Search Results (596)

Latent fingerprint development on rough non-porous substrates using fingerprint powders remains challenging because surface microstructures reduce particle-adhesion selectivity and weaken the contrast between ridges and the background. In this study, Cs${}_2$NaBi${}_{0.6}$Er${}_{0.4}$Cl${}_6$ double-perovskite nanoparticles were prepared by a solvothermal method and investigated as fingerprint-development particles for latent fingerprints on frosted plastic substrates. Structural characterization by X-ray diffraction (XRD), scanning electron microscopy (SEM), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS) indicated that Er${}^{3+}$ was incorporated into the host matrix and that the product consisted of spherical nanoparticles with smooth surfaces, relatively uniform particle-size distribution, and good dispersibility. Comparative experiments involving 40 categories of latent fingerprint samples showed that the Cs${}_2$NaBi${}_{0.6}$Er${}_{0.4}$Cl${}_6$ nanoparticles outperformed conventional powders in developing fingerprints on frosted plastic substrates. Quantitative grayscale analysis using Image J 1.53K and Origin 2024 further showed that the development contrast, expressed as the D value, reached 51.21 for sebum-rich fingerprints and 35.87 for oil-contaminated model fingerprints, both of which were higher than those obtained with the other three powders. Because the fluorescence of Cs${}_2$NaBi${}_{0.6}$Er${}_{0.4}$Cl${}_6$ under UV excitation was weaker than that of the commercial red fluorescent powder, we attribute the improved development performance mainly to selective adhesion of the particles to fingerprint residues rather than to fluorescence intensity alone. In addition, the material maintained good performance for aged fingerprints within 10 days and for developed fingerprints stored for up to 8 days. These results suggest that selective residue-affinitive adhesion, possibly assisted by the hydrophilic or moisture-affinitive nature of the ionic double-perovskite particles, plays an important role in improving fingerprint development on rough non-porous substrates. This study provides a physical perspective for latent fingerprint development on rough non-porous substrates and broadens the forensic-science application of lead-free double-perovskite nanomaterials. Full article

Nanotextured thin film metallic glasses (TFMGs) have emerged as promising antimicrobial coatings for biomedical applications; however, systematic comparisons across compositionally distinct Ti- and Zr-based systems, as well as their early-stage bactericidal mechanisms, remain limited. Here, we show, for the first time, a comparative, compositionally resolved correlation linking alloy chemistry, nanotexture, and bactericidal mechanisms across polymorphic TFMGs. Three co-sputtered biocompatible coatings (Ti₄₇Fe₄₁Cu₁₂, Zr₇₁Fe₃Al₂₆, and Zr₅₈W₃₁Cu₁₁) were deposited on medical-grade titanium and stainless steel (SS316L) via magnetron co-sputtering, producing uniform amorphous films (190–298 nm) with nanoscale roughness of 1.6 ± 0.05 to 8.1 ± 0.05 nm. Surface wettability spanned hydrophilic (71.1 ± 5.6°) to hydrophobic (106.5 ± 3.5°), modulating bacterial interactions. Antimicrobial performance against Pseudomonas aeruginosa was evaluated using live/dead fluorescence imaging, quantitative image analysis, and electron microscopy after 2–4 h incubation. All coatings reduced bacterial adhesion and viability relative to bare substrates, with Zr₅₈W₃₁Cu₁₁ achieving >60% reduction in surface-associated bacterial coverage. Time-resolved analysis revealed a rapid transition to predominantly non-viable populations on coated surfaces, in contrast to sustained viability on controls. Mechanistically, bactericidal activity arises from the synergistic coupling of nanotopography-induced membrane stress, wettability-governed adhesion energetics, and in situ formation of CuO, Fe₂O₃, WO₃, and ZrO₂ oxides that promote electrostatic interactions and proposed reactive oxygen species generation, driving oxidative membrane damage. These results establish a scalable design framework for TFMGs, while highlighting the need for long-term biofilm and electrochemical validation. Full article

