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21 pages, 7458 KB  
Article
Comparative Study Between Citric Acid and Glutaraldehyde in the Crosslinking of Gelatine Hydrogels Reinforced with Cellulose Nanocrystals (CNC)
by Diana Carmona-Cantillo, Rafael González-Cuello and Rodrigo Ortega-Toro
Gels 2025, 11(10), 790; https://doi.org/10.3390/gels11100790 - 1 Oct 2025
Abstract
Hydrogels comprise three-dimensional networks of hydrophilic polymers and have attracted considerable interest in various sectors, including the biomedical, pharmaceutical, agricultural, and food industries. These materials offer significant benefits for food packaging applications, such as high mechanical strength and excellent water absorption capacity, thereby [...] Read more.
Hydrogels comprise three-dimensional networks of hydrophilic polymers and have attracted considerable interest in various sectors, including the biomedical, pharmaceutical, agricultural, and food industries. These materials offer significant benefits for food packaging applications, such as high mechanical strength and excellent water absorption capacity, thereby contributing to the extension of product shelf life. Therefore, the aim of this study is to compare the performance of citric acid and glutaraldehyde as crosslinking agents in gelatine-based hydrogels reinforced with cellulose nanocrystals (CNC), contributing to the development of safe and environmentally responsible materials. The hydrogels were prepared using the casting method and characterised in terms of their physical, mechanical, and structural properties. The results indicated that hydrogels crosslinked with glutaraldehyde exhibited higher opacity, lower transparency, and greater mechanical strength, whereas those crosslinked with citric acid demonstrated improved clarity, reduced water permeability, and enhanced swelling capacity. The incorporation of CNC further improved mechanical strength, reduced weight loss, and altered both surface homogeneity and optical properties. Microstructural results obtained by SEM were consistent with the mechanical properties evaluated (TS, %E, and EM). The Gel-ca hydrogel displayed the highest elongation value (98%), reflecting better cohesion within the polymeric matrix. In contrast, films incorporating CNC exhibited greater roughness and cracking, which correlated with increased rigidity and mechanical strength, as evidenced by the high Young’s modulus (420 MPa in Gel-ga-CNC2). These findings suggest that the heterogeneity and porosity induced by CNC limit the mobility of polymer chains, resulting in less flexible and more rigid structures. Additionally, the DSC analysis revealed that gelatine hydrogels did not exhibit a well-defined Tg, due to the predominance of crystalline domains. Systems crosslinked with citric acid showed greater thermal stability (higher Tm and ΔHm values), while those crosslinked with glutaraldehyde, although mechanically stronger, exhibited lower thermal stability. These results confirm the decisive effect of the crosslinking agent and CNC incorporation on the structural and thermal behaviour of hydrogels. In this context, the application of hydrogels in packaged products represents an eco-friendly alternative that enhances product presentation. This research supports the reduction in plastic consumption whilst promoting the principles of a circular economy and facilitating the development of materials with lower environmental impact. Full article
(This article belongs to the Special Issue Recent Advances in Biopolymer Gels (2nd Edition))
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21 pages, 3445 KB  
Article
Optimization of the Borehole Wall Protection Slurry Ratio and Film-Forming Mechanism in Water-Rich Sandy Strata
by Xiaodong Liu, Meng Li, Peiyue Qiu, Liyun Tang, Zhenghong Liu and Fusheng Zhang
Eng 2025, 6(10), 251; https://doi.org/10.3390/eng6100251 - 1 Oct 2025
Abstract
Conventional slurry wall protection exhibits reduced film performance upon exposure to water in saturated sand layers with high permeability, frequently resulting in hole wall instability. Optimizing the slurry ratio to enhance film performance is thus critical for borehole stability. A multiple regression model [...] Read more.
