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Lithium-ion batteries (LIBs) are employed in a range of devices due to their high energy and power density. However, the increased power density of LIBs raises concerns regarding their safety when subjected to external abuse. The thermal behavior is influenced by a number of factors, i.e., the state of charge (SoC), the cell chemistry and the abuse conditions. In this study, three distinct cylindrical Li-ion cells, i.e., lithium nickel cobalt aluminum oxide (NCA), lithium titanate oxide (LTO), and lithium iron phosphate (LFP), were subjected to thermal abuse (heating rate of 5 °C/min) in an air flow reactor, with 100% SoC. Venting and thermal runaway (TR) were recorded in terms of temperature and pressure, while the emitted products (gas, solid, and liquid) were subjected to analysis by FT-IR and ICP-OES. The concentrations of the toxic gases (HF, CO) are significantly in excess of the Immediate Danger to Life or Health Limit (IDLH). Furthermore, it is observed that the solid particles are the result of electrode degradation (metallic nature), whereas the liquid aerosol is derived from the electrolyte solvent. It is therefore evident that in the event of a LIB fire, in order to enhance the safety of the emergency responders, it is necessary to use appropriate personal protective equipment (PPE) in order to minimize exposure to toxic substances, i.e., particles and aerosol. [ABSTRACT FROM AUTHOR]

Clinical trials of hypothermia after pediatric cardiac arrest (CA) have not seen robust improvement in functional outcome, possibly because of the long delay in achieving target temperature. Previous work in infant piglets showed that high nasal airflow, which induces evaporative cooling in the nasal mucosa, reduced regional brain temperature uniformly in half the time needed to reduce body temperature. Here, we evaluated whether initiation of hypothermia with high transnasal airflow provides neuroprotection without adverse effects in the setting of asphyxic CA. Anesthetized piglets underwent sham-operated procedures (n = 7) or asphyxic CA with normothermic recovery (38.5°C; n = 9) or hypothermia initiated by surface cooling at 10 (n = 8) or 120 (n = 7) min or transnasal cooling initiated at 10 (n = 7) or 120 (n = 7) min after resuscitation. Hypothermia was sustained at 34°C with surface cooling until 20 h followed by 6 h of rewarming. At 4 days of recovery, significant neuronal loss occurred in putamen and sensorimotor cortex. Transnasal cooling initiated at 10 min significantly rescued the number of viable neurons in putamen, whereas levels in putamen in other hypothermic groups remained less than sham levels. In sensorimotor cortex, neuronal viability in the four hypothermic groups was not significantly different from the sham group. These results demonstrate that early initiation of high transnasal airflow in a pediatric CA model is effective in protecting vulnerable brain regions. Because of its simplicity, portability, and low cost, transnasal cooling potentially could be deployed in the field or emergency room for early initiation of brain cooling after pediatric CA. NEW & NOTEWORTHY: The onset of therapeutic hypothermia after cardiac resuscitation is often delayed, leading to incomplete neuroprotection. In an infant swine model of asphyxic cardiac arrest, initiation of high transnasal airflow to maximize nasal evaporative cooling produced hypothermia sufficient to provide neuroprotection that was not inferior to body surface cooling. Because of its simplicity and portability, this technique may be of use in the field or emergency room for rapid brain cooling in pediatric cardiac arrest victims. [ABSTRACT FROM AUTHOR]

Bats rely on their hand-wings to execute agile flight maneuvers, to grasp objects, and cradle young. Embedded in the dorsal and ventral membranes of bat wings are microscopic hairs. Past research findings implicate dorsal wing hairs in airflow sensing for flight control, but the function of ventral wing hairs has not been previously investigated. Here, we test the hypothesis that ventral wing hairs carry mechanosensory signals for flight control, prey capture, and handling. To test this hypothesis, we used synchronized high-speed stereo video and audio recordings to quantify flight and echolocation behaviors of big brown bats (Eptesicus fuscus) engaged in an aerial insect capture task. We analyzed prey-capture strategy and performance, along with flight kinematics, before and after depilation of microscopic hairs from the bat's ventral wing and tail membranes. We found that ventral wing hair depilation significantly impaired the bat's prey-capture performance. Interestingly, ventral wing hair depilation also produced increases in the bat's flight speed, an effect previously attributed exclusively to airflow sensing along the dorsal wing surface. These findings demonstrate that microscopic hairs embedded in the ventral wing and tail membranes of insectivorous bats provide mechanosensory feedback for prey handling and flight control. [ABSTRACT FROM AUTHOR]

A novel plasma reactor is being investigated for green NOx production, crucial for nitrate‐based fertilizer manufacturing. Various parameters, including air flow rates, gas ratios, ozone, and catalyst effects are explored for NO → NO2 conversion. NOx concentrations reach ~0.6 vol%, with a total production of ~9.7 gr/h and energy cost of ~3.0 mJ/mol, notably favorable for atmospheric gliding arc plasma. Selectivity (~75%) towards NO2 is achieved with ozone addition or catalytic treatment, pivotal for nitrate fertilizer and HNO3 production. [ABSTRACT FROM AUTHOR]

A numerical investigation for a solar air heater integrated with a multi-section solar distiller has been conducted with a novel design of solar distiller with interior sections. A mathematical description of the solar distiller is made and solved with a MATLAB code. The air flow in the solar air heater, the water height in the solar distiller, and the number of interior sections have all been studied. To validate the numerical system, an experimental system was built. The theoretical model and the experiment performed appear to be in satisfactory correlation. The best working conditions occur when the system is run with a lower air flow rate, a lower saline water height, and a greater number of interior sections with productivity reaching 1242.6 ml/m2 per day, a gain output ratio (GOR) about 0.622 and air heater efficiency about 35%. In the normal case of output salinity between 0 and 500 ppm, the cost was reduced by 96.7%, and by 96.3% in the case of four interior sections. Water cost reduction is also observable at the same output salinity, with 54.1% at 0 ppm and 62.4% at 200 ppm between number of interior sections = 0 and 4. [ABSTRACT FROM AUTHOR]

• Numerical modeling of an integrated refrigerated container. • Different cargo pallet arrangements and cargo packaging boxes are tested. • Airflow short-circuiting has both positive and negative effects on cargo cooling. • Improving vertical airflow in cargo pallets enhances cargo cooling than air gaps. Improving the performance of a refrigerated container is crucial in effectively preserving thermal-sensitive cargo. The combined effect of vertical airflow resistance and airflow short-circuiting in air gaps play a vital role in cargo cooling. This study numerically investigates the effects of cargo vertical airflow resistance and air gaps between cargo pallets using two commonly used apple packaging boxes, each stacked in six different cargo pallet arrangements. A heat transfer enhanced refrigerated container design and a numerical model developed from the present authors' previous studies are used. The numerical model uses the porous medium model to incorporate the refrigeration unit and cargo within the refrigerated container. Additionally, the numerical domain includes the T-bar floor in the refrigerated container. Initially, the airflow characteristics based on vertical airflow resistance and air gaps are discussed. Then, the corresponding effects on cargo cooling are addressed. Results show that the air gaps between the cargo pallets have positive and negative effects on cargo cooling. In cargos with lower vertical airflow resistance, an increase in air gaps leads to reduced cargo cooling and elevated temperature non-uniformity. Conversely, cargos with higher vertical airflow resistance experience increased cooling rates and reduced temperature non-uniformity with the increase in air gaps. However, avoiding airflow short-circuiting through the air gaps between the cargo pallets and improving the vertical airflow inside the cargo pallets can provide better cargo cooling, which outweighs the positive cooling effect of the air gap. [ABSTRACT FROM AUTHOR]