In this study, La-doped TiO₂-SiO₂ composite films were deposited on glass substrates by radio-frequency magnetron sputtering. The evolution of microstructure and macroscopic properties was systematically investigated across an annealing temperature range of 350–650 °C. The results show that the La-doped TiO₂-SiO₂ composite structure effectively suppresses abnormal grain growth and delays the anatase-to-rutile phase transition, thereby improving the films’ high-temperature structural stability. Notably, the composite film annealed at 550 °C (LS-550) exhibits the highest anatase crystallinity and forms a dense, smooth (RMS = 1.37 nm), crack-free nanocrystalline network. In terms of wettability, the improved hydrophilicity is attributed to the combined effects of La incorporation and hydrophilic silanol (Si-OH) groups in the amorphous SiO₂ phase. As a result, the water contact angle of the LS-550 film decreases dramatically to 28.0°, indicating excellent hydrophilicity. Moreover, the LS-550 film demonstrates an optimal photocatalytic degradation efficiency of approximately 76% for methylene blue, significantly outperforming the pure TiO₂ film. Furthermore, the enhanced mechanical performance is associated with the combined effects of the SiO₂-containing amorphous phase and the finer microstructure induced by La incorporation. Consequently, the critical load (Lc) of the LS-550 film reaches 75.64 mN, significantly exceeding that of the pure TiO₂ film annealed at the same temperature (61.25 mN). In summary, the composite film annealed at 550 °C concurrently achieves high crystallographic thermal stability, robust interfacial mechanical durability, excellent surface hydrophilicity, and enhanced photocatalytic activity, thereby offering practical guidance for developing TiO₂-based coatings with self-cleaning potential for high-rise building curtain walls. Full article

This study investigated rhamnolipid synthesis in Pseudomonas aeruginosa ATCC 27853. Two constitutive promoters, P_rpsJ and P_oprL, were isolated and cloned upstream of the rhlABRI and rmlBDAC gene clusters to evaluate their impact on rhamnolipid titers. The overexpression of rhlB, driven by the P_rpsJ promoter, significantly enhanced rhamnolipid production. Subsequent glycine-scanning mutagenesis of RhlB identified an optimal variant (RhlBM328G), which increased the titer 1.82-fold (to 24.6 g·L⁻¹) compared to the wild type, achieving a product yield of 0.39 g·g⁻¹. Characterization of the extracted rhamnolipids revealed a critical micelle concentration of 1 mg/L, a corresponding surface tension of 53.9 mN/m, and a hydrophilic–lipophilic balance (HLB) value of 14. This HLB value indicated that the synthesized rhamnolipids possess superior hydrophilicity, robust oil-in-water emulsifying capabilities, and excellent solubilization and dispersion properties. Furthermore, molecular docking and molecular dynamics simulations demonstrated that in the RhlBM328G mutant, the nucleophilic attack distances between the substrates and the catalytic moiety are optimized for catalysis, thereby boosting rhamnolipid production. Full article

Hydrogels (HGs), three-dimensional cross-linked hydrophilic polymer networks, have emerged as a promising class of functional materials for sustainable agriculture due to their exceptional water retention capacity, responsiveness to environmental stimuli, and favorable biocompatibility. This review systematically summarizes the key functional properties of hydrogels and critically examines their multidimensional roles within agricultural systems. The major synergistic benefits of hydrogels are highlighted, including (1) improvement of soil physical structure, chemical properties, and the biological microenvironment, thereby facilitating soil remediation; (2) direct enhancement of seed germination, root development, and crop productivity when employed as soil amendments or seed-coating materials; (3) controlled and sustained release of water, nutrients (N, P, K, and trace elements), and pesticides, leading to significant improvements in resource use efficiency; (4) functional delivery of beneficial microorganisms, enabling precise regulation of their activity and efficacy; and (5) advancement of soilless cultivation technologies through the development of sophisticated hydrogel-based substrates. Furthermore, this review discusses the key challenges that currently limit large-scale agricultural implementation, including insufficient biodegradability, potential ecotoxicological risks, and techno-economic constraints. Finally, future research directions are proposed from an interdisciplinary perspective, emphasizing rational material design, performance optimization, and practical field application. This comprehensive review aims to provide systematic theoretical guidance and practical insights for the development and deployment of hydrogel-based technologies in sustainable agriculture. Full article

