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The rising temperature due to a self-heating or thermal environment not only degrades the subthreshold performance but also intensifies thermal stress, posing a severe challenge to device performance and reliability design. The thermal stress effects on the ON-state performance of the p-type fin field-effect transistor were previously studied. However, as far as we know, how thermal stress affects its subthreshold conduction remains unclear, which is studied in this manuscript. The impact of thermal stress due to the self-heating of adjacent devices on subthreshold conduction is investigated by solving the quantum transport, thermal conduction, and force balance equations for ballistic transport and dissipative transport with phonon scattering. Then, the thermal stress effects at different ambient temperatures are further discussed and analyzed. The simulation results show that the OFF-state leakage current can be reduced by thermal stress, even up to 9.28% for the (110)/[001] device operating at an ambient temperature of 550 K, and its reduction is the comprehensive result of the thermal stress effects on the band structure, potential profile, carrier distribution, and source-to-drain tunneling. In addition, the thermal stress has no significant effects on subthreshold swing although it can change the magnitude of the subthreshold current. Moreover, the effect of thermal stress on subthreshold conduction is highly dependent on the thermal environment of the device and the crystal orientation of the channel semiconductor material. [ABSTRACT FROM AUTHOR]

A new diamond anvil cell experimental approach has been implemented at the European x-ray Free Electron Laser, combining pulsed laser heating with MHz x-ray diffraction. Here, we use this setup to determine liquidus temperatures under extreme conditions, based on the determination of time-resolved crystallization. The focus is on a Fe-Si-O ternary system, relevant for planetary cores. This time-resolved diagnostic is complemented by a finite-element model, reproducing temporal temperature profiles measured experimentally using streaked optical pyrometry. This model calculates the temperature and strain fields by including (i) pressure and temperature dependencies of material properties, and (ii) the heat-induced thermal stress, including feedback effect on material parameter variations. Making our model more realistic, these improvements are critical as they give 7000 K temperature differences compared to previous models. Laser intensities are determined by seeking minimal deviation between measured and modeled temperatures. Combining models and streak optical pyrometry data extends temperature determination below detection limit. The presented approach can be used to infer the liquidus temperature by the appearance of SiO 2 diffraction spots. In addition, temperatures obtained by the model agree with crystallization temperatures reported for Fe–Si alloys. Our model reproduces the planetary relevant experimental conditions, providing temperature, pressure, and volume conditions. Those predictions are then used to determine liquidus temperatures at experimental timescales where chemical migration is limited. This synergy of novel time-resolved experiments and finite-element modeling pushes further the interpretation capabilities in diamond anvil cell experiments. [ABSTRACT FROM AUTHOR]

Although previous research on climate change in the Arabian Peninsula (AP) has studied changes in individual meteorological variables, an analysis of changes in the overall weather conditions based on multiple meteorological variables is limited. Based on an air mass‐based classification system, this research explored the local climate (1979–2023) of daily surface weather conditions (i.e., air masses) and associated changes over the Peninsula. For this purpose, the gridded weather typing classification (GWTC‐2), an approach to classify multivariate surface weather situations relative to the average local climate, was utilized as it demonstrated outstanding performance in capturing daily weather characteristics in the Peninsula. Cold air mass (C), days with low temperature and near average humidity, was the most common cool weather type, with notable occurrences from Nov to Feb. Warm air mass (W), hot days with near average humidity, was the most common warm weather condition and maintained a marked presence throughout the year, with notable occurrences in summer. Coastal regions showed higher presences of humid warm (HW) and humid (H) days, whereas the central parts demonstrated higher occurrences of air masses of below‐average humidity (dry [D], dry cold [DC], and dry warm [DW]). Much of the Peninsula showed high intra‐annual variability in cool, warm, humid, and dry air masses. Findings from trend analysis reinforce findings from previous studies related to ongoing warming over the Peninsula, as cool weather types (DC, C, and HC) are becoming less frequent, while warm weather types (W, DW, and HW) are becoming more frequent. This analysis further detected decreases in the average weather conditions along with reduced duration of C‐type and increases in the length of warm weather types, further aggravating thermal stress across the AP. [ABSTRACT FROM AUTHOR]

Basal and prismatic slips induced by thermoelastic stresses during the growth of 4H-SiC are investigated by using the finite element method (FEM) and considering factors such as the crystal diameter, temperature, and off-axis angle. It is found that with the increase of the crystal diameter from 6 to 8 inches, the prismatic slip more likely occurs, leading to a higher density of basal plane dislocations (BPDs). However, the basal slip hardly changes. The temperature difference, rather than the growth temperature, is the primary factor contributing to the increase in the slip stresses. The stresses of the basal slip are significantly affected by a small off-axis angle, whereas those of the prismatic slip are not unaffected until the off-axis angle reaches 30 degrees. The mechanism for the decrease of the density of BPDs along the growth direction in an 8 inch 4H-SiC crystal is elucidated. We verify that the prismatic slip in an 8 inch 4H-SiC crystal contributes more to the BPD formation than the basal slip. [ABSTRACT FROM AUTHOR]

Spinel saggar was prepared using Magnesium Aluminum spinel (MgAl 2 O 4), KF and TiO 2 as primary raw materials. The saggar's toughness was enhanced through in-situ generation of potassium titanate whisker (PTW). The impact of sintering temperature on the saggar's phase composition, whisker growth and physical properties was investigated. The findings indicated that the spinel saggar exhibited high densities and robust mechanical strength following heat treatment at 800 °C for 3 h, with an apparent porosity of 27.9 %. The cold modulus of rupture (CMOR) and cold crushing strength (CCS) were measured at 5.58 MPa and 21.05 MPa, respectively. The saggar retained rate 75.6 % of their strength after three thermal cycles at 800 °C for 20 min followed by air cooling. Corrosion analysis identified LiAlO 2 as the primary corrosion product of the spinel saggar. PTW facilitated particle bonding, enhancing the strength and toughness of the spinel saggar. This promoted the dispersion and absorption of thermal stresses during cyclic corrosion to prevent further damage. In contrast, for cordierite-mullite saggar corrosion products included LiAlO 2 , eucryptite(β-LiAlSiO 4) and Li 4 SiO 4. The disparate thermal expansion among these phases resulted in the formation of through cracks, exacerbating saggar corrosion damage. The spinel saggar demonstrated superior performance during the cyclic corrosion process. [ABSTRACT FROM AUTHOR]

When electrophoretic deposition (EPD) is employed for fabricating alumina (Al 2 O 3)-based hydrogen barrier coatings, it becomes customary to enhance the adhesion strength by subjecting the deposited coating to high-temperature annealing. In this study, a functionally-graded Al 2 O 3 /ZrO 2 coating was designed by using the thermal stress module of Ansys software. The influence of different gradient composition distribution indices, number of layers, and layer thickness on the distribution of thermal stress was systematically investigated by simulation. Based on simulation results, the gradient parameters of the functionally-graded coating were determined as follows: a transition layer with three layers, each with a thickness of 0.13 mm; the first layer consisted of Al 2 O 3 to ZrO 2 ratio of 1:3, the second layer with a ratio of 1:1, and the third layer with a ratio of 3:1. Subsequently, the process parameters for EPD of Al 2 O 3 coating were optimized via experimental exploration. Under conditions of deposition time of 120 s, deposition voltage of 60 V, Al 2 O 3 concentration of 8 g L−1 in the electrophoretic solution, and magnesium chloride hexahydrate concentration of 0.6 g L−1, the as-fabricated Al 2 O 3 coating exhibited optimal hydrogen barrier performance. Finally, different proportions of ZrO 2 were sequentially incorporated into the prepared Al 2 O 3 coating to form functionally-graded materials (FGM). Thermal cycling experiments showed that the Al 2 O 3 coating with added ZrO 2 exhibited better stability at high temperatures. Regarding hydrogen barrier performance, the functionally-graded coating outperformed the non-functionally-graded coating. [ABSTRACT FROM AUTHOR]