Coal is an essential primary energy for the national economy and people's livelihood. In recent years, with the rapid growth of the consumption of high-quality coal resources, Lignite with a low degree of metamorphism has been extensively exploited and utilized. In this paper, desulfurization and ash reduction treatment of 6–0 mm fine-grade low-grade high-sulfur Lignite was carried out using a FGX dry separation bed (FGX FGX compound dry separation bed). The migration and distribution of differentiated density particles in the bed under the action of cascade air flow were mainly studied, and the influence of vibration intensity (amplitude and frequency) on the separation effect of fine-grade low-grade high-sulfur Lignite was explored. At the same time, the material distribution characteristics of each section in the direction of the discharge edge of the bed were systematically analyzed, the material distribution area of the bed was determined, the optimal operating parameters (A = 2.8 mm, f = 26 Hz, V = 2.29 m/s) were obtained, and the sorting test was carried out under the optimal parameter conditions. The test results show that when the vibration frequency f = 26 Hz, the sulfur segregation degree of bedding materials reaches the maximum Ss = 0.36, and the sulfur content of materials in I, II, and III regions is 0.85%, 5.47%, and 18.78%, respectively. The stratification effect of bedding materials is the best. When A = 2.8 mm, the material sulfur segregation reaches the minimum value of Ss = 0.28, and the average sulfur content of materials in I, II, and III regions is 0.78%, 5.46% and 18.27%, the material is stratified according to density. When the airflow rate is 2.55 m/s. The stratification effect of bed material is best according to density. The clean coal yield is 69.87%, and the sulfur content is 0.98%. The gangue yield is 30.13%, and the sulfur content is 18.66%. The Ep value of energy deviation is 0.11 g/cm3, which realizes high precision dry desulfurization and upgrading fine-grade, low-grade, and high sulfur lignite. [ABSTRACT FROM AUTHOR]

To reveal the evolution characteristics and driving factors of net primary productivity (NPP) of vegetation in arid regions, with Kashi region as a representative case, this study utilized various remote sensing satellite data, including MOD13A1/Q1, MOD09A1, and MOD17A3, to estimate vegetation NPP in the study area from 2001 to 2020 using the CASA model. The study aimed to express the impact of external driving factors on vegetation NPP from the perspectives of climate change and land use change. The results indicated: (1) Over the past two decades, the overall trend of vegetation NPP in the study area exhibited an initial increase, followed by a subsequent decrease. Specifically, from 2001 to 2015, vegetation NPP increased at a rate of 0.303, while from 2016 to 2020, it decreased at a rate of -0.202. (2) Through trend analysis and significance testing using the Sen+MK method, it was found that 37% of the study area showed a significant increasing trend in NPP, while 73% exhibited a decreasing trend. (3) Precipitation in the Kashi region had a stronger correlation with NPP than temperature. In the southwest region, the Pamir Plateau and Karakoram Mountains showed positive correlations with both temperature and precipitation, with warm and moist airflows promoting NPP in high latitudes. (4) )During the period of 2001-2020, Grassland in the study area degraded at the fastest rate, with a change rate of -2.1%, and the largest increase was observed in farmland, with a change rate of 2.7%; the vegetation NPP decreased by a total of 2748.3 TgC, and the study area shows a decreasing trend in the value of vegetation NPP in the future period. [ABSTRACT FROM AUTHOR]

The application of turbulators to improve thermal performance and thermal enhancement in heat exchangers because of the significance of energy management and optimization is one of the interesting topics for researchers. Analysis of aerodynamic turbulator in internal flow has been less discussed in previous studies. Therefore, the present work focuses on the effect of a perforated sphere turbulator in a circular pipe with square, circular, oval, and hexagonal geometry holes on turbulent flow characteristics and thermal performance. These turbulators are placed with equal obstruction against the flow of air passing inside the pipe at Re = 6000–24000 in wall conditions of constant heat flux. Ansys Fluent software is used for numerical solutions, and the results are validated with an experimental paper. According to the results, the hexagonal geometry creates less pressure drop than other geometries. The thermal performance in the pipe with innovative aerodynamic turbulators is improved compared to the smooth pipe and the pipe equipped with conventional turbulators. The highest thermal performance of 1.256 is obtained for the turbulator with an oval hole. Also, the range of Nusselt number compared to the plain pipe for turbulator with circular, hexagonal, square, and oval holes increases by 1.97–2.46, 2.24–2.65, 1.58–1.89, and 2.48–2.81 times, respectively. The effect of the proposed new turbulators was compared with previous studies in this field, and the results are promising. [ABSTRACT FROM AUTHOR]

In recent years, the rehabilitation of spillways and design of new dam constructions have considered the combination of a stepped chute with a labyrinth weir crest, highlighting the need for hydraulic information for this specific spillway type. To address currently missing design guidance, a novel study was conducted on a 10.7° round-crested labyrinth weir with a 3H:1V sloped chute with multiple step heights. The results include guidance for estimating flow depths along the chute and selecting a chute wall height; the role of the labyrinth weir on aeration, streamwise and transverse flow uniformity, and general flow patterns; and energy dissipation by the labyrinth crest and by individual steps. It was found that stepped chutes with a labyrinth crest are aerated from the impact of the nappes in the labyrinth outlet cycles, which continued to the chute entrance where the maximum air concentrations and flow depths occurred. The labyrinth crest also generates nonuniform flow patterns and air-water flow properties that have a significant effect on energy dissipation as the nonuniformity and potential drag reduction (due to the stronger aeration) results in less energy dissipated compared with published literature of stepped spillways with linear crests. The present findings provide first guidance for practitioners to combine labyrinth weirs with stepped chutes. [ABSTRACT FROM AUTHOR]

[Display omitted] • We proposed an SPA based on a Kresling-like pattern with a rigid skeleton by observing the cloning and moving behaviors from salps. • An extensible inserting structure is innovatively designed to replace the creases in traditional Kresling patterns. • The SPA can perform an axial contraction motion without twisting and a controllable bending motion. • The number of layers of Kresling-like patterns is changeable by adding or reducing skeleton components. • The elongation can reach to above 162% and the output force can reach to above 6.36 N. Biomimetic soft pneumatic actuators (SPA) with Kresling origami patterns have unique advantages over conventional rigid robots, owing to their adaptability and safety. Inspired by cloning and moving behaviors observed from salps, we proposed an SPA based on a Kresling-like pattern with a rigid skeleton. The elongation and output force were tested, and the effectiveness of the applications with the SPA was evaluated. The proposed SPA consists of rigid skeletons and a soft skin. The rigid skeletons are constructed using layers of Kresling-like patterns, while a novel extensible inserting structure is devised to replace the folds found in conventional Kresling patterns. This innovative approach ensures that the SPA exhibits axial contraction/expansion motion without any twisting movement. To mimic the bionic characteristics of swimming and ingesting progress of salps, the proposed SPA can perform an axial contraction motion without twisting and a controllable bending motion based on multi-layered Kresling-like patterns; to mimic the cloning and releasing life phenomena of salps, the number of layers of Kresling-like patterns is changeable by adding or reducing skeleton components according to the practical needs. The experimental elongation results on the SPA with multiple layers of Kresling-like patterns show that the elongation can increase to above 162% by adding layers; the experimental output force results show that the three-layer SPA can provide 6.36 N output force at an air flow rate of 10 L/min, and the output force will continue to increase as the number of layers of Kresling-like pattern increases or the air flow rate increases. Further, we demonstrate the applications of the SPA in soft grippers, scissor grippers, claw grippers and pipe crawlers. Our proposed SPA can avoid twisting in the radial contraction motion with high elongation and output force, and provide the practical guidance for bio-inspired soft robotic applications. [ABSTRACT FROM AUTHOR]

