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Search Results (601)

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Keywords = solute infiltration

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15 pages, 1077 KiB  
Article
Quantifying Groundwater Infiltration into Sewers with Chemical Markers Measurements and Bayesian Chemical Mass Balance Model: Methodology and Verification
by Pengfei Shen, Zixuan Zhang, Xiang Li, Mingyan Liu, Xufang Li, Qianqian Tu and Hailong Yin
Water 2025, 17(17), 2509; https://doi.org/10.3390/w17172509 - 22 Aug 2025
Abstract
Urban sewer conditions assessment is important for the proper conveyance of sanitary water to wastewater treatment plants prior to environmental discharge. An effective approach to address this important process needs to be developed. This paper presents a data-driven methodology for sewer condition assessment [...] Read more.
Urban sewer conditions assessment is important for the proper conveyance of sanitary water to wastewater treatment plants prior to environmental discharge. An effective approach to address this important process needs to be developed. This paper presents a data-driven methodology for sewer condition assessment with gridding-based chemical markers measurement in combination with a Bayesian chemical mass balance (CMB) model. A field study was performed in an urban sewer in Nanjing, China, to test the robustness of the developed methodology. In this site, data library of chemical markers (total nitrogen, phosphate, chloride, and total hardness) for source flows, including domestic wastewater, commercial wastewater and groundwater, was established. Meanwhile, a gridding-based measurement of these chemical markers in sewer flows was performed along the assessed sewer. Then, the CMB model with Bayesian inference and parallel Markov Chain Monte Carlo simulations was developed to quantify source contributions in sewer flows based on the chemical markers data of source and sewer flows. Accordingly, the proportion of clean water infiltration into the sewer and associated sewer defect level can be assessed. The Bayesian CMB model presented that groundwater contributed 11~14% of the sewer flow, indicating a neglectable sewer defect condition. The sewer assessment result was further verified by on-site physical inspection with distributed temperature sensing of in-sewer flows, proving the reliability of the developed methodology. Using this data-driven approach, a preliminary screening of the high-risk sub-catchments with severe sewer defect levels can be made for the following targeted sewer defects locations, optimizing the labor-intensive, system-wide physical inspections. Therefore, the proposed approach offers a cost-effective solution for system-wide sewer inspections. Full article
(This article belongs to the Section Urban Water Management)
21 pages, 6478 KiB  
Article
Localized Combination Therapy Using Collagen–Hydroxyapatite Bone Grafts for Simultaneous Bone Cancer Inhibition and Tissue Regeneration
by Alina Florentina Vladu, Madalina Georgiana Albu Kaya, Anton Ficai, Denisa Ficai, Raluca Tutuianu, Ludmila Motelica, Vasile Adrian Surdu, Ovidiu-Cristian Oprea, Roxana Doina Truşcă and Irina Titorencu
Polymers 2025, 17(16), 2239; https://doi.org/10.3390/polym17162239 - 18 Aug 2025
Viewed by 379
Abstract
The global burden of cancer continues to grow, with bone cancer—though rare—posing serious challenges in terms of treatment and post-surgical reconstruction. Autologous bone grafting remains the gold standard, yet limitations such as donor site morbidity drive the search for alternative solutions. Tissue engineering, [...] Read more.
The global burden of cancer continues to grow, with bone cancer—though rare—posing serious challenges in terms of treatment and post-surgical reconstruction. Autologous bone grafting remains the gold standard, yet limitations such as donor site morbidity drive the search for alternative solutions. Tissue engineering, combining biomaterials and therapeutic agents, offers promising avenues. This study focuses on the development of multifunctional scaffolds based on collagen and hydroxyapatite obtained by the freeze-drying technique and incorporating both synthetic (doxorubicin) and natural (caffeic acid) compounds for osteosarcoma treatment. These scaffolds aim to combine tumor inhibition with bone regeneration, addressing the dual need for local drug delivery and structural repair in bone cancer therapy. The characterization of these composite materials revealed that a spongious structure with interconnected pores and a homogeneous pore distribution, with pore sizes between 20 and 250 μm suitable for osteoblasts infiltration. The Fourier transform infrared (FTIR) spectroscopy and thermogravimetric analysis-differential scanning calorimetry (TG-DSC) and X-ray diffraction (XRD) analyses confirmed the formation of hydroxyapatite inside the collagen matrix. LDH and XTT assays confirmed that the antitumoral scaffolds possess great potential for osteosarcoma treatment, showing that after 3 days of culturing, the extracts containing doxorubicin-7A, both alone and in combination with caffeic acid-9A, significantly reduced the viability of cell lines to below 7% and 20%, respectively. Full article
(This article belongs to the Special Issue Smart and Bio-Medical Polymers: 3rd Edition)
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16 pages, 20542 KiB  
Article
Establishment of Agrobacterium-Mediated Transient Transformation System in Sunflower
by Fangyuan Chen, Lai Wang, Qixiu Huang, Run Jiang, Wenhui Li, Xianfei Hou, Zihan Tan, Zhonghua Lei, Qiang Li and Youling Zeng
Plants 2025, 14(15), 2412; https://doi.org/10.3390/plants14152412 - 4 Aug 2025
Viewed by 420
Abstract
Sunflower (Helianthus annuus L.) is an important oilseed crop in Northwest China, exhibiting resistance to salt and drought. Mining its excellent tolerance genes can be used for breeding. However, the current platforms for identifying gene function in sunflower is inadequate. The transient [...] Read more.
