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Keywords = air-conditioning absorption

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22 pages, 1916 KiB  
Article
Freeze-Dried Probiotic Fermented Camel Milk Enriched with Ajwa Date Pulp: Evaluation of Functional Properties, Probiotic Viability, and In Vitro Antidiabetic and Anticancer Activities
by Sally S. Sakr and Hassan Barakat
Foods 2025, 14(15), 2698; https://doi.org/10.3390/foods14152698 - 31 Jul 2025
Viewed by 306
Abstract
Noncommunicable diseases (NCDs) like diabetes and cancer drive demand for therapeutic functional foods. This study developed freeze-dried fermented camel milk (FCM) with Ajwa date pulp (ADP), evaluating its physical and functional properties, probiotic survival, and potential benefits for diabetes and cancer. To achieve [...] Read more.
Noncommunicable diseases (NCDs) like diabetes and cancer drive demand for therapeutic functional foods. This study developed freeze-dried fermented camel milk (FCM) with Ajwa date pulp (ADP), evaluating its physical and functional properties, probiotic survival, and potential benefits for diabetes and cancer. To achieve this target, six FCM formulations were prepared using ABT-5 starter culture (containing Lactobacillus acidophilus, Bifidobacterium bifidum, and Streptococcus thermophilus) with or without Lacticaseibacillus rhamnosus B-1937 and ADP (12% or 15%). The samples were freeze-dried, and their functional properties, such as water activity, dispersibility, water absorption capacity, water absorption index, water solubility index, insolubility index, and sedimentation, were assessed. Reconstitution properties such as density, flowability, air content, porosity, loose bulk density, packed bulk density, particle density, carrier index, Hausner ratio, porosity, and density were examined. In addition, color and probiotic survivability under simulated gastrointestinal conditions were analyzed. Also, antidiabetic potential was assessed via α-amylase and α-glucosidase inhibition assays, while cytotoxicity was evaluated using the MTT assay on Caco-2 cells. The results show that ADP supplementation significantly improved dispersibility (up to 72.73% in FCM15D+L). These improvements are attributed to changes in particle size distribution and increased carbohydrate and mineral content, which facilitate powder rehydration and reduce clumping. All FCM variants demonstrated low water activity (0.196–0.226), indicating good potential for shelf stability. The reconstitution properties revealed that FCM powders with ADP had higher bulk and packed densities but lower particle density and porosity than controls. Including ADP reduced interstitial air and increased occluded air within the powders, which may minimize oxidation risks and improve packaging efficiency. ADP incorporation resulted in a significant decrease in lightness (L*) and increases in redness (a*) and yellowness (b*), with greater pigment and phenolic content at higher ADP levels. These changes reflect the natural colorants and browning reactions associated with ADP, leading to a more intense and visually distinct product. Probiotic survivability was higher in ADP-fortified samples, with L. acidophilus and B. bifidum showing resilience in intestinal conditions. The FCM15D+L formulation exhibited potent antidiabetic effects, with IC50 values of 111.43 μg mL−1 for α-amylase and 77.21 μg mL−1 for α-glucosidase activities, though lower than control FCM (8.37 and 10.74 μg mL−1, respectively). Cytotoxicity against Caco-2 cells was most potent in non-ADP samples (IC50: 82.22 μg mL−1 for FCM), suggesting ADP and L. rhamnosus may reduce antiproliferative effects due to proteolytic activity. In conclusion, the study demonstrates that ADP-enriched FCM is a promising functional food with enhanced probiotic viability, antidiabetic potential, and desirable physical properties. This work highlights the potential of camel milk and date synergies in combating some NCDs in vitro, suggesting potential for functional food application. Full article
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35 pages, 2895 KiB  
Review
Ventilated Facades for Low-Carbon Buildings: A Review
by Pinar Mert Cuce and Erdem Cuce
Processes 2025, 13(7), 2275; https://doi.org/10.3390/pr13072275 - 17 Jul 2025
Viewed by 643
Abstract
The construction sector presently consumes about 40% of global energy and generates 36% of CO2 emissions, making facade retrofits a priority for decarbonising buildings. This review clarifies how ventilated facades (VFs), wall assemblies that interpose a ventilated air cavity between outer cladding [...] Read more.
