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
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
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
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
remove_circle_outline
remove_circle_outline
remove_circle_outline

Search Results (2,427)

Search Parameters:
Keywords = degree of reaction

Order results
Result details
Results per page
Select all
Export citation of selected articles as:
21 pages, 1442 KiB  
Article
Enzyme Modifications of Red Deer Fat to Adjust Physicochemical Properties for Advanced Applications
by Tereza Novotná, Jana Pavlačková, Robert Gál, Ladislav Šiška, Miroslav Fišera and Pavel Mokrejš
Molecules 2025, 30(15), 3293; https://doi.org/10.3390/molecules30153293 - 6 Aug 2025
Abstract
Red deer fat makes up approximately 7–10% of the animal’s weight and is not currently used. Regarding sustainability in the food industry, it is desirable to look for opportunities for its processing and use, not only in the food industry. The aim of [...] Read more.
Red deer fat makes up approximately 7–10% of the animal’s weight and is not currently used. Regarding sustainability in the food industry, it is desirable to look for opportunities for its processing and use, not only in the food industry. The aim of this study is the enzymatic modification of red deer fat, leading to modification of its physicochemical properties, and the study of changes in phase transitions of modified fat, its structure, color, and texture. Hydrolysis was performed using sn-1,3-specific lipase at different water concentrations (10–30%) and reaction times (2–6 h). The results showed that there was a significant decrease in melting and crystallization temperatures with an increasing degree of hydrolysis, which was confirmed by differential scanning calorimetry. FTIR spectra revealed a decrease in the intensity of the ester bonds, indicating cleavage of triacylglycerols. Texture analysis of the modified fats confirmed a decrease in hardness of up to 50% and an increase in spreadability. The color parameter values remained within an acceptable range. The results show that enzymatic modification is an effective tool for targeted modification of red deer fat properties, and this expands the possibilities of its application in cosmetic matrices and food applications as functional lipids. Full article
Show Figures

Graphical abstract

14 pages, 3150 KiB  
Article
Research on the Influence Mechanism of Thermal Load on the Au-Sn Sealing Weld State on Three-Dimensional DPC Substrates
by Heran Zhao, Lihua Cao, ShiZhao Wang, He Zhang and Mingxiang Chen
Materials 2025, 18(15), 3678; https://doi.org/10.3390/ma18153678 - 5 Aug 2025
Abstract
Direct copper-plated ceramic (DPC) substrates have emerged as a favored solution for power device packaging due to their unique technical advantages. AuSn, characterized by its high hermeticity and environmental adaptability, represents the optimal sealing technology for DPC substrates. Through the application of vacuum [...] Read more.
Direct copper-plated ceramic (DPC) substrates have emerged as a favored solution for power device packaging due to their unique technical advantages. AuSn, characterized by its high hermeticity and environmental adaptability, represents the optimal sealing technology for DPC substrates. Through the application of vacuum sintering techniques and adjustment of peak temperatures (325 °C, 340 °C, and 355 °C), the morphology and composition of interfacial compounds were systematically investigated, along with an analysis of their formation mechanisms. A gradient aging experiment was designed (125 °C/150 °C/175 °C × oxygen/argon dual atmosphere × 600 h) to elucidate the synergistic effects of environmental temperature and atmosphere on the growth of intermetallic compounds (IMCs). The results indicate that the primary reaction in the sealing weld seam involves Ni interacting with Au-Sn to form (Ni, Au)3Sn2 and Au5Sn. However, upon completion of the sealing process, this reaction remains incomplete, leading to a coexistence state of (Ni, Au)3Sn2, Au5Sn, and AuSn. Additionally, Ni diffuses into the weld seam center via dendritic fracture and locally forms secondary phases such as δ(Ni) and ζ’(Ni). These findings suggest that the weld seam interface exhibits a complex, irregular, and asymmetric microstructure comprising multiple coexisting compounds. It was determined that Tpeak = 325 °C to 340 °C represents the ideal welding temperature range, where the weld seam morphology, width, and Ni diffusion degree achieve optimal states, ensuring excellent device hermeticity. Aging studies further demonstrate that IMC growth remains within controllable limits. These findings address critical gaps in the understanding of the microstructural evolution and interface characteristics of asymmetric welded joints formed by multi-material systems. Full article
Show Figures

