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Highlights The self‐healing process in PCL (polycaprolactone)/epoxy blends is studied in order to optimize the healing process and understand its underlying mechanism. For this purpose, PCL/epoxy blends are prepared with and without multiwall carbon nanotubes (MWCNTs) addition. Three different self‐healing heat‐inducement techniques are used (an oven, Joule effect, and infrared (IR) lamp) as a function of healing time (2, 5, 10, and 15 min) and PCL concentration (5, 10, and 15 wt%). The results obtained demonstrate that the addition of MWCNTs to the polymer matrix in PCL/epoxy blends accelerates the self‐healing process, attributed to an improved heat diffusion in MWCNTs/PCL/epoxy blends. The best self‐healing results were obtained with the highest self‐healing time and concentration of PCL, caused by the higher probability of the crack formation over a PCL reservoir. The most efficient techniques to induce the self‐healing process in PCL/epoxy blends with and without MWCNTs are the conventional oven and the Joule Effect, respectively, being faster the latter method, as it induces a homogeneous internal heating of the material. Moreover, Joule effect can be controlled remotely, while IR radiation is a noncontact technique, which can be applied in situ. The three heating methods are evaluated considering these factors alongside their energy efficiency, establishing a method to choose a specific heating source for similar systems. PCL/epoxy blends reinforced with MWCNTs have been manufactured. Variable heating sources have been analyzed. The influence of the heating source on the self‐healing is studied. Joule constitutes the faster heating for MWCNTs/PCL/epoxy system. [ABSTRACT FROM AUTHOR]

The growth, ion concentrations, powder X‐ray diffraction, thermal properties, and optical spectroscopy of Nd3⁺‐doped Ca₃(BO₃)₂ single crystals are investigated. The Nd3+‐doped Ca₃(BO₃)₂ single crystals with 1.97 at.% Nd3⁺ are successfully grown using the Czochralski (Cz) technique. To address the chemical valence imbalance between Nd3⁺ and Ca2⁺ in the Ca₃(BO₃)₂ crystals, the Na⁺ ions are introduced. The concentrations of Nd3⁺ and Na⁺ ions in the as‐grown crystals are measured using inductively coupled plasma atomic emission spectroscopy (ICP‐AES), yielding concentrations of 1.97 at% (N0 = 1.55 × 1020 cm−3), 1.94 at% (N0 = 1.52 × 1020 cm−3), respectively. The thermal behavior of the Nd3⁺‐doped Ca3(BO3)2 crystals, including thermal expansion coefficients, specific heat, and thermogravimetric and differential thermal analysis (TG‐DTA), is systematically investigated. At room temperature, the polarized absorption spectra, polarized fluorescence spectra, and fluorescence decay lifetimes are measured. Spectral parameters, including polarized absorption and stimulated emission cross‐sections, intensity parameters, transition probabilities, radiative lifetime, and branching ratios are determined using the Judd‐Ofelt (J‐O) theory. The results indicate that Nd3+‐doped Ca3(BO3)2 crystals are promising materials for near‐infrared lasers, offering advantages such as rapid growth, large size, high specific heat, strong emission, and environmental stability. [ABSTRACT FROM AUTHOR]

Syntactic foams are lightweight porous composites obtained by the addition of hollow glass microspheres (HGMs) to a polymer matrix. This work experimentally and numerically investigates the thermal behavior of epoxy‐based syntactic foams with enhanced multifunctionality produced by incorporating microencapsulated phase change materials (PCMs) as functional fillers, providing thermal energy storage and temperature stabilization due to its large latent heat of melting. Foams are fabricated using varying ratios of HGMs (0–40 vol%) and PCM (0–40 vol%) to achieve tuned densities and thermal properties with a total filler content of up to 40 vol%. A one‐dimensional numerical heat transfer model based on the enthalpy method is presented to simulate the thermal behavior of these materials. The model accurately incorporates the specific heat and thermal conductivity of the foam components, as well as the latent heat absorption during PCM melting (up to 68 J/g). The model is experimentally validated by demonstrating good agreement with the measurements of transient temperature profiles during heating tests on the foam samples. The validated tool is then leveraged to model the thermal response of the foams under a sinusoidally varying heat source, similar to the possible real applicative scenarios. These results can help optimize foam compositions balancing energy storage density, heat transfer properties, and structural support for lightweight energy storage systems. Potential applications include high‐efficiency thermal management in battery packs, electronic cooling, solar energy storage, and sustainable temperature‐controlled buildings. Highlights: Foams with 0–40 vol% PCM and 0–40 vol% HGM show up to 68 J/g latent heat.1D numerical model accurately captures thermal conductivity and PCM phase change.Validated model simulates thermal response under sinusoidal heat, optimizing foam composition.Foams act as thermal reservoirs, maintaining up to 5°C lower surface temperatures than epoxy. [ABSTRACT FROM AUTHOR]

In the present article, the creation of a 3D glassy state by gradient thermal history distributed in a monolithic Zr50Cu40Al10 metallic glass using the proposed thermal gradient treatment is discussed. In this thermal method, a rod sample is annealed while sandwiched between BeCu25 jigs and cooled down by tilting contact against a liquid nitrogen‐cooled Cu mesh. This allows one side of the edge of the rod sample to cool down rapidly from the supercooled liquid region and introduce a temperature/cooling rate difference in 3D in a single process. Specific heat measurement, indentation test and evaluation of incubation time for crystallization reveal creation of 3D gradients throughout the whole sample. In the present study, a new technique of creating a 3D heterogeneity of glassy state to the desired distribution by gradient thermal history in metallic glasses will be promoted, and the development of functionally graded monolithic bulk metallic glasses will be encouraged in near future. [ABSTRACT FROM AUTHOR]

Motivated by the notion that the mathematics of gravity can be reproduced from a statistical requirement of maximal entropy, the consequences of introducing an entropic source term in the Einstein–Hilbert action are studied. For a spatially homogeneous cosmological system driven by this entropic source and enveloped by a time‐evolving apparent horizon, a modified version of the second law of thermodynamics is formulated. An explicit differential equation governing the internal entropy profile is found. Using a Hessian matrix analysis of the internal entropy, the author checked the thermodynamic stability for three categorically different toy models describing (i) a ΛCDM$\Lambda{\rm CDM}$ cosmology, (ii) a unified cosmic expanson, and (iii) a non‐singular ekpyrotic bounce. The mathematical condition for a second order phase transition during these evolutions from the divergence of specific heat at constant volume is found. The new‐found condition is purely kinematic and quadratic in nature, relating the deceleration parameter and the jerk parameter that chalks out an interesting curve on the parameter space. This condition is valid even without the entropic source term and may be treated as a general property of any phase transition. [ABSTRACT FROM AUTHOR]

In this paper, the full compressible Navier‐Stokes equations with Cattaneo's heat transfer law or revised Maxwell's law are considered. We present a loss of initial smoothness of smooth solutions within a finite time and give an upper bound of such time. It is not required that the initial data has compact support or contains vacuum in any finite regions. Moreover, the blow‐up result has no restriction about the specific heat ratio. The main approach is motivated by previous studies and constructing a differential inequality. [ABSTRACT FROM AUTHOR]

Forecasting various forms of intermolecular contact and the degree to which the solute and solvent are bonded is highly advantageous when using thermo‐acoustical and volumetric data. Both salts and vitamins are abundant in the human body. A variety of thermo‐acoustical and volumetric properties (viz. velocity [U], density [ρ], adiabatic compressibility [β], surface tension [σ], specific heat ratio [γ], acoustic impedance [Z], relative association [RA], relaxation strength [r], isothermal compressibility [kT], and nonlinearity parameter [B/A]) are investigated in this study. Of the vitamin B3 + H2O and vitamin B3 + H2O + MgCl2 systems have been examined. Through solvation and hydrogen bonding, these characteristics are utilized to describe the interactions between solutes and solvents. Compressibility explains the qualitative intermolecular elastic forces that exist between the molecules of the solvent and the solute. The electrostatic field of ions has formed the basis for discussions on the structural arrangement of molecules in electrolyte solutions. The volumetric and thermoacoustic characteristics exhibit concentration‐dependent changes, suggesting the existence of molecular interactions in both systems. The vitamin B3 molecule shows stronger molecular contact at higher solvent concentrations, although it interacts most molecularly with MgCl2 solvents. This suggests that magnesium molecules are more suited for the attachment of vitamin B3 molecules than are water molecules. [ABSTRACT FROM AUTHOR]

