Sign in to use this feature.

Years

Between: -

Subjects

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Journals

remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline
remove_circle_outline

Article Types

Countries / Regions

remove_circle_outline
remove_circle_outline
remove_circle_outline

Search Results (391)

Search Parameters:
Keywords = photo protectants

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
20 pages, 3293 KiB  
Article
Does Beach Sand Nourishment Have a Negative Effect on Natural Recovery of a Posidonia oceanica Seagrass Fringing Reef? The Case of La Vieille Beach (Saint-Mandrier-sur-Mer) in the North-Western Mediterranean
by Dominique Calmet, Pierre Calmet and Charles-François Boudouresque
Water 2025, 17(15), 2287; https://doi.org/10.3390/w17152287 - 1 Aug 2025
Viewed by 307
Abstract
Posidonia oceanica seagrass, endemic to the Mediterranean Sea, provides ecological goods and ecosystem services of paramount importance. In shallow and sheltered bays, P. oceanica meadows can reach the sea surface, with leaf tips slightly emerging, forming fringing and barrier reefs. During the 20th [...] Read more.
Posidonia oceanica seagrass, endemic to the Mediterranean Sea, provides ecological goods and ecosystem services of paramount importance. In shallow and sheltered bays, P. oceanica meadows can reach the sea surface, with leaf tips slightly emerging, forming fringing and barrier reefs. During the 20th century, P. oceanica declined conspicuously in the vicinity of large ports and urbanized areas, particularly in the north-western Mediterranean. The main causes of decline are land reclamation, anchoring, bottom trawling, turbidity and pollution. Artificial sand nourishment of beaches has also been called into question, with sand flowing into the sea, burying and destroying neighbouring meadows. A fringing reef of P. oceanica, located at Saint-Mandrier-sur-Mer, near the port of Toulon (Provence, France), is severely degraded. Analysis of aerial photos shows that, since the beginning of the 2000s, it has remained stable in some parts or continued to decline in others. This contrasts with the trend towards recovery, observed in France, thanks to e.g., the legally protected status of P. oceanica, and the reduction of pollution and coastal developments. The sand nourishment of the study beach, renewed every year, with the sand being washed or blown very quickly (within a few months) from the beach into the sea, burying the P. oceanica meadow, seems the most likely explanation. Other factors, such as pollution, trampling by beachgoers and overgrazing, may also play a role in the decline. Full article
(This article belongs to the Section Oceans and Coastal Zones)
Show Figures

Figure 1

18 pages, 4624 KiB  
Article
Andrographis paniculata Extract Supports Skin Homeostasis by Enhancing Epidermal Stem Cell Function and Reinforcing Their Extracellular Niche
by Roberta Lotti, Laetitia Cattuzzato, Xuefeng Huang, David Garandeau, Elisabetta Palazzo, Marika Quadri, Cécile Delluc, Eddy Magdeleine, Xiaojing Li, Mathilde Frechet and Alessandra Marconi
Cells 2025, 14(15), 1176; https://doi.org/10.3390/cells14151176 - 30 Jul 2025
Viewed by 424
Abstract
Skin aging is characterized by compromised epidermal homeostasis and dermo-epidermal junction (DEJ) integrity, resulting in reduced stem cell potential and impaired tissue regeneration. This study investigated the effects of Andrographis paniculata extract (APE) on keratinocyte stem cells (KSCs) and DEJ composition in human [...] Read more.
Skin aging is characterized by compromised epidermal homeostasis and dermo-epidermal junction (DEJ) integrity, resulting in reduced stem cell potential and impaired tissue regeneration. This study investigated the effects of Andrographis paniculata extract (APE) on keratinocyte stem cells (KSCs) and DEJ composition in human skin. Using human skin explants and cell culture models, we demonstrated that APE treatment enhances DEJ composition by increasing Collagen IV and Laminin production while decreasing MMP-9 expression, without altering epidermal structure or differentiation. In the same model, APE preserved stemness potential by upregulating markers related to niche components (collagen XVII and β1-integrin), proliferation (Ki-67 and KRT15), and stem cell capacity (Survivin and LRIG1). In vitro studies revealed that APE selectively stimulated KSC proliferation without affecting transit amplifying cells and promoted Collagen IV and Laminin secretion, particularly in KSCs. Furthermore, in a co-culture model simulating a compromised DEJ (UVB-induced), APE increased Laminin production in KSCs, suggesting a protective effect against photo-damage. These findings indicate that APE enhances DEJ composition and preserves stem cell potential, highlighting its promise as a candidate for skin anti-aging strategies targeting stem cell maintenance and extracellular matrix stability to promote skin regeneration and repair. Full article
Show Figures