Sunflower (Helianthus annuus L.) is an important oilseed crop in Northwest China, exhibiting resistance to salt and drought. Mining its excellent tolerance genes can be used for breeding. However, the current platforms for identifying gene function in sunflower is inadequate. The transient transformation system, which can rapidly validate gene function, shows promising prospects in research. In this study, we established an efficient transient expression transformation system for sunflower using three methods: Agrobacterium-mediated infiltration, injection, and ultrasonic-vacuum. The detailed procedures were as follows: Agrobacterium GV3101 carrying a GUS reporter gene on the pBI121 vector with an OD600 of 0.8 as the bacterial suspension and 0.02% Silwet L-77 as the surfactant were utilized in all three approaches. For the infiltration method, seedlings grown hydroponically for 3 days were immersed in a bacterial suspension containing 0.02% Silwet L-77 for 2 h; for the injection method, the same solution was injected into the cotyledons of seedlings grown in soil for 4 to 6 days. Subsequently, the seedlings were cultured in the dark at room temperature for three days; for the ultrasonic-vacuum method, seedlings cultured in Petri dishes for 3 days were first subjected to ultrasonication at 40 kHz for 1 min, followed by vacuum infiltration at 0.05 kPa for 5–10 min. Agrobacterium-mediated transient transformation efficiency achieved by the three methods exceeded 90%, with gene expression being sustained for at least 6 days. Next, we employed the infiltration-based sunflower transient transformation technology with the Arabidopsis stable transformation platform to confirm salt and drought stress tolerance of candidate gene HaNAC76 from sunflower responding to various abiotic stresses. Altogether, this study successfully established an Agrobacterium-mediated transient transformation system for sunflower using these three methods, which can rapidly identify gene function and explore the molecular mechanisms underlying sunflower’s resistance traits. Full article
(This article belongs to the Section Plant Cell Biology)
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14 pages, 2052 KiB  
Article
Study on the Shear Strength and Durability of Ionic Soil Stabilizer-Modified Soft Soil in Acid Alkali Environments
by Zhifeng Ren, Shijie Lin, Siyu Liu, Bo Li, Jiankun Liu, Liang Chen, Lideng Fan, Ziling Xie and Lingjie Wu
Eng 2025, 6(8), 178; https://doi.org/10.3390/eng6080178 - 1 Aug 2025
Viewed by 329
Abstract
Soft soils, characterized by high compressibility, low shear strength, and high water sensitivity, pose serious challenges to geotechnical engineering in infrastructure projects. Traditional stabilization methods such as lime and cement face limitations, including environmental concerns and poor durability under chemical or cyclic loading. [...] Read more.