As the most prospective media material for porous media burners, silicon carbide reticulated porous ceramic (SiC RPC) is required to possess a high porosity to fulfill efficient combustion, as well as exceptional thermal shock resistance to withstand the thermal stress generated during the start-up and shutdown processes. To achieve the strengthening and toughening of highly porous SiC RPC, three-layered struts were constructed, and in-situ whiskers were formed in SiC RPC through vacuum infiltration and sintering under a nitrogen atmosphere in this work. The results indicated that the three-layered struts were formed after the preform was conducted with vacuum infiltration, encompassing a mullite coating, a silicon carbide layer and a mullite inner layer. When Si powder and flake graphite were incorporated into the SiC slurry, numerous SiC whiskers were formed in situ within the SiC skeleton. The formation of SiC whiskers was attributed to the enhancement of SiC RPC, resulting in an increase in CCS from 0.22 MPa to 0.55 MPa. Additionally, the residual strength retention rate after water quenching at 1100 °C was elevated from 41.6 % to 70.2 %. Moreover, the SiC RPC containing SiC whiskers exhibited an impressively high porosity of 83 %, leading to a surface temperature of 688 °C and a heating efficiency of 16.4 °C/min during the combustion process. [ABSTRACT FROM AUTHOR]

Ceramic matrix composites (CMCs) have been widely used in aerospace thermal-structures due to their excellent high-temperature performance. It is essential to understand the damage evolution of CMCs. However, in previous research work, the effect of thermal stress induced damage during CMCs fabrication on tensile response was often ignored. A damage evolution model that considers axial and radial thermal stresses to predict tensile response of unidirectional ceramic matrix composites was proposed in this study. The average relative errors between the current prediction and experimental data in the literature were calculated as 1.64 % and 1.91 %, validating this approach. Meantime, the damage evolution laws of interface debonding and the critical stress of matrix cracking in the Budiansky–Hutchinson–Evans (BHE) model were corrected to satisfy the discontinuous interfacial shear stress. According to the experimental data, the current model predicted critical stresses of matrix cracking better than the BHE model, with error rate reductions of 6.52 % and 15.38 %. [ABSTRACT FROM AUTHOR]

In recent years, thermal barrier coatings (TBCs) have been extensively employed to safeguard turbine engine blades against high temperatures and harsh operating conditions. Mullite whiskers are frequently utilized to improve the mechanical properties of ceramic matrix composites because of their exceptional characteristics. This study investigates thermal stress in coating systems by analyzing the impact of varying content, aspect ratio, and deflection angle of mullite whiskers using finite element simulations under static conditions. Results demonstrated that incorporating mullite whiskers can mitigate the sudden stress variation between the ceramic coating and the substrate. The addition of mullite whiskers reduced the maximum stress value in the coating system, thereby enhancing its thermal stability and service life. The arrangement of mullite whiskers was controlled during the preparation procedure to ensure their proper orientation. The coating system exhibited higher mechanical properties at a certain position. This study provided a theoretical basis for the design of mullite whisker–reinforced TBCs. [ABSTRACT FROM AUTHOR]

Oil–pressboard insulation in converter transformer is subjected to the combined effects of AC and DC electric fields, high temperature, and mechanical vibration in actual operation, with a serious impact on its deterioration. In this study, comparative tests are performed of coupled electrical–thermal–mechanical aging, and several characteristic parameters that characterize the degree of aging of oil–pressboard are measured. Relationships between aging parameters are established, with the degree of polymerization (DP) of the pressboard being adopted as the criterion to characterize the degree of aging. Scanning electron microscopy and X-ray diffraction are used to investigate the surface morphology and crystal structure of the pressboard at different aging stages. Then, the influences of temperature, electric field and mechanical field on the cracking mechanism of the oil–pressboard insulation in terms of the aging characteristic parameters and the changes in cellulose crystallinity were analyzed. It is finally found that thermal stress is the most important factor involved in insulation pressboard cracking. The addition of electric and mechanical fields will reduce the crystallite size of the cellulose pressboard material, increase the acid value and furfural content of the oil, and increase the rate of decrease in the degree of polymerization of the pressboard. All of which accelerate the aging of the oil–pressboard insulation. [ABSTRACT FROM AUTHOR]

ABSTRACT Direct pulse‐width modulated (PWM) AC–AC converters are rapidly advancing, primarily because of their single‐stage power conversion and reduced footprint, achieved by eliminating the intermediate DC‐link capacitor. Z‐source AC–AC converters (ZSACs) especially have gained attention for their wide voltage range and reduced harmonic currents in applications where only voltage regulation is desired. Meanwhile, voltage regulation in PWM AC–AC converters necessitates effective closed‐loop control methods. Delta‐sigma modulation (DSM) has emerged as a promising technique, outperforming traditional methods. Nevertheless, the conventional DSM technique employs a fixed hysteresis band, resulting in the converter operating at a variable switching frequency. The variable switching frequency increases the switching losses, which puts more thermal stress on the switches. This paper introduces a CSF‐based DSM method for ZSACs that makes use of an adaptive hysteresis band. A four‐step commutation technique is utilized to prevent voltage and current spikes across the bidirectional switches, eliminating the need for snubber circuits. The proposed approach is validated through comprehensive simulation studies and experimental results on a modified quasi‐ZSAC topology using a 200‐W laboratory prototype, demonstrating significant improvements in source and load current total harmonic distortion (THD), dynamic response, and overall system performance while maintaining constant switching frequency. [ABSTRACT FROM AUTHOR]

This work addresses the challenges in brazing thermohydraulic sealings involving dissimilar materials, specifically 316Ti stainless steel and alumina, which have significantly different coefficients of thermal expansion (CTEs) and elastic constants. Traditional brazing methods require complex interlayers or extensive metallization steps, leading to issues such as dimensional changes, braze voids, and inadequate corrosion resistance due to prolonged high‐temperature exposure. A novel laser‐based brazing technique utilizing a diode laser is introduced to create high‐quality, localized joints while preserving the integrity of the parent materials. The study systematically optimizes laser process parameters using finite‐element modeling and the Taguchi method to achieve the desired bead geometry and thermal stress distribution with minimal heat input. Comparative analysis between laser active brazing (LAB) and conventional furnace brazing was conducted through metallography, shear testing, and autoclave testing. Results indicate that LAB parameters significantly affect bead thickness and shear strength, with laser‐brazed joints demonstrating superior quality and stability post‐autoclave testing compared with furnace‐brazed joints. The thermodynamic and kinetic aspects of the brazing process were also analyzed. In conclusion, the LAB method for brazing 316Ti to alumina proves to be a successful and efficient alternative, with joint properties meeting or exceeding those of traditional furnace brazing. [ABSTRACT FROM AUTHOR]