Constructing inverted wedge-shaped hydrophilic channels with a small apex angle on surfaces with wettability patterns is an effective strategy to promote efficient and complete droplet detachment, which is crucial for applications such as condensation heat transfer and self-cleaning. However, a comprehensive understanding of how wedge geometry parameters affect droplet dynamics has not been established. In this study, we systematically investigate the dynamics of droplet formation and detachment within inverted wedge-shaped superhydrophilic channels fabricated by laser etching on hydrophobic or superhydrophobic substrates. Four distinct droplet detachment mechanisms are revealed. Our results indicate that, within the experimental parameters tested, a slender channel geometry—featuring a narrow upper base, a minimized lower base, and sufficient height—combined with a superhydrophobic substrate, promotes high-position droplet formation, extends the droplet sliding distance, and significantly reduces resistance. This synergy leads to the most efficient detachment mechanism: inertia-driven direct shedding. For the tested configurations, the C1.2/0/40 channel achieved the highest recorded detachment frequency of 318 min⁻¹ at a flow rate of 0.5 mL/min. Furthermore, droplet rebound at the channel tip is observed in some configurations, where two to three droplets must form sequentially and coalesce to trigger a single detachment event. This work provides actionable geometric design strategies for engineering surfaces capable of directional and highly efficient droplet detachment. Full article

This study employs molecular dynamics simulations to investigate the condensation behavior of water molecules on hydrophilic/hydrophobic substrates under varying electric field strengths. It reveals the synergistic regulation effect between electric field strength and surface wettability from the perspectives of condensation rate and morphological evolution. The results indicate that the condensation rate on hydrophilic surfaces first increases and then decreases with increasing electric field strength; the condensation efficiency reaches its maximum at an electric field strength of 1.6 V/nm. Conversely, the condensation efficiency on hydrophobic surfaces shows a monotonically decreasing trend with increasing electric field strength; the presence of an electric field does not facilitate condensation on hydrophobic surfaces. The orientation of water molecule dipole moments is synergistically regulated by external electric fields, intermolecular interactions, and substrate–water interactions. The weaker the wettability, the more readily the electric field assumes a dominant role. Furthermore, the electric field induces parallel alignment of dipole moments along its direction, enhancing intermolecular attractions along the electric field axis (Z-axis). This also drives the reconfiguration of hydrogen-bond networks, ultimately leading to the aggregation of water molecules into clusters aligned with the electric field, thereby transforming the condensation morphology. Full article

Natural fibers are among the most extensively exploited bio-based materials in industry due to their abundance, affordability, and biodegradability. However, their intrinsic properties often require improvement through chemical, mechanical, or enzymatic treatments to expand their applications. Phosphorylation is a highly effective chemical modification that enables the covalent grafting of phosphate groups onto the fiber backbone. These functionalities enhance hydrophilicity, anionic charge density, swelling capacity, and water uptake, while significantly improving flame-retardant performance. In addition, phosphorylation can reduce energy consumption and production costs in the manufacture of functionalized micro- and nanofibrillated fibers, as the increased swelling facilitates fibrillation. Consequently, phosphorylated fibers are suitable for water treatment, biomedical devices, construction materials, and other advanced materials. Dozens of reagents and various synthetic routes have been explored to perform this reaction, each producing materials with distinct properties. Phosphorus content remains the primary parameter used to assess modification efficiency. This literature review examines existing phosphorylation methods, including reagents, substrates, and characterization techniques, and discusses applications such as flame retardancy, thermal insulation, ion exchange, energy storage, electrodes, and battery recycling. It also briefly addresses key challenges, including limited hydroxyl accessibility, control of the degree of substitution, potential cellulose degradation, and scalability constraints. Full article

To address the trade-off between storage stability and curing reactivity in NCO-terminated waterborne polyurethane (WPU) systems, a solvent-free WPU emulsion with dual-curing characteristics was developed using vanillin (VAN) and 2-hydroxyethyl acrylate/pentaerythritol triacrylate (HEA/PETA). Hexamethylene diisocyanate (HDI) and 2,2-bis(hydroxymethyl)butyric acid (DMBA) were used as the isocyanate component and internal hydrophilic moiety, respectively, to prepare a self-dispersible polyurethane prepolymer. VAN was introduced as a latent isocyanate-related component, while HEA/PETA served as acrylate-bearing reactive modifiers, followed by self-emulsification to form a stable aqueous dispersion. The prepolymer structure, curing behavior, and adhesive performance on bamboo substrates were systematically investigated. The results supported the successful introduction of VAN-derived structures into the polyurethane chains and the retention of polymerizable C=C bonds from HEA/PETA. Thermal analysis suggested dual-curing behavior with two distinguishable thermal events, involving lower-temperature polymerization of unsaturated groups and a VAN-related higher-temperature reaction. The resulting WPU exhibited dry and wet shear strengths above 23 MPa and 9 MPa, respectively. These findings demonstrate a feasible strategy for integrating emulsion stability, staged curing, and adhesive performance in solvent-free WPU systems. Full article

