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Obtaining non-contact optical temperature sensing materials with good thermal stability and luminescent properties is one of the current research hotspots. In this work, Er3+/Yb3+ co doped CaGdAlO4:Erx,Yb0.10 (x = 0.006, 0.008, 0.010, 0.012, 0.014) single-phase phosphors were prepared by high-temperature solid-state method. For CaGdAlO4 : Erx, Yb0.10 powders with different Er3+ doping concentrations, the particle sizes range from 0.6 μm to 4.2 μm. When the samples are under 980 nm laser excitation, there exists two emission bands in the 500 * 575 nm range and one emission band in the 630 * 690 nm. The two stronger green emission bands located at 528 and 550 nm, and they could be attributed to ² H11/2→4 I15/2 and 4S3/2 →4 I15/2 transitions, while the weaker red emission band at 663 nm could be attributed to 4F9/2 →4 I15/2 transition of Er3+. The optimal upconversion luminescence intensity was obtained from CaGdAlO4 :Er0.010,Yb0.0. In the temperature range of 300 * 573 K, based on fluorescence intensity ratio FIR528/550 parameters, the absolute sensitivity SA increases from 44.4 x10-4 K-1 (@300 K) to 52.0 x 10-4 K-1 (@ 445 K), and then decreases to 49.0 x 10-4 K-1 (@ 573 K). The relative sensitivity SR decreases monotonically from 0.95 x 10-2 K-1 (@ 300 K) to 0.27 x 10-2 K-1 (@ 573 K). Furthermore, the heating-cooling cycling experiment shows that the thermal repeatability of temperature sensing for the phosphor is better than 98%. The results demonstrate that CaGdAlO4 :Er0. 010, Yb0.10 phosphors have potential applications in the field of optical temperature sensing. [ABSTRACT FROM AUTHOR]

Thermal safety issues of batteries have hindered their large‐scale applications. Nonflammable electrolytes improved safety but solvent evaporation above 100 °C limited thermal tolerance, lacking reliability. Herein, fire‐tolerant metal‐air batteries were realized by introducing solute‐in‐air electrolytes whose hygroscopic solutes could spontaneously reabsorb the evaporated water solvent. Using Zn/CaCl2‐in‐air/carbon batteries as a proof‐of‐concept, they failed upon burning at 631.8 °C but self‐recovered then by reabsorbing water from the air at room temperature. Different from conventional aqueous electrolytes whose irreversible thermal transformation is determined by the boiling points of solvents, solute‐in‐air electrolytes make this transformation determined by the much higher decomposition temperature of solutes. It was found that stronger intramolecular bonds instead of intermolecular (van der Waals) interactions were strongly correlated to ultra‐high tolerance temperatures of our solute‐in‐air electrolytes, inspiring a concept of non‐van der Waals electrolytes. Our study would improve the understanding of the thermal properties of electrolytes, guide the design of solute‐in‐air electrolytes, and enhance battery safety. [ABSTRACT FROM AUTHOR]

Thermal safety issues of batteries have hindered their large‐scale applications. Nonflammable electrolytes improved safety but solvent evaporation above 100 °C limited thermal tolerance, lacking reliability. Herein, fire‐tolerant metal‐air batteries were realized by introducing solute‐in‐air electrolytes whose hygroscopic solutes could spontaneously reabsorb the evaporated water solvent. Using Zn/CaCl2‐in‐air/carbon batteries as a proof‐of‐concept, they failed upon burning at 631.8 °C but self‐recovered then by reabsorbing water from the air at room temperature. Different from conventional aqueous electrolytes whose irreversible thermal transformation is determined by the boiling points of solvents, solute‐in‐air electrolytes make this transformation determined by the much higher decomposition temperature of solutes. It was found that stronger intramolecular bonds instead of intermolecular (van der Waals) interactions were strongly correlated to ultra‐high tolerance temperatures of our solute‐in‐air electrolytes, inspiring a concept of non‐van der Waals electrolytes. Our study would improve the understanding of the thermal properties of electrolytes, guide the design of solute‐in‐air electrolytes, and enhance battery safety. [ABSTRACT FROM AUTHOR]

Sample holders for transmission electron microscopy (TEM) based on micro‐electro‐mechanical systems (MEMS) have recently become popular for investigating the behavior of nanomaterials under in situ or environmental conditions. The accuracy and reproducibility of these in situ holders are essential to ensure the reliability of experimental results. In addition, the uniformity of an applied temperature trigger across the MEMS chip is a crucial parameter. In this work, it is measured the temperature homogeneity of MEMS‐based heating sample supports by locally analyzing the dynamics of heat‐induced alloying of Au@Ag nanoparticles located in different regions of the support through quantitative fast high‐angle annular dark‐field scanning TEM tomography. These results demonstrate the superior temperature homogeneity of a microheater design based on a heating element shaped as a circular spiral with a width decreasing outwards compared to a double spiral‐shaped designed microheater. The proposed approach to measure the local temperature homogeneity based on the thermal properties of bimetallic nanoparticles will support the future development of MEMS‐based heating supports with improved thermal properties and in situ studies where high precision in the temperature at a certain position is required. [ABSTRACT FROM AUTHOR]

Entropy plays a crucial role in designing new functional materials or enhancing material performance. The design of high entropy ceramics (HECs) introduces a larger composition space, thus the understanding of the correlation between the composition, entropy effect, and the performance of HECs is becoming increasingly important. In this work, to pursue superior properties, a series of CeNbO 4 -based solid solution ceramics with a maximum of 9 species cations in a single sublattice were synthesized by using high entropy configuration strategy. The interaction of composition, size disorder, and configurational entropy on the properties of HECs was emphasized. The potential conflict between high resistivity and low material constant of thermosensitive ceramics was overcome and thus achieving excellent thermal sensitivity properties having an extremely wide temperature range from room temperature to 1623 K and long-term high-temperature stability. This will bring innovative prospects for the design and application of high-temperature functional ceramics. [ABSTRACT FROM AUTHOR]