Porosity is a critical microstructural factor in ceramic materials, influencing their mechanical and thermal properties. However, the detailed mechanisms through which porosity, grain size, and grain boundary fracture energy affect the thermal shock resistance of porous ceramics are still not fully understood. This study introduces a dual‐scale model that integrates these microstructural parameters to predict fracture toughness and thermal shock resistance. Using the single‐edge V‐notch fracture toughness testing principle, we calculate the thermal stress intensity factor and establish its relationship with temperature differentials. The critical temperature differential, which marks the onset of thermal shock damage, is determined when the thermal stress intensity factor reaches the fracture toughness threshold. The model reveals a significant interplay between porosity, grain size, and grain boundary fracture energy, with fine‐grained ceramics (grain size < 10 µm) showing a sharp decrease in fracture toughness as porosity increases, while coarser‐grained ceramics are less affected by porosity. These findings provide a deeper understanding of the microstructural optimization needed to enhance the thermal shock resistance of high‐performance porous ceramics. [ABSTRACT FROM AUTHOR]

Organic–inorganic metal halide perovskite solar cells (PSCs) have attracted extensive attention from the photovoltaic (PV) community due to their fast-growing power conversion efficiency from 3.8% to 26.7% in only 15 years. However, these organic–inorganic hybrid PSCs suffer from inferior long-term operational stability under thermal and light stress, due to the fragile hydrogen bonds between organic cations and inorganic slabs. This motivates the exploration of more robust all-inorganic alternatives against external stimuli, by substituting inorganic cesium (Cs) cations for volatile organic cations. Despite reinforced ionic interaction between Cs cations and metal halide frameworks, these Cs-based all-inorganic perovskites tend to undergo spontaneous phase transition from photoactive black phases to non-perovskite yellow phases at room temperature, significantly deteriorating their optoelectronic performance. Thus, tremendous efforts have been made to stabilize the black phase of CsPbI3, while the phase instability issue of the tin-based analogue of CsSnI3 has not been resolved yet. This highlight article summarizes the empirical advances in stabilizing the metastable phases of CsPbI3, aiming to provide useful guidelines to accelerate the development of phase-stable CsSnI3 for durable lead-free PV applications. Finally, the remaining challenges and future research opportunities are outlined, providing a road map to realize efficient and durable all-inorganic perovskite solar cells towards practical applications. [ABSTRACT FROM AUTHOR]

With the development of the electronic packaging industry, there is an increased demand for enhanced strength in DBA substrates. Ultrasonic soldering technology allows low-temperature joining of ceramic-metal materials under ambient air conditions. In this paper, we successfully achieved the joining between AlN ceramics and 2024Al using Sn9Zn solder and ultrasonic soldering technique, while also analyzing the joining mechanism through Comsol software simulations. It was observed that under the appropriate ultrasonic amplitude and frequency, the Sn9Zn solder exhibited complete wetting with both base materials, resulting in reliable joints. Building upon this finding, the conventional Sn9Zn solder was further optimized by adding Sb element. The addition of Sb element led to the formation of Zn 4 Sb 3 phase and β-Sn(Sb) phase with Sb acting as solute. Among them, the generation of β-Sn(Sb) solid solution phase effectively improved the joint strength. The maximum joint strength was achieved at an average value of 75.066 MPa when the Sb content reached 1 wt. %. At this point, the failure occurred within the AlN ceramic base material. [ABSTRACT FROM AUTHOR]

A self-built automatic platform was built to evaluate the thermal shock performances of Cansas-III SiC fibers at 1200 °C in air up to 500 cycles, the corresponding oxidation and damage mechanisms were then revealed. The results showed that oxide scale was formed during thermal shock with a thickness of about 1 μm, the core was not oxidized via its protection. The fiber roughness increased before 100 cycles due to the decomposition of the amorphous SiC x O y phase, and then decreased as the formation of oxide scale. Within Cansas-III SiC fibers, structural defects of free carbon increased as the increasing I D /I G values, in addition, the TO peak shifted to the left, which both demonstrated that the relative movements occurred among SiC grains and residual stresses were then emerged. To clarify the axis and radial cracking of the oxide scale, a modified formulation considering nonzero shear strain components was then proposed to calculate the related residual stresses. The peeling and cracking of the oxide scale was ascribed to the residual stresses of GPa level among SiC grains and the thermal expansion mismatch between the oxide scale and the core. [ABSTRACT FROM AUTHOR]

This paper presents the results of a study of layer gradient thermal protection coatings based on NiCrAlY and YSZ obtained by detonation spraying. Modern gas turbines and high-temperature units operate under extreme temperatures and aggressive environments, which requires effective protection of components from wear, corrosion, and thermal shocks. In this study, the use of layer gradient coatings consisting of alternating layers of NiCrAlY and YSZ was investigated with the aim of solving the problem of thermal stress accumulation due to a smooth change in the composition of the layers. Microstructural and phase analysis showed that alternating layers of NiCrAlY and YSZ formed a dense layer gradient structure with clear interphase boundaries and low porosity. Detonation spraying led to a complete transformation of the monoclinic ZrO2 phase into a tetragonal one, which significantly increased the mechanical strength of the coating and its resistance to thermal shocks. Sample 1D1 demonstrated excellent tribological and corrosion properties in a 3.5% NaCl solution, which can be explained by its higher density and reduced number of pores. Mechanical tests revealed stable values of hardness and wear resistance of the coating, especially for the 1D1 coating. Studies have shown that coatings are resistant to thermal shocks, but thicker layers show a tendency to peel off after thermal cycling. The obtained results indicate high prospects for the use of layer gradient coatings based on NiCrAlY and YSZ for the protection of gas turbine components and other high-temperature installations operating under extreme loads and aggressive environments. [ABSTRACT FROM AUTHOR]

A novel TiB2-CeO2-modified (Nb,Mo,Cr,W)Si2 coating was prepared on a Nb-5W-2Mo-1Zr alloy substrate using two-step slurry sintering and halide-activated pack cementation to address the limitations of a single NbSi2 coating in meeting the service requirements of niobium alloys at elevated temperatures. At 1700 °C, the static oxidation life of the coating exceeded 20 h, thus indicating excellent high-temperature oxidation resistance. This was due to the formation of a TiO2-SiO2-Cr2O3 composite oxide film on the coating surface, which, due to low oxygen permeability, effectively prevented the inward infiltration of oxygen. Additionally, the dense structure of the composite coating further enhanced this protective effect. The composite coating was able to withstand over 1600 thermal shock cycles from room temperature to 1700 °C, and its excellent thermal shock performance could be attributed to the formation of MoSi2, CrSi2, and WSi2 from elements such as Mo, Cr, and W, which were added during modification. In addition to adjusting the difference in thermal expansion coefficients between the layers of composite coatings to reduce the thermal stress generated by thermal shock cycles, the formation of silicide compounds also improved the overall fracture toughness of the coating and thereby improved its thermal shock resistance. [ABSTRACT FROM AUTHOR]

Directed energy deposition with laser beam (DED-LB) components experience significant residual stress due to rapid heating and cooling cycles. Excessive residual tensile stress can lead to cracking in the deposited sample, resulting in service failure. This study utilized digital image correlation (DIC) and thermal imaging to observe the in situ temporal evolution of strain and temperature gradients across all layers of a deposited 316 L stainless steel thin wall during DED-LB. Both continuous-wave (CW) and pulsed-wave (PW) laser modes were employed. Additionally, the characteristics of thermal cracks and geometric dislocation density were examined. The results reveal that PW mode generates a lower temperature gradient, which in turn reduces thermal strain. In CW mode, the temperature–stress relationship curve of the additive manufacturing sample enters the "brittleness temperature zone", leading to the formation of numerous hot cracks. In contrast, PW mode samples are almost free of cracks, as the metal avoids crack-sensitive regions during solidification, thereby minimizing hot crack formation. Overall, these factors collectively contribute to reduced residual stress and improved mechanical properties through the adjustment of pulsed-wave laser deposition. [ABSTRACT FROM AUTHOR]