Unsteady gas-dynamic phenomena in pipelines of complex configuration are widespread in heat exchange and power equipment. Therefore, studying the heat transfer level of pulsating air flows in round and triangular pipes with different turbulence intensities is a relevant and significant task for the development of science and technology. The studies were conducted on a laboratory stand based on the thermal anemometry method and an automated system for collecting and processing experimental data. Rectilinear round and triangular pipes with identical cross-sectional areas were used in the work. Flow pulsations from 3 to 15.8 Hz were generated by means of a rotating flap. The turbulence intensity (TI) of the pulsating flows varied from 0.03 to 0.15 by installing stationary flat turbulators. The working medium was air with a temperature of 22 ± 1 °C moving at a speed from 5 to 75 m/s. It was established that the presence of gas-dynamic unsteadiness leads to an increase in the TI by 47–72% in a round pipe and by 36–86% in a triangular pipe. The presence of gas-dynamic unsteadiness causes a heat transfer intensification in a round pipe by 26–35.5% and by 24–36% in a triangular pipe. It was shown that a significant increase in the TI of pulsating flows leads to an increase in the heat transfer coefficient by 11–16% in a round pipe and a decrease in the heat transfer coefficient by 7–24% in a triangular pipe. The obtained results can be used in the design of heat exchangers and gas exchange systems in power machines, as well as in the creation of devices and apparatuses of pulse action. [ABSTRACT FROM AUTHOR]

The objective of this study is to implement a more realistic integrated analysis model for micro gas turbines by incorporating secondary flow and combustion efficiency into the existing model, which includes main engine components such as the compressor and turbine, and to validate this model by comparing it with test results. The study was based on the JetCat P300-RX, which has a maximum thrust level of 300 N. Simulations were performed using ANSYS CFX, employing the κ-ω SST turbulence model and a mixing plane interface between individual components. The eddy dissipation model (EDM), with a combustion efficiency of 90%, was used as the combustion model. A user subroutine was also applied for the power matching of the compressor and turbine to calculate the fuel flow rate in each iteration. For secondary flow, it was assumed that 3% of the total air flow rate would flow through the secondary path and be applied to the compressor and turbine. Simulations were conducted over a range of 30,000 to 104,000 RPM, with ground conditions evaluated, including altitude-simulated conditions. To validate the analysis model, engine performance metrics such as pressure ratio, air flow rate, fuel flow rate, and exhaust gas temperature (EGT) were compared with test results. The results demonstrated that errors were less than 5% for most engine performance metrics, except for EGT and fuel flow. The discrepancy in EGT was attributed to differences in the sensing methods, while the variation in fuel flow was found to be due to the lubrication system and losses due to the secondary air flow. Consequently, this study confirmed that the integrated simulation model accurately predicts engine performance. The results indicate that the integrated simulation model provides a more realistic prediction of overall engine performance compared to previous studies. Therefore, it can evaluate detailed thermo-fluid properties without the need for component performance maps, enhancing performance evaluation and analysis. [ABSTRACT FROM AUTHOR]

Copyright of Cotton Textile Technology is the property of Cotton Textile Technology Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Automotive Digest is the property of Automotive Digest Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

The risk of coal spontaneous combustion in goaf is one of the disasters in coal mining, ventilation and extraction often aggravate air leakage from the goaf. Due to the unclear rule of expansion law and air leakage, the risk space for coal spontaneous combustion continues to occur. To investigate the influence of ventilation and extraction on the evolution of the risk space of coal spontaneous combustion (CSC) in goaf, further reveal the characteristics of air leakage and extraction in goaf and obtain the expansion law of CSC risk space. A three-dimensional model of goaf under surface drilling and gas extraction was developed. Using FLUENT numerical simulation software, taking a coal mine in Anhui Province, this study analyzes the influence factors, evolution law, and influence characteristics of CSC through field observations and numerical simulation. The research indicates that ventilation keeps the risk space of CSC expanding. The extraction of single drilling showed a local space expansion, while the extraction of double drilling shows the overall space expansion of the goaf. The air leakage flow path in goaf, air flow velocity vector in working face, gas concentration loss, and gas extraction characteristic parameters are determined. The loss of air leakage along the working surface meets four-stage: "strong in – flow - mixed flow – steady inflow – sudden outflow." It can be determined that the extraction intensity of single drilling should be greater than 34.8 m3/min, and the double drilling should be greater than 18.7 m3/min. The relationship between the coupling influence of ventilation and extraction and the expansion law of CSC risk space is determined, and the maximum risk space width of CSC can be predicted. The research results are of guiding significance for CSC prevention and gas efficient extraction. [ABSTRACT FROM AUTHOR]

Direct air capture (DAC) is a negative emission technology for removing CO2 from the atmosphere to maintain the CO2 level within a reasonable range so as to address greenhouse effects. In this study, the operational optimization of lab‐scale DAC has been investigated using a crossflow air‐liquid contactor loaded with a three dimensionally printed Gyroid packing structure and a potassium sarcosinate solvent. The effects of various parameters, including feed air flow rate, liquid solvent flow rate, contactor geometry, and ambient temperature, are examined. The results demonstrate that the Gyroid packing design achieves comparable CO2 capture performance to conventional packed beds but with a significantly lower pressure drop of up to 77.8%, suggesting its potential as an efficient and cost‐effective solution for gas–liquid contactors in DAC. Additionally, the study explores the climate impact on CO2 capture performance and finds that as the air temperature increases from 35 to 95°F at a fixed relative humidity of 80%, the CO2 capture rate increased from 23.2% to 46.8% with better stability. The research highlights the importance of optimizing contactor design and operational conditions to improve the CO2 capture rate and feasibility of DAC systems as a negative emission technology for addressing greenhouse effects. [ABSTRACT FROM AUTHOR]

Copyright of Cuadernos del Centro de Estudios de Diseño y Comunicación is the property of Cuadernos del Centro de Estudios de Diseno y Comunicacion and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

This paper presents a comparative analysis of a finned heat exchanger fed with synthetic refrigerant R410a and environmentally friendly refrigerant R290. Analyses of the performance of the heat exchanger operating as an evaporator in a refrigeration system were carried out. Simulation studies were performed using SOLIDWORKS software with the Flow Simulation library. The analysis was conducted for various design parameters of the device. The performance of the exchanger was examined for different fin materials (aluminium alloys: alloy 1060, 1060-H12, alloy 2014, alloy 2024), number of fins (78 and 39), and fin spacings (2.5 mm and 5 mm). The studies were conducted under various operational parameters of the exchanger (varying volume flow of air and refrigerant mass flow). Based on the results obtained, it was found that the material of the exchanger does not significantly affect its performance. The next conclusion is that when the heat exchanger is fed with an environmentally friendly refrigerant, the heat transfer surface area can be reduced by 50%. As a result, the reduction in heat transfer surface area can be achieved by increasing the fin spacing, which will reduce the electricity consumed in the defrost process under operating conditions, or by reducing the size of the exchanger, which will positively translate into a reduction in the weight of the refrigerant in the system. The possibility of reducing the dimensions of the heat exchanger by up to 50% indicates that replacing R410a refrigerant with environmentally friendly R290 is a promising direction for development. It advocates for ongoing investigations to refine these systems and maximize the operational advantages presented by natural refrigerants. [ABSTRACT FROM AUTHOR]

