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The magnetic performance of NdFeB permanent magnets rapidly decreases as their operation temperature increases. This limits the power output of electric motors as their internal temperature quickly increases with the power demand. This is particularly problematic for applications where high peak power is required for a short period of time, for example during automobile highway acceleration or during an airplane lift-off. With the advances in additive manufacturing, one can envision to fabricate more complex motor geometries and magnetic structures, without additional costs, allowing for enhanced functionalities such as better thermal management. In this context, this paper investigates the feasibility of using phase changing materials (PCMs) to mitigate the temperature rise in permanent magnets (PMs) fabricated by additive manufacturing. The potential of PCM and its relevance was validated by modeling the thermal response of an electric motor during a representative electric vehicle driving scenario. It was found that segmented magnets with embedded phase changing materials would allow to efficiently control temperature rise. To validate the simulation results, PM test pieces with and without embedded PCMs were fabricated using cold spray additive manufacturing and tested using a custom laser thermal cycling setup. [ABSTRACT FROM AUTHOR]

The correlated semiconductor vanadium dioxide (VO2) exhibits an insulator–metal transition (IMT) near room temperature, which is of interest in various device applications. Precise IMT temperature control is crucial to determine the use cases across technologies such as thermochromic windows, actuators for robots or neuronal oscillators. Doping the cation or anion sites can modulate the IMT by several tens of degrees and control hysteresis. However, modeling the effects of control parameters (e.g., doping concentration, type of dopants) is challenging due to complex experimental procedures and limited data, hindering the use of traditional data-driven machine learning approaches. Symbolic regression (SR) can bridge this gap by identifying nonlinear expressions connecting key input parameters to target properties, even with small data sets. In this work, we develop SR models to capture the IMT trends in VO2 influenced by different dopant parameters. Using experimental data from the literature, our study reveals a dual nature of the IMT temperature with varying tungsten (W) doping concentrations. The symbolic model captures data trends and accounts for experimental variability, providing a complementary approach to first-principles calculations. Our feature-driven analysis across a broader class of dopants informs selectivity and provides qualitative insights into tuning phase transition properties valuable for neuromorphic computing and thermochromic windows. [ABSTRACT FROM AUTHOR]

This study reports light narrowing in paraffin-coated vapor cells from room temperature 27 to 59 °C, where spin-exchange relaxation is suppressed. By means of a coating lock and eliminating the reservoir effect, an ultra-narrow magnetic resonance linewidth of 0.36 Hz and an atomic coherence lifetime of T 2 = 0.9 s are achieved. In cells free of buffer gas, the narrow linewidth over this broad temperature range is a result of enhanced spin polarization, which is facilitated by the effective suppression of radiation trapping benefiting from the stability of the vapor density. Using such cells in atomic magnetometers, the photon shot noise limit is estimated as 0.2 fT / Hz 1 / 2 and the spin-projection noise limit is estimated as 1.1 fT / Hz 1 / 2 . Also, a magnetometer system with the stable coated cell is identified, which demonstrates the potential for achieving relatively stable magnetometer sensitivity without precisely controlling the cell temperature. The long coherence lifetime and the broad operating temperature range expand the potential applications of quantum memory and other quantum sensors such as atomic clocks. [ABSTRACT FROM AUTHOR]

An accurate and efficient heat bath method plays a key role in atomic simulations of the thermal and mechanical properties of single-crystal silicon. Here, focusing on the single-crystal silicon (111) layer, which is a crucial lattice structure commonly employed as a substrate for chips, we propose a heat jet approach for finite temperature atomic simulations of silicon layers. First, we formulate the linearized dynamic equations for the silicon atoms and calculate the dispersion relation and lattice wave solutions. Then, an appropriate matching boundary condition is chosen for designing the two-way boundary condition, which allows incoming waves to inject into the lattice system while eliminating boundary reflections. Combining the two-way boundary condition and phonon heat source, the heat jet approach for the silicon (111) layer is proposed. Numerical tests illustrate the accuracy and effectiveness of the heat jet approach in simultaneously resolving thermal fluctuations and controlling temperature. Furthermore, we simulate the propagation of a Gaussian hump at a given temperature with the heat jet approach compared to the Nosé–Hoover heat bath. Numerical results demonstrate that the heat jet approach can well describe the movement of large structural deformations among thermal fluctuations without boundary reflections. [ABSTRACT FROM AUTHOR]

We examine structural and magnetic properties of a series of La–Fe–Si alloys in the region of concentrations where they naturally form two-phase LaFeSi–LaFe13−xSix composites with variable content and connectivity of LaFe13−xSix grains distributed within the LaFeSi matrix. Theoretical calculations confirm that the LaFeSi constituent is magnetically and structurally inert below room temperature and at pressures between −10 and 10 GPa. The LaFe13−xSix constituent, on the other hand, is magnetically and structurally active: it exhibits first-order magnetostructural transformations that, in addition to xSi, can be controlled with temperature, magnetic field, and pressure. In composites where the concentration of the inactive constituent is ∼70 wt. % or greater, the standard, single-step, LaFe13−xSix first-order phase transformation proceeds in two steps separated by over 30 K in a zero magnetic field. Increasing the magnetic field recouples the two steps and restores the single-step phase transformation pathway. We analyze the roles of stresses caused by both thermal expansion mismatch and the first-order magnetic phase transition in LaFe13−xSix to rationalize the observed physical behaviors that emerge as the temperature or/and magnetic field vary. [ABSTRACT FROM AUTHOR]

Thermoelectric coolers (TECs) offer a promising solution for direct cooling of local hotspots and active thermal management in advanced electronic systems. However, TECs present significant trade-offs among spatial cooling, heating, and power consumption. The optimization of TECs requires extensive simulations, which are impractical for managing actual systems with multiple hotspots under spatial and temporal variations. In this study, we present a novel machine learning-assisted optimization algorithm for thermoelectric coolers that can achieve global optimal temperature by individually controlling TEC units based on real-time multi-hotspot conditions across the entire domain. We train a convolutional neural network with a combination of the inception module and multi-task learning approach to comprehend the coupled thermal-electrical physics underlying the system and attain accurate predictions for both temperature and power consumption with and without TECs. Due to the intricate interaction among passive thermal gradient, Peltier effect and Joule effect, a local optimal TEC control experiences spatial temperature trade-off which may not lead to a global optimal solution. To address this issue, we develop a backtracking-based optimization algorithm using the machine learning model to iterate all possible TEC assignments for attaining global optimal solutions. For any m × n matrix with NHS hotspots (n, m ≤ 10, 1 ≤ NHS ≤ 20), our algorithm is capable of providing 52.4% peak temperature reduction and its corresponding TEC array control within an average of 1.64 s while iterating through tens of temperature predictions behind-the-scenes. This represents a speed increase of over three orders of magnitude compared to traditional finite element method strategies which take approximately 27 min. [ABSTRACT FROM AUTHOR]