Graphical abstract

17 pages, 7301 KiB  
Article
Environmental Analysis for the Implementation of Underwater Paths on Sepultura Beach, Southern Brazil: The Case of Palythoa caribaeorum Bleaching Events at the Global Southern Limit of Species Distribution
by Rafael Schroeder, Lucas Gavazzoni, Carlos E. N. de Oliveira, Pedro H. M. L. Marques and Ewerton Wegner
Coasts 2025, 5(3), 26; https://doi.org/10.3390/coasts5030026 - 28 Jul 2025
Viewed by 205
Abstract
Recreational diving depends on healthy marine ecosystems, yet it can harm biodiversity through species displacement and habitat damage. Bombinhas, a biodiverse diving hotspot in southern Brazil, faces growing threats from human activity and climate change. This study assessed the ecological structure of Sepultura [...] Read more.
Recreational diving depends on healthy marine ecosystems, yet it can harm biodiversity through species displacement and habitat damage. Bombinhas, a biodiverse diving hotspot in southern Brazil, faces growing threats from human activity and climate change. This study assessed the ecological structure of Sepultura Beach (2018) for potential diving trails, comparing it with historical data from Porto Belo Island. Using visual censuses, transects, and photo-quadrats across six sampling campaigns, researchers documented 2419 organisms from five zoological groups, identifying 14 dominant species, including Haemulon aurolineatum and Diplodus argenteus. Cluster analysis revealed three ecological zones, with higher biodiversity at the site’s edges (Groups 1 and 3), but these areas also hosted endangered species like Epinephelus marginatus, complicating trail planning. A major concern was the widespread bleaching of the zoanthid Palythoa caribaeorum, a key ecosystem engineer, likely due to rising sea temperatures (+1.68 °C from 1961–2018) and declining chlorophyll-a levels post-2015. Comparisons with past data showed a 0.33 °C increase in species’ thermal preferences over 17 years, alongside lower trophic levels and greater ecological vulnerability, indicating tropicalization from the expanding Brazil Current. While Sepultura Beach’s biodiversity supports diving tourism, conservation efforts must address coral bleaching and endangered species protection. Long-term monitoring is crucial to track warming impacts, and adaptive management is needed for sustainable trail development. The study highlights the urgent need to balance ecotourism with climate resilience in subtropical marine ecosystems. Full article
Show Figures

