Moisture Diffusion Research Articles

Application of terahertz technology in detecting dynamic moisture diffusion behavior within the oil-impregnated insulating pressboard

Application of terahertz technology in detecting dynamic moisture diffusion behavior within the oil-impregnated insulating pressboard

Assessing thermal and economic performance of solar dryers in sustainable strategies for bottle gourd and tomato preservation.

The traditional approach of open-sun drying is facing contemporary challenges arising from the widespread adoption of energy-intensive methods and the quality of drying. In response, solar dryers have emerged as a sustainable alternative, utilizing solar thermal energy to effectively dehydrate vegetables. This study investigates the performance of a single-basin, double-slope solar dryer utilizing natural convection for drying bottle gourds and tomatoes, presenting a sustainable alternative to traditional open-sun drying. The solar dryer exhibited superior moisture removal efficiency, achieving a 94.42% reduction in tomatoes and 83.87% in bottle gourds, compared to open-sun drying. Drying rates were significantly enhanced, with maximum air and plate temperatures reaching 54.42°C and 63.38°C, respectively, accelerating the dehydration process. Moisture diffusivity analysis revealed a marked improvement in drying behavior under solar drying, with values ranging from 3.12 × 10-11 to 4.31 × 10-11 m2/s for bottle gourds, and 4.65 × 10-11 to 2.31 × 10-11 m2/s for tomatoes. Energy efficiency assessments highlighted the solar dryer's advantage, with exergy efficiency peaking at 61.78% for bottle gourds and 68.5% for tomatoes. Furthermore, the activation energy required for drying was significantly lower in the solar dryer (29.14-46.41kJ/mol for bottle gourds and 27.16-55.42kJ/mol for tomatoes) compared to open-sun drying, enhancing energy conservation. Visual inspections confirmed the superior quality of the solar-dried vegetables, free from dust and impurities. An economic analysis underscored the system's viability, with payback periods of 2 years for bottle gourds and 1.6 years for tomatoes. Overall, this study demonstrates the efficacy of solar dryers in optimizing vegetable preservation while promoting energy efficiency, aligning with global sustainability goals by reducing post-harvest losses and supporting eco-friendly practices.

Tribological and Hygroscopic Behavior of Polybutylene Terephthalate/Acrylonitrile Styrene Acrylate (PBT/ASA) Nanocomposites with Graphene Nanofiller

Fogging in automotive headlamps is a significant issue that affects both aesthetics and functionality. This study investigates the use of graphene-based nanocomposites to mitigate fogging by enhancing the hygroscopic properties of polybutylene terephthalate/acrylonitrile styrene acrylate (PBT/ASA) composites commonly used in headlamps. The incorporation of functionalized graphene improved the tensile and flexural strength of the nanocomposites, though it led to a reduction in elongation and melt flow. Additionally, the solid lubrication properties and increased surface hardness of the graphene contributed to enhanced wear resistance. The presence of graphene in the nanocomposites also reduced moisture diffusion, lowering the rates of both hygroscopic and desorption when compared to commercial PBT/ASA composites. Furthermore, the nanocomposites exhibited a reduction in maximum moisture uptake. These improvements are expected to reduce the absolute humidity inside the headlamp, thereby effectively mitigating the fogging issue.

Process Modeling and Convective Drying Optimization of Raspberry Pomace as a Fiber-Rich Functional Ingredient: Effect on Techno-Functional and Bioactive Properties

