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Search results for: INTENSIFICATION OF HEAT EXCHANGE
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Ocena zastosowania wybranych reguł wymiany narzędzi w systemie produkcyjnym
PublicationIn this paper, an integrated analytical and simulation modelling framework has been developed with the objective to explore total system planning and operational issues. It enables in particular structuring the alternative process flow in manufacturing systems and their extended investigation under different tool exchange rules with limited number of tool inventory. Simulation studies performed with the proposed rules in the environment...
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Enthalpies of formation of rare earth niobates, RE3NbO7
PublicationHigh-temperature oxide melt solution calorimetry was used to investigate energetics of a series of rare earth niobates RE3NbO7. All of investigated compounds were found to be stable in enthalpy in respect to their oxides. The enthalpy of formation from oxides becomes more exothermic as the size of the RE cation increases, a trend seen previously in other RE compounds including pyrochlores, perovskites, and phosphates. For smaller...
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Technical evaluation of marine auxiliary diesel engine on the basis of parameters synchronous generator
PublicationThe article presents a method for evaluating the technical condition of selected structural elements of the reciprocating internal combustion engine driving a synchronous generator. Th results of measurements of the electric generator parameters are the diagnostic information source. On this basis it is possible to determine the instantaneous angular speed marine engine crankshaft which, in turn, is the basis for reasoning about...
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Ancillary services to grids provided with distributed generation
PublicationThe paper introduces system for utilization of the customer-side generated energy. Additionally system can secure some ancillary services to grids. Those services include: current active filtering, load voltage stabilization and in case of grid voltage faults - uninterruptible load supplying (possible with energy storage device). Presented experimental results confirm flexibility of this arrangement in processes of power delivery...
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The morphology of vanadate glass-ceramics containing BaTiO3 measured with the use of AFM
Open Research DataThe structure of vanadate glass-ceramics doped with BaTiO3 was measured by AFM technique. Samples of the composition of x[BaO,TiO2]–(80 − x)V2O5–20Bi2O3 where x = 5, 10 and 15 in mol% were prepared by a conventional melt quenching technique. The melting was performed in alumina crucibles at the temperature of 1273 K–1373 K. The melts were poured on...
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Comparative study of operation of condensing and traditional boilers equipped with the ORC module for electricity generation
PublicationCondensing technology applied to boilers is to make full use of thermal energy contained in the fuel. That means that additionaly the heat from condensation of exhaust gases can be used for the purposes of heating the domestic hot water and to cover the demand for central heating. The study analyzed the operation of the "traditional" boiler equipped with the ORC module as the similar arrangement but with the condensing boiler....
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La 15 Nb x Ge 9 : a superstructure of the Mn 5 Si 3 structure type with interstitial Nb atoms
PublicationThe crystal structure and elementary properties of La15NbxGe9 are reported. Single-crystal X-ray diffraction,from a crystallite with only 0.12 Nb/formula unit, reveals that this compound, although transition metal deficient, crystallizes in a hexagonal “15-1-9”-like structure type, space group P63mc (no. 186) with lattice parameters a = b = 15.5017(2) Å, c = 6.9173(2) Å. The physical properties were examined by specific heat and resistivity...
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The use of liquid crystal thermography TLC and particle image velocimetry PIV in selected technical applications
PublicationNowadays, the energy cost is very high and this problem is carried out to seek techniques for improvement of the aerothermal and thermal (heat flow) systems performances in different technical applications. The transient and steady-state techniques with liquid crystals for the surface temperature and heat transfer coefficient or Nusselt number distribution measurements have been developed. The flow pattern produced by transverse...
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Burnout Investigation of Small Diameter Tubes Immersed in Nanofluids
PublicationThis paper deals with research into pool boiling critical heat flux (CHF) of water–Al2O3, water–TiO2 and water–Cu nanofluids on horizontal stainless steel tubes. The experiments were conducted under atmospheric pressure. Nanoparticles were tested at concentrations of 0.001%, 0.01%, 0.1% and 1% by weight. Ultrasonic vibration was used in order to stabilize the dispersion of the nanoparticles. Although dispersants were not used to...