Dryland expansion causes widespread water scarcity and biodiversity loss. Although the drying influence of global warming is well established, the role of existing drylands in their own expansion is relatively unknown. In this work, by tracking the air flowing over drylands, we show that the warming and drying of that air contributes to dryland expansion in the downwind direction. As they dry, drylands contribute less moisture and more heat to downwind humid regions, reducing precipitation and increasing atmospheric water demand, which ultimately causes their aridification. In ~40% of the land area that recently transitioned from a humid region into a dryland, self-expansion accounted for ’50% of the observed aridification. Our results corroborate the urgent need for climate change mitigation measures in drylands to decelerate their own expansion. [ABSTRACT FROM AUTHOR]

BACKGROUND RESULTS CONCLUSION The delayed drying of newly harvested tiger nuts can lead to mold and rancidity. Timely drying is therefore important. However, few studies have analyzed the impact of hot‐air drying on the quality of tiger‐nut oil and starch, making it essential to establish optimal drying conditions.The results showed that the drying temperature was the most important factor affecting the drying speed, followed by drying airflow rate and loading capacity. A logarithmic model can describe the hot‐air drying process of tiger nuts. The oil yield of tiger nut was highest after drying at 60 °C, reaching 22.40%. Meanwhile, the starch extracted from after drying at 60 °C had the highest solubility and expansion rate, 4.77% and 9.74%, respectively. Starch has the highest viscosity after drying at 70 °C, and it forms gel easily after aging.High‐quality tiger nuts should be produced under optimal conditions: a hot‐air drying temperature of 60 °C, an airflow rate of 1.0 m s−1, and a loading capacity of 100 g. The results of this study have practical implications for the effective drying of tiger nuts. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

The projected speckle-based three-dimensional digital image correlation method (3D-DIC) is being increasingly used in the reliability measurement of microelectronic packaging structures because of its noninvasive nature, high precision, and low cost. However, during the measurement of the thermal reliability of packaging structures, the thermal airflow generated by heating introduces distortions in the images captured by the DIC measurement system, impacting the accuracy and reliability of noncontact measurements. To address this challenge, a thermal airflow distortion correction model based on the transformer attention mechanism is proposed specifically for the measurement of thermal warpage in microelectronic packaging structures. This model avoids the oversmoothing issue associated with convolutional neural networks and the lack of physical constraints in generative adversarial networks, ensuring the precision of grayscale gradient changes in speckle patterns and minimizing adverse effects on DIC calculation accuracy. By inputting the distorted images captured by the DIC measurement system into the network, corrected images are obtained for 3D-DIC calculations, thus allowing the thermal warpage measurement results of the sample to be acquired. Through experiments measuring topography with customized step block specimens, the effectiveness of the proposed method in improving warpage measurement accuracy is confirmed; this is particularly true when captured images are affected by thermal airflow at 140 °C and 160 °C, temperatures commonly encountered in thermal reliability testing of packaging structures. The method successfully reduces the standard deviation from 9.829 to 5.943 µm and from 12.318 to 6.418 µm, respectively. The results demonstrate the substantial practical value of this method for measuring thermal warpage in microelectronic packaging structures. [ABSTRACT FROM AUTHOR]

With buildings contributing significantly to electricity usage, enabling demand flexibility becomes a challenge, especially when accounting for occupant comfort. This study introduces an innovative co-simulation framework integrating multiple models: heating, ventilation, and air conditioning (HVAC) system, building zone load, indoor airflow, supervisory control, and occupant comfort and behavior. Uniquely, this framework allows for a comprehensive and dynamic analysis of building systems and occupant interactions in demand response events. Using this framework, we conducted a case study using a typical small office building model. Specifically, we focused on three areas: (1) the impact of indoor airflow modeling on energy use, occupant comfort, and behaviors forecasting, (2) the impact of occupant behaviors on demand flexibility, and (3) occupant comfort and behaviors under demand response events. Key performance indicators such as energy use, flexibility factor, durations of occupant discomfort and occupant behaviors were analyzed. Our findings indicated variations in energy usage and occupant comfort within demand flexibility events, marked by uncertainty boundaries, with variability in demand shedding up to 57.9%. We concluded that this framework is suitable for analyzing typical commercial buildings and their HVAC systems in terms of demand flexibility potential under the impact of occupant behaviors. [ABSTRACT FROM AUTHOR]

This study reports satellite evidence for the most northerly blown dust activity yet observed on Earth. A systematic inspection of high‐resolution satellite imagery identified active dust events and their sources >82°N in Peary Land, Greenland. In the absence of any local weather measurements, for all observed dust activity a focus period in April 2020 with multiple dust plumes, reanalysis climate data found the majority of dust events to be associated with wind speeds exceeding a typical threshold value for blowing sand and dust uplift. Wind direction variability points to dust‐raising by cold airflow down‐valley winds, likely from nearby ice masses. [ABSTRACT FROM AUTHOR]

As the important component to guide the airflow in the classifier, installation position of the guide vane determines the width of the classification annular region and influences the flow field distribution. The influence of the guide vane positioning on the flow field in the annular region is analyzed through numerical simulation. The simulation results show the tangential velocities near the inner edge of the guide vanes increase, and the tangential velocity gradient decreases with decrease of the width of the annular region. The increases of turbulent dissipation rate near the guide vanes are beneficial to powder dispersion. However, the increases of turbulent dissipation rate near the rotor cage aren′t conducive to uniformity of the flow field. In case of the narrow annular region, the cut size gradually increases when the width of the annular region increases. However, when the width of the annular region continues to increase, the particle′s residence time become long, and the solid concentration increases significantly to increase the probability of particle aggregation. The reasonable range of the installation diameter of the guide vane in the classifier is between 504 mm and 524 mm. [ABSTRACT FROM AUTHOR]

The unsteady airflow will cause the distortion and delay change of the signal propagation path, resulting in the delay and distortion of the received satellite signal. This will lead to increased ranging and direction finding errors in the positioning system, which will affect the precision and accuracy of the positioning results. Therefore, a new multi-satellite anti-interference hybrid positioning method under the influence of unstable airflow is studied. Preprocess the unstable turbulence data at high altitude, and verify the turbulence data authenticity quickly. The flow field description equation is constructed based on the momentum conservation theorem. The multi-satellite motion equation is established by using the carrier phase observations and satellite antenna phase center coordinates, and the anti-interference hybrid positioning model is constructed. Global Navigation Satellite System (GNSS) technology is introduced to solve the multi-satellite hybrid anti-interference model by using the signals of multiple satellites to calculate the receiver's position, speed and time. The experimental results show that, for static targets, the research method has a small deviation in the positioning of the target N, S and E. When using the mixed positioning of near-earth satellite, medium altitude satellite and geosynchronous satellite, the mean square value of positioning error is always lower than 0.002 cm. For the dynamic target, the method is not disturbed by clutter, and the target is stably located. Moreover, the proposed method has lower localization delay and higher localization efficiency. [ABSTRACT FROM AUTHOR]

uDALES is an open-source multi-physics microscale urban modelling tool, capable of performing large-eddy simulation (LES) of urban airflow, heat transfer, and pollutant dispersion. We present uDALES v2.0, which has two main new features: (1) an improved parallelisation that prepares the codebase for conducting exascale simulations and (2) a conservative immersed boundary method (IBM) suitable for an urban surface that does not need to be aligned with the underlying Cartesian grid. The urban geometry and local topography are incorporated via a triangulated surface with a resolution that is independent of the fluid grid. The IBM developed here includes the use of wall functions to apply surface fluxes, and the exchange of heat and moisture between the surface and the air is conservative by construction. We perform a number of validation simulations, ranging from neutral, coupled internal–external flows and non-neutral cases. We observe close agreement with the relevant literature, both in cases in which the buildings are aligned with the Cartesian grid and when they are at an angle. We introduce a validation case specifically for urban applications, for which we show that supporting non-grid-aligned geometries is crucial when solving surface energy balances, with errors of up to 20 % associated with using a grid-aligned geometry. [ABSTRACT FROM AUTHOR]