This study aimed to transform raspberry pomace, a by-product of the berry industry, into a sustainable, fiber-rich functional ingredient using convective drying. Drying experiments were conducted at temperatures of 50, 60, 70, 80, and 90 °C to identify the optimal conditions that balance process efficiency and preservation of functional and bioactive properties. The best results were achieved at 70 °C, where a high drying rate (DR) of 0.46 kg H2O·kg−1 db·min−1, effective moisture diffusivity (Deff) of 1.53 × 10−10 m2·s−1, and activation energy (Ea) of 34.90 kJ·mol−1 were observed. The Page model accurately represented the drying behavior (R2 = 0.9965−0.9997). Total dietary fiber (TDF) content remained stable across temperatures (52.52–64.76 g·100 g−1 db), while soluble dietary fiber (SDF) increased by 43.40%, resulting in a solubility (SOL) of 71.8%, water-holding capacity (WHC) of 8.2 mL·g−1 db, and oil-holding capacity (OHC) of 3.0 mL·g−1 db. High retention of bioactive compounds was achieved at 70 °C, including phenolics (32.10 mg GAE·g−1 db) and anthocyanins (25.84 mg C3G·g−1 db), resulting in significant antioxidant activities (DPPH: 33.29 mg AAE·g−1 db, IC50 0.016 mg·mL−1; ABTS: 35.85 mg AAE·g−1 db, IC50 0.029 mg·mL−1). These findings demonstrated the potential of convective drying at 70 °C to efficiently transform raspberry pomace into a high-quality functional ingredient. This process promotes sustainable production and waste reduction in the berry industry.

Investigation of drying kinetics, color, and rehydration parameters of broccoli florets dried with infrared radiation following blanching pretreatment

In order to reduce the drying time of broccoli and to investigate rehydration and color changes associated with the drying process, infrared drying method and blanching pretreatment were used in this study. Boccoli florets were dried using infrared drying at power levels of 50, 62, 74 and 88 W to investigate drying kinetics. Blanching was used as a pretreatment and it was found that the blanched samples dried faster. Effective moisture diffusion coefficients were also calculated. While Deff values between 9.26 × 10−11 and 2.15 × 10−10 m2/s were observed for the control samples, this value varied between 1.10 × 10−10 and 2.87 × 10−10 m2/s for the blanched samples. The calculated activation energy values for the blanched and control samples are 2.11 and 2.0 kW/kg, respectively. The drying process was modeled using 12 different thin-layer drying models and it was found that the Midilli & Kucuk model best represented the process. Color analysis was performed by measuring L, a and b values as well as chroma, hue angle and total color change values. It was observed that increasing infrared power affected color parameters, leading to a decrease in L values and an increase in a and b values. In addition, blanching pretreatment preserved color to some extent. The rehydration behavior of dried samples was also analyzed. It was found that the highest rehydration capacity was achieved in blanched samples dried at 74 W.

An innovative method for mesoscale modelling of moisture diffusion in concrete

Moisture diffusion influences the durability and long-term performance of concrete and whilst it predominantly occurs via the cement matrix and Interfacial Transition Zone, most existing models consider concrete to be homogeneous. This paper introduces a novel micro-meso model that employs random packing and Voronoi tessellation. Rayleigh-Ritz pore distribution and Brunauer-Skalny-Bodor models are combined to determine the radius and fraction of various pores. The results indicate that relative humidity diffuses faster with increasing temperature, decreasing ambient relative humidity and tortuosity. Ambient relative humidity has a greater influence on diffusion compared to temperature and tortuosity. Numerical and experimental comparisons demonstrate that the proposed methodology effectively captures relative humidity distribution across various scenarios. Furthermore, explicit pore network modelling incorporates key parameters for a more accurate analysis. Integrating the proposed methodology into a fully coupled hygro-mechanical framework can potentially yield more accurate predictions of mechanical behaviour; enhancing the reliability of long-term performance assessments and enabling more durable concrete design.

The effect of cold plasma pretreatment on drying efficiency of beetroot by intermittent microwave-hot air (IMHA) hybrid dryer method: Assessing drying kinetic, physical properties, and microstructure of the product