Conventional slurry wall protection exhibits reduced film performance upon exposure to water in saturated sand layers with high permeability, frequently resulting in hole wall instability. Optimizing the slurry ratio to enhance film performance is thus critical for borehole stability. A multiple regression model was developed to determine the optimal slurry ratio for saturated sand. Slurry permeability tests assessed filtration loss, film formation time, and film morphology changes. Scanning electron microscopy (SEM) further elucidated the film formation mechanism. Bentonite, clay, Na2CO3, and sodium carboxymethyl cellulose (CMC) significantly affected the slurry’s properties: specific gravity and sand content increased with bentonite/clay; viscosity increased with CMC; and pH increased with Na2CO3. The optimized slurry (water–bentonite–Na2CO3–clay–CMC = 1000:220:32:110:1; specific gravity, 1.20 g/cm3; viscosity, 29 s) demonstrated low filtration loss and stable film morphology. SEM revealed that simultaneous CMC and clay addition (ratio of 1:110) improved film surface flatness, reduced porosity and pore size, enhanced formation surface filling, and produced a denser film. The optimized slurry ratio significantly enhanced film performance in saturated sand layers. The findings provide a theoretical and engineering framework for bored pile wall protection slurry design and film formation mechanisms. Full article
(This article belongs to the Section Chemical, Civil and Environmental Engineering)
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15 pages, 10073 KB  
Article
Defect Engineering in Fluorinated Metal–Organic Frameworks Within Mixed-Matrix Membranes for Enhanced CO2 Separation
by Benxing Li, Lei Wang, Yizheng Tao, Rujing Hou and Yichang Pan
Membranes 2025, 15(10), 296; https://doi.org/10.3390/membranes15100296 - 30 Sep 2025
Abstract
Developing highly permeable and selective membranes for energy-efficient CO2/CH4 separation remains challenging. Mixed-matrix membranes (MMMs) integrating polymer matrices with metal–organic frameworks (MOFs) offer significant potential. However, rational filler–matrix matching presents substantial difficulties, constraining separation performance. In this work, defects were [...] Read more.
Developing highly permeable and selective membranes for energy-efficient CO2/CH4 separation remains challenging. Mixed-matrix membranes (MMMs) integrating polymer matrices with metal–organic frameworks (MOFs) offer significant potential. However, rational filler–matrix matching presents substantial difficulties, constraining separation performance. In this work, defects were engineered within fluorinated MOF ZU-61 through the partial replacement of 4,4′-bipyridine linkers with pyridine modulators, producing high-porosity HP-ZU-61 nanoparticles exhibiting a 267% BET surface area enhancement (992.9 m2 g−1) over low-porosity ZU-61 (LP-ZU-61) (372.2 m2 g−1). The HP-ZU-61/6FDA-DAM MMMs (30 wt.%) demonstrated homogeneous filler dispersion and pre-served crystallinity, achieving a CO2 permeability of 1626 barrer and CO2/CH4 selectivity (33), surpassing the 2008 Robeson upper bound. Solution-diffusion modeling indicated ligand deficiencies generated accelerated diffusion pathways, while defect-induced unsaturated metal sites functioned as strong CO2 adsorption centers that maintained solubility selectivity. This study establishes defect engineering in fluorinated MOF-based MMMs as a practical strategy to concurrently overcome the permeability–selectivity trade-off for efficient CO2 capture. Full article
(This article belongs to the Special Issue Functional Composite Membranes: Properties and Applications)
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25 pages, 5751 KB  
Article
Optimization of Nano-SiO2/Tea Polyphenol/Pullulan Edible Composite Films for Postharvest Preservation of Cherry Tomatoes
by Peng Huang, Jie Ding, Yu Han, Ling Gong, Fang Wu, Yaowen Liu, Pinyao Zhao, Zuying Yang, Lin Ye, Shanshan Zhou and Wen Qin
Foods 2025, 14(19), 3386; https://doi.org/10.3390/foods14193386 - 30 Sep 2025
Abstract
Edible composite coatings represent an alternative approach to reducing postharvest losses and extending the shelf life of perishable fruits. This study developed a nano-biopolymer coating by integrating pullulan (PUL), nano-silica (Nano-SiO2), and tea polyphenols (TP) to retard deterioration in cherry tomatoes [...] Read more.
