Search Results (1,260)

Superhydrophobic surfaces are typically achieved through the synergistic integration of appropriate nanostructures and low-surface-energy chemical compositions. This study presents a novel and facile method for constructing a superhydrophobic hierarchical structure directly on a pristine selective laser melting (SLM) titanium surface. The intrinsic partially melted Ti particles, which are inherent to the SLM fabrication process, were strategically utilized as a natural microscale template for the in situ growth of TiO₂ nanotubes via electrochemical anodization. Three distinct micro/nano-topographies were successfully fabricated, integrating the spherical microparticles with either conventional TiO₂ nanotube arrays or separated nanotube arrays. The results demonstrate that the resulting superhydrophobic behavior can be effectively regulated by two key factors: the liquid–solid contact mode at the microscale and the strength of capillary action within the nanostructures. Notably, these characteristics can be tailored by controlling the nanotube diameter and intertubular spacing. These findings contribute to a deeper understanding of the role of micro–nano hierarchical structures in engineering superhydrophobic surfaces, thereby opening new avenues for advanced applications. Full article

Multiscale interface engineering has influenced the engineering of orthopedic and dental implants through the integration of macroscale architecture, micro-textured surfaces and nanoscale bio-cues. These characteristics help to increase mechanical stability and support early biological responses, as well as increase resistance to microbial colonization. Multiscale interface engineering also helps to explore fabrication schemes that facilitate load-sharing lattices and micro-roughened attachment zones, as well as immune-interactive nano-chemistry. In this study, the biological responses of protein adsorption, osteogenic differentiation, connective-tissue sealing, and macrophage polarization are investigated, together with functional barriers in stress transfer, fatigue resistance and biofilm control. New clinical data with regard to arthroplasty and dental implantology are reviewed to put these factors into perspective. Even though engineered surfaces are reliable in promoting early fixation and initial osseointegration, in the long term, their performance depends on the host’s biological variability, the mechanical forces of loading, coating integrity and peri-implant microbial pressure. Altogether, multiscale interface engineering is an evolving approach to enhancing the lifespan of implants and facilitating biologically sound skeletal and oral reconstruction. A structured literature search was conducted using PubMed, Web of Science, Scopus, and Google Scholar to identify studies published between 2000 and 2025. Approximately 320 articles were initially identified, of which about 140 relevant publications were selected for detailed review. Full article

Dental implants have become common for restoring function and aesthetics after edentulism, with titanium (Ti) remaining the most widely used material due to its excellent mechanical properties and biocompatibility. Despite their clinical success, long-term performance is strongly influenced by surface characteristics, which regulate osseointegration and susceptibility to bacterial colonisation. Consequently, surface modification approaches have become critical strategies to enhance implant stability, bioactivity and longevity. This review critically evaluates conventional, advanced, and hybrid surface modification strategies. Subtractive methods, such as sandblasting and acid etching, increase microroughness (Ra 1.5–3 μm), enhancing osteoblast attachment and differentiation, but may promote bacterial adhesion and surface contamination. Combined treatments like SLA and SLActive generate hierarchical micro–nano topographies, improving protein adsorption, early-stage osteoblast proliferation (up to 2-fold), and clinical stability. Laser ablation and photofunctionalisation further modulate surface chemistry and wettability, accelerating osseointegration and epithelial cell adhesion. Coating approaches, including layer-by-layer self-assembly, nanospray drying, plasma spraying, and piezoelectric nanocomposites, introduce antimicrobial activity (>95% reduction in Escherichia coli or Staphylococcus aureus) and enhanced osteogenic differentiation with mechanical stability, with adhesion values reaching 49 MPa. Hybrid techniques such as sol–gel, hydrothermal, and anodisation provide controlled topography, chemical composition, and bioactivity, promoting early bone-to-implant contact (BIC increase of 10%–25%) in preclinical models. Notwithstanding promising in vitro and in vivo outcomes, variability in processing parameters and limited standardisation restrict large-scale clinical translation. Overall, contemporary Ti surface engineering emphasises a synergistic balance of topography, chemistry, wettability, and hierarchical structuring to optimise biological performance for dental implant applications. Full article

