Search Results (10,725)

Graphene incorporation into polymer fibers offers a strategy to tune nanoscale morphology while preserving mechanical conformity for flexible composite applications. Graphene-based dopants can enable modulation of polymer fiber structure; however, the relationship between graphene incorporation, fiber morphology, and mechanical flexibility must be evaluated. This study investigates the integration of graphene oxide (GO) and reduced graphene oxide (RGO) into fibrous materials to tailor the structural and surface characteristics by fabricating GO- and RGO-enhanced poly(vinylidene fluoride) (PVDF) fibers via a wet-spinning process and examining the tunability of their morphology and its influence on mechanical properties. The effect of graphene doping and reduction state on fiber architecture is explored using scanning electron microscopy (SEM), atomic force microscopy (AFM), and Brunauer–Emmett–Teller (BET) surface area analysis. Fourier transform infrared (FTIR) and Raman spectroscopy analyses confirmed the incorporation and reduction of graphene derivatives within the PVDF matrix while revealing corresponding changes in chemical functionality and the piezoelectric phase of PVDF. Mechanical flexibility is assessed through tensile testing, revealing increased stiffness with graphene addition, although maintaining sufficient structural integrity for wearable applications. These results collectively demonstrate that graphene doping provides a facile route to engineer composite fibers, enabling a balance between morphological complexity and mechanical compliancy, while establishing graphene-enhanced fibers as promising materials for flexible sensing systems and wearable smart textiles. Full article

Outdoor ecological practice is essential for cultivating ecological literacy; however, there is currently a relative lack of comprehensive outdoor practical teaching case designs for class-based teaching. This study describes the design of an experimental teaching case for ecological education involving UAV-based field data collection. For the scheme, we selected the Xinhui Tangerine Peel Germplasm Resources Conservation Center in Jiangmen City, Guangdong Province as the study area, utilizing the DJI Phantom 4 RTK drone, which serves as the equipment for experimental teaching. The experiment is structured into three phases: indoor preparation, field execution, and data processing. Students from four groups collaboratively conducted aerial surveys across 24 partitioned plots, with flight altitudes stratified between groups to ensure safety and data integrity. (1) In the indoor preparation phase, appropriate single-flight operational units were defined. QGIS software (version 3.26.2) was employed for zonal mission planning, and suitable flight altitudes were estimated using contour data. (2) Field experiment phase. This involved conducting a comprehensive survey of the on-site environment, selecting suitable takeoff and landing points, dividing students into teams to carry out UAV-image-acquisition tasks, and assigning different altitudes for flight routes among the teams. (3) After the fieldwork, students processed imagery using Agisoft Metashape (version 2.0.1) to generate orthomosaics and digital surface models, and engaged in ecological interpretation of the results. The experimental design ensured orderly execution, complete data coverage, and active student participation. The results indicate the approach effectively enhanced students’ UAV operational skills, outdoor problem-solving abilities, and teamwork capabilities, while deepening their ecological understanding through real-world inquiry. This case provides a replicable model for integrating UAV technology into ecological education, contributing to the transformation of ecological awareness into actionable practice. Full article

This study investigates the role of silicon (Si) addition in governing the evolution of phase symmetry and microstructural stability in a high-entropy alloy (HEA) synthesized via powder metallurgy. Mechanically alloyed powders were consolidated through conventional sintering, followed by systematic heat treatment to examine symmetry-driven phase transformations. Particular attention is given to the symmetry relationship between body-centered cubic (BCC) and face-centered cubic (FCC) crystal structures and their compositional stabilization mechanisms. X-ray diffraction and microstructural analyses reveal that Si incorporation modifies lattice symmetry, promotes controlled phase transformation, and influences the balance between competing crystallographic phases. The addition of Si contributes to symmetry stabilization by reducing heterogeneity in lattice distortion and suppressing grain coarsening during thermal exposure. These findings demonstrate that compositional tuning can regulate structural symmetry and phase equilibrium in multicomponent alloy systems. The work provides insight into symmetry-controlled material design strategies for enhancing the thermal robustness and structural reliability of HEAs for high-temperature applications. Full article