This study examined the effects of cold plasma (CP) pretreatment with durations of 1, 3, and 5 minutes on drying kinetics, microstructure, and physical properties, including shrinkage, rehydration ratio (RR), and bulk density of beetroot dried samples using intermittent microwave-hot air (IMHA) drying at 40 °C and pulse ratios (PR) of 1 and 2. While increasing PR decreased drying rate (DR) and effective moisture diffusivity (Deff), increasing microwave power from 180 to 600 W increased both, reducing drying time and specific energy consumption (SEC). Extended CP-pretreatment doubled DR, 66% increased Deff, and 24% reduced SEC. Both increasing CP-pretreatment time and microwave power had similar effects on shrinkage, RR, and bulk density, but CP-pretreatment was more prominent; reducing shrinkage by 18%, bulk density by 23%, and increasing RR by approximately 36% in 5-minutes. X-ray imaging showed that 600 W of microwave power increased porosity by 87%, while 5-minute CP-pretreatment increased it by 27%. As the optimum condition, CP-pretreatment for 5 minutes, continuous microwave application, and 600 W of MW power produced the best kinetics and physical properties. Overall, the results demonstrated that the appropriate CP-pretreatment duration could produce high-quality dried samples.

Inverse Problem for the Moisture Transfer Equation: Development of a Method for Finding the Unknown Parameter and Proof of the Convergence of the Iterative Process

This study develops a mathematical model for soil moisture diffusion, addressing the inverse problem of determining both the diffusion coefficient and the variation coefficient in a nonlinear moisture transfer equation. The model incorporates specific boundary and initial conditions and utilizes experimentally measured moisture values at a boundary point as input data. An iterative method, based on an explicit gradient scheme, is introduced to estimate the soil parameters. The initial boundary value problem is discretized, leading to a difference analog and the formulation of a conjugate difference problem. Iterative formulas for calculating the unknown parameters are derived, with a priori estimates ensuring the convergence of the iterative process. Additionally, the research establishes the convergence of the numerical model itself, providing a rigorous foundation for the proposed approach. The study also emphasizes symmetry in moisture calculations, ensuring consistency regardless of the calculation direction (from right to left or left to right) and confirming that moisture distribution remains symmetric within specified intervals. This preservation of symmetry enhances the model’s robustness and accuracy in parameter estimation. The numerical simulations were successfully conducted over a 7-day period, demonstrating the model’s reliability. The discrepancy between the numerical predictions and experimental observations remained within the margin of measurement error, confirming the model’s accuracy.

Simulation of Transport Phenomena for Microwave Freeze‐Drying of Potato Slices Using Finite Element Analysis

ABSTRACTThis research intended to investigate the transport phenomena that occur during microwave freeze‐drying (MFD) of potato slices using drying kinetics and finite element analysis (FEA). The impacts of microwave power levels and potato slice thickness on drying rate constant (DR) and average moisture diffusion (DAVG) were analyzed using MFD kinetics and were then incorporated in the simulation. It was found that the DR and DAVG were in the range of 301.3 × 10−3–775.4 × 10−3 min−1 and 1.045 × 10−10–3.336 × 10−10 m2/s, respectively. In the sublimation phase, the DR and DAVG were higher than those in the desorption phase. The DR and DAVG increased as the microwave power level increased but decreased as the thickness increased. The FEA of temperature and moisture distribution within the potato slices demonstrated the outward transfer of heat and mass from the center to the exterior and closely matched the experimental data with an error margin of within 5%, leading to the proposed schematic shrinkage model corresponding to the MFD simulation.

A numerical investigation on the conductive drying process for phosphate sludge

Phosphate production generates huge quantities of waste materials that pose both economic and environmental challenges. They are characterized by a high-water content, making disposal a very difficult task. To address this issue, conductive drying emerges as a viable solution to reduce the water content in the phosphate sludge to facilitate handling and specially recycling them as construction materials. This paper presents a simplified numerical model based on Fick's law, depicting heat and mass transfer in porous media to simulate the conductive drying process within the phosphate sludge. To provide more accuracy to the numerical model solution, the experimental data are integrated into the numerical model as boundary conditions, enabling the prediction of temperature profiles, thermal conductivity, and effective moisture diffusivity throughout the conductive drying process. The water evaporation capacity is found between 1.25 and 2.1 kg water/m2.h.These findings could be a tool for designing a suitable dryer for phosphate washing sludge.

