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To develop new luminescent materials for optical thermometers, a series of Er3+/Eu3+doped double perovskite La2MgSnO6 phosphors are synthesized by a high-temperature solid-phase method. The structure, luminescence performance, energy transfer, and thermal sensitivity are systematically studied by X-ray diffraction (XRD), scanning electron microscopy fluorescence spectroscopy, lifetime decay curve, and temperature-dependent emission spectra. The prepared samples possess good coincidence with pure perovskite phase, and the refined high-quality XRD data reveal that Eu3+ and Er3+jointly occupy La3+ sites. which is attributed to the effective energy transfer from Er3+ to Eu3+ ions. By adjusting the doping concentration of Eu3+, the emission of Er3+ is attenuated and the luminous color is modulated from green to orange-red. These demonstrate the existence of energy transfer between Er3+ and Eu3+. In addition, the optimized La2MgSnO6: 0.075Er3+, 0.04Eu3+ phosphor exhibits excellent thermal stability and good temperature cycling. The emission intensity showed good cycling in the process of repeated heating and cooling, and maintained to 76% of the initial temperature (303K) at 403K. Studied the optical temperature sensing performance of LMS: 0.075Er3+, 0.04Eu3+ fluorescent powder. The results of fitting the fluorescence intensity ratio with the non-thermal coupling characteristic peaks of 555 and 706nm showed excellent optical sensitivity, and the Sa and Sr were calculated as 0.0029K−1 and 1.21%K−1, respectively. All results indicate that LMS: 0.075Er3+, 0.04Eu3+ phosphors could have potential applications for non-contact optical temperature measurement materials. [ABSTRACT FROM AUTHOR]

Highlights This paper investigated the effect of elevated temperature on the impact‐induced deformation and damage behavior of 3D angle‐interlock woven composites. The transverse impacts were carried out at high temperatures of 90°C and 130°C using Split Hopkinson Pressure Bar matched with controlled environmental device. A meso‐scale finite element model considering the thermal‐mechanical coupling has been developed, and the numerical results were compared with the experimental data and high‐speed photography to study the effect of temperature and reinforcement architecture on the dynamic behaviors of the composites. The damage mechanisms at elevated temperatures were studied. Results show that the impact resistance of the 3D angle‐interlock woven composites degraded at the glassy region of the epoxy resin, then enhanced at the glass transition temperature (Tg), this phenomenon became more pronounced in the warp direction. Such behavior should be ascribed to the improved toughness and ductility of the resin matrix. The local plastic deformation of resin before damage slowed down matrix cracking and composites failure. Further, the reinforcement play a key role in the adiabatic heating and plastic deformation of the composites at high temperature. The impact test of 3D woven composites was conducted at elevated temperatures. The high temperature significantly affects the dynamic properties of composites. The increased toughness and plasticization of resin diminished impact damage. A mesoscale thermo‐mechanical coupled finite element model was developed. The reinforcement plays a key role in the damage process and adiabatic heating. [ABSTRACT FROM AUTHOR]

Application of radio frequency (RF) treatment has been studied for disinfesting agricultural products, and RF heating non-uniformity has been demonstrated to directly influence pest mortality in treated products. The purpose of this study was to investigate the combined effects of holding time after conveyor movement, layer rearrangement, and sample mixing on the mortality of Rhyzopertha dominica (R. dominica) in milled rice treated with hot air-assisted RF heating. Results showed that hot-air assistance during the process of RF heating can lead to a rapid temperature rise and improve the temperature distribution. RF heating followed by holding samples in hot air for specific time periods effectively improved the heating uniformity of samples and raised the mortality of R. dominica in milled rice. Compared with the stationary conditions, conveyor movement, layer rearrangement, and sample mixing improved the hot air-assisted RF heating uniformity of the sample, raised pest mortality and reduced the thermal holding time after RF treatment required to achieve 100% pest mortality in milled rice. The findings of this study provide a valuable proof of concept for improving RF heating uniformity and optimizing parameters in RF disinfestation protocols for milled rice. [ABSTRACT FROM AUTHOR]

Exotic topological domains in BiFeO3 nanoislands have attracted much attention regarding their potential applications in advanced electronic devices. Here, different from the earlier reported disordered distributed BiFeO3 nanoislands formed by a self-assembly method, we fabricated an ordered BiFeO3 nanoisland array by mask-assisted pulsed laser deposition on a SrTiO3 substrate, which exhibits a center-converged in-plane polarization component and a monodomain pattern along the vertical direction. Such center-type quad-domain structures exhibit high stability, maintaining their topological structures after heating to 250 °C and subsequently cooling to room temperature. Moreover, they can be switched by applying a scanning electric field and recovered by applying a heating and cooling process. Observing this topological structure in BiFeO3 nanoislands might provide a suitable platform for further exploration of its topological phase transition properties, new functions, and potential applications. [ABSTRACT FROM AUTHOR]

Decarbonizing fossil-fuel usage is crucial in mitigating the impacts of climate change. The burning of fossil fuels in boilers during industrial process heating is one of the major sources of CO2 in the industry. Electrification is a promising solution for decarbonizing these boilers, as it enables renewable energy sources to generate electricity, which can then be used to power the electric boilers. This research develops a user-driven simulation model with realistic data and potential temperature data for a location to estimate boilers' current energy and fuel usage and determine the equivalent electrical boiler capacity and energy usage. A simulation model is developed using the Visual Basic Application (VBA)® and takes factors such as current boiler capacity, steam temperature and pressure, condensate, makeup water, blowdown, surface area, and flue gas information as input. Random numbers generate the hourly temperature variation for a year for discrete-event Monte Carlo Simulation. The simulation generates the hourly firing factor, energy usage, fuel usage, and CO2 emissions of boilers for a whole year, and the result compares fossil-fuel and electrical boilers. The simulated data are validated using real system data, and sensitivity analysis of the model is performed by varying the input data. [ABSTRACT FROM AUTHOR]

The process integration and electrification concept has significant potential to support the industrial transition to low- and net-zero-carbon process heating. This increasingly essential concept requires an expanded set of process analysis tools to fully comprehend the interplay of heat recovery and process electrification (e.g., heat pumping). In this paper, new Exergy Pinch Analysis tools and methods are proposed that can set lower bound work targets by acutely balancing process heat recovery and heat pumping. As part of the analysis, net energy and exergy load curves enable visualization of energy and exergy surpluses and deficits. As extensions to the grand composite curve in conventional Pinch Analysis, these curves enable examination of different pocket-cutting strategies, revealing their distinct impacts on heat, exergy, and work targets. Demonstrated via case studies on a spray dryer and an evaporator, the exergy analysis targets net shaft-work correctly. In the evaporator case study, the analysis points to the heat recovery pockets playing an essential role in reducing the work target by 25.7%. The findings offer substantial potential for improved industrial energy management, providing a robust framework for engineers to enhance industrial process and energy sustainability. [ABSTRACT FROM AUTHOR]