Gear transmission errors are influenced by temperature especially in the aerospace field. A model is proposed to investigate the influence of temperature on cylindrical gear transmission errors based on the thermal network (TETN). The gear temperature field distribution model is established based on the thermal network method, and gear thermal deformation can be calculated along the gear meshing line. Regarding the gear single-flank rolling process, the variation of gear transmission errors under temperature is determined. In numerical calculations in MATLAB, the variation of gear transmission errors at 100 ℃ compared to 20 ℃ is -4.20 μm, which decreases almost linearly while the thermal expansion coefficient of the gear material increases. The simulation of the gear transmission errors variation of temperatures using the finite element method (FEM) were carried out in Workbench software under Ansys and the average difference of the TETN model results between calculations and FEM for different temperatures was 0.24 μm. Experiments were carried out on the gear tester in temperatures ranging from 0℃ to 100℃, the TETN model results in calculations were compared with the results of the tester, and the average difference was -1.15 μm. The results show that the proposed TETN can be used as an algorithm to determine the variation of gear transmission errors under the influence of temperature. [ABSTRACT FROM AUTHOR]

The effect of thermal prehistory and mechanical field on the morphology and physicomechanical and thermal properties of poly(vinyl alcohol) cryogels has been studied. Using the methods of rheometry, DSC, and X-day diffraction analysis it is revealed that an increase in the heat treatment temperature of cryogels causes a rise of the melting temperature and a change in the crystallinity of PVA cryogels, as is typical for the annealing phenomenon. It is established that the annealing of PVA cryogels formed under repeated freezing with simultaneous forced compression contributes to the formation of cryogels with the spatial network being stable up to the onset of solvent boiling. [ABSTRACT FROM AUTHOR]

Carbon-metal carbide composites are a novel family of materials with potential application in heat dissipation due to the lightness and thermal-mechanical properties. Within these composites, those of graphite-chromium carbide have been still few studied. Therefore, this research focuses on both the influence of the powder preparation method (mechanical mixing (MM) and colloidal synthesis (CS)) and the spark plasma sintering (SPS) temperature (1600, 1700, 1800, 1900 and 2000 °C) in the properties of the composite graphite-7 vol. Cr. Results indicate that the composites sintered from powders processed by CS exhibit better properties, which can be explained by the better dispersion of the chromium carbide, formed during the sintering process, in the matrix of composite. Apart from the powder preparation method, sintering temperature has influence on the properties of the composite: 1900 °C is the best in the case of the route CS + SPS, while 2000 °C is the best option in the route MM + SPS. The thermal conductivity in-plane is 1.75 times greater in the CS than in the MM route, which suggests a better performance in the composite processed by colloidal route in heat dissipation applications. [ABSTRACT FROM AUTHOR]

Pultrusion is a high-volume manufacturing process for Fibre-Reinforced Polymer (FRP) composites. It requires careful tuning and optimisation of process parameters to obtain the maximum production rate. The present work focuses on the correlation between the set die temperatures of 80 °C, 100 °C, 120 °C, and 140 °C and the resin cure state at constant pull speeds. Lab-scale oven trials were conducted to understand the thermal behaviour of the resin system and to provide a temperature range for the pultrusion trials. Dielectric Analysis (DEA) was used during pultrusion trials to monitor the effect of die temperature on the cure progression. The DEA results showed that, by increasing die temperature, the exothermic peak shifts closer towards the die entry. Moreover, the degree of cure for samples processed at 140 °C was 97.7%, in comparison to 86.2% for those cured at 100 °C. The rate of conversion and the degree of cure correspond directly to the set die temperatures of the pultrusion trials, contributing to understanding the effect of die temperature on cure progression. Mechanical and thermal material properties were measured. Samples cured at 120 °C showed the highest mechanical performance, exceeding those cured at 140 °C, linked to the generation of higher internal stress due to the higher rate of conversion. This work can be used as a guide for pultruded composite sections, to understand the cure behaviour of resin systems under various applied temperatures and the impact of the die temperature conditions on thermal and mechanical properties. [ABSTRACT FROM AUTHOR]

With the discovery of research, many properties of carbon dots are getting better and better. People have taken advantage of this and utilized them interspersed in various fields. In the present study, water-soluble nitrogen-doped carbon dots (N-CDs) with excellent optical and fluorescence thermal properties were prepared by the hydrothermal method using 4-dimethylaminopyridine and N,N′-methylenebisacrylamide as precursors. Co2+ has a selective bursting effect on the fluorescence of N-CDs. The fluorescence of N-CDs is selectively burst by Co2+, and the high sensitivity is good in the range of 0–12 μM with a detection limit of 74 nM. In addition, the good temperature response (reversible and recoverable fluorescence in the temperature range of 20~90 °C) and excellent optical properties of the N-CDs also make them new potentials in the field of fluorescent inks and temperature sensing. [ABSTRACT FROM AUTHOR]

In this study, the effect of fiber orientation on the temperature history during the layup process is comprehensively investigated experimentally and numerically. Specimens with three different fiber orientations (i.e. [0°/0°/0°], [0°/45°/0°], and [0°/90°/0°]) are manufactured at two layup speeds and characterized for determining the degree of intimate contact and then calculating the thermal contact resistance. Then, an improved thermal model with thermal contact resistance is developed and validated to predict the temperature history accurately. The experimental results indicate that the degree of intimate contact decreases by increasing the difference in fiber orientation between the interfaces of successive plies, revealing a relationship between substrate fiber orientations and cooling rates. The effect of cooling rate on the degree of crystallinity is studied for all stacking configurations at two layup speeds and found that as the angle between the subsequent plies decreases, the cooling increases, leading to a drop in the degree of crystallinity. The outcomes of this study address the need for an improved thermal model approach for accurately predicting the thermal history of the manufactured composite by the laser-assisted fiber placement process. [ABSTRACT FROM AUTHOR]

In the recent years, additive manufacturing (AM) has been widely expanded for manufacturing the polymer and polymer-based composite parts. The main drawback of the material extrusion additive manufactured parts is the weaker mechanical properties in comparison to the manufactured parts by the conventional methods. The stated weak mechanical properties are due to the weak adhesion between the deposited layers. The poor adhesion between the deposited layers in material extrusion additive manufacturing process is due to the fact that the previous deposited filament (n-1) is already cooled and solidified. To ensure the appropriate adhesion between the two adjacent filaments, the temperature of the first deposited layer (n-1) has to be high enough to obtain a suitable adhesion to the subsequent layer (n) but in an optimum range to avoid the lack of the dimensional accuracy. Therefore, a precise and local measurement of the temperature on the scale of the diameter of the filaments is necessary. In this study, four important process parameters (liquefier temperature, layer height, print speed, and bed platform temperature) were selected to study their effects on the rheological behavior and temperature evolution of the PA6 and CF-PA6 materials during material extrusion process. Then, the impact of the short/chopped reinforcement on the thermal and mechanical properties of the material extrusion additive manufacturing processed polymer-based composites were studied by comparing the obtained results from PA6 and CF-PA6 parts. In one experiment, it was observed that increasing the liquefier temperature from 220 to 240 °C increased the tensile strength and crystallinity percentage of the manufactured PA6 and CF-PA6 specimens. It was determined that the crystallinity percentages of PA6 and CF-PA6 specimens increased from 12.51 to 14.40% and from 19.97 to 20.51%, respectively. One of the existence effects of carbon fibers is highlighted in the higher crystallinity values of the CF-PA6 specimens comparing PA6 specimens. Finally, a time–temperature-transformation diagram was plotted to determine the processability condition of the utilized materials. It can be helpful for the designers and researchers to find out the optimal material extrusion additive manufacturing process parameters condition for the utilized raw materials. [ABSTRACT FROM AUTHOR]