Figure 1

29 pages, 42729 KiB  
Article
Sustainable and Functional Polymeric Coating for Wood Preservation
by Ramona Marina Grigorescu, Rodica-Mariana Ion, Lorena Iancu, Sofia Slamnoiu-Teodorescu, Anca Irina Gheboianu, Elvira Alexandrescu, Madalina Elena David, Mariana Constantin, Iuliana Raut, Celina Maria Damian, Cristian-Andi Nicolae and Bogdan Trica
Coatings 2025, 15(8), 875; https://doi.org/10.3390/coatings15080875 - 25 Jul 2025
Viewed by 345
Abstract
The development of sustainable and functional nanocomposites has attracted considerable attention in recent years due to their broad spectrum of potential applications, including wood preservation. Also, a global goal is to reuse the large volumes of waste for environmental issues. In this context, [...] Read more.
The development of sustainable and functional nanocomposites has attracted considerable attention in recent years due to their broad spectrum of potential applications, including wood preservation. Also, a global goal is to reuse the large volumes of waste for environmental issues. In this context, the aim of the study was to obtain soda lignin particles, to graft ZnO nanoparticles onto their surface and to apply these hybrids, embedded into a biodegradable polymer matrix, as protection/preservation coating for oak wood. The organic–inorganic hybrids were characterized in terms of compositional, structural, thermal, and morphological properties that confirm the efficacy of soda lignin extraction and ZnO grafting by physical adsorption onto the decorating support and by weak interactions and coordination bonding between the components. The developed solution based on poly(3-hydroxybutyrate-co-3-hydroxyvalerate) and lignin-ZnO was applied to oak wood specimens by brushing, and the improvement in hydrophobicity (evaluated by water absorption that decreased by 48.8% more than wood, humidity tests where the treated sample had a humidity of 4.734% in comparison with 34.911% for control, and contact angle of 97.8° vs. 80.5° for untreated wood) and UV and fungal attack protection, while maintaining the color and aspect of specimens, was sustained. L.ZnO are well dispersed into the polymer matrix, ensuring a smooth and less porous wood surface. According to the results, the obtained wood coating using both a biodegradable polymeric matrix and a waste-based preservative can be applied for protection against weathering degradation factors, with limited water uptake and swelling of the wood, UV shielding, reduced wood discoloration and photo-degradation, effective protection against fungi, and esthetic quality. Full article
Show Figures

Figure 1

22 pages, 2603 KiB  
Review
Core–Shell Engineering of One-Dimensional Cadmium Sulfide for Solar Energy Conversion
by Rama Krishna Chava and Misook Kang
Nanomaterials 2025, 15(13), 1000; https://doi.org/10.3390/nano15131000 - 27 Jun 2025
Viewed by 387
Abstract
Fabricating efficient photocatalysts that can be used in solar-to-fuel conversion and to enhance the photochemical reaction rate is essential to the current energy crisis and climate changes due to the excessive usage of nonrenewable fossil fuels. To attain high photo-to-chemical conversion efficiency, it [...] Read more.
Fabricating efficient photocatalysts that can be used in solar-to-fuel conversion and to enhance the photochemical reaction rate is essential to the current energy crisis and climate changes due to the excessive usage of nonrenewable fossil fuels. To attain high photo-to-chemical conversion efficiency, it is important to fabricate cost-effective and durable catalysts with high activity. One-dimensional cadmium sulfides (1D CdS), with higher surface area, charge carrier separation along the linear direction, and visible light harvesting properties, are promising candidates for converting solar energy to H2, reducing CO2 to commodity chemicals, and remediating environmental pollutants. The main disadvantage of CdS is photocorrosion due to the leaching of S2− ions during the photochemical reactions, and further charge recombination rate leads to low quantum efficiency. Therefore, the implementation of core–shell heterostructured morphology, i.e., the growth of the shell on the surface of the 1D CdS, which offers unique features such as protection of CdS from photocorrosion, a tunable interface between the core CdS and shell, and photogenerated charge carrier separation via heterojunctions, provides additional active sites and enhanced visible light harvesting. Therefore, the viability of the core–shell synthesis strategy and synergetic effects offer a new way of designing photocatalysts with enhanced stability and improved charge separation in solar energy conversion systems. This review highlights some critical aspects of synthesizing 1D CdS core–shell heterostructures, underlying reaction mechanisms, and their performance in photoredox reactions. Finally, some challenges and considerations in the fabrication of 1D CdS-based core–shell nanostructures that can overcome the current barriers in industrial applications are discussed. Full article
Show Figures