Enhanced sampling algorithms are indispensable when working with highly disconnected multimodal distributions. An important application of these is the conformational exploration of particular internal degrees of freedom of molecular systems. However, despite the existence of many commonly used enhanced sampling algorithms to explore these internal motions, they often rely on system-dependent parameters, which negatively impact efficiency and reproducibility. Here, we present fully adaptive simulated tempering (FAST), a variation of the irreversible simulated tempering algorithm, which continuously optimizes the number, parameters, and weights of intermediate distributions to achieve maximally fast traversal over a space defined by the change in a predefined thermodynamic control variable such as temperature or an alchemical smoothing parameter. This work builds on a number of previously published methods, such as sequential Monte Carlo, and introduces a novel parameter optimization procedure that can, in principle, be used in any expanded ensemble algorithms. This method is validated by being applied on a number of different molecular systems with high torsional kinetic barriers. We also consider two different soft-core potentials during the interpolation procedure and compare their performance. We conclude that FAST is a highly efficient algorithm, which improves simulation reproducibility and can be successfully used in a variety of settings with the same initial hyperparameters. [ABSTRACT FROM AUTHOR]

PtS2, a member of the group 10 transition metal dichalcogenides (TMDs), has received extensive attention because of its excellent electrical properties and air stability. However, there are few reports on the preparation of single-crystal PtS2 in the literature, and the growth mechanism of single crystal PtS2 is not well elucidated. In this work, we proposed a method of preparation that combines magnetron sputtering and chemical vapor transport to obtain monocrystalline PtS2 on a SiO2/Si substrate. By controlling the growth temperature and time, we have synthesized a single crystalline PtS2 of hexagonal shape and size of 1–2 μm on a silicon substrate. Combining the molecular dynamics simulation, the growth mechanism of single crystal PtS2 was investigated both experimentally and theoretically. The synthesis method has a short production cycle and low cost, which opens the door for the fabrication of other TMDs single crystals. [ABSTRACT FROM AUTHOR]

We demonstrate modulation of insulator metal transition (IMT) of VO2 films grown on single crystalline substrates through the effect of in-plane compression with crystallization of capping chalcogenide layer on the targeted VO2 films. Chalcogenide germanium–antimony–telluride (Ge2Sb2Te5: GST), which shows large volume reduction of 6.8% with its phase change from amorphous to crystal, was deposited on VO2 films grown on Al2O3 (001) and TiO2 (001) substrates, where V–V atoms along the cR-axis in the tetragonal VO2 phase align parallel and perpendicular to the substrate surfaces, respectively. As a result, counter shifts in temperature-dependence of resistance characteristics, to lower and higher directions, were observed for VO2 films on Al2O3 (001) and TiO2 (001), consistent with the lattice modulation of VO2 films by the in-plane compression introduced by GST crystallization. The obtained results open a way to realize large resistance change of IMT under constant temperature by controlling GST phases. [ABSTRACT FROM AUTHOR]

Understanding and modulating the spin-pair correlation of conjugated polymer materials in π-conjugated polymer light-emitting devices (PLEDs) plays a crucial role in the development of their applications. We investigated the relationships between the internal hyperfine interactions (HFIs), triplet–triplet annihilation (TTA), and triplet–charge annihilation (TCA) spin evolution processes in π-conjugated PLED. Research has shown that in a unipolar π-conjugated PLED, the "M" shaped ultra-small magnetic field effect is due to the HFI between hole polarons and the spin-mixing process of charge carriers. Under high magnetic fields (15 mT<|B|<350 mT), the TCA process dominates the negative magneto-conductance (MC), and its intensity and sign are not controlled by temperature. In polar π-conjugated PLED, excess carriers can provide conditions for the generation of TCA. Moreover, π-conjugated polymers (emission layers) have relatively strong electron–phonon coupling, which can capture triplet excitons into adjacent organic layers to obtain higher triplet exciton concentrations, resulting in the TTA process. Under low-temperature conditions, excess carriers induce the magneto-electroluminescence (MEL) effect to undergo TTA and form P-type delayed fluorescence. This study can provide a new mechanism explanation for the HFI in PLED devices and a new approach for the effective utilization of triplets. [ABSTRACT FROM AUTHOR]

Molecular dynamics simulations have been widely used in exploring the nucleation behavior of many systems, including gas hydrates. Gas hydrates are ice-like solids in which gas molecules are trapped in water cages. During hydrate formation, a considerable amount of heat is released, and previous work has reported that the choice of temperature control scheme may affect the behavior of hydrate formation. The origins of this effect have remained an open question. To address this question, extensive NVE simulations and thermostatted (NPT and NVT) simulations with different temperature coupling strengths have been performed and compared for systems where a water nanodroplet is immersed in a H2S liquid. Detailed analysis of the hydrate structures and their mechanisms of formation has been carried out. Slower nucleation rates in NVE simulations in comparison to NPT simulations have been observed in agreement with previous studies. Probability distributions for various temperature measures along with their spatial distributions have been examined. Interestingly, a comparison of these temperature distributions reveals a small yet noticeable difference in the widths of the distributions for water. The somewhat reduced fluctuations in the temperature for the water species in the NVE simulations appear to be responsible for reducing the hydrate nucleation rate. We further conjecture that the NVE-impeded nucleation rate may be the result of the finite size of the surroundings (here the liquid H2S portion of the system). Additionally, a local spatial temperature gradient arising from the heat released during hydrate formation could not be detected. [ABSTRACT FROM AUTHOR]

To explore potential applications in classical and quantum information transfer, the hybrid systems between yttrium iron garnet (YIG) and cavities have been extensively studied, and four coupling regimes have been defined based on the relative strength between the coupling strength and dissipation rate of each subsystem. Achieving the control of magnon–photon coupling between nano-thick YIG films and cavities remains to be explored. We experimentally measure the microwave transmission spectra of a nano-thick yttrium iron garnet/gadolinium gallium garnet (YIG/GGG) film coupled to a superconducting cavity at different temperatures. The dissipation rate of the superconducting cavity increases significantly with decreasing temperature, which is influenced by the temperature-dependent magnetic susceptibility of the GGG substrate. Accompanied by the temperature-dependent magnon dissipation rate, a continuous transformation of the coupled system in strong coupling, Purcell and weak coupling regimes is achieved. [ABSTRACT FROM AUTHOR]

Ensuring food safety and quality is paramount for consumers. Water, a fundamental component of food, exhibits diverse crystalline structures under high pressure (HP) and experiences alterations in freezing points. Exploiting these water characteristics has spurred the development of innovative high-pressure sub-zero temperature (HPST) techniques. This review systematically categorizes HPST technologies based on their adherence to the temperature-pressure phase diagram, encompassing high-pressure freezing (HPF), high-pressure thawing (HPT), solid-solid phase transition (SSPT) treatment, and isochoric freezing (IF). Furthermore, the review elaborates on the latest advancements in HP cryogenic equipment, focusing on temperature and pressure control units. The underlying principles of the HPST technologies and their inactivation effects on various food materials, such as beverages and meat, are elaborated, and the effects of the HPST treatments on the appearance, texture, moisture content, and other quality characteristics of the food products are discussed. Emphasis is placed on delineating the advantages, disadvantages, and application scopes of different HPST technologies. To propel comprehensive research and foster the industrialization of HPST technology, future endeavors should concentrate on validating the commercial viability of HP cryogenic equipment, establishing dependable temperature regulation and detection systems, and compiling a comprehensive melting point database for real food under HP conditions. [ABSTRACT FROM AUTHOR]