Glacier surfaces are highly heterogeneous mixtures of ice, snow, light-absorbing impurities and debris material. The spatial and temporal variability of these components affects ice surface characteristics and strongly influences glacier energy and mass balance. Remote sensing offers a unique opportunity to characterize glacier optical and thermal properties, enabling a better understanding of different processes occurring at the glacial surface. In this study, we evaluate the potential of optical and thermal data collected from field and drone platforms to map the abundances of predominant glacier surfaces (i.e., snow, clean ice, melting ice, dark ice, cryoconite, dusty snow and debris cover) on the Zebrù glacier in the Italian Alps. The drone surveys were conducted on the ablation zone of the glacier on 29 and 30 July 2020, corresponding to the middle of the ablation season. We identified very high heterogeneity of surface types dominated by melting ice (30% of the investigated area), dark ice (24%), clean ice (19%) and debris cover (17%). The surface temperature of debris cover was inversely related to debris-cover thickness. This relation is influenced by the petrology of debris cover, suggesting the importance of lithology when considering the role of debris over glaciers. Multispectral and thermal drone surveys can thus provide accurate high-resolution maps of different snow and ice types and their temperature, which are critical elements to better understand the glacier's energy budget and melt rates. [ABSTRACT FROM AUTHOR]

Bi0.5Na0.5TiO3‐based ceramics with high remnant polarization Pr have shown outstanding potential in the application of high‐power ferroelectric transducers. However, low depolarization temperature Td is an obstacle for their application. Here, a composition design strategy was proposed to simultaneously improve the Td and Pr in BNT‐based materials. Ultrahigh Pr of 40.56 µC/cm2 and relative high Td of 184°C were synergistically achieved in (Bi0.5Na0.5)(Ti0.995Mn0.005)O3 (BNMT) ceramics by adding 1.0 mol% BiGaO3 (BG), which is superior to other reported lead‐free systems. The excellent ferroelectric properties were attributed to strengthen ferroelectric order as evidenced by increased rhombohedral distortion. Meanwhile, the enhanced depolarization temperature, increasing from 168°C for x = 0% to 184°C for x = 1.0%, can be ascribed to the suppression of the thermal‐induced ferroelectric‐relaxor phase transition by adding BG. Those results enable the BNMT‐BG systems ceramics to be an attractive candidate for application in high‐power supplies. [ABSTRACT FROM AUTHOR]

The role of the melting conditions and furnaces used to the obtained final colors has always been a question raised when investigating formulations and recipes of historical glasses. The focus of the present work is the reproduction of three recipes of red enamel glass of the manuscript by Neri, L'arte vetraria (1612) following the translation and comments by Kunckel's in Ars Vitraria Experimentalis (1679). The reproductions include the production of each individual compound of the selected recipes following instructions, and the final glass production in electric and wood‐fire furnaces to assess the effect of different melting conditions. A multianalytical approach was used to fully characterize the produced samples allowing the study of the enamel chemical composition, color, crystals formations, and thermal properties. The results indicate that no significant color differences may be attributed to the melting conditions. However, it revealed that the samples produced in the electric furnace at 1200°C present a high crystallinity degree and the formation of white crystals at room temperature in a short period of time. The formation of crystals on glass is critical, and historically, to avoid it, these recipes must have been made at temperatures between 1050 and 1100°C. [ABSTRACT FROM AUTHOR]

In this study, a novel temperature-sensitive material, Sr3Y2Ge3O12:Bi3+,Sm3+ phosphor, was successfully synthesized by a solid-state reaction method. Under 376 nm light excitation, the as-prepared phosphor presents both blue emissions of Bi3+ and orange red emissions of Sm3+ due to energy transfer from Bi3+ to Sm3+. Owing to the significant difference in thermal quenching properties and the distinguishable emission between Bi3+ and Sm3+ ions, the temperature sensing performance of the prepared phosphor was evaluated by measuring the fluorescence intensity ratio (FIR) of Sm3+versus Bi3+. More importantly, for the first time, it was found that the absolute and relative sensitivities of Sr3Y2Ge3O12:Bi3+,Sm3+ could be tuned by changing the concentration of activators to determine the optimal temperature measurement conditions, which opened up the possibility of improving the performance of fluorescence temperature sensing materials. [ABSTRACT FROM AUTHOR]

The development of geothermal resources in the Dongpu Depression can improve not only the economic benefits of the oilfield but also the ecological environment. Therefore, it is necessary to evaluate the geothermal resources in the region. Based on the heat flow, geothermal gradient and thermal properties, the temperatures and their distribution in different strata are calculated using geothermal methods, and the geothermal resource types of the Dongpu Depression are identified. The results show that the geothermal resources include low-temperature, medium-temperature and high-temperature geothermal resources in the Dongpu Depression. The Minghuazhen and Guantao Formations mainly include low-temperature and medium-temperature geothermal resources; the Dongying and Shahejie Formations include low-temperature, medium-temperature and high-temperature geothermal resources; the Ordovician rocks mainly include medium-temperature and high-temperature geothermal resources. The Minghuazhen, Guantao and Dongying Formations can form good geothermal reservoirs and are favorable layers for exploring low-temperature and medium-temperature geothermal resources. The geothermal reservoir of the Shahejie Formation is relatively poor, and the thermal reservoirs may be developed in the western slope zone and the central uplift. The Ordovician carbonate strata can provide thermal reservoirs for geothermal resources, and the Cenozoic bottom temperature is more than 150 °C except for most of the western gentle slope zone. In addition, for the same stratum, the geothermal temperatures in the southern Dongpu Depression are higher than those in the northern depression. [ABSTRACT FROM AUTHOR]