Graphical abstract

19 pages, 2806 KiB  
Article
Operating Solutions to Improve the Direct Reduction of Iron Ore by Hydrogen in a Shaft Furnace
by Antoine Marsigny, Olivier Mirgaux and Fabrice Patisson
Metals 2025, 15(8), 862; https://doi.org/10.3390/met15080862 (registering DOI) - 1 Aug 2025
Viewed by 275
Abstract
The production of iron and steel plays a significant role in the anthropogenic carbon footprint, accounting for 7% of global GHG emissions. In the context of CO2 mitigation, the steelmaking industry is looking to potentially replace traditional carbon-based ironmaking processes with hydrogen-based [...] Read more.
The production of iron and steel plays a significant role in the anthropogenic carbon footprint, accounting for 7% of global GHG emissions. In the context of CO2 mitigation, the steelmaking industry is looking to potentially replace traditional carbon-based ironmaking processes with hydrogen-based direct reduction of iron ore in shaft furnaces. Before industrialization, detailed modeling and parametric studies were needed to determine the proper operating parameters of this promising technology. The modeling approach selected here was to complement REDUCTOR, a detailed finite-volume model of the shaft furnace, which can simulate the gas and solid flows, heat transfers and reaction kinetics throughout the reactor, with an extension that describes the whole gas circuit of the direct reduction plant, including the top gas recycling set up and the fresh hydrogen production. Innovative strategies (such as the redirection of part of the bustle gas to a cooling inlet, the use of high nitrogen content in the gas, and the introduction of a hot solid burden) were investigated, and their effects on furnace operation (gas utilization degree and total energy consumption) were studied with a constant metallization target of 94%. It has also been demonstrated that complete metallization can be achieved at little expense. These strategies can improve the thermochemical state of the furnace and lead to different energy requirements. Full article
(This article belongs to the Special Issue Recent Developments and Research on Ironmaking and Steelmaking)
Show Figures

Graphical abstract

20 pages, 3271 KiB  
Article
Calculation Model for the Degree of Hydration and Strength Prediction in Basalt Fiber-Reinforced Lightweight Aggregate Concrete
by Yanqun Sun, Haoxuan Jia, Jianxin Wang, Yanfei Ding, Yanfeng Guan, Dongyi Lei and Ying Li
Buildings 2025, 15(15), 2699; https://doi.org/10.3390/buildings15152699 - 31 Jul 2025
Viewed by 232
Abstract
The combined application of fibers and lightweight aggregates (LWAs) represents an effective approach to achieving high-strength, lightweight concrete. To enhance the predictability of the mechanical properties of fiber-reinforced lightweight aggregate concrete (LWAC), this study conducts an in-depth investigation into its hydration characteristics. In [...] Read more.
The combined application of fibers and lightweight aggregates (LWAs) represents an effective approach to achieving high-strength, lightweight concrete. To enhance the predictability of the mechanical properties of fiber-reinforced lightweight aggregate concrete (LWAC), this study conducts an in-depth investigation into its hydration characteristics. In this study, high-strength LWAC was developed by incorporating low water absorption LWAs, various volume fractions of basalt fiber (BF) (0.1%, 0.2%, and 0.3%), and a ternary cementitious system consisting of 70% cement, 20% fly ash, and 10% silica fume. The hydration-related properties were evaluated through isothermal calorimetry test and high-temperature calcination test. The results indicate that incorporating 0.1–0.3% fibers into the cementitious system delays the early hydration process, with a reduced peak heat release rate and a delayed peak heat release time compared to the control group. However, fitting the cumulative heat release over a 72-h period using the Knudsen equation suggests that BF has a minor impact on the final degree of hydration, with the difference in maximum heat release not exceeding 3%. Additionally, the calculation model for the final degree of hydration in the ternary binding system was also revised based on the maximum heat release at different water-to-binder ratios. The results for chemically bound water content show that compared with the pre-wetted LWA group, under identical net water content conditions, the non-pre-wetted LWA group exhibits a significant reduction at three days, with a decrease of 28.8%; while under identical total water content conditions it shows maximum reduction at ninety days with a decrease of 5%. This indicates that pre-wetted LWAs help maintain an effective water-to-binder ratio and facilitate continuous advancement in long-term hydration reactions. Based on these results, influence coefficients related to LWAs for both final degree of hydration and hydration rate were integrated into calculation models for degrees of hydration. Ultimately, this study verified reliability of strength prediction models based on degrees of hydration. Full article
Show Figures