The construction sector presently consumes about 40% of global energy and generates 36% of CO2 emissions, making facade retrofits a priority for decarbonising buildings. This review clarifies how ventilated facades (VFs), wall assemblies that interpose a ventilated air cavity between outer cladding and the insulated structure, address that challenge. First, the paper categorises VFs by structural configuration, ventilation strategy and functional control into four principal families: double-skin, rainscreen, hybrid/adaptive and active–passive systems, with further extensions such as BIPV, PCM and green-wall integrations that couple energy generation or storage with envelope performance. Heat-transfer analysis shows that the cavity interrupts conductive paths, promotes buoyancy- or wind-driven convection, and curtails radiative exchange. Key design parameters, including cavity depth, vent-area ratio, airflow velocity and surface emissivity, govern this balance, while hybrid ventilation offers the most excellent peak-load mitigation with modest energy input. A synthesis of simulation and field studies indicates that properly detailed VFs reduce envelope cooling loads by 20–55% across diverse climates and cut winter heating demand by 10–20% when vents are seasonally managed or coupled with heat-recovery devices. These thermal benefits translate into steadier interior surface temperatures, lower radiant asymmetry and fewer drafts, thereby expanding the hours occupants remain within comfort bands without mechanical conditioning. Climate-responsive guidance emerges in tropical and arid regions, favouring highly ventilated, low-absorptance cladding; temperate and continental zones gain from adaptive vents, movable insulation or PCM layers; multi-skin adaptive facades promise balanced year-round savings by re-configuring in real time. Overall, the review demonstrates that VFs constitute a versatile, passive-plus platform for low-carbon buildings, simultaneously enhancing energy efficiency, durability and indoor comfort. Future advances in smart controls, bio-based materials and integrated energy-recovery systems are poised to unlock further performance gains and accelerate the sector’s transition to net-zero. Emerging multifunctional materials such as phase-change composites, nanostructured coatings, and perovskite-integrated systems also show promise in enhancing facade adaptability and energy responsiveness. Full article
(This article belongs to the Special Issue Sustainable Development of Energy and Environment in Buildings)
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16 pages, 4297 KiB  
Article
The Influence of Absorber Properties on Operating Parameters and Electricity Generation in the Solar Chimney with a Vertical Collector
by Sylwia Berdowska
Energies 2025, 18(14), 3740; https://doi.org/10.3390/en18143740 - 15 Jul 2025
Viewed by 237
Abstract
The paper presents an analysis of the operating parameters of a solar chimney with a non-selective and selective absorbers. The analyzed system consisted of a rectangular vertical collector integrated with a chimney. The collector surface was 30 m2, while the installation [...] Read more.
The paper presents an analysis of the operating parameters of a solar chimney with a non-selective and selective absorbers. The analyzed system consisted of a rectangular vertical collector integrated with a chimney. The collector surface was 30 m2, while the installation was 80 m high. The calculations were performed for the climatic conditions in Katowice, Poland. The work included an analysis of parameters such as air temperature increase and its velocity and mass flow in the solar chimney system. The cumulative amounts of electricity that can be obtained in each month of the year were shown. A comparison of electricity generation in the installation with an absorber covered with a non-selective coating and selective coatings was made. The installation with an absorber with an absorption coefficient of 0.95 and an emission coefficient of 0.05 allowed for the generation of the largest amount of electricity during the year. Full article
(This article belongs to the Section A2: Solar Energy and Photovoltaic Systems)
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23 pages, 4306 KiB  
Article
A Dynamic Investigation of a Solar Absorption Plant with Nanofluids for Air-Conditioning of an Office Building in a Mild Climate Zone
by Luca Cirillo, Sabrina Gargiulo, Adriana Greco, Claudia Masselli, Sergio Nardini, Vincenzo Orabona and Lucrezia Verneau
Energies 2025, 18(13), 3480; https://doi.org/10.3390/en18133480 - 1 Jul 2025
Viewed by 325
Abstract
This study explores the impact of using water-Al2O3 nanofluids, at different nanoparticle concentrations, in solar thermal collectors for solar cooling applications. Improving the seasonal energy performance of solar cooling systems is a current research priority, and this work investigates whether [...] Read more.