Quasi‐1D chain antiferromagnets with reduced structural dimensionality are a rich playground for investigating novel quantum phenomena. We report the synthesis, crystal structure, and magnetism of two novel quasi‐1D antiferromagnets, β‐PbCu2(TeO3)2Cl2 (I) and PbCu2(TeO3)2Br2 (II). Their magnetic frameworks are constructed via Cu‐based quasi‐1D [Cu(2)O4]∞ zigzag chains with square‐planar [Cu(1)O2X2] (X=Cl or Br) separated among 1D chains. Specific heat measurements show λ peaks at ~9 K and ~19 K for I and II, respectively. Moreover, both broad maximums (χmax=90 K for I and 80 K for II) and small kinks (TN≈9 K for I and 19 K for II) have been observed in magnetic susceptibility measurements of I and II. Bonner–Fisher model fitting, and theoretical analyses were performed to evaluate the magnetic exchange interactions. Our experimental and theoretical results and structure‐properties relationship analysis reveal the coexistence of short‐ and long‐range magnetic ordering from the cooperative effect of 1D [CuO4]∞ chains and [CuO2X2] quadrilateral. [ABSTRACT FROM AUTHOR]

The combustion of traditional pyrotechnics will pose great risks to the environment and human health. Although sulfur‐free pyrotechnics prepared from metals or expired military gunpowder have been used to solve this problem, the high sensitivity of them has resulted in insufficient safety. Therefore, new eco‐friendly and safe pyrotechnics are urgently needed. In this study, we prepared novel metal‐free pyrotechnic compositions for fireworks based on 5‐amino tetrazole. The optimized formulations are proposed by calculation. Particle size effects on thermal stability and kinetics are tested. Then, the sensitivity tests, moisture absorption, and burst temperature test were analyzed and compared. The combustion heat and specific volume were also measured. The Py‐GCMS and PM2.5 were used to clarify the composition of gas products and confirm their environmental‐friendly performance. The findings revealed that the novel pyrotechnics has a small amount of combustion residue, greater safety performance, and less PM2.5 concentration. The novel pyrotechnics could generate 564.9 mL/g clean and non‐toxic gas composed of 93.2% N2, H2O, and CO2 without any NOx or SO2 vapor. The test results suggest that the new pyrotechnics can effectively increase gas production and reduce the content of CO and PM2.5. So, it has great potential in application. [ABSTRACT FROM AUTHOR]

Bushfires pose a significant threat to numerous countries, often causing vast property damages and loss of lives. Efforts to combat and manage these fires heavily rely on predicting the fires' rate of spread and intensity. A significant component of these predictions involves understanding the thermophysical characteristics of vegetative fuels. The accuracy of predictive models (especially physical models) also depends on obtaining precise thermophysical and combustion parameters. This research aims to provide a comprehensive set of thermal degradation and combustion parameters for surface and near‐surface fuel samples collected during prescribed fire experiment conducted in April 2022 in Little Desert National Park, Victoria, Australia. Firstly, fuel properties like fuel height, moisture content, bulk density, fuel load and heat of combustion were meticulously characterized for both surface and near‐surface samples. Then activation energies for degradation reactions were determined using the Flynn–Wall–Ozawa method and for the determination of pre‐exponential factors, in most cases these reactions closely aligned with a Second order model. This was followed by determination of other parameters such as heat of reaction, specific heat and conductivity. It was found that the density, activation energy and heat of combustion did not vary significantly across the six samples under question. The comprehensive set of obtained parameters will likely help to facilitate better predictions in fire propagation modelling. [ABSTRACT FROM AUTHOR]

In the present study, a model was derived for the first time to calculate the nanosize/shape‐dependence of the Grüneisen parameter for freestanding metallic nanomaterials of Cu, Ag, and Au based on thermodynamic‐related parameters, thermal expansion α, bulk modulus B, molar volume V, and specific heat C. Two types of nanomaterial shapes are taken into consideration: spherical and wire. Calculations were performed for the size and shape dependence of α, B, and C by using equations based on the effect of the surface‐to‐volume atomic ratio (N/n), whereas the nanosize dependence of V was calculated according to an equation derived based on the bond length variation for the first time. The calculation results of the related parameters were compared with the available experimental data. The outcomes demonstrated that the suggested models significantly impacted the size down to 15 nm. A strong agreement between theory and experiments demonstrated the suitableness of the proposed model. Accordingly, the Grüneisen parameter was calculated, and outcomes indicate that the Grüneisen parameter decreases as the size decreases. Reducing the lattice structure‐dependent Grüneisen parameter was explained and discussed. [ABSTRACT FROM AUTHOR]

Magnetic nanoparticles (NPs) are efficient heat mediators in induction heating. Originally explored for hyperthermia, their applications have broadened to industrial processes where temperature control is crucial. By adjusting the NP composition or morphology, magnetic characteristics such as Curie temperatures can be tailored, allowing control over maximum heating thresholds. These NPs are, however, usually designed for maximum heating rates at specific magnetic fields. In this work, the synthesis is presented for colloidally stable Co and ZnCo ferrite NPs with customizable maximum heating temperatures, and their combination within micron‐scaled supraparticles (SPs). Maximum induction heating temperatures of ZnCo ferrite NPs are tuned between 150 and 220 °C, while customization of Co ferrite species yields temperatures between 200 and 350 °C. These distinct magnetic properties are exploited in the selective multi‐stage heating of SPs consisting of both species. Here, ZnCo ferrite components heat up to a first temperature plateau at low alternating magnetic fields (AMF), while Co ferrite NPs reach higher temperatures at increased AMF. The precise control of induction heating thresholds through the adaptability of NPs offers a high degree of customizability which makes induction heating particularly attractive for applications requiring sequential or spatial heating, such as catalysis or debonding on demand. [ABSTRACT FROM AUTHOR]