Figure 1

35 pages, 5123 KiB  
Review
Prebiotic Oligosaccharides in Skin Health: Benefits, Mechanisms, and Cosmetic Applications
by Meijun Zeng, Yang Li, Jie Cheng, Jingyu Wang and Qiyu Liu
Antioxidants 2025, 14(6), 754; https://doi.org/10.3390/antiox14060754 - 18 Jun 2025
Cited by 2 | Viewed by 1385
Abstract
Prebiotic oligosaccharides have attracted significant interest in dermatology and skin health due to their ability to modulate the skin microbiome and microbiota–host interactions. This review offers a novel dual perspective, systematically examining the benefits of both oral intake and topical application of prebiotic [...] Read more.
Prebiotic oligosaccharides have attracted significant interest in dermatology and skin health due to their ability to modulate the skin microbiome and microbiota–host interactions. This review offers a novel dual perspective, systematically examining the benefits of both oral intake and topical application of prebiotic oligosaccharides, including well-established prebiotics (e.g., human milk oligosaccharides, galacto- and fructo-oligosaccharides) and emerging prebiotic candidates (e.g., gluco-oligosaccharides, chitosan-oligosaccharides, agaro-oligosaccharides). First, cutting-edge synthetic processes for producing diverse oligosaccharides and their structural chemistry are introduced. Then, we discuss in vitro studies demonstrating their efficacy in promoting skin commensals, inhibiting pathogens, and conferring protective effects, such as antioxidant, anti-inflammatory, anti-melanogenic, and wound-healing properties. Furthermore, we emphasize in vivo animal studies and clinical trials revealing that prebiotic oligosaccharides, administered orally or topically, alleviate atopic dermatitis, enhance skin hydration, attenuate acne, and protect against photo-aging by modulating skin–gut microbiota and immune responses. Mechanistically, we integrate genetic and molecular insights to elucidate how oligosaccharides mediate these benefits, including gut–skin axis crosstalk, immune regulation, and microbial metabolite signaling. Finally, we highlight current commercial applications of oligosaccharides in cosmetic formulations while addressing scientific and practical challenges, such as structure–function relationships, clinical scalability, and regulatory considerations. This review bridges mechanistic understanding with practical applications, offering a comprehensive resource for advancing prebiotic oligosaccharides-based skincare therapies. Full article
Show Figures

Figure 1

18 pages, 2909 KiB  
Article
Characterization of a Supersonic Plasma Jet by Means of Optical Emission Spectroscopy
by Ruggero Barni, Hanaa Zaka, Dipak Pal, Irsa Amjad and Claudia Riccardi
Photonics 2025, 12(6), 595; https://doi.org/10.3390/photonics12060595 - 10 Jun 2025
Viewed by 961
Abstract
We discuss an innovative thin film deposition method, Plasma Assisted Supersonic Jet Deposition, which combines the chemistry richness of a reactive cold plasma environment and the assembly control of the film growth allowed by a supersonic jet directed at the substrate. Optical Emission [...] Read more.
We discuss an innovative thin film deposition method, Plasma Assisted Supersonic Jet Deposition, which combines the chemistry richness of a reactive cold plasma environment and the assembly control of the film growth allowed by a supersonic jet directed at the substrate. Optical Emission Spectroscopy was used to characterize the plasma state and the supersonic jet, together with its interaction with the substrate. We obtained several results in the deposition of silicon oxide thin films from Hexamethyldisiloxane, with different degrees of organic groups retention. In particular we exploited the features of emission spectra to measure the plasma dissociation and oxidation degree of the organic groups, as a function of the jet parameters. If controlled growth is achieved, such films are nanostructured materials suitable for applications like catalysis, photo catalysis, energy conversion and storage, besides their traditional uses as a barrier or protective coatings. Full article
Show Figures

