych ściśliwości adiabatycznych soli.
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Mechanical properties and interfacial transition zone microstructure of concrete with waste basalt powder addition
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The K x-ray line structures of the 3d-transition metals in warm dense plasma
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Structural and catalytic properties of ceria layers doped with transition metals for SOFCs fueled by biogas
PublicationThe aim of this paper was to investigate an influence of the nanocrystalline Ce0.8A0.2O2-δ (A = Mn, Fe, Co, Ni, Cu) materials on the direct internal reforming of biogas in SOFC. Structural analysis of fabricated compounds has been done. An in-situ analysis of a composition of outlet gases from operating SOFC was performed using FTIR spectroscopy with simultaneous electrical tests. It was found out, that type of dopant strongly...
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The hydration of selected biologically relevant molecules – the temperature effect on apparent molar volume and compression
PublicationThe densities and sound velocities at T = (288.15, 293.15, 298.15, 303.15 and 308.15) K were measured for aqueous solutions of glycine, trimethylamine-N-oxide, taurine and N-methylacetamide. From these data, the apparent molar volumes, V the apparent molar isentropic compressions, KS,, and the Passynski hydration numbers of solutes were determined. The concentration dependencies of the calculated quantities, their limiting values...
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Diagnostic tolerances' evaluation method of the start-up exhaust temperature of a naval gas turbine
PublicationThe conducted investigations aimed to elaborate the method of marking diagnostic tolerances of the exhaust temperature of a gas turbine observed during engine's start-up process. The diagnostic tolerances were determined by means of statistical inference by creating the hypothesis about a normal distribution of the start-up exhaust temperature's dispersion in the initial operation moment, which was subsequently verified applying...
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Performance of the PEM fuel cell module. Part 2. Effect of excess ratio and stack temperature
PublicationThe paper describes a fuel cell based system performance under different thermal conditions. The system could be fed with bottled hydrogen or with very high purity hydrogen obtained from reforming of methanol. The system is based on two fuel cell units (1.2 kW each, produced by Ballard Power Systems Inc. and called Nexa), DC/DC converter, DC/AC inverter, microprocessor control unit, load unit, bottled hydrogen supply system and...
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Effect of bitumen characteristics obtained according to EN and Superpave specifications on asphalt mixture performance in low-temperature laboratory tests
PublicationThe paper aims to identify those characteristics of bitumen which have the greatest impact on asphalt mixture low-temperature performance. It was observed that stiffness and m-value of bitumen from BBR test were moderately related to stiffness and m-value of asphalt mixture obtained from 3 PB test. Simultaneously those rheological properties significantly impact on cryogenic stresses induced during TSRST test. The multiple regression...
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Measurement of temperature-dependent viscosity and thermal conductivity of alumina and titania thermal oil nanofluids
PublicationThe results of simultaneous measurements of dynamic viscosity, thermal conductivity, electrical conductivity and pH of two nanofluids, i.e. thermal oil/Al2O3 and thermal oil/TiO2 are presented. Thermal oil was selected as a base liquid because of possible application in ORC systems as an intermediate heating agent. Nanoparticles were tested at the concentration of 0.1%, 1% and 5% by weight within temperature range from 20°C to...
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The anisotropic photorefractive effect in lithium sulfo-phosphate glass system doped with nickel ions
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Graffiti saves birds: A year-round pattern of bird collisions with glass bus shelters
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Computer study of the lead-germanium alloy formation in over-reduced lead-germanate glass
PublicationPraca poświęcona jest badaniom dynamiczno-molekularnym struktury zredukowanego szkła ołowiowo-germanianowego o składzie 1Pb 1Ge 1GeO2. Analizie poddano strukturę matrycy szkła, GeO2 i osadzonej w niej fazy metalicznej, którą formują neutralne atomy Pb i Ge.
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The effect of low energy impact on the tensile strength of coated and uncoated glass particulate composites.
PublicationPrzedstawiono model teoretyczny pozwalający przewidywać poudarową wytrzymałość na rozciąganie w funkcji parametrów materiałowych i budowy kompozytu. Określono eksperymentalnie poudarową wytrzymałość na ściskanie kompozytów zbrojonych ciągłym włóknem szklanym w osnowie żywicy epoksydowej napełnianej mikrokulkami szklanymi w celu obniżenia skłonności do powstawania dużych zniszczeń przy udarze o niskiej energii. Wyniki eksperymentalnie...