Soft soils, characterized by high compressibility, low shear strength, and high water sensitivity, pose serious challenges to geotechnical engineering in infrastructure projects. Traditional stabilization methods such as lime and cement face limitations, including environmental concerns and poor durability under chemical or cyclic loading. Ionic soil stabilizers (ISSs), which operate through electrochemical mechanisms, offer a promising alternative. However, their long-term performance—particularly under environmental stressors such as acid/alkali exposure and cyclic wetting–drying—remains insufficiently explored. This study evaluates the strength and durability of ISS-modified soil through a comprehensive experimental program, including direct shear tests, permeability tests, and cyclic wetting–drying experiments under neutral, acidic (pH = 4), and alkaline (pH = 10) environments. The results demonstrate that ISS treatment increases soil cohesion by up to 75.24% and internal friction angle by 9.50%, particularly under lower moisture conditions (24%). Permeability decreased by 88.4% following stabilization, resulting in only a 10–15% strength loss after water infiltration, compared to 40–50% in untreated soils. Under three cycles of wetting–drying, ISS-treated soils retained high shear strength, especially under acidic conditions, where degradation was minimal. In contrast, alkaline conditions caused a cohesion reduction of approximately 26.53%. These findings confirm the efficacy of ISSs in significantly improving both the mechanical performance and environmental durability of soft soils, offering a sustainable and effective solution for soil stabilization in chemically aggressive environments. Full article
(This article belongs to the Section Chemical, Civil and Environmental Engineering)
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28 pages, 6803 KiB  
Article
Structural Heterogeneity of Biochar Modulates’ Soil Hydraulic Properties and Nutrient Migration
by Guohui Li, Yayong Chen, Xiaopeng Chen, Beibei Zhou, Manli Duan, Hongyan Zhu and Guomin Shao
Agronomy 2025, 15(8), 1830; https://doi.org/10.3390/agronomy15081830 - 28 Jul 2025
Viewed by 474
Abstract
Biochar application is a well-recognized strategy to enhance agricultural soil fertility, but its structural heterogeneity leads to inconsistent outcomes in soil improvement, particularly in water and nutrient transport dynamics. In order to ensure the beneficial effects of biochar-amended agricultural soils in terms of [...] Read more.
Biochar application is a well-recognized strategy to enhance agricultural soil fertility, but its structural heterogeneity leads to inconsistent outcomes in soil improvement, particularly in water and nutrient transport dynamics. In order to ensure the beneficial effects of biochar-amended agricultural soils in terms of water retention and fertilizer fixation, in this paper, we aim to elucidate the effect of the structural heterogeneity of biochar on the hydraulic properties and nutrient transport of agricultural soils. This study compares biochars at millimeter (BMP), micrometer (BUP), and nanometer (BNP) scales using CT scanning, and investigates the effects of different application rates (0.0–2.0%) on soil’s hydraulic properties and nutrient transport using soil column experiments and CDE analyses. The results show that biochar generally decreased soil saturated hydraulic conductivity (SSHC), except for the application of 2.0% BMP, which increased it. Biochar enhanced soil saturated water content (SSWC) and water holding capacity (WHC), with the 2.0% BMP treatment achieving the highest values (SSHC: 49.34 cm/d; SSWC: 0.40 g/g; WHC: 0.25 g/g). BUPs and BNPs inhibited water infiltration due to pore-blocking, while 2.0% BMP promoted infiltration. Convective dispersion equation analysis (CDE) indicated that BUPs and BNPs reduced water and nutrient transport, with 2.0% BMP showing optimal performance. Statistical analyses revealed that biochar’s structural heterogeneity significantly affected soil water repellency, its hydraulic properties, and solute transport (p < 0.05). Smaller particles enhanced water retention and nutrient fixation, while larger particles improved WHC at appropriate rates. These findings provide valuable insights for optimizing biochar application to improve soil functions and support sustainable agriculture. Full article
(This article belongs to the Section Soil and Plant Nutrition)
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14 pages, 2113 KiB  
Article
NR2F6 as a Disease Driver and Candidate Therapeutic Target in Experimental Cerebral Malaria
by Victoria E. Stefan, Victoria Klepsch, Nikolaus Thuille, Martina Steinlechner, Sebastian Peer, Kerstin Siegmund, Peter Lackner, Erich Schmutzhard, Karin Albrecht-Schgör and Gottfried Baier
Cells 2025, 14(15), 1162; https://doi.org/10.3390/cells14151162 - 28 Jul 2025
Viewed by 389
Abstract
Cerebral malaria (CM) is the severe progression of an infection with Plasmodium falciparum, causing detrimental damage to brain tissue and is the most frequent cause of Plasmodium falciparum mortality. The critical role of brain-infiltrating CD8+ T cells in the pathophysiology of [...] Read more.