Edible composite coatings represent an alternative approach to reducing postharvest losses and extending the shelf life of perishable fruits. This study developed a nano-biopolymer coating by integrating pullulan (PUL), nano-silica (Nano-SiO2), and tea polyphenols (TP) to retard deterioration in cherry tomatoes (Solanum lycopersicum var. cerasiforme). Optimized through response surface methodology (0.06% Nano-SiO2, 0.1% TP, 1.8% PUL, 0.77% glycerol), the resulting Nano-SiO2/PUL/TP composite film showed improved barrier properties (water vapor permeability, WVP: 0.2063 g·mm·m−2·h−1·kPa−1) and increased mechanical strength (tensile strength, TS: 2.62 MPa; elongation at break, EB: 67.67%), which may be attributed to a homogeneous microstructure stabilized via intermolecular hydrogen bonding. The composite coating exhibited significant (p < 0.05) antioxidant activity (59.04% DPPH·scavenging) compared to the PUL film (1.17%) and showed efficacy against S. aureus. When applied to cherry tomatoes stored at 4 °C for 15 days, the coating contributed to improved postharvest quality by reducing weight loss (−27.6%) and decay incidence (−32.3%), delaying firmness loss (2.40 vs. 0.54 N in uncoated group, CK), suppressing respiration rate (−38.8%), and enhancing the retention of total acidity (+9.7%), vitamin C (+49.6%), and total soluble solids (+48.6%) compared to the CK (p < 0.05). Principal component analysis supported sensory evaluation results, indicating the coating helped maintain sensory quality (scores > 6.0) and commercial value while extending shelf life from 9 to 15 days. These results suggest that the Nano-SiO2/TP/PUL composite coating may serve as a preservative for extending the shelf-life of cherry tomatoes by effectively reducing decay and mitigating quality degradation. Full article
(This article belongs to the Section Food Packaging and Preservation)
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25 pages, 1215 KB  
Article
Do Oxytetracycline and Ciprofloxacin Affect Growth Phenotype, Leaf Photosynthetic Enzyme Activity, Nitrogen Metabolism, and Endogenous Hormone Homeostasis in Maize Seedlings?
by Mingquan Wang, Yong Wang, Guoliang Li, Guanghui Hu, Lixin Fu, Shaoxin Hu, Jianfei Yang and Zhiguo Wang
Plants 2025, 14(19), 3021; https://doi.org/10.3390/plants14193021 - 30 Sep 2025
Abstract
The wide use of antibiotics in multiple fields leads to their entry into the environment, challenging agriculture and ecology and potentially affecting maize seedling growth. In this study, maize variety Longken 10 was chosen as the experimental material. Subsequently, two antibiotics commonly utilized [...] Read more.
The wide use of antibiotics in multiple fields leads to their entry into the environment, challenging agriculture and ecology and potentially affecting maize seedling growth. In this study, maize variety Longken 10 was chosen as the experimental material. Subsequently, two antibiotics commonly utilized in production, namely oxytetracycline (OTC) belonging to the tetracycline class and ciprofloxacin (CIP) from the quinolone class, were selected. To comprehensively examine the impacts of these antibiotics on the phenotype, photosynthetic enzymes, nitrogen metabolism, and endogenous hormone contents of maize seedlings, a series of different concentration gradients (0, 3, 5, 30, 60, and 120 mg·L−1) were established, and the nutrient solution hydroponic method was employed. The results showed that, compared with the control group (CK), the activities of all indicators of maize seedlings were the strongest and the seedling growth was the most vigorous when the concentration of CIP was 5 mg·L−1 and that of OTC was 3 mg·L−1. The inhibitory effect of OTC on various indicators of maize seedlings was stronger than that of CIP. The underground parts of maize seedlings were more sensitive to OTC and CIP than the aboveground parts. Overall, maize seedlings exhibited a trend where high concentrations (30–120 mg·L−1) of antibiotics inhibited growth, while low concentrations (3–5 mg·L−1) promoted growth. The treatment groups with 3–5 mg·L−1 of OTC and CIP increased maize seedling growth phenotypes, the robust growth of seedlings with enhanced vitality, and the relative water