Figure 1

23 pages, 9108 KiB  
Article
COx-Free Hydrogen Production via CH4 Decomposition on Alkali-Incorporated (Mg, La, Ca, Li) Ni-Al Catalysts
by Morgana Rosset, Yan Resing Dias, Liliana Amaral Féris and Oscar William Perez-Lopez
Nanoenergy Adv. 2025, 5(3), 10; https://doi.org/10.3390/nanoenergyadv5030010 - 30 Jul 2025
Viewed by 225
Abstract
The catalytic decomposition of CH4 is a promising method for producing high-purity COx-free hydrogen. A Ni-Al-LDH catalyst synthesized via coprecipitation was modified with alkali metals (Mg, La, Ca, or Li) through reconstruction to enhance catalytic activity and resistance to deactivation [...] Read more.
The catalytic decomposition of CH4 is a promising method for producing high-purity COx-free hydrogen. A Ni-Al-LDH catalyst synthesized via coprecipitation was modified with alkali metals (Mg, La, Ca, or Li) through reconstruction to enhance catalytic activity and resistance to deactivation during catalytic methane decomposition (CMD). The catalysts were evaluated by two activation methods: H2 reduction and direct heating with CH4. The MgNA-R catalyst achieved the highest CH4 conversion (65%) at 600 °C when reduced with H2, attributed to a stronger Ni-Al interaction. Under CH4 activation, LaNA-C achieved a 55% conversion at the same temperature, associated with a smaller crystallite size and higher reducibility due to La incorporation. Although all catalysts deactivated due to carbon deposition and/or sintering, LaNA-C was the only sample that could resist deactivation for a longer period, as La appears to have a protective effect on the active phase. Post-reaction characterizations revealed the formation of graphitic and filamentous carbon. Raman spectroscopy exhibited a higher degree of graphitization and structural order in LaNA-C, whereas SEM showed a more uniform distribution of carbon filaments. TEM confirmed the presence of multi-walled carbon nanotubes with encapsulated Ni particles in La-promoted samples. These results demonstrate that La addition improves the catalytic performance under CH4 activation and carbon structure. This finding offers a practical advantage for CMD processes, as it reduces or eliminates the need to use hydrogen during catalyst activation. Full article
(This article belongs to the Special Issue Novel Energy Materials)
Show Figures