This paper examines the safety of aero-engine pipelines under different heating conditions. Based on the fire test standard documents, a model of an aero-engine oil pipe was constructed, and its safety under heating conditions that meet the standard was analyzed using fluid–solid thermal coupling. The pipe material was stainless steel 1Cr18Ni9Ti, and the oil inside the pipeline was China RP-3 kerosene. To simulate the different working conditions or pump failure scenarios, various kerosene inlet flow rates were used for the calculations. The results indicate that the pipe wall exhibits an uneven temperature distribution under standard heating conditions. As the kerosene flow rate decreases, the pipe wall temperature rises, and heat transfer deterioration occurs. The increase in the pipe wall temperature reduces the material's strength, while the uneven temperature distribution generates thermal stress, further increasing the safety risk. When the kerosene flow rate is reduced to a certain level, the equivalent stress in the pipe wall exceeds the material's yield strength, leading to a high risk of rupture. [ABSTRACT FROM AUTHOR]

Deep infection is the second most common complication of arthroplasty following loosening of the implant. Antibiotic-loaded bone cements (ALBCs) and high concentrations of systemic broad-spectrum antibiotics are commonly used to prevent infections following injury and surgery. However, clinical data fails to show that ALBCs are effective against deep infection, and negative side effects can result following prolonged administration of antibiotics. Additionally, the rise of multidrug resistant (MDR) bacteria provides an urgent need for alternatives to broad-spectrum antibiotics. Phage therapy, or the use of bacteriophages (viruses that infect bacteria) to target pathogenic bacteria, might offer a safe alternative to combat MDR bacteria. Application of phage therapy in the setting of deep infections requires formulation strategies that would stabilize bacteriophage against chemical and thermal stress during bone-cement polymerization, that maintain bacteriophage activity for weeks or months at physiological temperatures, and that allow for sustained release of phage to combat slow-growing, persistent bacteria. Here, we demonstrate the formulation of three phages that target diverse bacterial pathogens, which includes spray-drying of the particles for enhanced thermal stability at 37 °C and above. Additionally, we use atomic layer deposition (ALD) to coat spray-dried powders with alumina to allow for delayed release of phage from the dry formulations, and potentially protect phage against chemical damage during bone cement polymerization. Together, these findings present a strategy to formulate phages that possess thermal stability and sustained release properties for use in deep infections. [ABSTRACT FROM AUTHOR]

Extreme heat events are becoming increasingly common, and the short‐term acclimation of photosynthesis will have a large impact on plant performance. Trees in lowland tropical forests, which are hypothesized to have limited abilities to tolerate rising temperatures, may need to rely on short‐term acclimation of their more plastic traits, like photosynthetic thermal tolerance, to persist in the face of increasingly variable climates.Here, we investigated seasonal acclimation of thermal tolerances in plant species of the moist Amazon. Specifically, we measured the photosynthetic thermal tolerances of six common woody Amazonian species at the beginning and at the end of the dry season to determine the species' abilities to acclimate to intra‐annual changes to climate. In addition, we used the natural thermal gradient present at our research site to test the acclimation of individual plants to maximum air temperatures not currently observed elsewhere in the moist lowland Amazon (up to ~43°C).Between seasons, there were significant overall increases in the thermal tolerances of three species (i.e. higher thermal tolerances in the hotter dry season), suggesting that leaf megathermy is prominent in these species. Also, three species acclimated their thermal tolerances to microsite‐level differences in seasonal temperature maxima, suggesting closer fidelity between leaf and air temperatures (i.e. limited homeothermy) for these species.Our results show that some woody species from the moist Amazon can acclimate their thermal tolerances over short time‐scales, although acclimation is likely insufficient to overcome thermal stress during extreme temperature events. Some species may therefore be more sensitive to heatwaves than others, which could impact survival and composition of tropical lowland forests into the future. Read the free Plain Language Summary for this article on the Journal blog. [ABSTRACT FROM AUTHOR]

Lithium-based battery systems (LBS) are used in various applications, from the smallest electronic devices to power generation plants. LBS energy storage technology, which can offer high power and high energy density simultaneously, can respond to continuous energy needs and meet sudden power demands. The lifetime of LBSs, which are seen as a high-cost storage technology, depends on many parameters such as usage habits, temperature and charge rate. Since LBSs store energy electrochemically, they are seriously affected by temperature. High-temperature environments increase the thermal stress exerted on LBS and cause its chemical structure to deteriorate much faster. In addition, the fast charging feature of LBSs, which is generally presented as an advantage, increases the internal temperature of the cell and negatively affects the battery life. The proposed energy management approach ensures that the ambient temperature affects the charging speed of the battery and that the charging speed is adaptively updated continuously. So, the two parameters that harm battery health absorb each other, and the battery has a longer life. A new differential approach has been created for the proposed energy management system. The total amount of energy that can be withdrawn from LBS is increased by 14.18% as compared to the LBS controlled with the standard energy management system using the genetic algorithm optimized parameters. Thus the LBS replacement period is extended, providing both cost benefits and environmentally friendly management by LBSs turning into chemical waste distinctly later. [ABSTRACT FROM AUTHOR]

The publication addresses the dynamic state challenges encountered during development of a dual active bridge (DAB) converter within DC microgrid systems. The conventional startup method is identified as instigating a cascade of unfavorable outcomes, encompassing elevated starting current, transformer current asymmetry, DC voltage distortions, EMI and heightened thermal stress on semiconductor components. Additionally, it necessitates precise calibration of magnetic components and diodes. A proposed remedy to these issues is introduced, involving a control method based on an additional phase shift to modulate the current of the primary H bridge. This novel control methodology is posited as a means to mitigate the aforementioned undesirable effects associated with traditional converter initiation techniques. The research also delves into considerations of a proper design procedure for the converter. Emphasis is placed on integrating the novel control methodology into the design framework in order to effectively address challenges arising during transient states. Validation of the proposed solution is substantiated through a series of laboratory tests, the results of which are comprehensively presented in the article. These tests affirm the efficiency of the system when incorporating the novel control methodology, thereby substantiating its practical utility in mitigating the issues identified during the initiation phase of the DAB converter in DC microgrid systems. [ABSTRACT FROM AUTHOR]

Different responses or tolerance to thermal stress between invasive and native species can affect the outcome of interactions between climate change and biological invasion. However, knowledge about the physiological mechanisms that modulate the interspecific differences in thermal tolerance is limited. The present study analyzes the metabolic responses to thermal stress by the globally invasive turtle, Trachemys scripta elegans, as compared with two co‐occurring native turtle species in China, Pelodiscus sinensis and Mauremys reevesii. Changes in metabolite contents and the expression or enzyme activities of genes involved in energy sensing, glucose metabolism, lipid metabolism, and tricarboxylic acid (TCA) cycle after exposure to gradient temperatures were assessed in turtle juveniles. Invasive and native turtles showed distinct metabolic responses to thermal stress. T. scripta elegans showed greater transcriptional regulation of energy sensors than the native turtles. Enhanced anaerobic metabolism was needed by all three species under extreme heat conditions, but phosphoenolpyruvate carboxykinase and lactate dehydrogenase in the invader showed stronger upregulation or stable responses than the native species, which showed inhibition by high temperatures. These contrasts were pronounced in the muscles of the three species. Regulation of lipid metabolism was observed in both T. scripta elegans and P. sinensis but not in M. reevesii under thermal stress. Thermal stress did not inhibit the TCA cycle in turtles. Different metabolic responses to thermal stress may contribute to interspecific differences in thermal tolerance. Overall, our study further suggested the potential role of physiological differences in mediating interactions between climate change and biological invasion. [ABSTRACT FROM AUTHOR]