High-quality direct reduced iron (DRI) powder is essential for applications in catalysis, adsorption, and electromagnetic materials. However, its tendency to reoxidize during processing presents a significant challenge. This study investigates the oxidation behavior of DRI powder during wet ball-milling treatment. Samples were characterized using chemical phase dissolution, X-ray diffraction (XRD), scanning electron microscopy with energy-dispersive X-ray spectroscopy (SEM-EDS), and X-ray photoelectron spectroscopy (XPS) to assess both bulk and surface oxidation. The results reveal that significant oxidation occurs during the wet grinding and subsequent processing stages, with the relative oxidation degree (ROD) of the iron powder increasing sharply from 6.08% to 26.81% as the grinding time is extended from 20 to 40 min. SEM-EDS analysis indicates that oxidation is particularly pronounced in particles smaller than 10 μm. XRD confirms the gradual transformation of Fe⁰ to Fe₃O₄ with prolonged grinding, corroborating the chemical analysis. Furthermore, XPS analysis of the Fe 2p, Fe 3p, Fe 3s, and O 1s core levels reveals that the nanoscale surface is composed of Fe₂O₃, Fe₃O₄, Fe(OH)₃, and FeOOH—a composition distinctly different from the bulk Fe/Fe₃O₄ phases. These findings underscore the critical roles of particle size and mechanical activation in driving DRI reoxidation during wet milling. Full article

Efficiently converting natural capital into economic assets is a critical challenge in urban–rural transformation, yet the interactive mechanism between institutional land reform and physical spatial restructuring remains underexplored. While traditional frameworks emphasize institutional design, this study identifies a “Spatial-First” mechanism where physical reconfiguration serves as a spatial mediator to catalyze property rights breakthroughs. Using an entropy-weighted coupling coordination model, we analyzed policy dynamics in Nanhai District, China, a unique “dual-pilot” zone, from 2020 to 2024. The results indicate a nonlinear leap in the Coupling Coordination Degree (D) from 0.100 to 0.978. We interpret this surge as a policy-driven shock during the intensive pilot phase, where substantive spatial integration (0.719) effectively bypassed high transaction costs inherent in collective tenure, outpacing institutional progress (0.281). However, an Ecological Lag was observed; the disproportionately low weighting of the ecological carrier index (7.09%) suggests that current gains are primarily driven by green industrialization rather than the expansion of absolute ecological stock. This study concludes that while spatial tools can effectively unlock natural capital value in the short term, long-term sustainability necessitates a strategic shift from administrative-led economic efficiency to market-based ecological restoration. Full article

Channel pruning enables model acceleration by removing channels from convolutional neural networks (CNNs). However, many existing methods adopt a “hard removal” strategy that directly removing low-importance channels, leading to severe feature loss and accuracy degradation. To address this issue, we propose Reconstruction and Consolidation Pruning (RCP), a pruning framework that decouples the pruning process into a pruning-training phase and an inference phase. During pruning training, RCP generates a pruning strategy based on channel importance under a global pruning rate constraint, and constructs a feature reloading mechanism. This mechanism utilizes a learnable $1\times 1$ compensation convolution to adaptively transfer and fuse discriminative features hidden in the pruned channels into the retained channels. In the inference phase, RCP adopts a linear reparameterization strategy to seamlessly consolidate the compensation branches into the main network branch without loss of performance, ensuring zero additional operator overhead during inference. This reversible structural transformation ensures that the training-time augmented architecture and the inference-time compact architecture are functionally identical under linear consolidation. Experimental results show that at 50% FLOPs reduction, RCP incurs only a 0.84% accuracy drop on ResNet-50 (ImageNet-1K), while at 53% FLOPs reduction it achieves a 0.07% accuracy improvement for ResNet-56 (CIFAR-10), validating the proposed method’s effectiveness and superiority under high compression rates. Full article