Figure 1

17 pages, 3068 KiB  
Article
Alginate Microencapsulation as a Tool to Improve Biostimulant Activity Against Water Deficits
by David Jiménez-Arias, Sarai Morales-Sierra, Ana L. García-García, Antonio J. Herrera, Rayco Pérez Schmeller, Emma Suárez, Álvaro Santana-Mayor, Patrícia Silva, João Paulo Borges and Miguel Â. A. Pinheiro de Carvalho
Polymers 2025, 17(12), 1617; https://doi.org/10.3390/polym17121617 - 10 Jun 2025
Viewed by 697
Abstract
Climate change is reducing agricultural productivity through altered weather patterns and extreme events, potentially decreasing yields by 10–25%. Biostimulants like pyroglutamic acid can enhance plant tolerance to water stress, but their rapid degradation in the soil limits effectiveness. Encapsulation in alginate matrices promises [...] Read more.
Climate change is reducing agricultural productivity through altered weather patterns and extreme events, potentially decreasing yields by 10–25%. Biostimulants like pyroglutamic acid can enhance plant tolerance to water stress, but their rapid degradation in the soil limits effectiveness. Encapsulation in alginate matrices promises to be a good solution, protecting the compound and enabling controlled release. This study reports, for the first time, that encapsulated pyroglutamic acid markedly enhances drought tolerance in tomato and maize plants. The encapsulation strategy reduces effective concentration by an order of magnitude while significantly improving water use efficiency, photo-synthetic performance, and overall stress resilience. These findings demonstrate that alginate-based encapsulation substantially increases biostimulant uptake and efficacy, providing a novel and efficient strategy to mitigate water stress in crops, with important implications for climate-resilient agriculture. Two encapsulation methods for generating the alginate microcapsules are compared: ionic gelation with Nisco® system and the electrospray technique. Full article
(This article belongs to the Section Polymer Applications)
Show Figures

Figure 1

18 pages, 1809 KiB  
Article
A Photo-Crosslinked Casein-Tannic Acid System for Enhanced Hair Protection: A Green Chemistry Approach
by Sujin Kyung, Won-Gun Koh and Hyun Jong Lee
Polymers 2025, 17(12), 1585; https://doi.org/10.3390/polym17121585 - 6 Jun 2025
Viewed by 894
Abstract
Hair is continuously exposed to various damaging factors in daily life, necessitating effective protective strategies that balance efficacy with environmental sustainability. In this study, we developed an environmentally friendly hair protective coating using casein proteins crosslinked with tannic acid via riboflavin phosphate-mediated photo-initiation. [...] Read more.
Hair is continuously exposed to various damaging factors in daily life, necessitating effective protective strategies that balance efficacy with environmental sustainability. In this study, we developed an environmentally friendly hair protective coating using casein proteins crosslinked with tannic acid via riboflavin phosphate-mediated photo-initiation. Casein solutions containing tannic acid (0.05% w/v) and riboflavin phosphate (0.01–0.1% w/v) were prepared and applied to virgin Asian hair, followed by blue light irradiation to initiate crosslinking. The coating formation mechanism was investigated through rheological characterization, which confirmed successful network formation with optimal mechanical stability at a 0.05% tannic acid concentration. Chemical analysis using FTIR spectroscopy revealed subtle but meaningful interactions between the coating components, while SEM analysis demonstrated the coating’s integration with the hair surface. Mechanical property evaluations showed that the photo-crosslinked coating significantly enhanced hair tensile strength by approximately 21% compared to untreated hair, while maintaining appropriate elasticity. Region-specific analysis of stress–strain behavior indicated that the coating extended the initial Hookean region while preserving natural resistance in the post-yield region, creating a balanced enhancement in mechanical properties. This approach offers a promising alternative to conventional hair treatments by utilizing natural, food-grade components and mild processing conditions, addressing growing demands for sustainable hair care solutions that effectively protect against daily damage. Full article
Show Figures