Cerebral malaria (CM) is the severe progression of an infection with Plasmodium falciparum, causing detrimental damage to brain tissue and is the most frequent cause of Plasmodium falciparum mortality. The critical role of brain-infiltrating CD8+ T cells in the pathophysiology of CM having been revealed, our investigation focuses on the role of NR2F6, an established immune checkpoint, as a candidate driver of CM pathology. We employed an experimental mouse model of CM based on Plasmodium berghei ANKA (PbA) infection to compare the relative susceptibility of Nr2f6-knock-out and wild-type C57BL6/N mice. As a remarkable result, Nr2f6 deficiency confers a significant survival benefit. In terms of mechanism, we detected less severe endotheliopathy and, hence, less damage to the blood–brain barrier (BBB), accompanied by decreased sequestered parasites and less cytotoxic T-lymphocytes within the brain, manifesting in a better disease outcome. We present evidence that NR2F6 deficiency renders mice more resistant to experimental cerebral malaria (ECM), confirming a causal and non-redundant role for NR2F6 in the progression of ECM disease. Consequently, pharmacological inhibitors of the NR2F6 pathway could be of use to bolster BBB integrity and protect against CM. Full article
(This article belongs to the Section Cell Signaling)
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15 pages, 1388 KiB  
Article
SLC39A14 Is a Potential Therapy Target and Prognostic Biomarker for Acute Myeloid Leukemia
by Yun Li and Liming Shan
Genes 2025, 16(8), 887; https://doi.org/10.3390/genes16080887 - 27 Jul 2025
Viewed by 405
Abstract
Background: Programmed cell death-related genes (PCDRGs) have been reported to play an important role in diagnosis, treatment and immunity regarding cancer, but their prognostic value and therapeutic potential in acute myeloid leukemia (AML) patients still need to be fully explored. Methods: [...] Read more.
Background: Programmed cell death-related genes (PCDRGs) have been reported to play an important role in diagnosis, treatment and immunity regarding cancer, but their prognostic value and therapeutic potential in acute myeloid leukemia (AML) patients still need to be fully explored. Methods: Cox regression analysis and Least Absolute Shrinkage and Selection Operator (LASSO) analysis were used to identify PCDRGs significantly associated with the prognosis of AML patients. Furthermore, a prognostic risk model for AML patients was constructed based on the selected PCDRGs, and their immune microenvironment and biological pathways were analyzed. Cell experiments ultimately confirmed the potential role of PCDRGs in AML. Results: The results yielded four PCDRGs that were used to develop a prognostic risk model, and the prognostic significance of this model was confirmed using an independent external AML patient cohort. This prognostic risk model provides an independent prognostic risk factor for AML patients. This prognostic feature is related to immune cell infiltration in AML patients. The inhibition of solute carrier family 39 member 14 (SLC39A14) expression enhanced apoptosis and inhibited cell cycle progression in AML cells. Conclusions: This study integrates bioinformatics analysis and cellular experiments to reveal potential gene therapy targets and prognostic gene markers in AML. Full article
(This article belongs to the Section Molecular Genetics and Genomics)
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14 pages, 2459 KiB  
Article
Enhancement of Oral Mucosal Regeneration Using Human Exosomal Therapy in SD Rats
by Chien Ming Lee, Qasim Hussain, Kuo Pin Chuang and Hoang Minh
Biomedicines 2025, 13(7), 1785; https://doi.org/10.3390/biomedicines13071785 - 21 Jul 2025
Viewed by 750
Abstract
Background/Objectives: Oral cavity wound recovery presents unique challenges due to constant moisture exposure and functional mechanical stresses. Nanoscale extracellular vesicles (exosomes) with regenerative properties offer promising therapeutic potential for tissue regeneration, contributing to improved health outcomes. This study evaluated human exosomal preparations in [...] Read more.