The temperature coefficient of dielectric constant (τ ε) is a crucial parameter for assessing the performance stability of microwave devices operating under varying temperature conditions. In this study, polyphenylene oxide (PPO) resin was utilized as the matrix and six types of ceramics with distinct temperature coefficients of dielectric constant were employed as fillers. Six PPO-based composites were fabricated through twin-screw extrusion combined with hot pressing route. The dielectric properties of the ceramics and their influence on the dielectric properties of the composites, particularly the τ ε , were systematically investigated. The results revealed that all six types of composites exhibited dense structures and uniform filler distribution, with a relative density exceeding 98.0 % and a water absorption below 0.1 %. The dielectric constant and its temperature coefficient of the fillers had a more pronounced effect on the dielectric properties of the composites, compared to dielectric loss. The dielectric constants of the six types of composites aligned well with the theoretical values predicted by the effective medium theory. Reaching up to 9.7 (at 10 GHz). The dielectric loss ranged from 1.0 × 10−3 to 3.0 × 10−3. Notably, the PPO/Mg 0.95 Ca 0.05 TiO 3 composite substrate with a filler ratio of 40 vol% exhibited exceptional dielectric properties: ε r = 6.8, tg δ = 1.4 × 10−3, τ ε = −8.6 ppm/°C, highlighting its significant advantages for communication applications under varying temperature conditions. [ABSTRACT FROM AUTHOR]

'Thermal governance' has been discussed elsewhere as the regulation of temperature through infrastructure, technology and social and political organisation. We extend it here to include a subtle and heretofore under-recognised element of public health: the governance of recent urban epidemics by the Chinese state. The SARS epidemic of 2002–2003 in Guangzhou and more markedly the COVID-19 epidemic in Wuhan triggered massive emergency responses by public health authorities which differed from previous strategies in more fully activating the state health sector known in China as Chinese Medicine (zhongyi) and outside China as Traditional Chinese Medicine. With this enlistment comes a body of theory and practice which makes meteorology central to diagnostic and prescriptive processes, and reinforces as part of state discourse the long-standing Chinese cultural understanding of 'heat' as an internal micro-climatic element transcending temperature. [ABSTRACT FROM AUTHOR]

Objective. A reliable, calibrated, non-invasive thermometry method is essential for thermal therapies to monitor and control the treatment. Ultrasound (US) is an effective thermometry modality due to its relatively high sensitivity to temperature changes, and fast data acquisition and processing capabilities. Approach. In this work, the change in backscattered energy (CBE) was used to control the tissue temperature non-invasively using a real-time proportional-integral-derivative (PID) controller. A clinical high-frequency US scanner was used to acquire radio-frequency echo data from ex vivo porcine tissue samples and in vivo mice hind leg tissue while the tissue was treated with mild hyperthermia by a focused US applicator. The PID controller maintained the focal temperature at approximately 40 °C for about 4 min. Main results. The results show that the US thermometry based on CBE estimated by a high-frequency US scanner can produce 2D temperature maps of a localized heating region and to estimate the focal temperature during mild hyperthermia treatments. The CBE estimated temperature varied by an average of ±0.85 °C and ±0.97 °C, compared to a calibrated thermocouple, in ex vivo and in vivo studies, respectively. The mean absolute deviations of CBE thermometry during the controlled hyperthermia treatment were ±0.45 °C and ±0.54 °C in ex vivo and in vivo, respectively. Significance. It is concluded that non-invasive US thermometry via backscattered energies at high frequencies can be used for real-time monitoring and control of hyperthermia treatments with acceptable accuracy. This provides a foundation for an US mediated drug delivery system. [ABSTRACT FROM AUTHOR]

Microstructure arrays are the basis for micro-optical systems. This paper presents a roll-to-plate (R2P) hot embossing method and process equipment that are developed for precision manufacturing of glass microstructures. The surface crack generation and deformation mechanism of glass in R2P hot embossing process are analyzed. A temperature control method and an elastic clamping fixture are developed to avoid warping and cracking of the glass workpiece. Surface microstructures are successfully replicated to glass through R2P hot embossing. Experimental results show high fidelity and good uniformity between the microstructure patterned plate mould and the workpiece. The forming ability increases with increasing embossing temperature and loading displacements, and decreasing mould feed rate. The results demonstrate that the R2P hot embossing process is effective for the precision manufacturing of large-area micro-structured surfaces on glass. [ABSTRACT FROM AUTHOR]

Crystallization-controlled structure and thermal properties of biobased poly(ethylene 2,5-furandicarboxylate) (PEF) were studied. The cold-crystallization temperature controlled the structure and thermal properties of the biobased PEF. The melting was complex and evidenced the presence of a significant fraction of less-stable crystals with a low melting temperature that linearly increased with Tc, which formed already during the early stages of crystallization, together with those melting at a higher temperature. Low Tc resulted in the α'-phase formation, less crystallinity, and greater content of the rigid amorphous phase. At high Tc, the α-phase formed, higher crystallinity developed, the rigid amorphous phase content was lower, and the melting temperature of the less-stable crystals was higher; however, slight polymer degradation could have occurred. The applied thermal treatment altered the thermal behavior of PEF by shifting the melting of the less stable crystals to a significantly higher temperature. SEM examination revealed a spherulitic morphology. A lamellar order was evidenced with an average long period and small average lamella thickness, the latter about 3–3.5 nm, only slightly increasing with Tc. [ABSTRACT FROM AUTHOR]

Fabrication of dielectrics at low temperature is required for temperature-sensitive detectors. For superconducting detectors, such as transition edge sensors and kinetic inductance detectors, AlMn is widely studied due to its variable superconducting transition temperature at different baking temperatures. Experimentally only the highest baking temperature determines AlMn transition temperature, so we need to control the wafer temperature during the whole process. In general, the highest process temperature happens during dielectric fabrication. Here, we present the cryogenic microwave performance of Si 3 N 4 , SiN x and α -Si using ICPCVD at low temperature of 75 ∘ C. The dielectric constant, internal quality factor and TLS properties are studied using Al parallel plate resonators. [ABSTRACT FROM AUTHOR]

Thermal runaway is a frequent source of process safety issues, and the uncontrolled release of chemical energy puts reactors at risk. The design of the exothermic reactor faces challenges due to the selective sensitivity of the product to high temperatures and the need to increase the lifetime of the catalyst, optimize the product distribution, and improve the thermodynamic properties. Phase change material (PCM) encapsulation is recommended to reduce leakage, phase separation, and volume change problems. This work introduces encapsulated PCMs to improve reactor temperature control and minimize thermal runaway in exothermic processes. The warning temperature value setting effectively inhibits fugitive exothermic reactions and enhances heat transfer. When a sufficient quantity of encapsulated PCMs is input, the response speed will automatically accelerate. Spontaneous acceleration of the reaction rate due to thermal runaway of the reaction may be completely avoided by adding a sufficient amount of encapsulated PCM. Microencapsulation is used to control volume changes and inhibit thermal reactions. Preventive strategies include cooling, depressurization, safety release, emergency resources, and reaction containment. Encapsulated PCMs improve mechanical and thermal properties, surface-to-volume ratio, heat transfer surface, thermal capacity, and efficiency. [ABSTRACT FROM AUTHOR]