Drying Kinetics of Banana Chips: A Modeling Approach

The primary goal of this research is to identify and evaluate the most suitable thin-layer drying model to effectively interpret the drying characteristics of banana chips and determine moisture diffusivity at different drying temperatures. The study utilized physiologically mature “kapok” bananas from the local market in Jember Regency. A flash dryer with a 4000-watt electric heating system was used, equipped with a blower for air circulation, an exhaust fan to expel water vapor. The bananas were processed into chips with a thickness of 1 mm. A total of 2000 g of banana chips were dried at constant temperature according to treatment conditions (air velocity 3.2 m/s, drying at temperatures of 60, 70, and 80°C). The study found that higher drying temperatures (80°C) achieved the highest initial drying rate (35.9% in 30 min) compared to 60°C (28.0%) and 70°C (22.0%). However, the drying rate gradually decreased at all temperatures. The drying kinetics of banana chips at 60, 70, and 80°C aligned well with the modified Midilli model. Effective moisture diffusivity values for banana chips at 60, 70, and 80°C were 4.947E-9 m²/s, 5.165(10–9) m²/s, and 5.756(10–9) m²/s, respectively, indicating that drying at 80°C was the most effective. The effective moisture diffusivity value showed a strong correlation with air velocity, drying temperature, material thickness, RH, and specific material attributes. Keywords: Banana, Diffusivity, Drying, Thin layer drying, Modified Midilli Model.

Experimental study and mathematical modeling of drying kinetics of mint leaves under forced convection

In this study, we investigated the influence of temperature and air velocity on the drying behavior of Mentha spicata L. leaves using a forced convection dryer. This drying method was chosen for its cost-effectiveness and its ability to facilitate fast and efficient drying while preserving the quality of aromatic herbs. Our aim was to identify the most suitable mathematical model for accurately representing the drying process. We analyzed experimental data on moisture content obtained during thin-layer drying of Mentha spicata L. using various established empirical models from existing literature. Thirteen empirical models were applied to fit the drying curves obtained. Statistical analysis, employing key parameters such as the coefficient of determination (R2), reduced chi-square (χ2), and root mean square error (RMSE), indicated that the Midilli and Kucuk model provided the most accurate fit for the observed drying curves. This was evidenced by the highest R2 values (0.9994, 1.0000), lowest χ2 values (6.07 × 10−6, 6.28 × 10−5), and lowest RMSE values (2.17 × 10−3, 6.86 × 10−3). We observed an increasing trend in moisture diffusivity with temperature variations between 32 °C and 60 °C, while maintaining a constant airflow velocity of 1.2 m/s. Additionally, an increase in mean air velocity from 0.7 to 1.7 m/s correlated with higher moisture diffusivity. The effectiveness of the Arrhenius equation in representing the temperature dependence of diffusivity was confirmed, with an activation energy of 72 kJ/mol, consistent with previous literature findings.

Drying kinetics and thermo-environmental analysis of a PV-operated tracking indirect solar dryer for tomato slices.

The purpose of this study is to investigate how a tracking indirect solar dryer (SD) powered by photovoltaic cells affected the drying kinetics (DK) and thermo-environmental conditions of tomato slices. In this current investigation, three air speeds (1, 1.5, and 2 m/s) are used, as well as three slice thicknesses (ST) (4, 6, and 8 mm) and two SD, one of which is integrated with fixed collector motion (FCM) and another with SD tracking collector motion (TCM). The obtained results showed that the drying time (DT) isn't significantly change with increasing air speeds from 1 to 2 m/s, this may be due to many reasons such as short DT, high temperature inside drying room, and little difference between the exanimated air speeds. When the ST is changed from 4 to 8 mm and maintaining constant air speeds, the DT for FCM and TCM rose by roughly 1.667 and 1.6 times, respectively. In addition, the drying coefficient of the TCM is higher than the FCM due to higher temperature. At 1.5 m/s air speed and 8 mm ST, the maximum values of moisture diffusivity (MD) are 7.15×10-10 and 9.30×10-10 m2/s for both FCM and TCM systems, respectively. During the study of DK, nine drying models and chose the best based on higher R2 and lower χ2 and RMSE are used. The findings of the DK analysis revealed that the modified two term II model fit the experimental data of various air speeds well when TF was dried using TCM and FCM systems at varying ST. These findings are based on recorded observations. Where the models' R2 values varied from 0.98005 to 0.99942 for FCM system and varied from 0.99386 to 0.99976 for TCM system. Regarding environmental analysis, it is found that the CO2 mitigation per lifetime is ranged between 5334.9-6795.4 tons for FCM and 6305.7-6323.3 tons for TCM.