content of maize leaves; decreased the relative electrical conductivity of maize leaves, indicating reduced cell permeability; increased the activities of leaf photosynthetic enzymes (PEPCase, RUBPCase, PPDK, NADP-ME, and NADP-MDH); increased the levels of hormones (IAA, GA, and ZR) in maize leaves and roots; decreased the levels of ABA and MeJA; increased the levels of nitrogen metabolism-related enzymes (GS, GOGAT, and GAD) in roots and leaves; decreased the GDH level; enhanced root activity and increased various root parameters (including average diameter, number of root tips, total volume, total root length, and root surface area), indicating vigorous root growth. Compared with CK, the treatment groups with 30–120 mg·L−1 of OTC and CIP reduced the phenotypes of maize seedlings, decreased the relative water content of maize leaves and increased the relative electrical conductivity of maize leaves, indicating enhanced cell permeability; reduced the activity of leaf photosynthetic enzymes, leading to weakened photosynthesis and decreased photosynthetic productivity; lowered the levels of IAA, GA, and ZR in leaves and roots of maize seedlings, and increased the levels of ABA and MeJA; decreased the levels of GS, GOGAT, and GAD in leaves and roots of maize seedlings, and increased the GDH level; reduced root activity, with the corresponding decrease in various root parameters. Full article
(This article belongs to the Special Issue Physiological Ecology and Regulation of High-Yield Maize Cultivation)
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12 pages, 2676 KB  
Article
The Dual Effect of Hematite-Amended Constructed Wetlands: Reducing the Toxicity of SMX Degradation Products and Increasing the Dissemination of Antibiotic Resistance Genes
by Shiwen Zhang, Xin Zhang, Fengkai Sun, Chaoyu Li, Zhen Hu, Shuang Liang and Huijun Xie
Water 2025, 17(19), 2850; https://doi.org/10.3390/w17192850 - 30 Sep 2025
Abstract
Iron ore may enhance the treatment performance of antibiotics within constructed wetlands (CWs), but its effects on the toxicity of degradation products and antibiotic resistance genes require further investigation. This study investigated the sulfamethoxazole (SMX) removal efficiency, SMX degradation pathway, and dissemination of [...] Read more.
Iron ore may enhance the treatment performance of antibiotics within constructed wetlands (CWs), but its effects on the toxicity of degradation products and antibiotic resistance genes require further investigation. This study investigated the sulfamethoxazole (SMX) removal efficiency, SMX degradation pathway, and dissemination of antibiotic resistance genes (sul1 and sul2) linked to SMX in hematite-amended CW microcosms. Hematite, due to its large specific surface area and formation of high redox potential, promoted SMX removal (99.05–99.26%) by adsorption, thus enhancing microbial biodegradation. The addition of hematite increased SMX degradation pathways and simultaneously attenuated the ecotoxicity of intermediate products. However, hematite also stimulated the production of extracellular polymeric substances by microorganisms, enhancing cell–cell adhesion and increasing membrane permeability, ultimately leading to a rise in the abundance of sul1 and sul2. Therefore, although iron ore provides benefits in practical applications, the potential environmental risks it poses deserve serious consideration. Full article
(This article belongs to the Special Issue Impacts of Climate Change & Human Activities on Wetland Ecosystems)
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17 pages, 2324 KB  
Article
Laboratory Experiments Unravel the Mechanisms of Snowmelt Erosion in Northeast China’s Black Soil: The Key Role of Supersaturation-Driven and Layered Moisture Migration
by Songshi Zhao, Haoming Fan and Maosen Lin
Sustainability 2025, 17(19), 8737; https://doi.org/10.3390/su17198737 - 29 Sep 2025
Abstract
Snowmelt runoff is a major soil erosion trigger in mid-to-high latitude and altitude regions. Through runoff plot observations and simulations in the northeastern black soil region, this study reveals the key regulatory mechanism of water migration on snowmelt erosion. Results demonstrate that the [...] Read more.