ABSTRACT Aim Location Taxa Methods Results Main Conclusions Surveying the demography of populations near species range edges may indicate their vulnerability to range contractions or local extinction as the climate changes. In the rocky intertidal, not only are latitudinal ranges constricted by thermal stress, but tides also create zonation or a ‘vertical range’ driven by sharp environmental gradients. By investigating demographics along the latitudinal and vertical ranges simultaneously, we can investigate whether populations may be vulnerable to a changing climate.Rocky intertidal habitats along west coast of the United States.Ochre sea star Pisaster ochraceus, six‐armed sea star Leptasterias spp., emarginate whelks (Nucella ostrina and N. emarginata) and channeled whelk N. canaliculata.In 2018, we surveyed the demographics of the taxa above at 33 sites spanning > 11° latitude from central Oregon to southern California, near the southern range limits of each taxon. We counted and sized individuals from the high to low intertidal zone. To understand how environmental stress changed with latitude, we evaluated intertidal temperatures in situ, as well as tidal extremes, tidal amplitude and wave exposure using offshore buoys.For all taxa, population density, the relative proportion of smaller individuals (except for emarginate whelks) and the upper vertical limits on the shore declined from north to south as temperatures increased and high tide height, tidal amplitude and wave heights decreased. In addition, smaller individual Leptasterias spp. generally inhabited lower shore levels while smaller individual emarginate whelks inhabited higher shore levels coastwide. For N. canaliculata, smaller animals were higher on shore northward, but lower on shore southward.While this study is a snapshot in time and cannot assess impacts of climate change, our surveys suggest environmentally‐related demographic limitation toward southern range limits and demographically vulnerable southern populations. Therefore, a warming climate may cause local extinctions or range contractions near southern limits. [ABSTRACT FROM AUTHOR]

Exposure to heat stress can cause a significant increase in the death rate and disease susceptibility of poultry birds, ultimately impacting the profitability of the poultry industry. Despite being a more economical choice, Japanese quails (Coturnix japonica) are not immune to the harmful effects of heat stress. Quails may experience negative effects on their reproductive performance due to excessive reactive molecules caused by heat stress. However, they have developed various mechanisms to maintain their reproductive abilities in such conditions. The neuroendocrine system in birds plays a vital role in regulating their reproductive responses to thermal stress, and it is also connected to other environmental factors such as photoperiod that can impact their reproductive performance. Hormones are crucial in the complex interactions necessary for sexual maturation and reproductive responses to heat stress in Japanese quails living in stressful thermal conditions. [ABSTRACT FROM AUTHOR]

• A reverse phase high performance liquid chromatography (RP-HPLC) method was developed to detect tonabersat in lipid-based formulations. • The developed method is highly sensitive and selective for tonabersat. • Good resolution was observed between Tonabersat and its degradation products. • The method was validated as per ICH guidelines. • This is the first published stability-indicating HPLC method for detection of tonabersat. A stability-indicating reversed-phase high-performance liquid chromatography (RP-HPLC) method was developed to assay tonabersat and assess its stability in pharmaceutical formulations. Chromatographic separation was achieved using a Kinetex® C18 column (2.6 µm, 150 x 3 mm, 100 Å) at 50 °C, with a 20 µL injection volume. A linear gradient of acetonitrile in water (5 – 33.5 %) was applied for 1 min, followed by a gradual increase to 100 % over 26 min at a flow rate of 0.5 mL/min. Tonabersat and its degradation products were detected at 275 nm and 210 nm, respectively. The optimized method was used to evaluate the stability of tonabersat in lipid-based pharmaceutical formulations at 5 ± 3 °C, 25 ± 2°C/60 ± 5 % RH, and 40 ± 2 °C/75 ± 5 % RH over 3 months. The method was validated as per ICH guidelines and demonstrated linearity in the range of 5 – 200 µg/mL (R2 = 0.99994) with good accuracy (98.25 – 101.58 % recovery) and precision (% RSD < 2.5 %). The limits of detection and quantitation were 0.8 µg/mL and 5 µg/mL, respectively. Forced degradation studies showed significant degradation on exposure to alkaline (90.33 ± 0.80 %), acidic (70.60 ± 1.57 %), and oxidative stress (33.95 ± 0.69 %) at 70 °C, but no degradation was observed on exposure to thermal or photolytic stress. No chemical degradation was observed in either formulation on storage. Thus, the method was sensitive, specific, and suitable for stability testing of tonabersat in pharmaceutical formulations. [ABSTRACT FROM AUTHOR]

Purpose: To find the quasi-static thermoelastic stress and displacement, the proposed model looks at how the microstructures interact with each other and how the temperature changes inside a rod. It uses the fractional-order dual-phase-lag (FODPL) theory to derive analytical solutions for one-dimensional problems in nonsimple media within the MDD framework. The dimensionless equations are used to analyze a finite rod experiencing the heat sources continuously distributed over a finite portion of the rod which vary with time according to the ramp-type function with other sectional heat supplies kept at zero temperature. The study introduces a technique using integral transforms for exact solutions in the Laplace transform domain for different kernel functions. Design/methodology/approach: A novel mathematical model incorporating dual-phase-lags, two-temperatures and Riesz space-fractional operators via memory-dependent derivatives has been established to analyze the effects of thermal stress and displacement in a finite rod. The model takes into account the continuous distribution of heat sources over a finite portion of the rod and their time variation according to the ramp-type function. It incorporates the finite Riesz fractional derivative in two-temperature thermoelasticity with dual-phase-lags via memory effect, and its solution is obtained using Laplace transform with respect to time and sine-Fourier transform with respect to spatial coordinates defined over finite domains. Findings: In memory-dependent derivatives, thermal field variables are strongly influenced by the phase-lag heat flux and temperature gradient. The non-Fourier effects of memory-dependent derivatives substantially impact the distribution and history of the thermal field response, and energy dissipation may result in a reduction in temperature without heat transfer. The temperature, displacement and stress profile exhibit a reduced magnitude with the MDD effect compared to when the memory effect is absent (without MDD). To advance future research, a new categorization system for materials based on memory-dependent derivative parameters, in accordance with the principles of two-temperature thermoelasticity theory, must be constructed. Research limitations/implications: The one-dimensional assumption introduces limitations. For example, local heating of a one-dimensional plate will not extend radially, and heating one side will not heat the surrounding sides. Furthermore, while estimating heat transfer, object shape limits may apply. Originality/value: This paper aims to revise the classical Fourier law of heat conduction and develop analytical solutions for one-dimensional problems using fractional-order dual-phase-lag (FODPL) theory in nonsimple media in the context of MDD. [ABSTRACT FROM AUTHOR]

Aim: As global climate changes, there is a clear mismatch between the temporal and spatial characteristics of body temperature and environmental temperature, confounding the assessment of thermal stress for organisms in many ecological studies. Here, we hindcast the hourly body temperatures of intertidal molluscs to explore the differences between them and environmental temperatures (air and water temperatures) in multiple metrics of thermal stress. Location: Intertidal shores in East Asia (0°–45°N, 100°E–140°E). Time Period: 40 years, 1980 to 2019. Major Taxa Studied: Mollusca. Methods: We collected habitat zonation data and measured the morphological characteristics of 25 intertidal molluscs living in East Asia. For three different types of intertidal molluscs (i.e., bivalves, limpets and snails), we built corresponding heat budget models (HBMs) to hindcast the hourly body temperatures from 1980 to 2019. We analysed the thermal stress of intertidal species faced in three metrics, annual extreme high temperatures (T99), seasonal daily maximum temperatures (DMT) and heatwaves, and compared them with environmental temperatures. Results: We found that T99 of body temperatures and their interannual warming rates are significantly higher than those of environmental temperatures. Moreover, there were non‐negligible mismatches between the seasonal thermal pattern and heatwaves of body temperatures and environmental temperatures, suggesting that the deleterious impacts of global warming on intertidal species are underestimated and cannot be directly revealed by environmental temperatures. Main Conclusions: Thermal stress patterns of body temperature were significantly different from those of environmental temperature, and the thermal stress faced by intertidal species had been persistently underestimated. These results emphasise that body temperature should be used as the appropriate metric for evaluating and predicting the impacts of global warming and weather extremes in the intertidal biological system. [ABSTRACT FROM AUTHOR]

