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The chitosan (CS) transparent film has attracted much attention in food and medicine packaging areas due to their biodegradability and good availability. A novel carbon quantum dots compound containing nitrogen and phosphorus (NP-CQDs) was obtained by reacting citric acids, with urea and phytic acids. The density of the film was increased, and the water vapor permeation was reduced by the presence of NP-CQDs. The introduction of 4 wt% NP-CQDs increased the water contact angle of the CS film from 79.2° to 105.8°. The shielding on UV-A and UV-B transmittance was increased with the NP-CQDs loading. The film containing 4 wt% NP-CQDs blocked more than 90.2% UV-A and 96.5% UV-B; however, it only blocked 26.8% visible light. It also exhibited better antibacterial activity to both E. coli and S. aureus than the control CS film. This work provided a feasible way to prepare multifunctional bio-safe film., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

In the years 2022 and 2023 we investigated the prevalence of the ovulatory failure in 133 mares of different breed, 3 to 24 years old, brought to the Equine clinic of the University of Veterinary Medicine and Pharmacy (UVMP) in Košice. Our research involved the monitoring of the reproduction cycle in these mares with the aim to determine the prevalence of ovulatory failure during the breeding season, focusing on certain specific parameters that were considered sufficiently relevant with respect to the development of such failure. These parameters included environmental temperature and the amount of daylight the mares were exposed to, attributable to the months of the breeding season. In addition, we also evaluated the size of pre-ovulatory follicles and the influence of age of the investigated mares. During the mentioned years, one of the ovulatory failures occurred in 17 out of 133 mares (12.78 %). Examination by ultrasonography (USG) and the subsequent analysis of the occurrence of failures in relation to the investigated parameters allowed us to conclude that the length of daylight, age, and environmental temperature were the most important factors. Our observations indicated that the 15–16 h category of daylight presented the highest risk of development of cycle disorders with the most rapid increase observed for HAF. With respect to age, the highest occurrence of ovulatory failures was observed in the category of 15–24 years. The external temperature in the range of 18.1–23.0 °C affected the most the development of cycle disorders. Again, the effect was most evident with respect to HAF. This resulted in our recommendations for horse breeders that they should manage reproduction of their mares in a way so that the receptive phase of the cycle does not occur in the months during which the daylight length and environmental temperatures support ovulatory failure. We also recommend that if the owner′s wish is to keep in the breeding the mares older than 15 years, regular thorough gynaecological examination of these animals should be ensured, aimed at early diagnosis of ovulatory failure. [ABSTRACT FROM AUTHOR]

We investigate the temperature and magnetic field-dependent electrical and thermal properties of Eu2.2Ga11Sn35, revealing a change in electronic structure and an increase in magnetoresistance with increasing field, as well as the origin of magneto-suppressed thermal conductivity of this unconventional inorganic clathrate-I material with very low cation concentration. [ABSTRACT FROM AUTHOR]

We investigate the temperature and magnetic field-dependent electrical and thermal properties of Eu2.2Ga11Sn35, revealing a change in electronic structure and an increase in magnetoresistance with increasing field, as well as the origin of magneto-suppressed thermal conductivity of this unconventional inorganic clathrate-I material with very low cation concentration. [ABSTRACT FROM AUTHOR]

The spatial ecology of animals is influenced by the structure of their physical habitat, which affects the availability of refuges and microclimate, as well as the spatial positioning of resources. The use of space by the lizard Liolaemus tandiliensis was investigated in the Tandilia mountains of the Pampas region. We radio-tracked 19 adult lizards and found that home range size and distance moved were significantly affected by sex, with males having a home range 34% larger and moving longer distances than females. These parameters were also influenced by structural and thermal features of specific microhabitat types. The habitat structure inside the home range showed relatively high coverage of rocks and low coverage of vegetation. The thermal properties of the microhabitats were strongly associated with their occupancy; individuals used microhabitats of high thermal quality that exhibited environmental temperatures deviating the least from the preferred body temperature range of L. tandiliensis. Small-scale structural heterogeneity and thermal gradients were available in the Tandilia mountains, so L. tandiliensis individuals may not need to move large distances and may sustain themselves within a relatively small home range (mean=74.52 m2). Our findings suggest that L. tandiliensis occurs in a delicate balance with its specific habitat. This study provides information that must be taken into account for conservation planning, especially in light of the increasing anthropogenic degradation of the Tandilia mountains. [ABSTRACT FROM AUTHOR]