Newly developed wheelchair cushions, nowadays, promise to offer more comfort and protection against injury for wheelchair users. Therefore, developing novel wheelchair cushions has become a real challenge for manufacturers in recent years. In particular, thermal properties of the wheelchair cushion and their effect on the user's comfort are very important factors in the design and optimization. This paper reports the findings of an investigation into the thermal properties of wheelchair cushions using an infrared thermography system. The experimental results showed a variation in the temperature behavior of different trademarks of cushions depending on the heating zones and the C1 cushion made in TPU material has more advantages than the other cushions made in PU foam, pharmform, and visco-foam. The results and analysis from this research will help to find a better type of cushion and contribute to collecting useful medical information to prevent pressure ulcers for bedridden patients. [ABSTRACT FROM AUTHOR]

Toughening efficiency of poly(ethylene-n-butylene-acrylate-co-glycidyl methacrylate) (EBA-GMA) in poly(lactic acid) (PLA) matrix has been found to significantly increase at elevated blending temperature. In the case of PLA/EBA-GMA blends having 10.0 or 12.5 wt% EBA-GMA contents, the accelerated PLA degradation at raised processing temperature resulted in reduced mechanical performance. At 15.0 wt% EBA-GMA ratio, however, increased elongation and by 250% improved notched Izod impact strength was achieved when the blending temperature was raised from 240 to 260 °C. This beneficial effect is attributed to the accelerated compatibilization reactions between the components in the presence of shortchain PLA molecules, which allow the rapid formation of a toughening enhancer interphase (TEI) during melt processing. As a result, the brittle-ductile transition can be reached at lower elastomer content than expected. Decreased melt flow index (MFI) values besides stabilized blend morphology indicated efficient PLA--EBA-GMA compatibilization at elevated processing temperature. Accordingly, enhanced nucleation ability of the PLA/EBA-GMA interphase and hindered chain crystallization of PLA were found by differential scanning calorimetry (DSC) analyses. In association with the intensified compatibilization reactions cross-linking of the terpolymer was also revealed using the thermally stimulated depolarization current (TSDC) technique. [ABSTRACT FROM AUTHOR]

The effects of post-treatment temperature-based methods for accelerating the ageing of PLA were studied on 1D single-PLA filaments after fused filament fabrication (FFF). The goal was to answer the questions whether the PLA can be safely aged—i.e., without degrading—at higher temperatures; at which temperatures, if any; how long it takes for the PLA to fully age at the chosen temperature; and which are the main differences between the material aged at room temperature and the material aged at higher temperatures. We also share other helpful information found. The use of 1D filaments allows for decoupling the variables related to the 3D structure (layer height, raster angle, infill density, and layers adhesion) from the variables solely related to the material (here, we analysed the molecular weight, the molecular orientation, and the crystallinity). 1D PLA filaments were aged at 20, 39, 42, 51, 65, 75, and 80 °C in a water-bath-inspired process in which the hydrolytic degradation of the PLA was minimised for the ageing temperatures of interest. Those temperatures were selected based on a differential scanning calorimetry (DSC) scan of the PLA right after it was printed in order to study the most effective ageing temperature, 39 °C, and highlight possible degradation mechanisms during ageing. The evolution of the thermal and mechanical properties of the PLA filaments at different temperatures was recorded and compared with those of the material aged at room temperature. A DSC scan was used to evaluate the thermal and physical properties, in which the glass transition, enthalpic relaxation, crystallisation, and melting reactions were analysed. A double glass transition was found, and its potential implications for the scientific community are discussed. Tensile tests were performed to evaluate the tensile strength and elastic modulus. The flow-induced molecular orientation, the degradation, the logistic fitting, and the so-called summer effect—the stabilisation of properties at higher values when aged at higher temperatures—are discussed to assess the safety of accelerating the ageing rate and the differences between the materials aged at different temperatures. It was found that the PLA aged at 39 °C (1) reached almost stable properties with just one day of ageing, i.e., the ageing rate accelerated by 875% for the elastic modulus and by 1635% for the yield strength; (2) the stable properties were higher than those from the PLA aged at room temperature; and (3) no signs of degradation were identified for the ageing temperature of interest. [ABSTRACT FROM AUTHOR]

Animals breeding in nest‐boxes experience nesting environments in which they did not originally evolve. Despite the central importance of nesting microclimate for offspring fitness, little is known about the thermal properties of human‐provided nest sites compared to natural ones. In particular, comparisons with offspring in the nest are lacking. Here, we compare microclimate (temperature and absolute humidity) from the onset of breeding, thus starting with nest‐site choice and ending with the post‐fledging stage, quantified in natural cavities and nest‐boxes used by several species of hollow‐nesting birds in a temperate deciduous forest. We confirm that across all nesting stages, nest‐boxes were thermally unstable when compared to natural cavities, with higher temperature maximums, larger amplitudes and worse insulation from maximum ambient temperatures relative to natural cavities. Surprisingly, as average humidity of natural cavities was previously shown to be higher than in nest‐boxes, in the presence of actively thermoregulating young, nest‐boxes were more humid than natural cavities. When offspring were in the nest, internal microclimatic shifts were mitigated three times more effectively in natural cavities than in nest‐boxes (in terms of mean daily differences from ambient temperature). Artificial cavity microclimate is likely to amplify the adverse effects of projected temperature increases by compromising thermoregulation of developing animals. We stress that conservation efforts should focus on the protection of areas offering natural breeding‐hollows to reduce the potential impacts of climate change on breeding animals. [ABSTRACT FROM AUTHOR]

Phenotypic convergence across distantly related taxa can be driven by similar selective pressures from the environment or intrinsic constraints. The roles of these processes on physiological strategies, such as homeothermy, are poorly understood. We studied the evolution of thermal properties of mammalian pelage in a diverse community of rodents inhabiting the Mojave Desert, USA. We used a heat flux device to measure the thermal insulation of museum specimens and determined whether thermal properties were associated with habitat preferences while assessing phylogenetic dependence. Species that prefer arid habitats exhibited lower conductivity and thinner pelage relative to species with other habitat preferences. Despite being thinner, the pelage of arid species exhibited comparable insulation to the pelage of the other species due to its lower conductivity. Thus, arid species have insulative pelage while simultaneously benefitting from thin pelage that promotes convective cooling. We found no evidence of intrinsic constraints or phylogenetic dependence, indicating pelage readily evolves to environmental pressures. Thermoregulatory simulations demonstrated that arid specialists reduced energetic costs required for homeothermy by 14.5% by evolving lower conductivity, providing support for adaptive evolution of pelage. Our study indicates that selection for lower energetic requirements of homeothermy has shaped evolution of pelage thermal properties. [ABSTRACT FROM AUTHOR]