Assessment of a LPG hybrid solar dryer assisted with smart air circulation system for drying basil leaves

The fluctuation of solar radiation throughout the day presents a significant obstacle to the widespread adoption of solar dryers for the dehydration of agricultural products, particularly those that are sensitive to high temperatures, such as basil leaf drying during the winter season. Consequently, this recent study sought to address the limitations of solar-powered dryers by implementing a hybrid drying system that harnesses both solar energy and liquid petroleum gas (LPG). Furthermore, an innovative automatic electronic unit was integrated to facilitate the circulation of air between the drying chamber and the ambient environment. Considering the solar radiation status in Egypt, an LPG hybrid solar dryer has been developed to be suitable for both sunny and cloudy weather conditions. This hybrid solar dryer (HSD) uses indirect forced convection and a controlled auxiliary heating system (LPG) to regulate both temperature and relative humidity, resulting in increased drying rates, reduced energy consumption, and the production of high-quality dried products. The HSD was tested and evaluated for drying basil leaves at three different temperatures of50, 55, and 60 °C and three air changing rates of 70, 80, and 90%, during both summer and winter sessions. The obtained results showed that drying basil at a temperature of 60 °C and an air changing rate of 90% led to a decrease in the drying time by about 35.71% and 35.56% in summer and winter, respectively, where summer drying took 135–210 min and winter drying took 145–225 min to reach equilibrium moisture content (MC). Additionally, the effective moisture diffusivity ranged from 5.25 to 9.06 × 10− 9 m2/s, where higher values of effective moisture diffusivity (EMD) were increased with increasing both drying temperatures and air change rates. Furthermore, the activation energy decreased from 16.557 to 25.182 kJ/mol to 1.945–15.366 kJ/mol for the winter and summer sessions, respectively. On the other hand, the analysis of thin-layer kinetic showed that the Modified Midilli II model has a higher coefficient of determination R2, the lowest χ2, and the lowest root mean square error (RMSE) compared to the other models of both winter and summer sessions. Finally, the LPG hybrid solar dryer can be used for drying a wide range of agricultural products, and it is more efficient for drying medicinal plants. This innovative dryer utilizes a combination of LPG and solar energy, making it efficient and environmentally friendly.

Artificial intelligence as a tool for predicting the quality attributes of garlic (Allium sativum L.) slices during continuous infrared-assisted hot air drying.

Effective drying methods are a highly suitable solution for ensuring stable food supply chains, reducing postharvest agricultural losses, and preventing the spoilage of perishable fruits and vegetables. Moreover, machine learning techniques are innovative and dependable, especially in addressing food spoilage and optimizing drying processes. This study utilized a continuous infrared (IR) hot air dryer to dry garlic (Allium sativum L.) slices. The experiments were conducted at different levels of IR power, air velocities (V), and temperature (T). The relationships between the input process parameters (IR, T, and V) and response parameters, including effective moisture diffusivity (Deff), drying time, and physicochemical properties of the dried slices (rehydration ratio [RR], total color change, flavor strength, and allicin content in the garlic), were modeled using an artificial neural network (ANN). Our findings showed that the maximum Deff of 6.8×10-10m2/s and minimum drying time of 225min were achieved with an IR of 3000W/m2, an air velocity of 0.7m/s, and a temperature of 60°C. The total color change and RR values increased with IR and higher air temperature but declined with higher air velocity. Furthermore, the garlic's flavor strength and allicin content levels decreased as the IR and air temperature increased. The results demonstrated a significant influence of the independent parameters on the response parameters (p<0.01). Interestingly, the ANN predictions closely matched the test data sets, providing valuable insights for understanding and controlling the factors affecting drying behaviors.