To study the service performance of polymer bilayer sheets, this experimental study focuses on the thermal and mechanical characterization of sheets composed of two polymer layers (named ABS/PMMA), an Acrylonitrile–Butadiene–Styrene layer and a 15% Poly(Methyl Methacrylate) layer. These sheets are used in many industrial components subjected to thermal and mechanical strain. The studied bilayer sheets were obtained by a co-extrusion process. Thermal properties were measured through Thermogravimetric Analysis (TGA) and Differential Scanning Calorimetry (DSC). Mechanical behavior was determined via uniaxial tensile tests at various temperatures less than the glass transition temperature and using two strain rates of 3.33 × 10−4 s−1 and 1.66 × 10−2 s−1. Furthermore, the viscoelastic properties are determined via Dynamic Mechanical Analysis (DMA) using two frequencies. The findings revealed substantial ABS/PMMA bilayer thermal stability. The obtained glass transition temperature of this bilayer was 111 °C. Its viscoelastic behavior was described by determining the storage and loss modulus. Furthermore, the influence of temperature and strain rate parameters on the tensile behavior of the ABS/PMMA bilayer was also determined showing high dependence of mechanical behavior on these two parameters. This bilayer exhibits brittleness at room temperature and high total strain exceeding 62% at 90 °C. [ABSTRACT FROM AUTHOR]

The chalkiness, starch fine structure, and physiochemical properties of rice starch were analyzed and their correlations were investigated under different nighttime temperatures during the early grain-filling stage. Compared to MT, medium temperature (MT) and low (LNT) and high (HNT) nighttime temperatures resulted in an increased chalky grain rate (CGR) and chalkiness degree (CD). LNT mainly affected the chalkiness by increasing peak1 (short branch chains of amylopectin), the branching degree, and the proportion of small starch granules but decreasing peak2 (long branch chains of amylopectin) and peak3 (amylose branches). This altered the pasting properties, such as by increasing the peak viscosity and final viscosity. However, HNT mainly affected the chalkiness by increasing peak2 and the crystallinity degree but decreasing peak1 and peak3. Regarding the thermal properties, HNT also elevated peak and conclusion temperatures. The CGR and CD were significantly and positively correlated with the proportions of small and medium starch granules, peak1, branching degree, gelatinization enthalpy, setback viscosity, and pasting time but markedly and negatively correlated with the proportion of large starch granules, amylose content, peak3, peak viscosity, and breakdown viscosity. These findings suggest that LNT and HNT disrupted the starch structure, resulting in increased chalkiness. However, their mechanisms of action differ. [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]

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]

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]

Since the fusing process in electrophotography has a significant impact not only on printing quality but also on machine internal temperature and toner blocking on outlet tray, accurate paper temperature prediction for various types of papers is essential, especially in the production printing. To develop the thermophysical model of fusing process to predict the paper temperature after the fusing process, thermal properties such as thermal conductivity, specific heat, and thermal contact resistance of several types of papers are necessary. However, paper is composed of complex fiber, surface coating, filler, and moisture, making it difficult to measure thermophysical properties of paper accurately. This work developed a machine learning (ML) model that can predict the thermophysical properties of paper based on a conventionally used 1D thermal network model of the fusing process and experiment results. The thermophysical properties of each paper obtained by ML and the thermophysical properties obtained by the conventional method were input to the thermal network model to predict the paper temperature after the fusing process and compared with the measured paper temperatures of the experiment. The results showed that the paper temperature was predicted with higher accuracy by using thermophysical properties obtained by ML than that by the conventional method. Although the method for predicting paper temperature by using only ML had been proposed, it had the disadvantage of requiring a large number of training experiments. In contrast, this method trained under the conditions of one fusing temperature and two printing speeds, and was able to predict under five fusing temperatures and four printing speeds. [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]