Zirconia-based hybrid blends at various molecular or nanometer scales have attracted significant interest from a technological perspective. In particular, several inorganic-organic hybrids are being applied in the biomedical field. In this context, inorganic ZrO₂ and hybrids composed of ZrO₂, and polyethylene glycol (PEG) have been synthesized through the sol–gel process and characterized from both morphological and spectroscopic viewpoints to explore their potential as hybrid biomaterials. Atomic Force Microscopy (AFM) has enabled a quantitative assessment of the surface roughness of bioactive sol–gel-based materials. The findings indicated an increase in material porosity in relation to the amount of PEG present in the systems, underscoring the important role of PEG in influencing the morphological characteristics of zirconia-based blends. AFM images display the typical globular structure of PEG spread across the surface of all systems. All hybrid systems seem to be uniform, and no phase separation is evident, thereby validating that the produced materials are hybrid nanostructured ones. The simultaneous presence of both inorganic and organic phases was verified using Fourier-transform infrared spectroscopy (FT-IR). FT-IR deconvolution in 850–550 cm⁻¹ region showed that PEG progressively perturbs the Zr–O–Zr network, increasing disorder and establishing more flexible inorganic domains at high PEG content. Increasing polymer amount enhanced cell viability against NIH-3T3 cell line, while antibacterial activity decreased, with pure ZrO₂ showing the strongest inhibition against Escherichia coli (E. coli). Full article

Historically, the electricity sector in Greece was based on local lignite, which provided a stable and affordable base for electricity production. However, current European policy directions, including decarbonization and climate neutrality by 2050, have accelerated the transformation of traditional energy models, resulting in a gradual phasing-out of fossil fuels and an increasing integration of Renewable Energy Sources (RES). In line with EU policy priorities and in light of the new dynamics shaped by the EU Emissions Trading System (EU ETS), lignite gradually became unprofitable for the national economy, leading the Greek government to announce an accelerated lignite phase-out plan. However, the phase-out of domestic lignite, although consistent with climate objectives, rapidly increased the country’s energy dependency on natural gas and its exposure to natural gas price volatility. At the same time, increased investment in solar and wind technologies has reshaped the electricity mix; yet market design, limited system flexibility and inadequate infrastructure and storage capacity have not allowed the full utilization of RES benefits. This structural gap, in turn, raises critical questions about resilience and affordability. The paper provides evidence on these issues and offers a critical evaluation of the decarbonization pathway that has reshaped the country’s energy dependency. Full article

This study aims to explore and propose a design-oriented methodology for solar–thermal methanol reforming (ST-MSR) hydrogen production equipment suitable for marine applications. To address key challenges such as the intermittency of solar energy, spatial and environmental constraints on board ships, operational safety, and user experience, a multidisciplinary integrated-design decision-making framework is established. First, the Kano model is employed to systematically analyze the latent needs of target users regarding ST-MSR equipment, while the analytic hierarchy process (AHP) is used to determine the weighting of evaluation criteria. Second, the theory of inventive problem solving (TRIZ) is applied to generate innovative conceptual design solutions. Finally, the technique for order preference by similarity to an ideal solution (TOPSIS) is adopted to conduct a multi-dimensional comprehensive evaluation and optimization-based selection of the conceptual alternatives. The optimal design scheme is thus identified in terms of energy performance, product characteristics, user experience, economic feasibility, and environmental adaptability. The results indicate that the microchannel and phase-change thermal-storage integrated solar–thermal-tracking chemical reactor achieves the highest comprehensive evaluation score among the proposed schemes, demonstrating superior performance in terms of safety, energy efficiency, and adaptability to marine environments. This research provides a systematic industrial design methodology and practical reference for the design and product development of clean energy equipment for ships, contributing to the green and sustainable transformation of the maritime industry. Full article

