Search Results (6,541)

Innovations in nanomaterial science, engineering and printing technologies have increasingly driven advances in electrochemical sensing. Screen-printed electrodes (SPEs) have become a versatile, low-cost, and scalable solution for developing portable electrochemical detection platforms. However, their analytical performance remains intrinsically limited by surface area, electron transfer efficiency, and the immobilization of biomolecules. Recent developments in nanostructured materials, ranging from two-dimensional (2D) materials such as graphene, MXenes, and transition metal dichalcogenides, to one-dimensional nanostructures and hybrid nanocomposites, have transformed the signal transduction landscape of SPE-based electrochemical sensors. Integration of nanomaterials into SPEs has successfully transformed their analytical capabilities, but the diversity of materials and modification strategies has made it difficult to consolidate current knowledge in the field. Strategies that integrate nanomaterials via ink formulation, surface modification, or in situ growth have yielded sensors with unprecedented sensitivity, reproducibility, and selectivity across various chemical and biological targets. This review offers a cross-material synthesis of how nanomaterial engineering transforms the electrochemical performance of SPEs. By integrating insights across morphology, interfacial chemistry, and device-level behavior, it establishes a unified perspective that has been missing from the current literature and clarifies the design principles driving next-generation SPE-based sensing platforms. Full article

The multilayers of Ta/Pd/[CoFeB (0.3 nm)/Pd]×5/Pd films were fabricated by ultra-high-vacuum (UHV) magnetron sputtering and subsequently annealed at temperatures (T_A) ranging from 100 °C to 400 °C. The magnetic measurements were performed with the applied field oriented parallel and perpendicular to the film plane to evaluate the out-of-plane magnetic anisotropy (PMA). A maximum effective PMA energy density (K_eff) of ≈7.82 × 10⁵ erg/cc and a small out-of-plane saturation magnetisation (M_s⊥) were achieved at the optimal T_A. The evolution of PMA is associated with interfacial atomic migration and oxidation processes, as confirmed by X-ray photoelectron spectroscopy (XPS). Annealing at 300 °C initiates the formation of TaB and TaOB interfacial phases, whereas annealing at 400 °C promotes the enhanced growth of Ta₂O₅ and TaB, along with additional TaOB formation owing to increased oxygen migration. These thermally stable Ta–boride phases lead to pronounced modifications in the magnetic properties. Consequently, oxygen migration and interfacial reactions at elevated temperatures primarily alter the chemical states of the B 1s, Pd 3d, and Ta 4f orbitals, thereby influencing the PMA. The field-dependent electrical resistance (MR) study demonstrates that annealing at 100–400 °C optimises the anisotropic effect in the [CoFeB/Pd]×5-based multilayers. However, higher temperatures can trigger atomic intermixing, which degrades PMA strength and the resistance response. Moreover, the samples were further characterised by their structural, anomalous Hall effect (AHE) and magnetoresonance (MRO) properties. Overall, controlled T_A-driven oxygen diffusion and interfacial oxidation enable effective tuning of the PMA, MR, and MRO properties of ultrathin [CoFeB/Pd]×5 multilayers, highlighting their strong potential for spin–orbit torque (SOT), Dzyaloshinskii–Moriya interaction (DMI), and magnetic skyrmion-based spintronic devices. Full article

Climate warming in Mediterranean vineyards accelerates grape ripening and increases the incidence of sunburn and berry shriveling, leading to imbalances in grape composition and wine quality. This study evaluated the combined effects of a non-positioned training system (asymmetric sprawl) and foliar application of kaolin particle film on vine microclimate, agronomic performance and wine aroma profile in a Syrah cv. vineyard under warm conditions. Vine canopy temperature was monitored by UAV thermography at veraison and harvest, while grape damage, yield components and vegetative balance were assessed at harvest. Wines obtained from each treatment were analysed for chemical composition, volatile compounds and sensory attributes. Kaolin application significantly reduced canopy temperature, particularly under water-limited conditions at veraison (up to 1.9 °C), and the combination with sprawl training decreased the proportion of sunburnt and shrivelled clusters. These microclimatic modifications were associated with higher ethanol content, improved colour intensity and increased total polyphenol index in wines. The combined strategy also enhanced the concentration of key aroma compounds, especially terpenes and fruity esters, resulting in higher values of citrus, floral and fruity aromatic series. Sensory evaluation confirmed a better overall appreciation of wines produced from vines managed with both practices. Overall, the integration of canopy architecture modification and reflective particle film represents an effective strategy to mitigate heat stress effects in warm viticultural regions, improving grape physiological performance and contributing to the preservation of wine aromatic quality under climate change scenarios. Full article

