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Search Results (1,361)

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20 pages, 2267 KiB  
Article
Alterations in the Platelet Transcriptome Mediate Prenatal Thirdhand Smoke Exposure Associated Thrombogenicity via Integrated miRNA-mRNA Regulatory Networks
by Hamdy E. A. Ali, Ahmed B. Alarabi, Fatima Z. Alshbool and Fadi T. Khasawneh
Int. J. Mol. Sci. 2025, 26(15), 7633; https://doi.org/10.3390/ijms26157633 - 7 Aug 2025
Abstract
Cigarette smoking is acknowledged as the most preventable risk factor for thrombogenesis-associated cardiovascular disease. Mice prenatally exposed to the thirdhand smoke (THS) form of tobacco exhibited a higher tendency to develop occlusive thrombosis, along with enhancement of several platelet functional responses. Our objective [...] Read more.
Cigarette smoking is acknowledged as the most preventable risk factor for thrombogenesis-associated cardiovascular disease. Mice prenatally exposed to the thirdhand smoke (THS) form of tobacco exhibited a higher tendency to develop occlusive thrombosis, along with enhancement of several platelet functional responses. Our objective was to investigate whether prenatal (in utero) THS exposure impacts the platelet transcriptome, resulting in enhanced platelet functional responses, thereby underlying THS-associated thrombogenicity. Blood samples obtained from twenty male mice prenatally exposed to THS, along with an equal number of age-matched male mice exposed to clean air (CA) as a control, were divided into pools of five animals and used to prepare leukocyte and red blood cell-depleted platelets. RNA sequencing for mRNA and microRNA (miRNA) was utilized to analyze and compare the platelet expression profiles of the two exposure groups. RNA seq analyses revealed distinct changes in both gene expression and miRNA profiles, with 448 coding genes and 18 miRNAs significantly altered between the two groups. miRNA–mRNA interaction analysis highlighted 14 differentially expressed miRNAs that potentially target 120 of the differentially expressed genes in our data set. Interestingly, altered genes in miRNA–mRNA pairs were functionally enriched into pathways associated with platelet physiology, including platelet activation, signaling and aggregation, and cellular response to chemical stimuli. Our findings establish—for the first time—that prenatal exposure to THS modifies the platelet transcriptome, thereby rendering platelets hypersensitive to stimuli and more prone to thrombogenicity. Additionally, we illuminate the coordinated function of platelet miRNA and mRNA targets in mediating this response. Full article
(This article belongs to the Special Issue MicroRNAs and mRNA in Human Health and Disease)
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23 pages, 3831 KiB  
Article
Estimating Planetary Boundary Layer Height over Central Amazonia Using Random Forest
by Paulo Renato P. Silva, Rayonil G. Carneiro, Alison O. Moraes, Cleo Quaresma Dias-Junior and Gilberto Fisch
Atmosphere 2025, 16(8), 941; https://doi.org/10.3390/atmos16080941 - 5 Aug 2025
Abstract
This study investigates the use of a Random Forest (RF), an artificial intelligence (AI) model, to estimate the planetary boundary layer height (PBLH) over Central Amazonia from climatic elements data collected during the GoAmazon experiment, held in 2014 and 2015, as it is [...] Read more.