The influential effects of thermal treatment on material density, hardness, colour and microstructure of three commercially available woods in South Asia are evaluated. Wood specimens are isochronally annealed 120 min at different temperatures up to 250°C and isothermally annealed at 100°C, 150°C and 225°C up to 480 min under atmospheric pressure. Heat treatments cause density loss, hardness loss, darkening and microstructure frailer of woods, as the maximum temperature was increased. However, thermal treatment up to the temperature around 150°C shows lower values for the case of density, higher values for hardness and no remarkable changes in colour of wood specimens. Higher temperature treated samples are found to recover through absorbing water (moisture); however, chemically bonded water and thermally lost substances cannot be recovered. The diffuse reflectances of all the wooden samples decrease with the increase of annealing temperature, especially at colour band of higher wave length. The negative effects of the high-temperature thermal treatment on the properties of all the woods are observed due to removal of the free, loosely and chemically bonded water of woods, along with higher thermal degradation of cellulose, hemicelluloses and lignin. The SEM microstructures of the wood samples also comply with the present investigation showing the damage structure of fibres and pores. [ABSTRACT FROM AUTHOR]

The ground surface of green parks in arid and semi-arid areas may not be comfortable at specific times during the day and night due to the sun and the rate at which the subsoil gains or loses heat. Knowledge of the subsurface soil's thermal properties can provide designers with convenient and comfortable settings. Design focus is generally directed toward stability, density, and hydraulic conductivity. An assessment of the thermal properties of clay–sand mixtures of 10%, 20%, and 30% clay content is conducted. The proposed clay–sand layers are subjected to three different thermal gradients of 30, 20, and 10 degrees of magnitude. The profile of temperature changes was monitored using 5TE sensors and data loggers. The mixtures were also subjected to cooling at room temperature. The results indicate that the clay type and the clay content govern the response of subsurface clay–sand liners to temperature gain and loss. Two field sections with clay–sand layers of 15% and 20% clay were examined for temperature changes over an extended period. In winter, green areas rich in clays were found to keep heat for several hours and provide relatively warm evenings. In summer, the mixture retains a cool temperature for some time during the day. [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]

The effect of moisture absorption and temperature on the thermal properties of dried tigernut was studied. The proximate composition includes moisture content ranging from 0.97% to 6.45%, Ash content from 0.63% to 1.93%, fat from 12.95% to 16.63%, crude fiber from 18.71% to 33.78%, and carbohydrate from 43.58% to 58. 68%. The thermal properties were determined by using the value obtained from the proximate composition and calculated using the Okoi and choi's equation. The value obtained from the thermal properties are thermal conductivity which ranged from 0.28866 w/moc to 0.3562 w/moc, thermal diffusivity ranging from 0.1123m2/s to 0.2172ms/s and specific heat capacity ranging 1.8484 kg/kgoc to 1.9261 kg/kgoc. The percentage moisture absorption capacity was also analyzed in the sample which ranged from 46.6% to 94.4%. Thermal properties refer to the response in their temperature. The result obtained showed that the sample conditioned at 100°C had the highest thermal properties and this implied that the thermal properties of food is generally influenced by moisture, temperature and their proximate composition. Further studies should be carried out on the Rheological properties of tigernut, kinetic rate of reaction of the nutrient with respect to time and the thermal properties should be utilized for the design of equipment and for the mathematical model in terms of simulation and mass heat transfer in the material. [ABSTRACT FROM AUTHOR]

