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Fabrication and Characterization of Formamide-Modified Magnesium Aluminum Layered Double Hydroxide as Reinforcing Nanofiller for Thermoplastic Starch Film
No full textThermoplastic starch (TPS) is produced by processing starch at high temperatures with plasticizers like water or glycerol, transforming it into an amorphous polymer. A major issue with natural polymers is their high water permeability and tendency to swell, which weakens mechanical properties and limits direct use. Combining starch with clay in nanocomposites offers significant potential for new engineering materials. This study investigates enhancing TPS properties with formamide-modified magnesium-aluminum layered double hydroxide (MgAl LDH) nanofillers. MgAl LDH (Mg/Al molar ratio 3:1) was synthesized via co-precipitation, modified with formamide (MgAl-F LDH), and dispersed in the TPS matrix using twin-screw extrusion. Characterization techniques, including tensile testing, water contact angle, FTIR, XRD, SEM, TEM, and TGA/DTG, comprehensively examined the properties of both the fillers and the resulting nanocomposite films. The findings indicated that the modified MgAl-F LDH nanoparticles exhibited an average size of approximately 48 nm, with lower crystallinity compared to unmodified MgAl LDH (average size ~ 50 nm). The incorporation of MgAl-F LDH significantly enhanced the thermal stability and hydrophobicity of the TPS films, although a reduction in tensile strength was observed. These results suggest that formamide modification of MgAl LDH can optimize TPS composites, expanding their potential applications in packaging and biodegradable materials
From Pessimism to Subjective Well-Being in Adolescents: A Longitudinal Mediation Study of Cognitive Flexibility
No full textAdolescence is a crucial time of identity formation, scholastic and social demands, future concerns, and relationship changes. Adolescents are especially susceptible to psychological issues like pessimism, which can hinder their progress and well-being. Cognitive flexibility may help adolescents adjust to these challenges and improve subjective well-being. Pessimism, cognitive flexibility, and subjective well-being have been investigated cross-sectionally, but their longitudinal association has not. This study examines cognitive flexibility's mediation function in the longitudinal association between pessimism and subjective well-being in teenagers, taking into account their well-being development and inadequacies. This study looked at how cognitive flexibility affects the link between pessimism and subjective well-being. To address the limitations of cross-sectional mediation analysis, the current study employed an autoregressive cross-lagged panel model within a half-longitudinal framework, which allows for a more accurate estimation of directional and temporal relationships among the variables. This model used two 3-month-apart data sets. Cognitive flexibility was found to mediate the relationship between pessimism and subjective well-being (χ2 (3, N = 232) = 11.68, p < 0.001). These findings indicate that cognitive flexibility plays a significant mediating role in weakening the negative impact of pessimism on adolescents’ subjective well-being, highlighting its importance as a protective cognitive factor during this critical developmental period
EXAMINING THE RELATIONSHIP BETWEEN FOREIGN LANGUAGE ENJOYMENT, BOREDOM LEVELS ANDINTERNET ADDICTION OF LEARNERS IN EFL CLASSES
No full textBoron nanoparticle doped PVA polymer composite nanofibers: In vitro behaviors
No full textThis study aims to address the limitations associated with boron sources that contain chemical impurities and to enhance the applicability of boron (B) nanoparticle-doped polyvinyl alcohol (PVA) composite nanofibers in biomedical applications using the electrospinning technique. Morphological analyses conducted through Scanning Electron Microscopy (SEM) and Transmission Electron Microscopy (TEM) confirmed uniform dispersion of B nanoparticles, with an average fiber diameter of 185.52 ± 38.86 nm at a flow rate of 1 mL/h and an applied voltage of 9 kV. X-ray Diffraction (XRD) and TEM indicated the presence of rhombohedral crystalline B nanoparticles, while Fourier Transform Infrared Spectroscopy (FT-IR) revealed enhanced molecular interactions and the formation of new functional groups. Thermogravimetric Analysis (TGA) demonstrated an increase in the thermal stability of the PVA/B composite nanofibers. Water absorption and enzymatic degradation analyses showed that B nanoparticle doping accelerated lysozyme-induced degradation. Antibacterial activity tests exhibited distinct inhibition zones against E. coli (13.90 mm), S. aureus (6.34 mm), and C. albicans (21.30 mm). Biocompatibility evaluation using the MTT assay revealed a high cell viability rate of approximately 99.2 %, confirming the cytocompatibility of the composite fibers. Overall, the findings highlight the promising potential of PVA/B composite nanofibers as multifunctional materials for advanced wound care systems
Analytical Solutions of Nonlinear Conformable Time-Fractional CDGKS Equation via Modified Sardar Sub-Equation Method
No full textEnhanced Interfacial Adhesion in CF/PEEK Composites via rGO-Functionalized Polyimide Sizing Agent
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Architectural Perspective on The Structural Behavior in Spanning Wide Openings With Arch Forms
No full textHistorical dimensions and directions on energy storage: unique perspectives
No full textEnergy storage has become a crucial technology solution in an era marked by the urgent need to transition towards sustainable energy systems with renewable sources and energy storage systems. It facilitates the widespread adoption of these sources and ensures the reliability and resilience of energy networks. This perspective article offers a comprehensive overview of the current landscape of energy storage technologies, their diverse applications, and the challenges and opportunities that lie ahead, based on bibliographic data captured from the Scopus. The technological landscape of energy storage methods is examined, encompassing mechanical, heat, chemical, electrochemical, magnetic, and electromagnetic as potential short- and long-duration storage techniques. We discuss trend topics related to the diverse applications of energy storage, ranging from grid integration and electric vehicles to microgrids and ancillary services. Additionally, this study highlights critical research directions and technological advancements that can potentially transform the energy storage sector in the years ahead. This study further aims to provide a valuable contribution to the ongoing discussion on achieving a sustainable, reliable, and decarbonized energy future by comprehending the various aspects and predicting the future trends of energy storage