Snowmelt runoff is a major soil erosion trigger in mid-to-high latitude and altitude regions. Through runoff plot observations and simulations in the northeastern black soil region, this study reveals the key regulatory mechanism of water migration on snowmelt erosion. Results demonstrate that the interaction between thawed upper and frozen lower soil layers creates a significant hydraulic gradient during snowmelt. Impermeability of the frozen layer causes meltwater accumulation and moisture supersaturation (>47%, exceeding field capacity) in the upper layer. Freeze–thaw action accelerates vertical moisture migration and redistributes shallow moisture by increasing porosity. This process causes soils with high initial moisture to reach supersaturation faster, triggering earlier and more frequent erosion. Gray correlation analysis shows that soil moisture migration’s contribution to erosion intensity is layered: migration in shallow soil (0–10 cm) correlates most strongly with surface erosion; migration in deep soil (10–15 cm) exhibits a U-shaped contribution due to freeze–thaw front boundary effects. A regression model identified key controlling factors (VIP > 1.0): changes in bulk density, porosity, and permeability of deep soil significantly regulate erosion intensity. The nonlinear relationship between erosion intensity and moisture content (R2 = 0.82) confirms supersaturation dominance. Physical structure and mechanical properties of unfrozen layers regulate erosion dynamics via moisture migration. These findings clarify the key mechanism of moisture migration governing snowmelt erosion, providing a critical scientific foundation for developing targeted soil conservation strategies and advancing regional prediction models essential for sustainable land management under changing winter climates. Full article
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15 pages, 2521 KB  
Article
Enhanced Oil Recovery Mechanism and Parameter Optimization of Huff-and-Puff Flooding with Oil Displacement Agents in the Baikouquan Oilfield
by Hui Tian, Jianye Mou, Kunlin Xue, Xingyu Yi, Hao Liu and Budong Gao
Processes 2025, 13(10), 3098; https://doi.org/10.3390/pr13103098 - 27 Sep 2025
Abstract
The Baikouquan Oilfield edge expansion wells suffer from poor reservoir properties and limited connectivity, leading to low waterflooding sweep efficiency and insufficient reservoir energy. While oil displacement agents (ODAs) are currently employed in huff-and-puff flooding to enhance recovery, there is a lack of [...] Read more.
The Baikouquan Oilfield edge expansion wells suffer from poor reservoir properties and limited connectivity, leading to low waterflooding sweep efficiency and insufficient reservoir energy. While oil displacement agents (ODAs) are currently employed in huff-and-puff flooding to enhance recovery, there is a lack of a solid basis for selecting these ODAs, and the dominant mechanisms of enhanced oil recovery (EOR) remain unclear. To address this issue, this study combines experimental work and reservoir numerical simulation to investigate the mechanisms of EOR by ODAs, optimize the selection of ODAs, and fine-tune the huff-and-puff flooding parameters. The results show that the selected nanoemulsion ODA (Nano ODA) significantly reduces the oil–water interfacial tension (IFT) by 97%, thereby increasing capillary number. Additionally, the ODA induces a shift from water–wet to neutral–wet conditions on rock surfaces, reducing capillary forces and weakening spontaneous imbibition. The Nano ODA demonstrates strong emulsification and oil-carrying ability, with an emulsification efficiency of 75%. Overall, the ODA increases the relative permeability of the oil phase, reduces residual oil saturation, and achieves a recovery improvement of more than 10% compared with conventional waterflooding. The injection volume and shut-in time were optimized for the target well, and the recovery enhancement from multiple cycles of huff-and-puff flooding was predicted. The research in this paper is expected to provide guidance for the design of huff-and-puff flooding schemes in low-permeability reservoirs. Full article
(This article belongs to the Special Issue Recent Advances in Hydrocarbon Production Processes from Geoenergy)
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22 pages, 5366 KB  
Article
Influence of Water Level Change on Vibration Response and Isolation of Saturated Soil Under Moving Loads
by Jinbao Yao, Yueyue Chen and Longhua Dong
Appl. Sci. 2025, 15(19), 10461; https://doi.org/10.3390/app151910461 - 26 Sep 2025
Abstract
This paper investigates the influence of groundwater level fluctuations on the vibration response and isolation performance of saturated soil foundations under moving loads. A coupled model consisting of an overlying elastic layer and a saturated half-space is established, with water level variation simulated [...] Read more.
This paper investigates the influence of groundwater level fluctuations on the vibration response and isolation performance of saturated soil foundations under moving loads. A coupled model consisting of an overlying elastic layer and a saturated half-space is established, with water level variation simulated by adjusting the elastic layer thickness. Using Biot’s theory and Fourier transforms, the dynamic response is solved analytically and validated numerically via COMSOL6.0 simulations with perfectly matched layers. Results indicate that the groundwater level significantly affects wave propagation: deeper water levels lead to responses resembling an elastic half-space, while rising water levels amplify surface displacement due to wave reflection at the saturation interface. As water levels approach the surface, behavior converges to that of a fully saturated foundation. P-wave resonance at certain water levels reduces isolation effectiveness. Furthermore, isolation performance is sensitive to load frequency, soil permeability, and trench dimensions. These findings offer valuable insights for designing vibration mitigation measures in environments with variable groundwater conditions. Full article
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20 pages, 3372 KB  
Article
Characterization and Performance Evaluation of Cotton Fabrics Functionalized via In Situ Green Synthesis of Silver Nanoparticles Using Solanum tuberosum Peel Extract
by Nonsikelelo Sheron Mpofu, Josphat Igadwa Mwasiagi, Cleophas Achisa Mecha and Eric Oyondi Nganyi
Polymers 2025, 17(19), 2598; https://doi.org/10.3390/polym17192598 - 25 Sep 2025
Abstract
The functionalization of textiles with nanomaterials through green synthesis offers a promising pathway for sustainable material innovation. This study explores the in situ green synthesis of silver nanoparticles (AgNPs) onto cotton fabrics using Solanum tuberosum (potato) peel extract as a natural reducing and [...] Read more.
