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Flash sintering of ceramic powders is a complex process that involves electric, thermal and mechanical phenomena. Modelling should help to better understand and control it, with a view to producing safe and homogeneous parts. A finite element model that couples all relevant phenomena, including the densification and shrinkage of the sintering material, has been worked out for this purpose. This model is used here to investigate the flash sintering of disk-shaped parts. Particular attention is paid to the appearance and growth of heterogeneities within the part, known as hot spots, which are highly dependent on material and process parameters. Leads are provided for limiting the development of such heterogeneities. [ABSTRACT FROM AUTHOR]

Flexible wearable strain sensors are becoming increasingly popular due to their ability to monitor physiological signals and to detect motion in a wide range of applications. However, the development of strain sensors with high sensitivity and wide sensing range remains a challenge. Herein, a film-nanowire double sensoring layer structure (FNDLS) crack strain sensor with high sensitivity, wide strain range and fast response is proposed. The FNDLS with hierarchical synergistic are integrated onto fabrics using a heat pressing process. The FNDLS has a very low initial resistance and a high density of channel cracks to have the high sensitivity of the strain sensor and to extend the strain range of the strain sensor through the synergistic bridging effect of the AgNWs. Due to this structure, the sensitivity of the sensor can reach 70945 , the strain range can reach about 40 %, and response time is less than 129 ms. Furthermore, the sensor demonstrates exceptional cycling stability and favourable frequency characteristics. Its superior performance makes it suitable for monitoring pulse waves and detecting motion through smart clothing. [Display omitted] • Strain sensors with a double conductive layer based on heat pressing method. • Strain sensors has ultra-high sensitivity, wide strain range and fast response. • Sensor can be used for pulse wave monitoring and fitness motion correction. [ABSTRACT FROM AUTHOR]

• A thermal and thermodynamic code aimed at describing the physics in LNG carrier tanks is developed. • Complex physical phenomena in LNG carrier tanks including ship motion are taken into account. • Operational Boil-off is simulated. This paper describes the numerical method implemented in Gaztransport & Technigaz specific-purpose thermal and thermodynamic code for complex physical phenomena in Liquefied Natural Gas (LNG) carrier tanks. The code is zero-dimensional and is used for LNG industrial applications and research activities in several fields related to Boil-off Gas (generation, consumption, optimization, etc.). The set of equations considered consists of the LNG and NG mass and energy conservation equations completed with equation of state and equations for LNG aging modeling. An explicit time-marching scheme with multiple-order methods is used. Specific effort has been put into the fast computation of the thermodynamic and transport properties of LNG. The implemented physical approaches have been validated by operational data. Better management of Boil-off represents a significant operational challenge for players in the LNG chain. Industrial applications illustrate important aspects of physical modeling such as saturation properties, thermal layer and sloshing. These examples also demonstrate the capability of the code to tackle a large variety of LNG carrier operating conditions and tank geometries. [ABSTRACT FROM AUTHOR]

Abstract We utilize thermal transfer technology to suggest a novel baking process for the emitting layer (EML) of residual-solvent-free organic light-emitting diodes (OLEDs). We deposited the EML onto an intermediate substrate using a conventional spin-coating process, after which the EML was transferred to the device by evaporating the EML through heating of the intermediate substrate. The EML films were fully transferred from an intermediate substrate to the target substrate at a temperature exceeding 350 °C under both a low vacuum of ∼10−3 Torr and a high vacuum of ∼10−6 Torr. The quantity of residual solvent was carefully investigated using gas chromatography-mass spectrometry (GC-MS) and nuclear magnetic resonance (NMR) analysis methods. While residual solvent peaks were found to exist 1.69 min after the beginning of the measurement process in the conventional spin-coating EML films despite the baking condition of 150 °C, solvent peaks were not observed in the EML films created with the novel baking process under conditions identical to those used in the GC-MS measurement. Moreover, according to the NMR analysis, the solvent peak of toluene at 2.3 ppm was not found in the thermally transferred EML films. Furthermore, we investigated the device performance capabilities between samples fabricated using the conventional baking process and those created with the novel thermal transfer process. In spite of low pressure of ∼10−3 Torr, the current efficiency and the lifetime of the OLED device created via the thermal transfer process were enhanced owing to the elimination of the residual solvent. Graphical abstract Image 10778 Highlights • The quantity of residual solvent in emitting layer was carefully investigated using GC-MS and NMR analysis methods. • Through the conventional spin-coating and baking process, residual organic solvents could not be eliminated completely. • The residual solvent was not detected in the thermal transferred-EML film fabricated by our novel baking process. • Performance of OLED device created via the novel baking process was enhanced owing to the elimination of the residual solvent. [ABSTRACT FROM AUTHOR]