In order to obtain a building thermal storage material with excellent thermal performance, sufficient strength and low leakage, the advantages of ternary PCMs (Lauric acid—Palmitic acid—Tetradecyl alcohol, LA-PA-TA) and vitrified beads (VB) as a adsorbent carrier were integrated to prepare a novel LA-PA-TA/VB composite PCM which exhibited favorable phase change temperature (i.e. 20.1–20.5°C) and low sub-cooling (0.4°C). Then, the novel LA-PA-TA/VB was, respectively, encapsulated with five different materials (a true stone paint emulsion, styrene-acrylic emulsion, EVA emulsion, epoxy resin and cement powder) to form a shape-stabilized LA-PA-TA/VB (SS-LA-PA-TA/VB) in order to reduce the leakage. The mass loss and mechanical properties experiments showed that SS-LA-PA-TA/VB encapsulated with the real stone paint emulsion-cement powder presented the optimal stability and reliability with low mass loss ratio of only 2.67% after 50 phase change cycles. The SS-LA-PA-TA/VB with the optimal package was further prepared into a thermal energy storage mortar (TESM) with different SS-LA-PA-TA/VB contents. The results show that the thermal properties of the TESM increased and the mechanical properties decreased with SS-LA-PA-TA/VB contents. However, even with the TESM with 30 wt% SS-LA-PA-TA/VB (30TESM), the compressive strength, flexural strength etc. still satisfy the requirement of the Chinese National Standard. The analysis shows that the hydrophobic functional groups are attached to the surface of the emulsion of the real stone paint, whereby a stable hydrophobic film was formed. In addition, the temperature regular ability and heat insulation performance of 30TESM and the referenced mortar were compared by temperature probe embedded inside the mortar blocks and installed in a small experimental room. The results indicated that the internal temperature of the mortar blocks, backside and central temperature in the small room was 5.4°C,5.6°C and 2.1°C lower than those of the referenced group, respectively. It is thus clear that the novel low cost TESM exhibits a good temperature damping effect and temperature control performance and may have a widespread application in the areas of building energy conservation. [ABSTRACT FROM AUTHOR]

We demonstrate an all-fiber oscillator with high optical-to-optical efficiency using laser diodes working at 915nm as the pump sources to reduce the demand for thermal management. When the output power of the bidirectional pumped oscillator is 1.16kW, the optical-to-optical efficiency is as high as 75.4%. In this working state, the output characteristics of the oscillator are observed. The Raman suppression ratio is 41.23dB and the beam quality factor Mx2 = 1.14, My2 = 1.29. Analyzing the time trajectory of the highest power output, there are no significant characteristic peaks in the time domain signal and the frequency domain signal, which indicates that the oscillator has good stability.Improving the output characteristics of the 915nm pumping lasers has a positive significance for the application of non-strict ambient temperature control. [ABSTRACT FROM AUTHOR]

Irradiation from the central star controls the temperature structure in protoplanetary discs. Yet simulations of gravitational instability typically use models of stellar irradiation with varying complexity, or ignore it altogether, assuming heat generated by spiral shocks is balanced by cooling, leading to a self-regulated state. In this paper, we perform simulations of irradiated, gravitationally unstable protoplanetary discs using 3D hydrodynamics coupled with live Monte-Carlo radiative transfer. We find that the resulting temperature profile is approximately constant in time, since the thermal effects of the star dominate. Hence, the disc cannot regulate gravitational instabilities by adjusting the temperatures in the disc. In a |$0.1M_\odot$| disc, the disc instead adjusts by angular momentum transport induced by the spiral arms, leading to steadily decreasing surface density, and hence quenching of the instability. Thus, strong spiral arms caused by self-gravity would not persist for longer than ten thousand years in the absence of fresh infall, although weak spiral structures remain present over longer time-scales. Using synthetic images at 1.3 mm, we find that spirals formed in irradiated discs are challenging to detect. In higher mass discs, we find that fragmentation is likely because the dominant stellar irradiation overwhelms the stabilizing influence of |$P\mathrm{d}V$| work and shock heating in the spiral arms. [ABSTRACT FROM AUTHOR]

Double emulsion consists of two interfacial layers which can encapsulate both hydrophilic and lipophilic substances within a single carrier. Besides encapsulation, double emulsion has also been used to modify the sensorial properties of food products. However, at the same time, double emulsion is susceptible to destabilization under environmental stresses and long-term storage. In this paper, recent articles on double emulsion were critically highlighted in terms of production, composition, and stabilization. With current existing fundamental knowledge about double emulsion, this paper aims to review the utilization of double emulsion for food application to bring potential benefits, stability, and future application. The stability of double emulsion during production and storage was affected by the production method, composition, and temperature control. In terms of food application, double emulsion has been successfully applied in fat-reducing products, food encapsulation, fortification, preservation, edible food packaging, etc. The recent insights in forming stable storage of double emulsion with food-grade emulsifiers have also been discussed in this review paper. In the future, the efforts in mitigating the destabilization behaviour of double emulsion might be beneficial in boosting the applications of double emulsion in bigger markets. [ABSTRACT FROM AUTHOR]

• A numerical simulation was conducted to analyze the susceptibility to crosswinds during the spraying of the air cooler. • The flow field temperature within the skid-mounted CNG air cooler when subjected to crosswind conditions was analyzed. • The installation of baffles enhances the air intake of the cooler, which effectively eliminates the adverse effects of ambient wind. Air cooler is a critical heat dissipation equipment applied in the field of oil and gas storage, which is mainly used to control the temperature during oil and gas storage and ensure the safety of oil and gas storage. After the installation of the spray cooling system on the skid-mounted compressed natural gas (CNG) air cooler Suqiao gas storage, the inlet air temperature of the air cooler decreases, resulting in reduced compressor power consumption. This effectively addresses the issue of unit shutdown due to high temperatures during the summer. However, the actual spray effect on-site reveals the impact of crosswinds, which poses a challenge. In this study, the flow field and causes of the skid-mounted CNG air cooler equipped with a spray cooling system under the influence of crosswinds are analyzed. Additionally, a solution involving the installation of a baffle is proposed. The results highlight that crosswinds have an adverse effect on outdoor spray cooling. With the installation of the baffle, the low-temperature area expands, resulting in lower temperatures. The cooling range is approximately 2 K, effectively counteracting the negative effects of crosswinds. [ABSTRACT FROM AUTHOR]

To improve energy conservation and reduce emissions of an engine, this study applies intelligent thermal management to a cooling system. With a marine high-speed diesel engine as the research object, an intelligent cooling system based on controllable cooling components was developed. A variable-universe fuzzy control algorithm is designed to control an electronic thermostat, and a 'T–S fuzzy control + BP-PID' control algorithm is proposed to control standard electric drive pumps. The experimental results indicate that the intelligent cooling system considerably reduces the warm-up time, achieves accurate cooling, and effectively inhibits the hot immersion phenomenon. The intelligent control algorithm has control characteristics such as rapid response, strong adaptive ability, small overshoot, smooth transition, and high precision. The intelligent cooling system reduced the cooling-system power consumption by 5.52%–57.93%, fuel consumption rate by 1.43%–5.15%, smoke emission by 1.40%–4.69%, CO emission by 2.14%–6.03%, and HC emission by 7.41%–12.26%. [ABSTRACT FROM AUTHOR]