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Networkig activities of general judiciary - from theory to practice
PublicationOver the last three decades, networks - as a field of research - have acquired a significant place among management sciences. Unfortunately, in the judiciary they have become a subject of more careful analyses only recently, which resulted in a large discrepancy of knowledge - both in theory and in its practical adaptation for the needs of the courts. In order to fill this cognitive gap, an attempt was made to identify levels of...
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An Impact of Environmental Disturbances on Combined Cycle Power Plant Control
PublicationCombined cycle power plants operate at thermal efficiency approaching 60 percent. In the same time their performance presents several problems that have to be addressed. E.g. gas turbines are very sensitive to backpressure exerted on them by the heat recovery steam generators as well as to ambient pressure and temperature.
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The Impact of Drying Conditions on the Surface Color Changes of Pine Wood
PublicationThe article presents the impact of drying process and selected parameters on the color changes on the surface of pine wood (Pinus sylvestris L.). Three predetermined process conditions (modes), mild, normal, and intensive, were investigated. The experiments were conducted using a semi-industrial scale dryer designed at the Gdańsk University of Technology with a loading capacity of 0.55 m3. The drying process was applied to pine...
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Inwestycje w surowce w połączeniu z polskim rynkiem kapitałowym, analiza ryzyka i efektywności
PublicationW artykule przedstawiono główne kategorie i rodzaje inwestycji w surowce. Cel opracowania to zbadanie czy inwestycja w Warszawski Indeks Giełdowy stanowi główny składnik optymalnego tj. cechującego się minimalnym ryzykiem portfela inwestycyjnego. Ponadto ustalono czy wspomniana inwestycja tradycyjna stanowi najważniejszy element portfela inwestycyjnego odznaczającego się najwyższą efektywnością. Stwierdzono, że wszystkie z 29 analizowanych...
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Innowacje jako przedmiot obrotu rynkowego
PublicationW artykule podjęto problem cech innowacji jako produktów, które na świecie, coraz częściej również w Polsce, stają się przedmiotem obrotu rynkowego. Różnią się zdecydowanie od produktów, oferowanych przez przedsiębiorstwa produkcyjno-usługowe na rynkach dóbr konsumpcyjnych, także gotowych dóbr przemysłowych. Kluczowe różnice wynikają z tego, że innowacja może być produktem - przedmiotem obrotu rynkowego już jako idea i koncepcja,...
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Thermal properties of strontium–borate glasses and glass-ceramics containing bismuth and vanadium oxides measured with DSC method
Open Research DataThermal properties of strontium–borate glasses and glass-ceramics containing bismuth and vanadium oxides was measured by DSC.
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CLAY MINERALS – MINERALOGY AND PHENOMENON OF CLAY SWELLING IN OIL & GAS INDUSTRY
PublicationAmong the minerals found in the earth's crust, clay minerals are of the widest interest. Due to the specific properties such as plasticity, absorbing and catalytic properties clay minerals are used in many industries (oil & gas, chemistry, pharmacy, refractory technology, ceramics etc.). In drilling, a phenomenon of swelling clays is frequently observed. It has an important impact on the cementing quality. During the last few decades...
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Quantum-state transfer in spin chains via isolated resonance of terminal spins
PublicationWe propose a quantum-state transfer protocol in a spin chain that requires only the control of the spins at the ends of the quantum wire. The protocol is to a large extent insensitive to inhomogeneity caused by local magnetic fields and perturbation of exchange couplings. Moreover, apart from the free evolution regime, it allows one to induce an adiabatic spin transfer, which provides the possibility of performing the transfer...
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Multi-Stage Video Analysis Framework
PublicationThe chapter is organized as follows. Section 2 presents the general structure of the proposed framework and a method of data exchange between system elements. Section 3 is describing the low-level analysis modules for detection and tracking of moving objects. In Section 4 we present the object classification module. Sections 5 and 6 describe specialized modules for detection and recognition of faces and license plates, respectively....