Alkaloids are structurally diverse, nitrogen-containing plant secondary metabolites with well-documented insecticidal activity. This review examines alkaloid-based insecticides, focusing on their chemical diversity, biosynthetic origins, plant distribution, and physicochemical properties relevant to pest control on farms. The principal molecular targets and modes of action are discussed, including interactions with nicotinic acetylcholine receptors, acetylcholinesterase, ryanodine receptors, and GABAergic signaling. Another focus is key metabolic enzymes, together with their activity spectra against major agricultural pests. Recent advances in rational structural modification, supported by crystallographic data, computational modeling, and structure–activity relationship studies, are highlighted as strategies to enhance the potency, selectivity, and stability of these compounds. Toxicological profiles, food residue behavior, analytical challenges, and regulatory considerations are critically assessed, emphasizing that natural origin does not equate to inherent safety. The review further evaluates the role of alkaloid-based insecticides within integrated pest management systems and identifies key research gaps related to environmental safety, non-target effects, and regulatory development and harmonization. It concludes that alkaloids are positioned as potentially valuable tools for sustainable agriculture when deployed within science-based regulatory frameworks and integrated control strategies. Full article

Background/Objectives: Longer oligoarginines are very effective cell-penetrating peptides. It has been shown that a minimal number of positively charged side chains is necessary for efficient cellular uptake. But a highly positively charged peptide may interact with its cargo molecule, thereby reducing its efficiency. Several chemical modifications were tested to improve the internalization of short tetraarginine derivatives. Aromatic groups, such as Dabcyl at the N-terminus, Trp in the sequence, and AMBA or PABA in the backbone, were used to improve internalization. The other useful modification was the aza-glycine substitution in the case of penetratin. Methods: In this study, the effect of aza-glycine insertion into the peptide Dabcyl-RRRRK(Cf) on internalization was studied and compared with that of the Trp-modified peptide Dabcyl-RRWRRK(Cf). To explain the noticed difference in the biological activity of peptides, DFT calculations and the prediction of membrane-binding free energy (ΔΔF) from a peptide sequence were performed. Results: It turned out that the position of the aza-glycine moiety does not have an influence on the cellular uptake. The aza-glycine-containing peptide showed higher internalization than the Dabcyl-RRRRK(Cf) peptide. Besides this, these peptides have similar or higher cellular uptake than that of octaarginine at lower concentrations (c < 2 µM). The aza-glycine affected not only cellular uptake but also the entry mechanism. The structure of peptides depended on the amino acids (Trp, Gly, or azaGly) in their sequences and their positions. Conclusions: These may result in the different amphiphilicity of peptides, and thus changes in the hydrophobic moment and in the binding affinity of peptides to the negatively charged membrane surface. Full article

Conventional rubber–plastic modified asphalt often suffers from poor compatibility and thermal storage stability, which limits its engineering application. To address this issue, this study proposes a prefabricated nano-reinforced rubber–plastic thermoplastic elastomer (TPE) modification strategy. The specific objective was to comparatively investigate how different waste plastic matrices (HDPE, LDPE, and PP) and two representative nano-oxides (ZnO and TiO₂) affect the interfacial evolution, storage stability, rutting resistance, fatigue durability, and low-temperature cracking resistance of modified asphalt. The prefabricated nano-reinforced TPE modifier was incorporated into the base asphalt, and its storage stability, interface evolution and multi-scale rheological properties were evaluated. The results show that all modified binders exhibited good thermal storage stability, with softening point differences below 2.5 °C. The enhancement mechanism was mainly governed by physical blending, swelling adsorption, and interfacial synergistic interactions rather than the formation of new chemical functional groups. A clear synergistic matching relationship between plastic type and nanoparticle type was identified. LDPE-based systems showed better phase compatibility and fatigue/low-temperature performance, whereas HDPE-based systems were more favorable with respect to improvement of high-temperature rutting resistance. In addition, ZnO contributed more significantly to storage stability, rutting resistance, and fatigue resistance, while TiO₂ was more beneficial for low-temperature crack resistance. These findings provide new insight into the interfacial design of nano-reinforced rubber–plastic modified asphalt and offer guidance for performance-oriented and sustainable pavement materials. Full article