This paper focuses on the thermal properties of R-Glass/Epoxy laminate in response to temperature variations. The elastic properties and coefficient of thermal expansion in the material's principal direction were measured across the temperature range from room temperature to the cure temperature. These properties were then characterized as functions of temperature. Using the characterized properties and the principles of classical lamination theory, a method was proposed to predict the changes in the coefficient of thermal expansion for a general laminate subjected to temperature variations. The measured values of the coefficient of thermal expansion for laminates with varying angle plies were compared with the predicted values. The experimental results demonstrate that the proposed method accurately predicts the changes in the coefficient of thermal expansion for a general laminate under temperature variations. Additionally, an analytical formulation was proposed and validated to predict the changes in the coefficient of thermal expansion for R-Glass/Epoxy laminates subjected to temperature variations. [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]

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]

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]

This work is focused on the performance of three different standard-cell-based comparator topologies, considering ultra-low-voltage (ULV) operation. The main application scenarios in which standard-cell-based comparators can be exploited are considered, and a set of figures of merit (FoM) to allow an in-depth comparison among the different topologies is introduced. Then, a set of simulation testbenches are defined in order to simulate and compare the considered topologies implemented in both a 130 nm technology and a 28 nm FDSOI CMOS process. Propagation delay, power consumption and power–delay product are evaluated for different values of the input common mode voltage, as a function of input differential amplitude, and in different supply voltage and temperature conditions. Monte Carlo simulations to evaluate the input offset voltage under mismatch variations are also provided. Simulation results show that the performances of the different comparator topologies are strongly dependent on the input common mode voltage, and that the best values for all the performance figures of merit are achieved by the comparator based on three-input NAND gates, with the only limitation being its non-rail-to-rail input common mode range (ICMR). The performances of the considered comparator topologies have also been simulated for different values of the supply voltage, ranging from 0.3 V to 1.2 V, showing that, even if standard-cell-based comparators can be operated at higher supply voltages by scaling their performances accordingly, the best values of the FoMs are achieved for V D D = 0.3 V. [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]

In this study, we explored the electrical characteristics of micro‐LEDs with various pixel sizes on GaN substrates, demonstrating that small sizes have high current density due to superior current spreading. Due to the p‐electrode ohmic contact's temperature dependence, which is supported by TLM measurements, the ideal factor declines as temperature rises. We also show the temperature sensitivity in proportion to device size at a certain current density, which is susceptible to carrier non‐radiative recombination brought on by surface defects. We comprehensively present the thermal properties of GaN‐on‐GaN homoepitaxy micro‐LEDs, laying the groundwork for improved device stability and reliability. [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, we explored the electrical characteristics of micro-LEDs with various pixel sizes on GaN substrates, demonstrating that small sizes have high current density due to superior current spreading. Due to the p-electrode ohmic contact's temperature dependence, which is supported by TLM measurements, the ideal factor declines as temperature rises. We also show the temperature sensitivity in proportion to device size at a certain current density, which is susceptible to carrier non-radiative recombination brought on by surface defects. We comprehensively present the thermal properties of GaN-on-GaN homoepitaxy micro-LEDs, laying the groundwork for improved device stability and reliability. [ABSTRACT FROM AUTHOR]

High-entropy materials have been widely researched in recent years, and more work on their thermal and electrical properties is still needed. Herein, we fabricate a high-entropy carbide (Ti0.2Zr0.2Nb0.2Hf0.2Ta0.2)C ceramic and report the thermal and electrical conductivity at room temperature using first-principles calculations and experiments. The movement of phonons is suppressed in high-entropy carbides when analyzing the thermal and electrical conductivity at room temperature, but the movement of electrons is not. After the first-principles calculations on the electronic structure and lattice vibration and experiments, we give the reasons why the rule of mixture can predict electrical conductivity but not thermal conductivity at room temperature. Finally, we outline the cause of the similar lattice patterns between TaC and (Ti0.2Zr0.2Nb0.2Hf0.2Ta0.2)C. [ABSTRACT FROM AUTHOR]