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The System of the Supervision and the Visualization of Multimedia Data for BG
PublicationMonitoring of country maritime border is an important task of the Border Guard. This task can be facilitated with the use of the technology enabling gathering information from distributed sources and its supervision and visualization. The system presented in the paper is an extension and enhancement of the previously developed distributed system map data exchange system. The added functionalities allow supplementation of map data...
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One Europe, one product, two prices - the price disparity in the EU
PublicationThe price dispersion in the European Union in the last fifteen years (1990-2005) is analysed. The analysis of price convergence is examined on aggregate and disaggregate levels. The macro approach is based on Comparative Price Level index calculated as the ratio between PPPs and exchange rate. The disaggregate analysis utilizesactual prices of 148 individual products sold in the 15 capital cities of the EU. The calculations comprise...
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The state of the art in the field of decrease the pollution in the South Baltic area
PublicationVarious form of human activity such as maritime transports, industrial activities, busy traffic, intensive farming and animal husbandry can have negative impact on natural marine environment. Baltic Sea catchment area is characterized by the high river water flux and wastewater treatment plants discharges. Additionally, the limited shallow connection to the North Sea results in little water exchange and residence time of approximately...
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TiN coating in ring-on-ring sliding with saline solution (0.9%) lubrication 5MPa, 0.1m/s specimn. #B48/#A45
Open Research DataWear tests in sliding friction of TiN coating on 1.4021 (EN 10088-1) heat treated stainless steel. Ring - on - ring contact in unidirectional sliding, TiN over TiN . Mean contact stress: 5MPa. Sliding velocity: 0,1 m/s. Mean friction radius: 9.5mm. Lubricant: SALINE SOLUTION (0.9%). Tribometer: PT-3. Overall test time till coating penetration 12 min....
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TiC coating in ring-on-ring sliding with saline solution (0.9%) lubrication 5MPa, 0.1m/s specimn. #B41/#A39
Open Research DataWear tests in sliding friction of TiC coating on 1.4021 (EN 10088-1) heat treated stainless steel. Ring - on - ring contact in unidirectional sliding, TiC over TiC . Mean contact stress: 5MPa. Sliding velocity: 0,1 m/s. Mean friction radius: 9.5mm. Lubricant: SALINE SOLUTION (0.9%). Tribometer: PT-3. Overall test time till coating penetration 9 min....
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CrN coating in ring-on-ring sliding with distlled water lubrication 5MPa, 0.1m/s specimn. #A23/#B22
Open Research DataWear tests in sliding friction of CrN coating on 1.4021 (EN 10088-1) heat treated stainless steel. Ring - on - ring contact in unidirectional sliding, CrN over CrN . Mean contact stress: 5MPa. Sliding velocity: 0,1 m/s. Mean friction radius: 9.5mm. Lubricant: DISTILLED WATER. Tribometer: PT-3. Overall test time till coating penetration 12 min. The...
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TiC coating in ring-on-ring sliding with distlled water lubrication 5MPa, 0.1m/s specimn. #B39/#A41
Open Research DataWear tests in sliding friction of TiC coating on 1.4021 (EN 10088-1) heat treated stainless steel. Ring - on - ring contact in unidirectional sliding, TiC over TiC . Mean contact stress: 5MPa. Sliding velocity: 0,1 m/s. Mean friction radius: 9.5mm. Lubricant: DISTILLED WATER. Tribometer: PT-3. Overall test time till coating penetration 3 min. The test...
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SiC coating in ring-on-ring sliding with distlled water lubrication 5MPa, 0.1m/s specimn. #B34/#A33
Open Research DataWear tests in sliding friction of SiC coating on 1.4021 (EN 10088-1) heat treated stainless steel. Ring - on - ring contact in unidirectional sliding, SiC over SiC. Mean contact stress: 5MPa. Sliding velocity: 0,1 m/s. Mean friction radius: 9.5mm. Lubricant: DISTILLED WATER. Tribometer: PT-3. Overall test time till coating penetration 3 min. The test...