This study explores the impact of using water-Al2O3 nanofluids, at different nanoparticle concentrations, in solar thermal collectors for solar cooling applications. Improving the seasonal energy performance of solar cooling systems is a current research priority, and this work investigates whether nanofluids can significantly enhance system efficiency compared to traditional heat transfer fluids. A transient simulation was carried out using a dynamic model developed in TRNSYS (TRANsient SYstem Simulation), evaluating the system performance throughout the cooling season. The results show that in July, under low volumetric flow conditions and with nanoparticle concentrations of 0.6% and 0.3%, the solar fraction reaches a maximum value of 1. Using a nanofluid at 0.6% concentration leads to significantly higher fractional energy savings compared to pure water. Despite increased pumping energy, the overall energy savings—which include the contribution from an auxiliary boiler—exceed 80% when nanofluids are used. This study goes beyond previous work by providing a dynamic, system-level simulation of nanofluid-enhanced solar cooling performance under realistic operating conditions. The findings demonstrate the practical potential of nanofluids as a valid and more energy-efficient alternative in solar thermal applications. Full article
(This article belongs to the Special Issue Advanced Thermal Simulation of Energy Systems: 2nd Edition)
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14 pages, 1694 KiB  
Article
An Assessment of Anion Exchange Membranes for CO2 Capture Processes: A Focus on Fumasep® and Sustainion®
by Kseniya Papchenko, Sandra Kentish and Maria Grazia De Angelis
Polymers 2025, 17(11), 1581; https://doi.org/10.3390/polym17111581 - 5 Jun 2025
Viewed by 864
Abstract
Anion exchange membranes are utilised in cutting-edge energy technologies including electrolysers and fuel cells. Recently, these membranes have also emerged as a promising tool in CO2 capture techniques, such as moisture-driven direct air capture and the separation of CO2 from other [...] Read more.
Anion exchange membranes are utilised in cutting-edge energy technologies including electrolysers and fuel cells. Recently, these membranes have also emerged as a promising tool in CO2 capture techniques, such as moisture-driven direct air capture and the separation of CO2 from other gases, leveraging the moisture-induced sorption/desorption and diffusion of CO2 in its ionic forms. In this study, we examine the absorption and permeation of CO2 and CH4 in two commercially available anion exchange membranes, Fumasep® and Sustainion®, under dry conditions. With the exception of CO2 sorption in Fumasep®, these measurements have not been previously reported. These new data points are crucial for evaluating the fundamental separation capabilities of these materials and for devising innovative CO2 capture strategies, as well as for the simulation of novel combined processes. In a dry state, both materials demonstrate similar CO2 absorption levels, with a higher value for Sustainion®. The CO2 solubility coefficient decreases with pressure, as is typical for glassy polymers. Fumasep® exhibits higher CO2/CH4 ideal solubility selectivity, equal to ~10 at sub-ambient pressures, and higher diffusivity. The CO2 diffusion coefficient increases with the CO2 concentration in both membranes due to swelling of the matrix, varying between 0.7 and 2.2 × 10−8 cm2/s for Fumasep® and between 1.6 and 9.0 × 10−9 cm2/s for Sustainion®. CO2 permeability exhibits a minimum at a pressure of approximately 2–3 bar. The CO2 permeability in the dry state is higher in Fumasep® than in Sustainion®: 3.43 and 0.72 Barrer at a 2-bar transmembrane pressure, respectively. The estimated perm-selectivity was found to reach values of up to 40 at sub-ambient pressures. The CO2 permeability and CO2/CH4 estimated perm-selectivity in both polymers are of a similar order of magnitude to those measured in fluorinated ion exchange membranes such as Nafion®. Full article
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20 pages, 2486 KiB  
Article
An Experimental Study on the Novel Ozone-Electro-Fenton Coupled Reactor for Treating Ofloxacin-Containing Industrial Wastewater
by Yifeng Han, Lifen Zhang, Keyan Liu, Jinliang Tao and Feng Wei
Water 2025, 17(11), 1649; https://doi.org/10.3390/w17111649 - 29 May 2025
Viewed by 457
Abstract
Industrial organic wastewater, with its complex composition, high biological toxicity, and recalcitrance, has become a major challenge in water pollution control. This is especially true for antibiotic-containing wastewater, such as ofloxacin wastewater, for which there is an urgent need to develop effective treatment [...] Read more.