In this paper, we present a cost-effective system for monitoring and controlling alkaline electrolyzers, intending to improve hydrogen gas production on a laboratory scale. Our work includes two main innovations. Firstly, we suggest an approach to calibrate a standard air flow meter to accurately measure the flow of hydrogen-rich gas from electrolyzers, improving measurement accuracy while keeping costs low. Secondly, we introduce a unique cascade control method to manage hydrogen-rich gas production in the electrolyzer, ensuring precise control over gas flow rates. By combining affordable, energy-efficient devices with a PI control system, we achieve efficient gas production through electrolysis, replacing manual control approaches. Experimental results confirm the effectiveness of our cascade control method, demonstrating stable operation with minimal errors. These results provide a foundation for further research into control strategies to enhance the performance of electrolytic cells. [ABSTRACT FROM AUTHOR]

In this study, tubes filled with PCM as a thermal energy storage unit with an indirect air heater are used to store and recover solar thermal energy. Two different configurations of PCM-filled tubes (inline and staggered) in the unit are considered and compared with the PCM-filled plate unit. In all cases, the amount of the PCM is the same. The effects of airflow rate, diameter of tubes and inlet temperature on the charging and discharging rates are studied. Results showed that the PCM tube unit is more efficient than the PCM plate unit. The thermal performance is enhanced with the increase of the air mass flow rate. Results also revealed that the phase change rate in staggered configurations is between 7% and 36% (depending on the airflow rate) greater than that in the inline ones. By reducing the tube diameter, the melting and solidification processes are performed more quickly due to the rise of the overall heat transfer surface area. The influence of the temperature difference between the inlet air and PCM is more effective than the other considered effects where the 10 °C increase of the temperature difference enhances the charging rate by a factor of 2. [ABSTRACT FROM AUTHOR]

The oxidation kinetics and oxide scale morphology of the Si 2 BC 3 N/Ta 4 HfC 5 ceramics sintered by hot-pressing were explored at 1000 °C and 1500 °C in flowing air. Dense Si 2 BC 3 N/Ta 4 HfC 5 ceramic sintered at 1900 °C with fine grain sizes shows the optimal oxidation resistance both at 1000 °C and 1500 °C. When oxidized at 1000 °C, the formation of a porous oxide layer of Ta 2 O 5 , Hf 6 Ta 2 O 17 and HfO 2 containing amorphous SiO 2 are primarily responsible for the unsatisfying oxidation resistance of the composite. A highly oxidation resistance component like Si 2 BC 3 N can promote the oxidation resistance of Ta 4 HfC 5 at 1500 °C, thanks to the formation of a dense and continuous tantalum-hafnium silicate glass. The oxidation kinetic curve at 1500 °C can be described by a parabolic law whilst the oxidation process is controlled by the diffusion rate of oxygen through the oxide layer; however, the oxidation reaction rate governs the oxidation progress at 1000 °C via a linear oxidation kinetics. • Different oxide phases of Si 2 BC 3 N/Ta 4 HfC 5 ceramics form when oxidized at 1000 °C and 1500 °C, respectively. • Si 2 BC 3 N/Ta 4 HfC 5 ceramics has a better oxidation resistance than Ta 4 HfC 5 when oxidized at 1500 °C. • Si 2 BC 3 N/Ta 4 HfC 5 ceramic sintered at 1900 °C has the best oxidation resistance because of the fine grain size and good relative density. [ABSTRACT FROM AUTHOR]

Large-span arch greenhouse has gained widespread application in fruit and vegetable production in recent years, due to the convenient facility operation, high land use efficiency, suitability for multiple coverings, and external heat preservation. However, internal turbulence can often occur in the expansion of the span and height of the large-span arch greenhouse. The resulting uniformity of the greenhouse environment can then affect the efficient production of greenhouse crops. In this study, a multi-field coupled computational fluid dynamics (CFD) model was constructed to integrate the facility structure and tomato plant aerodynamics, according to agricultural industry demand. The research object was selected as the 20 m span large-span arch greenhouse in Laiwu district, Jinan City, Shandong province (36.14° N, 117.28° E), China. A systematic investigation was carried out to explore the influence of the height of the arch greenhouse on the spatial and temporal distribution and evolution of the turbulent structure inside the large-span arch greenhouse. An analysis was also made to clarify the relationship between the wind and the temperature distribution, turbulence intensity, summer ventilation, and cooling efficiency, and the height of the arch greenhouse. Seven kinds of large-span arch greenhouse were established with 4.5, 5.0, 5.5, 6.0, 6.5, 7.0 and 7.5 m heights. The results show that there was turbulent behavior in the large-span arch greenhouses, indicating the mostly double vortex in the section. The air-flow entered the greenhouse via the bottom vent on the windward side, then ascended along the lower side of the greenhouse film, and finally descended towards the roof area. There was a tendency for the stabilization in the position of the inflection point, as the ridge height increased beyond 6.0 m. Therefore, the better uniformity of air flow and temperature distribution were, the higher the uniformity of the greenhouse was. The large-span arch greenhouse with a height of 6.0 m shared the highest average flow velocity at the crop canopy, which was in the appropriate range and relatively high. The average temperatures were also relatively low, which were 0.404 ℃ and 0.026 ℃ lower than those of the arch greenhouse with a height of 5.5 and 6.5 m, respectively. The turbulence intensity of the large-span arch greenhouse with a height of 4.5-5.5 m was significantly higher than that with a height of more than 6.0 m. There was a small difference, after the ridge height exceeded 6.0 m. Once the height of the greenhouse was 4.5 m, the ventilation efficiency was 2.24. After that, the efficiency of ventilation decreased with the increase in the height of the greenhouse. There was a relatively high value when the ridge height reached 6.0 and 6.5 m. The ridge height of 7.0 m corresponded to the lowest ventilation efficiency of 1.60. The large span greenhouse with a 4.5 m ridge height exhibited the higher ventilation efficiency, but the lower air change rate. The large span greenhouse with a 7.5 m ridge height shared the lower air change rate and ventilation efficiency. The outstanding ventilation and cooling performance of the large-span arch greenhouse in summer was determined by many factors. In a 20 m long-span arch greenhouse with shoulder, a better structure was achieved with the ridge height of 6.0-6.5 m and the ridge height of 6.0 m, in order to better consider the factors of economy and safety. The finding can provide a strong reference to optimize a similar greenhouse configuration in the construction of the large-span arch greenhouse. [ABSTRACT FROM AUTHOR]