Water pollution, caused by selenium contamination, is a significant global issue due to its toxic effects on humans and animals. Selenium occurs in several oxidation states, among which selenite and selenate are the most mobile and bioavailable forms. Traditional water treatment methods are often limited in efficiency, whereas adsorption offers a simple, cost-effective, and efficient solution. Various adsorbents, including metal and mineral oxides, carbon-based materials (activated carbon, graphene oxide), biosorbents, and nanocomposites, have shown high potential for Se removal. Adsorbent modifications—physical, chemical, or composite—significantly enhance adsorption capacity, selectivity, and material stability. Studies have demonstrated that nanomaterials and nanocomposites, such as MnFe₂O₄, PAA-MGO, magnetic MOFs, and magnetite-based biochars, enable rapid removal of Se(IV) and Se(VI) with high adsorption capacities. Se(IV) is primarily adsorbed through innersphere complexation, while Se(VI) forms weaker outer-sphere interactions, explaining differences in removal efficiency. Factors such as pH, the presence of surface hydroxyl and amino groups, surface charge, and competing ions strongly influence the adsorption process. Multivalent ions reduce Se adsorption efficiency, whereas monovalent ions (NO₃⁻ and Cl⁻) have minimal impact. Modified adsorbents, nanomaterials, and nanocomposites provide sustainable and practical solutions for selenium removal from water, combining high efficiency, selectivity, and reusability, making them suitable for real-world water treatment applications. Full article

With the rapid intensification of industrial and agricultural activities, water contamination by heavy metal ions has emerged as a critical global challenge, gravely imperiling ecosystem stability and public health. Among the various remediation technologies, adsorption has been widely adopted due to its high efficiency, low-cost water treatment, and simplicity of operation. However, conventional inorganic or synthetic adsorbents often exhibit poor degradability and pose a risk of secondary contamination, substantially limiting their sustainable application. Consequently, the development of environmentally benign and renewable adsorbent materials has become a central research focus in this field. Recently, cellulose-based composite hydrogels, derived from renewable resources and characterized by excellent eco-friendliness and highly tunable three-dimensional porous structures, have attracted considerable attention as promising green adsorption materials. These hydrogels demonstrate outstanding performance in the efficient sequestration of heavy metal contaminants from aqueous environments. This review systematically summarizes recent advances in cellulose-based composite hydrogels for heavy metal removal, to elucidate the structure–performance relationships linking material fabrication strategies, structural modulation, and adsorption efficiency. First, we outline the principal construction approaches, including physical crosslinking, chemical modification, and supramolecular self-assembly, and comprehensively analyze how different synthesis routes regulate pore architecture, mechanical properties, and the distribution of surface functional groups. Second, the underlying adsorption mechanisms, primarily coordination complexation, electrostatic interactions, and ion exchange, are discussed in detail. Finally, recent studies on the adsorption of cationic heavy metals (e.g., Pb(II), Cu(II), and Cd(II)) and anionic oxyanions (e.g., As(III) and Cr(VI)) are critically reviewed, with particular emphasis on the relationships between selective adsorption performance, material design principles, and specific recognition mechanisms. Overall, this review provides a theoretical foundation and practical guidance for the design and development of next-generation water treatment materials with high adsorption capacity, excellent selectivity, non-toxicity, and strong environmental compatibility, followed by future research recommendations. Full article

This study examines the physical and mechanical properties of pedunculate oak (Quercus robur L.) wood samples taken from historical trabaccolo ship Carmen during restoration. The research is based on a methodological approach typical of conservation–restoration practice, in which only a limited number of samples can be taken to preserve the authenticity and integrity of the original material. Two groups of samples were analyzed visually: preserved (bright) wood and wood showing cross-sectional discoloration (dark). Physical properties (color, moisture content, density, porosity and swelling) and mechanical properties (compressive strength, bending strength and modulus of elasticity) were determined according to relevant ISO standards and chemical changes in the wood structure (FT-IR). FT-IR analysis revealed progressive degradation of hemicelluloses and oxidative modification of lignin, which was particularly significant in dark wood samples. The results of tests of physical properties indicate that dark samples exhibit higher moisture content (13%), lower density (about 7%) and greater porosity compared to preserved samples (bright wood). The compressive strength of the bright specimens was 38.3% higher than that of the dark specimens, suggesting reduced mechanical performance of the altered wood. The bending strength and modulus of elasticity of the preserved samples (bright wood) corresponded to literature data for recent oak wood. Full article