Background/Objectives: Oral cavity wound recovery presents unique challenges due to constant moisture exposure and functional mechanical stresses. Nanoscale extracellular vesicles (exosomes) with regenerative properties offer promising therapeutic potential for tissue regeneration, contributing to improved health outcomes. This study evaluated human exosomal preparations in promoting oral mucosal regeneration. Methods: We established standardized full-thickness wounds in the buccal mucosa of SD rats and divided subjects into experimental (receiving 50 billion human exosomes) and control (receiving carrier solution only) groups. Comprehensive wound assessment occurred at predetermined intervals (days 0, 3, 7, and 10) through photographic documentation, histological examination, and quantitative measurement. Results: Exosomal-treated tissues demonstrated statistically significant acceleration in closure rates (p < 0.05), achieving 87.3% reduction by day 10 versus 64.1% in the controls. Microscopic analysis revealed superior epithelial development, reduced inflammatory infiltration, and enhanced collagen architectural organization in exosomal-treated specimens. Semi-quantitative evaluation confirmed consistently superior healing metrics in the experimental group across all assessment timepoints. Conclusions: These findings demonstrate that human exosome preparations significantly enhance oral mucosal regeneration in SD rats, suggesting potential clinical applications for accelerating recovery following oral surgical procedures. Full article
(This article belongs to the Section Molecular and Translational Medicine)
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23 pages, 5743 KiB  
Article
Impact of Low-Pressure in High-Altitude Area on the Aging Characteristics of NCM523/Graphite Pouch Cells
by Xiantao Chen, Zhi Wang, Jian Wang, Yichao Lin and Jian Li
Batteries 2025, 11(7), 261; https://doi.org/10.3390/batteries11070261 - 13 Jul 2025
Viewed by 512
Abstract
With the development and application of electric vehicles powered by lithium-ion batteries (LIBs) at high altitude, the lack of research on the aging laws and mechanisms of LIBs under a low-pressure aviation environment has become an important obstacle to their safe application. Herein, [...] Read more.
With the development and application of electric vehicles powered by lithium-ion batteries (LIBs) at high altitude, the lack of research on the aging laws and mechanisms of LIBs under a low-pressure aviation environment has become an important obstacle to their safe application. Herein, the influences and mechanisms of high-altitude and low-pressure environment (50 kPa) on the cycling performance of commercial pouch LIBs were systematically studied. The results showed that low air pressure caused a sharp decrease in battery capacity to 46.6% after 200 cycles, with a significant increase in charge transfer impedance by 70%, and the contribution rate of active lithium loss reached 74%. Low air pressure led to irreversible deformation of the battery, resulting in the expansion of the gap between the electrodes, poor electrolyte infiltration, and reduction of the effective lithium insertion area, which in turn induced multiple synergistic accelerated decay mechanisms, including obstructed lithium-ion transmission, reduced interfacial reaction efficiency, increased active lithium consumption, changes in heat generation structure, and a significant increase in heat generation. After applying external force, the deformation of the electrode was effectively suppressed, and the cycle capacity retention rate increased to 87.6%, which significantly alleviated the performance degradation of LIBs in low pressure environment. This work provides a key theoretical basis and engineering solutions for the design of power batteries in high-altitude areas. Full article
(This article belongs to the Special Issue Advances in Lithium-Ion Battery Safety and Fire: 2nd Edition)
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20 pages, 6872 KiB  
Article
The Simulation of Grouting Behavior in the Pea Gravel Filling Layer Behind a Double-Shield TBM Based on the Level Set Method
by Xinlong Li, Yulong Zhang, Dongjiao Cao, Yang Liu and Lin Chen
Appl. Sci. 2025, 15(13), 7542; https://doi.org/10.3390/app15137542 - 4 Jul 2025
Viewed by 330
Abstract
In double-shield TBM tunnel construction, grouting plays a vital role in consolidating the gravel backfill and maintaining the integrity of the segmental lining. To investigate the permeation behavior of grout within the pea gravel layer, a fluid dynamics model was developed in this [...] Read more.
In double-shield TBM tunnel construction, grouting plays a vital role in consolidating the gravel backfill and maintaining the integrity of the segmental lining. To investigate the permeation behavior of grout within the pea gravel layer, a fluid dynamics model was developed in this study. The model directly simulates the flow of grout through the porous medium by solving the Navier–Stokes equations and employs the level set method to track the evolving interface between the grout and air phases. Unlike conventional continuum approaches, this model incorporates particle-scale heterogeneity, allowing for a more realistic analysis of grout infiltration through the non-uniform pore structures formed by gravel packing. Three different grouting port positions and two boundary conditions are considered in the simulation. The results indicate that under pressure boundary conditions, the grout flow rate increases rapidly in the initial stage, and then decreases and stabilizes, with the flow rate peak increasing as the grout port moves upward. Under velocity boundary conditions, the injection pressure grows slowly in the early stage but accelerates with time. Additionally, the rate of pressure change is faster when the grout port is located lower in the backfilling layer. Through theoretical analysis, the existing analytical formula was extended by introducing a gravitational correction term. When the grouting port is near the upper part of the tunnel, the analytical solution aligns well with the numerical simulation results, but as the grout port moves downward, the discrepancy between the two increases. Full article
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19 pages, 6342 KiB  
Article
Innovative Use of UHPC and Topology Optimization in Permeable Interlocking Pavers: Advancing Sustainable Pavement Solutions
by Fernanda Gadler, José Augusto Ferreira Sales de Mesquita, Francisco Helio Alencar Oliveira, Liedi Legi Bariani Bernucci, Rafael Giuliano Pileggi, Emilio Carlos Nelli Silva and Diego Silva Prado
Sustainability 2025, 17(13), 6039; https://doi.org/10.3390/su17136039 - 1 Jul 2025
Viewed by 473
Abstract
The rapid expansion of urban areas has increased the prevalence of impermeable surfaces, intensifying flooding risks by disrupting natural water infiltration. Permeable pavements have emerged as a sustainable alternative, capable of reducing stormwater runoff, improving surface friction, and mitigating urban heat island effects. [...] Read more.