This study investigates the femtosecond laser surface texturing approach to tune the wetting properties of glass substrates applied for photovoltaic panels. Two types of microstructured LIPSS-containing motifs—parallel channels and intersecting (crossing) patterns—were fabricated and evaluated through comprehensive durability tests, including thermal cycling, UV exposure, chemical immersion, mechanical abrasion, and dust retention assessment. Wettability measurements showed that both textures exhibit stable hydrophilicity behavior, with the intersecting patterns exhibiting the fastest wetting dynamics; in many cases, complete surface wetting occurred within the first few minutes, preventing a measurable contact angle at later stages. The durability tests caused only minor smoothing of the textured features, and the overall micro- and nanostructures remained intact. Optical characterization revealed that the laser-induced textures maintained high transmittance with no significant degradation after environmental exposure. Overall, the results demonstrate that femtosecond laser texturing provides a robust, coating-free method for producing stable and tunable wetting behavior on glass, offering a promising pathway for the future creation of durable, highly hydrophilic self-cleaning surfaces in photovoltaic systems. Full article

This study investigates the influence of conventional textile pretreatment and periodate oxidation parameters on the structural modifications and functional properties of woven cotton fabrics. Unlike most studies focused on cellulose pulps or isolated textile fibers, the present work examines how the initial structural state of the textile substrate, determined by its pretreatment history, governs the oxidation pathways. Cotton fabrics were subjected to alkaline scouring (SC), hydrogen peroxide bleaching (BC), and combined scouring–bleaching (SBC), followed by sodium periodate oxidation under controlled conditions. Carbonyl species were quantified analytically and identified by ATR-FTIR spectroscopy, while structural changes were evaluated by X-ray diffraction (XRD). Mechanical properties were assessed using the normalized parameters (Fa/Fa₀ and E/E₀), hydrophilicity by water absorption capacity (WAC), and optical stability by the yellowness index (YI). The results demonstrated that the pretreatments influence the oxidant accessibility and the balance between carbonyl speciation. XRD analysis shows a moderate decrease in crystallinity, indicating partial preservation of the crystalline domains, whereas mechanical properties decrease significantly (35–65%), concomitant with a 25–45% reduction in WAC. These results suggest that the impairment in mechanical and hydrophilic properties is primarily governed by localized C2–C3 bond scission, secondary oxidative reactions, and supramolecular rearrangements, rather than by bulk crystalline loss. The oxidized SC series exhibits higher YI values associated with an increased free aldehyde content, while the BC and SBC fabrics show improved optical stability. Overall, these results demonstrate that pretreatment history governs periodate oxidation pathways and establishes clear structure–property relationship relevant for the controlled functionalization of woven cotton fabrics. Full article

Titanium implants are widely used in orthopedic and dental fields but often face challenges such as insufficient osseointegration and peri-implant inflammation. While Strontium (Sr) possesses potent bioactive properties, achieving its controlled delivery at the implant-tissue interface remains technically challenging. To address this, we engineered a multidimensional composite coating by constructing a micro/nano-porous TiO₂ substrate via micro-arc oxidation (MAO), followed by polydopamine (PDA)-assisted Sr immobilization. This integrated architecture significantly enhanced surface hydrophilicity and facilitated high-content Sr loading with sustained release kinetics. Biological evaluations demonstrated that the PDA-mediated interface promoted superior initial adhesion and spreading of bone marrow mesenchymal stem cells (BMSCs), synergizing with released Sr²⁺ to markedly upregulate core osteogenic markers (Runx2, ALP). Crucially, the functionalized surface actively optimized the immune microenvironment by inducing M1-to-M2 macrophage polarization and comprehensively suppressing RANKL-induced osteoclastogenesis via the downregulation of TRAP and DC-STAMP. By integrating these pro-osteogenic, anti-inflammatory, and anti-resorptive capabilities, this tri-functional system effectively rebalances the bone remodeling microenvironment. Consequently, it provides a robust, universally applicable strategy for enhancing the therapeutic efficacy of next-generation orthopedic and dental implants. Full article