Figure 1

24 pages, 5386 KiB  
Article
Study of the Electrical Conduction Mechanism in Low-Frequency Field for CuMnO2 Crednerite-Type Materials Obtained by Microwave-Assisted Hydrothermal Synthesis
by Catalin N. Marin, Maria Poienar, Antoanetta Lungu, Cristian Casut, Paula Sfirloaga and Iosif Malaescu
Crystals 2025, 15(6), 497; https://doi.org/10.3390/cryst15060497 - 23 May 2025
Viewed by 362
Abstract
The electrical conductivity of nanocrystalline CuMnO2 samples, obtained by microwave-assisted hydrothermal synthesis (MWH), is studied by impedance spectroscopy over a frequency range of 30 Hz to 2 MHz and a temperature range from 30 to 120 °C. Three samples are prepared to [...] Read more.
The electrical conductivity of nanocrystalline CuMnO2 samples, obtained by microwave-assisted hydrothermal synthesis (MWH), is studied by impedance spectroscopy over a frequency range of 30 Hz to 2 MHz and a temperature range from 30 to 120 °C. Three samples are prepared to start from a mixture of sulphate reactants, at two synthesis temperatures and different reaction times (of applying microwaves): sample S1 at 80 °C for 5 min; sample S2 at 120 °C for 5 min and sample S3 at 120 °C for one hour. The static conductivity values, σDC of samples S2 and S3, are approximately equal but larger than those of sample S1. This result suggests that using MWH synthesis at 120 °C, with different reaction times (samples S2 and S3), is sufficient for microwaves to be applied for at least 5 min to obtain samples with similar electrical properties. The experimental data were analysed based on three theoretical models, demonstrating that the most appropriate theoretical model to explain the electrical conduction mechanism in the samples is Mott’s variable range hopping (VRH) model. Using this model, the activation energy of conduction, (EA,cond), the density of localized states near the Fermi level, N(EF), the hopping distance, Rh(T), the hopping energy, Wh(T) and the charge carrier mobility (μ) were determined for the first time, for microwave-assisted hydrothermally synthesized crednerite. Additionally, the band gap energy (Wm) and hopping frequency (ωh) were evaluated at various temperatures T. Understanding the electrical conduction mechanism in the polycrystalline CuMnO2 materials is important for their use in photo-electrochemical and photocatalytic applications, photovoltaic devices, and, more recently, in environmental protection. Full article
(This article belongs to the Section Inorganic Crystalline Materials)
Show Figures

Figure 1

20 pages, 69905 KiB  
Article
Lossless Thumbnail Preservation Encryption Based on Reversible Information Hiding
by Junlin Ouyang, Tingjian Shi and Ruijie Wang
Electronics 2025, 14(10), 2060; https://doi.org/10.3390/electronics14102060 - 19 May 2025
Viewed by 371
Abstract
With the proliferation of multi-camera smartphones, image generation has proliferated and cloud storage services have become the primary tool for storing and sharing photos. However, this also poses privacy and security risks. Traditional image encryption techniques, while protecting privacy, also lead to loss [...] Read more.
With the proliferation of multi-camera smartphones, image generation has proliferated and cloud storage services have become the primary tool for storing and sharing photos. However, this also poses privacy and security risks. Traditional image encryption techniques, while protecting privacy, also lead to loss of image availability in the cloud. To balance security and availability, TPE (Thumbnail Preserving Encryption) is proposed. However, the decryption effect of the existing schemes is generally unsatisfactory, and many existing schemes are unable to achieve perfect restoration in practical applications. Meanwhile, a few fully reversible schemes are limited by the proposed algorithms, which makes it difficult to be extended to a wider range of applications. To solve this contradiction, this paper proposes a TPE scheme based on reversible information hiding. Specifically, the scheme preserves the DC coefficients of the image during the encryption process and encrypts the AC coefficients to enhance the security of the image, thus obtaining the intermediate encrypted image. Then, the intermediate encrypted image is pre-decrypted, and the subtle error between the original image and the intermediate encrypted image is used as the compensation information. In order to achieve lossless decryption, we introduce the reversible information hiding technique to embed the compensation information into the intermediate image, and we finally obtain the encrypted image. This is also applicable to other high-quality TPE schemes and can provide ideas for their optimization direction. The experimental results show that this scheme not only achieves lossless decryption but also outperforms other TPE schemes in terms of visual effect, while the file extension size is kept at a low level. The research in this paper provides new ideas for balancing image privacy protection and usability, which has important theoretical and practical significance. Full article
Show Figures