BACKGROUND: Understanding how parasitoids respond to temperature is crucial for improving biological control strategies under the context of global warming. This study examined the suitability of Myzus persicae and its parasitoid Aphidius gifuensis to varying temperature conditions, as well as the stage‐specific response of A. gifuensis to high temperatures. RESULTS: High temperatures had a significant impact on the both M. persicae and A. gifuensis. When exposed to 36°C, M. persicae developed more slowly and produced smaller adults compared to control, regardless of the duration of exposure (2, 4 or 6 h); additionally, the survival rate of M. persicae nymphs sharply decreased under these conditions. Exposure to 36°C for 4 h negatively impacted the development of A. gifuensis. Female parasitoids exposed to 32°C developed into smaller adults, whereas males exposed to all three temperature levels were smaller compared to control group. Female parasitoids exposed to high temperatures, regardless of the specific heat level and duration, exhibited reduced longevity and decreased fecundity. None of the parasitoids exposed to 36°C for 6 h daily developed into adults. Heat treated during early developmental stages (2 and 4 days old) had a greater influence on parasitoid development, whereas heat treatment at 4 and 6 days old had a more significant impact on its fecundity. CONCLUSION: High temperatures not only directly affected the performance of A. gifuensis, but also exerted indirect effects by influencing the quality of the host aphids M. persicae. The deleterious effects of high temperature on larvae can persist into the adult stage, affecting the longevity and reproduction of adults. These findings are important for the utilization of A. gifuensis in the control of M. persicae in warming environments. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The investigation demonstrates the potential of nano zinc oxide as a substitute for conventional rubber grade zinc oxide in the bead filler compound of passenger car tires, aimed at reducing heat generation while preserving mechanical and reinforcement properties. Experimentation showed that introducing nano zinc oxide increased compound viscosity, indicating enhanced filler networking. Cure rates accelerated due to the higher surface area of nano zinc oxides, while the Payne effect indicated improved dispersion levels in experimental compounds. Notably, the variant with four parts per hundred rubber of nano zinc oxide exhibited mechanical properties akin to the control, alongside a 28% reduction in tan δ and improvements in hysteresis loss ratio and specific heat values. Morphological analysis confirmed superior dispersion in experimental compounds. Finite element analysis demonstrated decreased temperature generation and a reduced percentage contribution of the bead filler to overall heat energy in tires, leading to a 3% drop in rolling resistance. These findings suggest that nano zinc oxide can effectively replace conventional zinc oxide, enhancing fuel economy in tires, thereby offering a green initiative to reduce fuel consumption in passenger car radial tires through improved hysteresis at the bead area via bead filler compound modification. Highlights: Nano zinc oxide replaces rubber grade zinc oxide reducing heat generation.Nano zinc oxide improves compound viscosity, enhancing filler networking.Variant with four parts per hundred rubber of nano zinc oxide matches control's mechanics, with 28% lower tan δ.Morphological analysis confirms dispersion, coupled with aggregation.Simulation shows lower temperature generation and 3% less rolling resistance. [ABSTRACT FROM AUTHOR]

In this paper, the effects of hole doping on the magnon specific heat, average number of magnons, magnetization, and Curie temperature (Tc) of the diluted magnetic semiconductor (DMS) (Ga, Mn)As are theoretically studied using Green function formalism and employing a model system Hamiltonian consisting of magnons, holes, and interactions between magnons and holes. The specific heat capacity of magnons and the number of magnons are found to decrease in the presence of holes and hole–magnon interaction strength, whereas magnetization and Curie temperature (Tc) increase. Our study also reveals that at a constant finite temperature, an increased number of holes lead to a significant increase in magnetization. However, at T = 0, the ground state magnetization value does not exhibit any change with increased free holes and hole–magnon interaction strength. The increased magnetization resulting from doping with holes or electron excitations in this study may present an opportunity to utilize the system under consideration for spintronics purposes at room temperature. [ABSTRACT FROM AUTHOR]

Ultra‐broadband photodetectors based on semimetal crystals have recently become popular because of their gapless band structures. In particular, semimetal crystals have large carrier mobility or high Seebeck coefficient; this almost eliminates the possibility of using semimetal crystals as photodetectors. In addition, a larger temperature gradient can cause photocurrent generation based on the photothermoelectric effect. Surprisingly, the TaTe2 crystal has a huge absorption coefficient (≈104 cm−1), a minimal specific heat (≈0.172 J g−1 K−1), and a low thermal conductivity (0.3 W m−1 K−1), which is beneficial for generating a high photothermal conversion efficiency of 30.2%, despite its small Seebeck coefficient, and achieving a large temperature gradient occurs for the heat generated by external illumination. Herein, the possibility of photoresponse based on the TaTe2 detector is explored, which has a low carrier mobility (≈10 cm2 V−1 s−1) and a small Seebeck coefficient (≈7.1 µV K−1). The self‐powered TaTe2 photodetector can also provide a competitive photoresponse range from 355 to 2715 nm and exhibit a maximum responsivity of 1.1 mA W−1 with a detectivity of 4.7 × 108 Jones at 455 nm. This study provides a new design scheme and operating mechanism for semimetal photodetectors and enriches semimetal crystal photodetectors. [ABSTRACT FROM AUTHOR]

Phase change materials (PCMs) can absorb, store, and release substantial latent heat within a specific temperature range during phase transition and have gained huge attention due to environmental concerns and energy crises. However, PCMs have a significant downside in energy storage due to their relatively lower thermal conductivity, leading to inadequate heat transfer (HT) performance. The foremost aim of the research is to synthesize an eco‐friendly coconut shell biochar (CSB) dispersed with organic A46 PCM in the temperature range of 44°C to 46°C to form a green nanocomposite. A two‐step approach is adopted to formulate the nanocomposites with different weight concentrations (0.2% and 0.8%) of green CSB particles. The developed nanocomposite's thermal conductivity and chemical stability were examined using a thermal properties analyzer and a Fourier transforms infrared spectrometer. The developed biochar composites have excellent thermal conductivity (0.39 W/m K) compared with base PCM (0.22 W/m K). Also, the developed nanocomposites were physically mixed together; there were no additional functional groups formed compared to pristine PCM, and the prepared materials were composite. Furthermore, a numerical analysis was performed using two‐dimensional energy modeling software to ascertain the HT rate of A46 composites. These thermally energized green nanocomposites show great promise for thermal energy storage and thermal management applications like battery thermal management, photovoltaic thermal systems, desalination systems, electronic cooling, building applications, and textiles. [ABSTRACT FROM AUTHOR]

The use of solid tires in demanding industrial applications, subjected to substantial mechanical loads, poses significant challenges due to heat generation from hysteresis and tread friction. Managing this heat is crucial to mitigate the risk of tire blowouts and layer separation. This research investigates the impact of introducing vein graphite powder, varying in particle size, into a commercially used solid tire compound, both experimentally and computationally. The research findings presented in this paper reveal substantial changes in thermal conductivity, specific heat capacity, rate constant, induction time, and the order of reaction in solid tires. Contemporary industry trends involve predictive methods for monitoring the curing process in tire manufacturing. A tire curing simulation model based on finite (FE) element analysis is developed. FE modeling is favored due to its accuracy and adaptability, especially when dealing with the intricate geometry and multi‐layered, multi‐compound structure of tires. The complex interplay between heat transfer and curing processes is effectively addressed using user subroutines (UMATHT) in commercial FE software like ABAQUS. In this analysis, thermal conductivity, heat capacity, order of reaction, rate constant, and induction time of the commercial tire compound are considered as temperature‐dependent variables. The computational model not only demonstrates its potential to significantly enhance the efficiency and quality of tire manufacturing processes but also contributes to a deeper understanding of the curing behavior of graphite powder‐based solid tire compounds. Consequently, it provides a valuable tool for optimizing tire manufacturing procedures and ensuring the safe and reliable performance of solid tires under demanding operational conditions. This research bridges the gap between the traditional commercial tire compound and the use of vein graphite powder in tire manufacturing and advanced computational methods, facilitating improvements in tire quality and safety. [ABSTRACT FROM AUTHOR]

Investigating the multiferroic properties of Cu2OCl2$\left(\text{Cu}\right)_{2} \left(\text{OCl}\right)_{2}$, their temperature and magnetic‐field dependencies around the magnetic and ferroelectric phase transition temperatures TN$T_{N}$ and TE$T_{E}$ are analyzed using a microscopic model and Green's function technique. Near the Neel temperature TN$T_{N}$, a kink in the specific heat Cp(T)$C_{p} \left(\right. T \left.\right)$ and also in the phonon energy ω(T)$\omega \left(\right. T \left.\right)$ and damping γ(T)$\gamma \left(\right. T \left.\right)$ due to strong anharmonic spin–phonon interaction is observed. The kink in Cp(T)$C_{p} \left(\right. T \left.\right)$ disappears with increasing magnetic field h. The polarization P(T)$P \left(\right. T \left.\right)$ shows also a small anomaly at TN$T_{N}$ and decreases with increasing magnetic field h. This behavior strongly suggests that Cu2OCl2$\left(\text{Cu}\right)_{2} \left(\text{OCl}\right)_{2}$ exhibits multiferroic characteristics. A kink at TN$T_{N}$ can be seen in the real part of the dielectric constant ε′(T)$\left(\epsilon\right)^{&aposx;} \left(\right. T \left.\right)$, too. It should be noted that ε′$\left(\epsilon\right)^{&aposx;}$ demonstrates a significant increase with increasing field strength h below TN$T_{N}$, which is a pronounced magneto‐dielectric effect. These findings qualitatively agree with the experimental data. [ABSTRACT FROM AUTHOR]