Drying Kinetics and Sorption Isotherms of Biocomposite Materials: Experimental Investigation and Modeling Analysis.

Modern materials science has made significant progress in creating new materials and processes for waste recovery. One such advancement involves the development of a new porous composite material made from clay and an environmentally sustainable eggshell powder. In this study, the dynamic behavior of water vapor during desorption and adsorption processes within this composite material was investigated. The moisture diffusivity coefficient was determined within the clay/eggshell powder composite material. The drying kinetic data were analyzed using various models such as Newton, Page, and Wan and Singh. The static gravimetric vapor adsorption/desorption experiments were conducted at different temperatures (30, 40, 50, 60, and 70 °C) to depict the material's capacity for absorbing and releasing moisture over time. The experimental isotherm data were fitted using different mathematical models (Guggenheim, Anderson, and De Boer, Peleg, Adam and Shove, Oswin, and Modified Henderson). The findings suggest that integrating eggshell powder with clay can significantly influence the behavior and characteristics of the resultant material. The combination of eggshell powder and clay reduces moisture sorption and accelerates the drying process. Consequently, this affects the porosity, permeability, and response to humidity changes.

Analysis of the interaction between airflow and high-voltage electric fields on drying characteristics of carrots using heat pump-electrohydrodynamics combined drying

The study investigates the drying characteristics of carrots under different coupling forms of airflow and high-voltage electric fields (parallel flow, PF, and cross flow, CF) using heat pump-electrohydrodynamics (EHD) combined drying. The results show that, compared to single heat pump drying, the combined drying under PF mode reduces carrot drying time by 13.33 %–31.58 %, increases effective moisture diffusivity (Deff) by 17.80 %–32.32 %, increases specific moisture extraction rate (SMER) by 12.25 %–34.26 %. While the combined drying under CF mode reduces carrot drying time by 12.5 %–18.18 %, increases Deff by 7.27 %–13.14 %, increases SMER by 4.64 %–12.58 %. The improvements in parameters under the CF mode are weaker than those under the PF mode. Additionally, the β-carotene content under PF mode is consistently higher than under CF mode. Based on the experimental results, the Modified Page model was improved, yielding an updated model MR = aexp(-(kt)^n), with an R2 value of up to 0.9999–1, which provides theoretical guidance for optimizing the heat pump-EHD combined drying process.

Obtaining a fiber-rich ingredient from blueberry pomace through convective drying: Process modeling and its impact on techno-functional and bioactive properties

This study aimed to optimize the convective drying of blueberry pomace (BP) to enhance fiber functionality and bioactive compound retention. BP was dried at 50−90 °C with an airflow of 2.5 m s−1. Drying kinetics were modeled using five mathematical models, with the Page model showing the highest accuracy (R2 = 0.9965−0.9996). Higher temperatures increased drying rates (3.7 × 10−3 to 1.2 × 10−2 kg H2O kg−1 db min−1) and moisture diffusivity (4.00 × 10−8 to 2.17 × 10−7 m2 s−1), with an activation energy of 39.55 kJ mol−1. Total dietary fiber remained stable (20.85 ± 0.17 g 100 g−1 db), while soluble fiber increased (3.11–4.66 g 100 g−1 db) with temperature. Water- and oil-holding capacities decreased (10.86–8.61 mL g−1 db and 3.85 to 3.44 mL g−1 db, respectively). The highest total phenolic content (13.65 ± 0.12 mg GAE g−1 db) and antioxidant activity (6.65 mg AAE g−1 db for DPPH) were observed at 70 °C. Energy consumption decreased significantly (13.88–6.95 kW h−1), leading to reduced CO2 emissions. This study demonstrates the effective use of the Page model to optimize convective drying at 70 °C, reducing production costs by 47% and highlighting its potential to produce fiber-rich ingredients from BP with enhanced techno-functional and bioactive properties.