Industrial organic wastewater, with its complex composition, high biological toxicity, and recalcitrance, has become a major challenge in water pollution control. This is especially true for antibiotic-containing wastewater, such as ofloxacin wastewater, for which there is an urgent need to develop effective treatment technologies. Conventional treatment processes are insufficiently efficient, while individual advanced oxidation processes (AOPs) have drawbacks such as poor oxidation selectivity and catalyst deactivation. To address these issues, researchers have explored the coupling of different AOPs and found that such combinations can enhance the oxidation performance, achieve complementary advantages, reduce the equipment costs, and offer great development potential. An experiment was conducted to evaluate the performance of an Ozone-Electro-Fenton coupled process in treating ofloxacin industrial wastewater. The results demonstrated that under the same conditions, after four hours of treatment, the coupled process achieved a 70% reduction in the UV absorption peak of the wastewater, compared to less than 20% for individual processes, indicating a significant synergistic effect. Further optimization of the ozone aeration structure revealed that with a hole size of 0.5 mm, single-layer aeration holes, and six holes, the COD removal rate reached 96% after six hours, the ozone utilization improved to 85%, and the gas holdup stabilized at 4.6%. Under these conditions, the mixture of ozone and air bubbles formed mixed bubbles. Influenced by the electric field and electrode plate wall effects, the bubble residence time was prolonged. The bubble size was approximately 2.8 mm, the gas flow horizontal velocity was about 18.5 m/s, and after a horizontal displacement of 0.17 mm in the wastewater, the lateral velocity became zero. The ratio of the distance between the bubble center and the wall to the equivalent bubble diameter was approximately 3.45. The bubbles were subject to a strong wall effect, which extended their residence time. This not only facilitated the removal of small bubbles from the electrode plates but also enhanced the ion diffusion near the plates, thereby boosting pollutant degradation. This study shows that the Ozone-Electro-Fenton coupled process is highly effective in degrading ofloxacin industrial wastewater, offering an innovative solution for treating other antibiotic-containing wastewater. Future research will focus on further optimizing the process, improving its adaptability to complex matrix wastewater, and validating it at the pilot scale to promote its engineering application. Full article
(This article belongs to the Section Wastewater Treatment and Reuse)
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14 pages, 957 KiB  
Article
Fat Reduction in Peruvian Carrot (Arracacia xanthorrhiza) Snacks: Effectiveness of Edible Coatings and Optimization of Frying Conditions
by Viviane de Souza Silva, Luna Valentina Angulo Arias, José Ignacio Velasco, Farayde Matta Fakhouri and Rafael Augustus de Oliveira
Foods 2025, 14(11), 1895; https://doi.org/10.3390/foods14111895 - 26 May 2025
Viewed by 460
Abstract
Peruvian carrot is a root with a pleasant taste but a short shelf life. Developing Peruvian carrot snacks with appealing sensory characteristics, a crunchy texture, and reduced lipid content aligns with modern consumer demands and represents an innovative approach to food diversification. To [...] Read more.
Peruvian carrot is a root with a pleasant taste but a short shelf life. Developing Peruvian carrot snacks with appealing sensory characteristics, a crunchy texture, and reduced lipid content aligns with modern consumer demands and represents an innovative approach to food diversification. To ensure product quality, snacks must have a low water content to prevent microbial growth and maintain crispness. Therefore, optimizing process variables through pre-treatments is essential to achieving the desired characteristics. This study aimed to evaluate the influence of frying conditions on the water content, lipid absorption, and sensory acceptance of Peruvian carrot snacks. The preparation process involved sanitizing and slicing the roots, air-drying them at room temperature, and frying them according to an experimental design. The optimal frying conditions were 160 °C for 18 s and 174 °C for 30 s. Three different treatments were tested: two with edible coatings made from Peruvian carrot starch at concentrations of 3:20 and 5:10 (starch %/glycerol %) and one control sample without a coating. Sensory evaluation showed significant differences between coated and uncoated snacks, with all samples receiving high consumer acceptance. Notably, coated snacks exhibited a 50% reduction in lipid absorption compared to the control while also retaining a lower water content, key factors in maintaining texture, preserving quality, and extending shelf life. Furthermore, the application of edible coatings proved effective in reducing the caloric content of the snacks, making them a healthier alternative. Full article
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18 pages, 8119 KiB  
Article
Study on the Photosynthetic Physiological Responses of Greenhouse Young Chinese Cabbage (Brassica rapa L. Chinensis Group) Affected by Particulate Matter Based on Hyperspectral Analysis
by Lijuan Kong, Siyao Gao, Jianlei Qiao, Lina Zhou, Shuang Liu, Yue Yu and Haiye Yu
Plants 2025, 14(10), 1479; https://doi.org/10.3390/plants14101479 - 15 May 2025
Viewed by 522
Abstract
Particulate matter affects both the light environment and air quality in greenhouses, obstructing normal gas exchange and hindering efficient physiological activities such as photosynthesis. This study focused on young Chinese cabbage (Brassica rapa L. Chinensis Group) in a greenhouse at harvest [...] Read more.