We show that powder pressed specimens of nickel can be sintered to 99.96% density by injecting electrical current, without the use of a furnace. Full sintering could be accomplished in 10 to 52 s by changing the current rate from 5 to 1 A/s. In all instances, the samples sintered abruptly at a current density of ∼20 A mm−2. The grain size of the sintered samples was somewhat larger than the nickel powder particle size (∼60 μm vs. 40 μm). Tensile testing yielded a yield strength of 98 MPa, ultimate tensile stress of 323 MPa, and ductility of ∼17%. Four in‐operando measurements are reported: (i) sintering, (ii) the change in resistance with current density, (iii) the temperature, and (iv) electroluminescence. The change in resistance during flash sintering exhibited a high peak followed by a steep decline in resistance; the transient is attributed to the breakdown of particle–particle interface resistance. The same cycle repeated with the flash‐sintered, dense sample, did not show the spike, and gave reproducible results. The resistance data for these latter cycles, when viewed as a function of temperature exhibited sigmoidal behavior: initially lower, and then higher than the literature values. This unusual behavior reflects the influence of defects generated during flash. We have also measured the endothermic enthalpy, expressed by the difference between the in situ input electrical energy and the radiation, convection, and specific heat losses. Dividing by the formation energy of Frenkel pairs yields the concentration of defects, estimated to be 0.3–0.4 mol %. These concentrations are far above thermal equilibrium; it is concluded that flash of metals is a far from equilibrium phenomenon. [ABSTRACT FROM AUTHOR]

Investigating the multiferroic properties of Cu2OCl2$\left(\text{Cu}\right)_{2} \left(\text{OCl}\right)_{2}$, their temperature and magnetic‐field dependencies around the magnetic and ferroelectric phase transition temperatures TN$T_{N}$ and TE$T_{E}$ are analyzed using a microscopic model and Green's function technique. Near the Neel temperature TN$T_{N}$, a kink in the specific heat Cp(T)$C_{p} \left(\right. T \left.\right)$ and also in the phonon energy ω(T)$\omega \left(\right. T \left.\right)$ and damping γ(T)$\gamma \left(\right. T \left.\right)$ due to strong anharmonic spin–phonon interaction is observed. The kink in Cp(T)$C_{p} \left(\right. T \left.\right)$ disappears with increasing magnetic field h. The polarization P(T)$P \left(\right. T \left.\right)$ shows also a small anomaly at TN$T_{N}$ and decreases with increasing magnetic field h. This behavior strongly suggests that Cu2OCl2$\left(\text{Cu}\right)_{2} \left(\text{OCl}\right)_{2}$ exhibits multiferroic characteristics. A kink at TN$T_{N}$ can be seen in the real part of the dielectric constant ε′(T)$\left(\epsilon\right)^{&aposx;} \left(\right. T \left.\right)$, too. It should be noted that ε′$\left(\epsilon\right)^{&aposx;}$ demonstrates a significant increase with increasing field strength h below TN$T_{N}$, which is a pronounced magneto‐dielectric effect. These findings qualitatively agree with the experimental data. [ABSTRACT FROM AUTHOR]

The onset of thermal convection in an incompressible Oldroydian fluid‐saturating porous media is examined to study the combined impact of uniform rotation and temperature‐dependent viscosity. A characteristic equation from the basic hydrodynamic equations governing the Brinkman–Oldroyd model is derived using linear stability theory and modified Boussinesq approximation. For various combinations of stress‐free and slip‐free boundaries, the expressions for the Darcy–Rayleigh numbers for both non‐oscillatory as well as oscillatory convection with linear and exponential temperature‐dependent viscosity are derived, using the "weighted residual method." The effects of rotation, variable viscosity parameter, strain retardation and stress relaxation time parameters and other fluid parameters on non‐oscillatory and oscillatory convection are investigated numerically and the results are presented graphically. From the analysis, it is found that overstability is the preferred mode of onset of convection. The rotation, the coefficient of specific heat variations (due to temperature variation), and the strain retardation time have a stabilizing influence on the stability of the system, whereas the stress relaxation imparts a destabilizing effect. Additionally, it is noticed that the variable viscosity parameter and Brinkman‐Darcy number stabilize the system for each set of boundary conditions. [ABSTRACT FROM AUTHOR]

The multiple wavelength diode laser (MWDL) is a sophisticated device designed to target deeper skin layers by emitting various wavelengths. Its unique feature is the ability to deliver heat to specific depths within the tissue using different wavelengths while simultaneously cooling the skin surface. Recent research by Choi et al. suggests that wavelengths of 755 and 810 nm can induce carbonization in hair follicles, while the 1064 nm wavelength penetrates deeper into tissues. MWDL has been proposed for fat redistribution in aging, but concerns have been raised regarding ocular safety and potential tissue damage, particularly when used near the eyes. Studies have shown ocular injuries during cosmetic laser procedures, emphasizing the need for robust ocular protection and safety protocols. Additionally, there are reports of internal ischemic necrosis and burns, highlighting the importance of precise energy settings and parameter management. While MWDL shows promise, further research and comprehensive guidelines are needed to ensure safe and effective usage in clinical practice. [ABSTRACT FROM AUTHOR]

This study has performed molecular modeling, vibrational dynamics, and thermodynamics of tyramine neurotransmitter and its monohydrate cluster in gas phase. All theoretical calculations for tyramine and its monohydrate cluster are performed at DFT/B3LYP/6‐31++G(d,p) level to optimize the electronic structures and calculation of vibrational frequencies. Most of the vibrational frequencies have been found in good agreement with the experimentally reported IR and Raman frequencies. However, some have been modified. The presence of water monomer decreased highest molecular orbital–lowest unoccupied molecular orbital (HOMO–LUMO) energy gap of tyramine by 0.07 eV. Themodynamics calculations reveal that thermal energy and specific heats in both the tyramine and its monohydrate clusters are predominantly contributed by vibrational motions while entropy shows only 28% and 26% vibrational contribution in tyramine and its monohydrate cluster, respectively. [ABSTRACT FROM AUTHOR]

Based on the new thermodynamic theory, a new model was suggested to calculate the specific heat capacities of monoatomic gas, He, and diatomic gas, O2. The theory suggests a portion of gas molecules with the highest kinetic energy affords the heat exchange to sustain the state equilibrium by inelastically colliding and liquefying on the container walls, whereas the rest elastically colliding with walls creates pressure. Accordingly, a general equation of specific heat capacity is established on the density of liquid and gas. Given ∂lnVL∂lnTP ${{\left[{{\partial ln{V}_{L}}\over{\partial lnT}}\right]}_{P}}$ at isobar and ∂P∂TV ${{\left[{{\partial P}\over{\partial T}}\right]}_{V}}$ at isochore, Cp and Cv at any temperature can be calculated with the densities of gas and liquid (or solid). Employing the available data of He and O2 issued by NIST, Cps, and Cvs are calculated. The results fit the reference data well. [ABSTRACT FROM AUTHOR]

We report the magnetic and optical properties of Fe2(HPO3)3 ⋅ 4H2O. By combined magnetic susceptibility and specific heat measurements, we find two antiferromagnetic (AFM) transitions (TN1=9 K, TN2=5 K) which originate from the AFM exchange interactions mediated by the (HPO3)2− anions. Compared with the non‐hydrated compound Fe2(HPO3)3, the magnetic interaction strength and ordering temperature of Fe2(HPO3)3 ⋅ 4H2O are both reduced by a factor of ~2. Through density functional theory (DFT) analysis we find almost degenerate AFM states in Fe2(HPO3)3 ⋅ 4H2O which are close in energy. The competition of these AFM states might lead to the two successive AFM phase transitions at low temperature. The low ordering temperature as well as competing AFM states both imply frustrated magnetism in Fe2(HPO3)3 ⋅ 4H2O, probably originating from the complex competing AFM interactions. The optical properties of Fe2(HPO3)3 ⋅ 4H2O are also investigated by photoluminescence and infrared spectroscopies. [ABSTRACT FROM AUTHOR]