This study presents unique polymeric materials applicable to plastic substrates for use in flexible-display devices that overcome the trade-off between low linear coefficients of thermal expansion (CTE) and low thickness-direction birefringence (Δn_th) while combining a very high T_g, sufficiently high thermal stability, excellent optical transparency, good solubility, and minimum-required ductility. Polyimide (PI) films obtained from 1,2,3,4-cyclobutanetetracarboxylic dianhydride (CBDA) with 2,2′-bis(trifluoromethyl)benzidine (TFMB) under different conditions resulted in widely varying CTE values and provided a clear CTE–Δn_th correlation, which can be regarded as a virtual lower boundary in the CTE–Δn_th relationship for various PI systems. The pristine CBDA/TFMB and CpODA/TFMB (CpODA = norbornane-2-spiro-α-cyclopentanone-α′-spiro-2″-norbornane-5,5″,6,6″-tetracarboxylic dianhydride) systems were modified using numerous specifically designed monomers, i.e., a vertical-alignment-type liquid-crystalline diamine and cardo-type and spiro-type monomers. However, it was very challenging to overcome the trade-off between low CTE and low Δn_th, that is, to significantly exceed this lower boundary by modifying the pristine systems, while ensuring other target properties. One of the keys to achieving the present goal was compatibility with chemical imidization or one-pot polymerization processes (i.e., high solubility of the PIs), because these processes were more advantageous in reducing CTE and enhancing film transparency than the conventional two-step process. The modifications using phenyl-substituted xanthene-pendant 2,7-diaminofluorene and fluorene-pendant 2,3,6,7-xanthenetetracarboxylic dianhydride exhibited a prominent effect on overcoming the trade-off without the help of any fillers, while combining other excellent target properties. Polarized FT-IR difference spectra measured at varying incidence angles suggested that these side groups, which are connected perpendicularly to the PI main chains, align in the Z-direction, rationalizing the observed prominent effect. Thus, unique high-temperature transparent materials applicable to plastic substrates were successfully obtained in this study. Full article

Microwave technology is being used increasingly in polymer processing, where significant time and energy savings have been demonstrated across many systems. In this work, we first provide an overview of microwave-assisted processes involving agro-based materials, with emphasis on microwave-assisted modification reactions and extractions. A more detailed review then highlights several examples from the authors’ laboratories. For example, microwave heating has been shown to greatly accelerate the synthesis of cellulosic derivatives from cellulose and the formation of a polyurethane from a carbohydrate and a diisocyanate, while still producing polymers comparable in structure to those obtained by conventional heating. Likewise, microwave treatment can speed up pericyclic reactions involving triglycerides and cardanol, leading to products with enhanced viscosity. In extraction applications, such as recovering phenolic compounds from common beans, microwave methods can sometimes yield higher extraction efficiencies. Beyond time and energy savings, the reduced processing duration also decreases workers’ exposure to chemicals and solvents, thereby improving safety and lowering chemical hazards. Thus, microwave treatment can be considered a “green”, energy-efficient tool for many polymer reactions and processes. Full article

The increasing demand for sustainable agriculture has intensified interest in beneficial microbes as eco-friendly alternatives to chemical pesticides for plant disease control. Among these, plant growth-promoting rhizobacteria (PGPR) have attracted great interest because they can suppress plant pathogens and strengthen plant health through molecular mechanisms. Recent studies suggest that PGPR protect plants from disease not only by directly attacking pathogens but also by changing how plant immune genes are expressed through epigenetic processes. This review brings together current knowledge on epigenetic regulation in plant–PGPR interactions, focusing on DNA methylation, histone modifications, and non-coding RNA pathways. PGPR colonization activates plant immune signaling through pattern recognition receptors, MAPK cascades, reactive oxygen species, and plant hormones. The review also covers the range of bacterial signals—including lipopolysaccharides, flagellin, cyclic lipopeptides, and volatile organic compounds—that prepare plant defenses, and explains how the recognition of these signals reshapes chromatin structure at defense genes. In addition, the review discusses how these changes may influence induced systemic resistance and examines emerging, though still limited, evidence on whether they could potentially be transmitted to subsequent generations. A better understanding of how microbial signals regulate host epigenetics may reveal new ways to improve plant immunity and balance growth with defense. Overall, available evidence indicates that PGPR-induced epigenetic changes represent a promising and environmentally friendly approach to crop protection; however, field-level validation and mechanistic confirmation in non-model crop species remain necessary before this strategy can be considered practically applicable. Full article