Heatwaves are becoming more common due to climate change. Species can respond to this thermal stress through rapid behavioural changes. For example, parental care can increase reproductive success by buffering against thermal stress, but the ability to provide parental care may also be influenced by prior exposure to high temperatures. However, the effects of heatwaves in parents' early development on parental care they provide in adulthood have not yet been tested. Here, we addressed this knowledge gap using the burying beetle Nicrophorus vespilloides , an ectotherm model system with facultative biparental care. We compared the parental behaviour, reproductive success and offspring fitness of parents that had been exposed to a heatwave (3 days at 25 °C) early in the pupae stage in their development and parents that had been reared at a constant temperature. Females from the heatwave treatment were more likely to provide care than those in the control treatment, with no difference in reproductive success or offspring fitness between thermal treatments. Our findings suggest that heatwaves during the pupae development stage can potentially have long-term impacts on the likelihood of providing parental care later in life. • Females experiencing heatwaves as pupae were more likely to provide parental care. • Direct but not indirect parental care was impacted by heatwaves. • There was no impact of heatwaves on reproductive success or offspring fitness. [ABSTRACT FROM AUTHOR]

Exposure to temperatures outside of a fish's optimal range results in suppression of the immune system, ultimately leaving aquaculture stocks susceptible to disease outbreaks. This effect is exacerbated in triploid fishes, which demonstrate greater susceptibility to stress than their diploid counterparts. This study investigates the impacts of acute heat stress on the abundance of immune transcripts and proteins in diploid and triploid Chinook salmon (Oncorhynchus tshawytscha), an important finfish crop. This study also demonstrates that acute heat stress induces significant increases in the abundance hsp70, hsp90 and il1b transcripts in the head kidneys, gills and heart ventricles of both diploid and triploid Chinook salmon. Widespread dysregulation of antigen‐presentation transcripts was also observed in fish of both ploidies. These results suggest that acute heat stress activates acute‐phase responses in Chinook salmon and dysregulates antigen presentation, potentially leaving fish more susceptible to infection. At the protein level, IL‐1β was differentially expressed in the head kidney and ventricles of diploid and triploid salmon following heat shock. Differential expression of two tapasin‐like proteins in diploid and triploid salmon subjected to heat shock was also observed. Altogether, these data indicate that diploid and triploid Chinook salmon respond differently to acute thermal stressors. [ABSTRACT FROM AUTHOR]

Air oxidation is the main cause of the excessive consumption of prebaked anodes, which not only wastes carbon resources but also increases carbon emissions. In this study, a quasi‐molten coating with self‐healing for prebaked anode by using the slurry method was proposed. This coating utilizes the viscous molten liquid phases to bond the carbon anode, absorbs thermal stress, insulates the carbon anode from the air, and provides self‐healing capabilities at elevated temperatures, while the solid phase provides toughening properties. A series of oxidation experiments have shown that the coating has superior oxidation resistance than coatings reported in the literature. [ABSTRACT FROM AUTHOR]

The thermal shock resistance of ceramics is a key factor for determining the durability of ceramic components under transient thermal conditions and is also one of the key factors for evaluating the stability of ceramics under extreme thermal conditions. After rapid heating or cooling, the surface and internal thermal stress mismatches of ceramics can cause severe thermal damage. Two main types of ceramic thermal shock exist: rapid cooling and rapid heating thermal shock. This article presents a broad understanding and insight into fundamental theory and experimental methods for ceramic thermal shock testing. The experimental equipment and procedures, test result evaluation, and material characterization of ceramic thermal shock are summarized. Moreover, outlooks and perspectives are discussed for testing and characterizing ceramic thermal shock resistance. This review will be helpful to researchers performing studies in the relevant fields of ceramics. [ABSTRACT FROM AUTHOR]

This retrospective study utilized a mixed-effects logistic model analysis to investigate variables associated with the probability of pregnancy loss (PL) between days 30 and 70 in a dataset comprising 9507 pregnancies from a single cattle herd over 10 years. The model incorporated fixed-effect variables including cow breed (Holstein, Crossbred, and Brown Swiss), parity (1st, 2nd, 3rd, and 4th or more), insemination seasons, insemination number (≤3 vs >3), estrus nature (spontaneous vs synchronized), postpartum problems, sire breed (Holstein, Fleckvieh, Brown Swiss, and Montbéliarde), zygote genotypic (pure vs crossbred), days in milk (DIM) at insemination, actual 305-day milk yield, and sire conception rate. Additionally, random effects included sire (n = 129), cow (n = 3463), and production years (n = 10). The results revealed that cows inseminated with Brown Swiss sires or sires with lower initial conception rates had higher PL rates. Biparous cows, cows with lower 305-day milk yield, cows inseminated later in DIM, cows receiving the 4th or subsequent insemination, and cows inseminated during winter or autumn had lower PL rates. The estrus type and zygote genotype did not significantly impact PL. The random effects of cow, sire, and production years were estimated at 0.230, 0.054, and 0.112, respectively. In conclusion, the study findings suggested that improving management practices for high-yielding cows, cows in early lactation stages, and cows exposed to thermal stress conditions, along with utilizing Brown Swiss cows and sires with high initial conception rates per insemination, could potentially decrease overall PL rates on the farm. Nonetheless, the results did not support the use of Crossbred cows, sires from different breeds, or specific sires to mitigate PL rates on the farm. • Individual sires in a cohort of 129 sires did not influence the pregnancy loss (PL). • Cows inseminated with sires that had higher day-30 conception exhibit lower PL. • Cows that had higher 305-day milk yield exhibit a higher possibility of PL. • Biparous cows and cows that had higher DIM at insemination exhibit lower PL. • Type of estrus and genotype of the zygote did not influence the PL. [ABSTRACT FROM AUTHOR]

Cracks induced by internal stresses compromise the structural integrity of ceramic laminates. Such stresses can be classified into thermal stress derived from thermal expansion mismatch and shrinkage stress derived from shrinkage mismatch. Analytical models have been proposed for the former, whereas only numerical predictions have been explored for the latter. In this study, an equation is constructed to predict the shrinkage stress by modifying an elastic solution proposed in previous studies. We fabricated laminates with three‐layer sandwiched structures using only alumina specimens with high and low densities to control the shrinkage and avoid thermal mismatch. Surface cracks were initiated when the shrinkage stress exceeded the flexural strength of the surface layer. Although the original strength of the surface layer was 308.8 MPa, the laminates' flexural strength was lower than that because of shrinkage constraint. Our results demonstrate that the shrinkage stress was successfully estimated analytically using a few material properties measured in an ordinary environment. This study will ensure the structural integrity of ceramic laminates in laminate designs. [ABSTRACT FROM AUTHOR]