Highlights • Ambient temperature effects on SCDAs were explored for 3 pipe diameters. • Samples were tested in a water bath and/or a constant temperature chamber at 10 °C. • The largest pipe showed peak hydration heat 50% greater than the water temperature. • The smallest pipe showed peak hydration heat 22% greater than the water temperature. • Traditional pipe tests fail to account for the influence of thermal transfer. Abstract This paper explores thermal transfer effects in Soundless Chemical Demolition Agents (SCDA). In a 10 °C water bath, quadrupling the volume of SCDA in a pipe accelerated peak hydration onset and resulted in a 700% increase in expansive pressure and a 20% increase in volumetric expansion. An equivalent sample in a constant temperature chamber showed an almost 5 °C greater hydration heat than in the water bath, which resulted in a six-fold expansive pressure difference after 4 days of testing and an order of magnitude more pressure in the first 24 h, thereby demonstrating limitations of previous SCDA experimental work and providing a temperature-based reason for discrepancies between large-scale testing and manufacturers’ predictions. Since most construction projects have scheduling requirements, understanding how to achieve sufficiently high pressures within a single work shift is important for evaluating the field viability of SCDAs on a particular project. [ABSTRACT FROM AUTHOR]

Heat treatment can substantially improve the quality of wood materials. Temperature is the most important factor during heat treatment affecting the properties of boards, so optimizing the treatment process should include careful investigation of thermal transfer phenomena. In this work, the transient heat transfer characteristics during the heat treatment of wood at 120 °C, 150 °C, and 180 °C were numerically studied per the temperature distribution and variation in sample boards. The heat transfer model was established by comparative analysis of the experimental data and simulation data. ANSYS software was used to simulate heat transfer during the process of wood heat treatment; simulation results were consistent with experimental results at average relative error within 5%. This accurate simulation of heat transfer within wood samples provides useful insight into the heat transfer mechanisms. [ABSTRACT FROM AUTHOR]

Modification in thermal transfer mechanisms induced by light in human lung epithelial cancer cells was experimentally controlled by chaotic attractors dependent on optical transmittance. The evolution of a chaotic modulation driven by optical signals in our system was studied in the cells integrated in monolayer form. The identification of the photodamage in the studied samples was achieved by a straightforward measurement of transmitted light modulated by the Chen equations. The laser irradiation was triggered by a chaotic circuit monitoring the samples by optical imaging. Comparative experiments conducted by nanosecond pulses at 532 nm wavelength in single-shot mode revealed how the multi-photonic processes in the samples play a crucial role in the resulting photothermal phenomena. Fractional thermal transport was analyzed in order to describe the photoinduced energy transfer over the samples. The aim of the research is to highlight fractional models with immediate advantages for developing high precision phototechnology and photothermally-controlled ablation in biological systems. [Display omitted] • Controlled ablation in human lung epithelial cancer cells is presented. • Evolution of fractional photodamage with optical nonlinearities is analyzed. • Chaotic modulation in high-sensitive optical sensing is proposed. • Anisotropic thermal transfer induced by nanosecond pulses is discussed. [ABSTRACT FROM AUTHOR]