Summary: The conversion and utilization of aerodynamic heat is one of the most promising thermal management techniques for hypersonic vehicles. In this paper, one‐, two‐ and three‐stage thermoelectric generators (TEGs) are designed and the effects of physical dimensions, temperature ranges and interfacial thermal contacts are studied for a hypersonic cruise vehicle. First, the geometric parameters of TEGs are optimized, and the optimal physical dimensions under different temperature ranges are obtained in consideration of both power supply and weight increment. Second, the effects of interfacial thermal contacts between TE and electrode materials are studied considering the contacting pressure, temperature and gap medium by two‐scale simulations, the thermal contact resistance in micro roughness‐scale and the TE performance of TEGs in meso layer‐scale. Finally, the TEG is considered as a multi‐functional thermal protection structure, and its power generation capacity and weight increment cost are evaluated for a typical hypersonic cruise vehicle. The results show that for different temperature ranges there exist optimal physical dimensions, and greater contact pressure and stronger thermal conduction property of gap medium result into better performance of TEGs. [ABSTRACT FROM AUTHOR]

Accurately simulating the temperature field of frozen shaft lining in its early age (28 days) is difficult due to the influence of low temperature freezing and the heat of hydration in concrete. The temperature-dependent variation of the thermal properties of concrete and surrounding rock makes the simulation even more challenging. This study proposed a simulation method by considering the concrete maturity to characterize the spatiotemporal variation of temperature field in early age. In accordance with Arrhenius and heat conduction theories, a 3D temperature field control equation containing a model of hydration exothermic with equivalent age was established. The thermal parameters of rock and concrete at different temperatures were obtained through laboratory tests, and the temperature field of the lining was analyzed numerically by using ANSYS Parametric Design Language. The reliability of this method was verified by comparing with the measured data. Comparison results show that the proposed model successfully reflects the facts that the maximum temperature rise at different locations of the lining and the time taken to reach the maximum temperature rise are different. The temperature field in the early age shows five stages: induction period, linear growth period, nonlinear growth period, cooling period, and stabilization period. In the first 3 days, the temperature gradient between the inside and outside of the lining is large, which is prone to early temperature damage. This study provides a significant reference for early temperature damage and lining structure design optimization. [ABSTRACT FROM AUTHOR]

There is a scientific debate whether oxygen concentration may be a factor driving the pattern of size decrease at higher temperature. Central to this debate is the fact that oxygen availability relative to demand for living organisms decreases with increasing temperature. We examined whether rotifers Lecane inermis exposed to hypoxic conditions would evolve smaller sizes than rotifers exposed to normoxic conditions, using experimental evolution with the same fluctuating temperature but differentiated by three regimes of oxygen availability: normoxia, hypoxia throughout the whole thermal range, and hypoxia only at the highest temperature. Immediately after the six-month experiment (more than 90 generations), we tested the plasticity of size responses to temperature in three post-evolution groups, and we related these responses to fitness. The results show that normoxic rotifers had evolved significantly larger sizes than two hypoxic rotifer groups, which were similar in size. All three groups displayed similar plastic body size reductions in response to warming over the range of temperatures they were exposed to during the period of experimental evolution, but they showed different and complex responses at two temperatures below this range. Any type of plastic response to different temperatures resulted in a similar fitness pattern across post-evolution groups. We conclude that (i) these rotifers showed a genetic basis for the pattern of size decrease following evolution under both temperature-dependent and temperature-independent hypoxia; and (ii) plastic body size responds consistently to temperatures that are within the thermal range that the rotifers experienced during their evolutionary history, but responses become more noisy at novel temperatures, suggesting the importance of evolutionary responses to reliable environmental cues. [ABSTRACT FROM AUTHOR]

We report on a series of controlled computational experiments based on nonequilibrium molecular dynamics and show that at the nanoscale, the thermal rectification is determined by the thermal boundary resistance, i.e., the thermal resistance of the interface, and cannot be explained without it. In the graphene–bilayer graphene system that we study, the sign of the thermal rectification is opposite to the value predicted from bulk-derived models, i.e., phonons preferentially flow in the opposite direction. This behavior derives from the temperature dependence of the thermal boundary resistance and from the fact that the latter, at the nanoscale, has large relative weight compared to the total thermal resistance. These results outline the importance of properly accounting for the active role of the interface. [ABSTRACT FROM AUTHOR]

The temperature dependence of the electrical properties of composites formed by biphasic sodium titanate and poly(o-methoxyaniline) (Na2Ti3O7/Na2Ti6O13/POMA) with different concentrations of POMA (0%, 1%, 10%, 15%, 35% and 50%) in the ceramic matrix was determined from measurements of complex impedance. The structural details were studied by means of X-ray diffraction, confirming the formation of the Na2Ti3O7/Na2Ti6O13/POMA composites. The displacement of the (200) reflection from 2θ = 10.45° to 11.15° in the composites with 10 and 15% of POMA suggested the partial replacement of H+ for Na+ in the Na2Ti3O7 structure. The thermal properties were investigated by Thermogravimetry and Differential Thermal Analysis. The Thermogravimetry curves of the composites with POMA content of 1, 10 and 15% presented profiles similar to that of pure sodium titanate sample. The composites with 35 and 50% of POMA showed a process at temperatures around 60–70 °C, which was associated with water absorbed by the polymer. The analysis of the complex impedance spectroscopy measurements revealed that the electrical resistivity of the composites in the range from 0 to 35% increased by two orders of magnitude, with different values for each concentration. This positive temperature coefficient of resistivity was less noticeable in the composite with highest POMA mass content (50%). The rapid increase in resistivity caused an increase in the relaxation time calculated from the time domain. The electrical response of the 50% of POMA compound changes in relation to what was observed in the other compounds, which suggests that there is a saturation limit in the increase in resistivity with POMA content. [ABSTRACT FROM AUTHOR]