The functionalization of textiles with nanomaterials through green synthesis offers a promising pathway for sustainable material innovation. This study explores the in situ green synthesis of silver nanoparticles (AgNPs) onto cotton fabrics using Solanum tuberosum (potato) peel extract as a natural reducing and stabilizing agent. The synthesis conditions were optimized by varying silver nitrate concentration, extract volume, temperature, pH, and reaction time, after which the optimized protocol was applied for fabric treatment. The presence and distribution of AgNPs were confirmed through UV-Visible spectroscopy, Fourier-transform infrared spectroscopy, scanning electron microscopy and dynamic light scattering. The treated fabrics demonstrated strong and durable antibacterial performance, with inhibition zones of 23 ± 0.02 against Escherichia coli and 16 ± 0.01 against Staphylococcus aureus. Notably, antibacterial activity was retained even after 20 washing cycles, demonstrating the durability of the treatment. Mechanical testing revealed a 32.25% increase in tensile strength and a corresponding 10.47% reduction in elongation at break compared to untreated fabrics, suggesting improved durability with moderate stiffness. Air permeability decreased by 8.8%, correlating with the rougher surface morphology observed in Scanning Electron Microscopy images. Thermal analysis showed a decrease in thermal stability relative to untreated cotton, highlighting the influence of AgNPs on degradation behavior. Overall, this work demonstrates that potato peel waste, an abundant and underutilized biomass, can be used as a sustainable source for the green synthesis of AgNP-functionalized textiles. The approach provides a cost-effective and environmentally friendly strategy for developing multifunctional fabrics, while supporting circular economy goals in textile engineering. Full article
(This article belongs to the Special Issue Sustainable Electrospinning Processes and Green Solvents)
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21 pages, 5935 KB  
Article
A Superhydrophobic Gel Fracturing Fluid with Enhanced Structural Stability and Low Reservoir Damage
by Qi Feng, Quande Wang, Naixing Wang, Guancheng Jiang, Jinsheng Sun, Jun Yang, Tengfei Dong and Leding Wang
Gels 2025, 11(10), 772; https://doi.org/10.3390/gels11100772 - 25 Sep 2025
Abstract
Conventional fracturing fluids, while essential for large-volume stimulation of unconventional reservoirs, often induce significant reservoir damage through water retention and capillary trapping. To address this problem, this study developed a novel superhydrophobic nano-viscous drag reducer (SN-DR), synthesized through a multi-monomer copolymerization and silane [...] Read more.