Self‐resistance electric (SRE) heating for the curing of carbon fiber reinforced plastic (CFRP) offers the benefits of saving energy consumption and reducing investment in equipment. In this work, the investigation was carried out to illustrate the effect of carbon nanotubes (CNTs) addition (0.5, 1.0, and 1.5 wt%) on the thermoset curing and mechanical properties of carbon fiber‐reinforced epoxy laminates fabricated by SRE heating method. The results show that adding CNTs can improve the temperature uniformity and interlayer‐resin flow during the SRE heating process and have a limited influence on the curing degree of CFRP composites. The tensile strength in the longitudinal direction of the composites increased with the increase of CNT addition. Meanwhile, the flexural strength and interlaminar shear strength had the maximum value with the CNTs content of 0.5 wt% and decreased significantly at the CNTs content of 1.5 wt%. It concludes that the appropriate content of CNTs addition has the potential to improve the thermoset curing performance and mechanical properties of the CFRP laminate composites fabricated by SRE heating. Highlights: This study focuses on the effect of CNT addition on SRE heating for CFRP.The addition of CNTs improved the temperature uniformity during SRE heating.The addition of CNTs can reduce the voids of SRE‐cured CFRP composites.Threshold value of CNTs affected the mechanical performance of SRE‐cured CFRP. [ABSTRACT FROM AUTHOR]

Mathematical modeling of multiphysics processes of Joule heating has been conducted using a finite element model of a stationary current-supplying mould (CSM). To manufacture bimetallic products using a stationary current-supplying mould with a circular cross-section during melting of a discrete additive at its batch feeding, the study presents the results of calculated assessment of the dependence of such metal pool shape parameters as the mirror diameter and the liquid fraction depth on the slag pool depth and CSM design parameters, namely the mould diameter, the thickness of copper bushings in the mould current-supplying and forming sections, the water-cooled bottom plate thickness, and the variations in the graphite lining height caused by wear. The findings will contribute to improvement of the mould design, optimization of the metal pool shape, and the technology of discrete additive melting at batch feeding in a stationary CSM. [ABSTRACT FROM AUTHOR]

The densification and sintering of ceramics using microwaves is first reported in the mid‐1960s. Today, the reduced carbon footprint of this process has renewed interest as it uses less energy overall compared to conventional process heating/furnaces. However, scaling up and commercializing the microwave sintering process of ceramics remains a formidable challenge. As a contactless method, microwave sintering offers geometric flexibility over other field‐assisted sintering processes. Yet, the inability to address multiscale, multiphysics‐driven heterogeneities arising during microwave coupling limits discussions about a future scale‐up process. Herein, the case is made that unlike 60 years ago, new advances in multiscale computational modeling, materials characterization, control systems, and software open up new avenues for addressing these challenges. More importantly, the rise of additive manufacturing techniques demands the innovation of sintering processes in the ceramics community for realizing near‐net‐shaped and complex parts for applications ranging from medical implants to automotive and aerospace parts. [ABSTRACT FROM AUTHOR]

Additive manufacturing is gaining interest for printing of noble metals. In this study, aerosol jet printing was applied to fabricate traces from commercial silver nanoparticle ink. A self-built three dimensional printing machine was used without or with in-line substrate heating. A conductive traces were printed on flexible polyimide substrates. Subsequently, sintering was conducted by furnace or near-infrared source. Examination of the sample using scanning electron and atomic force microscopy revealed the existence of both micro- and nanoscale pores in the structure. Local open porosity, aerosol extensive spatter and wide porous overspray were key defects found in samples printed without substrate heating. All the features affect the properties and reliability of silver prints. In-line process heating increased the concentration of nanoparticles and limited defects formation. What is more, the width of traces decreased from 31 µm to 19 µm with simultaneous thickness increase from 1.2 to 5.5 µm due to substrate heating. The final structure was influenced by sintering method and its time. Elongated time of sintering decreased porosity and roughness of the printed traces. Nevertheless, IR sintering provided the smoothest sample surface with lowest Sa roughness of 16 nm, and significantly improved bonding of aggregates. What is more, the printed structure had a measured sheet resistance of 8.3×10−2 Ω/□. [ABSTRACT FROM AUTHOR]

Microflares are energetically smaller versions of solar flares, demonstrating the same processes of plasma heating and particle acceleration. However, it remains unclear down to what energy scales this impulsive energy release continues, which has implications for how the solar atmosphere is heated. The heating and particle acceleration in microflares can be studied through their X-ray emission, finding predominantly thermal emission at lower energies; however, at higher energies it can be difficult to distinguish whether the emission is due to hotter plasma and/or accelerated electrons. We present the first application of nested sampling to solar flare X-ray spectra, an approach that provides a quantitative degree of confidence for one model over another. We analyse Nuclear Spectroscopic Telescope Array X-ray observations of a small active region microflare (A0.02 GOES/XRS class equivalent) that occurred on 2021 November 17, with a new python package for spectral fitting, sunkit-spex , to compute the parameter posterior distributions and the evidence of different models representing the higher energy emission as due to thermal or non-thermal sources. Calculating the Bayes factor, we show that there is significantly stronger evidence for the higher energy microflare emission to be produced by non-thermal emission from flare-accelerated electrons than by an additional hot thermal source. Qualitative confirmation of this non-thermal source is provided by the lack of hotter (10 MK) emission in Solar Dynamic Observatory's Atmospheric Imaging Assembly's extreme ultraviolet data. The nested sampling approach used in this paper has provided clear support for non-thermal emission at the level of 3 × 1024 erg s−1 in this tiny microflare. [ABSTRACT FROM AUTHOR]

The article presents the results of experimental studies on the gasification of mixtures of brown coal and polyethylene (up to 20 wt% fraction) in a laboratory reactor. The work aims to study the agglomeration process during the heating and oxidation of the mixtures. The measurement results (gas composition, pressure drop) provide indirect information on the dynamics of thermal decomposition and structural changes in the fuel bed. We have shown that the interaction between polyethylene and a coal surface leads to the formation of dense agglomerates, in which the molten polymer acts as a binder. Clinkers form as a result of interfacial interactions between components and filtration flow rearranging. The hydrogen/carbon ratio in the solid residue of coal-polyethylene co-gasification increases from 0.07–0.2 to 1.11, indicating the formation of stable hydrocarbon compounds on the carbon surface. The conducted research makes it possible to identify possible interactions between chemical reactions and transfer processes that lead to agglomeration in mixtures of coal with polyethylene. [ABSTRACT FROM AUTHOR]