This study investigates the use of a Random Forest (RF), an artificial intelligence (AI) model, to estimate the planetary boundary layer height (PBLH) over Central Amazonia from climatic elements data collected during the GoAmazon experiment, held in 2014 and 2015, as it is a key metric for air quality, weather forecasting, and climate modeling. The novelty of this study lies in estimating PBLH using only surface-based meteorological observations. This approach is validated against remote sensing measurements (e.g., LIDAR, ceilometer, and wind profilers), which are seldom available in the Amazon region. The dataset includes various meteorological features, though substantial missing data for the latent heat flux (LE) and net radiation (Rn) measurements posed challenges. We addressed these gaps through different data-cleaning strategies, such as feature exclusion, row removal, and imputation techniques, assessing their impact on model performance using the Root Mean Square Error (RMSE), Mean Absolute Error (MAE), and r2 metrics. The best-performing strategy achieved an RMSE of 375.9 m. In addition to the RF model, we benchmarked its performance against Linear Regression, Support Vector Regression, LightGBM, XGBoost, and a Deep Neural Network. While all models showed moderate correlation with observed PBLH, the RF model outperformed all others with statistically significant differences confirmed by paired t-tests. SHAP (SHapley Additive exPlanations) values were used to enhance model interpretability, revealing hour of the day, air temperature, and relative humidity as the most influential predictors for PBLH, underscoring their critical role in atmospheric dynamics in Central Amazonia. Despite these optimizations, the model underestimates the PBLH values—by an average of 197 m, particularly in the spring and early summer austral seasons when atmospheric conditions are more variable. These findings emphasize the importance of robust data preprocessing and higtextight the potential of ML models for improving PBLH estimation in data-scarce tropical environments. Full article
(This article belongs to the Special Issue Applications of Artificial Intelligence in Atmospheric Sciences)
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15 pages, 630 KiB  
Article
Application of a Low-Cost Electronic Nose to Differentiate Between Soils Polluted by Standard and Biodegradable Hydraulic Oils
by Piotr Borowik, Przemysław Pluta, Miłosz Tkaczyk, Krzysztof Sztabkowski, Rafał Tarakowski and Tomasz Oszako
Chemosensors 2025, 13(8), 290; https://doi.org/10.3390/chemosensors13080290 - 5 Aug 2025
Abstract
Detection of soil pollution by petroleum products is necessary to remedy threats to economic and human health. Pollution by hydraulic oil often occurs through leaks from forestry machinery such as harvesters. Electronic noses equipped with gas sensor arrays are promising tools for applications [...] Read more.
Detection of soil pollution by petroleum products is necessary to remedy threats to economic and human health. Pollution by hydraulic oil often occurs through leaks from forestry machinery such as harvesters. Electronic noses equipped with gas sensor arrays are promising tools for applications of pollution detection and monitoring. A self-made, low-cost electronic nose was used for differentiation between clean and polluted samples, with two types of oils and three levels of pollution severity. An electronic nose uses the TGS series of gas sensors, manufactured by Figaro Inc. Sensor responses to changes in environmental conditions from clean air to measured odor, as well as responses to changes in sensor operation temperature, were used for analysis. Statistically significant response results allowed for the detection of pollution by biodegradable oil, while standard mineral oil was difficult to detect. It was demonstrated that the TGS 2602 gas sensor is most suitable for the studied application. LDA analysis demonstrated multidimensional data patterns allowing differentiation between sample categories and pollution severity levels. Full article
(This article belongs to the Special Issue Electronic Nose and Electronic Tongue for Substance Analysis)
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25 pages, 1165 KiB  
Article
China’s Low-Carbon City Pilot Policy, Eco-Efficiency, and Energy Consumption: Study Based on Period-by-Period PSM-DID Model
by Xiao Na Li and Hsing Hung Chen
Energies 2025, 18(15), 4126; https://doi.org/10.3390/en18154126 - 4 Aug 2025
Viewed by 218
Abstract
The sustainable development of Chinese cities is of long-term significance. Multiple environmental regulatory instruments aim to promote the parallel advancement of environmental conservation and economic growth. This study examines three batches of low-carbon city pilot (LCCP) programs, employing eco-efficiency as the outcome variable. [...] Read more.
