The impacts of microstructures and airborne-particle abrasion on the additively manufactured zirconia bond strength with and without thermocycling.

Advanced biomechanics and stability of the resin-dentin complex via modular A- and B-type proanthocyanidins.

1,10-Phenanthroline enhances dentin bond durability via dual-site binding to collagen and matrix Metalloproteinase-8.

Dental caries remains a major challenge in clinical dentistry, with successful resin restoration relying on the formation of a durable dentin-resin interface. In minimally invasive dentistry (MID), caries-affected dentin (CAD) is routinely preserved and often becomes the primary bonding substrate. However, bonding to CAD is suboptimal, and current strategies to improve this interface are limited. Here, we present a novel bonding strategy based on a dual-reactive functional monomer, ITCM, in combination with pretreatment application techniques. A simple 5-s ITCM pretreatment significantly enhanced both immediate and aged bond strength to CAD. Acting as a "molecular bridge", ITCM bridges hydrophilic CAD layer with hydrophobic adhesive layer, facilitating the formation of a chemical interlocking structure, increasing CAD surface energy, and promoting deep adhesive infiltration. In addition, ITCM improves collagen enzymatic resistance and functions as a non-zinc-binding inhibitor of MMPs. Biocompatibility assessments demonstrated acceptable in vitro and in vivo safety, supporting its clinical potential. This study addresses a critical challenge in dentistry by introducing a chemical bonding strategy tailored to CAD. The ITCM pretreatment strategy provides a foundation for next-generation adhesives aimed at reinforcing the CAD-resin interface, extending restoration longevity, and preventing secondary caries.

Enhancing interlayer bond strength of 3D-printed concrete through microstructural densification by means of incorporating sugarcane bagasse ash

Programmable magnetic-induced functional gradient hydrogel for NIR-driven underwater soft robots.

Laser-textured polymer-metal bonding: A combined experimental and computational approach to enhanced mechanical bond strength

Shear bond strength is a critical indicator of the bonding efficiency between pavement layers, playing a pivotal role in applications such as the stress-absorbing membrane interlayer (SAMI), which are designed to improve crack resistance and extend the life span of road pavements. This study explores the influence of two additives, low-density polyethylene (LDPE) and cement kiln dust (CKD), on the shear strength and stiffness of SAMI blends. Various proportions of LDPE (2%, 4%, and 6%) and CKD (4%, 8%, and 12%) were incorporated into SAMI formulations, and their effects were assessed using a specialized shear bond strength test. The findings revealed a progressive increase in peak shear strength, maximum shear strain, and stiffness with higher additive concentrations. SAMI blends containing LDPE exhibited the highest shear strain, along with superior ductility and flexibility when compared with the control blend, where the maximum shear strain occurred in the blend with 6% LDPE, reaching 0.042, compared with 0.037 for the control blend. Notably, the blends containing both LDPE and CKD demonstrated the best performance, achieving the highest peak shear strength of 0.58 MPa and stiffness of 0.2 MPa/mm, outperforming the control blend (0.34 MPa and 0.096 MPa/mm). Furthermore, these blends showed enhanced energy-absorption capacity, as indicated by the area under the shear strength-displacement curve before and after reaching peak shear strength. The blend containing 4% LDPE and 8% CKD achieved a total area of 9.29 MPa.mm under the curve, compared with the 6.3 MPa.mm of the control blend. In conclusion, the incorporation of LDPE and CKD into SAMI blends resulted in significant improvements in mechanical properties, offering a possible lower risk of reflective cracking and the potential for longer pavement life.

A Bayesian probabilistic model of bond strength in RC Beams externally confined with Fiber-Reinforced Polymer (FRP)

This study investigates the effects of adding zeolite in concrete mix on the mechanical and durability properties of concrete, aiming to enhance performance and sustainability. Zeolite, a microporous aluminosilicate mineral, is renowned for its molecular sieve properties, which enable it to improve strength of concrete, reduce permeability, and offer environmental benefits by decreasing the cement content required in concrete mixtures. By introducing zeolite as a partial substitute, this research aims to identify the optimal replacement percentage that maximizes structural integrity while maintaining or improving durability. The experimental methodology involves preparing a series of concrete mixes with varying zeolite contents to systematically assess changes in key mechanical properties, such as compressive, flexural, tensile, and bond strength. Durability characteristics are also evaluated, including resistance to acid and base exposure, chloride-induced corrosion which measures the material’s susceptibility to water absorption. The approach combines meticulous material collection, precise mix proportioning, and rigorous mechanical and durability testing to capture the effects of zeolite on concrete performance comprehensively. These insights are expected to contribute to sustainable construction practices by reducing cement dependency and, consequently, the carbon footprint of concrete production. If effective, zeolite could be a promising addition to the construction industry, potentially increasing lifespan of concrete, resilience to environmental stressors, and suitability for eco-friendly infrastructure. Through this research, potential of zeolite as a sustainable additive is highlighted, offering an innovative approach to develop concrete with enhanced structural integrity and extended service life, supporting green building initiatives, and contributing to more durable and environmentally conscious infrastructure solutions.