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TiN coating in ring-on-ring sliding with saline solution (0.9%) lubrication 5MPa, 0.1m/s specimn. #A45/#B48
Open Research DataWear tests in sliding friction of TiN coating on 1.4021 (EN 10088-1) heat treated stainless steel. Ring - on - ring contact in unidirectional sliding, TiN over TiN . Mean contact stress: 5MPa. Sliding velocity: 0,1 m/s. Mean friction radius: 9.5mm. Lubricant: SALINE SOLUTION (0.9%). Tribometer: PT-3. Overall test time till coating penetration 12 min....
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TiC coating in ring-on-ring sliding with distlled water lubrication 5MPa, 0.1m/s specimn. #A41/#B39
Open Research DataWear tests in sliding friction of TiC coating on 1.4021 (EN 10088-1) heat treated stainless steel. Ring - on - ring contact in unidirectional sliding, TiC over TiC . Mean contact stress: 5MPa. Sliding velocity: 0,1 m/s. Mean friction radius: 9.5mm. Lubricant: DISTILLED WATER. Tribometer: PT-3. Overall test time till coating penetration 3 min. The...
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CrN coating in ring-on-ring sliding with saline solution (0.9%) lubrication 5MPa, 0.1m/s specimn. #A25/#B21
Open Research DataWear tests in sliding friction of CrN coating on 1.4021 (EN 10088-1) heat treated stainless steel. Ring - on - ring contact in unidirectional sliding, CrN over CrN . Mean contact stress: 5MPa. Sliding velocity: 0,1 m/s. Mean friction radius: 9.5mm. Lubricant: SALINE SOLUTION (0.9%). Tribometer: PT-3. Overall test time till coating penetration 9 min....
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CrN coating in ring-on-ring sliding with distlled water lubrication 5MPa, 0.1m/s specimn. #B22/#A23
Open Research DataWear tests in sliding friction of CrN coating on 1.4021 (EN 10088-1) heat treated stainless steel. Ring - on - ring contact in unidirectional sliding, CrN over CrN. Mean contact stress: 5MPa. Sliding velocity: 0,1 m/s. Mean friction radius: 9.5mm. Lubricant: DISTILLED WATER. Tribometer: PT-3. Overall test time till coating penetration 6 min. The test...
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SiC coating in ring-on-ring sliding with distlled water lubrication 5MPa, 0.1m/s specimn. #A33/#B34
Open Research DataWear tests in sliding friction of SiC coating on 1.4021 (EN 10088-1) heat treated stainless steel. Ring - on - ring contact in unidirectional sliding, SiC over SiC. Mean contact stress: 5MPa. Sliding velocity: 0,1 m/s. Mean friction radius: 9.5mm. Lubricant: DISTILLED WATER. Tribometer: PT-3. Overall test time till coating penetration 3 min. The test...
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The exemplary Kelvin probe microscopy studies of sensitized austenitic stainless steels
Open Research DataThe dataset summarizes the results of imaging the surface potential distribution using the Kelvin probe scanning technique. Due to the fact that the potential measured in this way is proportional to the electrochemical potential of metals or intermetallic phases, it is possible to assess the nobility differences of various alloy components. In the case...
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Photovoltaic module temperature stabilization with the use of phase change materials
PublicationThe worldwide growth of photovoltaics (PVs) has formed an exponential curve for more than four decades. During this period of time, PVs have evolved from a pure niche market of small-scale applications towards becoming a mainstream electricity source. The influence of temperature on the electrical parameters of crystalline silicon solar cells and solar modules is well described in the literature. In order to diminish these effects,...
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Evolution of charge density wave order in continuous solid solutions Lu(Ni1-xCox)C2
PublicationPseudo-ternary solid solutions, Lu(Ni1-xCox)C2 (0 ≤ x ≤ 1), were studied by means of powder X-ray diffraction, differential thermal analysis as well as electrical resistivity and heat capacity measurements. The crystal structure of the Lu(Ni1-xCox)C2 series, as investigated by means of X-ray powder diffraction, is of structure type CeNiC2, space group Amm2, Pearson symbol oS8. The structural analysis reveals a non-monotonous evolution,...