In this study, the object of the research is low-rank coal during the process of thermal heating of five types: brown, high moisture brown, long-flame, coke weakly sintering and coke fusinite. In the research, when conducting thermal and gas analysis in inert media, the problem of using low-rank coal in the thermal heating process to obtain volatile fuel gases was solved by identifying the quantitative and qualitative performance of its behavior. Quantitative indicators are determined as the mass of thermal destruction products: the mass of coal tar and gas products and semi-coke under optimal temperature conditions of their maximum release. Qualitative indicators of coal behavior are components of thermal decomposition products. It is revealed that the behavior of low-rank coals in the process of thermal heating is determined by the degree of metamorphism. In this case, long-flame and brown coals have a lower release of volatile fuel gases than coke weakly sintering and coke fusinite coals due to a lower degree of metamorphism and greater degrees of thermal oxidation and dehydration. Thermal decomposition component ranges consisting of polyaromatic fragments (HCN, C6H12, C4H5N), greenhouse gases (CH4 and CO2), toxic gases (H2S and NH3) and synthesis gases (CO and H2) have the highest share of release. Optimal temperature conditions and ranges for the release of low molecular weight gases used as high calorific volatile fuel gases are obtained. The results can be used in the design, optimization and construction of thermal heating equipment, correction of gasification and pyrolysis processes. Moreover, they can be applied in localized coal tar spots minimization technologies and for designing targeted gases extraction [ABSTRACT FROM AUTHOR]

Thermal energy in the industrial sector for process heating applications in the range of 50 to 250°C consumes about 35% of the global fossil fuel. Cascaded solar thermal systems are promising solutions to meet clean and uninterrupted thermal energy supply for industrial process heating. Well-engineered cascaded arrangement of solar thermal collector (STC) and photovoltaic thermal (PVT) collector can attain an average solar fraction of more than 50%. In the present research, a solar-assisted process heating system, wherein a STC integrated in series with PVT, has been designed to produce low- to medium-temperature heat at higher solar fractions. Herein, thermal performance and economic viability of this novel system have been investigated and analyzed methodically. In the present research, a comprehensive TRNSYS simulation model is developed and validated experimentally. Results show that PVT integrated with heat pipe evacuated tube collector (PVT-HPETC) and PVT integrated with flat plate collector (PVT-FPC) system can generate thermal energy as high as 1625 and 1420 W with a thermal efficiency of 81 and 77% and exergy efficiency of 13.22 and 12.72%. Levelized cost of heat (LCOH) for PVT-HPETC at process heat temperatures of 60, 70, and 80°C is 0.214, 0.208, and 0.201 MYR/kWh, respectively. It is worth to note that LCOH is less than the existing cost of heat generation which proves that these systems are economically feasible. [ABSTRACT FROM AUTHOR]

With the development of distributed power sources in the distribution network, the algorithm of distribution network reconfiguration is gaining attention from experts and scholars. Its goal is to reduce the power loss during power transmission, so as to reduce the power grid loss during power transmission. And weaken the electric heating effect in the process of electric energy transmission, thus maintaining the safety of the surrounding residents. Due to the wire impedance effect, a lot of electric energy of the circuit is lost to electric heating, which is easy to cause local overheating and lead to fire. This will not only cause power loss, but also endanger the safety of surrounding residents. To address the issue, experiments on distribution grid reconstruction are performed using the enhanced particle swarm-fish swarm algorithm with the Elecgrid self-constructed dataset. Initially, low-voltage distributed power sources in parallel are connected to the circuit, thereby decreasing internal resistance and electrical heat. Then, by controlling the circuit in the system, the double separation relay adjusts the inductance and capacitance of the conductor, thus reducing the reactance length. Additionally, particle swarm particles are mutated to enable them to jump out of the local optimum, and elite fish approach is used to expand the search area. Finally, the proposed fusion algorithm is applied to the self-built data set of Elecgrid and compared with the other three algorithms. The fusion algorithm serves as the standard test system for this comparison. The active power loss of the hybrid algorithm is 63 kW at an operating voltage of 0.74 V. The loss work of the other three algorithms is 74 kW, 97 kW and 109 kW respectively. The mixed algorithm has the lowest loss among the four algorithms. The experiments are repeated for six times, and the linear fitting degrees of the four algorithms are 0.9804, 0.9527, 0.9612 and 0.9503, respectively. The experimental results show that the application of this algorithm can effectively reduce the active loss in the process of distribution network reconfiguration, thus reducing energy consumption; At the same time, it can reduce the electric heating in the process of electric energy transmission, and then prevent the occurrence of fire. There are three main contributions of this study. Firstly, the resistance in the transmission path is reduced by using this algorithm, so that the power transmission efficiency can be analyzed more accurately. Secondly, the new algorithm enriches the power safety maintenance method; Finally, the fire caused by local overheating of the line is reduced by fusion algorithm. [ABSTRACT FROM AUTHOR]

Solar energy demand is growing for future energy needs in different sectors to replace fossil fuels, which leads to a reduced carbon footprint and global warming. Evacuated tube solar collectors (ETSC) harness solar thermal energy for air heating, water heating, and drying in domestic and industrial sectors. The review paper comprises ETSC technology categorization, influencing factors like fin arrangement, integration of phase change material, tilt angle, solar radiation, and airflow rate on the performance of ETSC-based solar air heaters and dryers. The thermal performance parameters, like the collector efficiency, dryer efficiency, energy and exergy efficiency, thermal profile, zone temperature, relative humidity, heat loss during operations, etc., are reviewed. The developed ETSC-based air heating systems and solar dryers for drying agricultural products are performed effectively. However, research progress on improving the thermal performance integrated with nanofluids and phase change materials was discussed. CO2 mitigation analysis and global standards for ETSC-based air heaters and dryers are compiled. A large scope exists by use of solar air heaters (SAH) for food commodity drying with a suitable drying chamber and improving the designs of ETSC-based solar dryers. The work accomplished by various researchers has been analyzed in this study for prospective research gaps in the context of future design and development. [ABSTRACT FROM AUTHOR]

Microwave-induced thermoacoustic imaging (MTI) has the advantages of high resolution, high contrast, non-ionization, and non-invasive. Recently, MTI was used in the field of breast cancer screening. In this paper, based on the finite element method (FEM) and COMSOL Multiphysics software, a three-dimensional breast cancer model suitable for exploring the MTI process is proposed to investigate the influence of Young's modulus (YM) of breast cancer tissue on MTI. It is found that the process of electromagnetic heating and initial pressure generation of the entire breast tissue is earlier in time than the thermal expansion process. Besides, compared with normal breast tissue, tumor tissue has a greater temperature rise, displacement, and pressure rise. In particular, YM of the tumor is related to the speed of thermal expansion. In particular, the larger the YM of the tumor is, the higher the heating and contraction frequency is, and the greater the maximum pressure is. Different Young's moduli correspond to different thermoacoustic signal spectra. In MTI, this study can be used to judge different degrees of breast cancer based on elastic imaging. In addition, this study is helpful in exploring the possibility of microwave-induced thermoacoustic elastic imaging (MTAE). [ABSTRACT FROM AUTHOR]