This paper maps the supply, demand, and budget of five ecosystem services (ESs) based on land use/cover data classified for the Little Akaki River catchment in central Ethiopia, which include urban and peri-urban areas. For land use characterization, we used a recently introduced method of mapping urban morphology types (UMTs), followed by land cover analysis (within the identified UMTs) for 2006 and 2016 by distributing sample points randomly over the extent of each UMT. Additionally, ecosystem service supply and demand data were collected using expert assessment. The UMT maps revealed 14 primary and 38 sub-UMTs for 2006 and 14 primary and 41 sub-UMTs for 2016. From primary UMTs, agriculture UMT (37%) in 2006 and residential UMT (32%) in 2016 are dominant, revealing a recently increasing transformation of UMTs into residential UMTs. The land cover change analysis shows a decrease in evapotranspiring surfaces (from 46% in 2006 to 32% in 2016) and an increase in built surfaces (from 24% in 2006 to 32% in 2016), indicating rapid urbanization within the catchment that will possibly lead to degradation of ESs. The ESs capacity map shows that agriculture UMTs deliver very high relevant food and high relevant capacity for flood regulation. Vegetation UMT shows very high relevant capacity for temperature regulation, recreation UMT for recreation service, and waterbodies for water supply. Overall, this paper demonstrated that rapid urbanization at the expense of ecologically essential land covers most likely degrade ESs in the Little Akaki River catchment, contributing to the global ecosystem service degradation and climate change. Hence, we highly recommend the application of green infrastructure planning that protects evapotranspiring surfaces that supply multiple ESs in the catchment. This in addition contributes to the global effort to protect green spaces that supplies multiple ecosystem service. [ABSTRACT FROM AUTHOR]

This review highlights the critical effects of heat transfer and bubble mass transfer in alkaline water electrolysis on hydrogen generation efficiency. To improve heat transfer performance, the study focuses on reducing electrical resistance and controlling the electrolysis system's temperature. It proposes innovative strategies such as using metal matrix composites and catalysts to optimize electrode structure, precise temperature and pressure regulation and enhanced electrolyte concentration. Additionally, the study examines the dynamics of bubble mass transfer, proposing effective strategies to reduce bubble coverage, including hydrophilic electrodes, mechanically circulating the electrolyte and voltage smoothing with pressure swinging. This study contributes to the advancement of hydrogen energy technology with practical strategies. By adjusting the electrolysis system to optimize the combined effect of these factors, we can improve the efficiency, economy and environmental friendliness of hydrogen production. This will contribute to the transformation of the global energy mix and the implementation of sustainable development strategies. [ABSTRACT FROM AUTHOR]

Soft robots have excellent spatial adaptability and high flexibility, but they are limited by the low stiffness of their constituent materials when faced with high‐load tasks. In recent years, there have been many works on the development of stiffness‐tunable soft actuators by introducing variable stiffness materials into soft actuators, but the existing solutions usually suffer from the problems of slow response, complex structure, and the need of many auxiliary devices to support the completion of the stiffness tuning cycle. This paper proposes a tendon‐driven stiffness‐tunable soft actuator that addresses these issues. Benefiting from the bidirectional temperature control of thermoelectric modules and the excellent in‐plane thermal conductivity of graphene, the actuator is capable of achieving the heating and cooling process by transferring the heat flow through the graphene structure into and out of the shape‐memory polymer (SMP) layer of the tendon‐driven actuator. This enables stiffness tuning via a single device, reducing the dependence on complex external cooling systems. The use of tendon‐driven actuators further eliminates the complex bellow structure of conventional pneumatic actuators and dramatically reduces the size and manufacturing difficulty of individual actuators. Finally, the high load capacity and shape adaptability of the actuator are demonstrated by a gripper equipped with three actuators, which successfully grips objects of various shapes and weights, ranging from less than 10 g to up to 1.6 kg. [ABSTRACT FROM AUTHOR]

The complex heat transfer processes occurring in a magnetized water‐based hybrid nanofluid flowing past a stretching or shrinking wedge are investigated in this work. The research highlights the significant influence of the wedge angle on fluid flow patterns and temperature gradients, emphasizing how larger angles cause changes in pressure, flow separation, and temperature profiles. Additionally, the study emphasizes the importance of radiation effects near surfaces, where increased radiation often leads to cooling due to thermal energy emission. The findings have implications in industries such as aerospace, electronics, thermal management, and groundwater resources management where precise temperature control is critical for safe and efficient operations. The numerical method applied to solve the governing equations in the study is the fourth‐order Runge–Kutta technique with shooting technique. This method efficiently solves the boundary value problem by converting it into a system of first‐order initial value problems. Then shooting technique is used to solve the system, starting with an adequate initial guess. The study's results are presented in tabular and graphical forms, providing valuable insights into the complex fluid dynamics and thermal behavior in the given setting, enabling more informed decision‐making and optimization in relevant engineering applications. Increased radiation frequently results in a cooling effect owing to thermal energy output. Heat sinks/heat sources are crucial in temperature regulation and are effective in lowering temperatures via processes. We also emphasize the importance of radiation impacts near surfaces, where increased radiation frequently leads to cooling owing to thermal energy emission. The numerical values of skin friction and Nusselt number for various parameters in the cases of shrinking and stretching provide crucial insights into the heat transmission and frictional properties of the system under examination. These quantitative results contribute to a better understanding of the complex fluid dynamics and thermal behavior in the given setting, emphasizing the significance of the research findings. [ABSTRACT FROM AUTHOR]

Introduction: Indoor cycling at home has grown rapidly in recent years facilitated by advances in technology and gamification. However, there is limited data on individual's training practices when cycling indoors. Methods: Using a single-time point, cross-sectional questionnaire, we gathered information on equipment, environmental considerations, training practices and nutrition during indoor cycling. Results: Following 492 responses, external variables (weather; 88.4%, lack of daylight; 56.3%), time efficiency (81.9%) and general fitness (70.9%) were most frequently cited as reasons to engage in indoor cycling. "Smart" turbo trainers linked to a mixed-reality cycling software were most frequently reported in equipment set-up. 78% of participants attempted to control temperature with 96% of these participants using at least 1 fan to control airflow. The volume of indoor training differed between seasons (winter: 6h10 ± 3 h 30, summer 2h52 ± 2h57, p < 0.001), and structured (61.9%) and unstructured work-outs (64.7%) were completed more than once a week with fewer participants engaging in competitive/racing events (20.9%). 98% percent of participants consumed fluids with an average fluid intake of 0.74 ± 0.28 L/h. Dependent on type of work-out, participants reported less planning of carbohydrate and protein intake during short-duration work-outs (~40%-60%) relative to longer-duration work-outs (~56%-80%). Caffeine use was the most frequently reported ergogenic aid. Conclusion: Together we report indoor cycling practices with respect to training equipment, considerations of environmental and nutritional strategies and training habits. Our findings could be used to support the development of future research and indoor training guidelines. [ABSTRACT FROM AUTHOR]

ABSTRACT Traditional photosynthesis‐driven growth models have considerable uncertainties in predicting tree growth under changing climates, partially because sink activities are directly affected by the environment but not adequately addressed in growth modelling. Therefore, we developed a semi‐mechanistic model coupling stomatal optimality, temperature control of enzymatic activities and phenology of cambial growth. Parameterized using Bayesian inference and measured data on Picea abies and Pinus sylvestris in peatland and mineral soils in Finland, the coupled model simulates transpiration and assimilation rates and stem radial dimension (SRD) simultaneously at 30 min resolution. The results suggest that both the sink and phenological formulations with environmental effects are indispensable for capturing SRD dynamics across hourly to seasonal scales. Simulated using the model, growth was more sensitive than assimilation to temperature and soil water, suggesting carbon gain is not driving growth at the current temporal scale. Also, leaf‐specific production was occasionally positively correlated with growth duration but not with growth onset timing or annual cambial area increment. Thus, as it is hardly explained by carbon gain, phenology itself should be included in sink‐driven growth models of the trees in the boreal zone and possibly other environments where sink activities and photosynthesis are both restrained by harsh conditions. [ABSTRACT FROM AUTHOR]