Background: Direct oral anticoagulants (DOACs) have transformed antithrombotic therapy but carry significant bleeding risks requiring prompt reversal. Recent regulatory changes have altered the reversal landscape, notably with the withdrawal of andexanet alfa from the U.S. market. Anticoagulation stewardship programs (ASPs) are essential for navigating this evolving environment and optimizing safe use of anticoagulants. Methods: This narrative review synthesizes evidence from landmark clinical trials (RE-VERSE AD, ANNEXA-4, ANNEXA-I), contemporary guidelines, emerging literature on reversal agents, and critical regulatory updates including the 2025 U.S Food and Drug Administration (FDA) withdrawal of andexanet alfa. Results: Idarucizumab remains the only FDA-approved specific antidote for dabigatran. Following the withdrawal of andexanet alfa, prothrombin complex concentrates (PCCs), both 4-factor and activated are now the primary reversal options for Factor Xa inhibitors, with recent evidence demonstrating comparable hemostatic efficacy. Ciraparantag, a universal reversal agent, is currently in Phase III development. Effective ASPs must now adapt protocols to the post-andexanet era while ensuring timely access to alternative reversal strategies. Conclusions: The reversal landscape has undergone a fundamental transformation with the loss of andexanet alfa. Success in DOAC-associated bleeding management now depends on optimizing PCC-based strategies, integrating systematic stewardship approaches, and preparing for emerging universal antidotes. Institutions must urgently update algorithms, ensure PCC availability, and monitor outcomes in this new therapeutic environment. Full article

Cellulose paper, a natural polymeric dielectric, determines the lifetime of oil–paper insulation systems in transformers, yet its molecular degradation behavior in ester-based insulating media remains insufficiently clarified. This study investigates the electro–thermal aging of cellulose polymer immersed in soybean-based natural ester (SBNE) and palm fatty acid ester (PFAE), with emphasis on depolymerization and its relationship with partial discharge (PD) activity. Accelerated aging experiments were conducted under combined electrical and thermal stress, and the evolution of the degree of polymerization (DP) was measured to quantify polymer chain scission. Phase-resolved PD (PRPD) patterns were recorded during aging, and multi-dimensional statistical features were extracted and reduced using principal component analysis to characterize degradation-sensitive electrical responses. The results show a progressive decrease in DP with aging time in both ester media, accompanied by distinct PD evolution characteristics, indicating different influences of the two esters on cellulose polymer stability. An ensemble learning model integrating multiple classifiers was further employed to identify aging stages based on PD features, achieving reliable discrimination performance. These findings establish a correlation between cellulose depolymerization and dielectric discharge behavior, providing a polymer-centered interpretation of aging mechanisms in ester-based oil–paper insulation systems. Full article

Microstructural and morphological effects of cobalt (Co), nickel (Ni), and cerium (Ce) microalloying on the SAC305 lead-free solder alloy were investigated, with emphasis on the solidification behavior under slow cooling conditions. Although the individual effects of these elements have been previously reported, their combined influence remains scarcely addressed. Thermal behavior, elemental composition, and surface integrity of the solder joints were analyzed. The addition of Co, Ni, and Ce resulted in a significant shift of the onset temperature during cooling, indicating reduced undercooling. Microalloying led to a transformation of the intermetallic layer (IML) morphology from scalloped to planar, and a 60% reduction in the number of shrinkage voids. The average β-Sn grain size decreased by 37.5%, while the eutectic area increased from 32% to 38%. The substitution of Cu atoms by Co and Ni within the Cu₆Sn₅ lattice formed thermodynamically stable (Cu,Co,Ni)₆Sn₅ phases. These findings demonstrate that the synergistic effect of Co, Ni, and Ce microadditives effectively refines the microstructure, suppresses undercooling, and enhances the overall reliability of SAC305 solder joints. Full article