The main objective of the review was to investigate the ferromagnetism of diluted magnetic semiconductors made of Mn‐doped GaAs. Manganese‐doped gallium arsenide has recently become an important field of research because of its potential applications in the fields of spintronics and magnetic devices. The magnetic moment caused by adding manganese to the GaAs crystal structure causes a low‐temperature ferromagnetic behavior. The main factor that affects the ferromagnetic properties of Mn‐doped gallium arsenic is manganese concentration. Understanding the relationship between Mn concentration and magnetic properties is important for material optimization in specific applications. It was found that Mn‐doped GaAs exhibit paramagnetic behavior below a specific critical concentration. However, the substance is transformed into a ferromagnetic state over the maximum concentration. The Curie temperature is an important additional factor influencing the ferromagnetic properties of Mn‐doped GaAs. The temperature at which a material ceases to exhibit ferromagnetic behavior is known as the Curie temperature. The Curie temperature of a material depends on its Mn concentration, thin film thickness, and degree of disturbance. A reduction in magnetic resistance increases the concentration of Mn‐treated gallium arsenic and increases its rate as it reaches its maximum value. High Curie temperatures are the result of stronger magnetic interactions resulting from higher manganese concentrations. The specific heat capacity of Mn‐doped gallium arsenide is influenced by its magnetic and structural contribution. [ABSTRACT FROM AUTHOR]

Channel catfish fillets with different microwave heating times were evaluated by differential scanning calorimetry and low‐field nuclear magnetic resonance to build suitable modeling of apparent specific heat capacity (Cp) ranging from −60 to 90°C (except the obvious phase change region from −20 to 20°C). The content of bound water (Wb), immobilized water (Wi), and free water (Wf) were weighted and calculated. According to non‐linear fitting of experimental data, the obtained empirical equation of Cp, temperature (T), Wb, Wi, and Wf of samples was:Cp=a+bwb+cwi+dwf+eT/1+fwb+gwi+hwf$$ {C}_{\mathrm{p}}=\left(a+b{w}_{\mathrm{b}}+c{w}_{\mathrm{i}}+d{w}_{\mathrm{f}}+ eT\right)/\left(1+f{w}_{\mathrm{b}}+g{w}_{\mathrm{i}}+h{w}_{\mathrm{f}}\right) $$. The equation was in good correlation (R2 > 0.95) with the experiment data and could provide a basis for improvement of processing parameters. [ABSTRACT FROM AUTHOR]

Desalination can provide additional water resources in water‐stressed zones and also in zones suffering from water pollution or insufficient/overexploited groundwater. This study carried out the energy and exergy assessments of a multi‐effect desalination unit driven by a gas turbine based on the specific exergy cost (SPECO) approach. The chemical exergies of brine and seawater are explicitly considered (most studies consider the same specific heat for input seawater and output brine). In addition, the enthalpy of each flow of the desalination unit is considered according to its salt concentration (results are then compared to the constant specific heat model). The highest exergy rates of fuel and product are obtained at the combustion chamber, and its exergy efficiency is 67.83%. The lowest exergy efficiencies were obtained at the condenser, followed by the first effect of the desalination unit, and the heat recovery steam generator. The overall exergy efficiency of the multi‐effect distillation unit is 21.49%. Regarding exergy destruction, as expected, the highest rate was obtained at the combustion chamber, which contributed with 41% to the overall exergy destruction, followed by the regenerator and heat recovery steam generator, with contributions of 16% and 11%, respectively, to overall exergy destruction. [ABSTRACT FROM AUTHOR]

Engineering and flow properties of banana seed powder as a function of moisture content are important for processing, handling, packaging, and transport processes. The bulk density, tapped density, and porosity increased from 377.37 to 427.36 kg m-3, 622.08 to 746.33 kg m-3, and 38.99-43.74%, respectively, within the increasing moisture content range. The Hausner ratio (Hr) and Carr's compressibility index (CI) significantly (p < 0.05) increased with an increase in moisture content (6.16-19.56% db) of banana seed powder, whereas HR fell in the range of 1.4-2.0, indicating cohesive characteristics of banana seed powder. The angle of repose, angle of spatula, and angle of fall exhibited a linear increase, ranging from 40.6° to 49°, 33.4° to 39.4°, and 35.6° to 42.6°, respectively, with increasing moisture content. The static coefficient of friction was found to be highest for aluminium and glass surfaces and least for stainless steel. The water activity and swelling power of banana seed powder showed a significant increase, while the solubility and oil absorption capacity exhibited a significant decrease within the range of increasing moisture content. The thermal characteristics of wild banana seed powder, such as thermal conductivity (0.16 to 0.20 Wm−1 K−1) and volumetric specific heat (0.58 to 0.99 MJm−3 K−1), demonstrated an increasing trend as the moisture content increased. However, the thermal diffusivity showed a decrease from 0.31 to 0.19 (×10−6 m2s−1) with the increase in moisture content. [ABSTRACT FROM AUTHOR]

A comprehensive study of magnetotransport and field‐dependent specific heat of FeTe0.58Se0.42 single crystals synthesized using the self‐flux method is reported. The transport measurement reveals the presence of Fermi liquid behavior in the normal state resistivity of the single crystals. Furthermore, the grown single crystals exhibit anisotropy and demonstrate a high value of upper critical magnetic field (HC2). The magnetoresistance exhibits a linear behavior as the magnetic field increases, suggesting the possible presence of a Dirac‐cone state. Anisotropy is also observed in magnetoresistance near the superconducting transition temperature (TC). The sign reversal of the Hall coefficient and the violation of Kohler's rules are observed, which provide evidence of the presence of multiband effects in FeTe0.58Se0.42 single crystals. Specific heat measurements confirm the bulk superconductivity in the grown single crystals. Additionally, the specific heat jump ΔC(TC)/TC is estimated, which is approximately equal to 26 mJ mol−1 K−2. The magnetic field‐dependent specific heat also suggests multiband superconductivity and offers insights into the upper critical field. Furthermore, the electronic specific heat (Cel) is best fitted with a two‐band model. Moreover, the field‐dependent residual Sommerfeld coefficient γ(H) gives information about the superconducting pairing symmetry. [ABSTRACT FROM AUTHOR]

The current paper has the objective of exploring the thermophysical properties (TPPs) of single walled carbon nanotube (SWCNT) nanofluids (NFs) for heat transfer applications. The effect of dispersing the nanotubes in conventional heat transfer fluids (HTFs) has been investigated. Carbon nanotubes (CNTs) have exceptionally high thermal conductivities. Using the effective medium theory, density, specific heat, thermal conductivity, and viscosity has been evaluated as functions of volume fractions. The base fluids considered in this work are water, ethylene glycol, engine oil, and kerosene oil as these are the commonly used HTFs for industrial applications. Theoretical predictions from this study show an increase in density, thermal conductivity, and viscosity with volume fraction while there is a decrease in specific heat with volume fraction. The effect of the aspect ratio (AR) of CNTs on the thermal conductivity of NF is also investigated. For low volume fractions of SWCNT, the thermal conductivity has been found to increase with AR. Further, this study has been extended for a real‐world application of heat transfer using SWCNT. In this paper, a numerical investigation of heat transfer in a square enclosure with differentially heated vertical walls, filled with SWCNT‐water NF under natural convection is carried out. Due to low concentrations of SWCNT in water, single phase flow is assumed. Velocity and temperature distributions are obtained as solutions to the energy and Navier–Stoke's equations. A comparison of the temperature and velocity profile has been represented by simulating the system over a range of Rayleigh numbers. [ABSTRACT FROM AUTHOR]