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(Bi,Pb)-Sr-Ca-Cu-O glass-ceramics - superconductor and granular metal
PublicationW materiale o składzie (Bi,Pb)-Sr-Ca-Cu-O wskutek stosowania różnych warunków wytwarzania można otrzymać materiały o różnorodnych właściwościach. W efekcie wygrzewania materiał amorficzny częściowo krystalizuje. To powoduje wzrost rozmiaru i zawartości przewodzących i nadprzewodzących granul oraz zmniejszenie szerokości izolujących barier pomiędzy granulami. Zależność temperaturowa oporu słabo skrystalizowanego materiału jest funkcją...
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Characterization of Mechanical and Bactericidal Properties of Cement Mortars Containing Waste Glass Aggregate and Nanomaterials
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Evolution of the optical properties of chromium doped calcium tetraborate glass under high pressure
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Sestaveni Smerne Krivky Modulu Tuhosti Pro Zkoumani Nizkotrplotnich Vlastnosti (Developing of Stiffness Master Curve for Analysis of Low Temperature Properties)
PublicationV prispevku je predstaven novy postup pro sestrojeni smernych tuhostnich krivek. Nizkoteplotni vlastnosti asfaltove smesi byly stanoveny za vyuziti zkousky dotvarovani pri tribodovem ohybu. Motivem tohoto vyzkumu je skutecnost, ze metody hodnoceni nizkoteplotniho chovani asfaltovych smesi, nove zavedenych v Polsku, nejsou dostatecne. V zaveru jsou prezentovany smerne krivky tuhosti beznych asfaltovych smesi vyuzivanych v Polsku.
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MEASUREMENT OF TEMPERATURE-DEPENDENT VISCOSITY AND THERMAL CONDUCTIVITY OF ALUMINA AND TITANIA THERMAL OIL NANOFLUIDS
PublicationIn this study results of simultaneous measurements of dynamic viscosity, thermal conductivity, electrical conductivity and pH of two nanofluids, i.e. thermal oil/Al2O3 and thermal oil/TiO2 are presented. Thermal oil is selected as a base liquid because of possible application in ORC systems as an intermediate heating agent. Nanoparticles were tested at the concentration of 0.1%, 1% and 5% by weight within temperature range from...
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CPLFD-GDPT5: High-resolution gridded daily precipitation and temperature data set for two largest Polish river basins
PublicationThe CHASE-PL (Climate change impact assessment for selected sectors in Poland) Forcing Data–Gridded Daily Precipitation & Temperature Dataset–5 km (CPLFD-GDPT5) consists of 1951–2013 daily minimum and maximum air temperatures and precipitation totals interpolated onto a 5 km grid based on daily meteorological observations from the Institute of Meteorology and Water Management (IMGW-PIB; Polish stations), Deutscher Wetterdienst...
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Exhaust gas temperature measurements in diagnostic examination of naval gas turbine engines. Part I: Steady-state processes
PublicationThe article presents a possible method of detecting failures in the flow section and supply system of a naval gas turbine engine based on the exhaust gas temperature measured behind the gas generator. This temperature is a basic diagnostic parameter use for evaluating the technical state of the turbine engine in operation, and is monitored during engine start-ups, accelerations and decelerations of rotor units, and steady-load...
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Comparison of traditional district heating with low temperature district heating systems featuring organic Rankine cycle and heat pump
PublicationPaper presents a comparison between a traditional district heating system with conventional boilers as a source of heat and electricity purchases from power utilities and a low temperature DH system incorporating the CHP with organic Rankine Cycle providing electricity and local heat pump raising the temperature of the DH fluid to the required temperature in the dwelling, meaning that both heat and electricity are produced within...
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Temperature distribution in laser-clad multi-layers
PublicationW pracy przedstawiono porownanie rezultatów numerycznej symulacji rozkładu temperatur w warstwach nakładanych laserowo z wynikami pomiarów doświadczalnych. Otrzymano bardzo dobrą zgodność wyników co pozwala wnioskować, że przedstawiony model numeryczny może służyć jako efektywne narzędzie wstępnego doboru parametrów procesu laserowego nakładania warstw.
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Creep failure prediction of pipelines in elevated temperature
PublicationW pracy omówiono zastoswanie modelu konstytutytwnego pełzania pozwalającego na analizę trwałości metalowych ruruciągów pracujących w wysokich temperaturach. Zaprezentowano wyniki obliczeń opartych na metodzie elementów skończonych (MES) wykonanych z wykorzystaniem procedur użytkownika w komercyjnym programie MES. Porównano wyniki dla dwóch typów 4-węzłowych elementów powłokowych.
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Room-Temperature Ferromagnetism in InSb-Mn Nanowires
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Temperature distribution in laser-clad multi-layers
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Universal velocity and temperature profiles in bubbly flows.