The sustainable development of Chinese cities is of long-term significance. Multiple environmental regulatory instruments aim to promote the parallel advancement of environmental conservation and economic growth. This study examines three batches of low-carbon city pilot (LCCP) programs, employing eco-efficiency as the outcome variable. Using conventional difference-in-differences (DID) models, time-varying DID models, and period-by-period propensity score matching DID (PSM-DID) models with city and time fixed effects, we investigate the comprehensive impact of pilot policies on both economic and environmental performance. Eco-efficiency, measured through the Data Envelopment Analysis (DEA) model, exhibits a strong correlation with energy consumption patterns, as carbon emissions and air pollutants predominantly originate from non-clean energy utilization. The analysis reveals that LCCP policies significantly enhance eco-efficiency. These findings demonstrate robustness across placebo tests, endogeneity treatments, and alternative outcome variable specifications. The first and third LCCP batches significantly improve eco-efficiency, whereas the second batch demonstrates no statistically significant effect. Significant impacts emerge in regions where cities hold pilot status while provinces do not; conversely, regions where both cities and provinces participate in pilot programs show no significant effects. Finally, from an energy consumption perspective, policy recommendations are proposed to further enhance eco-efficiency through regulatory instruments. Full article
(This article belongs to the Special Issue Sustainable Energy Futures: Economic Policies and Market Trends)
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24 pages, 6757 KiB  
Article
Design and Testing of a Pneumatic Jujube Harvester
by Huaming Hou, Wei Niu, Qixian Wen, Hairui Yang, Jianming Zhang, Rui Zhang, Bing Xv and Qingliang Cui
Agronomy 2025, 15(8), 1881; https://doi.org/10.3390/agronomy15081881 - 3 Aug 2025
Viewed by 159
Abstract
Jujubes have a beautiful taste, and high nutritional and economic value. The planting area of dwarf and densely planted jujubes is large and shows an increasing trend; however, the mechanization level and efficiency of fresh jujube harvesting are low. For this reason, our [...] Read more.
Jujubes have a beautiful taste, and high nutritional and economic value. The planting area of dwarf and densely planted jujubes is large and shows an increasing trend; however, the mechanization level and efficiency of fresh jujube harvesting are low. For this reason, our research group conducted a study on mechanical harvesting technology for fresh jujubes. A pneumatic jujube harvester was designed. This harvester is composed of a self-regulating picking mechanism, a telescopic conveying pipe, a negative pressure generator, a cleaning mechanism, a double-chamber collection box, a single-door shell, a control assembly, a generator, a towing mobile chassis, etc. During the harvest, the fresh jujubes on the branches are picked under the combined effect of the flexible squeezing of the picking roller and the suction force of the negative pressure air flow. They then enter the cleaning mechanism through the telescopic conveying pipe. Under the combined effect of the upper and lower baffles of the cleaning mechanism and the negative-pressure air flow, the fresh jujubes are separated from impurities such as jujube leaves and branches. The clean fresh jujubes fall into the collection box. We considered the damage rate of fresh jujubes, impurity rate, leakage rate, and harvesting efficiency as the indexes, and the negative-pressure suction wind speed, picking roller rotational speed, and the inclination angle of the upper and lower baffles of the cleaning and selection machinery as the test factors, and carried out the harvesting test of fresh jujubes. The test results show that when the negative-pressure suction wind speed was 25 m/s, the picking roller rotational speed was 31 r/min, and the inclination angles of the upper and lower baffle plates for cleaning and selecting were −19° and 19.5°, respectively, the breakage rate of fresh jujube harvesting was 0.90%, the rate of impurity was 1.54%, the rate of leakage was 2.59%, and the efficiency of harvesting was 73.37 kg/h, realizing the high-efficiency and low-loss harvesting of fresh jujubes. This study provides a reference for the research and development of fresh jujube mechanical harvesting technology and equipment. Full article
(This article belongs to the Section Precision and Digital Agriculture)
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24 pages, 1288 KiB  
Review
Counteracting the Harms of Microplastics on Humans: An Overview from the Perspective of Exposure
by Kuok Ho Daniel Tang
Microplastics 2025, 4(3), 47; https://doi.org/10.3390/microplastics4030047 - 1 Aug 2025
Viewed by 369
Abstract
Microplastics are pervasive environmental pollutants that pose risks to human health through ingestion and inhalation. This review synthesizes current practices to reduce exposure and toxicity by examining major exposure routes and dietary interventions. More than 130 papers were analyzed to achieve this aim. [...] Read more.