Self-propagating exothermic reaction (SPER) of alternating metal nanolayers provides intense localised heat that allows bonding of metals or alloys under ambient temperature. However, the formation of the bonds through the rapid heating and cooling confined at the bonding interfaces is a non-equilibrium process, and the thermal effect on solidification and manufacturing reliability is yet to be understood. In this work, the Cu/Sn-nanofoil-Sn/Cu interconnects (where Sn is a solder layer) prepared via SPER of Ni/Al nanofoil are studied by numerical simulations and experiments to understand the thermal transfer and its effect on the solidification. It has been found that the SPER completes within a few milliseconds, the temperature at solder/Cu interface can be higher than the melting point of solder, and the cooling rate can be as high as 1.5 × 107 °C/s, the maximum temperature gradient can reach 5.40 × 107 °C/m. The microstructure predicted by simulation agrees well to the experimental results: the columnar dendrites are formed in the solder during the cooling stage, and the columnar structures prefer to form and grow in the solder region due to the high cooling rate. • Combined macro thermal transfer simulation with phase field modelling • Predicted thermal affects during self-propagating exothermic reaction bonding • Simulated solidification of solder under rapid cooling rate • Simulated temperature and columnar grains agree well with the experiment. [ABSTRACT FROM AUTHOR]

A museum sample of perthitic feldspar was used to study the production of post-IR IRSL signals. It was found that traps responsible for low temperature (∼230 °C) TL peaks play an unexpectedly important role in post-IR IRSL production. During the production of the IRSL signal during low temperature IR stimulation (100 °C), electrons are optically transferred from IRSL traps into these TL traps which have been emptied by the preceding preheat at 320 °C. Subsequent heating to 300 °C causes thermal transfer of these electrons from these traps back into previously emptied IRSL traps which are related to the high temperature TL peaks. IR stimulation of these electrons results in post-IR IRSL. Thus the initial source of the post-IR IRSL signal is the same as the IRSL signal, with a role being played by intermediate traps that give rise to TL signals between 200 and 250 °C, and the final source is similar to that of the IRSL signal. Therefore the post-IR IRSL signal is a by-product of the production of the IRSL signal. It was also found that post-IR IRSL production with high post-IR IR stimulation temperatures (e.g. >230 °C) additionally includes a small contribution from the post-IR isothermal decay of high temperature TL peaks that are not sensitive to IR stimulation at low stimulation temperatures. [ABSTRACT FROM AUTHOR]

In this work, the asphalt mixture was prepared by partially replacing limestone with steel slag, and the self-healing properties under microwave heating (MH) were studied. Firstly, the element compositions of steel slag and its absorbing heating mechanism were analyzed. Then, five groups of semicircular bending (SCB) samples with different steel slag content were prepared, and the self-healing performance of the steel slag asphalt mixture was evaluated by the crack-healing test. Subsequently, the surface temperature and thermal transfer process of MH 40 s in SCB and crack propagation zone (CPZ) were compared and analyzed. Finally, the Marshall sample before and after MH were scanned by X-ray computed tomography (CT). The results show that steel slag has good wave absorption performance because it contains a lot of metal oxides. The initial strength of steel slag asphalt mixture does not decrease significantly, but its self-healing index fracture energy healing rate (FEHR) is obviously higher than that of the conventional mixture. And the self-healing properties of samples with higher steel slag content will be better. Besides, compared with the total average temperature of SCB, the FEHR of the sample is more correlated with the surface temperature of CPZ after MH. Based on CT scanning, steel slag is uniformly distributed in the mixture. An appropriate MH cycle can effectively improve the voids microstructural of the mixture, but an excessive MH cycle can bring negative effects. [ABSTRACT FROM AUTHOR]