Particulate matter affects both the light environment and air quality in greenhouses, obstructing normal gas exchange and hindering efficient physiological activities such as photosynthesis. This study focused on young Chinese cabbage (Brassica rapa L. Chinensis Group) in a greenhouse at harvest time, monitoring and comparing hyperspectral information, net photosynthetic rate, and microscopic leaf structure under two conditions: a quantitative artificial particulate matter environment and a healthy environment. Based on microscopic results combined with spectral responses and changes in photosynthetic physiological information, it is believed that particulate matter enters plant cells through stomata. Through retention and transport pathways, it disrupts the membrane structure, organelles, and other components of plant cells, resulting in adverse effects on the plant’s physiological functions. The study analyzed the mechanisms by which particulate matter influences the photosynthesis, spectral characteristics, and physiological responses of young Chinese cabbage. Physiological Reflectance Index (PRI), Modified Chlorophyll Absorption Ratio Index (MCARI), spectral red-edge position (λr), and spectral sensitive bands were used as spectral feature variables. Through cubic polynomial and 24 combinations of spectral preprocessing and modeling methods, an inversion model of spectral features and net photosynthetic rate was established. The optimal combination of spectral preprocessing and modeling methods was finally selected as SG + SD + PLS + MSC, which consists of Savitzky-Golay smooth (SG), second derivative (SD), partial least squares (PLS), and multiplicative scatter correction (MSC). The coefficient of determination (R2) of the model is 0.9513. The results indicate that particulate matter affects plant photosynthesis. The SG + SD + PLS + MSC combination method is relatively advantageous for processing the photosynthetic spectral physiological information of plants under the influence of particulate matter. The results of this study will deepen the understanding of the mechanisms by which particulate matter affects plants and provide a reference for the physiological information inversion of greenhouse vegetables under particulate matter pollution. Full article
(This article belongs to the Section Plant Modeling)
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13 pages, 2363 KiB  
Article
Spectroscopic Quantification of Metallic Element Concentrations in Liquid-Propellant Rocket Exhaust Plumes
by Siyang Tan, Song Yan, Xiang Li, Tong Su, Qingchun Lei and Wei Fan
Aerospace 2025, 12(5), 427; https://doi.org/10.3390/aerospace12050427 - 11 May 2025
Viewed by 441
Abstract
Accurate quantification of metallic contaminants in rocket exhaust plumes serves as a critical diagnostic indicator for engine wear monitoring. This paper develops a hybrid method combining atomic emission spectroscopy (AES) theory with a genetic algorithm (GA) optimized backpropagation (BP) network to quantify the [...] Read more.