The thermal processes of recrystallization in porous copper compacts heated after cold pressing in a steel die were experimentally studied. The recrystallization stages, with temperatures corresponding to data determined with metallographic and other research methods, were identified. Only the first tempering stage was found to occur uniformly throughout the entire volume at a heating temperature of 190°C. Upon further heating, a linear stage ensued, where the temperature remained consistent throughout the entire volume of the material, persisting until the next stage. This was accompanied with energy release, as confirmed by a zero temperature gradient across all regions within the sample. With an increase in temperature to 210–215°C, a thermal surge was observed and visible temperature asynchronization was noted in individual volumes of the sample. However, this was followed by a temperature gradient between individual volumes. At this stage, asynchronized thermal behavior within the sample was observed for the first time, as evidenced by the emergence of thermal waves. Subsequent stages demonstrated nonlinear thermal behavior, evidenced by several competing processes leading to the wave-like transfer of energy accumulated as the copper powders deformed during cold pressing. Like recrystallization processes with first-order reactions in the high-temperature synthesis of intermetallic and other compounds, the emergence of thermal waves was due to several competing processes. Thus, if microplastic deformation processes occurred during recrystallization, then traveling waves could arise in the system, which was actually revealed. This could lead to thermal interference and subsequently to local buildup of thermal energy, potentially causing a sharp increase in temperature in individual areas of the wires deformed during switching and, as a result, their ignition. The temperature surges observed were likely to cause the combustion of insulating materials. Therefore, this can explain the causes of accidents that occur in the operation of complex mechanisms with numerous electrical circuits. [ABSTRACT FROM AUTHOR]

In this research work, an attempt has been made to address the heat and power integration opportunities for the process of the chlorination of benzene. This process produces a mixture of chlorobenzenes. To increase the production of the dichlorobenzene portion, the ratio of chlorine to benzene is typically 2:1. A process simulation model is designed using Aspen Plus for the production of 70,000 tons/year of dichlorobenzene via the reaction of liquid benzene with gaseous chlorine. Energy analysis is performed for the effective utilization of the utilities by networking the heat exchangers. This modification reduced the process heating and cooling requirements by 56.7% and 12.7%, respectively, and a reduction by 35.4% in the operating costs is achieved, while the annualized fixed cost increased by 9.6%; these changes resulted in savings in the total annual costs of about 10.9%. [ABSTRACT FROM AUTHOR]

Atmospheric escape is crucial to understanding the evolution of planets in and out of the solar system and to interpreting atmospheric observations. While hydrodynamic escape simulations have been actively developed incorporating detailed processes such as UV heating, chemical reactions, and radiative cooling, the radiative cooling by molecules has been treated as emission from selected lines or rotational/vibrational bands to reduce its numerical cost. However, ad hoc selections of radiative lines would risk estimating inaccurate cooling rates because important lines or wavelengths for atmospheric cooling depend on emitting conditions such as temperature and optical thickness. In this study, we apply the correlated-k distribution (CKD) method to cooling rate calculations for H2-dominant transonic atmospheres containing H2O or CO as radiative species, to investigate its numerical performance and the importance of considering all lines of the molecules. Our simulations demonstrate that the sum of weak lines, which provides only 1% of the line emission energy in total at optically thin conditions, can become the primary source of radiative cooling in optically thick regions, especially for H2O-containing atmospheres. Also, in our hydrodynamic simulations, the CKD method with a wavelength resolution of 1000 is found to be effective, allowing the calculation of escape rate and temperature profiles with acceptable numerical cost. Our results show the importance of treating all radiative lines and the usefulness of the CKD method in hydrodynamic escape simulations. It is particularly practical for heavy-element-enriched atmospheres considered in small exoplanets, including super-Earths, without any prior selections for effective lines. [ABSTRACT FROM AUTHOR]

Atmospheric escape in exoplanets has traditionally been observed using hydrogen Lyman-α and Hα transmission spectroscopy, but more recent detections have utilized the metastable helium triplet at 1083 nm. Since this feature is accessible from the ground, it offers new possibilities for studying atmospheric escape. Our goal is to understand how the observability of escaping helium evolves during the lifetime of a highly irradiated gas giant. We extend our previous work on 1D self-consistent hydrodynamic escape from hydrogen-only atmospheres as a function of planetary evolution to the first evolution-focused study of escaping hydrogen–helium atmospheres. Additionally, using these novel models we perform helium triplet transmission spectroscopy. We adapt our previous hydrodynamic escape model to now account for both hydrogen and helium heating and cooling processes and simultaneously solve for the population of helium in the triplet state. To account for the planetary evolution, we utilize evolving predictions of planetary radii for a close-in 0.3  M Jup gas giant and its received stellar flux in X-ray, hard and soft extreme-ultraviolet (UV), and mid-UV wavelength bins assuming a K-dwarf stellar host. We find that the helium triplet signature diminishes with evolution. Our models suggest that young (≲ 150 Myr), close-in gas giants (∼1 to 2  R Jup) should produce helium 1083 nm transit absorptions of |$\sim 4~{{\ \rm per\ cent}}$| or |$\sim 7~{{\ \rm per\ cent}}$|⁠ , for a slow- or fast-rotating K dwarf, respectively, assuming a 2  per cent helium abundance. [ABSTRACT FROM AUTHOR]

Due to the limitation by the coking temperature of furfural, the bottom temperature of the stripping tower of the furfural refining unit is difficult to further increase after the extract oil recovery system undergoes three-effect evaporation. When processing high aromatic hydrocarbon feedstocks, due to the high content of aromatics and good solubility of solvents and aromatics, the extract oil of the product has a high solvent content. The method of secondary heating the extract liquid can increase the bottom temperature of the extract oil stripping tower, and has a good effect on reducing the solvent content of the extract oil. Through simulation calculation, it was found that the optimal location for the extract liquid secondary heater is between the three-effect evaporation tower and the flash tower, which can reduce the solvent content of the extract oil by 83.1% compared to no secondary heating. The optimal amount of steam used in the stripping tower is 5% of the oil extract from the bottom of the tower. The temperature at the top of the stripping tower is approximately inversely proportional to the solvent content of the extract oil at the bottom of the stripping tower, and the attention should be paid to the influence of oil carried in the overhead gas. For units with low load operation or designed processing capacity, setting up an extract oil circulation process can increase the bottom temperature of the stripper, which is beneficial for reducing the solvent content at the bottom of the stripper. By setting the secondary heating and circulation process of the extract oil, optimizing the operating pressure, top temperature, and steam volume of the stripping tower, the solvent content of the extract oil can be controlled to be less than 150 µg/g, reducing the solvent consumption of the unit. [ABSTRACT FROM AUTHOR]

Ohmic heating may improve bioactive compounds and processing, ensuring food safety of beverages, liquid and pasty food, or liquid with solid pieces. Due to those traits, this study conducted a comparison between ohmic heating technology and conventional heating (CH), with a focus on assessing the impact of both methods on functional compounds (such as angiotensin-converting enzyme inhibition, α-amylase and α-glucosidase inhibition, and antioxidant activity) in both fresh and thawed raw sheep milk, which had been frozen for up to 3 mo. Different ohmic heating conditions were applied and compared to CH (3.33–8.33 V/cm vs. CH [73°C/15 s]). A total of 18 peptides with some functional activities were identified by MALDI-TOF mass spectrometry analysis. Ohmic heating samples presented the highest activities related to health, followed by CH and raw milk samples; antioxidant activity range was from 0.11% to 0.71%, antihypertensive activity ranged from 0.20% to 0.72%, and antidiabetic activity ranged from 0.21% to 0.79%. Of 51 volatile compounds detected, some were degraded by freezing, storing, and heating the sheep milk. This study showed for the first time that ohmic heating processing improved sheep milk bioactive peptides and preserved volatile compounds. [Display omitted] [ABSTRACT FROM AUTHOR]