To address critical challenges in marine oil spill remediation, including limited penetration of high-viscosity crude oil and inefficient adsorbent recovery, it is imperative to develop environmentally friendly materials integrating high-efficiency adsorption, in situ viscosity reduction, and controllable recovery. In this study, a delignified corn pith (CPDL) with a three-dimensional porous structure was employed as a green matrix. Through constructing a Fe₃O₄/expansible graphite (EG)/polyvinylidene fluoride (PVDF) composite functional coating combined with silanization modification, a multifunctional biomass-based oil sorbent (Fe₃O₄/EG/PVDF-CPDL) was successfully fabricated. The material maintains the inherent porous architecture while forming a stable micro/nano-rough surface, exhibiting excellent superhydrophobicity with a water contact angle of approximately 155°, and demonstrating exceptional stability in harsh acidic/alkaline/saline environments and multiple cycles. Benefiting from the synergistic photothermal effect of Fe₃O₄ and EG, under one sun illumination (1 kW/m²), the material surface temperature rapidly reaches above 80 °C within 100 s, reducing the viscosity of high-viscosity crude oil by over 95% (from 1.39 × 10⁵ to approximately 6.0 × 10³ mPa·s), thereby enabling rapid penetration and adsorption within 50 s. Moreover, the composite coating significantly enhances mechanical performance, achieving a compressive strength of 320 kPa (approximately eight times higher than that of the pristine substrate), ensuring structural integrity during handling and compression recovery. Meanwhile, the material demonstrates precise directional manipulation and efficient recovery through external magnetic fields due to its superior magnetic responsivity. Experimental results reveal a broad-spectrum adsorption capacity (14.8–30.2 g/g) and separation efficiency exceeding 96% after 20 adsorption–desorption cycles. In summary, this work presents an innovative strategy with significant application potential for efficient and controllable remediation of marine oil spills, particularly high-viscosity crude oil, by integrating synergistic functions of porous adsorption, superhydrophobic corrosion resistance, photothermal viscosity reduction, mechanical reinforcement, and magnetic control. Full article

A compliant constant-force mechanism (CCFM), known for its frictionless, contact-free operation and inherently constant output, is typically limited to a single force range, restricting its adaptability to multi-task applications. To address this problem, in this study, we propose a dual-stage compliant constant-force mechanism (DSCCFM) that delivers a continuous dual-range constant-force output within a monolithic structure. The design integrates a Z-shaped beam with a bistable beam and a bistable rhombic beam, thereby forming the DSCCFM. By integrating the pseudo-rigid-body model (PRBM) with the chained-beam constraint model (CBCM), a theoretical model of the DSCCFM is established. Using a finite-element response surface model and multi-objective genetic algorithm (MOGA) optimization, the constant-force stroke was improved by approximately $38\%$ over the initial design. The experiments confirm stable outputs of 6.72 N and 21.91 N across the 2–5.8 mm and 11.6–14.8 mm ranges, respectively. The DSCCFM effectively supports multi-stage force execution, cell gripping, and micro/nano-scale manipulation. 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

Sustainable materials are increasingly being incorporated into high-strength concrete (HSC) to reduce environmental impact while maintaining structural performance. This study experimentally investigates the combined use of steel scale waste (SSW) as a replacement for natural fine aggregates and graphite nano/micro platelets (GNMPs) as a nano-modifying additive in HSC. Natural sand was replaced with SSW at levels of 0%, 50%, and 100%, while GNMPs were incorporated at dosages of 0%, 0.1%, 0.3%, and 0.5% by weight of cement. The results indicate that partial replacement of sand with SSW significantly improves concrete density and mechanical performance due to enhanced particle packing and the high specific gravity of steel scale particles. At the nanoscale, GNMPs contribute to pore refinement, improved nucleation of hydration products, and crack-bridging within the cement matrix, thereby strengthening the interfacial transition zone and delaying crack propagation. The combined effect of these mechanisms produces a synergistic enhancement in concrete performance. The optimum mixture containing 50% SSW and 0.3% GNMPs achieved a compressive strength of 68.2 MPa and splitting tensile strength of 7.6 MPa, representing improvements of approximately 54% and 52%, respectively, compared with the control mix. Durability-related properties such as water absorption and sorptivity were also significantly improved due to matrix densification and pore structure refinement. Although the incorporation of SSW and GNMPs reduced workability, all mixtures remained within a practical range for casting. The developed concrete is particularly suitable for structural applications requiring high strength and durability, such as high-rise building components, bridge elements, and precast structural members. The findings demonstrate that the combined use of industrial steel waste and nano-reinforcement offers a promising pathway toward sustainable and high-performance concrete. Full article

Epoxy resin (E-51) exhibits excellent adhesion and is widely used in the preparation of functional composite coatings. However, its smooth surface lacking micro/nano composite structures limits its self-cleaning capability and optical properties. Direct incorporation of organic silicone or inorganic fillers often faces severe phase separation and filler agglomeration issues, resulting in defects in coating durability and weather resistance. To address these challenges, this study developed a synergistic modification strategy integrating surface energy modulation with the architectural design of micro/nano-structures. Amino-terminated PDMS undergoes ring-opening addition reactions with epoxy groups in the epoxy resin, while functionalized barium sulfate nanoparticles modified with dual silane coupling agents are incorporated to enhance optical properties. This synergistic approach not only resolved interfacial compatibility but also endowed the PDMS@EP-BaSO₄ coating with outstanding comprehensive properties; the water contact angle increased to 123.5°, demonstrating an easy-to-clean benefit. Visible light reflectance reached 95%, and emissivity rose to 90%. Furthermore, when applied to metal surfaces, the coating exhibited excellent stability against acid–alkali–salt corrosion, extreme temperatures, and ultrasonic agitation. This work provided a novel approach for developing protective coatings that integrated high reflectance, high emissivity, and long-term anti-soiling properties. Full article