Accurate quantification of metallic contaminants in rocket exhaust plumes serves as a critical diagnostic indicator for engine wear monitoring. This paper develops a hybrid method combining atomic emission spectroscopy (AES) theory with a genetic algorithm (GA) optimized backpropagation (BP) network to quantify the metallic element concentrations in liquid-propellant rocket exhaust plumes. The proposed method establishes linearized intensity–concentration mapping through the introduction of a photon transmission factor, which is derived from radiative transfer theory and experimentally calibrated via AES measurement. This critical innovation decouples the inherent nonlinearities arising from self-absorption artifacts. Through the use of the transmission factor, the training dataset for the BP network is systematically constructed by performing spectral simulations of atomic emissions. Finally, the trained network is employed to predict the concentration of metallic elements from the measured atomic emission spectra. These spectra are generated by introducing a solution containing metallic elements into a CH4-air premixed jet flame. The predictive accuracy of the method is rigorously evaluated through 32 independent experimental trials. Results show that the quantification error of metallic elements remains within 6%, and the method exhibits robust performance under conditions of spectral self-absorption, demonstrating its reliability for rocket engine health monitoring applications. Full article
(This article belongs to the Section Astronautics & Space Science)
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14 pages, 3746 KiB  
Article
Scalable Synthesis of PtAu Nanoalloy-Decorated Hydrogenated TiO2 for High-Efficiency Indoor Formaldehyde Photodegradation
by Hairui Cai, Benjamin Yang, Jie Hou, Ziqi Wang and Zhuo Li
Nanomaterials 2025, 15(9), 683; https://doi.org/10.3390/nano15090683 - 30 Apr 2025
Viewed by 440
Abstract
Formaldehyde, a pervasive indoor air pollutant posing significant health risks, has driven extensive research into advanced mitigation strategies to ensure safer living environments. Herein, this study presents a synthesis method for the large-scale production of hydrogenated TiO2 (P25) loaded with PtAu nanoalloys [...] Read more.
Formaldehyde, a pervasive indoor air pollutant posing significant health risks, has driven extensive research into advanced mitigation strategies to ensure safer living environments. Herein, this study presents a synthesis method for the large-scale production of hydrogenated TiO2 (P25) loaded with PtAu nanoalloys (P25(H)-PtAu), using a combination of ball milling and high-temperature annealing. Hydrogenation-induced defect-rich TiO2 efficiently improves visible light absorption, enhancing the utilization of visible light in photocatalytic reactions. Mechanochemical ball milling was employed to prepare ultrasmall PtAu nanoalloys with a size of 3.7 ± 0.1 nm, which were uniformly dispersed on the surface of P25(H). Density functional theory (DFT) results indicate that PtAu nanoalloys synergistically enhance charge separation via Schottky junctions and surface reaction kinetics by optimizing reactant adsorption. As a result, P25(H)-PtAu achieves industrially relevant formaldehyde removal efficiency (97.8%) under ambient light conditions while maintaining scalability (10 g batches). This work provides a scalable framework for developing manufacturable photocatalysts, with immediate applications in heating, ventilation and air conditioning systems, and air purifiers. Full article
(This article belongs to the Section Energy and Catalysis)
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15 pages, 9956 KiB  
Article
Improvement of Sound-Absorbing Dips in Nonwoven Fabric Sheet with Back Air Space: Division of Back Air Space by Additional Nonwoven Fabric Sheet
by Shuichi Sakamoto, Kodai Sato, Gaku Muroi, Yusuke Nakao, Kaito Kuboki and Nobuhito Taguchi
Acoustics 2025, 7(2), 25; https://doi.org/10.3390/acoustics7020025 - 30 Apr 2025
Viewed by 995
Abstract
This study was conducted to improve the sound absorption dips in nonwoven fabric sheets with a back air space. Considering the particle velocity distribution in the back air space, another nonwoven sheet was added to divide the air space into layers. The sound [...] Read more.
This study was conducted to improve the sound absorption dips in nonwoven fabric sheets with a back air space. Considering the particle velocity distribution in the back air space, another nonwoven sheet was added to divide the air space into layers. The sound absorption coefficient of the sound-absorbing structure was theoretically derived using the transfer matrix method. The nonwoven sheet model with the Rayleigh model and the air space behind the nonwoven sheet were mathematically represented using the transfer matrix. The transfer function method was employed to combine the transfer matrices to obtain the sound absorption coefficient. A two-microphone acoustic impedance tube was used to measure the sound absorption coefficient, and the theoretical and experimental values were compared. The sound absorption dip of the first order was improved by placing a nonwoven sheet at a position half the thickness of the back air space. It was theoretically predicted that placing the nonwoven sheet at 1/4 of the back air space thickness from the rigid wall would improve the first- and second-order sound absorption dips. By selecting the conditions, a similar trend was observed during the experiments. The study shows that the higher the ventilation resistance of the added nonwoven fabric sheet, the more improved the sound absorption dip. Full article
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15 pages, 3815 KiB  
Article
Study of Bacterial Elution from High-Efficiency Glass Fiber Filters
by Le Rong, Yun Liang, Zhaoqian Li, Desheng Wang, Hao Wang, Lingyun Wang and Min Tang
Separations 2025, 12(5), 110; https://doi.org/10.3390/separations12050110 - 25 Apr 2025
Viewed by 443
Abstract
Antibacterial filter materials have been effectively utilized for controlling biological contaminants and purifying indoor air, with the market for such materials experiencing continuous expansion. Currently, textile antibacterial testing standards are widely adopted to evaluate the antimicrobial efficacy of filter materials, yet no dedicated [...] Read more.