Small-scale pumps for controlling microfluidics have promising applications in drug delivery and chemical assays. Liquid metal (LM) demonstrates excellent flow pumping performance due to its simple structure and the electrocapillary effect under an electric field. However, LM droplets risk escaping from constrained structures, which can lead to pump failure. Temperature regulation is also a critical parameter in optimizing chemical reactions in fluidic systems, however, integrating it into a compact system remains challenging. Here, we develop a temperature-triggered gallium-based actuator (TTGA) by introducing a gallium (Ga) droplet wetted on a copper (Cu) plate as the core element for flow actuation. The Cu plate prevents the Ga droplet from escaping the chamber and significantly increases the flow rate. By leveraging the electrochemical method to inhibit the supercooling effect of Ga, the TTGA enables activation/deactivation for flow actuation at different temperatures. We investigate the impact of electrode position, solution concentration, and applied voltage on TTGA’s pumping efficiency. By dynamically tuning the Ga droplet’s temperature to control phase transition, TTGA allows for accurate flow actuation control. Furthermore, placing Ga and eutectic Ga-indium (EGaIn) droplets in different channels enables the expected flow divergence for fluids with different temperatures. The development of TTGA presents new opportunities in microfluidics and biomedical treatment. [ABSTRACT FROM AUTHOR]

Van der Waals (vdW) heterojunctions composed of GaN/graphene have high transmittance and excellent carrier transport properties. The combination of multidimensional hybrid heterojunctions with metasurfaces can open up many fascinating prospects for novel optical components over a broad range of the electromagnetic spectrum. This work experimentally demonstrates a multifunctional temperature‐sensitive meta‐device based on GaN/graphene vdW heterojunctions integrated with a metasurface. Notably, it is discovered that the conductivity of the vdW heterojunctions increases rapidly when it is excited by a thermal signal, resulting in a significant change in the relative phase retardation as well as amplitude modulation of an incident THz wave. Then a continuous wavelet transform is used instead of the traditional Fourier transform, and the two‐dimensional wavelet coefficient card is built to achieve fast detection over a wider range of temperature. Simultaneously, the variation of temperature dynamically controls the contributions of the multipoles, eventually determining the active switching of exotic anapoles with extreme non‐radiative confinement to highly radiative electric dipoles. This work offers the possibility of designing novel chip‐scale multifunctional thermal tuning devices and promotes the potential application of active micro‐nanophotonic devices in temperature sensors, terahertz modulators, and dynamic near‐field imaging. [ABSTRACT FROM AUTHOR]

Synthetic duplexes with high stabilities have promising potential for mimicking biomolecular functions and developing supramolecular smart materials. Herein, we describe the synthesis and stimuli‐responsive properties of molecular duplexes derived from indolocarbazole–pyridine (I−P) oligomers. These duplexes adopt nonclassical helical structures, stabilized by I−P hydrogen‐bonding pairs in anhydrous chlorinated solvents. Notably, the longest duplex 62 (11‐mer)2 displays remarkable stability, forming twenty hydrogen bonds; its exchange energy barrier was determined to be ΔG≠=22.0 kcal ⋅ mol−1 at 75 °C in anhydrous (CDCl2)2. Upon the addition of water, a hydrated duplex 62 (11‐mer)2⊃10H2O was formed, with one water molecule inserted between each I−P hydrogen‐bonding pair. The Hill coefficient (n) for this process is 6.1, demonstrating extremely positive cooperativity. Conversely, the hydrated duplex 62 (11‐mer)2⊃10H2O was completely converted into the original anhydrous duplex 62 (11‐mer)2 when the temperature was increased. Interconversion between these two distinct duplexes can be repeatedly carried out by varying the temperature. Furthermore, reversible switching between hetero‐duplexes and homo‐duplexes was also demonstrated by controlling the temperature, with concomitant changes in the characteristic emission signals. [ABSTRACT FROM AUTHOR]

Isothermal nucleic acid amplification tests (NAATs) are a vital tool for point-of-care (POC) diagnostics. These assays are well-suited for rapid, low-cost POC diagnostics for infectious diseases compared to traditional PCR tests conducted in central laboratories. There has been significant development of POC NAATs using paper-based diagnostic devices because they provide an affordable, user-friendly, and easy to store format; however, the difficulties in integrating separate liquid components, resuspending dried reagents, and achieving a low limit of detection hinder their use in commercial applications. Several studies report low assay efficiencies, poor detection output, and poorer limits of detection in porous membranes compared to traditional tube-based protocols. Recombinase polymerase amplification is a rapid, isothermal NAAT that is highly suited for POC applications, but requires viscous reaction conditions that has poor performance when amplifying in a porous paper membrane. In this work, we show that we can dramatically improve the performance of membrane-based recombinase polymerase amplification (RPA) of HIV-1 DNA and viral RNA by employing a coin cell-based vibration mixing platform. We achieve a limit of detection of 12 copies of DNA per reaction, nearly 50% reduction in time to threshold (from ∼10 minutes to ∼5 minutes), and an overall fluorescence output increase up to 16-fold when compared to unmixed experiments. This active mixing strategy enables reactions where the target and reaction cofactors are isolated from each other prior to the reaction. We also demonstrate amplification using a low-cost vibration motor for both temperature control and mixing, without the requirement of any additional heating components. [ABSTRACT FROM AUTHOR]

In order to enhance the accuracy of temperature control of the patenting furnace, a new temperature control system (TCS) based on the fuzzy adaptive (FA)–proportion integral differential (PID) control algorithm is proposed. The system takes temperature error value and error rate as input and automatically adjusts the PID control parameter value according to the signal of the furnace temperatures to realize adaptive adjustment. Based on the parameter of the FA from simulations, the results of online application showed the temperature fluctuation reduced from 14 to 4°C in Zone I, and it decreased from 15 to 5°C in Zone II. Thus, the accuracy control of operational ability of the TCS was improved obviously. Following practical application, the microstructure analysis of the steel wire postpatenting demonstrated the creation of a more consistently distributed sorbite with enhanced properties by leveraging the new FA‐PID system. [ABSTRACT FROM AUTHOR]

While the rise in global ocean temperature continues its course, reaching 1.45+/- 0.12 °C above pre-industrial level according to the World Meteorological Organization in 2023, marine heat waves frequencies and intensities increase. Consequently, coral reef ecosystems which are among the most vulnerable environments are strongly impacted with dystrophic events and corals experiencing increasing frequencies of bleaching events. That has devastating consequences for the Pacific Island Countries and Territories (PICTS) that strongly rely on these ecosystems. In-situ observation remains the best alternative for providing accurate characterization of long-term trends and extremes in these shallow environments. This paper presents the coastal temperature dataset of the ReefTEMPS monitoring network in which moored stations are implemented over a number of PICTS over a wide region in the Western and Central South Pacific from New Caledonia to French Polynesia. These in situ temperature time series are unique in several ways: in the length of some historical stations dating back to 1958 for the oldest, thus providing more than 65 years of daily data; in the number of countries sampled (16 PICTS) ; and in the variety of coral ecosystems monitored (from atolls to high islands and from barrier reef's external slopes to shallow and narrow lagoons). Measurement devices have evolved over the years to provide increasingly precise and frequent observations so that the ReefTEMPS network was endorsed as a French National Observation Service in 2020, a label ensuring quality controlled and open access data of long-term observations. All stations are publicly available in ASCII or formatted NetCDF files, either on the ReefTEMPS dedicated Information System which also allows quick visualisation of time series, or in the SEANOE marine data platform. All links and accesses to these temperature time series are provided herein. The quality control and longevity of these temperature time series allows diagnosing long-term trends, highlighting the influence of multiple processes on temperature dynamics (e.g., internal waves, cyclones, seasonal and climate modes) and documenting the time evolution of extreme events. All files are made publicly available in dedicated SEANOE repositories (DOI provided herein). [ABSTRACT FROM AUTHOR]