A transient extreme rainstorm that occurred over Guangzhou city, China, on 22 May 2020, has been investigated based on two ensemble prediction systems (EPSs), one with 9‐km (TRAMS9km‐EPS) and the other with 3‐km (TRAMS3km‐EPS) grid spacings, respectively. The results show that the better performance in the rainstorm event of TRAMS3km‐EPS than that of TRAMS9km‐EPS has been attributed to the reasonable simulation of an eastward propagating meso‐β‐scale convective vortex (MβCV). The composite evolution of the good‐performing members for the two EPSs has verified the important role of the MβCV in modulating the structure of low‐level jet (LLJ) to converge toward the Guangzhou city, facilitating the formation of the rainstorm. In comparison to the gravity wave disturbance when LLJ passed through the mountains in TRAMS3km‐EPS, the topographic effect induced the moist air to ascend deeply in TRAMS9km‐EPS, which directly led to earlier outbreaks of convection and rainstorm processes and affected the structural intensity of the upstream MβCV. Quantitative PV diagnosis has demonstrated that the dispersedly strong high‐PV systems in TRAMS3km‐EPS were caused by positive feedback effect between meso‐scale convective systems and diabatic heating, and were favorable for the entire cyclonic development of MβCV. The unsymmetrical PV tendency around the moving MβCV under the combined effect of diabatic heating and advection process in TRAMS9km‐EPS resulted in a rapid propagation of this system. However, the symmetrically developed PV system within the MβCV in TRAMS3km‐EPS allowed the enhanced cyclonic circulation to persistently affect Guangzhou city, inducing extreme rainstorms similar to the observations. Plain Language Summary: An eastward propagating meso‐β‐scale convective vortex (MβCV) that triggered a transient extreme rainstorm over Guangzhou city, China, on 22 May 2020, has been examined and simulated using a same ensemble prediction system (EPS) model with two horizontal resolutions (3 and 9 km). In this study, we have analyzed the similarities and differences between the two EPSs. Our results show that the effect of horizontal resolution resulted in distinct MβCV structures in the two EPSs and led to different rainstorm processes in terms of intensity and duration. Some aspects, such as the low‐level jet, topographic effect, and small‐scale disturbances, are specifically compared between the two EPSs. The associated research highlights the effect of horizontal resolution on the MβCV simulation and a possible development mechanism of such a mesoscale system. Key Points: The topographic uplift and fore‐mountain convergence processes are amplified in low‐resolution ensemble simulationsThe unsymmetrical PV tendency around MβCV center determines the direction and velocity of the moving MβCVSmall‐scale convective systems enhance cyclonic structure of MβCV through positive feedback with diabatic heating [ABSTRACT FROM AUTHOR]

In this article, we address the application of phase field crystal (PFC) theory, a hybrid atomistic-continuum approach, for modeling nanostructure kinetics encountered in laser deposition. We first provide an overview of the PFC methodology, highlighting recent advances to incorporate phononic and heat transport mechanisms. To simulate laser heating, energy is deposited onto a number of polycrystalline, two-dimensional samples through the application of initial stochastic fluctuations. We first demonstrate the ability of the model to simulate plasticity and recrystallization events that follow laser heating in the isothermal limit. Importantly, we also show that sufficient kinetic energy can cause voiding, which serves to suppress shock propagation. We subsequently employ a newly developed thermo-density PFC theory, coined thermal field crystal (TFC), to investigate laser heating of polycrystalline samples under non-isothermal conditions. We observe that the latent heat of transition associated with ordering can lead to long lasting metastable structures and defects, with a healing rate linked to the thermal diffusion. Finally, we illustrate that the lattice temperature simulated by the TFC model is in qualitative agreement with predictions of conventional electron–phonon two-temperature models. We expect that our new TFC formalism can be useful for predicting transient structures that result from rapid laser heating and re-solidification processes. [ABSTRACT FROM AUTHOR]

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The purpose of the study was to determine the influence of the main following factors on the efficiency of the process of high-temperature refining of natural and artificial graphite: processing temperature, distribution of metal oxides, and changes in the aggregate state of ash impurities. Thermal processing of natural graphite from Ukrainian deposits and anthracite from Donetsk coal basin was carried out in a chamber furnace at a holding time of 10-20 minutes in a temperature range of 1500-3000°C. The quality of refining was carried out by ICP-OES and XRF analysis methods. It was established that the refining process may be divided into three following periods: 0-1600°C (removal of moisture, volatiles, and decomposition of carbonates); 1600-2600°C (evaporation of main ash-forming metals Fe, Si, Al, Ca, Mg in the form of oxides, silicides, and carbides); and 2600-3000°C (evaporation of refractory compounds Ti, V, Mo, the content of which in the initial raw material determines the processing temperature and the quality of the final product). The distribution of metal oxides in the initial carbon material is not uniform, which complicates the use of equilibrium state models. The transition of ash into the liquid and then gaseous state has a significant impact on the result of heat treatment. This is what determines the choice of the process scheme. Intermittent process is the heating by an external heater in an inert gas environment. Continuous process is the heating of the material in moving containers or processing in an electrothermal fluidized bed. [ABSTRACT FROM AUTHOR]

As is well known, the metal annealing process has the characteristics of heat concentration and rapid heating. Traditional vacuum annealing furnaces use PID control method, which has problems such as high temperature fluctuation, large overshoot, and long response time during the heating and heating process. Based on this situation, some domestic scholars have adopted fuzzy PID control algorithm in the temperature control of vacuum annealing furnaces. Due to the fact that fuzzy rules are formulated through a large amount of on-site temperature data and experience summary, there is a certain degree of subjectivity, which cannot ensure that each rule is optimal. In response to this drawback, the author combined the technical parameters of vacuum annealing furnace equipment, The fuzzy PID temperature control of the vacuum annealing furnace is optimized using genetic algorithm. Through simulation and comparative analysis, it is concluded that the design of the fuzzy PID vacuum annealing furnace temperature control system based on GA optimization is superior to fuzzy PID and traditional PID control in terms of temperature accuracy, rise time, and overshoot control. Finally, it was verified through offline experiments that the fuzzy PID temperature control system based on GA optimization meets the annealing temperature requirements of metal workpieces and can be applied to the temperature control system of vacuum annealing furnaces. [ABSTRACT FROM AUTHOR]