Uranium is a critical raw material for the nuclear industry. Given the vast uranium reserves in seawater, the development of efficient adsorbents is central to extraction technologies. Polyamidoxime (PAO)-based adsorbents are widely utilized due to their high affinity for uranium; however, traditional PAO materials often suffer from low mechanical strength and poor recyclability. To address these limitations, this study utilized natural balsa wood as a substrate. A three-dimensional porous cellulose skeleton (DES-W) featuring high porosity, hydrophilicity, and retained mechanical strength was constructed by partially removing lignin using a deep eutectic solvent (DES). Subsequently, polyamidoxime was loaded onto the inner walls of the DES-W via vacuum impregnation, resulting in a polyamidoxime-functionalized wood-based adsorbent (PAO-WA). The results indicated that PAO-WA achieved an equilibrium adsorption capacity of 45.31 mg/g at pH 6.0 with an initial uranium concentration of 50 mg/L, representing a twofold increase compared to the unmodified DES-W. The adsorption kinetics and isotherms followed the pseudo-second-order and Langmuir models, respectively, suggesting a mechanism dominated by monolayer chemisorption. Mechanism analysis confirmed that uranyl ions were primarily captured via coordination with nitrogen and oxygen atoms in the amidoxime groups, with residual carboxyl groups in the wood contributing to the adsorption process. This work offers a novel strategy for developing efficient, environmentally friendly, and mechanically robust adsorbents for uranium extraction from seawater. Full article

Bioadhesive materials capable of operating under aqueous conditions are of considerable interest for biomedical and materials science applications. Peptide-based systems represent an attractive platform for such materials due to their structural tunability, inherent biocompatibility, and ability to form supramolecular networks through noncovalent interactions. In this work, a focused library of tyrosine-containing dehydropeptides was designed and synthesized to investigate how molecular architectures influence self-assembly, hydrogel formation and adhesive properties. The peptides were synthesized using a solution-phase Boc strategy and systematically varied with respect to N-terminal protection and C-terminal functionality. The N-protected dehydropeptides formed supramolecular hydrogels through multiple gelation triggers, including pH reduction and heating–cooling cycles. Rheological characterization confirmed the formation of viscoelastic networks with tunable mechanical properties, with storage moduli reaching tens of kilopascals depending on peptide structure. Scanning electron microscopy revealed dense fibrous nanostructures consistent with supramolecular hydrogel formation. The N,C-deprotected dehydropeptides displayed reduced gelation propensity but formed cohesive films with measurable adhesive performance toward hydrophilic substrates. Lap-shear tests demonstrated high shear strengths for the hydrophilic films, highlighting their structural robustness under stress. Overall, this study provides insights into the structure–property relationships governing tyrosine-containing dehydropeptide assemblies and demonstrates their potential as minimalistic building blocks for supramolecular adhesive materials. Full article

This work explores, for the first time, a novel strategy for the preparation of polymer inclusion membranes (PIMs) based on their deposition onto porous supporting substrates, introducing the concept of supported PIMs as a reagent-efficient alternative to conventional free-standing membranes. The approach aims to improve the sustainability of PIM fabrication by significantly reducing the amount of polymer and extractant required while preserving membrane functionality. PIMs were prepared using the two most widely employed base polymers, cellulose triacetate (CTA) and poly(vinyl chloride) (PVC), with Aliquat 336 as extractant. The total reagent consumption was reduced to half of the conventional formulation for CTA-based membranes and to one quarter for PVC-based membranes. Two porous supports with contrasting physicochemical properties—a hydrophilic cellulose filter paper and a hydrophobic Durapore^® PVDF membrane—were investigated. The supported membranes were characterized by contact angle measurements, SEM, FTIR, and TGA, confirming the successful integration of the PIM phase onto the porous supports without chemical alteration. Arsenate (As(V)) transport, preconcentration, and membrane reusability were evaluated. CTA-based supported PIMs exhibited transport efficiencies of approximately 90–95%, comparable to free-standing PIMs, whereas PVC-based systems showed a stronger dependence on membrane loading. Notably, CTA-based Durapore^®–PIMs retained around 70% transport efficiency after three reuse cycles. These results demonstrate the feasibility of supported PIMs as a strategy for reducing membrane material consumption while preserving functional performance. Full article