Graphical abstract

13 pages, 436 KiB  
Article
Hospital Pharmacists’ Perspectives on Adverse Drug Reaction Reporting in Developed and Developing  Countries: A Comparative Pilot Study
by Javeria Khalid, Tarilate Temedie-Asogwa, Marjan Zakeri and Sujit S. Sansgiry
Pharmacy 2025, 13(4), 103; https://doi.org/10.3390/pharmacy13040103 - 29 Jul 2025
Viewed by 247
Abstract
Adverse drug reactions (ADRs) significantly affect patient safety and healthcare spending worldwide. Hospital pharmacists are uniquely positioned to address ADRs due to their crucial role in medication management. However, underreporting remains a global concern, especially in developing countries, where pharmacovigilance systems are inadequately [...] Read more.
Adverse drug reactions (ADRs) significantly affect patient safety and healthcare spending worldwide. Hospital pharmacists are uniquely positioned to address ADRs due to their crucial role in medication management. However, underreporting remains a global concern, especially in developing countries, where pharmacovigilance systems are inadequately developed. Therefore, this pilot study aimed to evaluate and compare the knowledge, attitudes, perceived barriers, and facilitators regarding ADR reporting by hospital pharmacists in a developed (US) and a developing (Pakistan) country. A cross-sectional survey was conducted, using a pre-validated questionnaire. The pharmacists, possessing a minimum of one year’s hospital experience, were selected via convenience sampling. Out of 151 respondents, included in the final analysis (US: n = 51; Pakistan: n = 100), the majority were female (62.3%), aged 29–35 years (38%), and possessed a Pharm. D degree (49.7%). The knowledge (US: 6.03 ± 0.27 vs. Pakistan:5.69 ± 0.25, p-value = 0.193) and attitude scores (US: 32.02 ± 0.73 vs. Pakistan: 32.63 ± 0.67; p-value = 0.379) exhibited no significant differences between the groups. Nonetheless, barriers at both the individual and systemic levels were more pronounced in the developing country. Important facilitators reported were mobile applications for ADR reporting, specialized training, and intuitive reporting tools. In conclusion, we found that pharmacists in both settings exhibit comparable knowledge and positive attitudes towards ADR reporting, though specific contextual barriers are present. Interventions customized to the local hospital infrastructure are crucial for enhancing ADR reporting, particularly in resource-constrained settings. Full article
(This article belongs to the Section Pharmacy Practice and Practice-Based Research)
Show Figures

Figure 1

19 pages, 3200 KiB  
Article
Polyphosphoramidate Glycohydrogels with Biorecognition Properties and Potential Antibacterial Activity
by Zornica Todorova, Oyundari Tumurbaatar, Violeta Mitova, Neli Koseva, Iva Ugrinova, Penka Petrova and Kolio Troev
Molecules 2025, 30(15), 3140; https://doi.org/10.3390/molecules30153140 - 26 Jul 2025
Viewed by 250
Abstract
In the present study, for the first time, a biodegradable and non-toxic polyphosphoramidate glycohydrogel (PPAGHGel) was prepared by crosslinking a polyphosphoramidate glycoconjugate (PPAG) with hexamethylene diisocyanate (HMDI) under mild conditions. Poly(oxyethylene H-phosphonate) (POEHP) was used as a precursor and was converted into PPAG [...] Read more.
In the present study, for the first time, a biodegradable and non-toxic polyphosphoramidate glycohydrogel (PPAGHGel) was prepared by crosslinking a polyphosphoramidate glycoconjugate (PPAG) with hexamethylene diisocyanate (HMDI) under mild conditions. Poly(oxyethylene H-phosphonate) (POEHP) was used as a precursor and was converted into PPAG via the Staudinger reaction with glucose-containing azide (2-p-azidobenzamide-2-deoxy-1,3,4,6-tetra-O-trimethylsilyl-α-D-glucopyranose). Then, crosslinking of PPAG was performed to yield PPAGHGel, which was thoroughly characterized. The gel showed a gel fraction of 83%, a swelling degree of 1426 ± 98%, and G″ = 1560 ± 65 Pa. The gel was fully degraded by alkaline phosphatase (400 U/L, pH 9) in 19 days, while hydrolytically, up to 52% degradation was observed under similar conditions. Multivalent studies of the obtained hydrogel with lectin–Concanavalin A were performed. PPAGHGel binds 92% of Concanavalin A within 24 h and the complex remains stable until the amount of glucose reaches 0.3 mM. PPAGHGel acts as a stabilizer for silver nanoparticles (12 nm). SEM shows pores measuring 10 µm (surface) and 0.1 mm (interior) with capillary channels, confirming the gel’s suitability for biosensors, drug delivery, or wound dressings. The cytotoxic (IC50) and cell-adhesive properties of the obtained hydrogel were investigated on human cell lines (HeLa). Antibacterial activity tests were also performed with gel containing silver nanoparticles against skin-associated pathogenic bacteria. The results show that PPAGHGel possesses excellent biocompatibility, non-adhesive properties and antibacterial activity. Full article
Show Figures