Methane's efficient catalytic removal is vital for sustainable development. Bimetallic catalysts, though promising for methane activation, pose a design challenge due to their complex compositional space. This work introduces an integrated framework that combines high-throughput density functional theory (DFT) and interpretable machine learning to accelerate the rational design of catalysts. Computational screening of face-centered-cubic (FCC) bimetallic catalyst surfaces identifies the bond cleavage energies of the first and the second C─H bonds and methyl adsorption energy as a key descriptor governing successive C─H activation and the shift in the rate-determining step (RDS). Through the synergistic interaction of these descriptors, machine learning models can be constructed more effectively, leading to the discovery of a bimetallic catalyst for consecutive C─H bond cleavages that outperforms conventional natural gas engine aftertreatment systems. Based on the computationally derived DFT dataset, four machine learning models were trained using a particle swarm optimisation (PSO) algorithm, from which the optimal model capable of accurately predicting C─H bond energies was selected. This model also further revealed the dominant electronic structural features of the predictive model through SHapley additive interpretability (SHAP) analysis. This work establishes an interpretable, data-driven methodology for designing high-efficiency multicomponent catalysts.

Grain boundaries (GBs) can tailor the macroscopic properties of polycrystalline materials via their intrinsic structural and electronic states. However, as independent heterointerfaces, their role in stabilizing grain phases remains largely unexplored, especially at the atomic scale. Here we report that chemically ordered heterogeneous GBs in ZrO2 thin films act as active stabilizers of a metastable polar phase. The atomically sharp and ordered La(Sr)-Mn-O configurations at GBs are identified at the atomic scale. The resultant charge ordering and bond covalency of the GBs are validated by four-dimensional scanning transmission electron microscopy. This structural motif induces eg/t2g orbital ordering of Mn ions at GBs, modulating Zr-O bond strength to stabilize the polar phase. This work establishes a GB-centric paradigm for engineering nanoscale phase diagrams, offering a promising strategy for designing metastable functional materials via GB chemistry.

This work establishes a materials design paradigm that achieves simultaneous enhanced stability and performance for photon-based propulsion. We introduce an atomic-level bimetallic platform to overcome the inherent trade-off between high thrust efficiency and environmental stability, particularly against hydrolysis. This is achieved through bimetallic FeCu-MOFs synthesized via a one-step laser synthesis, where Fe3+ and Cu2+ co-crystallize with tricarboxylate ligands to form an isomorphous HKUST-1 derivative. This approach exploitshard-soft acid-base principlesto achieve several fundamental advances: enhanced bond strength, hydrolytic and thermal stabilitythrough the formation of robust Fe-O bonds, increasing water resistance by 20 times while preserving crystalline integrity; synergistic, delocalized energy dissipationvia d-orbital charge transfer (Fe3+→Cu2+), boosting uniform photothermal conversion to 91%; and inherent stoichiometric tunability, where the Fe:Cu ratio serves as a precise performance lever, providing a design strategy to optimize stability and performance. The optimized FeCu-MOF-M variant achieves record propulsion metrics-impulse coupling coefficient (191.80 µN/W), specific impulse (631.19 s), thrust density (61.86 µN/µg), and ablation efficiency (59.32%) -surpassing monometallic HKUST-1 by 15.7% and physical mixtures by 125%. By unifying hydrolysis resistance, efficient photothermal conversion, and atomic-level tunability, this stoichiometry-driven photothermal synergy bimetallic frameworks provides a solid foundation for next-generation energetic materials in demanding environments.