ABSTRACT Warm temperatures accelerate plant growth, but the underlying molecular mechanism is not fully understood. Here, we show that increasing the temperature from 22°C to 28°C rapidly activates proliferation in the apical shoot and root meristems of wild‐type Arabidopsis seedlings. We found that one of the central regulators of cell proliferation, the cell cycle inhibitor RETINOBLASTOMA‐RELATED (RBR), is suppressed by warm temperatures. RBR became hyper‐phosphorylated at a conserved CYCLIN‐DEPENDENT KINASE (CDK) site in young seedlings growing at 28°C, in parallel with the stimulation of the expressions of the regulatory CYCLIN D/A subunits of CDK(s). Interestingly, while under warm temperatures ectopic RBR slowed down the acceleration of cell proliferation, it triggered elongation growth of post‐mitotic cells in the hypocotyl. In agreement, the central regulatory genes of thermomorphogenic response, including PIF4 and PIF7, as well as their downstream auxin biosynthetic YUCCA genes (YUC1‐2 and YUC8‐9) were all up‐regulated in the ectopic RBR expressing line but down‐regulated in a mutant line with reduced RBR level. We suggest that RBR has both canonical and non‐canonical functions under warm temperatures to control proliferative and elongation growth, respectively. [ABSTRACT FROM AUTHOR]

AbstractVarious types of protective coatings, such as ceramics, are used to increase the efficiency of metal parts that are exposed to high heat loads. Maintaining mechanical properties and acceptable thermal stresses requires temperature control for components such as turbine blades, gun barrels or combustion chambers. This paper presents a new method for controlling thermal parameters by solving a non-stationary Cauchy problem for the heat conduction equation. The solution is presented in a cylindrical two-layer area considering the variation of the thermophysical parameters of the metal and ceramic. The non-linear equation was solved by successive approximation method using differential quotients for the space and time variable. In order to regularize the ill-conditioned inverse problem, a quasi-regularization method was applied by performing an energy balance for the ceramic. Numerical calculations were carried out for different thicknesses of the ceramic layer. The temperature, heat flux density and heat transfer coefficient for the protective layer were calculated. For the same values of the heat transfer coefficient for 0.1 and 0.3 mm thick protective layers, the difference in permissible gas temperature differs by 10.5 °C. [ABSTRACT FROM AUTHOR]

This paper investigates a Local Strategy-Driven Multi-Agent Deep Deterministic Policy Gradient (LSD-MADDPG) method for demand-side energy management systems (EMS) in smart communities. LSD-MADDPG modifies the conventional MADDPG framework by limiting data sharing during centralized training to only discretized strategic information. During execution, it relies solely on local information, eliminating post-training data exchange. This approach addresses critical challenges commonly faced by EMS solutions serving dynamic, increasing-scale communities, such as communication delays, single-point failures, scalability, and nonstationary environments. By leveraging and sharing only strategic information among agents, LSD-MADDPG optimizes decision-making while enhancing training efficiency and safeguarding data privacy—a critical concern in the community EMS. The proposed LSD-MADDPG has proven to be capable of reducing energy costs and flattening the community demand curve by coordinating indoor temperature control and electric vehicle charging schedules across multiple buildings. Comparative case studies reveal that LSD-MADDPG excels in both cooperative and competitive settings by ensuring fair alignment between individual buildings' energy management actions and community-wide goals, highlighting its potential for advancing future smart community energy management. [ABSTRACT FROM AUTHOR]

Polymorphic transformation is important in chemical industries, in particular, in those involving explosive molecular crystals. However, due to simulating challenges in the rare event method and collective variables, understanding the transformation mechanism of molecular crystals with a complex structure at the molecular level is poor. In this work, with the constructed order parameters (OPs) and K-means clustering algorithm, the potential of mean force (PMF) along the minimum free-energy path connecting β-HMX and δ-HMX was calculated by the finite temperature string method in the collective variables (SMCV), the free-energy profile and nucleation kinetics were obtained by Markovian milestoning with Voronoi tessellations, and the temperature effect on nucleation was also clarified. The barriers of transformation were affected by the finite-size effects. The configuration with the lower potential barrier in the PMF corresponded to the critical nucleus. The time and free-energy barrier of the polymorphic transformation were reduced as the temperature increased, which was explained by the pre-exponential factor and nucleation rate. Thus, the polymorphic transformation of HMX could be controlled by the temperatures, as is consistent with previous experimental results. Finally, the HMX polymorph dependency of the impact sensitivity was discussed. This work provides an effective way to reveal the polymorphic transformation of the molecular crystal with a cyclic molecular structure, and further to prepare the desired explosive by controlling the transformation temperature. [ABSTRACT FROM AUTHOR]

Simple Summary: Maintaining the optimal temperature in broiler houses, where chickens are raised, is crucial for their health and productivity. However, efficiently managing indoor temperatures is challenging due to the large size of these facilities and varying weather conditions. This study developed and tested a computer model that predicts changes in air temperature inside a broiler house when ventilation systems are adjusted. The model accurately simulated how air movement affects indoor temperatures based on the number of fans operating or stopped. It also accounted for the heat produced by the chickens. The results also showed that adjusting the openings of air inlets can help reduce high temperatures but this can sometimes make the ventilation system less efficient or lead to an uneven temperature distribution. This study confirmed that this approach effectively improves ventilation strategies by comparing the model's predictions with real-life data from broiler houses. This model can assist farmers and engineers in designing better ventilation systems, ensuring better conditions for chickens. Improved conditions will lead to more efficient poultry production, benefiting both the industry and consumers. Maintaining the optimal microclimate in broiler houses is crucial for bird productivity, yet enabling efficient temperature control remains a significant challenge. This study developed and validated a computational fluid dynamics (CFD) model to predict temporal changes in indoor air temperature in response to variable ventilation operations in a commercial broiler house. The model accurately simulated air velocity and airflow distribution for different numbers of tunnel fans in operation, with air-velocity errors ranging from −0.22 to 0.32 m s−1. The predicted airflow rates through inlets and cooling pads showed good agreement with measured values with an accuracy of up to 108.1%. Additionally, the CFD model effectively predicted temperature dynamics, accounting for chicken heat production and ventilation effect. The model successfully predicted the longitudinal temperature gradients and their variations during ventilation cycles, validating its reliability through comparison with experimental data. This study also explored different variable inlet configurations to mitigate the temperature gradient. The variable inlet adjustment showed the potential to relieve the high temperatures but may reduce overall ventilation efficiency or intensify temperature gradients, which confirms the importance of optimising ventilation strategies. This CFD model provides a valuable tool for evaluating and improving ventilation systems and contributes to enhanced indoor microclimates and productivity in poultry houses. [ABSTRACT FROM AUTHOR]