Microplastics are pervasive environmental pollutants that pose risks to human health through ingestion and inhalation. This review synthesizes current practices to reduce exposure and toxicity by examining major exposure routes and dietary interventions. More than 130 papers were analyzed to achieve this aim. The findings show that microplastics contaminate a wide range of food products, with particular concern over seafood, drinking water, plastic-packaged foods, paper cups, and tea filter bags. Inhalation exposure is mainly linked to indoor air quality and smoking, while dermal contact poses minimal risk, though the release of additives from plastics onto the skin remains an area of concern. Recommended strategies to reduce dietary exposure include consuming only muscle parts of seafood, moderating intake of high-risk items like anchovies and mollusks, limiting canned seafood liquids, and purging mussels in clean water before consumption. Avoiding plastic containers, especially for hot food or microwaving, using wooden cutting boards, paper tea bags, and opting for tap or filtered water over bottled water are also advised. To mitigate inhalation exposure, the use of air filters with HyperHEPA systems, improved ventilation, regular vacuuming, and the reduction of smoking are recommended. While antioxidant supplementation shows potential in reducing microplastic toxicity, further research is needed to confirm its effectiveness. This review provides practical, evidence-based recommendations for minimizing daily microplastic exposure. Full article
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31 pages, 6351 KiB  
Review
Recent Development on the Synthesis Strategies and Mechanisms of Co3O4-Based Electrocatalysts for Oxygen Evolution Reaction: A Review
by Liangjuan Gao, Yifan Jia and Hongxing Jia
Molecules 2025, 30(15), 3238; https://doi.org/10.3390/molecules30153238 - 1 Aug 2025
Viewed by 132
Abstract
The usage of fossil fuels has resulted in increasingly severe environmental problems, such as climate change, air pollution, water pollution, etc. Hydrogen energy is considered one of the most promising clean energies to replace fossil fuels due to its pollution-free and high-heat properties. [...] Read more.
The usage of fossil fuels has resulted in increasingly severe environmental problems, such as climate change, air pollution, water pollution, etc. Hydrogen energy is considered one of the most promising clean energies to replace fossil fuels due to its pollution-free and high-heat properties. However, the oxygen evolution reaction (OER) remains a critical challenge due to its high overpotential and slow kinetics during water electrolysis for hydrogen production. Electrocatalysts play an important role in lowering the overpotential of OER and promoting the kinetics. Co3O4-based electrocatalysts have emerged as promising candidates for the oxygen evolution reaction (OER) due to their favorable catalytic activity and good compatibility compared with precious metal-based electrocatalysts. This review presents a summary of the recent developments in the synthesis strategies and mechanisms of Co3O4-based electrocatalysts for the OER. Various synthesis strategies have been explored to control the size, morphology, and composition of Co3O4 nanoparticles. These strategies enable the fabrication of well-defined nanostructures with enhanced catalytic performance. Additionally, the mechanisms of OER catalysis on Co3O4-based electrocatalysts have been elucidated. Coordinatively unsaturated sites, synergistic effects with other elements, surface restructuring, and pH dependency have been identified as crucial factors influencing the catalytic activity. The understanding of these mechanisms provides insights into the design and optimization of Co3O4-based electrocatalysts for efficient OER applications. The recent advancements discussed in this review offer valuable perspectives for researchers working on the development of electrocatalysts for the OER, with the goal of achieving sustainable and efficient energy conversion and storage systems. Full article
(This article belongs to the Special Issue Emerging Multifunctional Materials for Next-Generation Energy Systems)
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40 pages, 910 KiB  
Review
Impact of Indoor Air Quality, Including Thermal Conditions, in Educational Buildings on Health, Wellbeing, and Performance: A Scoping Review
by Duncan Grassie, Kaja Milczewska, Stijn Renneboog, Francesco Scuderi and Sani Dimitroulopoulou
Environments 2025, 12(8), 261; https://doi.org/10.3390/environments12080261 - 30 Jul 2025
Viewed by 579
Abstract
Educational buildings, including schools, nurseries and universities, face stricter regulation and design control on indoor air quality (IAQ) and thermal conditions than other built environments, as these may affect children’s health and wellbeing. In this scoping review, wide-ranging health, performance, and absenteeism consequences [...] Read more.