Among organic phase‐change materials (PCM), paraffin is commonly used, but it is not environmentally friendly due to its petrochemical origin. For efficient utilization of solar or thermal energy, new PCM are needed, or it is necessary to improve the thermal properties of existing materials. Therefore, the utilization of renewable alternatives such as lamb's tail fat as a latent heat storage material is of particular importance for the evaluation of bio‐based waste oils. In this study, new PCM were developed by using different concentrations of cyclophosphazene derivatives as an additive to the starting lamb tail fat (LTF) material. According to the results, doping the LTF with 1% and 2% hexa(N,N‐dibutyl‐4‐aminophenoxy)cyclotriphosphazene (HBACP) the heat of fusion is significantly improved, while the 1% hexa(2‐ethylhexyloxy)cyclotriphosphazene (HEHCP) doping decreased the heat of fusion. In a comparison of various doped PCM, it was found that the tail fat doped with 1% HBACP had a heat of fusion of 166.6 kJ/kg, but a lower specific heat capacity and thermal conductivity than that doped with 2% HBACP. On the other hand, 1% HEHCP had the lowest thermal conductivity but a higher specific heat capacity than 1% HBACP. In addition, it was found that the PCM developed by incorporating HBACP could be operated as a cooling fluid for photovoltaic modules or as a working fluid in concentrated solar energy systems due to the higher heat of fusion value of 1% HBACP and the higher specific heat capacity of 2% HBACP, which consists of lamb's tail fat. [ABSTRACT FROM AUTHOR]

The thermal properties of Octadecane vary due to the addition of copper oxide (CuO) nanoparticles. The synthesis of two nano‐enhanced phase change material (NEPCM) required the implementation of the two‐step method, using Octadecane as the base phase change material and CuO nanoparticles at 2.5 and 5.0 wt%. The experimental characterization determined the specific heat capacity, and thermal conductivity of the NEPCMs solid phase, including phase change enthalpy and temperature. These experimental results were then utilized for computational simulation of the thermal charging (solidification) and discharging (melting) processes of NEPCMs within a spherical enclosure, employing the ANSYS/Fluent software. The incorporation of CuO nanoparticles led to an increase in thermal conductivity while causing a decrease in specific heat capacity, enthalpy, and phase change temperature of Octadecane. The computational results revealed a reduction in the melting period and an improvement in the solidification of both NEPCMs. In terms of melting, the convective heat transfer coefficient increased by approximately 27.4% and 3.2% for the NEPCM at 2.5 and 5.0 wt% CuO, respectively. During the solidification process, the overall heat transfer coefficient experienced a significant increase of 43.8% and 59.8% for the NEPCM at 2.5 and 5.0 wt%, respectively. [ABSTRACT FROM AUTHOR]

Magnetic refrigeration technology based on Gd‐based paramagnets is expected to be applied to refrigeration in extremely low temperatures, thereby reducing the consumption of liquid helium. Here, we obtained a compound, Gd3TeBO9 with high Gd3+ concentration through element substitution. The Gd3+ concentration in this compound is as high as 2.4×1024 ions/kg, which is 33 % higher than the commercial Gd3Ga5O12 (GGG), and further magnetic tests show that Gd3TeBO9 has a large magnetic entropy change (57.44 J/(kg K) and 408 mJ/(cm3 K) at 2.6 K and 7 T), which is 1.5 times that of GGG, implying the possibility of its further development as an potential magnetocaloric material. [ABSTRACT FROM AUTHOR]

N‐type ZrNiSn‐based alloys reach a record thermoelectric figure of merit zT ≈1.2 by increasing the carrier concentration to 4–5 × 1020 cm−3. In this work, It is reported that a comparable zT can also be realized in trace Ru‐doped ZrNiSn‐based alloy at even lower temperature by decreasing the carrier concentration. Compared to the previously reported Co doping, the doping of Ru results in a more effective reduction in carrier concentration, and thus higher Seebeck coefficient, lower electronic thermal conductivity, and enhanced thermoelectric performance. The electronic specific heat coefficient of the ZrNi1‐xRuxSn sample remains constant with increasing Ru content, indicating no obvious change in the density of states effective mass. Theoretical calculations show that the doping of Ru has negligible effect on the bottom of conduction band. The lattice thermal conductivity is further reduced by alloying Ti and Hf at the Zr site, and the bipolar diffusion is suppressed by doping of 0.5 at.% Sb. As a result, Ti0.25Zr0.5Hf0.25Ni0.99Ru0.01Sn0.995Sb0.005 reaches not only a zT value of 1.1 at 773 K but also a record average zT value of 0.8 in 300 to 873 K, demonstrating the effectiveness of trace Ru doping on boosting the thermoelectric performance of ZrNiSn‐based alloys. [ABSTRACT FROM AUTHOR]

Nanofluids are thermoelectric substance with a greater thermal transmission effectiveness than traditional thermal fluids. Nanofluid's specific heat capacity (SHC) is a crucial thermophysical parameter since it controls the fluid's heat transfer coefficient. Surprisingly few research investigations have been done on the prognostic modelling of the specific heat capacity of fusion nanofluids, despite the fact that numerous experiments have been conducted on the heat transfer capacitance of blended nanofluids. This study focuses on the use of algorithms based on machine learning procedures (MLP) to estimate the SHC of blended nanofluids. Numerous numbers of hybrid nanofluids are investigated in this investigation. Total of 984 samples of hybrid nanofluids for specific heat capacity has been collected from nine experimental research papers. Various MLP techniques were utilized in this analysis, including extreme boost gradient boost regression (XGB), support vector regression augmented with a genetic algorithm (support vector regression [SVR]‐genetic algorithm [GA]), grid search optimized based gradient boost regression algorithm (GBR) (GBR‐GSO), and voting ensemble procedure (VE). The obtained correlation coefficients of the SVR‐GA, XGB, VE and GBR‐GSO models for the testing dataset are 98.43%, 96.29%, 94.4% and 96.55% respectively. The SVR‐GA model showed a better predictive accuracy relative to other ML models. This SVR‐GA anticipated model could be used for quick and reliable prediction of the SHC of blended nanofluids which reduces the burden associated with experimental measurement possible future work includes applying a machine‐learning strategy to the problem of determining the diffusivity of hybrid nanofluids. [ABSTRACT FROM AUTHOR]

Cs2Mo2O7 ⋅ CsI is obtained as a member of the series Cs2Mo2O7 ⋅ CsX with X=Cl, Br, and I from the synthesis of Cs2MoO4 with MoO3 and CsX. At room temperature, the compounds crystallize in the space group P63/mmc with the dimolybdate, [Mo2O7]2−, in a linear and eclipsed conformation. Low temperature Raman spectroscopy and low temperature X‐ray diffraction were used to investigate the effect of the ∞2{CsX} ${_\infty ^2 \{ {\rm{CsX}}\} }$ hetero‐honeycomb lattice on the bridging angle of the dimolybdate. For X=Cl, a phase transition occurs below 150 K (P63/mmc → Cmcm). The phase transition relates to a lock‐in that involves bending of the (Mo−O−Mo) bridge. For the Pearson softer iodide compound, no phase transition is observed down to 4 K; thus, the linear configuration remains stable. Specific heat data and their evaluation in terms of phonon contributions are given. [ABSTRACT FROM AUTHOR]