Abstract: This work focuses on the modelling of thermal processes inside a planar high temperature steam electrolyzer that use cermets as electrodes. While the continuity equation for mass and charge have been demonstrated in a previous publication, energy balance for thermal transfers inside the electrode assembly is established via a control volume method. A non-dimensional number is built from different criterion used in the literature in order to validate the local thermal equilibrium assumption (LTE) inside the porous electrodes. A parametric analysis is carried out on a proton-conducting solid oxide electrolysis cell in galvanostatic mode. The results show that the heat sources are mainly ohmic and that their locations are not dependent on inlet current and inlet velocity of gases. This observation allows us to build an original thermal resistance network in order to analytically evaluate the temperature inside each component of the cell. This modelling strategy reduces computation time, allows reverse physical analysis and gives a precise estimation on the maximum temperatures attained in the components of the cells. [Copyright &y& Elsevier]

Abstract: The recently developed post-IR IRSL SAR protocol is promising to isolate more stable IRSL signals of feldspars. However, the high temperature thermal treatments used will inevitably induce thermally transferred post-IR IRSL295 (TT-post-IR IRSL295) signal, which would contribute to the measured post-IR IRSL295 signal of the test dose and may lead to inaccurate sensitivity correction. In this study, the effects of TT-post-IR IRSL295 signal in the post-IR IRSL295 SAR protocol are investigated using medium polyminerals from a loess section at Caoxian, northwestern Loess Plateau in China. The sensitivity changes of the IRSL50 and the post-IR IRSL295 signals are different from natural cycle to regenerative cycles, which can be attributed to the interference of the TT-post-IR IRSL295 signal. Such difference is dependent on the test dose and the post-IR IR stimulation time. The TT-post-IR IRSL295 signal is also shown to affect the post-IR IRSL295 D o and D e values and to cause overestimation of the fading rates. Our study therefore highlights the need of serious consideration on the effects of TT-post-IR IRSL signal when the post-IR IRSL SAR protocol is employed for dating. [Copyright &y& Elsevier]

Abstract: A three-dimensional atmospheric radiative model which evaluates the thermal-radiative transfers in the lower atmosphere was implemented in the atmospheric module of a Computational Fluid Dynamics code. This model can study the thermal effects of buildings on the local atmospheric flow with a coupled dynamic-radiative model. Previously, we have validated this approach and discussed the impact of the convective flux on the surface temperatures by comparing a detailed wind and temperature field with the Mock Urban Setting Test (MUST) experiment dataset. In this paper our objective is to demonstrate the ability of our radiative model to simulate the thermal effect of buildings on the local atmospheric flow under low wind speed condition. Therefore, we present different numerical simulations for low wind speed and higher building density than in MUST, comparing the neutral case with different levels of thermal exchange model and analyzing the differences. The results show first that taking into account the thermal stratification has a significant influence on the wind field. Then we show that the difference between the case for which we impose the temperatures and the case with temperatures calculated with a 3D radiative transfer scheme can also be important near the buildings. In addition, with the 3D radiative model, the temperature and vertical motion show an important sensitivity to changes in the physical parameters of the wall surfaces, such as the surface albedo. [Copyright &y& Elsevier]

Abstract: When using a single-aliquot regenerative dose (SAR) protocol for luminescence dating of sedimentary quartz grains, the fundamental assumption is that the sensitivity of the optically stimulated luminescence (OSL) produced by the regenerative doses can be monitored by their following test dose OSL response. Using well-bleached coarse quartz grains, OSL production in a SAR protocol was studied in detail when dose response curves were constructed using both single and multiple aliquot regenerative dose procedures. During application of the SAR protocol, two preheats are applied, each ahead of an OSL measurement that is produced by the regenerative dose and test dose, respectively. It is shown that sensitivity changes caused by heating were well corrected for using the OSL response to the test dose. However, these preheats are shown to result in thermally stimulated OSL signals that contribute both to the OSL response from the regenerative doses used to construct the dose response curve and to the OSL response from the test dose used to monitor OSL sensitivity changes as the quartz grains are repeatedly measured. A simple test is proposed to identify the contribution of the latter signal. [Copyright &y& Elsevier]