This review article delves into the intriguing phenomenon of low-temperature thermochromism, whereby materials change color in response to temperature variations, with a particular focus on its applications in temperature-sensitive fields like medical storage. By closely examining thermochromic materials, this article highlights their potential to offer innovative solutions for monitoring and preserving thermolabile products that require strict temperature control. This leads to a special emphasis on polydiacetylenes (PDAs), a class of conjugated polymers with unique low-temperature thermochromic properties, positioning them as promising candidates for reliable temperature indicators. This article then explores the underlying mechanisms for fine-tuning the thermochromic behavior of PDAs, particularly discussing recent advancements in PDA design, such as structural alterations of monomers to achieve low-temperature thermochromism. These modifications, influenced by factors like side-chain length, hydrogen-bonding interactions, and the use of copolymers, are intended to result in irreversible color transitions at specific low temperatures, which is crucial to maintaining the integrity of thermally sensitive products. Finally, this article discusses the potential applications of PDAs as thermochromic sensors in tissue biobanking, where their ability to provide visual indications of temperature fluctuations could significantly enhance the monitoring and management of biological samples. [ABSTRACT FROM AUTHOR]

This paper proposes an embedded Internet of Things (IoT) system for bioreactor sensor integration, aimed at optimizing temperature and turbidity control during cell cultivation. Utilizing an ESP32 development board, the system makes advances on previous iterations by incorporating superior analog-to-digital conversion capabilities, dual-core processing, and integrated Wi-Fi and Bluetooth connectivity. The key components include a DS18B20 digital temperature sensor, a TS-300B turbidity sensor, and a Peltier module for temperature regulation. Through real-time monitoring and data transmission to cloud platforms, the system facilitates advanced process control and optimization. The experimental results on yeast cultures demonstrate the system's effectiveness at maintaining optimal growth, highlighting its potential to enhance bioprocessing techniques. The proposed solution underscores the practical applications of the IoT in bioreactor environments, offering insights into the improved efficiency and reliability of culture cultivation processes. [ABSTRACT FROM AUTHOR]

SUMMARY: Photoperiod and temperature‐sensitive male sterility rice is an important line for two‐line hybrid rice, and the changes in the cultivation temperature strictly control its pollen fertility. However, the mechanism by which temperature variation regulates pollen fertility is still unclear. This study obtained stable fertile PA64S(F) and sterile PA64S(S) rice from PA64S by controlling temperature changes. PA64S(F) shows a normal anther development and fertile pollen under low temperature (21°C), and PA64S(S) shows delayed degradation of the tapetum cells, leading to abnormal pollen wall formation and ubisch development under normal temperature (28°C). The accumulation of reactive oxygen species (ROS) positively correlates with the programmed cell death (PCD) process of tapetum cells. The delayed accumulation of ROS in the PA64S(S) tapetum at early stages leads to a delayed initiation of the PCD process. Importantly, we localized ascorbic acid (ASA) accumulation in the tapetum cells and determined that ASA is a major antioxidant for ROS homeostasis. ROS‐inhibited accumulation plants (PA64S‐ASA) demonstrated pollen sterility, higher ASA and lower ROS accumulation in the tapetum, and the absence of PCD processes in the tapetum cell. Abnormal changes in the tapetum of PA64S(S) rice disrupted metabolic pathways such as lipid metabolism, cutin and wax synthesis, sugar accumulation, and phenylpropane, affecting pollen wall formation and substance accumulation, suggesting that the timely accumulation of ROS is critical for male fertility. This study highlights the central role of ROS homeostasis in fertility alteration and also provides an avenue to address the effect of environmental temperature changes on pollen fertility in rice. Significance Statement: This study highlights the central role of ROS homeostasis in fertility alteration also provides an avenue to address the effect of environmental temperature changes on pollen fertility in rice. [ABSTRACT FROM AUTHOR]

This article explores the use of temperature sum models in studying plant spring phenology. These models measure plant development based on temperature-dependent units, such as growing degree hours. The article discusses the limitations of determining the threshold temperature, which represents the lower limit for development, and suggests that it should be estimated for each species. It also examines the implications of using temperature response models as proxies for true physiological responses. The research emphasizes the importance of developing ecophysiological growing degree hour models that consider the unique characteristics of different plant species. Another study focuses on the use of growing degree hour models to predict the timing of spring phenological events in subtropical trees. It finds that using a fixed threshold temperature in these models may lack biological realism, but can still be useful for comparing heat requirements between species or bud types. The authors stress the need for experimental determination of the temperature response and the use of species-specific values in growing degree hour models. [Extracted from the article]

Geophytic plants synchronize growth and quiescence with the external environment to survive and thrive under changing seasons. Together with seasonal growth adaptation, dormancy and sprouting are critical factors determining crop yield and market supply, as various geophytes also serve as major food, floriculture, and ornamental crops. Dormancy in such crops determines crop availability in the market, as most of them are consumed during the dormant stage. On the other hand, uniform/maximal sprouting is crucial for maximum yield. Thus, dormancy and sprouting regulation have great economic importance. Dormancy–sprouting cycles in geophytes are regulated by genetic, exogenous (environmental), and endogenous (genetic, metabolic, hormonal, etc.) factors. Comparatively, the temperature is more dominant in regulating dormancy and sprouting in geophytes, unlike above-ground tissues, where both photoperiod and temperature control are involved. Despite huge economic importance, studies concerning the regulation of dormancy and sprouting are scarce in the majority of geophytes. To date, only a few molecular factors involved in the process have been suggested. Recently, omics studies on molecular and metabolic factors involved in dormancy and growth regulation of underground vegetative tissues have provided more insight into the mechanism. Here, we discuss current knowledge of the environmental and molecular regulation and control of dormancy and sprouting in geophytes, and discuss challenges/questions that need to be addressed in the future for crop improvement. [ABSTRACT FROM AUTHOR]

We describe a low-cost method for the synthesis of reversible thermochromic K 2 O·nSiO 2 -based anti-fire materials with bidirectional responsion and memory function, which was significant for energy-saving and fire-resistant applications. Here, the reversible thermochromic (RTC) and inverted reversible thermochromic (IRTC) K 2 O·nSiO 2 -based anti-fire glass were prepared via an in-situ reaction using a high solid content and low viscosity SiO 2 sol (HSLV SiO 2 sol, 55 wt%). The morphological, thermochromic, thermal insulation, and memory performances were systematically characterized. The pincer-like structure, rod-like structure and the layered microporous morphology were clearly shown in scanning electron microscopy (SEM) micrographs. The color change, foaming, and memory mechanisms were further investigated in detail. The significant differences appeared in the visible region of RTC and IRTC K 2 O·nSiO 2 -based anti-fire glass during heating and cooling process. FTIR spectra were used to characterize the difference among RTC, IRTC and control samples. The results indicated that a small amount of NH 4 + caused the K 2 O·nSiO 2 -based anti-fire glass to exhibit IRTC characteristics, and the continuous addition of polyhydric alcohols was the key to obtain RTC performance. The IRTC K 2 O·nSiO 2 -based anti-fire glass was suitable for the conservatories or greenhouses, and the RTC K 2 O·nSiO 2 -based anti-fire glass reduced the direct sunlight exposure to control the indoor temperature. Combined with morphological and Tg analysis, the thermal insulation performance was enhanced by a microporous insulating layer with a sponge-like structure. We also used the bidirectional reversible thermochromic performance to prepare a novel anti-fire glass component for construction with anti-counterfeiting function. This work provided a new approach for the application of multifunctional smart windows. [ABSTRACT FROM AUTHOR]