An improved model for multistage flash (MSF) structures is developed and used to assess the performance of a novel MSF configuration, termed as MSF reversal (RV‐MSF) and consisting of reversing the brine circulation stream. The improved model determines the temperature distribution within the stages using heat balance equations while the simplified one, which is commonly used, is based on pre‐specified, constant, and equal temperature distribution throughout the stages. The performance of the RV‐MSF is investigated and compared with conventional MSF once‐through (OT‐MSF) with and without brine mixing using simplified and full models. It is found that the simplified model overestimates the required heat transfer specific area for both MSF configurations. Moreover, it underestimates the cooling water and energy requirements for the reversal configuration. Hence, the simplified model may be good for quick analysis but leads to inaccurate design specifications and economic analysis. When brine mixing is utilized, the simplified model still provides erroneous estimates of the heat transfer area for both MSF configurations. Nevertheless, for OT‐MSF structure, the simple model can provide comparable predictions with that of the improved model in terms of recovery ratio, performance ratio, and specific energy consumption. For the RV‐MSF structure, a mismatch in the two model predictions of surface area, cooling water, and energy requirements is observed. Furthermore, the temperature drop in the cooling system for RV‐MSF has a significant influence on the specific surface area and cooling water requirements especially at low values. The different behaviour of the simplified model between the OT‐MSF and RV‐MSF configurations is attributed to the fact that brine recycling does not affect the feed temperature or the temperature distribution in the system. [ABSTRACT FROM AUTHOR]

The post‐harvesting procedures, such as grading, washing, transporting, and packaging can be made better with understanding of the attributes of agricultural commodities. The paper aims to estimate the asparagus roots' thermal, physical, and biochemical characteristics. The asparagus was found to vary in the range of 6.26–13.60 cm long. The width and thickness of the root were almost the same and ranged from.69 to 1.10 cm. The bulk density, true density, and porosity ranged from.561 to.771 g/cm3, 1.418 to 2.124 g cm3, and 60.437 to 63.689%, respectively. The water activity of the roots was observed to be in the range of.797–.828. The color characteristics of asparagus roots were found to be L* = 45.46, a* = 6.94, and b* = 23.23. The obtained values of the following thermal variables were: thermal diffusivity = 8.176 × 10−8 m2/s, thermal conductivity =.493 W/m °C, specific heat = 3.424 kJ/kg °C, and latent heat = 23442.74 J/kg. The total phenolic and tannin content in the roots were observed to be 24.41 ±.09 mg of gallic acid equivalent (GAE)/g and 1.73 ±.06 mg of tannic acid equivalent (TAE)/g, respectively. The flavonoid content in the roots was 10.33 ±.04 mg of quercetin equivalent (QE)/g. The root samples were found to be a high capacity to scavenge free radicals and also contain phytochemical components that may prove valuable in future research to combat oxidative stress. The findings of this study will also be advantageous in developing handling and processing equipment for the industrial production of asparagus root products. Practical applications: Asparagus is a medicinal plant which is now widely used in food processing to produce the fortified‐functional food products because of its high nutritional and medicinal properties. The grading, sorting, conveying, pulping, processing, and handling equipment for various horticultural goods, including asparagus, are designed using machine designing parameters, which are vital and essential parameters. The size and shape of all agricultural commodities varies. The slight modifications to size and form could reduce the effectiveness of numerous procedures and their associated machinery. Therefore, the knowledge about these engineering and biochemical properties of asparagus will inspire researchers to create and upgrade machinery used for grading, sorting, conveying, pulping, and processing. [ABSTRACT FROM AUTHOR]

X‐ray powder diffraction, electrical resistivity, magnetization, and thermodynamic measurements are conducted to investigate the structure and superconducting properties of TiHfNbTaMo, a novel high‐entropy alloy possessing a valence electron count (VEC) of 4.8. The TiHfNbTaMo HEA is discovered to have a body‐centered cubic structure (space group Im3¯m$Im\bar{3}m$) with lattice parameters a = 3.445 (1) Å and a microscopically homogeneous distribution of the constituent elements. This material shows type‐II superconductivity with Tc = 3.42 K, lower critical field µ0Hc1(0) = 22.8 mT, and upper critical field µ0Hc2(0) = 3.95 T. Low‐temperature specific heat measurements show that the alloy is a conventional s‐wave type with a moderately coupled superconductor. First‐principles calculations show that the density of states (DOS) of the TiHfNbTaMo alloy is dominated by hybrid d orbitals of these five metal elements. Additionally, the TiHfNbTaMo HEA exhibits three van Hove singularities. Furthermore, the VEC and the composition of the elements (especially the Nb elemental content) affect the Tc of the bcc‐type HEA. [ABSTRACT FROM AUTHOR]

Background and Aims: The influence of temperature on various aspects of daily life is often underestimated, and its effects on mental health are not widely recognized. Understanding and addressing the relationship between temperature and mental well‐being is crucial in the context of climate change and rising global temperatures. This perspective aimed to investigate the effects of high temperatures on mental health and identify proactive strategies to mitigate these effects. Methods: This perspective adopted a twofold approach, including a comprehensive literature review and socioecological framework. The literature review involved extensive searches across Google Scholar, PubMed, and Scopus to identify relevant, peer‐reviewed articles, and reports from diverse disciplines. Results: The perspective emphasized the significance of recognizing heat stress and its consequences on mental well‐being. Chronic heat stress can lead to increased stress, anxiety, and cognitive impairment. Vulnerable populations include, the very young, older adults, and individuals with pre‐existing mental health conditions. Socioeconomic factors can further exacerbate vulnerability, highlighting the need for tailored strategies to manage mental health challenges during high temperatures. Additionally, the article identified and discussed proactive coping strategies to minimize both the psychological and physical impacts of heat stress. Mindfulness, stress management techniques, and therapy are suggested as effective means for individuals to manage psychological distress. Conclusion: Implementing preventive measures are essential steps in promoting mental wellness in high temperatures. Proactive strategies by addressing the physiological and psychological effects of heat and considering the specific needs of vulnerable populations can help individuals and communities navigate the challenges posed by rising temperatures and promote resilience and preserve their mental well‐being. [ABSTRACT FROM AUTHOR]

Black holes (BHs) convey information about different matter‐energy distributions in their immediate environment, as they bear the imprints of the intrinsic spacetime geometry and exotic surrounding matter. In this regard, exact spherically symmetric regular black hole (BH) solutions supported by two phenomenological distributions of dark matter galactic halos in Eintein‐Gauss‐Bonnet gravity are explored. Analytical solutions for the metric and the corresponding thermodynamic properties, including heat capacity (C+$C_+$), Gibbs' free energy (F+$F_+$), and Hawking temperature (T+$T_+$) associated with the BH's horizon radius and quasinormal modes (QNMs) are found. The specific heat is investigated, and it is discovered that a Hawking‐Page phase transition with divergent C+$C_+$ occurred at a critical radius, r+c$r_+^c$. Consequently, the authors have regular BHs with Cauchy and event horizons, and evaporation results in thermodynamically stable double‐horizon BH remnants with zero temperatures. The QNMs of the scalar field perturbations on the regular background of the BHs are then discussed comprehensively. Black holes (BHs) convey information about different matter‐energy distributions in their immediate environment, as they bear the imprints of the intrinsic spacetime geometry and exotic surrounding matter. In this regard, exact spherically symmetric regular black hole (BH) solutions supported by two phenomenological distributions of dark matter galactic halos in Eintein‐Gauss‐Bonnet gravity are explored. Analytical solutions for the metric and the corresponding thermodynamic properties, including heat capacity (C+$C_+$), Gibbs' free energy (F+$F_+$), and Hawking temperature (T+$T_+$) associated with the BH's horizon radius and quasinormal modes (QNMs) are found. The specific heat is investigated, and it is discovered that a Hawking‐Page phase transition with divergent C+$C_+$ occurred at a critical radius, r+c$r_+^c$. Consequently, the authors have regular BHs with Cauchy and event horizons, and evaporation results in thermodynamically stable double‐horizon BH remnants with zero temperatures. The QNMs of the scalar field perturbations on the regular background of the BHs are then discussed comprehensively. [ABSTRACT FROM AUTHOR]