Figure 1

20 pages, 4162 KiB  
Article
Discovering the Emotions of Frustration and Confidence During the Application of Cognitive Tests in Mexican University Students
by Marco A. Moreno-Armendáriz, Jesús Mercado-Ríos, José E. Valdez-Rodríguez, Rolando Quintero and Victor H. Ponce-Ponce
Big Data Cogn. Comput. 2025, 9(8), 195; https://doi.org/10.3390/bdcc9080195 - 24 Jul 2025
Viewed by 367
Abstract
Emotion detection using computer vision has advanced significantly in recent years, achieving remarkable performance that, in some cases, surpasses that of humans. Convolutional neural networks (CNNs) excel in this task by capturing facial features that allow for effective emotion classification. However, most research [...] Read more.
Emotion detection using computer vision has advanced significantly in recent years, achieving remarkable performance that, in some cases, surpasses that of humans. Convolutional neural networks (CNNs) excel in this task by capturing facial features that allow for effective emotion classification. However, most research focuses on basic emotions, such as happiness, anger, or sadness, neglecting more complex emotions, like frustration. People set expectations or goals to meet; if they do not happen, frustration arises, generating reactions such as annoyance, anger, and disappointment, which can harm confidence and motivation. These aspects make it especially relevant in mental health and educational contexts, where detecting it could help mitigate its adverse effects. In this research, we developed a CNN-based approach to detect frustration through facial expressions. The scarcity of specific datasets for this task led us to create an experimental protocol to generate our dataset. This classification task presents a high degree of difficulty due to the variability in facial expressions among different participants when feeling frustrated. Despite this, our new model achieved an F1-score of 0.8080, thus obtaining an adequate baseline model. Full article
(This article belongs to the Special Issue Application of Deep Neural Networks)
Show Figures

Figure 1

16 pages, 2458 KiB  
Article
Kinetics of H2O2 Decomposition and Bacteria Inactivation in a Continuous-Flow Reactor with a Fixed Bed of Cobalt Ferrite Catalyst
by Nazarii Danyliuk, Viktor Husak, Volodymyra Boichuk, Dorota Ziółkowska, Ivanna Danyliuk and Alexander Shyichuk
Appl. Sci. 2025, 15(15), 8195; https://doi.org/10.3390/app15158195 - 23 Jul 2025
Viewed by 224
Abstract
As a result of the catalytic decomposition of H2O2, hydroxyl radicals are produced. Hydroxyl radicals are strong oxidants and effectively inactivate bacteria, ensuring water disinfection without toxic chlorinated organic by-products. The kinetics of bacterial inactivation were studied in a [...] Read more.
As a result of the catalytic decomposition of H2O2, hydroxyl radicals are produced. Hydroxyl radicals are strong oxidants and effectively inactivate bacteria, ensuring water disinfection without toxic chlorinated organic by-products. The kinetics of bacterial inactivation were studied in a laboratory-scale flow catalytic reactor. A granular cobalt ferrite catalyst was thoroughly characterized using XRD and XRF techniques, SEM with EDS, and Raman spectroscopy. At lower H2O2 concentrations, H2O2 decomposition follows first-order reaction kinetics. At higher H2O2 concentrations, the obtained kinetics lines suggest that the reaction order increases. The kinetics of bacterial inactivation in the developed flow reactor depends largely on the initial number of bacteria. The initial bacterial concentrations in laboratory tests were within the range typical of real river water. A regression model was developed that relates the degree of bacterial inactivation to the initial number of bacteria, the initial H2O2 concentration, and the contact time of water with the catalyst. Full article
(This article belongs to the Special Issue Water Pollution and Wastewater Treatment Chemistry)
Show Figures