The VLF-induced ionospheric heating events from the powerful transmitter NWC are collected at extremely low solar activity years of 2008–2009, and their spatial and temporal distribution features are investigated. The spatial distribution of heating signals exhibits clear north-direction inclination of 2–3°, and covering area within 300 km radius in longitude and latitude. Plasma parameters show the obvious negative correlations between decreasing Ne and increasing Te, and positive correlations of the increasing ion density and ion temperature during the VLF heating time. The ions move upwards to cause the perturbations in ULF electric field due to V ⇀ × B ⇀ . The VLF heating events easily occur at seasons with low plasma density, which illustrates that low plasma environment plays an important role in VLF-induced ionospheric heating. Typical three enhanced VLF signals are obtained, one at 19.8 kHz with the largest amplitude, one at the broadened frequency band of 19.8 ± 300 Hz with one order of amplitude decreasing, and one between 19.5 kHz and lower hybrid frequency with at least two orders of amplitude reductions relative to that at 19.8 kHz but still one order increasing relative to non-heating region. These quasi electrostatic waves during VLF heating may not be from the VLF whistler conversion, but the lightning-whistler waves are enhanced when they pass through the plasma cavity formed during VLF heating process. Key points: The heating region with radius of 2–3° has been detected over NWC transmitter. Ions moved upwards over the heating region with clear decreasing Ne and increasing Te. Ultra-low frequency electric field was detected due to the effects of V ⇀ × B ⇀ . [ABSTRACT FROM AUTHOR]

The prograde metamorphic P–T conditions of eclogites correspond to the subduction processes of oceanic plates. The conditions may be recorded in mineral inclusions and the compositional zoning of garnets, and they play significant roles in revealing the dehydration depth, geothermal structure of the subduction plate and in understanding arc magmatism. The P–T conditions of the Baqing eclogite have been determined previously using traditional geothermobarometers and Ti-in-zircon geothermometers. To obtain more precise prograde metamorphic P–T conditions and details of the Paleo-Tethyan subduction process, we carried out phase equilibrium modeling for a newly collected Baqing eclogite sample. The sample is characterized by well-developed prograde zonings in metamorphic garnets with increasing Mg and decreasing Mn contents from cores to rims, a peak metamorphic mineral assemblage of garnet + omphacite + phengite + rutile + quartz, and a retrograde metamorphic mineral assemblage of amphibole + plagioclase that replaced omphacite. We calculated the peak metamorphic conditions of the Baqing eclogite using the Garnet–Omphacite–Phengite–Quartz thermobarometers to be 26.5 ± 1 kbar and 730 ± 60°C, consistent with the results (23.5–27.5 kbar, 730–750°C) calculated using a P–T pseudosection. The prograde metamorphic P–T conditions were constrained to be ~21.4 kbar and ~580°C using pyrope and grossular isopleths. These results are consistent with previous calculations for the Baqing eclogite. Eclogites of the Central Qiangtang metamorphic belt, the Baqing metamorphic complex, and Changning–Menglian metamorphic belt show parallel P–T paths with different geothermal gradients, that relate to their different protoliths but similar heating and burial processes during Triassic subduction of the Shuanghu Paleo-Tethyan oceanic plate. [ABSTRACT FROM AUTHOR]

As the annual variation of solar activity, the effect of ionospheric heating varies in a solar cycle. In this paper, we research the ionospheric heating at equinox and solstice with the modified SAMI2 model in the year within 23rd solar cycle. We find that except the F10.7 index, which play a critical role in the process of ionospheric heating, has a significant influence on the value of electron density, the distribution of the electron density also matters for the heating effects. In the year of 2003, a strong seasonal dependence can be found. But in other years of the same solar cycle, the seasonal dependence is not obvious. There may be a threshold for the electron density. When the ionospheric background electron density is less than the threshold, the ionospheric heating effects will be obvious. It can produce cavity structure of electron density and arc structure with enhanced electron density. [ABSTRACT FROM AUTHOR]

Electric arc furnace dust (EAFD) formed during steelmaking in electric arc furnace is a hazardous solid waste that is rich in zinc and iron. In our previous study, we realized the efficient extraction and separation of Zn and Fe from EAFD by co-roasting with FeSO 4 ·7H 2 O followed by water leaching processes, which achieved a high extraction rate of Zn (98.79 %) and a low extraction rate of Fe (0.11 %). However, the high temperature would lead to high energy consumption. Therefore, non-isothermal kinetic and isothermal kinetic were exploited in this study to analyze the heating and holding process for further optimizing roasting conditions. The heating process was divided into four reaction stages with different reaction models. Moreover, the holding process was also divided into two reaction stages with the Anti-Jander 3D diffusion model and Z-L-T 3D diffusion model, respectively. The major reactions in the heating and holding process were defined by thermodynamic equilibrium calculations and in situ X-ray diffraction. The rate-determining step was deduced as the desulfurization of Fe 2 (SO 4) 3 with a three-dimensional diffusion reaction model. Aiming to accelerate Fe 2 (SO 4) 3 desulfurization, the insulation conditions of this process were optimized from 675 °C for 3 h to 600 °C for 3 h, significantly reducing energy consumption. [ABSTRACT FROM AUTHOR]

In this paper, we consider an optimal control problem for a system described by a parabolic linear partial differential equation with the Neumann boundary condition. We impose some constraints on the control. The performance functional has the integral form. The control time T is fixed. The initial condition is not given by a known function but belongs to a certain set (incomplete information about the initial state). To obtain optimality conditions for the Neumann problem, a generalization of the Dubovitskii–Milyutin theorem was applied. The problem formulated in this paper describes the process of optimal heating for which we do not have exact information about the initial temperature of the heating object. We also present an example in which admissible controls and one of the initial conditions are given by means of the norm constraints. [ABSTRACT FROM AUTHOR]

Urban energy system planning is vital for cities shifting towards a more sustainable and integrated energy system. Hydrogen is considered one of the most promising solutions in future energy systems. Previous work on hydrogen energy systems predominantly analysed hydrogen models on a national level or only parts of the mobility sector. This indicates a research gap for geospatial models that include multiple sectors in which hydrogen can be used. These models can be used to support decision-making processes around the hydrogen economy in cities. This study presents a holistic model addressing the geospatial modelling of hydrogen demand in urban areas. It proposes a method that integrates a variety of open source data, including geodata, earth observation data and energy data to estimate hydrogen demand top down for the industrial feedstock (steel, ammonia, organic chemistry), process heating, and mobility (buses, trucks, trains, airplanes, ships) sectors. The proposed method can also be extended to different sectors. The method is validated by modelling the hydrogen demand in all German cities and benchmarking it with national studies. This study's results are within the same range as the results of national studies. For this paper, the method is applied for two case studies in Freiburg im Breisgau and Frankfurt am Main. Applying this method in urban areas shows potential hydrogen demand hotspots in these areas. The model's results help policymakers and industry stakeholders make informed decisions about the development of hydrogen infrastructure and facilitate the adoption of hydrogen as a low-carbon energy carrier. Future research could explore the temporal aspects of hydrogen demand and the spatial influence of hydrogen demand on future hydrogen production facilities such as electrolysers. [ABSTRACT FROM AUTHOR]