Educational buildings, including schools, nurseries and universities, face stricter regulation and design control on indoor air quality (IAQ) and thermal conditions than other built environments, as these may affect children’s health and wellbeing. In this scoping review, wide-ranging health, performance, and absenteeism consequences of poor—and benefits of good—IAQ and thermal conditions are evaluated, focusing on source control, ventilation and air purification interventions. Economic impacts of interventions in educational buildings have been evaluated to enable the assessment of tangible building-related costs and savings, alongside less easily quantifiable improvements in educational attainment and reduced healthcare. Key recommendations are provided to assist decision makers in pathways to provide clean air, at an optimal temperature for students’ learning and health outcomes. Although the role of educational buildings can be challenging to isolate from other socio-economic confounders, secondary short- and long-term impacts on attainment and absenteeism have been demonstrated from the health effects associated with various pollutants. Sometimes overlooked, source control and repairing existing damage can be important cost-effective methods in minimising generation and preventing ingress of pollutants. Existing ventilation standards are often not met, even when mechanical and hybrid ventilation systems are already in place, but can often be achieved with a fraction of a typical school budget through operational and maintenance improvements, and small-scale air-cleaning and ventilation technologies, where necessary. Full article
(This article belongs to the Special Issue Air Pollution in Urban and Industrial Areas III)
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14 pages, 8566 KiB  
Article
An Evaluation of Mercury Accumulation Dynamics in Tree Leaves Growing in a Contaminated Area as Part of the Ecosystem Services: A Case Study of Turda, Romania
by Marin Senila, Cerasel Varaticeanu, Simona Costiug and Otto Todor-Boer
Land 2025, 14(8), 1529; https://doi.org/10.3390/land14081529 - 24 Jul 2025
Viewed by 275
Abstract
Mercury (Hg) poses a significant threat to human health and ecosystems, garnering increased attention in environmental studies. This paper evaluates the dynamics of Hg accumulation in various common tree leaves, specifically white poplar, linden, and cherry plum, throughout their growing season. The findings [...] Read more.
Mercury (Hg) poses a significant threat to human health and ecosystems, garnering increased attention in environmental studies. This paper evaluates the dynamics of Hg accumulation in various common tree leaves, specifically white poplar, linden, and cherry plum, throughout their growing season. The findings offer valuable insights into air quality and the ability of urban vegetation to mitigate mercury pollution in urban areas. A case study was conducted in Turda, a town in northwestern Romania, where a former chlor-alkali plant operated throughout the last century. Although the plant ceased its electrolysis activities over 25 years ago, the surrounding soil remains contaminated with mercury (Hg) due to the significant amounts released during its operation. The results indicated that the Hg concentration varied between 2.4 and 7.3 mg kg−1 dry weight (dw), exceeding the intervention threshold for soil of 2.0 mg kg−1. Additionally, the Hg content in the leaf samples consistently increased over time, influenced by leaf age and tree species. The Hg content increased in the following order: cherry plum < white poplar < linden. On average, white poplar leaves accumulated 72 ng Hg g−1 dw, linden leaves 128 ng Hg g−1 dw, and cherry plum leaves 47 ng Hg g−1 dw during the six-month monitored period from April to September. The results obtained can be used to evaluate the potential of different tree species for mitigating atmospheric Hg contamination and to elaborate on the suitable management of fallen leaves in the autumn. Full article
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37 pages, 1099 KiB  
Review
Application Advances and Prospects of Ejector Technologies in the Field of Rail Transit Driven by Energy Conservation and Energy Transition
by Yiqiao Li, Hao Huang, Shengqiang Shen, Yali Guo, Yong Yang and Siyuan Liu
Energies 2025, 18(15), 3951; https://doi.org/10.3390/en18153951 - 24 Jul 2025
Viewed by 323
Abstract
Rail transit as a high-energy consumption field urgently requires the adoption of clean energy innovations to reduce energy consumption and accelerate the transition to new energy applications. As an energy-saving fluid machinery, the ejector exhibits significant application potential and academic value within this [...] Read more.