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Charge density wave and crystalline electric field effects in TmNiC2
PublicationSingle crystals of TmNiC2 were grown by the optical floating-zone technique and were investigated by x-ray diffraction (XRD), thermal expansion, electrical resistivity, specific heat, and magnetic susceptibility measurements. Single-crystal XRD reveals the formation of a commensurate charge density wave (CDW) characterized by a CDW modulation vector q2c = (0.5, 0.5, 0.5), which is accompanied by a symmetry change from the orthorhombic...
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Structure redetermination, transport and thermal properties of the YNi3Al9 compound
PublicationSingle crystals of completely ordered variant of the YNi3Al9 compound were grown by self-flux method with excess of aluminum. The crystal structure of the title compound was redetermined from single crystal X-ray diffraction data. The structure adopts ErNi3Al9 type, space group R32, parameters of the unit cell a = 7.2838(2) Å, c = 27.4004(8) Å. The growth of relatively large single crystals of the YNi3Al9 compound, having completely...
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Experimental Investigations on the Influence of Coil Arrangement on Melting/Solidification Processes
PublicationThe latent heat thermal energy storage units are very popular because of their high energy density and almost close to constant temperature during the charging/discharging. In the present study has been proposed new shell-and-coil geometry with a shifted coil position to enhance the performance of phase change thermal magazine. The experimental investigations have been performed both for the melting and solidification process of...
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The Course and the Effects of Agricultural Biomass Pyrolysis in the Production of High-Calorific Biochar
PublicationThe thermal pyrolysis of agriculture biomass has been studied in a fixed-bed reactor, wherethe pyrolysis was conducted at a steady temperature of 800◦C. This work analyses the pyrolysisproducts of six agricultural wastes: pistachio husks, walnut husks, sunflower hulls, buckwheat husks,corncobs and coconut shells. The conducted research compared examples of large waste biomassstreams from different parts of the world as a potential...
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DEPO: A dynamic energy‐performance optimizer tool for automatic power capping for energy efficient high‐performance computing
PublicationIn the article we propose an automatic power capping software tool DEPO that allows one to perform runtime optimization of performance and energy related metrics. For an assumed application model with an initialization phase followed by a running phase with uniform compute and memory intensity, the tool performs automatic tuning engaging one of the two exploration algorithms—linear search (LS) and golden section search (GSS), finds...
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Prediction of coking dynamics for wet coal charge
PublicationA one-dimensional transient mathematical model describing thermal and flow phenomena during coal coking in an oven chamber was studied in the paper. It also accounts for heat conduction in the ceramic oven wall when assuming a constant temperature at the heating channel side. The model was solved numerically using partly implicit methods for gas flow and heat transfer problems. The histories of temperature, gas evolution and internal...
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Elementary analysis and energetic potential of the sludge from the Gdynia Dębogórze and Lębork wastewater treatment plants
PublicationThe paper aims to show the results of the elementary analysis of the sewage sludges from wastewater treatment plants in Gdynia Dębogórze and Lębork as well as measurements of the heat of combustion and the calculated calorific values according to regulation PN-93/Z-15008, taking into account water content and the composition of sewage sludge at different utilisation stages. The results presented in this paper are based on the analysis...
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Corrosion behavior of hydrogen charged super duplex stainless steel welded joints
PublicationThe electrochemical behavior of the weld metal, heat-affected zone (HAZ), and base material of super duplex stainless steel (SDSS) welded joints, made with the application of flux-cored arc welding (FCAW) and submerged arc welding (SAW), were investigated with the use of metallographic examinations (optical microscopy and scanning electron microscopy), potentiodynamic polarization measurements and total hydrogen content determination...
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Thermal and hydraulic phenomena in boundary layer of minijets impingement on curved surfaces
PublicationPresented work considers flow and thermal phenomena occurring during the single minijet impingement on curved surfaces, heated with a constant heat flux, as well as the array of minijets. Numerical analyses, based on the mass, momentum and energy conservation laws, were conducted, regarding single phase and two-phase simulations. Focus was placed on the proper model construction, in which turbulence and boundary layer modeling...