Figure 1

20 pages, 5939 KiB  
Article
Mechanistic Insights into the Hot-Spot Formation and Pyrolysis of LLM-105 with Different Void Defects: A ReaxFF Molecular Dynamics Study
by Mengyun Mei, Zijian Sun, Lixin Ye and Weihua Zhu
Molecules 2025, 30(14), 3016; https://doi.org/10.3390/molecules30143016 - 18 Jul 2025
Viewed by 321
Abstract
To investigate the influences of void defects of different sizes, molecular dynamics combined with ReaxFF-lg reactive force field was used to study the hot-spot formation mechanism and thermal decomposition behavior of 2,6-diamino-3,5-dinitropyrazine-1-oxide (LLM-105) crystals with different void defects at 2500 K. The results [...] Read more.
To investigate the influences of void defects of different sizes, molecular dynamics combined with ReaxFF-lg reactive force field was used to study the hot-spot formation mechanism and thermal decomposition behavior of 2,6-diamino-3,5-dinitropyrazine-1-oxide (LLM-105) crystals with different void defects at 2500 K. The results indicate that larger void defects are more conducive to the formation of hot-spots. The consistency of the trends in time evolution of the potential energy, species numbers, and small molecules amounts between the ideal and void-containing LLM-105 crystals demonstrates that the presence of the void defect does not alter the decomposition mechanism of the LLM-105 molecule. An increase in the size of the void defect significantly increases the degree of diffusion of the C, H, O, and N atoms in the crystals, which affects the effective collisions between the atoms and thus alters the occurrence frequency of relevant reactions and the production of relevant products. Full article
(This article belongs to the Section Physical Chemistry)
Show Figures

Figure 1

16 pages, 4723 KiB  
Article
The Effect of the Fiber Diameter, Epoxy-to-Amine Ratio, and Degree of PVA Saponification on CO2 Adsorption Properties of Amine-Epoxy/PVA Nanofibers
by Chisato Okada, Zongzi Hou, Hiroaki Imoto, Kensuke Naka, Takeshi Kikutani and Midori Takasaki
Polymers 2025, 17(14), 1973; https://doi.org/10.3390/polym17141973 - 18 Jul 2025
Viewed by 302
Abstract
Achieving carbon neutrality requires not only reducing CO2 emissions but also capturing atmospheric CO2. Direct air capture (DAC) using amine-based adsorbents has emerged as a promising approach. In this study, we developed amine-epoxy/poly(vinyl alcohol) (AE/PVA) nanofibers via electrospinning and in [...] Read more.
Achieving carbon neutrality requires not only reducing CO2 emissions but also capturing atmospheric CO2. Direct air capture (DAC) using amine-based adsorbents has emerged as a promising approach. In this study, we developed amine-epoxy/poly(vinyl alcohol) (AE/PVA) nanofibers via electrospinning and in situ thermal polymerization. PVA was incorporated to enhance spinnability, and B-staging of AE enabled fiber formation without inline heating. We systematically investigated the effects of electrospinning parameters, epoxy-to-amine ratios (E/A), and the degree of PVA saponification on CO2 adsorption performance. Thinner fibers, obtained by adjusting spinning conditions, exhibited faster adsorption kinetics due to increased surface area. Varying the E/A revealed a trade-off between adsorption capacity and low-temperature desorption efficiency, with secondary amines offering a balanced performance. Additionally, highly saponified PVA improved thermal durability by minimizing side reactions with amines. These findings highlight the importance of optimizing fiber morphology, chemical composition, and polymer properties to enhance the performance and stability of AE/PVA nanofibers for DAC applications. Full article
(This article belongs to the Section Circular and Green Sustainable Polymer Science)
Show Figures

Figure 1

19 pages, 4069 KiB  
Article
Influence of Silane-Modified Coal Gangue Ceramsite on Properties of Ultra-High-Performance Concrete
by Yuanjie Qin, Sudong Hua, Dongrui Zhang and Hongfei Yue
Appl. Sci. 2025, 15(14), 7968; https://doi.org/10.3390/app15147968 - 17 Jul 2025
Viewed by 272
Abstract
In this study, a kind of sustainable ultra-high-performance concrete (UHPC) was designed by using coal gangue ceramsite (CGC) and a modified Andreasen–Andersen model. However, when CGC lightweight aggregate with high water absorption is used in UHPC with a low water–cement ratio, CGC has [...] Read more.
In this study, a kind of sustainable ultra-high-performance concrete (UHPC) was designed by using coal gangue ceramsite (CGC) and a modified Andreasen–Andersen model. However, when CGC lightweight aggregate with high water absorption is used in UHPC with a low water–cement ratio, CGC has an adverse effect on the working performance of UHPC and may lead to the decrease of mechanical properties. This study found that a 5% silane coupling agent KH560 can make CGC hydrophobic, and cause its contact angle to increase from 0° to 111.32°. Adding 100% hydrophobic modified CGC into UHPC will significantly improve its working performance, with the highest increase of 38.51%. At the same time, the addition of 20% modified CGC can further improve the compressive strength of UHPC (28 days reached 150.1 MPa), reduce the internal porosity by 21.4%, and make the interface bond more compact. In addition, the hydration degree of UHPC has also been improved, a result caused by the cement obtaining more free water for a more complete hydration reaction. This study can provide a new scheme for solving the problem of the solid waste of coal gangue. Full article
Show Figures