Rail transit as a high-energy consumption field urgently requires the adoption of clean energy innovations to reduce energy consumption and accelerate the transition to new energy applications. As an energy-saving fluid machinery, the ejector exhibits significant application potential and academic value within this field. This paper reviewed the recent advances, technical challenges, research hotspots, and future development directions of ejector applications in rail transit, aiming to address gaps in existing reviews. (1) In waste heat recovery, exhaust heat is utilized for propulsion in vehicle ejector refrigeration air conditioning systems, resulting in energy consumption being reduced by 12~17%. (2) In vehicle pneumatic pressure reduction systems, the throttle valve is replaced with an ejector, leading to an output power increase of more than 13% and providing support for zero-emission new energy vehicle applications. (3) In hydrogen supply systems, hydrogen recirculation efficiency exceeding 68.5% is achieved in fuel cells using multi-nozzle ejector technology. (4) Ejector-based active flow control enables precise ± 20 N dynamic pantograph lift adjustment at 300 km/h. However, current research still faces challenges including the tendency toward subcritical mode in fixed geometry ejectors under variable operating conditions, scarcity of application data for global warming potential refrigerants, insufficient stability of hydrogen recycling under wide power output ranges, and thermodynamic irreversibility causing turbulence loss. To address these issues, future efforts should focus on developing dynamic intelligent control technology based on machine learning, designing adjustable nozzles and other structural innovations, optimizing multi-system efficiency through hybrid architectures, and investigating global warming potential refrigerants. These strategies will facilitate the evolution of ejector technology toward greater intelligence and efficiency, thereby supporting the green transformation and energy conservation objectives of rail transit. Full article
(This article belongs to the Special Issue Advanced Research on Heat Exchangers Networks and Heat Recovery)
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15 pages, 562 KiB  
Article
Transforming Agri-Waste into Health Innovation: A Circular Framework for Sustainable Food Design
by Smita Mortero, Jirarat Anuntagool, Achara Chandrachai and Sanong Ekgasit
Sustainability 2025, 17(15), 6712; https://doi.org/10.3390/su17156712 - 23 Jul 2025
Viewed by 406
Abstract
This study addresses the problem of agricultural waste utilization and nutrition for older adults by developing a food product based on a circular design approach. Pineapple core was used to produce a clean-label dietary powder without chemical or enzymatic treatment, relying on repeated [...] Read more.
This study addresses the problem of agricultural waste utilization and nutrition for older adults by developing a food product based on a circular design approach. Pineapple core was used to produce a clean-label dietary powder without chemical or enzymatic treatment, relying on repeated rinsing and hot-air drying. The development process followed a structured analysis of physical, chemical, and sensory properties. The powder contained 83.46 g/100 g dietary fiber, 0° Brix sugar, pH 4.72, low water activity (aw < 0.45), and no detectable heavy metals or microbial contamination. Sensory evaluation by expert panelists confirmed that the product was acceptable in appearance, aroma, and texture, particularly for older adults. These results demonstrate the feasibility and safety of valorizing agri-waste into functional ingredients. The process was guided by the Transformative Circular Product Blueprint, which integrates clean-label processing, IoT-enabled solar drying, and decentralized production. This model supports traceability, low energy use, and adaptation at the community scale. This study contributes to sustainable food innovation and aligns with Sustainable Development Goals (SDGs) 3 (Good Health and Well-being), 9 (Industry, Innovation and Infrastructure), and 12 (Responsible Consumption and Production). Full article
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19 pages, 9770 KiB  
Article
Microstructural Characterization of S355J2 Steel Plate Cut with Plasma in Water-Bed
by Teodor Machedon-Pisu, Mihai Machedon-Pisu and Arthur Olah
Coatings 2025, 15(8), 866; https://doi.org/10.3390/coatings15080866 - 23 Jul 2025
Viewed by 330
Abstract
When processing widely used materials in welded structures such as steels, a surface operation such as plasma cutting applied in the automated Computer Numerical Control (CNC) version can provide technical and economic benefits to the cut components, but the impact on health and [...] Read more.