AbstractGarbage incineration power generation is utilized to dispose of multi-source organic solid waste. This work constructed a mathematical model for a 750 t/d garbage incinerator to reveal the coupled response between the boiler and furnace sides. Field experiments validated the model, exploring various operating conditions including different loads, fuel blending ratios, primary air, and internal flue gas recirculation (IGR) air flow rates. Increasing the load by 9.1% raised furnace heat exchange by 4.0% but reduced economizer heat exchange by 19.0%. Introducing waste cloth strips and paper mill waste enhanced furnace water-cooled wall heat transfer but reduced economizer heat exchange. A 10.8% rise in primary air flow increased superheater heat exchange by 7.8%. Similarly, a 21.3% rise in IGR air flow increased economizer heat exchange by 9.0%. The temperature rise and enthalpy rise in the superheater were higher when the low calorific value of the fuel was higher. Increasing primary air velocity enhanced heat transfer, raising the outlet temperature of the medium-temperature superheater, necessitating an increase in secondary water spray to adjust the outlet temperature of the high-temperature superheater. This work provides guidance for the design and practical operation of multi-source solid waste incinerators. [ABSTRACT FROM AUTHOR]

Background: At the time of the COVID-19 pandemic, devastating incidents increased due to frequent oxygen administration to patients. The dangers associated with the use of oxygen, especially through local enrichments and formation of "oxygen clouds", have been well understood for years. Nevertheless, dramatic incidents continue to occur, since fire hazard increases exponentially with oxygen concentrations above 23%. Rescue helicopters are at a particular high risk, because of technical reasons such as oxygen use in a very small space, surrounded by kerosene lines, electronic relays and extremely hot surfaces. Methods: In this study three different sized rescue helicopter models (Airbus H135, H145 and MD902) were examined. Oxygen enrichment in the cabin was measured with an oxymeter during a delivery rate of 15 l/min constant flow for 60 min. Furthermore, the clearance of the enriched atmosphere was tested in different situations and with different ventilation methods. To make the airflow visible, a fog machine was used to fill the helicopter cabin. Results: Oxygen accumulation above 21% was detected in every helicopter. After 10–15 min, the critical 23% threshold was exceeded in all three aircrafts. The highest concentration was detected in the smallest machine (MD902) after 60 min with 27.4%. Moreover, oxygen clouds persisted in the rear and the bottom of the aircrafts, even when the front doors were opened. This was most pronounced in the largest aircraft, the H145 from Airbus Helicopters. Complete and rapid removal of elevated oxygen concentrations was achieved only by cross-ventilation within 1 min. Conclusions: Oxygen should be handled with particular care in rescue helicopters. Adapted checklists and precautions can help to prevent oxygen accumulation, and thus, fatal incidents. To our knowledge, this is the first study, which analyzed oxygen concentrations in different settings in rescue helicopters. [ABSTRACT FROM AUTHOR]

The study analyzed available data series of the Sava River's water temperature measured at the Zagreb gauging station. Official data from the Croatian Meteorological and Hydrological Service (DHMZ) in Zagreb were utilized. Over the 73 years from 1948 to 2020, there are only 53 years with complete measurement records. Despite this limiting fact, it was considered important to analyze the behavior of the Sava River's water temperatures in Zagreb over the past 70 years, during which a significant increase in air temperatures has been observed in the region, particularly in the city of Zagreb. Analyses were conducted on the characteristic (minimum, mean, and maximum) water temperatures over timescales of years, months, and days. The relationship between water temperatures (TW) and air temperatures (TA) measured at the Grič Observatory and the flows (Q) of the Sava River in Zagreb were investigated. A trend of rising water temperatures was observed throughout the entire period from 1948 to 2020, with the intensity significantly increasing in the recent period starting from 1988. The trend of rising air temperatures is the primary driver of the increase in the water temperatures of the Sava River in Zagreb. However, the impact of reduced water flow, especially during the warm season, should not be overlooked. This effect is amplified by the observed trend of decreasing minimum flows of the Sava during the warm season, from June to September. As a result, the most significant rise in water temperatures of the Sava River in Zagreb occurs during prolonged low-water summer periods, particularly in July. A strong trend has been observed in the increasing number of days per year with mean daily water temperatures of the Sava River exceeding 20 °C. This higher water temperature occurs increasingly earlier in the year, lasts longer, and ends later, often extending into September. [ABSTRACT FROM AUTHOR]

Photovoltaic (PV) panels are similar in many aspects to the leaves of trees, both are standing in the Sun to capture the sunlight, however, PV panels get soiled especially in desert areas, while the leaves remain clean to a very good extent. The question is, why leaves remain clean while PV panels get soiled quite easily? The leaves are hanging on the stem of trees and these stems are flexible to motion, such that if the wind blows in any direction over the stem it vibrates allowing any deposited particle to fall off the surface. The objective of this research is to develop a fixation method for PV panels similar to the stems of trees, such that the panel can vibrate as the wind blows in order to minimize dust accumulation. Different fixation methods for the PV panel are designed, and the air flow around the panel is simulated using the CFD package Ansys Fluent. It has been found that a PV panel pivoted at its lower edge, such that it can revolve around the lower edge, together with a vertical wind shield attached to its upper edge and a spring attached at the middle of its backside has the largest vibration amplitude due to the applied wind compared to the other designs. Experiments have been done to infer the influence of the new fixation method of the PV panel on dust accumulation over the panel. After 6 weeks of operation, it has been found that the efficiency of the PV panel that is flexibly fixed has dropped by only 5%, while the efficiency of the panel that is rigidly fixed has dropped by 25%. It can be concluded that a PV panel operating a light post should be fixed on a flexible base that allows the panel to vibrate as the wind blows over it in order to mitigate dust. [ABSTRACT FROM AUTHOR]

Oxygen excess ratio (OER), which is influenced by the air flow input to the cathode, is one of the important factors affecting the performance of fuel cell system. Insufficient oxygen supply will result in a sharp drop in output voltage, while an excessive supply will bring about a large parasitic power load on the air compressor, reducing the net output power of the system and operating efficiency. Both insufficient and excess oxygen supply can adversely affect the operating life of the proton exchange membrane fuel cell (PEMFC). Due to the serious nonlinear, hysteresis, uncertainty and interference in the process of OER control, this paper proposes an OER feedforward control based on extended state observer (ESO) for a PEMFC auxiliary system with the ESO to predict the total disturbance to improve the dynamic response of the system with large time delay utilizing terminal sliding mode control (TSMC). The control strategy is divided into two stages. The first stage constructs an ESO to realize real-time observation of the state variables required for the internal operation of the auxiliary machine system and the PEMFC, and yields the air compressor voltage control signal through terminal sliding mode control. In the second stage, combined with V/f control for the compressor, the transmitted air flow is adjusted, ultimately achieving the goal of changing the OER of the PEMFC and improving operating efficiency. The simulation results show that the proposed control strategy has good anti-interference capabilities, a faster response, and less overshoot. The gas flow transmission in the gas supply system is more robust, the PEMFC operation is safer, and its lifespan is extended. • The control difficulty caused by time delay characteristics of gas transmission in hydrogen production system considering gas-electric coupling is overcome. • The additional ESO can well observe the state variables and external disturbance that cannot be directly measured in the PEMFC system. The closed-loop control based on TSMC of the system is realized more accurately. • This paper considers the situation that when the energy storage system cannot meet the energy demand, PEMFC still wants to provide continuous power output. An adjusting strategy for OER in PEMFC through the electromagnetic effect of air compressor to extend the life span of the PEM fuel cell is proposed. • The proposed OER feedforward control strategy demonstrated superior robustness and fast response characteristics for oxygen excess ratio optimization. [ABSTRACT FROM AUTHOR]