Figure 1

28 pages, 3409 KiB  
Article
Wobble Board Instability Enhances Compensatory CoP Responses to CoM Movement Across Timescales
by Mahsa Barfi, Theodoros Deligiannis, Brian Schlattmann, Karl M. Newell and Madhur Mangalam
Sensors 2025, 25(14), 4454; https://doi.org/10.3390/s25144454 - 17 Jul 2025
Viewed by 248
Abstract
This study investigated the interplay of bodily degrees of freedom (DoFs) governing the collective variable comprising the center of pressure (CoP) and center of mass (CoM) in postural control through the analytical lens of multiplicative interactions across scales. We employed a task combination [...] Read more.
This study investigated the interplay of bodily degrees of freedom (DoFs) governing the collective variable comprising the center of pressure (CoP) and center of mass (CoM) in postural control through the analytical lens of multiplicative interactions across scales. We employed a task combination involving a wobble board, introducing mechanical instability mainly along the mediolateral (ML) axis and the Trail Making Task (TMT), which imposes precise visual demands primarily along the anteroposterior (AP) axis. Using Multiscale Regression Analysis (MRA), a novel analytical method rooted in Detrended Fluctuation Analysis (DFA), we scrutinized CoP-to-CoM and CoM-to-CoP effects across multiple timescales ranging from 100ms to 10s. CoP was computed from ground reaction forces recorded via a force plate, and CoM was derived from full-body 3D motion capture using a biomechanical model. We found that the wobble board attenuated CoM-to-CoP effects across timescales ranging from 100to400ms. Further analysis revealed nuanced changes: while there was an overall reduction, this encompassed an accentuation of CoM-to-CoP effects along the AP axis and a decrease along the ML axis. Importantly, these alterations in CoP’s responses to CoM movements outweighed any nonsignificant effects attributable to the TMT. CoM exhibited no sensitivity to CoP movements, regardless of the visual and mechanical task demands. In addition to identifying the characteristic timescales associated with bodily DoFs in facilitating upright posture, our findings underscore the critical significance of directionally challenging biomechanical constraints, particularly evident in the amplification of CoP-to-CoM effects along the AP axis in response to ML instability. These results underscore the potential of wobble board training to enhance the coordinative and compensatory responses of bodily DoFs to the shifting CoM by prompting appropriate adjustments in CoP, thereby suggesting their application for reinstating healthy CoM–CoP dynamics in clinical populations with postural deficits. Full article
Show Figures

