Search results for "Thermal transfer"

showing 5 items of 5 documents

Size dependent carrier thermal escape and transfer in bimodally distributed self assembled InAs/GaAs quantum dots

2012

We have investigated the temperature dependent recombination dynamics in two bimodally distributed InAs self assembled quantum dots samples. A rate equations model has been implemented to investigate the thermally activated carrier escape mechanism which changes from exciton-like to uncorrelated electron and hole pairs as the quantum dot size varies. For the smaller dots, we find a hot exciton thermal escape process. We evaluated the thermal transfer process between quantum dots by the quantum dot density and carrier escape properties of both samples. © 2012 American Institute of Physics.

DYNAMICSMaterials scienceAtmospheric escapeCondensed matter physicsExcitonGeneral Physics and AstronomyElectronRate equationThermal transferEPITAXYCondensed Matter::Mesoscopic Systems and Quantum Hall EffectGallium arsenidechemistry.chemical_compoundCondensed Matter::Materials SciencechemistrySTATESself assembled quantum dots rate equations model carrier escape propertiesQuantum dotQuantum dot laserLUMINESCENCEPHOTOLUMINESCENCE
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Methods for Determining the Thermal Transfer in Phase-Changing Materials (PCMs).

2020

A very important issue that needs to be solved as simply and correctly as possible is how to establish the thermal performance of phase-changing materials (PCM). The undertaken researches have analyzed the values of the thermal performances of the PCM taking into account the method of finite elements and the experimental research, respectively, based on a modern measurement system that was designed and implemented. Butyl stearate which has been encapsulated through complex coacervation in polymethyl methacrylate has been used as a PCM. Samples were made containing 10%, 20%, 30% and 40% PCM, respectively, within their structure. The research has established that at both the hot plate and the…

FEMMaterials sciencePolymers and Plastics020209 energyInterface (computing)System of measurementFlow (psychology)thermal transfer measurementMechanical engineeringbutyl stearate02 engineering and technologyGeneral ChemistryThermal transfer021001 nanoscience & nanotechnologyTemperature measurementFinite element methodArticlepolymethyl methacrilatlcsh:QD241-441lcsh:Organic chemistryPhase (matter)PCMThermal0202 electrical engineering electronic engineering information engineering0210 nano-technologyPolymers
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Thermal properties of multiferroic Bi1−xEuxFeO3 (х = 0–0.40) ceramics

2017

Abstract A study of thermal diffusion, heat capacity and thermal conductivity of multiferroic Bi 1−x Eu x FeO 3 (x = 0–0.4) within the range of 130–1200 K is reported. Modifying by admixture of Eu is found to change substantially the thermal anomalies of diffusion and thermal conductivity of the antiferromagnetic phase transition, to increase heat capacity over a wide range of temperatures and to shift the antiferromagnetic transition temperature. The excess heat capacity is shown being related to Schottky effect of three-level states. The mechanisms dominating thermal transfer of phonons at the phase transition and dependence of the mean free path of phonons on the temperature are determin…

Thermal effective massPhase transitionMaterials scienceCondensed matter physicsMechanical EngineeringTransition temperatureMetals and Alloys02 engineering and technologyThermal transfer021001 nanoscience & nanotechnologyThermal conductionThermal diffusivity01 natural sciencesHeat capacityThermal conductivityMechanics of Materials0103 physical sciencesMaterials Chemistry010306 general physics0210 nano-technologyJournal of Alloys and Compounds
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Historical mortars dating from OSL signal of fine grain fraction enriched in quartz

2013

Abstract In the last years the mortar dating through Optically Stimulated Luminescence (OSL) techniques has become a viable support for chronological estimations (date of construction or restoration episodes) of historical buildings. However, the dating of mortar has still open issues mainly regarding the assessment of the bleaching degree of quartz, the analysis of the OSL processes for this type of samples and the need to do appropriate tests for the most correct evaluation of the equivalent dose. This paper discusses the results obtained by OSL dating (blue diode stimulation) on the polymineral fine grain phase, enriched in quartz, extracted from lime mortar samples collected from differ…

BrickThermoluminescence datingOptically stimulated luminescenceMineralogyThermal transferengineering.materialThermoluminescenceSettore FIS/07 - Fisica Applicata(Beni Culturali Ambientali Biol.e Medicin)Earth and Planetary Sciences (miscellaneous)engineeringMortarLime mortarQuartzGeologyhistorical mortars luminescence dating partial bleaching test preheating test age model
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Heat solitons and thermal transfer of information along thin wires

2020

Abstract The aim of this paper is to consider soliton propagation of heat signals along a cylinder whose heat exchange with the environment is a non-linear function of the difference of temperatures of the cylinder and the environment and whose heat transfer along the system is described by the Maxwell–Cattaneo equation. To find the soliton solutions we use the auxiliary equation method. Our motivation is to obtain and compare the speed of propagation, the maximum rate of information transfer, and the energy necessary for the transfer of one bit of information for different solitons, by assuming that a localized soliton may carry a bit of information. It is shown that a given total power (e…

Fluid Flow and Transfer ProcessesPhysicsInformation transferThermal solitonsMechanical EngineeringCharacteristic equation02 engineering and technologyThermal transferMechanics021001 nanoscience & nanotechnologyCondensed Matter Physics01 natural sciences010305 fluids & plasmasHeat wave0103 physical sciencesHeat transferRadiative transferRadiative transferCylinderInitial value problemSolitonMaxwell–Cattaneo law0210 nano-technologySettore MAT/07 - Fisica MatematicaAuxiliary equation methodInternational Journal of Heat and Mass Transfer
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