The rapid expansion of urban areas has increased the prevalence of impermeable surfaces, intensifying flooding risks by disrupting natural water infiltration. Permeable pavements have emerged as a sustainable alternative, capable of reducing stormwater runoff, improving surface friction, and mitigating urban heat island effects. Nevertheless, their broader implementation is often hindered by issues such as clogging and limited mechanical strength resulting from high porosity. This study examines the design of interlocking permeable blocks utilizing ultra-high-performance concrete (UHPC) to strike a balance between enhanced drainage capacity and high structural performance. A topology optimization (TO) strategy was applied to numerically model the ideal block geometry, incorporating 105 drainage channels with a diameter of 6 mm—chosen to ensure manufacturability and structural integrity. The UHPC formulation was developed using particle packing optimization with ordinary Portland cement (OPC), silica fume, and limestone filler to reduce binder content while achieving superior strength and workability, guided by rheological assessments. Experimental tests revealed that the perforated UHPC blocks reached compressive strengths of 87.8 MPa at 7 days and 101.0 MPa at 28 days, whereas the solid UHPC blocks achieved compressive strengths of 125.8 MPa and 146.2 MPa, respectively. In contrast, commercial permeable concrete blocks reached only 28.9 MPa at 28 days. Despite a reduction of approximately 30.9% in strength due to perforations, the UHPC-105holes blocks still far exceed the 41 MPa threshold required for certain structural applications. These results highlight the mechanical superiority of the UHPC blocks and confirm their viability for structural use even with enhanced permeability features. The present research emphasizes mechanical and structural performance, while future work will address hydraulic conductivity and anticlogging behavior. Overall, the findings support the use of topology-optimized UHPC permeable blocks as a resilient solution for sustainable urban drainage systems, combining durability, strength, and environmental performance. Full article
(This article belongs to the Special Issue Green Infrastructure and Sustainable Stormwater Management)
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16 pages, 1877 KiB  
Review
Capillary Rise and Salt Weathering in Spain: Impacts on the Degradation of Calcareous Materials in Historic Monuments
by Elías Afif-Khouri, Alfonso Lozano-Martínez, José Ignacio López de Rego, Belén López-Gallego and Rubén Forjan-Castro
Buildings 2025, 15(13), 2285; https://doi.org/10.3390/buildings15132285 - 29 Jun 2025
Viewed by 856
Abstract
The crystallization of soluble salts is one of the most significant agents of deterioration affecting porous building materials in historical architecture. This process not only compromises the physical integrity of the materials but also results in considerable aesthetic, structural, and economic consequences. Soluble [...] Read more.