Molecular cloud (MC) formation is caused by the gravitational collapse mechanism and is significantly affected by radiative heating and cooling processes. This paper analyzes the gravitational instability in strongly coupled clumpy molecular clouds (MCs), under the effects of uniform rotation, magnetic field, and heat-loss functions. The generalized hydrodynamic equations coupled with the modified energy equation (which incorporates the heating and cooling effects due to cloud-cloud collisions) are used to describe the mathematical model. Following Jeans stability analysis, it is found that the value of the critical Jeans wavenumber decreases due to the strong coupling between the plasma particles (coupling parameter) and clump stirring processes (heating rate), so both have a stabilizing influence on the onset of gravitational collapse in clumpy MCs. The influence of various parameters on the growth rate of the instability is discussed numerically, and it is found that the cooling rate parameter that describes cloud-cloud collisions shows a destabilizing effect. The region of instability is observed to be smaller in the strongly coupled clumps (kinetic limit) than in the weakly coupled (hydrodynamic limit) clumps. The results are helpful in understanding the role of heating and cooling mechanisms in the MC formation. [ABSTRACT FROM AUTHOR]

Taking into account the energy crisis and concerns about the effect of burning fossil fuels on the environment, the utilization of renewable energy technologies is being promoted extensively. Despite having significant potential, the feasibility of utilizing solar thermal energy as industrial process heat in Bangladesh is yet to be assessed and this paper aims to fill this research gap. In current work, the viability of utilizing solar thermal energy in Bangladesh for industrial process heating is investigated by parametric analysis considering thermal, economic, and environmental factors. Effect of mass flow rate and inlet temperature on overall heat loss coefficient is studied. The heat gain with respect to the available area for different mass flow rates is presented which can be used as a guideline to determine the capacity of an installed system. A case study is presented for an operational textile factory in Mymensingh to realize the potential of solar industrial process heat using flat plate solar collectors. Energy savings might reach up to 14.7% in summer and around 9% in winter which also leads to reduction of CO2 emission to the same percentage. The payback period has been found to be 13.58 years.

The peculiarities of developing a digital twin for cyberphysical systems using an analytical model of the investigated process are considered. The proposed approach takes into account the conceptual uncertainty of the analytical model parameters with the subsequent passive identification by adapting the analytical model to the dynamic characteristics of the real physical process. In the article, the digital twin development is carried out on the analytical model air heating process example with the help of an electric calorifier. The analytical model uncertain parameters of the electric heater are analyzed and an integral quality index is proposed to evaluate the dynamic model adequacy in the process of air heating. For electric heater model adaptation, the passive identification algorithm of uncertain parameters is developed, in which deviations of the mathematical model uncertain coefficients are minimized. A numerical study of the considered approach has been carried out. It is shown that uncertain parameters' passive identification of the model belongs to the problem of single-extremal optimization. The considered modeling examples confirmed the effectiveness of the proposed approach to digital twins' development for cyber-physical systems. [ABSTRACT FROM AUTHOR]

Salt offers an optimal medium for the permanent isolation of heat‐producing radioactive waste due to its impermeability, high thermal conductivity, and ability to close fractures through creep. A thorough understanding of the thermal‐hydrological‐mechanical (THM) processes, encompassing brine migration, is fundamental for secure radioactive waste disposal within salt formations. At the Waste Isolation Pilot Plant (WIPP), we conducted joint in situ geophysical monitoring experiments during active heating to investigate brine migration near excavations. This experiment incorporated electrical resistivity tomography (ERT) alongside high‐resolution fiber‐optic‐based distributed temperature sensing within a controlled heating experiment. Additionally, discrete element model (DEM) based numerical simulations were conducted to simulate THM processes during heating, providing a more mechanistic understanding of the coupled processes leading to the observed changes in geophysical measurements. During heating, resistivity shifts near the heater were reasonably explained by temperature effects. However, in more distant, cooler regions, the resistivity decrease exceeded predictions based solely on temperature. DEM simulations highlighted brine migration, propelled by pore pressure gradients, as the likely primary factor contributing to the additional resistivity decline beyond temperature effects. The comparison between the predicted ERT responses and observations was much improved when considering the effects of brine migration based on the DEM simulations. These geophysical and simulation findings shed light on brine migration in response to salt heating, enhancing our understanding of the coupled THM processes in salt for safe radioactive waste disposal. Plain Language Summary: Brine migration within a salt nuclear waste repository induces corrosion and the dissolution of radionuclides, influencing their safety. Understanding the impact of waste‐generated heat on fluid dynamics and salt rock deformation is pivotal for the secure disposal of radioactive waste in salt formations. A controlled heating experiment at the Waste Isolation Pilot Plant, New Mexico, was monitored for geophysical changes, including formation resistivity and temperature. Numerical simulations modeled rock behaviors to elucidate the coupled Thermo‐Hydro‐Mechanical processes and their impacts on observed signals. While resistivity changes near the heater were adequately explained by temperature effects alone, more distant and cooler regions exhibited disproportionately larger resistivity decreases. Numerical simulations identified brine migration as the primary cause for this significant decrease, surpassing temperature effects. Incorporating brine migration effects in simulations substantially improved the prediction of resistivity changes. These findings highlight the role of joint geophysical monitoring and numerical simulations for mechanistic understanding of the coupled processes during heating, which is important for safe storage of nuclear waste in salt formations. Key Points: We conducted in situ geophysical monitoring during a controlled heating experiment in salt formationsWhile temperature effects explain resistivity changes near the heater well, more resistivity decreases were observed at the further regionsNumerical simulations indicate pore pressure driven brine migration is likely the primary reason for the resistivity changes beyond temperature effects [ABSTRACT FROM AUTHOR]

In this article, we analyze the spread of information on social media (Twitter) and purpose a strategy based on epidemiological models. It is well known that social media represent a strong tool to spread news and, in particular, fake news, due to the fact that they are free and easy to use. First, we propose an algorithm to create a proper dataset in order to employ the ignorants–spreaders–recovered epidemiological model. Then, we show that to use this model to study the diffusion of real news, parameter estimation is required. We show that it is also possible to accurately predict the evolution of news spread and its peak in terms of the maximum number of people who share it and the time when the peak occurs trough a process of data reduction, i.e., by using only a part of the built dataset to optimize parameters. Numerical results based on the analysis of real news are also provided to confirm the applicability of our proposed model and strategy. [ABSTRACT FROM AUTHOR]

The prediction of weather conditions in the Arctic is important to human activities in the Arctic. Arctic cyclones (ACs), which are extratropical cyclones that originate within the Arctic or move into the Arctic from lower latitudes, can be associated with hazardous weather conditions that may adversely affect human activities. The purpose of this study is to increase understanding of processes that influence the forecast skill of the synoptic-scale flow over the Arctic and of ACs. The 11-member NOAA Global Ensemble Forecast System (GEFS) reforecast dataset, version 2, is utilized to identify periods of low and high forecast skill of the synoptic-scale flow over the Arctic, hereinafter referred to as low-skill and high-skill periods, respectively, during the summers of 2007–17, and to evaluate the forecast skill of ACs during these respective periods. The ERA-Interim dataset is used to examine characteristics of the Arctic environment and characteristics of ACs during low-skill and high-skill periods. The Arctic environment tends to be characterized by more vigorous baroclinic processes and latent heating during low-skill periods relative to high-skill periods. ACs occur more frequently over much of the Arctic; tend to be stronger; and tend to be located in regions of larger lower-tropospheric baroclinicity, lower-to-midtropospheric Eady growth rate (EGR), and latent heating during low-skill periods relative to high-skill periods. ACs during low-skill periods that are characterized by low forecast skill of intensity tend to be relatively strong and tend to be located in regions of relatively large lower-tropospheric baroclinicity, lower-to-midtropospheric EGR, and latent heating. [ABSTRACT FROM AUTHOR]