To address the critical challenge of drilling fluid invasion in deep coalbed methane (CBM) reservoirs, this study provides novel insight into the micro-scale sealing mechanism and pore structure evolution by leveraging Low-Field Nuclear Magnetic Resonance (LF-NMR) as a quantitative probe. Unlike traditional macroscopic evaluations, we utilized dynamic NMR T₂ spectral analysis to decipher the synergistic behavior of a proposed “Bridging–Filling–Densifying” ternary sealing system, which integrates a nano-plugging agent, micro-fillers, and size-matched skeletal agents. The results demonstrate a significant improvement in sealing efficiency. The optimized hierarchical architecture reduced the NMR signal intensity of the invaded cores by over 99.8% under a differential pressure of 10 MPa, effectively eliminating fluid invasion channels. Crucially, the study reveals that while multi-scale particle size matching is the precondition for sealing, the mechanical rigidity of the skeletal particles is the determinant for maintaining filter cake integrity against high-pressure deformation. These findings elucidate the transition from a “macropore-dominated” structure to a “zero-detectable” sealed state, establishing a robust theoretical framework for designing non-damaging drilling fluids tailored to the complex geomechanics of deep CBM exploration. Full article

Antireflection surfaces play an indispensable role in modern optics, with extensive applications covering optical windows and other precision optical components. The fabrication of anti-reflection surfaces frequently relies on micro/nano-structuring technologies. However, the fabricated micro/nanostructures typically experience performance degradation in transmission enhancement caused by abrasion during operation. To address this problem, we designed and fabricated a double-sided nanocone structure shielded by a protective armor layer. This armor layer efficiently prevents surface mechanical wear and preserves the nanocone structures, leading to almost constant transmittance of the anti-reflection surface even after abrasion. The anti-reflection surface was fabricated by first patterning a square grid armor on one side of fused silica via photolithography, followed by the preparation of an etching mask and nanocone structures using reactive ion etching (RIE). Nanocones were then fabricated on the opposite side of the substrate, finally forming the double-sided nanocone structure. The fabricated armor-protected double-sided nanocone structure exhibited an increase in the average transmittance from 93.43% to 98.31% within the wavelength range of 800–1200 nm. After abrasion testing under 10 MPa pressure, the nanocones under the protective armor showed almost no damage, and the average transmittance remained at approximately 97.85%, demonstrating the outstanding mechanical robustness of the proposed design. Full article

Phase-change materials (PCMs) are capable of storing or releasing a substantial amount of thermal energy within a small volume through the latent heat of fusion during phase transitions of melting and solidification, i.e., from solid to liquid or vice versa, in a near isothermal process. However, commonly used organic PCMs, such as paraffin wax, exhibit very low thermal conductivity, contributing to an adverse increase in overall thermal resistance and, thus, a slow thermal response. This limitation often becomes a bottleneck for the system from a thermal performance standpoint. To mitigate this issue, the present work explores the fabrication of heat sinks incorporating nano-structured graphitic foams, including carbon foam (CF) and expanded graphite (EG), as well as micro-structured metal foams such as open-cell copper foam (OCCF), all impregnated with a paraffin-based PCM with a melting temperature near 37 °C. This study focuses on applying passive thermal management strategies to design efficient heat sinks capable of maintaining the temperatures of battery modules and electronic circuits within an acceptable thermal safety threshold for small satellites and spacecrafts, exemplified by the OPTIMUS and Pumpkin battery modules designed for CubeSats with a nominal cross-sectional area of almost 4″ × 4″. Temperature responses and average overall thermal resistances for fabricated heat sinks are accordingly assessed and compared in a vacuum chamber to simulate space conditions. Furthermore, the impact of operating pressure on the thermal performances of various heat sinks will be investigated by executing the same tests in both atmospheric and vacuum conditions. The findings demonstrate a superior thermal performance of composite heat sinks integrating carbon foam and copper foam into the paraffin PCM compared to the baseline PCM heat sink under both vacuum and atmospheric operating pressure conditions. Full article