This paper investigates how climate shelter initiatives implemented in European cities interact with National Adaptation Strategies (NAS) and National Adaptation Plans (NAP), assessing the degree of vertical integration between local practices and national climate adaptation frameworks. As urban heat increasingly threatens public health and exacerbates socio-spatial inequalities, climate shelters, conceived as networks of safe, accessible public spaces providing thermal comfort and social support, have emerged as innovative adaptation tools; however, their recognition within national policy architectures remains uneven across the EU. This study adopts a qualitative–comparative design structured in three phases: (i) a systematic review of NAS and NAP in the 27 EU Member States through keyword screening and classification of references as explicit, implicit, or absent; (ii) a mapping of climate shelter initiatives across 244 NUTS-2 capital cities; and (iii) an integrative cross-analysis of national frameworks and local implementation patterns. According to our results, only 4 Member States explicitly refer to climate shelters, 11 include implicit references, and 12 show no recognition, while 88 cities implement 97 initiatives, predominantly based on Nature-based Solutions and schoolyard transformations; 5 recurring governance configurations reveal bottom-up, top-down, and hybrid dynamics, demonstrating that local experimentation can anticipate, complement, and potentially reshape national adaptation policies. Full article

To enhance the early-age properties of steel slag cement mortar and promote the resource utilization of metallurgical solid waste, in this study, nano-SiO₂ (KH-NS) was modified using a KH550 silane coupling agent. The hydration kinetics and microstructure evolution were systematically analyzed by means of a macroscopic performance test (setting time and compressive strength) and multi-scale microscopic characterization (characterized by Fourier Transform Infrared Spectroscopy, Scanning Electron Microscopy, X-ray Diffraction, Thermogravimetry-Differential Thermal Analysis, and isothermal calorimetry). The influence mechanism of its content on the early performance of the steel slag cement system was systematically studied. Research findings indicate that at a given dosage, increasing the proportion of KH-NS results in a shorter setting time for steel slag mortar. When the KH-NS dosage reaches 1.5%, the initial and final setting times of steel slag mortar decrease by 24.21% and 21.20%, respectively. The addition of KH-NS effectively enhances the compressive strength of mortar, with a particularly pronounced effect on early strength prior to 14 h of curing. At a KH-NS dosage of 1.5%, the onset of the accelerated phase of hydration heat release in steel slag cement mortar is advanced by 2.5 h. Mechanistic studies indicate that KH-NS accelerates cement hydration by promoting C₃S dissolution and C-S-H gel nucleation through interactions between surface silanol groups (Si-OH) and amino groups (-NH₂). Furthermore, KH-NS refines the pore structure via a micro-aggregate filling effect, reducing the number of harmful pores and improving the pore size distribution. KH-NS continuously consumes Ca(OH)₂ through pozzolanic reactions to generate C-S-H, with its reactivity increasing with higher dosage. Research confirms that KH-NS significantly enhances the early strength and density of steel slag mortar, providing both theoretical justification and technical support for developing low-carbon building materials based on solid waste with high dosage. Full article

Since At-Turaif’s inscription as a World Heritage Site in 2010, Al-Diriyah and its peripheries have witnessed massive urban development. With the recently proposed Wadi Safar project, the expansion of Al-Diriyah has taken another turn, as it is conceptualized as a luxury driven mixed-use district, integrating cultural experiences that are rooted in the past. This research examines the urban development of Al-Diriyah through the lens of the Experience Economy Model (1998), in which value is derived not just from objects or spaces but from the memorable and immersive experiences they tend to incorporate. This study employs a qualitative-case study methodology structured through a five-phase analytical framework that spans from 2010 to 2025/2030. Utilizing a deductive qualitative approach, the analysis demonstrates a differentiated application of the four experiential realms of the Experience Economy Model across the study sites. While At-Turaif predominantly engages two experiential dimensions and the broader regeneration of Al-Diriyah incorporates three, the planned development of Wadi Safar is designed to encompass all four dimensions of the Experience Economy. This configuration produces a balanced spectrum of active and passive participation as well as absorption and immersion, positioning Wadi Safar within Al-Diriyah’s broader transformation into the world’s largest heritage-led urban development. The findings contribute to the theme of a thriving economy of KSA Vision 2030 by advancing heritage-oriented experience as a pathway towards economic diversification. Full article