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Superconductivity in the intermetallic compound Zr5Al4
PublicationPolycrystalline Zr5Al4 was synthesized using the arc-melting method. Powder X-ray diffraction confirms the previously reported crystal structure of the Ti5Ga4-type P63/mcm with lattice parameters: a = 8.4312(6) A , and c = 5.7752(8) A . Electrical resistivity and low-temperature magnetic susceptibility measurements indicate that Zr5Al4 exhibits superconducting behavior below 2 K. The normalized heat capacity jump at Tc= 1.82 K...
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Thermal analysis of Magnetohydrodynamics (MHD) Casson fluid with suspended Iron (II, III) oxide-aluminum oxide-titanium dioxide ternary-hybrid nanostructures
PublicationThis study is carried out to enhance and analyze the thermal performance of non-Newtonian Casson fluid by immersing Ternary hybrid nanoparticles Fe3O4-Al2O3-TiO2 uniformly. To model the behaviour of such complex phenomena mathematically, a system of complex transport differential equations is developed by utilizing a non-Fourier heat transfer model for energy transport. The non-dimensional system of transport equations involving...
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Evaluation of structural and electrical properties of multicomponent spinel oxide thin films deposited via spray pyrolysis technique
PublicationThis work reports the preparation of (Mn,Co,Fe,Ni,Cr)3O4 high-entropy spinel oxide in the form of a ~ 500 nm thin film utilising a facile spray pyrolysis technique. The structural and electrical properties of the layers were characterised after exposure to temperatures in the range of 400–900 ◦C. The as-deposited layers were amorphous, and crystallised upon heat treatment at 500 ◦C. Microstructural analyses proved a homogeneous...
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Single crystal growth and physical properties of MCo2Al9 (M= Sr, Ba)
PublicationSingle crystals of SrCo2Al and BaCo2Al9 were grown using a self-flux method. A LeBail analysis of the powder X-ray diffraction patterns show that both compounds crystallize in a hexagonal (P6/mmm) crystal structure with lattice parameters: a = 7.8995(1) Å, c = 3.9159(1) Å for SrCo2Al9, and a = 7.9162(2) Å, c = 3.9702(1) Å for BaCo2Al9 aluminide. The low temperature analysis of the heat capacity measurements give a Sommerfeld...
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Crystal Growth, Structure, and Magnetism of the 2D Spin 1/2 Triangular Lattice Material Rb3Yb(PO4)2
PublicationThe single-crystal growth, crystal structure, heat capacity, and anisotropic magnetization characterization of Rb3Yb- (PO4)2, a Yb-based triangular lattice material, are presented. Single-crystal X-ray diffraction shows that Rb3Yb(PO4)2 exhibits [Yb(PO4)]∞ layers, with the Yb in an ordered plane of equilateral triangles. One phosphate group oxygen that is not a near neighbor of the magnetic Yb displays positional disorder. The...
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A concept for reducing PM 10 emissions for car brakes by 50%
PublicationWith regard to airborne particles with an aerodynamic diameter of less than 10 μm (PM10), in countries in the European Union, the mass of brake emissions equals approximately 8–27% of the total traffic-related emissions. Using a research methodology combining tests at different scale levels with contact mechanics simulations and PM10 chemical characterization, the REBRAKE EU-financed project had the following aims: i) to demonstrate...
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On dynamic modeling of piezomagnetic/flexomagnetic microstructures based on Lord–Shulman thermoelastic model
PublicationWe study a time-dependent thermoelastic coupling within free vibrations of piezomagnetic (PM) microbeams considering the flexomagnetic (FM) phenomenon. The flexomagneticity relates to a magnetic field with a gradient of strains. Here, we use the generalized thermoelasticity theory of Lord–Shulman to analyze the interaction between elastic deformation and thermal conductivity. The uniform magnetic field is permeated in line with...