This study investigated the effect of post-silanization processing on the surface chemistry and dispersion stability of 3 mol% yttria-stabilized tetragonal zirconia polycrystal (3Y-TZP) nanoparticles intended for the reinforcement of dental photopolymer resins. The nanoparticles were silanized using 3-Methacryloxypropyltrimethoxysilane and subjected to different post-treatment protocols, including control, drying, and centrifugation. Particle morphology was examined using field-emission scanning electron microscopy (FE-SEM) and transmission electron microscopy (TEM). Dispersion behavior was analyzed by dynamic light scattering (DLS) and zeta potential measurements, performed in triplicate (n = 3), while surface chemical modifications were evaluated using Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS). Post-silanization processing significantly influenced nanoparticle surface chemistry and dispersion stability. Centrifugation promoted the formation of Si-O-Zr and Si-O-Si linkages, reduced loosely adsorbed silane species, decreased particle agglomeration, and increased zeta potential magnitude, resulting in a more uniform hydrodynamic size distribution compared to the dried group (Z-average » 814 nm, PDI » 0.44). These findings suggest that post-silanization centrifugation acts as an interfacial selection mechanism that distinguishes covalently grafted silane from weakly adsorbed species. Within the limitations of this in vitro study, further investigations under varied conditions are required to confirm broader applicability. Full article

Groundwater–surface water interactions in volcanic hydrogeological systems represent a key process in river dynamics and were preliminarily investigated along a river draining the southern sector of the Sabatini Mountains (central Italy) using an integrated hydrogeological and geochemical approach. Serial discharge measurements, combined with physico-chemical parameters, major ions, stable oxygen isotopes, and radon analyses, reveal marked spatial variability in river–aquifer exchanges along distinct river reaches. The Arrone River exhibits clear differences between upstream, intermediate, and downstream sections, reflecting the relative influence of localized anthropogenic inputs, diffuse groundwater discharge from the volcanic aquifer, and subsurface flow contributions. Upstream reaches are characterized by pronounced modifications in discharge and chemistry, whereas intermediate and downstream reaches show progressive groundwater influence, resulting in distinct geochemical signatures and changes in water quality. Correlation and cluster analyses identify reach-specific processes controlling water composition and support the recognition of gaining and mixed river conditions under varying hydrological regimes. These results constrain a conceptual model in which river behavior is governed by spatially heterogeneous groundwater inflows, modulated by seasonal discharge dynamics and local human pressures. This study highlights the importance of reach-scale investigations for understanding SW–GW interactions in volcanic settings and provides transferable insights relevant to groundwater-dependent river systems. Full article

This study investigates the effect of chemical modification of xylite—a fraction derived from Polish lignite—using succinic anhydride (SA) on the morphology and mechanical performance of isotactic polypropylene (iPP) composites. Xylite was incorporated at loadings of 1, 10, and 25 wt% and in two particle size ranges (40–63 µm and 63–125 µm), with and without SA (0.5 and 2 wt%). The composites were characterized by wide-angle X-ray scattering (WAXS), Fourier-transform infrared spectroscopy (FTIR), and tensile testing to evaluate crystallinity (Xc), β-phase content (kβ), and mechanical properties. Unmodified xylite reduced crystallinity (Xc down to ~37%) and significantly decreased ductility, with elongation at break strongly negatively correlated with filler content (r ≈ −0.68), indicating poor dispersion and weak interfacial adhesion. In contrast, SA addition (0.5–2 wt%) partially restored crystallinity (up to ~48%) and increased stiffness (Young’s modulus up to 2120 MPa), while altering β-phase content. FTIR analysis indicated reduced intermolecular hydrogen bonding between xylite surface hydroxyl groups in the presence of SA, consistent with interfacial chemical interactions, likely via esterification. The β-phase content showed a moderate positive correlation with xylite loading (r = +0.43) and a negative correlation with elongation at break (r = −0.46), suggesting that excessive β-phase formation may reduce toughness. Larger particles (63–125 µm) provided slightly improved elongation at break and stiffness. Overall, SA acts as both a compatibilizer and a morphology-directing agent, enabling precise control of the stiffness–ductility balance and crystalline structure in iPP/xylite composites. These results establish chemically modified lignite-derived fillers as a viable strategy for engineering cost-efficient polyolefin materials with tunable structure–property relationships, offering strong potential for scalable industrial implementation. Full article