The crystallization of soluble salts is one of the most significant agents of deterioration affecting porous building materials in historical architecture. This process not only compromises the physical integrity of the materials but also results in considerable aesthetic, structural, and economic consequences. Soluble salts involved in these processes may originate from geogenic sources—including soil leachate, marine aerosols, and the natural weathering of parent rocks—or from anthropogenic factors such as air pollution, wastewater infiltration, and the use of incompatible restoration materials. This study examines the role of capillary rise as a primary mechanism responsible for the vertical migration of saline solutions from the soil profile into historic masonry structures, especially those constructed with calcareous stones. It describes how water retained or sustained within the soil matrix ascends via capillarity, carrying dissolved salts that eventually crystallize within the pore network of the stone. This phenomenon leads to a variety of damage types, ranging from superficial staining and efflorescence to more severe forms such as subflorescence, microfracturing, and progressive mass loss. By adopting a multidisciplinary approach that integrates concepts and methods from soil physics, hydrology, petrophysics, and conservation science, this paper examines the mechanisms that govern saline water movement, salt precipitation patterns, and their cumulative effects on stone durability. It highlights the influence of key variables such as soil texture and structure, matric potential, hydraulic conductivity, climatic conditions, and stone porosity on the severity and progression of deterioration. This paper also addresses regional considerations by focusing on the context of Spain, which holds one of the highest concentrations of World Heritage Sites globally and where many monuments are constructed from vulnerable calcareous materials such as fossiliferous calcarenites and marly limestones. Special attention is given to the types of salts most commonly encountered in Spanish soils—particularly chlorides and sulfates—and their thermodynamic behavior under fluctuating environmental conditions. Ultimately, this study underscores the pressing need for integrated, preventive conservation strategies. These include the implementation of drainage systems, capillary barriers, and the use of compatible materials in restoration, as well as the application of non-destructive diagnostic techniques such as electrical resistivity tomography and hyperspectral imaging. Understanding the interplay between soil moisture dynamics, salt crystallization, and material degradation is essential for safeguarding the cultural and structural value of historic buildings in the face of ongoing environmental challenges and climate variability. Full article
(This article belongs to the Special Issue Selected Papers from the REHABEND 2024 Congress)
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22 pages, 13795 KiB  
Article
The Nucleation and Degradation of Pothole Wetlands by Human-Driven Activities and Climate During the Quaternary in a Semi-Arid Region (Southern Iberian Peninsula)
by A. Jiménez-Bonilla, I. Expósito, F. Gázquez, J. L. Yanes and M. Rodríguez-Rodríguez
Geographies 2025, 5(3), 27; https://doi.org/10.3390/geographies5030027 - 24 Jun 2025
Viewed by 366
Abstract
In this study, we selected a series of pothole wetlands to investigate their nucleation, evolution, and recent anthropogenic degradation in the Alcores Depression (AD), southern Iberian Peninsula, where over 100 closed watersheds containing shallow, ephemeral water bodies up to 2 hm2 have [...] Read more.
In this study, we selected a series of pothole wetlands to investigate their nucleation, evolution, and recent anthropogenic degradation in the Alcores Depression (AD), southern Iberian Peninsula, where over 100 closed watersheds containing shallow, ephemeral water bodies up to 2 hm2 have been identified. We surveyed the regional geological framework, utilized digital elevation models (DEMs), orthophotos, and aerial images since 1956. Moreover, we analyzed precipitation and temperature data in Seville from 1900 to 2024, collected hydrometeorological data since 1990 and modelled the water level evolution from 2002 to 2025 in a representative pothole in the area. Our observations indicate a flooded surface reduction by more than 90% from the 1950s to 2025. Climatic data reveal an increase in annual mean temperatures since 1960 and a sharp decline in annual precipitation since 2000. The AD’s inception due to tectonic isolation during the Quaternary favoured the formation of pothole wetlands in the floodplain. The reduction in the hydroperiod and wetland degradation was primarily due to agricultural expansion since 1950, which followed an increase in groundwater extraction and altered the original topography. Recently, decreased precipitation has exponentially accelerated the degradation and even the complete disappearance of many potholes. This study underscores the fragility of small wetlands in the Mediterranean basin and the critical role of human management in their preservation. Restoring these ecosystems could be a highly effective nature-based solution, especially in semi-arid climates like southern Spain. These prairie potholes are crucial for enhancing groundwater recharge, which is vital for maintaining water availability in regions with limited precipitation. By facilitating rainwater infiltration into the aquifer, recharge potholes increase groundwater levels. Additionally, they capture and store run-off during heavy rainfall, reducing the risk of flooding and soil erosion. Beyond their hydrological functions, these wetlands provide habitats that support biodiversity and promote ecological resilience, reinforcing the need for their protection and recovery. Full article
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40 pages, 5193 KiB  
Review
A Comprehensive Review of the Development of Perovskite Oxide Anodes for Fossil Fuel-Based Solid Oxide Fuel Cells (SOFCs): Prospects and Challenges
by Arash Yahyazadeh
Physchem 2025, 5(3), 25; https://doi.org/10.3390/physchem5030025 - 23 Jun 2025
Viewed by 968
Abstract
Solid oxide fuel cells (SOFCs) represent a pivotal technology in renewable energy due to their clean and efficient power generation capabilities. Their role in potential carbon mitigation enhances their viability. SOFCs can operate via a variety of alternative fuels, including hydrocarbons, alcohols, solid [...] Read more.