The effects of microwave (MW) processing and conventional (CV) heating on inactivation of Escherichia coli and Salmonella enterica subsp. enterica, levels of bioactive compounds, antioxidant activity and some health-promoting features of guava juice were investigated. The results showed that MW significantly reduced the time of the process compared to CV heating, so that the time of inactivation of pathogens in MW process was eight times less than the CV method. MW treatment induced a lower reduction in the amounts of total carotenoids, vitamin C, and total phenolics compared to CV heat treatment. MW and CV heating caused losses of 23.99% and 65.52% in DPPH antiradical activity, respectively at the end of the treatment period. In addition, MW-treated samples represented higher enzyme inhibition activities (α-amylase, α-glucosidase, and angiotensin-converting enzyme) compared to CV-treated juices. These findings reveal that MW technology can be used as an alternative to CV heating for processing guava juice in order to ensure microbial safety, reduce process time, save energy, and preserve the essential thermosensitive nutrients. [ABSTRACT FROM AUTHOR]

Research on large-scale energy storage systems has so far been very dedicatedly focused on electricity storage. Even for thermal energy-driven technologies, so-called Carnot batteries, larger electricity output, and higher power-to-power efficiency have been the major concerns. On the other hand, energy storage technologies are mainly useful for helping more renewable energy deployment for which recent studies show that most of the energy sectors are going through a smooth and continuous transition towards sustainability except for the industrial heating and cooling sectors. Therefore, developing energy storage solutions that can potentially contribute to this sector will be precious. This study proposes a multi-generating solar-assisted molten-salt-driven Carnot battery that is used for storing excess electricity of a PV farm in Saudi Arabia and delivering power for grid balancing, steam for process heating, as well as space heating/cooling for several industrial factories. The article presents a detailed techno-economic analysis of the system after making the configuration optimized based on multi-objective optimization techniques. The results show that such a multi-generating solar-assisted molten-salt-driven Carnot battery in the optimized configuration may result in power-to-power, power-to-process heat, and overall efficiencies of 26.82%, 55.78%, and 82.6%. With these performance factors, using standard global prices for electricity and heating, with a process heating cost of higher than 10.15 c$/kWh (which is very realistic), the system will outperform only power-generating Carnot batteries. [ABSTRACT FROM AUTHOR]

Summary: Red‐fleshed dragon fruit is a promising source of antioxidants and natural colour compounds. This study examined the effects of ohmic heating (OH) and ascorbic acid addition on total phenolic content (TPC), betacyanin (BC), antioxidant activity and colour changes in the juice during storage. The juice was treated from 20 to 85 °C and stabilised at 85 °C for 60 s by OH at 60 Hz and 30 V cm−1. The treated samples were stored at 4 °C in dark bottles for 8 weeks, and BC, TPC, antioxidant activity and colour were determined weekly. After 1 week of storage, there was no degradation of TPC or BC (P > 0.05). However, after 8 weeks of storage, BC decreased by 47%, TPC decreased by 60% and antioxidant activity decreased by 39% in the OH juice. The colour changes of the juice during the 8‐week storage period were strongly correlated with the BC (r (correlation coefficient) > 0.98). A comparison of the OH process with conventional heating (CH) showed that OH resulted in less degradation to BC, TPC and antioxidant activity than CH. OH is a suitable technology for processing red‐fleshed dragon fruit juice. Adding 0.25% AA to the juice helped reduce changes in colour, BC, TPC and antioxidant activity (P < 0.05). [ABSTRACT FROM AUTHOR]

Packaging and die bonding of conventional micro‐electro‐mechanical‐systems (MEMS) and semiconductor devices include separate dispensing, mounting and heating curing. A novel die bonder's work stage and temperature control method are proposed so that dispensing, mounting and heating curing can be completed at the same station. This paper introduces the working principle of the thermopile sensor and the requirements for temperature change during die bonding, analyses the main structure and working process of the novel die bonding stage, and uses commercial finite element analysis software to evaluate the temperature field of the novel die bonding stage and devices during the process of heating, holding and cooling to provide process guidance for accurate temperature control of die bonding. Dispensing, mounting and heating curing are integrated in the same station, avoiding the position error of devices when transferring, reducing the number of equipment and floor area, and effectively saving production costs. © 2023 Institute of Electrical Engineer of Japan and Wiley Periodicals LLC. [ABSTRACT FROM AUTHOR]

The 3-D fields of temperature (T) and specific humidity (q) retrieved by instruments such as the Atmospheric Infrared Sounder (AIRS) are predictive of convection, but convection often triggers during the multi-hour gaps between satellite overpasses. Here we fill the hours after AIRS overpasses by treating AIRS retrievals as air parcels which are moved adiabatically along numerical weather prediction (NWP) wind trajectories. The approach is tested in a simulation experiment that samples 3-D European Reanalysis-5 (ERA5) T and q following the real-world AIRS time–space sampling from March–November 2019 over much of the continental US. Our time-resolved product is named ERA5-FCST, in correspondence to the AIRS forecast product we are using it to test, named AIRS-FCST. ERA5-FCST errors may arise since processes such as radiative heating and NWP sub-grid convection are ignored. For bulk atmospheric layers, ERA5-FCST captures 59 %–94 % of local hourly variation in T and q. We then consider the relationship between convective available potential energy (CAPE), convective inhibition (CIN), and ERA5 precipitation. The 1 ∘ latitude–longitude ERA5-FCST grid cells in our highest CAPE and lowest CIN bins are more than 50 times as likely to develop heavy precipitation (> 4 mmhr-1), compared with the baseline probability from randomly selecting a location. This is a substantial improvement compared with using the original CAPE and CIN values at overpass time. The results support the development of similar FCST products for operational atmospheric sounders to provide time-resolved thermodynamics in rapidly changing pre-convective atmospheres. [ABSTRACT FROM AUTHOR]

In recent years, there is a surge of research interest in exotic ferroelectric topological states, motivated by their rich emerging physical properties and potential applications in nanoelectronic devices. Here, we demonstrate the observation of a sort of complex center-type topological domain structures, which exhibit a quadrant center-type (with polarization pointing to the center) topological texture for an in-plane polarization component and a cylinder domain pattern along the vertical direction, in rhombohedral structured Pb(Zr0.7Ti0.3)O3 (R-PZT) nanoislands. Such a center domain state exhibits a rather high stability, which can well maintain its topological texture after heating to above curie temperature and subsequently cooling down to room temperature. Moreover, it allows erasure by a scanning electric field, yet it can also be recovered by a similar heating and cooling process. The observation of these unique topological textures in R-PZT nanoislands might provide a good playground for further exploring their topological phase transition properties, emerging novel functionalities, and application potential. [ABSTRACT FROM AUTHOR]