Abstract: During metal cutting processes, intensive friction and high temperature generated at the tool chip interface affect the cutting zone of the tool, by inducing damage and wear. To improve the cutting tool''s life, thin hard coatings, synthesized by physical or chemical vapor deposition (PVD or CVD) techniques, are often used as protective layers. In this work, numerical/theoretical analysis of dry machining has been performed to study the impact of different coating layers on the machining process. Four cases are considered: an uncoated tool made of tungsten carbide (WC–Co) and coated tungsten carbides in three different configurations. The first one is made of one layer namely TiN, the second one (hypothetical carbide insert) is composed of two layers (Al2O3 and TiN), and the last one has three layers (TiCN, Al2O3 and TiN). The workpiece material is an AISI 316L stainless steel. All cutting conditions are fixed in order to highlight the effect of coatings independently from others influencing parameters. The analysis has shown the impact of the different configurations of coatings on the temperature level inside the tool and on its surface, on the pressure and also on the cutting and feed forces. [Copyright &y& Elsevier]

Abstract: We have developed a method that allows biological tissues to be adhered together with minimal invasion by delivering integrated low-level energies from heat, pressure, and vibration. Tensile tests on adhered slices of porcine aorta were performed to determine the relationships between adhesive strength and conditions such as adhesion temperature, time, pressure, and vibration. The maximal adhesive shear tensile strength using the proposed method was 0.2MPa, which is half the strength of the porcine aorta and stronger than surgical tissue adhesive. Adhesion strength increased in proportion to temperature, time, and pressure, and also in the presence of vibration, indicating that vibrational energy contributes to the adhesive mechanism and strength. Adhesive stability, the effect of heat on adhesive strength, and the ability of tissue to adhere to artificial materials were also clarified. [Copyright &y& Elsevier]

Abstract: We investigate the use of quartz optically stimulated luminescence (OSL) dating for determining fluvial overbank sedimentation rates over decades to centuries. For the study we took 11 samples from three cores from an embanked floodplain along the River Waal (Rhine) near Neerijnen (The Netherlands). We propose a measurement protocol for young fluvial quartz based on the single-aliquot regenerative dose procedure. Parameters for the protocol are chosen to isolate the fast OSL component, eliminate an ultrafast OSL component and avoid thermal transfer. The protocol shows excellent dose recovery and recycling ratios. For each sample, a Gaussian is fitted to the lower part of the equivalent dose distribution to obtain an estimate of the burial dose. We discuss the validity of the OSL ages using internal and external controls, and conclude that there is no evidence for large systematic offsets in the OSL ages. OSL based sedimentation rates are between ∼3 and 8mm/a, in line with previous estimates. [Copyright &y& Elsevier]

Abstract: The geological record preserved in coastal salt marshes provides an opportunity to determine past hurricane activity during the Late Holocene in New England, USA. High precision dating is important to correlate overwash sand layers associated with hurricane strikes between different sites along the coastline. Three different optical dating methods have been tested and compared with independent age control; i) optically stimulated luminescence from quartz, ii) infrared stimulated luminescence from K-feldspar, and iii) a subtraction method. Quartz and K-feldspar dating results for three samples in a core from Round Hill Beach Marsh are in stratigraphic order and they are consistent within errors with radiocarbon ages and with each other. Subtraction dating results agreed with the quartz and K-feldspar ages for two of the three samples, but the subtraction age of the youngest sample gave an age underestimate. Replicate equivalent dose values from quartz showed a larger variation than those from feldspars, and this resulted in larger errors for the quartz and subtraction ages than those based on feldspars. K-feldspar yields the most precise optical ages, but is complicated by the need to correct for anomalous fading. Both quartz and K-feldspar are suitable for optical dating of hurricane overwash deposits in New England. [Copyright &y& Elsevier]