Antibacterial filter materials have been effectively utilized for controlling biological contaminants and purifying indoor air, with the market for such materials experiencing continuous expansion. Currently, textile antibacterial testing standards are widely adopted to evaluate the antimicrobial efficacy of filter materials, yet no dedicated assessment protocols specifically tailored for filtration media have been established. This study aims to investigate the applicability of textile antibacterial testing methods to high-efficiency glass fiber filter materials (filtration efficiency > 99.9%), as well as to explore the factors that affect the rate of bacterial elution from high-efficiency glass fiber filter materials. By referencing the textile antibacterial testing standard (absorption method), significant discrepancies in bacterial recovery counts were observed between the high-efficiency glass fiber materials and the various textile control samples, with the former exhibiting a markedly lower recovery rate (approximately 10%). Pore structure and wettability analyses revealed the underlying causes of these differences. To ensure the accuracy of the antibacterial evaluation results, the effects of oscillation elution parameters (time and intensity) and material incubation conditions (duration, sealing and humidity) on bacterial recovery rates in glass fiber filter materials were systematically investigated to optimize the elution methodology. The results indicate that specimen type, size, elution method, incubation duration (4 h or 24 h), sealing conditions, and environmental humidity (10% or 30%, 60% and 95% RH) collectively influence bacterial recovery efficiency. The highest recovery efficiency (55%) was achieved when the filter materials were incubated in a sealed environment with humidity maintained at ≥60% RH. These findings emphasize the critical need to establish clear and specialized antibacterial performance testing standards for filter materials. The study provides essential guidance for developing material-specific evaluation protocols to ensure a reliable and standardized assessment of antimicrobial efficacy in high-efficiency filtration systems. Full article
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26 pages, 15094 KiB  
Article
Design and Analysis of a Novel Hydraulic Energy Storage Component
by Jinlin Yao, Xiangyu He, Yuanhao Yang, Yanshuo Zhu, Guangxin Xiao and Yizhe Huang
Machines 2025, 13(4), 325; https://doi.org/10.3390/machines13040325 - 17 Apr 2025
Viewed by 447
Abstract
The hydraulic energy storage component (HESC) is the core component of hydraulic energy regeneration (HER) technologies in construction equipment, directly influencing the overall energy efficiency of the system. However, under complex practical operating conditions, the performance of traditional HESCs has become a critical [...] Read more.
The hydraulic energy storage component (HESC) is the core component of hydraulic energy regeneration (HER) technologies in construction equipment, directly influencing the overall energy efficiency of the system. However, under complex practical operating conditions, the performance of traditional HESCs has become a critical factor limiting the broader application of HER technologies. This paper proposes a novel hydraulic energy storage component (NHESC) that integrates hybrid energy storage through the use of compressed air and electric energy. The system configuration of the NHESC is first designed, followed by the modeling of key components and analysis of working states. Second, based on the working state of energy absorption and release in the NHESC, a corresponding determination strategy is formulated. Third, a simulation model of the boom potential energy regeneration (PER) system based on the NHESC is developed, with partial experimental validation to verify its reliability. Finally, the recovery, reuse, and regeneration efficiencies in state pair B-E of the NHESC mode and the accumulator mode are compared, followed by an analysis of energy losses in the hydraulic components. The analysis results, based on simulation, indicate that the regeneration efficiency of the NHESC is 55.1%, which is better than the 41.1% of the traditional hydraulic accumulator. The NHESC combines the advantages of compressed gas energy storage and electric energy storage, effectively resolving issues of passive operation and uncontrollability while demonstrating superior energy regeneration capabilities. Full article
(This article belongs to the Section Machine Design and Theory)
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20 pages, 6520 KiB  
Article
Effect of Gravel Size, Microwave Irradiation (1 to 2.5 min), Moisture, and Quenching on Aggregate Properties of Chert Gravel: Valorizing a “Waste” Byproduct of Sand Quarrying
by Mark Tzibulsky and Vladimir Frid
Clean Technol. 2025, 7(2), 29; https://doi.org/10.3390/cleantechnol7020029 - 3 Apr 2025
Viewed by 2263
Abstract
Chert gravel, a byproduct of sand quarrying, remains an underutilized material in construction due to its low microwave (MW) absorption and high mechanical strength. The present study deals with the potential of MW irradiation as a novel, energy-efficient method for processing chert gravel [...] Read more.