Effect of Ultrasound Conditions on Germination and Drying Characteristics of Bengal Gram (Cicer arietinum L.) and Determination of Physicochemical and Functional Properties of Flours

ABSTRACTThis study aims to investigate the effect of ultrasound conditions on the germination kinetics and drying characteristics of a germinated Bengal gram at different drying temperatures. Ultrasound treatment was given to the Bengal gram seeds at two different conditions, that is, before (US) and after soaking (SU), which was then followed by germination. This study also determines mass transfer parameters at drying temperatures of 45°C, 55°C, and 65°C and assesses the influence on the physicofunctional characteristics of a germinated Bengal gram. The germination rate behavior was effectively predicted using a zero‐order kinetic model with the highest R2 value of 0.7974–0.8857 in each nontreated (S) and treated (SU, US) Bengal gram seed, respectively. This study showed that the ultrasound treatment effectively enhanced the germination rate in both conditions, and the highest germination rate was found in pretreated ultrasound Bengal gram samples. The logarithmic thin layer drying model, with the highest average R2 of 0.9954 and the lowest average RMSE value of 0.0160, is the best‐fitted model to predict the changes in moisture ratio in both treated and nontreated conditions. The moisture diffusivity values at drying temperatures ranging from 45°C to 65°C were found in treated (US, SU) and nontreated (S) germinated samples ranging from 3.34 × 10−8 to 4.03 × 10−8 m2/s, 1.30 × 10−8 to 2.01 × 10−8 m2/s, and 6.6 × 10−9 to 8.06 × 10−9 m2/s, respectively. The protein content increased in the ultrasound‐treated sample between 12.37% and 13.50%. The solubility ranged from 8% to 10.36% throughout the treated and nontreated germinated Bengal gram flour. This study provides a unified approach to utilizing ultrasound‐treated germinated Bengal gram seeds as an alternative option to develop a functional product with better nutritional and functional properties.

Effects of aggregates and fibers on the strength and permeability of concrete exposed to low vacuum environment

The performance and regulation of concrete in low vacuum environments are receiving increasing attention. This study investigates the effects of aggregates and fibers on the strength and permeability of concrete in a low vacuum environment, using varying gradients of sand ratios (37.5 %, 40 %, and 42 %) and aggregate-to-binder ratios (3.27, 3.92, and 4.14). Three types of non-metallic fibers are utilized: polyethylene (PE), polyvinyl alcohol (PVA), and glass fibers. Evaluations focus on concrete strength, mass loss, gas permeability, capillary water absorption, and porosity. Results indicate that higher sand and aggregate-to-binder ratios enhance both flexural and compressive strength. Fiber incorporation improves flexural and compressive toughness, with PE fibers showing the most significant toughening effect. The low vacuum environment increases the strength of the concrete but reduces its axial compression toughness ratio and increases brittleness, while fiber incorporation helps improve the compression toughness of the concrete. Higher sand and aggregate-to-binder ratios reduce mass loss and accelerate drying equilibrium, while fibers increase mass loss and prolong drying equilibrium, with PVA fibers causing greater mass loss. The pattern of concrete mass loss can be explained by the tortuosity of the moisture diffusion path. Additionally, low vacuum significantly increases the gas permeability of concrete. Enhancing the sand and aggregate-to-binder ratios reduces permeability both before and after low vacuum treatment. Although fibers increase the gas permeability, they help mitigate this increase under low vacuum condition. Capillary water absorption tests reveal that concrete under low vacuum condition has a significantly higher water absorption rate compared to air-drying condition. Increasing sand and aggregate-to-binder ratios reduces water absorption and capillary water content, whereas fibers have the opposite effect. Porosity tests show that moisture migration in a low vacuum environment is mainly related to permeable porosity, while total porosity is more closely related to compressive strength.