Maintenance of adequate thermal properties is critical for correct operation of a gas foil bearing. In this work, the authors present the results of the experimentally conducted thermal characterization of a prototype installation of the bearing. A novel method of temperature identification, based on integrated thermocouples readings, has been employed to determine the thermal properties of the specialized sensing top foil mounted in the tested bearing. Two measurement campaigns have been subsequently completed, applying freely-suspended and two-node support configurations, to gather complementary knowledge regarding the bearing's operation. Apart from the rotational speed and temperature field measurements, the authors have also studied the friction torque and the shaft's journal trajectories based on its radial displacements. The temporal courses for the above-mentioned quantities have enabled inference on the effects present during run-up, run-out and stable state operation at a constant speed. As confirmed, the applied distribution of the integrated sensors allows for temperature readings on the entire outer surface of the foil, and therefore, provides useful data for the bearing characterization. The work is concluded with presentation of the recommended directions regarding future improvements of the proposed measurement technique and more comprehensive study of the bearing's characteristics. [ABSTRACT FROM AUTHOR]

Although KNN‐based ceramics with high electrical properties are obtained through a variety of strategies, the temperature sensitivity is still one of the key technical bottlenecks hindering practical applications. Here, we use a new strategy, meticulously tailoring phase boundary, to refine the ferroelectric boundary of KNN‐based ceramics, leading to high piezoelectricity companied with improving temperature stability. The highest d33 value in this system reaches 501 pC/N with a TC ∼ 240°C, whereas a large strain of ∼0.134% can be kept with 10% lower deterioration until 100°C. The origin of high piezoelectricity is mainly attributed to the well‐preserved multiphase coexistence and the appearance of nanodomains, which greatly facilitate the polarization rotation. Instead of the changed intrinsic thermal insensitivity, the precision phase boundary engineering plays an important role in strengthening the temperature stability of electric‐induced strain. This work provides a simple and effective method to obtain both high electrical properties and excellent thermal stability in KNN‐based ceramics, which is expected to promote the practical applications in the future. [ABSTRACT FROM AUTHOR]

Thermoresponsive self-crimping polybutylene terephtlate (PBT)-based bicomponent fibers were fabricated by melt-spinning to serve as primary constituents for textiles, such as nonwoven battings, for an adaptive single insulting layer. Due to the intrinsically mismatching modulus and coefficient of thermal expansion (CTE), the fibers curl or straighten with temperature, similar to the concept of Timoshenko's bimetallic strip. Maximizing the curvature is driven by an optimum of fiber diameter, overall CTE, and fiber moduli, which are all affected by drawing ratio and, consequently, fiber's microstructure. A draw ratio of 2.33 yielded the best combination of mechanical and thermal properties; it was observed that increasing the draw ratio does not necessarily increase the self-crimping behavior. Tests performed on non-woven battings of these fibers exhibited comparable thermoreponsive behaviors to polypropylene-based thermoresponsive fibers from previous studies in the −20 °C to 20 °C temperature range, which has potential for wearable insulations for both commercial and defense sectors alike. [ABSTRACT FROM AUTHOR]

Herein, we successfully carried out the of CdS nanowires doped with CdSO4 nanoparticles by arc discharge method. For this, two cadmium rods with high purity as anode and cathode electrodes were submerged in a liquid nitrogen medium. The cathode electrode was filled with micro-sized sulfur powder to synthesize CdS nanowires. CdS nanowires were obtained by oxidation using low temperature with CdSO4 nanoparticles. After the arc discharge process, the resultant product was characterized to reveal structural and morphological properties. XRD and electron EDX analyses exposed the coexistence of the CdS and CdSO4 phases. Scanning electron microscopy (SEM) investigations revealed that the synthesized nanostructures formed in a 1D wire nanostructure morphology with a diameter of less than 10 nm and several micrometers in length. Besides, the transmission electron microscopy (TEM) analysis was utilized to monitor the CdSO4 nanoparticles located on CdS nanowires surface. It has been found that the absorption band blue-shifted with 0.53 eV. This blue shift originated from the quantum confinement in the nanoparticles. [ABSTRACT FROM AUTHOR]

Polypropylene (PP) is a crystalline thermoplastic widely used in many industrial applications such as medical devices, automotive parts, battery cases, household products, or packaging trays due to its high chemical resistance, processability and impact/stiffness balance, well barrier property, lightness and toughness respectively. However, researchers and engineers have focused on new injection methods to reduce the cost of products and production time. After doing a literature survey about the new injection methods in this study, the co-injection simulation conducted with the Moldex 3-D program using properties of both virgin PP and scrap PP. By the way, the effect of co-injection parameters such as injection pressure, closing force, mod and melt temperatures on co-injection filling characterization investigated. As a result that when the core temperature of the first injected virgin PP is higher than its nucleation temperature, the core of the wall goes on the wall with the second injection of scrap PP until cooling of nucleation temperature. End of co-injection, the second injected scrap PP after first injected virgin PP replaced the advancing virgin PP on the wall core, and a three-layered wall consisting of original PP, scrap PP, original PP obtained. [ABSTRACT FROM AUTHOR]

The current trend towards nanotechnology creates possibilities for its use in materials science as manufacturing material with extraordinary properties, and is one of the goals for scientists in this field. Carbon nanotubes in particular are promising due to their electrical, thermal and mechanical properties, which have been of interest for researchers around the world. This paper focuses on the manufacturing process of the Cu-CNT composite via powder metallurgy and KOBO extrusion process, its further cold drawing process, and electrical resistance test at an elevated temperature. As obtained data proved, the higher the CNT content the lower the electrical resistance. [ABSTRACT FROM AUTHOR]

The aim of this paper is to investigate the thermal behavior of composite building materials comprised of silt and flax fibers, considering various initial conditions. The experiments were conducted on flax fibers alone, examining factors such as moisture content variation, fibers arrangement, and density. Subsequently, the thermal properties of the earth-flax fiber composite were studied, taking into account the influence of water content and fibers mass content. The thermal properties of both flax fibers and raw earth-flax fibers composite specimens were determined using the experimental unsteady-state method. The results indicate that the thermal conductivity and heat capacity of flax fibers increase with density, temperature, and moisture content. Regardless of fibers density and arrangement of fibers, linear relationships have been established for both thermal conductivity and heat capacity as functions of temperature. Additionally, it was demonstrated that the heat capacity and the thermal conductivity increase with water content, regardless of the percentage of added fibers. Moreover, mixing randomly flax fibers with compacted raw earth material has improved the thermal properties of the composite. This improvement pertains to its insulating capacity, ability to store heat, and, subsequently, its contribution to the thermal comfort provided by such earth composite material when used as a building material. • Thermal conductivity enhances by increasing the moisture content and density. • The arrangements of fibers have highly influenced the thermal properties. • Linear relationships were established for the thermal conductivity and heat capacity. • The addition of flax fibers to raw earth improved the thermal properties. [ABSTRACT FROM AUTHOR]