Figure 1

30 pages, 29780 KiB  
Article
SEM Investigation of Failure Mechanisms in Twaron® Aramid Fibers Used for Personal Armors
by Alina Cantaragiu Ceoromila, Lorena Deleanu, Christian Popescu, Ionuț Lom, Alexandru Viorel Vasiliu, Petre Lucian Seiciu, George Ghiocel Ojoc and Simona Maria Sandu
Polymers 2025, 17(8), 1058; https://doi.org/10.3390/polym17081058 - 14 Apr 2025
Viewed by 793
Abstract
This paper presents a synthesis of failures of aramid fibers used in protective systems, with the help of SEM images obtained from three types of samples (panels made of fabrics with aramid fibers) tested against bullets, knives and spikes. This investigation is useful [...] Read more.
This paper presents a synthesis of failures of aramid fibers used in protective systems, with the help of SEM images obtained from three types of samples (panels made of fabrics with aramid fibers) tested against bullets, knives and spikes. This investigation is useful when using a step-by-step magnification and even macro photos in order to explain the mechanical failures of fibers. Several types of failure mechanisms (shear and tensile break, local bending, debonding from the matrix, fibrillation, local necking, etc.) were detected and discussed. Almost all of these failure mechanisms are present, with different densities of occurrence, in the studied panels made of aramid fibers. The description of failure mechanisms had to be conducted following the test conditions accurately. Failure mechanisms of aramid fibers are particularly relevant due to their specific molecular chains making them adequate for applications like ballistic and bladed weapon attacks. Full article
(This article belongs to the Section Polymer Analysis and Characterization)
Show Figures

Figure 1

16 pages, 8657 KiB  
Article
Impact of NaHCO3/Na2CO3 Buffer Reagent on Mitigating the Corrosion of C110 Steel in Water-Based Annulus Protection Fluid at Ultrahigh Temperature
by Zhi Zhang, Mifeng Zhao, Yan Li, Junfeng Xie, Wenwen Song, Juantao Zhang, Mengkai Wang, Jie Zhou, Yuan Wang, Xiaowei Lei and Danping Li
Materials 2025, 18(7), 1668; https://doi.org/10.3390/ma18071668 - 5 Apr 2025
Viewed by 705
Abstract
The drilling of ultradeep oil wells brings many challenges to the downhole tubular materials, where corrosion induced by halide annulus protection fluid is one major problem. In this work, the Na2CO3/NaHCO3 buffer system is employed to mitigate the [...] Read more.
The drilling of ultradeep oil wells brings many challenges to the downhole tubular materials, where corrosion induced by halide annulus protection fluid is one major problem. In this work, the Na2CO3/NaHCO3 buffer system is employed to mitigate the corrosion of C110 steel in NaBr annulus protection fluid at 220 °C. Weight loss tests, corrosion morphologies characterizations, and electrochemical measurements were used to investigate the inhibition effect. X-ray diffraction and X-ray photo-electron spectroscopy were employed to analyze the surface phase compositions. It is found that the Na2CO3/NaHCO3 buffer reagents effectively inhibit the corrosion of C110 steel, and the inhibition efficiency can reach 96.1%. The higher pH leads to the better inhibition performance, and, particularly, the buffer system is more effective in the corrosion environment of greater aggressivity. Without buffer reagents, the steel substrate is subjected to higher degree of uniform etching and pitting corrosion due to the formation of loose and porous corrosion products. In contrast, the addition of buffer reagents facilitates the formation of thinner but denser and more protective Fe3O4 passive film, contributing the high corrosion inhibition efficiency. Our work paves the way for the safe service of NaBr annulus protection fluid at 220 °C in ultradeep oil wells. Full article
(This article belongs to the Special Issue Advances in Corrosion and Protection of Metallic Materials)
Show Figures