Abstract: Isothermal heating experiments on enamel fragments show that there are two pronounced increases in the intensity of the orientated CO2 − radicals, after heating for 15min at 225°C and 1440min at 175°C. While the powder spectra virtually remained unchanged at these heating steps, it was found that the angular intensity variability in the fragments greatly increased. In general, it is not possible to explain these increases by transfers from non-orientated CO2 − radicals to orientated, because there are simply not enough non-orientated CO2 − radicals in the unheated sample. Instead we attribute the increased angular intensity variability by a higher crystallinity in certain domains in the enamel. It was found that after heating for 15min at 225°C, newly occurring orientated CO2 − radicals had a somewhat different orientation to the unheated. [Copyright &y& Elsevier]

[Display omitted] • Light absorbing conical aerogel with vertically aligned channels was constructed. • Simultaneous efficient passive cooling and solar energy utilization was achieved. • The conical aerogel exhibited excellent thermal transfer capability. • Cooling power reached 271.56 W m−2 and evaporation rate was 2.23 kg m-2h−1. • The outdoor experiment demonstrated the great potential for practical applications. Passive cooling technology is zero-energy and eco-friendly, and has the potential to reduce reliance on energy-intensive cooling techniques such as compression refrigeration. Typically, in order to achieve efficient cooling, the passive system should reflect sunlight as much as possible to minimise the input energy. Here, we demonstrate an unconventional passive cooling process in a system with high light absorption of approximately 99.3%. The main component of the system is an aerogel with a unique conical structure that performs thermal transfer. Solar-thermal and ambient thermal energy are utilized to power the vaporization of water contained in the directional channel of the aerogel, where water keeps in capillary state. Under a simulated condition of one sun irradiation, the average evaporation rate of the conical aerogel is as high as 2.23 kg m-2h−1, and the maximum specific cooling power is 271.56 W m−2. An outdoor prototype demonstrates that the temperature of the cooling room can be up to 13.7 °C lower than that of ambient air on a sunny day of summer. This simultaneous solar steam generation and passive cooling system has great application potential in thermal concentration and environmental cooling processes. [ABSTRACT FROM AUTHOR]

In this study, a fully coupled analytical model is developed for thermal energy transfer in a single fracture-rock matrix system where the coupling implies that the governing equations of thermal transfer in the fracture and rock matrix are supplemented with the continuity conditions of temperature and thermal flux at the interfaces of the fracture-rock matrix. The proposed model accounts for thermal convection, longitudinal thermal conduction and thermal dispersion in the fracture, and transverse thermal conduction in the rock matrix. The fully coupled two-dimensional model is established to investigate the thermal energy transfer processes, assess the spatiotemporal temperature distribution in the fracture and rock matrix system and investigate the role of the rock matrix. The solutions are verified with the existing studies and proven to be accurate and robust. The present study demonstrates that: 1) thermal dispersion in the fracture plays an important role in the temperature distribution in the fracture and rock matrix domains, and longitudinal thermal conduction in the fracture has minor effects on the temperature distribution in the system; 2) transverse thermal conduction in the rock matrix is a critical parameter that determines the spatiotemporal temperature distribution in both the fracture and the rock matrix domains. Ignoring thermal conduction in the rock matrix will lead to a significant overestimation of temperature in the short and long terms; 3) the sensitivity analysis implies that thermal energy transfer in the system is sensitive to the fluid velocity in the fracture, thermal dispersivity in the fracture and thermal conductivity in the rock matrix, and less sensitive to thermal conductivity in the fracture. • A model for heat transfer in the fracture-rock matrix system is proposed with thermal convection, conduction and dispersion • Thermal dispersion in the fracture is important to the temperature distribution in the system • Transverse thermal conduction in the rock matrix is a critical parameter for heat transfer in the fracture [ABSTRACT FROM AUTHOR]