Medium frequency transformer (MFT) plays a key role in future power systems and new energy systems. It is very important for the safe operation of MFT to correctly calculate the temperature rise and hot spot position. According to the heat dissipation of transformer, the equivalent thermal network model of the core-type transformer is established in this paper. The traditional thermal network model ignores the heat dissipation of the magnetic core column and the inner surface of the yoke to the air. In this paper, the magnetic core column is divided into the air surrounding part and winding surrounding part. The heat dissipation on the inner surface of the yoke is further considered. The improved thermal network model is verified by finite element simulation. The results show that compared with the traditional thermal network model, the improved thermal network model proposed in this paper can more comprehensively analyse the temperature field distribution and calculate the node temperature more accurately. [ABSTRACT FROM AUTHOR]

The thermal and mechanical effects induced in tissue by ultrasound can be exploited for therapeutic applications. Tissue-mimicking materials (TMMs), reflecting different soft tissue properties, are required for experimental evaluation of therapeutic potential. In the study described here, poly(vinyl alcohol) (PVA) hydrogels were characterized. Hydrogels prepared using different concentrations (5%-20% w/w) and molecular weights of PVA ± cellulose scatterers (2.5%-10% w/w) were characterized acoustically (sound speed, attenuation) as a function of temperature (25°C-45°C), thermally (thermal conductivity, specific heat capacity) and in terms of their cavitation thresholds. Results were compared with measurements in fresh sheep tissue (kidney, liver, spleen). Sound speed depended most strongly on PVA concentration, and attenuation, on cellulose content. For the range of formulations investigated, the PVA gel acoustic properties (sound speed: 1532 ± 17 to 1590 ± 9 m/s, attenuation coefficient: 0.08 ± 0.01 to 0.37 ± 0.02 dB/cm) fell within those measured in fresh tissue. Cavitation thresholds for 10% PVA hydrogels (50% occurrence: 4.1-5.4 MPa, 75% occurrence: 5.4-8.2 MPa) decreased with increasing cellulose content. In summary, PVA cellulose composite hydrogels may be suitable mimics of acoustic, cavitation and thermal properties of soft tissue for a number of therapeutic ultrasound applications. [ABSTRACT FROM AUTHOR]

The nuclear structure and thermal quantities of the superheavy nucleus of 2 9 2 1 2 0 1 7 2 are studied in a recent developed framework of the Finite-Temperature Hartree–Fock–Bogoliubov (FT-HFB) by using a zero-range pairing and including the continuum effects. Analyzing the shell structure of this nucleus at both zero and finite temperature shows a dependence on the various Skyrme-type forces used and a shell closure occurrence at Z = 120 for protons and N = 172 for neutrons with a large gap energy where the pseudo-spin-orbit effects play a primordial role in the shell sequence at finite temperature which confirm the double magicity of 2 9 2 1 2 0 1 7 2 . Thermodynamic quantities are also studied in the same framework where the results are qualitatively similar to what are obtained in case of the hot ordinary nuclei. [ABSTRACT FROM AUTHOR]

The ampacity of buried cables is significantly influenced by the thermal properties of the burial environment. When these thermal properties are not homogeneous it is usually necessary to utilize simulations with a relatively high computational cost that may also use commercial software. In this paper an alternative approach is proposed using conformal maps. Temperature is calculated in an annular domain which is a conformal mapping of the half plane space. Circumferential dependence is captured by expanding temperature as a Fourier series, a finite difference solver then determines temperature components radially. The model is as flexible as any two-dimensional slice model of heat transfer through thermal conduction only. Two case studies are considered: three land-based cables in planar configuration and a submarine export cable. The thermal properties of both burial environments are based on conditions which may be encountered in the field and exhibit a high level of stratification. Using a finite element analysis simulation as a benchmark, typical percentage differences in cable ampacities were 0.5%−1%. In addition to accuracy and flexibility the low computational cost of the proposed approach allows for large parameter sweeps, which may be required in a design phase, without requiring commercial software. [ABSTRACT FROM AUTHOR]

Hydroxyl-terminated polyether (HTPE) propellant and HTPE/Poly(ε-caprolactone) (PCL) propellant were compared to explore the effects of introducing PCL to HTPE propellant on the mechanical and thermal properties at the wide temperature range of − 50 °C to 70 °C. The energetic properties of HTPE and HTPE/PCL propellants were also evaluated, the ideal specific impulse and density of HTPE/PCL propellant were found to be slightly enhanced comparing with those of HTPE propellant. The tensile mechanical properties results revealed that the introduction of PCL could improve the maximum tensile strength (σm) of HTPE/PCL propellant at the wide temperature range of − 50 °C to 70 °C, its σm increased from 0.38 to 0.75 MPa at 20 °C, 0.25 to 0.48 MPa at 70 °C and 4.01 to 4.77 MPa at − 50 °C separately comparing with those of HTPE propellant. The thermal decomposition behavior at 0.1 MPa showed that the introduction of PCL could promote RDX and AP in HTPE/PCL propellant to decompose. Bu-NENA was hardly to evaporate from HTPE/PCL propellant at higher pressure, which was beneficial to its thermal decomposition. The introduction of PCL could be more effective to inhibit the evaporation of Bu-NENA from HTPE/PCL propellant at 0.1 MPa, the activation energy of evaporation of HTPE and HTPE/PCL propellants was 53.66 kJ mol−1 and 77.90 kJ mol−1, respectively. [ABSTRACT FROM AUTHOR]

Cold protective clothing directly affects outdoor workers' health and work efficiency in winter, and a good performance is particularly needed. This article studies a lightweight smart cold-proof clothing material. Its thermal insulation and heating performance are analyzed theoretically, and its temperature adaptability is obtained, which sheds new light on the design of cold protective clothing. [ABSTRACT FROM AUTHOR]