Conventional fracturing fluids, while essential for large-volume stimulation of unconventional reservoirs, often induce significant reservoir damage through water retention and capillary trapping. To address this problem, this study developed a novel superhydrophobic nano-viscous drag reducer (SN-DR), synthesized through a multi-monomer copolymerization and silane modification strategy, which enhances structural stability and minimizes reservoir damage. The structure and thermal stability of SN-DR were characterized by FT-IR, 1H NMR, and TGA. Rheological evaluations demonstrated that the gel fracturing fluid exhibits a highly stable three-dimensional network structure, with a G′ maintained at approximately 3000 Pa and excellent shear recovery under cyclic stress. Performance tests showed that a 0.15% SN-DR achieved a drag reduction rate of 78.1% at 40 L/min, reduced oil–water interfacial tension to 0.91 mN·m−1, and yielded a water contact angle of 152.07°, confirming strong hydrophobicity. Core flooding tests revealed a flowback rate exceeding 50% and an average permeability recovery of 86%. SEM and EDS indicated that the gel formed nanoscale, tightly packed papillary structures on core surfaces, enhancing roughness and reducing water intrusion. The study demonstrates that gel fracturing fluid enhances structural stability, alters wettability, and mitigates water-blocking damage. These findings offer a new strategy for designing high-performance fracturing fluids with integrated drag reduction and reservoir protection properties, providing significant theoretical insights for improving hydraulic fracturing efficiency. Full article
(This article belongs to the Section Gel Applications)
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6 pages, 2980 KB  
Proceeding Paper
Cooling Urban Municipalities Through Sustainable Microclimate Interventions: The Case of Kallithea in the Greater Athens Area
by Thomas Stavropoulos, Elissavet Feloni, Chrysovalanti-Charikleia Prokopiadi, Maria Sklia, George Hloupis and Panagiotis T. Nastos
Environ. Earth Sci. Proc. 2025, 35(1), 45; https://doi.org/10.3390/eesp2025035045 - 25 Sep 2025
Abstract
Urbanization and intensified human activity have significantly impacted city climates, amplifying the urban heat island effect and increasing thermal stress on residents. This study focuses on the design of a pocket park in the Municipality of Kallithea as a targeted bioclimatic intervention. Through [...] Read more.
Urbanization and intensified human activity have significantly impacted city climates, amplifying the urban heat island effect and increasing thermal stress on residents. This study focuses on the design of a pocket park in the Municipality of Kallithea as a targeted bioclimatic intervention. Through the integration of on-site microclimate measurements, GIS mapping, and 2D design tools, the research evaluates key bioclimatic indicators to inform climate-responsive design strategies. Proposed solutions include the use of cool materials, reflective surfaces, permeable pavements, and water features to enhance natural ventilation and mitigate surface temperatures. The project demonstrates how small-scale green infrastructure can improve thermal comfort in dense urban areas while supporting sustainability goals. By highlighting the potential of localized interventions, the study contributes to the broader discourse on urban resilience and the role of bioclimatic planning in creating healthier, more livable cities. Full article
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17 pages, 6943 KB  
Article
Flux and Fouling Behavior of Graphene Oxide-Polyphenylsulfone Ultrafiltration Membranes Incorporating ZIF-67/ZIF-8 Fillers
by Azile Nqombolo, Thollwana Andretta Makhetha, Richard Motlhaletsi Moutloali and Philiswa Nosizo Nomngongo
Membranes 2025, 15(10), 289; https://doi.org/10.3390/membranes15100289 - 25 Sep 2025
Abstract
Wider adoption of membrane technology is hindered by fouling and flux/rejection challenges. Recent practice in mitigating these is to incorporate hydrophilic and porous fillers. Herein the addition of hydrophilic graphene oxide (GO) in conjunction with porous mixed ZIFs (ZIF-67/ZIF-8) crystallites were used as [...] Read more.
Wider adoption of membrane technology is hindered by fouling and flux/rejection challenges. Recent practice in mitigating these is to incorporate hydrophilic and porous fillers. Herein the addition of hydrophilic graphene oxide (GO) in conjunction with porous mixed ZIFs (ZIF-67/ZIF-8) crystallites were used as inorganic fillers in the preparation of polyphenylenesulfone (PPSU) ultrafiltration (UF) membranes. The morphology of the resultant composite membranes was assessed using atomic force microscopy (AFM) and scanning electron microscopy (SEM) whilst surface hydrophilicity through water contact angle. The pure water flux (PWF) and membrane permeability were found to increase with increasing filler content. This was attributed to the combined hydrophilicity of GO and porous structure of the ZIF materials because of increasing alternative water pathways in the membrane matrix with increasing filler content. Furthermore, the increase in the ZIF component led to increasing bovine serum albumin (BSA) fouling resistance as demonstrated by increasing fouling recovery ratio (FRR). The dye rejection was due to a combination of electrostatic interaction between the fillers and the dyes as well as size exclusion. The chemical interactions between the ZIFs and the dyes resulted in slightly different rejection profiles for the smaller dyes, the cationic methylene blue being rejected less efficiently than the anionic methyl orange, potentially leading to their separation. The larger anionic dye, Congo red was rejected predominately through size exclusion. Full article
(This article belongs to the Special Issue Design, Preparation and Application of Nanocomposite Membranes)
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26 pages, 6715 KB  
Article
The Effect of Long-Term Betacoronavirus Infection on the Permeability of the Blood–Brain Barrier—In Vitro Model Studies
by Weronika Daria Krahel, Marcin Chodkowski, Michalina Bartak, Agnieszka Ostrowska, Michał M. Godlewski, Maksymilian Adamczyk, Małgorzata Krzyżowska and Joanna Cymerys
Cells 2025, 14(19), 1493; https://doi.org/10.3390/cells14191493 - 24 Sep 2025
Viewed by 68
Abstract
The blood–brain barrier (BBB) is critical for central nervous system homeostasis, yet it is highly vulnerable to viral insults. While acute coronavirus infections are known to impair BBB integrity, the long-term impact of persistent infection on brain endothelial cells remains poorly understood. Using [...] Read more.