Figure 1

27 pages, 4252 KiB  
Article
Facial Privacy Protection with Dynamic Multi-User Access Control for Online Photo Platforms
by Andri Santoso, Samsul Huda, Yuta Kodera and Yasuyuki Nogami
Future Internet 2025, 17(3), 124; https://doi.org/10.3390/fi17030124 - 11 Mar 2025
Viewed by 818
Abstract
In the digital age, sharing moments through photos has become a daily habit. However, every face captured in these photos is vulnerable to unauthorized identification and potential misuse through AI-powered synthetic content generation. Previously, we introduced SnapSafe, a secure system for enabling selective [...] Read more.
In the digital age, sharing moments through photos has become a daily habit. However, every face captured in these photos is vulnerable to unauthorized identification and potential misuse through AI-powered synthetic content generation. Previously, we introduced SnapSafe, a secure system for enabling selective image privacy focusing on facial regions for single-party scenarios. Recognizing that group photos with multiple subjects are a more common scenario, we extend SnapSafe to support multi-user facial privacy protection with dynamic access control designed for online photo platforms. Our approach introduces key splitting for access control, an owner-centric permission system for granting and revoking access to facial regions, and a request-based mechanism allowing subjects to initiate access permissions. These features ensure that facial regions remain protected while maintaining the visibility of non-facial content for general viewing. To ensure reproducibility and isolation, we implemented our solution using Docker containers. Our experimental assessment covered diverse scenarios, categorized as “Single”, “Small”, “Medium”, and “Large”, based on the number of faces in the photos. The results demonstrate the system’s effectiveness across all test scenarios, consistently performing face encryption operations in under 350 ms and achieving average face decryption times below 286 ms across various group sizes. The key-splitting operations maintained a 100% success rate across all group configurations, while revocation operations were executed efficiently with server processing times remaining under 16 ms. These results validate the system’s capability in managing facial privacy while maintaining practical usability in online photo sharing contexts. Full article
Show Figures

Figure 1

12 pages, 4420 KiB  
Article
Fabrication of MoS2@Fe3O4 Magnetic Catalysts with Photo-Fenton Reaction for Enhancing Tetracycline Degradation
by Zong-Lai Liu, Jia-Hong Sun, Bing Liu, Ya-Nan Chen and Wei Feng
Water 2025, 17(2), 235; https://doi.org/10.3390/w17020235 - 16 Jan 2025
Viewed by 897
Abstract
Tetracycline (TCs) is widely used in the treatment of human and animal infectious disease. TCs gives rise to a growing threat to the human health and environment protection due to its overuse. Therefore, it is important to remove TCs contaminants from waste effluents. [...] Read more.
Tetracycline (TCs) is widely used in the treatment of human and animal infectious disease. TCs gives rise to a growing threat to the human health and environment protection due to its overuse. Therefore, it is important to remove TCs contaminants from waste effluents. In this work, MoS2@Fe3O4 catalytic material was fabricated by the simple hydrothermal method, which was applied in the photo-Fenton system to degrade TCs. The crystal structure, surface morphology, elemental composition, chemical state, electrochemical properties, and separability of MoS2@Fe3O4 catalytic materials were analyzed by X-ray diffraction (XRD), scanning electron microscope (SEM), conventional and high-resolution transmission electron microscopy (TEM/HRTEM), X-ray photoelectron spectroscopy (XPS), electrochemical impedance spectroscopy (EIS), and vibrating sample magnetometry (VSM). Furthermore, MoS2@Fe3O4 could degrade 98.6% of TCs within 60 min under the optimum reaction conditions (the catalyst dosage of 3 g/L, H2O2 concentration of 5 mmol/L, the initial TCs concentration of 50 mg/L, and the initial pH of 5), which was a significant increase compared with pure Fe3O4. MoS2 can accelerate the Fe3+/Fe2+ cycle through electron transfer from Mo4+ to Fe3+, resulting in the improvement in the degradation efficiency of TCs. The quenching and electron paramagnetic resonance (EPR) results showed that OH and photogenic hole h+ was the main active species in the photo-Fenton system. What is more, MoS2@Fe3O4 catalytic materials had remarkable stability and reusability, and can be handily regained via magnetic separation technology in a real scenario. Full article
Show Figures

Figure 1

Back to TopTop