This study evaluated the incorporation of epigallocatechin-3-gallate (EGCG)-loaded poly(lactide-co-glycolide) (PLGA) microparticles into a two-step etch-and-rinse adhesive and their effects on physicochemical properties and EGCG release. EGCG was added to Single Bond 2 either directly (0.01% and 0.1% w/w) or encapsulated in PLGA 50:50 or 75:25 microparticles (0.5%-2% w/w). Cumulative release was measured by UV-Vis spectrophotometry. Degree of conversion (DC) was analyzed by Fourier transform infrared spectroscopy; flexural strength and elastic modulus (E) were tested in three-point bending; and water sorption (WS) and solubility (SL) were evaluated following ISO standards (n=10). Microtensile bond strength (TBS) was tested after 24h, 6, and 12 months. Data were analyzed by anova with significance set at p<0.05. PLGA 50:50/EGCG at 1% showed the highest release, reaching 77.30µg. No significant differences were found in DC, E, WS, and SL among the groups. Bond strengths remained stable in all experimental groups after 6 and 12 months, except for the control. Incorporating 1% EGCG-loaded PLGA 50:50 microparticles into Single Bond 2 may represent a promising strategy for controlled release without compromising physicochemical or mechanical properties.

The rational design of stimuli-responsive organic room-temperature phosphorescence (RTP) materials is often hindered by an incomplete understanding of the intricate interplay between molecular structure, crystal packing, and excited-state dynamics, particularly in polymorphic systems. Clarifying how subtle structural variations govern photophysical properties is crucial for advancing tunable luminescent materials. Herein, we systematically investigate the dual-emission mechanism and pressure-responsive behavior of a polymorphic RTP material, BrTA-F, in its two crystalline phases (Cry-A and Cry-B), using density functional theory (DFT) and time-dependent density functional theory (TDDFT) combined with quantum mechanics and molecular mechanics methods (QM/MM) and thermal vibration correlation function (TVCF) methods. The results reveal that the distinct spatial distribution of fluorine (F) atoms modulates intermolecular interactions and molecular planarity, leading to different hydrogen bond strengths and excited-state characteristics between the two polymorphs. The dual-RTP emission in Cry-B is attributed to competitive radiative decay from the monomeric first (T1) and second (T2) triplet excited state, which is facilitated by enhanced spin orbit coupling (SOC) resulting from variations in n-π*/ππ* transition proportions. Furthermore, Cry-A demonstrates high sensitivity to hydrostatic pressure, which tunes the emission wavelength and decay rates by compressing the lattice and altering intermolecular force balances. This work provides fundamental insights into the structure-property relationships in polymorphic RTP systems and offers guidance for designing stimuli-responsive luminescent materials.

To evaluate the effects of formulations containing potassium nitrate, silicate, and calcium phosphate, subjected to an acid challenge, on debris precipitation, quantification of exposed dentinal tubules, bond strength, failure mode, and tag formation. One hundred and twenty bovine incisors were randomly allocated into four groups: Desensibilize NanoP, Desensibilize KF 2%, Regenerate NR-5, and a control group. Specimens were immersed daily for 5min in orange juice (pH 3.80 ± 0.04) and then rinsed with distilled water. Forty teeth were analyzed by scanning electron microscopy to assess debris precipitation and tubular occlusion. Another forty were subjected to micro-shear bond strength testing, and the remaining forty were analyzed under optical microscopy for tag formation. Data were analyzed using the Kruskal-Wallis/Dunn test (debris precipitation) and ANOVA/Tukey test (open tubules, bond strength, and tag formation), with a significance level of α = 0.05. The Regenerate group showed significantly higher debris precipitation, fewer open dentinal tubules, greater bond strength, and a higher incidence of cohesive failures. Tag formation was similar across all groups. The Regenerate protocol demonstrated superior performance in debris precipitation, tubule occlusion, bond strength, and tag formation, particularly when used in combination with a universal adhesive.

The effect of a feldspathic porcelain coating applied before or after zirconia sintering on the shear bond strength between a resin luting agent and zirconia was evaluated. Pre-sintered and fully sintered zirconia specimens were coated with feldspathic porcelain and divided into three surface treatment groups: no treatment, airborne-particle abrasion, and hydrofluoric acid etching. The specimens were bonded using a dual-polymerizing resin luting agent and subjected to 0 or 5,000 thermocycles. The shear bond strength was measured. The fracture modes were analyzed microscopically. The surface morphology and composition were examined by scanning electron microscopy (SEM) and X-ray diffraction. Before thermocycling, both airborne-particle abrasion and hydrofluoric acid etching significantly increased the bond strength compared with no treatment. After thermocycling, airborne-particle abrasion maintained the highest bond durability, while hydrofluoric acid etching showed a marked decrease. SEM revealed that airborne-particle abrasion produced a rough surface favorable for micromechanical retention, whereas hydrofluoric acid etching resulted in smoother morphology. Airborne-particle abrasion effectively enhanced and preserved the bond strength between the resin luting agent and feldspathic porcelain-coated zirconia, regardless of the coating sequence. Hydrofluoric acid etching was ineffective after thermocycling, likely due to surface precipitation that occurred during firing.