When processing widely used materials in welded structures such as steels, a surface operation such as plasma cutting applied in the automated Computer Numerical Control (CNC) version can provide technical and economic benefits to the cut components, but the impact on health and environment must be addressed accordingly. In this paper, a plate with a base material made of S355J2 + AR structural steel is cut in 10 pieces with plasma in a water-bed designed and manufactured by the authors in order to mitigate such risks. The surfaces cut in the water-bed are compared to surfaces cut in open air by macroscopic analyses of the edge cut, by microscopic analyses of the cut parts—base material, heat-affected zone, and cut area—and by hardness determinations. The results reveal improvements as a result of plasma cutting in the water-bed: slag reduction, preservation of granulation, transformations in the austenitic temperature zone, and hardness in the heat-affected zone. Compared to a classical cutting procedure such as oxygen flame cutting, the proposed procedure offers a clean alternative and also requires low maintenance. Full article
(This article belongs to the Section Plasma Coatings, Surfaces & Interfaces)
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19 pages, 3112 KiB  
Article
Durable Superhydrophobic Composite Coating Based on Hydrangea-like SiO2 Nanoparticles with Excellent Performance in Anticorrosion, Drag Reduction, and Antifouling
by Yuhao Xue, Yamei Zhao, Xiaoqi Gu, Mengdan Huo, Kunde Yang, Mingyu Liu, Sixian Fan and Maoyong Zhi
Materials 2025, 18(15), 3443; https://doi.org/10.3390/ma18153443 - 23 Jul 2025
Viewed by 276
Abstract
Superhydrophobic coatings possess distinct wettability characteristics and hold significant potential in metal corrosion protection and underwater drag reduction. However, their practical application is often hindered by poor durability arising from the fragility of their micro/nanostructured surface roughness. In this study, a durable superhydrophobic [...] Read more.
Superhydrophobic coatings possess distinct wettability characteristics and hold significant potential in metal corrosion protection and underwater drag reduction. However, their practical application is often hindered by poor durability arising from the fragility of their micro/nanostructured surface roughness. In this study, a durable superhydrophobic coating featuring a hierarchical, hydrangea-like micro/nanostructure was successfully fabricated on an aluminum alloy substrate via a simple one-step cold-spraying technique. The coating consisted of hydrangea-shaped SiO2 nanoparticles modified with 1H,1H,2H,2H-perfluorodecyltrimethoxysilane (PFDT) to produce multiscale roughness, while epoxy resin (EP) served as the binding matrix to enhance mechanical integrity. The hydrangea-like SiO2 nanostructures were characterized by solid cores and wrinkled, petal-like outgrowths. This unique morphology not only increased the surface roughness but also provided more active sites for air entrapment, thereby enhancing the coating’s overall performance. The h-SiO2@PFDT-EP composite coating exhibited excellent superhydrophobicity, with a WCA of 170.1° ± 0.8° and a SA of 2.7° ± 0.5°. Durability was evaluated through sandpaper abrasion, tape peeling, acid and alkali immersion, artificial weathering, and salt spray tests. The results demonstrated that the coating retained stable superhydrophobic performance under various environmental stresses. Compared with bare 6061 aluminum and EP coatings, its corrosion current density was reduced by four and three orders of magnitude, respectively. Furthermore, the coating achieved a maximum drag-reduction rate of 31.01% within a velocity range of 1.31–7.86 m/s. The coating also displayed excellent self-cleaning properties. Owing to its outstanding durability, corrosion resistance, and drag-reducing capability, this one-step fabricated superhydrophobic coating showed great promise for applications in marine engineering and defense. Full article
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17 pages, 1310 KiB  
Article
Assessment of Suppressive Effects of Negative Air Ions on Fungal Growth, Sporulation and Airborne Viral Load
by Stefan Mijatović, Andrea Radalj, Andjelija Ilić, Marko Janković, Jelena Trajković, Stefan Djoković, Borko Gobeljić, Aleksandar Sovtić, Gordana Petrović, Miloš Kuzmanović, Jelena Antić Stanković, Predrag Kolarž and Irena Arandjelović
Atmosphere 2025, 16(8), 896; https://doi.org/10.3390/atmos16080896 - 22 Jul 2025
Viewed by 350
Abstract
Spores of filamentous fungi are common biological particles in indoor air that can negatively impact human health, particularly among immunocompromised individuals and patients with chronic respiratory conditions. Airborne viruses represent an equally pervasive threat, with some carrying the potential for pandemic spread, affecting [...] Read more.