Solid oxide fuel cells (SOFCs) represent a pivotal technology in renewable energy due to their clean and efficient power generation capabilities. Their role in potential carbon mitigation enhances their viability. SOFCs can operate via a variety of alternative fuels, including hydrocarbons, alcohols, solid carbon, and ammonia. However, several solutions have been proposed to overcome various technical issues and to allow for stable operation in dry methane, without coking in the anode layer. To avoid coke formation thermodynamically, methane is typically reformed, contributing to an increased degradation rate through the addition of oxygen-containing gases into the fuel gas to increase the O/C ratio. The performance achieved by reforming catalytic materials, comprising active sites, supports, and electrochemical testing, significantly influences catalyst performance, showing relatively high open-circuit voltages and coking-resistance of the CH4 reforming catalysts. In the next step, the operating principles and thermodynamics of methane reforming are explored, including their traditional catalyst materials and their accompanying challenges. This work explores the components and functions of SOFCs, particularly focusing on anode materials such as perovskites, Ruddlesden–Popper oxides, and spinels, along with their structure–property relationships, including their ionic and electronic conductivity, thermal expansion coefficients, and acidity/basicity. Mechanistic and kinetic studies of common reforming processes, including steam reforming, partial oxidation, CO2 reforming, and the mixed steam and dry reforming of methane, are analyzed. Furthermore, this review examines catalyst deactivation mechanisms, specifically carbon and metal sulfide formation, and the performance of methane reforming and partial oxidation catalysts in SOFCs. Single-cell performance, including that of various perovskite and related oxides, activity/stability enhancement by infiltration, and the simulation and modeling of electrochemical performance, is discussed. This review also addresses research challenges in regards to methane reforming and partial oxidation within SOFCs, such as gas composition changes and large thermal gradients in stack systems. Finally, this review investigates the modeling of catalytic and non-catalytic processes using different dimension and segment simulations of steam methane reforming, presenting new engineering designs, material developments, and the latest knowledge to guide the development of and the driving force behind an oxygen concentration gradient through the external circuit to the cathode. Full article
(This article belongs to the Section Electrochemistry)
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9 pages, 1926 KiB  
Communication
Surface Modification of Fe-Based Perovskite Oxide via Sr0.95Ce0.05CoO3−δ Infiltration: A Strategy for Thermochemical Stability
by Taeheun Lim and Heesoo Lee
Nanomaterials 2025, 15(12), 934; https://doi.org/10.3390/nano15120934 - 16 Jun 2025
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Abstract
Cobalt-based perovskite oxides exhibit remarkable catalytic activity owing to abundant oxygen vacancies and mixed ionic–electronic conductivity, but they suffer from structural instability. In contrast, iron-based perovskite oxides are thermochemically stable under oxidizing and reducing conditions but are catalytically limited. To combine these complementary [...] Read more.
Cobalt-based perovskite oxides exhibit remarkable catalytic activity owing to abundant oxygen vacancies and mixed ionic–electronic conductivity, but they suffer from structural instability. In contrast, iron-based perovskite oxides are thermochemically stable under oxidizing and reducing conditions but are catalytically limited. To combine these complementary properties, a composite perovskite oxide was designed and prepared by infiltrating Sr0.95Ce0.05CoO3−δ (SCC) into Ba0.5Sr0.5Fe0.8Cu0.2O3−δ (BSFC). The SCC precursor solution was dropwise applied to a BSFC|SDC|BSFC symmetric cell and heat treated. Surface morphology and compositional analyses confirmed the distribution of SCC nanoparticles on the BSFC surface. High-temperature X-ray diffraction and Rietveld refinement results revealed that both BSFC and SCC retained the cubic perovskite structure (space group Pm-3m) at room temperature. No phase transition or secondary phase formation was observed during heating from 200 to 800 °C, and the peak shifts are attributed to thermal expansion and possible oxygen loss at elevated temperatures. Upon cooling, the diffraction patterns returned to their initial state, confirming a high-temperature structural stability. XPS analysis showed an increase in the satellite peak intensity associated with Fe3+ after SCC infiltration, and the average oxidation state of Fe decreased from 3.52 (BSFC) to 3.49 (composite perovskite oxide). The O 1s spectra revealed a higher relative content of surface-adsorbed oxygen species in the composite, indicating increased oxygen vacancy formation. Full article
(This article belongs to the Section Nanocomposite Materials)
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