Chert gravel, a byproduct of sand quarrying, remains an underutilized material in construction due to its low microwave (MW) absorption and high mechanical strength. The present study deals with the potential of MW irradiation as a novel, energy-efficient method for processing chert gravel into high-quality aggregates, reducing reliance on virgin materials. The research systematically examines MW exposure duration (1–2.5 min), rock size (150–800 g), moisture conditions, and cooling methods (air vs. water quenching) to optimize fragmentation. Experimental results indicate that larger rock sizes (600–800 g) yield coarser, less uniform aggregates, while prolonged MW exposure (>2 min) induces extensive micro-fracturing, producing finer, well-graded particles. Water quenching significantly intensifies fragmentation, generating irregular but highly fragmented aggregates, whereas pre-wetted samples exhibit finer and more uniform breakage than dry samples. The findings introduce a novel approach for optimizing chert gravel fragmentation, a material previously considered unsuitable for MW treatment. The study proposed a customizable methodology for tailoring aggregate properties through precise control of MW parameters, offering a sustainable alternative to conventional crushing. The results contribute to resource conservation, reduced energy consumption, and climate change mitigation, paving the way for more sustainable construction practices. Full article
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20 pages, 2543 KiB  
Article
Effects of Different Drying Methods on Physicochemical Properties and Nutritional Quality of Abalone Bioactive Peptides
by Qiting Li, Longxiang Li, Pufu Lai, Yingying Wei, Chunmei Lai, Yusha Liu, Mengjie Yang, Shaoxiong Zhou, Junchen Chen and Junzheng Sun
Molecules 2025, 30(7), 1516; https://doi.org/10.3390/molecules30071516 - 28 Mar 2025
Cited by 2 | Viewed by 834
Abstract
This study conducted a systematic comparison of four drying methods (vacuum freeze-drying, spray drying, spray freeze-drying, and hot air drying) on abalone bioactive peptides, investigating their effects on physicochemical properties and nutritional composition. Scanning electron microscopy revealed distinct morphological characteristics: hot-air-dried samples showed [...] Read more.
This study conducted a systematic comparison of four drying methods (vacuum freeze-drying, spray drying, spray freeze-drying, and hot air drying) on abalone bioactive peptides, investigating their effects on physicochemical properties and nutritional composition. Scanning electron microscopy revealed distinct morphological characteristics: hot-air-dried samples showed compact structures with large particles, and vacuum-freeze-dried samples exhibited flaky morphology, while spray-freeze-dried and spray-dried samples demonstrated advantageous smaller particle sizes. Spray freeze-drying achieved superior emulsification capacity and fat absorption, significantly higher than hot air drying. The enhanced performance was attributed to increased exposure of hydrophobic amino acid residues and improved surface activity. Regarding nutritional composition, vacuum freeze-drying demonstrated optimal protein and total amino acid preservation, while spray freeze-drying showed the highest retention of Ca and Fe. Interestingly, hot air drying exhibited superior vitamin A retention, attributed to its fat-soluble nature and stability below 100 °C. The particle size reduction in spray-freeze-dried samples enhanced solvent–solute contact area, contributing to improved solubility and consequently superior foaming properties. These findings provide valuable insights into the relationship between drying methods and product characteristics, offering guidance for optimizing processing conditions in marine protein production. Full article
(This article belongs to the Section Food Chemistry)
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