Spores of filamentous fungi are common biological particles in indoor air that can negatively impact human health, particularly among immunocompromised individuals and patients with chronic respiratory conditions. Airborne viruses represent an equally pervasive threat, with some carrying the potential for pandemic spread, affecting both healthy individuals and the immunosuppressed alike. This study investigated the abundance and diversity of airborne fungal spores in both hospital and residential environments, using custom designed air samplers with or without the presence of negative air ions (NAIs) inside the sampler. The main purpose of investigation was the assessment of biological effects of NAIs on fungal spore viability, deposition, mycelial growth, and sporulation, as well as airborne viral load. The precise assessment of mentioned biological effects is otherwise difficult to carry out due to low concentrations of studied specimens; therefore, specially devised and designed, ion-bioaerosol interaction air samplers were used for prolonged collection of specimens of interest. The total fungal spore concentrations were quantified, and fungal isolates were identified using cultural and microscopic methods, complemented by MALDI-TOF mass spectrometry. Results indicated no significant difference in overall spore concentration between environments or treatments; however, presence of NAIs induced a delay in the sporulation process of Cladosporium herbarum, Aspergillus flavus, and Aspergillus niger within 72 h. These effects of NAIs are for the first time demonstrated in this work; most likely, they are mediated by oxidative stress mechanisms. A parallel experiment demonstrated a substantially reduced concentration of aerosolized equine herpesvirus 1 (EHV-1) DNA within 10–30 min of exposure to NAIs, with more than 98% genomic load reduction beyond natural decay. These new results on the NAIs interaction with a virus, as well as new findings regarding the fungal sporulation, resulted in part from a novel interaction setup designed for experiments with the bioaerosols. Our findings highlight the potential of NAIs as a possible approach for controlling fungal sporulation and reducing airborne viral particle quantities in indoor environments. Full article
(This article belongs to the Section Aerosols)
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24 pages, 13010 KiB  
Article
Dual-Vortex Aerosol Mixing Chamber for Micrometer Aerosols: Parametric CFD Analysis and Experimentally Validated Design Improvements
by Ziran Xu, Junjie Liu, Yue Liu, Jiazhen Lu and Xiao Xu
Processes 2025, 13(8), 2322; https://doi.org/10.3390/pr13082322 - 22 Jul 2025
Viewed by 329
Abstract
Aerosol uniformity in the mixing chamber is one of the key factors in evaluating performance of aerosol samplers and accuracy of aerosol monitors which could output the direct reading of particle size or concentration. For obtaining high uniformity and a stable test aerosol [...] Read more.
Aerosol uniformity in the mixing chamber is one of the key factors in evaluating performance of aerosol samplers and accuracy of aerosol monitors which could output the direct reading of particle size or concentration. For obtaining high uniformity and a stable test aerosol sample during evaluation, a portable mixing chamber, where the sample and clean air were dual-vortex turbulent mixed, was designed. By using computational fluid dynamics (CFD), particle motion within the mixing chamber was illustrated or explained. By adjusting critical structure parameters of chamber such as height and diameter, the flow field structure was optimized to improve particle mixing characteristics. Accordingly, a novel portable aerosol mixing chamber with length and inner diameter of 0.7 m and 60 mm was developed. Through a combination of simulations and experiments, the operating conditions, including working flow rate, ratio of carrier/dilution clean air, and mixture duration, were studied. Finally, by using the optimized parameters, a mixing chamber with high spatial uniformity where variation is less than 4% was obtained for aerosol particles ranging from 0.3 μm to 10 μm. Based on this chamber, a standardized testing platform was established to verify the sampling efficiency of aerosol samplers with high flow rate (28.3 L·min−1). The obtained results were consistent with the reference values in the sampler’s manual, confirming the reliability of the evaluation system. The testing platform developed in this study can provide test aerosol particles ranging from sub-micrometers to micrometers and has significant engineering applications, such as atmospheric pollution monitoring and occupational health assessment. Full article
(This article belongs to the Section Particle Processes)
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