The aim of this research is to conduct an experiment that will evaluate the effect of combining of counter flow air-impinging arrangement and an arc-shaped turbulators over the absorber plate of solar heater. This combination is intended to improve the thermohydraulic performance of the solar air heater. The parameters such as energy transfer and frictional factor are studied at flow Reynolds number varies from 18,000 to 3600, and the influence of a hole jet bore ratio from 0.0430 to 0.109 is considered. At the optimal hole jet bore ratio of 0.0650, the thermo-hydraulic achievement parameter has a value of 1.75, which is the greatest possible value can be attained. When compared to multi-pass V and multiple V roughened solar air heaters based on the THAP, the current work is improved the performance by 55.3 and 32.9%, respectively. Such comparisons clearly demonstrate the superiority of the present work. Furthermore, a relationship is shown between the jet hole bore ratio and the thermohydraulic performance measure, with a maximum divergence of 10%. [ABSTRACT FROM AUTHOR]

This study presents the potential of using a natural ventilation system integrated with different combinations of enhancement techniques. The focus was on the perspective of using such configurations of passive ventilation systems (PVSs) in buildings located in different European cities. This work presents the results of obtaining the level of volumetric air flow rate for considering natural ventilation systems. Furthermore, the influences of local weather conditions (temperature, solar radiation, wind speed) were analyzed. Moreover, the year-round operation of all systems was presented. Also noted was the limitation of using PVSs based on the natural draft effect, additionally assisted by wind turbine ventilators in all European localizations. However, for the cities located in the northern part of Europe, it was confirmed that such a system can still meet minimum hygienic recommendations. It was also noted that a system additionally supported by a solar chimney is a much better solution. The best system was a PVS supported by a wind turbine ventilator and solar chimney integrated with PCM accumulation mass. The system should be additionally supported by waste heat from low-temperature sources. In the presented study, a high potential to reduce CO2 emission from building stock by the recommended system is additionally highlighted. However, there is still a need to analyze the proposed solutions by additional field tests and experimental investigations. [ABSTRACT FROM AUTHOR]

A thermal dynamic disaster in the goaf is one of the most serious coal mine disasters formed by coal spontaneous combustion and gas interweaving. However, the influence of the high-temperature hidden fire source formed in the goaf on the evolution law of thermal dynamic disasters is not clear, and effective prevention and control measures cannot be taken. Therefore, this paper uses the experimental platform of thermal dynamic disaster in the goaf to study the influence of different fire point positions on the development of thermal dynamic disaster in the goaf through a similar simulation experiment of thermal dynamic disaster evolution in the goaf and analyzes the corresponding relationship between temperature and CO concentration in the upper corner. The results show that under different locations of heat source, the high-temperature heat source of coal spontaneous combustion migrates to the air leakage side with sufficient oxygen supply, and an oxygen-poor circle is formed near the ignition point. Under the action of air leakage flow, CH4 accumulates in the deep part of the goaf on the return air side. Due to the increase in coal, part of CH4 is produced, which leads to the increase in concentration of CH4 at the ignition point. Under the action of different heat sources, the changing trend of concentration of CO and temperature in the return air corner is the same, but the temperature change in the return air corner shows a lag compared with the change in the concentration of CO, so concentration monitoring of CO can reflect the evolution process of the fire field in the goaf more quickly than temperature monitoring. [ABSTRACT FROM AUTHOR]

Odours used by insects for foraging and mating are carried by the air. Insects induce airflows around them by flapping their wings, and the distribution of these airflows may strongly influence odour source localisation. The flightless silkworm moth, Bombyx mori, has been a prominent insect model for olfactory research. However, although there have been numerous studies on antenna morphology and its fluid dynamics, neurophysiology, and localisation algorithms, the airflow manipulation of the B. mori by fanning has not been thoroughly investigated. In this study, we performed computational fluid dynamics (CFD) analyses of flapping B. mori to analyse this mechanism in depth. A three-dimensional simulation using reconstructed wing kinematics was used to investigate the effects of B. mori fanning on locomotion and pheromone capture. The fanning of the B. mori was found to generate an aerodynamic force on the scale of its weight through an aerodynamic mechanism similar to that of flying insects. Our simulations further indicate that the B. mori guides particles from its anterior direction within the ~ 60° horizontally by wing fanning. Hence, if it detects pheromones during fanning, the pheromone can be concluded to originate from the direction the head is pointing. The anisotropy in the sampling volume enables the B. mori to orient to the pheromone plume direction. These results provide new insights into insect behaviour and offer design guidelines for robots for odour source localisation. [ABSTRACT FROM AUTHOR]

To predict air traffic flow reasonably, research is conducted in conjunction with complex network link prediction. First, the time series is converted into a visual graph to obtain the topological feature quantity, and then combined with the algorithms based on local information, path, and random walk, the prediction accuracy in different sectors of Sanya is compared. It is found that the RWR0.85 algorithm has the highest prediction accuracy. Due to the fact that link prediction can only predict possible edges and cannot predict nodes, the D-S evidence theory is introduced to predict traffic values, with a maximum prediction accuracy of 99.85%. The results indicate that the combination of complex network link prediction and D-S evidence theory for predicting air traffic flow is feasible and effective, laying a foundation for further in-depth research. [ABSTRACT FROM AUTHOR]

This study aimed to assess the technical feasibility of incorporating selenized Lactobacillus spp. microencapsulated via spray drying into cattle feed. Gum Arabic and maltodextrin were used as encapsulating agents. The encapsulation process was carried out with a drying air flow rate of 1.75 m3/min, inlet air temperature of 90°C, and outlet air temperature of 75°C. The viability of the encapsulated microorganisms and the technological characteristics of the obtained microparticles were evaluated. Microorganisms were incorporated into beef cattle feed to supplement their diet with up to 0.3 mg of Se per kilogram of feed. The encapsulated particles, consisting of a 50/50 ratio of gum Arabic/maltodextrin at a 1:20 proportion of selenized biomass to encapsulant mixture, exhibited superior technical viability for application in beef cattle feed. Supplemented feeds displayed suitable moisture, water activity, and hygroscopicity values, ensuring the preservation of viable microorganisms for up to 5 months of storage, with an approximate count of 4.5 log CFU/g. Therefore, supplementing beef cattle feed with selenized and microencapsulated lactic acid bacteria represents a viable technological alternative, contributing to increased animal protein productivity through proper nutrition. [ABSTRACT FROM AUTHOR]

A compact and versatile tensile apparatus for polymer materials is designed and fabricated. Three distinct stretching modes are developed: constant speed, cyclic, and sinusoidal, with adjustable speeds ranging from 0.001 to 120 mm/s. To capture the true strain of the central region, a high-speed camera has been integrated into the apparatus. The temperature of the sample chamber is controlled by flowing air, enabling a homogeneous temperature in the range of RT ∼200 °C. The apparatus is particularly suitable for a synchrotron beamline. The structural evolution of natural rubber during sinusoidal stretching is investigated by in situ wide-angle x-ray scattering. Scattering patterns, force, clamp position, and sample images are saved simultaneously during stretching. Notably, the results reveal a sinusoidal variation in the crystallinity of crosslinked natural rubber when a sinusoidal strain was applied to the sample. The integration of advanced measurement techniques and controlled experimental conditions ensures the acquisition of reliable and accurate data, providing valuable insights into the structural evolution of materials under dynamic deformation conditions. [ABSTRACT FROM AUTHOR]