Hydrogels are cross-linked polymeric networks which retain large amounts of water. The hydrogels with response capability to various stimuli such as pH and temperature have received great attention in many fields. In this study, hydrogels were synthesized by free radical solution polymerization through optimization of acrylamide/sodium acrylate mole ratio and ethylene glycol dimethacrylate content. With the addition of sepiolite as filler into the hydrogel network which had highest swelling percent, hydrogel composites were obtained. In the presence of 10 wt% sepiolite, maximum swelling percent was determined as approximately 10600%. Swelling properties of the hydrogel composite including 10 wt% sepiolite was investigated depending on pH, salt effect and temperature. With increasing pH value, swelling percent of the hydrogel composite showed an increase. At high temperatures, the hydrogel composite exhibited higher swelling percent. Swelling tests in 0.1 M NaCl, CaCl2 and FeCl3 solutions revealed that the lowest swelling percent was observed in 0.1 M FeCl3 solution. Fourier transform infrared spectroscopy (FTIR) analyses verified successfully preparation of the hydrogel composites. Regular layers of the sepiolite in the hydrogel network which made water diffusion easily were shown by scanning electron microscopy (SEM) analyses. Thermogravimetric analyses (TGA) indicated that thermal stability of the hydrogel network was increased with the addition of sepiolite. [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]

Simultaneously promoting piezoelectric constant (d33) and depolarization temperature (Td) is often incompatible in BNT-based piezoceramics. Mediating the contradiction of d33 and Td by complex chemical composition and thermal treatment methods severely restricts the development and practical applications of this kind of promising material. In this study, a sustainable plain approach to advancing materials without changing chemical compositions and preparation process is proposed, i.e., a considerable improving Td from 180 to 205 °C with significantly enhancing d33 from 135 to 162 pC/N is achieved in unmodified 0.935(Bi0.5Na0.5)TiO3–0.065BaTiO3 (BNTBT65) ceramics only by simply varying the sintering temperature. The advance in simultaneously achieving a large d33 and a high Td, which goes far beyond the performance boundary limit of d33vs. Td for BNT–BT-based systems, originates from the synergistic effect of increasing εr and grain size and oxygen vacancy. This work provides a facile way to effectively widen working temperature range and simultaneously enhanced piezoelectric properties of BNT-based piezoceramics materials for practical applications and expects to benefit other lead-free piezoelectric materials.Kindly check and confirm the edit made in the title.Yes, we have Kindly checked and confirmed the title and made no changes. [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]

Particular thermal properties of internal energy, entropy, specific heat capacity and pressure are indicated using static fluctuation approximation (SFA) for specified temperatures and densities where the interaction between particles is still valid. This ab initio study starts initially from the most reliable krypton interatomic potential and develops with complementary SFA assumptions that depend mainly on substituting the local field mean value instead of its operator, thus developing a numerical solution of a nonlinear close set equation by iteration technique. The results are matched with the ideal gas and show a considerable sense. [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]

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]

The design and long-term safety of geological repositories for high-level radioactive waste (HLW) are dependent on the precise determination of the thermophysical parameters of mudstone. However, there is no relevant literature on the study of the thermophysical properties of Tamusu mudstone, a prospective rock for HLW disposal in China under the complex HLW disposal conditions. Therefore, in this paper, Tamusu mudstone is examined, and its thermophysical properties are tested at temperatures in the range of 25–80 °C with and without the influence of external forces. The thermophysical parameters exhibited significant anisotropic characteristics and were strongly correlated with temperature. The increase in temperature increases the specific heat capacity while lowering the thermal diffusivity. Due to the external force, the anisotropy of the thermophysical parameters decreases, enhancing the ability of the mudstone to transfer thermal energy. Furthermore, the aforementioned phenomena were interpreted from a microscopic perspective. This work can aid in the thermal-related physical phenomena of argillaceous rock and provide key input parameters for both analytical and numerical modeling in the safety assessment of HLW repositories, and other underground facilities at high temperatures.