The blood–brain barrier (BBB) is critical for central nervous system homeostasis, yet it is highly vulnerable to viral insults. While acute coronavirus infections are known to impair BBB integrity, the long-term impact of persistent infection on brain endothelial cells remains poorly understood. Using an in vitro BBB model, we examined the effects of a 12-week infection with the neurotropic murine coronavirus MHV-JHM. Structural and functional changes were assessed via fluorescein isothiocyanate (FITC)-dextran permeability assay, confocal imaging of mitochondria, actin cytoskeleton, reactive oxygen species (ROS), scanning electron microscopy (SEM) and RT-qPCR for viral RNA level. Long-term infection induced progressive mitochondrial fragmentation and sustained ROS overproduction. Permeability to 70 kDa dextran increased significantly at 48 h post-infection and exceeded control levels threefold by 168 h. SEM revealed gradual endothelial surface roughening, blebbing, and eventual monolayer collapse with extensive intercellular gaps by week 12. Our study demonstrates that long-term MHV-JHM infection profoundly alters brain endothelial cell structure and function, triggering a cascade of changes that culminate in the disintegration of the BBB model. Full article
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16 pages, 2917 KB  
Article
In Vitro Comparative Study on Oppositely Charged Donepezil-Loaded Intranasal Liposomes
by Elika Valehi, Gábor Katona, Dorina Gabriella Dobó and Ildikó Csóka
Pharmaceutics 2025, 17(10), 1250; https://doi.org/10.3390/pharmaceutics17101250 - 24 Sep 2025
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Abstract
Background/Objectives: Intranasal delivery is a promising approach for targeting the central nervous system (CNS); however, most of the drugs show poor permeability through the nasal mucosa. Nanocarriers such as liposomes can improve nasal drug absorption; however, the surface charge of liposomes has [...] Read more.
Background/Objectives: Intranasal delivery is a promising approach for targeting the central nervous system (CNS); however, most of the drugs show poor permeability through the nasal mucosa. Nanocarriers such as liposomes can improve nasal drug absorption; however, the surface charge of liposomes has a key role in the nasal mucosal uptake process. Therefore, the present study aimed to formulate and compare the intranasal applicability of oppositely charged liposomes loaded with donepezil hydrochloride (DPZ) as CNS-active model compound using two different charge inducers, the negatively charged dicethyl phosphate (DCP) and the positively charged stearylamine (SA). Methods: Liposomes were prepared with a fixed phosphatidylcholine (PC)/cholesterol (CH) 7:2 molar ratio, while the effect of DCP and SA was studied in a 0.5:2 molar ratio. The most important properties for intranasal administration were studied, e.g., colloidal parameters, drug release and permeability behavior, and mucoadhesion. Results: It has been revealed that the reduction in liposome vesicle size is directly proportional to the amount of DCP, while it is inversely proportional to the amount of SA. This was also supported by the drug release studies—the lower vesicle size resulted in faster drug release. Both charge inducers increased the drug encapsulation efficiency (~60–80%) through tighter packing or increased spacing of the lipid bilayer structure. DCP also improved the in vitro nasal permeability compared to the initial DPZ solution. The positively charged SA showed more remarkable mucoadhesive properties than DCP. Conclusions: We can conclude that both charge inducers can be useful for improving nasal absorption of liposomal carriers, DCP in higher (PC:CH:DCP 7:2:2), while SA in lower concentrations (PC:CH:SA 7:2:0.5). Full article
(This article belongs to the Special Issue Advances in Colloidal Drug Delivery Systems)
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