PublicationW pracy przedstawiono model przepływu pęcherzykowego oparty na sumowaniu energii dysypacji pochodzącej od przepływu ścinającego bez pęcherzyków oraz dysypacji pochodzącej od obecności pęcherzyków. Rozwiązania równań różniczkowych opisujących model dają w wyniku uniwersalne profile prędkości i temperatur, które są bardzo przydatne w praktyce inżynierskiej.
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Temperature measurements in monitoring of large thrust bearings
PublicationW pracy przedstwiono krytyczną analizę aktualnych metod diagnostyki dużych hydrodnamicznych łożysk wzdłużnych hydrozespołów elektrowni wodnych. Wykazano niedostatki i zagrożenia płynące ze stosowania diagnostyki opartej na jednopunktowym pomiarze temperatury. Zaprezentowano wstępna koncepcję nowej metody diagnostycznej opartej na odwrotnym zagadnieniu przepływu ciepła (IPHC).
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Temperature measurements in monitoring of large thrust bearings
PublicationW pracy przedstwiono krytyczną analizę aktualnych metod diagnostyki dużych hydrodnamicznych łożysk wzdłużnych hydrozespołów elektrowni wodnych. Wykazano niedostatki i zagrożenia płynące ze stosowania diagnostyki opartej na jednopunktowym pomiarze temperatury. Zaprezentowano wstępna koncepcję nowej metody diagnostycznej opartej na odwrotnym zagadnieniu przepływu ciepła.
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Advanced Electromagnetic Metamaterials for Temperature Sensing Applications
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Low-temperature high-pressure cryogelation of nanooxides
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Low temperature luminescence of KMgF3:Eu2+ crystal
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Temperature evolution of the luminescence decay of Sr0.33Ba0.67Nb2O6: Pr3+
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Temperature Measurements in Monitoring of Large Thrust Bearings
PublicationW pracy przedstawiono krytyczną ocenę popularnego systemu diagnostyki dużych łożysk wzdłużnych (np. łożysk nośnych hydrogeneratorów), w którym stosowany jest jednopunktowy pomiar temperatury w klockach łożyskowych. Stwierdzono, że taki układ pomiarowy nie pozwala na bezpieczną eksploatację łożysk, ponieważ posiada bardzo duże opóźnienie czasowe, nie daje informacji o lokalnych zagrożeniach, nie pozwala racjonalnie ustalić poziomów...
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Parameters’ Identification of Perzyna and Chaboche Viscoplastic Models for Aluminum Alloy at Temperature of 120◦C
PublicationThe main purpose of this paper is the parameters identification of the Perzyna and the Chaboche models for the aluminum alloy at elevated temperature. The additional purpose is comparison of the results for these viscoplastic models. The results have been verified by the numerical simulation of the laboratory tests. The material parameters have been calculated on the basis of the uniaxial tension test. The determination of the...
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Exhaust gas temperature measurements in diagnostic examination of naval gas turbine engines. Part II. Unsteady processes
PublicationThe second part of the article presents the results of operating diagnostic tests of a two- and three-shaft engine with a separate power turbine during the start-up and acceleration of the rotor units. Attention was paid to key importance of the correctness of operation of the automatic engine load control system, the input for which, among other signals, is the rate of increase of the exhaust gas flow temperature. The article...
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LABORATORY STAND FOR INVESTIGATIONS OF THE QUICK - CHANGING TEMPERATURE OF GAS FLOWING IN THE PISTON COMPRESSOR OUTLET CHANNEL
PublicationThis paper presents a laboratory stand, created as a part of work on the doctor dissertation, intended for investigation of heat and flow processes taking place in the Espholin H3S piston compressor outlet channel. The test stand elements and their configuration within the stand are described. Discussed are also problems connected with the quick-changing measurement technique, solutions which have been proposed so far in that technology...
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FFT analysis of temperature modulated semiconductor gas sensor response for the prediction of ammonia concentration under humidity interference
PublicationThe increasing environmental contamination forces the need to design reliable devices for detecting of the volatile compounds present in the air. For this purpose semiconductor gas sensors, which have been widely used for years, are often utilized. Although they have many advantages such as low price and quite long life time, they still lack of long term stability and selectivity. Namely, environmental conditions have significant...
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The Impact of Homogeneity of High Modulus Asphalt Concrete Layer on Low-Temperature Cracking
PublicationDuring winter season of 2012 numerous transverse cracks developed in high-modulus asphalt concrete (HMAC) base of newly constructed motorway. Pavement cracked both in transverse joint locations and in the area between them. Research which was conducted during investigation of the causes and mechanisms of cracking consisted of: field examination, laboratory testing of specimens cored out of the existing pavement, computational analyses...