This study addresses the challenges posed by weakly cemented strata in mine tunnels, where surrounding rock softens and deforms upon water exposure, which promotes the development of seepage pathways, and exhibits insufficient stability in bolt (cable) support systems. This study conducts laboratory grouting tests using silica sol on typical weakly cemented sandstone from Xinjiang mining areas. The mineral composition and pore structure were characterized using XRD, SEM, and mercury porosimetry. The injectable mixing ratio parameters for silica sol and the catalyst were determined through viscosity-time evolution tests. Grouting was performed using a custom-built constant-pressure grouting apparatus. After curing, unconfined compressive strength (UCS) and porosity-permeability tests were conducted to evaluate the micro-mechanism of grouting effects on the mechanical and permeability properties of weakly cemented sandstone. The results indicate: (1) The sandstone exhibits a high clay mineral content of 39.8%, dominated by illite. Its pores are primarily small-scale (10–100 nm), accounting for 79.31% of the total pore volume. This scale matches that of silica sol nanoparticles (approximately 9–20 nm), facilitating slurry penetration into micro-pores; (2) microscopic analyses reveal that silica sol effectively reconstructs pore structures through permeation filling and surface coating. Compared to KCl-induced gelation (with approximately 8% gel coverage), NaCl-induced gelation forms a more continuous gel film with more complete pore filling, achieving coverage of around 22%. Furthermore, the larger surface area of the gel aggregates indicates a more thorough filling of micro- and nano-pores, effectively enhancing rock mass compactness. (3) Permeability decreased from 6.91 mD to 3.55 mD, a reduction of 48.6%, while porosity decreased from 16.94% to 13.55%, showing a phased reduction during the grouting process; (4) following pressure grouting stabilization, the uniaxial compressive strength of sandstone increased appropriately by approximately 7–14%, while the elastic modulus rose by about 18–28%. The failure mechanism shifted from shear brittleness to a shear-tension composite state, with enhanced post-peak bearing capacity. These findings provide support for optimizing silica sol grouting parameters in weakly cemented strata tunnels and for the synergistic reinforcement of rock mass permeability and strength. Full article

Against the backdrop of increasingly scarce global arable land resources, the remediation and resource utilization of saline–alkali soils have become a critical issue in circular agriculture. This study proposes micro-nano bubble (MNB) irrigation technology as a green, low-carbon strategy for saline–alkali soil remediation, highlighting its multi-level driving mechanism through pot experiments at different aeration frequencies. Results indicated that MNB irrigation significantly enhanced salt leaching and acid-base neutralization by reducing the soil pH (11.75%) and electrical conductivity (53.41%). Meanwhile, soil organic matter, cation exchange capacity, and available nitrogen, phosphorus, and potassium increased to normal soil levels. MNBs also strongly activated native enzymes (urease and alkaline phosphatase), raising the total enzyme activity by 68.54%, which is linked to carbon, nitrogen, and phosphorus metabolism. These results were also validated by microbial analysis, which indicated that MNBs shifted the community structure from one dominated by salt-tolerant taxa (i.e., Pseudomonadota) to a more functionally beneficial composition (i.e., Bacillota). Through these changes, the microbial diversity and network connectivity were enhanced, with Qipengyuania and Psychrophilus identified as critical nodes. This study reveals the multi-level driving mechanism of MNB technology, providing new technical pathways and theoretical support for the remediation, resource recovery, and circular utilization of agricultural waste soils. Full article

Expanded polystyrene (EPS) foam concrete is attractive for lightweight building applications, yet its practical use is often limited by weak EPS–cement interfacial bonding, which promotes interfacial debonding and crack propagation and thereby compromises mechanical performance. Although nano-SiO₂ (NS) has been reported to improve EPS–cement compatibility, the interfacial strengthening mechanism is still not fully clarified across scales, especially the molecular-level interactions that govern the formation of a robust interfacial transition zone (ITZ). Herein, EPS particles were modified with NS and a multi-scale framework (macro tests, micro-characterization, and molecular dynamics (MD) simulations) was employed to establish a mechanistic linkage between interfacial chemistry/structure and macroscopic performance. The results show that an optimal NS dosage of 9% (by cement mass) increases the 28-day compressive strength and flexural strength of EPS concrete by up to 18.3% and 11.2%, respectively, compared with the unmodified system. SEM, XRD, and FTIR collectively indicate a denser interfacial microstructure, increased hydration-product accumulation near the EPS surface, refined interfacial porosity, and the occurrence of condensation-related reactions involving NS. MD simulations further reveal that NS facilitates the formation of molecular bridges between EPS and C–S–H through hydrogen bonding and ionic interactions, which enhances interfacial adhesion and contributes to improved ITZ thermal stability. This study provides a cross-scale mechanistic understanding for designing high-performance EPS foam concrete via targeted interfacial engineering. MD simulations further suggest that NS enhances interfacial bonding by increasing the occurrence of hydrogen-bond networks and ionic associations at the EPS/C–S–H interface, as evidenced by the intensified interaction-related distributions and peaks in the simulation outputs. Full article