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]

Concrete piles in ice-rich areas exist in negative-temperature environments, which seriously affect the concrete's strength. In order to maintain the quality of concrete piles in these areas, the temperature during the concrete strength formation period needs to be controlled. In this paper, the temperature field of the pile body of a test pile with double sheaths filled with polyurethane insulation and one without polyurethane insulation were measured. The temperature disturbance law of the pile base with/without insulation was obtained and comprehensively analyzed. The temperature of the pile body was shown to increase with the thickness of the insulation layer. Analysis of the thermal and physical properties of the insulation materials showed a linear relationship between pile temperature and thermal conductivity, in which a lower thermal conductivity resulted in a higher pile temperature. The effect of applying insulation around the pile perimeter in the ice-rich permafrost region on the concrete strength of the pile foundation was verified. The test pile with insulated double sheaths showed better strength at all ages than the test pile without insulation. The use of insulation maintained the temperature of pile foundations in ice-rich areas and ensured that the pile foundations were in better condition, thus improving the concrete strength at all ages. Adopting a double-sheathing configuration with polyurethane as an insulating layer can improve the concrete strength of the pile. This method is applicable to the ice-rich permafrost area in the Daxinganling Mountains and also has reference value for middle and low-latitude wetland permafrost areas. [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]

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]

Thermometry techniques have been widely developed during the last decades to analyze thermal properties of various fluid flows. Following the increasing interest for microfluidic applications, most of these techniques have been adapted to the microscale and some new experimental approaches have emerged. In the last years, the need for a detailed experimental analysis of gaseous microflows has drastically grown due to a variety of exciting new applications. Unfortunately, thermometry is not yet well developed for analyzing gas flows at the microscale. Thus, the present review aims at analyzing the main currently available thermometry techniques adapted to microflows. Following a rapid presentation and classification of these techniques, the review is focused on optical techniques, which are the most suited for application at microscale. Their presentation is followed by a discussion about their applicability to gas microflows, especially in confined conditions, and the current challenges to be overcome are presented. A special place is dedicated to Raman and molecular tagging thermometry techniques due to their high potential and low intrusiveness. [ABSTRACT FROM AUTHOR]

This research explores the relationship between the temperatures of the solar corona and planetary magnetosheaths. Based on the second law of thermodynamics, the maximum temperature of the planetary magnetosheaths cannot exceed that of the solar corona. A theoretical investigation is presented into the expansion of the solar corona, the propagation of solar wind, and the compression of planetary magnetosheaths by bow shocks. The method used is general and fits the dynamics of multiple components, thermal anisotropy, and non‐Maxwellian plasmas in the steady state, and approximate formulas are obtained. The results indicate that, for the steady state, planetary magnetosheaths at the subsolar points in the solar system have approach peak mean temperatures. Second, a systematic statistical survey of the average temperature of the planetary magnetosheaths is presented and shows that the average plasma temperature of the subsolar point magnetosheaths of Earth and Saturn are 206 eV (2.39 MK) and 171 eV (1.98 MK), respectively, which are close to that of the corona. The statistical results are consistent with the theoretical estimations. These results are of significant use for estimating the thermal properties of the planetary magnetospheres. Plain Language Summary: This research focuses on the relationship between the temperatures of the planetary magnetosheaths and that of the solar corona. It is thus an interdisciplinary problem in solar‐terrestrial physics. A theoretical investigation is presented on the expansion of the solar corona, the propagation of the solar wind, and the compression of the planetary magnetosheath by bow shocks. An approximate formula for the relationship between the temperatures of the solar corona and that of planetary magnetosheaths is obtained. The quantitative results indicate that the peak temperature of the planetary magnetosheaths are comparable and approach that of the solar corona. A statistical investigation is made of the average temperatures of the magnetosheaths of several planets, and it shows that, although the proton temperatures are several times the electron temperatures, the average plasma temperatures of the magnetosheaths of Earth and Saturn are almost the same as that of the solar corona. This work advances our understanding of the thermal properties of planetary magnetosheaths and also advances research into the formation of plasma sheets. Key Points: A quantitative relationship between the temperature of the steady solar corona and that of the planetary magnetosheaths is shownThe theoretical investigation indicates that planetary subsolar magnetosheaths have approach mean temperaturesA statistical study confirms planetary subsolar magnetosheaths have approach mean temperatures, and these are close to that of the corona [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]