The primary heat transfer source in the conventional multi-cylinder drying of paper and board is conduction. Conduction is facilitated by high-tension contact with steam-heated cylinders, while convective drying, the main mass transfer source, operates as heated air flows over the article web in the pockets. This conduction process occurs at elevated temperatures and contact pressures to ensure effective contact between the wet paper web and the heated cylinders. The contact pressures and temperatures of the hot surface significantly influence the conductive drying characteristics. This research paper presents an experimental study that involves designing a simple lab-scale setup with in-situ and continuous sensing capabilities for various commercially available grades of paper and board. Embedded thermocouples measure the temperatures of the heated platen and the sheet, allowing the collection of flux data to determine heat transfer characteristics. The goal of this study is to ascertain the instantaneous contact coefficients for different basis weights as a function of moisture content. The acquired data will provide valuable insights and information toward process development, design, and simulation of the article drying process. [ABSTRACT FROM AUTHOR]

To address the challenge of uneven and inadequate deposition within the canopy and on the lower side of the leaves in vineyards spraying operations, the performance of new prototype air-disturbance sprayers was evaluated. Firstly, the optimal parameter combination under the swing type disturbance mode (SW) was determined through orthogonal analysis. Then, a multivariate variance analysis was employed to compare the performance indicators of SW with those found under the rotating type disturbance modes (anticlockwise rotating AR, and clockwise rotating CR), as well as with the blank control group. It has been confirmed that SW could increase the penetration of droplets within the canopy and obtain the optimal deposition uniformity (58.72%). This mode did not affect the canopy deposition, but it decreased the coverage of droplets on the lower side of the leaves (11.82%). AR achieved a deposition uniformity of 62.06% and could consistently ensure that the coverage of both sides of the leaf was over the threshold of 30%. However, it decreased the canopy deposition. Generally speaking, CR not only significantly increased the canopy deposition, but also improved the deposition uniformity to 60.94% (second only to SW). Although the coverage on the lower side of the leaf for CR (25.41%) has not yet reached the threshold requirement of 30%, it could be anticipated that the implementation of two-sided spraying could effectively solve this deficiency. Therefore, the future positioning of a clockwise rotating turbulence system at the airflow outlet of the air-assisted sprayer will be a valuable choice. • Exploring the effect of novel airflow disturbance methods on canopy deposition. • Spray quality assessed by field orthogonal experiment and multiple comparisons. • Modelling airflow characteristics using CFD to help understand deposition results. • Discussed the effect of airflow turbulence intensity on droplet deposition. [ABSTRACT FROM AUTHOR]

AbstractImproving exergy efficiency is crucial to the drying process, especially in reducing costs and carbon dioxide emissions. A closed-loop drying system with a condenser-reheater system was built and analyzed using a numerical simulation to explore the optimal drying conditions, such as inlet air temperature and the air flow rate. Heat-loss coefficients in the simulation were fitted to experimental measurements. The study found that increasing the inlet temperature led to an increase in energy inflow and exergy loss in the system. With an increase in air flow rate from 0.005 to 0.01 kg/s, the exergy loss of the chamber decreased (0.07–0.04 kW), and the exergy efficiency increased (69–92%). The exergy loss was mainly concentrated in the drying chamber, that is, the drying process, and the newly connected condenser and reheater had good exergy efficiencies, exceeding 60%. [ABSTRACT FROM AUTHOR]

Electric motors with high-power densities are required for the implementation of electromobility. To achieve this, direct liquid cooling methods are increasingly being considered, in which oil is injected into the motor compartment. This results in a two-phase flow that can be used for efficient cooling. However, the oil, which can also penetrate the air gap between the rotor and stator, can also lead to additional losses due to increased friction. Since little is known about the two-phase flow in such systems, especially in the air gap, it is investigated by means of simple optical visualizations and high-speed laser-induced fluorescence imaging as well as torque measurements. The measurements are carried out in the air gap of an optically accessible generic model of a directly cooled electric motor. Speed variations were performed from 100 to 2000 rpm, and three different two-phase flow regimes were observed. At low speeds (Flow Regime 1), the air gap is filled locally with oil in radial direction, in the medium speed range (Flow Regime 2) with foam, while at high speeds (Flow Regime 3) separated films were observed on the rotor and stator. The torque difference between the two-phase and single-phase operation, which quantifies the mechanical losses due to the injected oil, increased continuously due to the oil in the air gap until it reached a maximum in Flow Regime 2 due to foam formation. In Flow Regime 3, the torque difference was negative. This was attributed to the fact that the grooves in the stator were filled with oil, thus reducing the turbulence generation of the air flow. [ABSTRACT FROM AUTHOR]

Atmospheric convection across the northern inter-Americas is modulated by trade-wind subsidence and subtropical easterly waves from June to October. Northward migration of the equatorial trough is coupled to the meridional circulation (MC) and surface temperatures above 27ºC. Forming a MC index via S-N height sections of total and anomalous streamfunction, statistical relationships are examined which focus on Jun-Oct season when the South American monsoon is quiescent. Both east Pacific and tropical north Atlantic exhibit cool ocean – dry atmosphere response to an intensified MC. During periods of faster MC, composite humidity is depleted over the Caribbean 10–25 N in conjunction with westerly wind shear, thereby limiting atmospheric convection. The ocean response to intensified MC is evaporative cooling and a deep layer of increased salinity in the Caribbean, that may sustain anomalous air-sea interactions. Long-term trends reveal intensification of the MC in boreal summer: rising over the Amazon, subsiding over the Caribbean, inter-connected by lower and upper airflows. The annually pulsed MC conspires with inter-decadal trends to produce many of the features presented. [ABSTRACT FROM AUTHOR]

Part of the gaseous carbon dioxide (CO2) produced in karst soils / epikarst is transported into underground cavities / caves during the growing season by advective flux, diffusive flux, and flux associated with degassing of seeping water. In dynamic caves, accumulated CO2 is released into the outside atmosphere during the autumn-winter period through advective flux associated with ventilation of the cave in the upward airflow mode. This case study from the Moravian Karst (MK) showed that the net weight of CO2 released annually from the Sloup-Šošůvka Caves (total volume of 131,580 m3 and a total area of 17,950 m2) into the external atmosphere was 348 kg. Extrapolating this value to all known MK caves (area about 352,080 m2) yielded a total of CO2 flux of 6820 kg yr−1. This flux is representing only 0.024‰ of the annual soil respiration from entire MK area (about 2.81 × 108 kg CO2 yr−1). [ABSTRACT FROM AUTHOR]

The inflatable membrane reentry vehicle (IMRV) is one of the innovative aircrafts for next-generation space transport systems because of its reduced aerodynamic heating. In this study, a three-dimensional (3D) thermochemical nonequilibrium model is developed for simulating air plasma flows around an IMRV. This 3D nonequilibrium model includes the coupling of Navier–Stokes equations, 11 species, and 20 chemical reactions of air, a two-temperature model, and shear stress transfer k–ω turbulent transport equations. The simulated results are validated and compared with the corresponding experimental and numerical data published. Generally, they agree well with each other. It is concluded that the flight attack angle of the IMRV has an important impact on the flight stability. When the IMRV flies at an angle of attack of 0°, the translational-rotational and vibrational-electronic temperatures increase rapidly in the surge layer and decrease gradually near the wall. The wall pressure and heat flux decrease gradually along the capsule from the head to the inflatable film, increase rapidly where the inflatable film joins the rings, and decrease rapidly after the shoulder. The chemical and thermal nonequilibrium model developed in this study might be an accurate, stable, and low-cost modeling tool required for the optimal design of hypersonic reentry vehicles. [ABSTRACT FROM AUTHOR]