As a promising environmentally friendly insulating medium, C5F10O needs to be mixed with buffer gases such as technical air to avoid liquefaction. Notably, such a high proportion of oxygen can promote the decomposition of C5F10O and may even eradicate its stability under over-thermal fault. At present, there is still a lack of experimental research investigating the influence of oxygen on the thermal stability of C5F10O, and the mechanism is still unclear. To this end, experiments are carried out on the thermal decomposition properties of C5F10O while mixed with different proportions of O2. And to reveal the mechanism, the dissociation of C5F10O and the reaction of O2 with CF3CO $\cdot $ radical are studied theoretically based on the density functional theory (DFT) and transition state theory (TST). The results signify that oxygen of 4% and above ravages the thermal stability of C5F10O medium, causing it to decompose in a large amount at high temperature, which generates stable products such as CO2, C3F6, C3F8, and C2F6. The mechanism is that O2 is extremely easy to combine with CF3CO $\cdot $ radical to form a complex, which further decomposes, leading to the continuous development of the decomposition of C5F10O. The study revealed the important mechanism of O2 during the decomposition process of C5F10O, providing experimental and theoretical support for the use of C5F10O mixed gas. [ABSTRACT FROM AUTHOR]

The Cold Pool feature of the Middle Atlantic Bight (MAB) is a body of cold bottom water that develops in the spring and persists through the summer‐autumn months. It is maintained by northerly currents and can be traced back to Arctic water masses. The Cold Pool provides habitat for many boreal species at latitudes far south of their normal range and plays an important role in the population dynamics of lower and upper trophic level organisms. Here, we describe changes in the extent and thermal properties of the Cold Pool using both observations and models. Two indices are developed based on a gridded, interpolated bottom temperature dataset; the first is a mean temperature indicator, and the second is a spatial extent indicator. The temperature indicator showed a significant increasing trend over the study period 1968–2019 and a single change point in 2008. Similarly, the area indicator declined significantly, also displaying a change point in 2008. Cold Pool maximum temperature and minimum size were observed in 2017, which is also known as a heatwave year in the MAB. The indices presented here support the view of a rapidly warming Cold Pool that is being limited in its spatial extent. Changes in Cold Pool hydrography will likely affect boreal species distributions and total ecosystem productivity. [ABSTRACT FROM AUTHOR]

In this review article, we have investigated the credibility and suitability of the lanthanum gallium silicate (La3Ga5SiO14, LGS) crystals in the application of high-temperature sensing. All the basic properties of the langasite family piezoelectric crystals, such as elastic properties, are taken into consideration and discussed. The crosstalk effects between different vibration modes of LGS crystal are investigated to optimize the crystal cuts. Thereafter, dependences of properties, such as electroelastic properties, resistivity, and electromechanical coupling coefficients of langasite family crystals on higher temperatures, are discussed. Finally, thermal-related properties of langasite family crystals, such as specific heat as well as thermal expansion coefficients, are studied for higher temperature ranges and a comparison with other piezoelectric crystals has also been presented. [ABSTRACT FROM AUTHOR]

We characterized the thermal behavior of a 65 nm bulk CMOS transistor, by measuring the self-heating effect (SHE) as a function of bias condition. We demonstrated that at a base temperature of 6.5 K the channel temperature of the transistor can increase up to several tens of kelvins due to power dissipation. The thermal behavior of the transistor is determined not only by the thermal response of the transistor itself but also by the thermal properties of the surroundings, i.e., source, drain, bulk, and gate interfaces, metal contacts, and vias. On top of it, the thermal response is bias-dependent through bias dependence of power and self-heating. This information becomes relevant for proper design of integrated circuits for quantum computing or other cryogenic applications, where the circuitry requires to be operated at a stable cryogenic temperature. [ABSTRACT FROM AUTHOR]

Despite its wide range of real-life applicability, the combined effect of the thermal properties and thickness of a heater on the Leidenfrost temperature (T L) of the system has not been explored. Thus, this study investigates the effects of thermal properties and thickness on the T L using four different metal specimens (Inconel 718, AISI 304 stainless steel, brass, and aluminum). Our experimental results show that the T L decreases with an increase in the thickness of the specimens up to a threshold value. Herein, this varying T L , which varies with thickness, is called transient Leidenfrost temperature (T L,TR) in this study. When the thickness of the sample exceeds the asymptotic thickness, T L became constant, which is termed as the asymptotic Leidenfrost temperature (T L,ASY) in this study. The dependency of the Leidenfrost phenomenon on the thermal properties and thickness can be described by simultaneously considering the heat capacity and heat propagation characteristics; however, in case of the thick specimens, the T L,ASY is mainly considered to be resultant of the speed of heat propagation, including the heat-transfer performance. Consequently, two different trends of the Leidenfrost phenomenon can be predicted. • Leidenfrost temperatures decrease as the thickness of specimens increases to an asymptotic thickness. • Transient Leindenfrost temperature is simultaneously affected by both heat capacity and thermal conductivity. • Asymptotic Leindenfrost temperature is mainly affected by thermal conductivity. • Leidenfrost temperatures are predicted from a transient heat conduction analysis based on the droplet dynamics. [ABSTRACT FROM AUTHOR]

• The thermal cloak in homogeneous isotropic multilayer materials is analyzed. • The influences of the layer's properties in the thermal cloak on the thermal control ability are investigated. • The temperature field of the arbitrary layout composite thermal cloak can be predicted by the deep learning model with almost no time cost. Thermal cloaks can realize thermal manipulation and have been widely applied in the engineering field. Traditional methods, like the finite element method (FEM) and finite difference method, obtain the temperature of the thermal cloak with time-consuming. A deep learning model is proposed to predict the temperature field in homogeneous isotropic multilayer materials. The FEM is applied to solve the thermal cloak and the training data are obtained. The layer's properties, including different layers, thickness, relative thermal conductivities and distribution modes, of the thermal control or manipulative ability for temperature and heat diffusion are also investigated. The deep learning mode is developed by mapping the parameters layout to the temperature field as an image-to-image regression task and the relationship between the layer's properties and the cloaking performances is intelligently established. The temperature field of the arbitrary layout composite can be acquired almost with no time cost. The temperature field with the largest node numbers of medium temperature by the FEM and the deep learning model, is exhibited and compared. Furthermore, we extend the surrogate model to different cases with different boundary conditions, which can still achieve good prediction results. Owing to the high efficiency and complete independence from the mesh densities, the proposed method offers a novel and robust technique for predicting the temperature field and suggestion for the design of the thermal cloak. [ABSTRACT FROM AUTHOR]