Surface treatment of zirconia before cementation can be performed using different methods, e.g. airborne particle abrasion (APA) or various etching protocols. This study evaluated the effect of storage time between surface treatment and cementation on the surface free energy (SFE) of zirconia, the bond strength of composite cement, and failure mode. Rod-shaped zirconia specimens were fabricated and assigned to two surface treatment groups: APA (n = 80) and hot etching with potassium hydrogen difluoride (KHF2, n = 80). Each group was divided into four storage time subgroups: immediate, 24 h, 1 week, and 1 month. After storage, specimens were either analyzed for SFE (n = 10) or cemented for shear bond strength (SBS) testing and failure mode evaluation (n = 10). Two-way analysis of variance (ANOVA) showed a significant effect of both surface treatment and storage time on SFE (P 0.05), with KHF2-etched zirconia exhibiting the highest values across all time points. In both groups, SFE gradually decreased with increased storage. Surface treatment did not significantly affect SBS (P > 0.05). Storage time significantly influenced SBS (P 0.05), specifically for KHF2-etched zirconia; post-hoc comparisons showed higher SBS after 1 week than at immediate testing (P 0.05). Although adhesive failures to cement increased with longer storage time for KHF2-etched specimens, this trend was not significant (P > 0.05). For APA specimens, the highest incidence of adhesive failures (n = 9) to cement occurred after 24 h of storage. Given the significant decrease in SFE with prolonged storage and adhesive failures to zirconia tended to increase over time, minimizing the interval between surface treatment and cementation is recommended.

This systematic review evaluated the influence of resin-based, eugenol-based and bioceramic endodontic sealers on the bond strength of glass fibre posts cemented with resin cements. Searches were conducted in PubMed, Scopus, Web of Science, Cochrane Library, Google Scholar and Embase, including invitro studies using human or bovine teeth restored with fibre posts. Risk of bias was assessed using the QUIN Tool. Thirty three studies met the eligibility criteria. Most evidence indicates that resin-based sealers promote higher bond strength values than eugenol-based sealers, whereas findings for bioceramic sealers were inconsistent. Only a minority of studies showed a low risk of bias, while most presented moderate methodological limitations. Substantial heterogeneity was also observed, including differences in irrigation protocols, sealer types, adhesive strategies and post-cementation intervals. Within the limitations of the available evidence, resin-based sealers appear to be the most favourable choice for clinical fibre post cementation. PROSPERO Registration Number: CRD42023467018.

The hybrid decavanadate with macrocycle cyclen (1,4,7,10-tetraazacyclododecane) complexes with the formula [Ni(cyclen)(H2O)2]2[H2V10O28]·2H2O (1) was prepared as an ionic pair, while [{Cu(cyclen)}2(H2V10O28)]·9H2O (2) and [{Zn(cyclen)}3(V10O28)]·4H2O (3) were obtained as discrete molecular entities. The structures of 2 and 3 revealed a new coordination mode for the decavanadate anion, involving a triply bridging oxygen (-μ3-OB) and {TM(cyclen)}2+, where TM = Cu(II) or Zn(II). Electrostatic Surface Potential analysis showed pronounced π-holes in the {Cu(cyclen)}2+ and {Zn(cyclen)}2+ fragments, whereas {Ni(cyclen)}2+ lacks this feature due to stronger metal-cyclen σ-bonding. The Independent Gradient Model based on Hirshfeld partition analysis of {TM(cyclen)}/decavanadate interfaces demonstrated that intramolecular noncovalent interactions play a key role in structural stability. The low Intrinsic Bond Strength Index for the Cu-OB bond (0.087) suggests a weak, semicoordinative interaction with approximately half the strength of the Zn-OB coordination bond (0.169). The adsorption of methylene blue was characterized as a surface phenomenon. The bleaching efficiency, 2 > 1 > 3, was determined by the distribution of their asymmetric surface charge and particle size. These hybrid compounds provide a valuable model for understanding and advancing decavanadate coordination chemistry and for the application of polyoxometalates to remove prevalent contaminants from wastewater.