Abstract: A next-generation drilling system, equipped with a thermal drilling device, is proposed for glacier ice. The system is designed to penetrate glacier ice via melting of the ice and continuously analyze melt-water in a contamination-free sonde. This new type of drilling system is expected to provide analysis data in less time and at less cost than existing systems. Because of the limited number of parameters that can be measured, the proposed system will not take the place of conventional drilling systems that are used to obtain ice cores; however, it will provide a useful method for quickly and simply investigating glacier ice. An electro-thermal drilling device is one of the most important elements needed to develop the proposed system. To estimate the thermal supply required to reach a target depth in a reasonable time, laboratory experiments were conducted using ice blocks and a small sonde equipped solely with heaters. Thermal calculations were then performed under a limited range of conditions. The experiments were undertaken to investigate the effects of the shape and material of the drill head and heater temperature on the rate of penetration into the ice. Additional thermal calculations were then performed based on the experimental results. According to the simple thermal calculations, if the thermal loss that occurs while heat is transferred from the heater to ice (in melting the ice) is assumed to be 50%, the total thermal supply required for heaters in the sonde and cable is as follows: (i) 4.8kW (sonde) plus 0W (cable) to penetrate to 300m depth over 10days into temperate glacier ice for which the temperature is 0°C at all depths and to maintain a water layer along 300m of cable; (ii) 10kW (sonde) plus 19–32kW (cable) to penetrate to 1000m depth over 1month into cold glacier ice for which the temperature is −25°C at the surface and 0°C at 1000m depth and to maintain a water layer along 1000m of cable; and (iii) 19kW (sonde) plus 140–235kW (cable) to penetrate to 3000m depth over 2months into an ice sheet for which the temperature is −55°C at the surface and 0°C at 3000m depth and to maintain a water layer along 3000m of cable. The thermal supply required for the cable is strongly affected by the thickness of the water layer, cable diameter, and the horizontal distance from the ice wall at which the ice temperature was maintained at its initial temperature. A large thermal supply is required to heat 3000m of cable in an ice sheet (scenario (iii) above), but penetration into glacier ice (scenarios (i) and (ii) above) could be realistic with the use of a currently employed generator. [Copyright &y& Elsevier]

Abstract: Natural CaF2 is very well known thermoluminescent (TL) material, since it has been extensively used as a dosimeter. Its basic advantage is the exhibited high TL sensitivity. In the present work, the optically stimulated luminescence (OSL) sensitivity of this material was studied by exposing it to environmental radiation for time intervals of few hours up to a few days, and was found to be very high. By analyzing the TL glow curves and the OSL decay curves into their individual glow-peaks and components respectively, a relation between specific glow-peaks and OSL components was established. An intense thermal transfer effect occurring during optical stimulation at high temperature was observed and an explanation is offered according to existing models. [Copyright &y& Elsevier]

Abstract: Overestimation of equivalent dose () values due to thermal transfer was observed for quartz when using the single-aliquot regenerative-dose protocol (SAR) to recover a small known dose (1.74Gy) given after an optical bleach. Both the fast and medium components resulted in overestimation, with the effect being larger for the medium component and the effect could be seen in plot as stimulation time increased. The dose-generated OSL signal can be distinguished from the thermally transferred signal based on the linear relationship between the initial and final parts of the thermally transferred OSL curves. A method is proposed to correct for thermal-transfer effects using the OSL signals measured in repeated heat/OSL cycles incorporated into the SAR protocol. This approach was applied to artificially irradiated and optically bleached samples, and it was found that the thermal-transfer effects can be removed when using only a single aliquot. In dose recovery tests, the known dose (1.74Gy) could be obtained using this approach and a value of was obtained for optically bleached aliquots. [Copyright &y& Elsevier]