Based on experimental data, this study presents a model of the dynamic growth of a thermally grown oxide (TGO) in thermal barrier coatings (TBCs) during thermal cycling. The model was solved using the finite element method. The thermal stress results of the model were compared with experimental results to verify the accuracy of the model. The stress analysis revealed that the combined effect of radial tensile stress and circumferential compressive stress can lead to the delamination of TBCs in a buckling form, which can induce the formation of cracks in TBCs along the axial direction. This observation was consistent with the conclusions drawn from the experimental results. Crack initiation and propagation result from the action of the maximum shear and radial stresses. In addition, the relationship between buckling failure and microscopic cracks was investigated. Thermal cycling induces radial and circumferential cracks, leading to buckling, delamination, and ultimate coating failure as the radial and circumferential cracks interact at the interface. [ABSTRACT FROM AUTHOR]

Double‐layer thermal barrier coatings are one of the development directions of thermal barrier coatings technology. LaYbZr2O7 (LYZO) has high toughness and low thermal conductivity, making it promising for use as a high‐temperature thermal barrier coating. However, its relatively poor mechanical properties, especially low fracture toughness, limit its further application. Therefore, we prepared a double‐layer coating of LYZO and Y2O3 partially stabilized ZrO2 (YSZ) using atmospheric plasma spraying, with the inner layer being YSZ and the outer layer being LYZO. The results showed that after spraying, LYZO was in the metastable fluorite phase, while YSZ was in the tetragonal phase. LYZO and YSZ had good chemical compatibility, and an interaction layer formed at the interface between them, with its thickness increasing with the sintering time. Eventually, after 100 h of heat treatment, the thickness reached 12 µm. The hardness of the LYZO/YSZ interface increased with the sintering time, reaching a maximum value after sintering at 1300°C for 10 h. When evaluating the interfacial bonding strength using indentation method, the length of cracks caused by indentation significantly decreased with the increase of sintering time. The increase in bonding strength can be attributed to the formation of a reaction layer and the reduction of thermal residual stresses. Raman spectroscopy was used to measure the thermal residual strain at the LYZO/YSZ interface. Unbalanced distribution of thermal residual stress and M phase was observed near the interface. As the sintering time increased, both thermal residual stress and M phase content decreased. In summary, the double‐layer thermal barrier coating of LYZO/YSZ has good potential for development. [ABSTRACT FROM AUTHOR]

• Reliability-based non-probabilistic multiscale topology optimization (NRBMTO) with stress constrained is proposed. • The p-norm function aggregates global unit stresses. • Mechanical and thermo-mechanical loads are considered as non-probabilistic uncertain parameters. • Ellipsoid modeling describes uncertainty in non-probabilistic random variables. • NRBMTO results in more security than the traditional deterministic multiscale topology optimization (DMTO) approach. A reliability-based non-probabilistic multiscale topology optimization (NRBMTO) method with stress constraints is proposed for thermo-mechanical continuous structures with uncontrollable stresses. The physical parameters, external loads and temperature values at the macro scale, are regarded as non-probabilistic uncertain parameters in the optimization of structural topologies with complex physical fields at multi-scale. The homogenization-based finite element method is employed to quantify thermo-mechanical structures with multi-scale uncertain parameters in the established multi-scale topology model. The ellipsoid model is applied to describe the uncertainty of non-probabilistic random variables, and the non-probabilistic reliability index is obtained by estimating the failure probability based on the first-order reliability method (FORM). The unit stresses are aggregated to the global maximum stresses with the normalized p-norm function, taking into account the mechanical and thermal stresses. The sensitivity information of the compliance and stress constraint to the macro- and micro-design variables and uncertain variables are derived simultaneously. The macro- and micro- design variables are solved by the method of moving asymptotes (MMA), respectively. Several numerical examples are given to verify the effectiveness and feasibility of the proposed NRBMTO method. The results demonstrate that the optimized structure based on the NRBMTO method provides better security with reliability index β =3 and minimum compliance (244.39) while stress is controlled below 235 MPa compared to the classical deterministic multiscale topology optimization (DMTO) method. [ABSTRACT FROM AUTHOR]

Metallic nanowires, particularly polyol-grown silver nanowires, exhibit a morphological instability at temperatures significantly lower than their bulk melting point. This instability is commonly named after Rayleigh's description of the morphological instability of liquid jets, even though it has been shown that its quantitative predictions are not consistent with experimental measurements. In 1996, McCallum et al. proposed a description of the phenomenon assuming a solid wire lying on a substrate. It is assumed that the latter description depicts more accurately the reality. Nanowires with varying diameters have been deposited on silicon wafers. Statistical analysis of their radius and the wavelength of their periodical instability have been performed. McCallum et al.'s model better aligns with experimental observations compared to Rayleigh's description. This validation provides a robust theoretical framework for enhancing the stability of nanowires, addressing a crucial aspect of their development. [ABSTRACT FROM AUTHOR]

The study proposes incorporating human bodily comfort performance through a simulation method to assess the impact of urban microclimate conditions in an urban campus area. A human comfort performance matrix is used based on PET value and gender's thermal stress conditions. The investigation serves as a way to evaluate open spaces' climatic performance quantitatively through energy simulation. The method shows a way to measure urban comfort regarding gender perspectives early in the urban decision-making process. The findings of this research have practical implications for urban decision-makers to use robust simulation tools to optimize open space configurations based on gender's thermal performances. [ABSTRACT FROM AUTHOR]

Enhancing the lifetime of perovskite solar cells (PSCs) is one of the essential challenges for their industrialization. Although the external encapsulation protects the perovskite device from the erosion of moisture and oxygen under various harsh conditions. However, the perovskite devices still undergo static and dynamic thermal stress during thermal and thermal cycling aging, respectively, resulting in irreversible damage to the morphology, component, and phase of stacked materials. Herein, the viscoelastic polymer polyvinyl butyral (PVB) material is designed onto the surface of perovskite films to form flexible interface encapsulation. After PVB interface encapsulation, the surface modulus of perovskite films decreases by nearly 50%, and the interface stress range under the dynamic temperature field (−40 to 85 °C) drops from −42.5 to 64.8 MPa to −14.8 to 5.0 MPa. Besides, PVB forms chemical interactions with FA+ cations and Pb2+, and the macroscopic residual stress is regulated and defects are reduced of the PVB encapsulated perovskite film. As a result, the optimized device's efficiency increases from 22.21% to 23.11%. Additionally, after 1500 h of thermal treatment (85 °C), 1000 h of damp heat test (85 °C & 85% RH), and 250 cycles of thermal cycling test (−40 to 85 °C), the devices maintain 92.6%, 85.8%, and 96.1% of their initial efficiencies, respectively. [ABSTRACT FROM AUTHOR]

The indoor environment in most of the tropical coastal regions is associated with the residents' health and well-being. However, limited studies reported on quantifying the interrelation between indoor environmental quality, thermal comfort and residents' health risks in such climatic regions. Here, we evaluate indoor thermal comfort in coastal eastern India that falls under the ' Tropical Savanna ' climatic region. The perception survey was conducted to collect primary data in summer, monsoon, post-monsoon and winter across the year and the perception of warmth appeared to have a similar trend to direct and rational human thermal indices derived from a composite body heat exchange. Results indicate that indoor thermal stress significantly differed (p <.05) between seasons and across study locations. The maximum summer and monsoon days lay in a warm to very hot zone. Additionally, most of the heat-related stress or disorders significantly differed (p <.01) amongst different age groups of people. Finally, a principal component analysis using the human thermal indices yielded three groups of heat-related symptoms (a) physical fatigue and responses, (b) neural stressors and (c) hyperhidrosis disorder. Overall, results suggested that physical fatigue and responses arose predominantly from climate-induced thermal stress. The study recommends an effective bioclimatic design strategy following human-environment friendliness that can improve indoor thermal comfort in coastal eastern India. [ABSTRACT FROM AUTHOR]