5at.% Yb:Lu2O3 transparent ceramics were fabricated successfully by vacuum sintering along with hot isostatic pressing posttreatment from the nanopowders. The influences of calcination temperature on morphology and microstructures of powders and ceramics were studied systematically. The optimal ceramic sample from the nanopowder calcined at 1050°C shows uniform and dense microstructure with the in‐line transmittance of 81.5% at 1100 nm. The results of the thermal measurements, that is, thermal conductivity and specific heat, were related to the changes occurring in the microstructure of the ceramics studied. It was shown on this basis that appropriate control of the technological process of sintering ceramics makes it possible to obtain laser ceramics with very good thermal properties as well as maintaining their high optical quality. Concerning the laser performance, the highest‐optical quality 5at.% Yb:Lu2O3 sample was pumped in quasi‐continuous wave conditions measuring a maximum output power of 2.59 W with a corresponding slope efficiency of 32.4%. [ABSTRACT FROM AUTHOR]

Under certain approximations, the Clapeyron equation can be integrated to yield a simple exponential relation giving the saturation vapor pressure over a condensed phase as a function of temperature. The derivation usually assumes that the vapor behaves as an ideal gas with constant specific heat, and that the fluid also has constant specific heat. In addition, the specific fluid volume is neglected in comparison with the specific vapor volume. In this case, the Clapeyron equation is separable and readily integrable in closed form. It is shown here that this latter assumption is not required. A simple closed‐form relation between saturation vapor pressure and temperature is derived which includes the condensed phase‐specific volume. Two examples of the use of this result are presented. [ABSTRACT FROM AUTHOR]

Aluminum alloy 5083 has low density, mechanical properties, high corrosion resistance, and high welding capability. Due to high thermal conductivity, specific heat, and latent heat, as well as the relatively high coefficient of thermal expansion of aluminum, achieving a connection with good mechanical properties is always very important. This study aimed to investigate nanoparticles' surprising and unexpected effects in forming various microstructures, which directly improve the mechanical properties of the welding process as a new and surprising idea. The effects of siliconized Zn-graphene oxide complex nanoparticles on weld geometry, mechanical properties, and microstructure of AA5083 were investigated. The gas metal arc welding process welded the samples, and different amounts of nanoparticles were investigated. The results reveal that utilizing nanoparticles can be affected by the weld geometry and the properties of weld metal. 0.25 g of nanoparticles had low face reinforcement, and the bead width and penetration depth dramatically increased. The presence of nanoparticles inside the molten zone and its effect on grain size improved mechanical properties, according to the Hall–Petch relationship. The ultimate tensile strength and yield strength of the S0.25 sample increased by 58.24 and 28.28%, respectively, compared to the welded sample without the presence of nanoparticles. Also, the ductility of this sample during the failure test showed that elongation increased by 36.75%. [ABSTRACT FROM AUTHOR]

High‐strength structural steels are beneficial in terms of the sustainability of constructions due to the possible reduction of weight and overall material needs. Nevertheless, high‐strength steels have a smaller processing parameter range in regarding the specific heat input and resulting cooling rate. Especially the cooling time t8/5 characterizing the time span to cool down from 800 to 500 °C is an important indicator. Single layer butt‐welded gas metal arc welding (GMAW) connections of 3 mm plates between normal strength (S355J2+N, S460MC) and high‐strength steels (S700MC) as well as matched connections (S460MC, S700MC) are carried out. Hereby, the influence of the energy input, melting rate, joint preparation, filler metal (matching and undermatching) and backing methods are observed. Spatially resolved IR‐thermal observation shows variations within the welds of up to 50 % in the cooling time t8/5 depending on those parameters. These fluctuations lead to significant changes of the microstructure within the melting and heat‐affected zone. UCI hardness mappings show the softening and microstructural change within these zones. Those soft zones can be the region of failure for butt welded connections as shown by transverse tensile tests with spatially resolved optical strain measurements. The results obtained can be used to define more precise welding procedures of these types of connections and also are used to develop design rules for mixed connections made of normal strength and high‐strength steel. [ABSTRACT FROM AUTHOR]

Limits of thermal tolerance in animal life is dependent on energy supply. Accordingly, the lowered ATP production capacity in ectotherms at high temperatures, which arises from a mismatch between oxygen supply and demand and the consequent switch from aerobic to anaerobic metabolism, affects the thermal resistance of these animals. The anaerobic ATP production capacity depends on the functional properties of the enzymes that reduce pyruvate. Thus, the present study focused on the role of the lactate dehydrogenase (LDH) of two daphnid species for anaerobic energy production at warm temperatures and the implications for their specific heat tolerances. Daphnia magna showed a higher thermal limit (indicated by immobilization time at 37°C) than Daphnia pulex, and in both species, this limit increased with rising acclimation temperature. In contrast to D. pulex, D. magna accumulated significant amounts of lactate at higher ambient temperatures. The intensity of anaerobic metabolism was also affected by acclimation temperature. Studying the functional enzyme properties revealed altered maximal reaction rates and substrate inhibitions of the LDH suites of the two daphnid species. D. magna LDH showed a significantly lower substrate inhibition than D. pulex LDH. The LDH isoform composition and the temperature‐induced changes differed between both species. The detected qualitative modulations of the LDH suites may have resulted from differential isoform expression and different maturation processes. The species‐specific LDH characteristics imply a higher anaerobic energy production at warm temperatures in D. magna, which likely contributes to the higher heat tolerance of this species. Research highlights: Heat tolerance in Daphnia is related tolactate production.Acclimation temperature affects LDH.LDH substrate inhibition prevents high lactate formation.Anaerobic LDH capacity is higher in Daphniamagna than in Daphniapulex.Differentia lLDH isoform expression adds to heat tolerance. [ABSTRACT FROM AUTHOR]

The heating stage in thermoforming of amorphous and semi‐crystalline polymers was analyzed for constant heat flux conditions using an energy balance model; candidate polymers were high impact polystyrene and isotactic polypropylene. Using an analytical solution, temperature differences as large as 100°C were predicted to arise between the surface and the interior of the sheet being thermoformed for conditions chosen in this work, and these can limit the heat flux being used. A Matlab program was used to compute temperature and crystallinity profiles for crystal melting. Melting took almost as much time as required to heat the surface of the film to the crystal melting point. High thermal conductivity additives, such as calcium carbonate and graphene, can provide temperature uniformity, and the additive uniformity can be verified using thermogravimetric analysis. The ability of these additives to provide temperature uniformity and to reduce energy consumption and heating time is determined in a quantitative manner. Both additives improve heat transfer, and, at the same added volume fraction, graphene is more effective. However, calcium carbonate has a lower cost. The role of density, specific heat, thermal conductivity, and amount of the polymers and additives in influencing temperature and crystallinity profiles was explored, and methods of carrying out thermoforming in an energy efficient manner are proposed. [ABSTRACT FROM AUTHOR]

Phosphate tungsten and molybenum bronzes represent an outstanding class of materials displaying textbook examples of charge‐density‐wave (CDW) physics among other fundamental properties. Here we report on the existence of a novel structural branch with the general formula [Ba(PO4)2][WmO3m−3] (m=3, 4 and 5) denominated ′layered monophosphate tungsten bronzes′ (L‐MPTB). It results from thick [Ba(PO4)2]4− spacer layers disrupting the cationic metal‐oxide 2D units and enforcing an overall trigonal structure. Their symmetries are preserved down to 1.8 K and the compounds show metallic behaviour with no clear anomaly as a function of temperature. However, their electronic structure displays the characteristic Fermi surface of previous bronzes derived from 5d W states with hidden nesting properties. By analogy with previous bronzes, such a Fermi surface should result into CDW order. Evidence of CDW order was only indirectly observed in the low‐temperature specific heat, giving an exotic context at the crossover between stable 2D metals and CDW order. [ABSTRACT FROM AUTHOR]