Abstract: The thermal transfer optically stimulated luminescence (OSL) signals of bleached samples of sedimentary quartz are investigated using repeated heat/OSL measurement cycles with different heating temperatures ranging from 200 to . Under optical stimulation, the thermal transfer OSL decays with stimulation time. A strong correlation is observed between the initial part and the final part of the OSL decay curves. This relationship is dependent on the heating conditions and thermal history of the sample. Our results suggest that the thermal transfer OSL is due to the retrapping of charges that originated from optically insensitive traps by thermal release during heating, and not from the slowly bleached component associated with bleachable traps. Two kinds of OSL traps are involved into the thermal transfer, one is corresponding to the TL peak and the other is related to more stable traps. The thermally transferred signals can be distinguished from dose-generated signals by making repeated measurements of thermally transferred OSL decay curves. [Copyright &y& Elsevier]

Abstract: This experimental investigation is structured to describe the thermal behaviour of a polyester+TGIC powder coating during infrared curing. The study hence correlates thermal modelling of the cure process and kinetics studies. First, the curing kinetics is determined using DSC experiments and modelling with the software Matlab. The results from this study are then used to study the infrared curing efficiency. Medium wave infrared leads to the fastest cure. Moreover, coupling the thermal modelling of the cure process and the kinetics has enabled us to develop a model predicting the evolution of the temperature and the degree of conversion, using the hypothesis that the paint film and the substrate are at the same temperature. [Copyright &y& Elsevier]

We study the effect of viscosity on the thermal transfer at the interface associated with a spherical liquid droplet impulsively started at constant velocity in another liquid of large extent at rest. Exact solutions for the thermal distributions are derived at short moving time. From algebraic and numerical considerations we show that viscous effects on the thermal transfer at the interface are negligible by comparison with the inviscid solutions. On the contrary, they predominantly occur on both side of it, in the two adjacent boundary layers, with a spreading effect with time. [Copyright &y& Elsevier]

The systematic study of optical absorption and laser-induced heating of dielectric microcapsules with water filling and light absorbing polymer shell simulating transport cargo microcontainers is presented. By means of FDTD and FEM techniques, the numerical calculations of optical field spatial distribution inside and near the microcapsules are carried out, and the temporal dynamics of temperature profiles of core-shell microparticles of various morphological types (spheres, ellipsoids, boxes, cubes, cylinders) and microcapsule clusters in different configurations is addressed. The spatial configurations of light absorption regions are shown to be substantially dependent on the morphology of the microcapsules. For isolated microcapsules, the most efficient laser heating is realized in capsules of cubic and cylindrical shapes. When the capsules are aggregated into the densely packed cluster, the characteristic heating depth of the whole assembly is higher for cylindrical microcapsules. In sparse microassemblies the square-shaped capsules are preferable for increasing the efficiency of laser heating. [ABSTRACT FROM AUTHOR]

This paper presents the mathematical modeling and numerical simulations of turbulent flows with thermal convection. Cartesian numerical meshes are used for non-Cartesian problems thanks to the dynamic and thermal immersed boundary methods. Turbulence modeling was performed using the LES (Large Eddy Simulation) methodology with dynamic Smagorinsky subgrid-scale modeling. All of the simulations were carried out using a computational code that was developed at home (MFSim - Multiphysic Simulator). Two kinds of thermal immersed boundary conditions were proposed, implemented, and validated. To exemplify the functionalities of this computational tool, simulations of turbulent natural convection were performed on a horizontal cylinder. Consistent qualitative results were obtained, which reveal the dynamic structures characterizing the transition to turbulence. The corresponding statistical results compare well with the reference results that have been published by other authors. • Modeling of multi-physical solutions through multi-methods. • Block-structured cartesian adaptive mesh to models the flow. • Immersed boundary method dynamic and thermal to model complex geometries. • Turbulence closure model to model the turbulent thermal transfer. • Implementation of two type of boundary conditions for the thermal immersed boundary. [ABSTRACT FROM AUTHOR]