Up to now, the UK has avoided major marine heatwaves (MHWs) that cause severe damage to marine ecosystems and the blue economy. However, an unprecedented in its intensity, though short-lived, MHWoccurred in UK waters in June 2023. This event sounded an alarm bell, highlighting gaps in our understanding of MHW characteristics and their potential future impacts in the UK. Here, we use a combination of remote sensing data and model output to characterise MHWs and Marine Cold Spells (MCSs) around the UK and the wider North Atlantic, and to assess the potential for concurrent biogeochemical extreme events. Results indicate that across the wider North Atlantic, the UK is not a hot spot for MHWs or MCSs but, regionally, the southern North Sea experiences the most activity. This is also the location of extreme chlorophyll-a concentrations, here termed blue waves (low chlorophyll-a) and green waves (high chlorophyll-a). However, there is not a very pronounced relationship between temperature and chlorophyll-a extremes, which may be impacted by the exact location, drivers and season of occurrence. In contrast, the southern North Sea and English Channel may experience a MHW and low near-bottom oxygen compound events year-round, which, due to the combination of thermal stress and reduced oxygen availability, may negatively impact benthic marine ecosystems. While MHWs in UK waters do not appear to be as long-lasting or intense as other well-documented events around the world, they are projected to increase. Thus, the UK has a unique opportunity to learn from other nations and so develop robust and comprehensive policies to increase preparedness and response capability for future extreme events. [ABSTRACT FROM AUTHOR]

Temperature is a critical environmental factor influencing insect development, physiology, and distribution. Global warming is predicted to increase the frequency and severity of extreme heat events, influencing insects differently across life stages. This study investigates the effects of short- and long-term thermal stress on the tobacco cutworm, Spodoptera litura, a polyphagous pest damaging over 389 plant species. We exposed eggs, larvae, pupae, and adults to elevated temperatures of 42°C and 46°C for four hours and one hour, respectively, in single and repeated occasions for two, four, two and two days for egg, larva, pupa and adults, respectively. Our results demonstrate significant variation in biological and reproductive fitness parameters across treatments. Notably, thermal stress skewed the sex ratio towards females. We also observed impacts on offspring survival and potential negative carry-over effects. Overall, the effects of heat stress were dependent on temperature, exposure duration, and life stage, with adults exhibiting the highest tolerance. These findings suggest that S. litura possesses a degree of heat tolerance that may enable it to survive summer heat waves, but its offspring and other life stages could be more vulnerable under future climate scenarios. [ABSTRACT FROM AUTHOR]

The crystallization thermal stability plays an essential role in affecting thermal stress of glass-ceramic sealant for long-term planar-type solid oxide fuel cells (SOFC) to prevent fuel leakage during operation. Due to the lack of systematic research on regulating the stable performance of glass-based sealant with the working time at operation temperature, herein, the effect of MgO on crystallization kinetics, phase stability, and thermal and mechanical properties of MgO–BaO–CaO–Al 2 O 3 –B 2 O 3 –SiO 2 (MBCABS) glass-ceramic has been firstly analyzed at heat-treatment of 750 °C with working time of 1∼1000h in this work. Subsequently, the relationship evolution of crystallization thermal stability-coefficient of thermal expansion (CTE) match-thermal stress was established by Finite Element Method (FEM). The main reasons for the decrease of CTE of MBCABS glass-ceramics with low-content MgO are the precipitation of hexagonal BaAl 2 Si 2 O 8 phase and the transformation of hexagonal BaAl 2 Si 2 O 8 to low-CTE monoclinic BaAl 2 Si 2 O 8 phase, bring about that the Von Mises thermal stress of sealant itself and interface having tripled at 1000h (more than 200 MPa) according to FEM simulation results. The thermal stable and high-CTE BaMgSiO 4 , Ba 8 Mg 16 Si 16 O 56 , and BaCa 2 Mg(SiO 4) 2 phases crystallized in MBCABS glass-ceramics with high-content MgO, therefore the maximum stress at all time parameters was below 100 MPa for 1∼1000h. This study was useful for identifying the optimal phase option and CTE matching of glass-based sealant for efficient and stable long-term operation of solid oxide fuel cells. [ABSTRACT FROM AUTHOR]

Mechanical behavior of B 4 C - HfB 2 particulate ceramic composite doped with CrB + Cr 3 B 4 chromium boride compounds were studied by nanoindentation. Hardness, Young's modulus, and indentation stress - indentation strain behavior of B 4 C and HfB 2 phases was computed. It was found that hardness and Young's modulus of B 4 C matrix phase in B 4 C - HfB 2 doped with Cr - B was increased as compared to those hardness and Young's modulus of pure B 4 C. It was also found that indentation stress was relieved by "pop-in" events in some of the B 4 C grains, however, the "pop-in" discontinuous events were always observed upon indentation of HfB 2 grains, that lead to a decrease in hardness of HfB 2 from 40 to 50 GPa before "pop-ins" to 28–32 GPa after "pop-ins". The obtained results can be further used in calculations of thermal residual stresses in B 4 C and HfB 2 phases of B 4 C - HfB 2 particulate ceramic composite. [ABSTRACT FROM AUTHOR]

In this work, a flow field model of WC–12Co powder sprayed by high‐velocity air fuel (HVAF) was established based on the computational fluid dynamics (CFD) method. The macro–micro coupled thermodynamic model of coating multilayer growth process was established based on the birth and death element method. The temperature and velocity of the particles in the combustion flame were applied to the coating growth model, and the transient evolution of the coating temperature and thermal stress was revealed. The results show the temperature and thermal stress of coatings increase with the increasing the number of spraying layers, and their incremental gradient gradually decreases with the increasing the number of deposition layers. The peak temperature of the coating surface reaches 1494 K, and the peak thermal stress of the first coating reaches 2693 MPa. The maximum stress of spraying particles appears at the contact edge of particles. Further preparation of WC coating, through the hardness, friction, and wear, corrosion tests verify that WC–12Co coating can effectively provide the TC18 substrate performance. The microhardness of WC–12Co coating was approximately three times that of TC18 substrate. The average friction coefficient and corrosion rate of the coating are 0.15 and 0.06 mg/cm2/h lower than that of the substrate, respectively. [ABSTRACT FROM AUTHOR]

This study investigates the effects of film thickness and substrate bias on the microstructure and stress state of tungsten (W) films prepared by arc ion plating (AIP) on substrates including 304 stainless steel (SS), tungsten (W), and Si (100). The microstructure of the films was characterized using X-ray diffraction (XRD) and field emission scanning electron microscopy (FE-SEM). Residual stress was analyzed using substrate curvature techniques combined with Stoney's formula and Huseh's formula. The results indicate that the W films are single-phase, predominantly comprising the pure α-phase. The film surfaces are dense and smooth, with the absence of large particles. The films consist of closely packed columnar grains, and no microcracks, voids, or delamination were observed at the film-substrate interface, indicating strong adhesion. As the film thickness increased, the curvature of the W/SS system and the compressive stress in the film both increased, which closely matched the fitted curves. As the substrate bias increased, the curvature of the W/SS system decreased, and the compressive stress in the W film increased. At higher substrate biases, deposition temperatures are higher, and growth stress remains nearly constant across a range of continuous bias variations, with the increase in residual stress primarily due to thermal stress. [ABSTRACT FROM AUTHOR]