Figure 1

16 pages, 8045 KiB  
Article
Modification of G-C3N4 by the Surface Alkalinization Method and Its Photocatalytic Depolymerization of Lignin
by Zhongmin Ma, Ling Zhang, Lihua Zang and Fei Yu
Materials 2025, 18(14), 3350; https://doi.org/10.3390/ma18143350 - 17 Jul 2025
Viewed by 315
Abstract
The efficient depolymerization of lignin has become a key challenge in the preparation of high-value-added chemicals. Graphitic carbon nitride (g-C3N4)-based photocatalytic system shows potential due to its mild and green characteristics over other depolymerization methods. However, its inherent defects, [...] Read more.
The efficient depolymerization of lignin has become a key challenge in the preparation of high-value-added chemicals. Graphitic carbon nitride (g-C3N4)-based photocatalytic system shows potential due to its mild and green characteristics over other depolymerization methods. However, its inherent defects, such as a wide band gap and rapid carrier recombination, severely limit its catalytic performance. In this paper, a g-C3N4 modification strategy of K⁺ doping and surface alkalinization is proposed, which is firstly applied to the photocatalytic depolymerization of the lignin β-O-4 model compound (2-phenoxy-1-phenylethanol). K⁺ doping is achieved by introducing KCl in the precursor thermal polymerization stage to weaken the edge structure strength of g-C3N4, and post-treatment with KOH solution is combined to optimize the surface basic groups. The structural/compositional evolution of the materials was analyzed by XRD, FTIR, and XPS. The morphology/element distribution was visualized by SEM-EDS, and the optoelectronic properties were evaluated by UV–vis DRS, PL, EIS, and transient photocurrent (TPC). K⁺ doping and surface alkalinization synergistically regulate the layered structure of the material, significantly increase the specific surface area, introduce nitrogen vacancies and hydroxyl functional groups, effectively narrow the band gap (optimized to 2.35 eV), and inhibit the recombination of photogenerated carriers by forming electron capture centers. Photocatalytic experiments show that the alkalinized g-C3N4 can completely depolymerize 2-phenoxy-1-phenylethanol with tunable product selectivity. By adjusting reaction time and catalyst dosage, the dominant product can be shifted from benzaldehyde (up to 77.28% selectivity) to benzoic acid, demonstrating precise control over oxidation degree. Mechanistic analysis shows that the surface alkaline sites synergistically optimize the Cβ-O bond breakage path by enhancing substrate adsorption and promoting the generation of active oxygen species (·OH, ·O2). This study provides a new idea for the efficient photocatalytic depolymerization of lignin and lays an experimental foundation for the interface engineering and band regulation strategies of g-C3N4-based catalysts. Full article
(This article belongs to the Section Catalytic Materials)
Show Figures

Figure 1

14 pages, 1354 KiB  
Article
Assessment of the Interactions Between Hemicellulose Xylan and Kaolinite Clay: Structural Characterization and Adsorptive Behavior
by Enzo Díaz, Leopoldo Gutiérrez, Elizabeth Elgueta, Dariela Núñez, Isabel Carrillo-Varela and Vicente A. Hernández
Polymers 2025, 17(14), 1958; https://doi.org/10.3390/polym17141958 - 17 Jul 2025
Viewed by 314
Abstract
In this study, a methacrylic derivative of xylan (XYLMA) was synthesized through transesterification reactions, with the aim of evaluating its physicochemical behavior and its interaction with kaolinite particles. Structural characterization by FT-IR and NMR spectroscopy confirmed the incorporation of methacrylic groups into the [...] Read more.
In this study, a methacrylic derivative of xylan (XYLMA) was synthesized through transesterification reactions, with the aim of evaluating its physicochemical behavior and its interaction with kaolinite particles. Structural characterization by FT-IR and NMR spectroscopy confirmed the incorporation of methacrylic groups into the xylan (XYL) structure, with a degree of substitution of 0.67. Thermal analyses (TGA and DSC) showed a decrease in melting temperature and enthalpy in XYLMA compared to XYL, attributed to a loss of structural rigidity. Thermal analyses (TGA and DSC) revealed a decrease in the melting temperature and enthalpy of XYLMA compared to XYL, which is attributed to a loss of structural rigidity and a reduction in the crystalline order of the biopolymer. Aggregation tests in solution revealed that XYLMA exhibits amphiphilic behavior, forming micellar structures at a critical aggregation concentration (CAC) of 62 mg L−1. In adsorption studies on kaolinite, XYL showed greater affinity than XYLMA, especially at acidic pH, due to reduced electrostatic forces and a greater number of hydroxyl groups capable of forming hydrogen bonds with the mineral surface. In contrast, modification with methacrylic groups in XYLMA reduced its adsorption capacity, probably due to the formation of supramolecular aggregates. These results suggest that interactions between xylan and kaolinite clay are key to understanding the role that hemicelluloses play in increasing copper recovery when added to flotation cells during the processing of copper sulfide ores with high clay content. Full article
Show Figures

Figure 1

Back to TopTop