Enhanced supercapacitance performance via surface roughness optimization using acidic etching

Preparation of carboxymethyl chitosan/polyvinyl alcohol double-layer film loaded with tannic acid- zeolitic imidazolate framework-8@quercetin particles for lotus root preservation.

Study on the effects of dopamine-modified electroplating bath on the performance of copper plating on carbon fiber surfaces

Electron beam absorbed current (EBAC) microscopy can provide spatially resolved electrical information that conventional probe methods and local scanning probes often miss in nanoparticulate thin films. Here we present the development of a practical scanning electron microscopy (SEM)-based methodology to qualitatively assess conductivity uniformity and electrical continuity in thin films spanning two electrodes using TiO2 films as a model system. The approach combines a purpose-built insulating holder, readily made without clean-room and advanced lithography access, with embedded electrodes and a measurement configuration to visualize current pathways and identify electrically disconnected regions that may not be apparent from morphology alone. Line scans and 2D maps enable rapid screening of film quality, highlighting cracks, and poor particle connectivity. The workflow is designed for reproducibility and can be adapted to other semiconducting or weakly conducting thin films where microscale continuity is critical to device performance. Fabricate a biasable dual-electrode SEM holder by embedding bent copper plates in an insulating resin body and machining a defined deposition channel (drilled to expose copper + resin in one plane), enabling repeatable electrode gaps and robust external connections for EBAC measurements. Prepare thin films that reliably bridge the electrode gap by using a diluted, well-dispersed nanoparticle suspension (e.g., TiO2 in IPA) and controlled drop-casting into the channel; confirm continuous coverage using standard SEM imaging before electrical mapping. Map conductivity uniformity in situ using EBAC (line scans and 2D maps under applied voltage) to rapidly locate conductive pathways and diagnose electrically disconnected regions that may appear morphologically continuous, providing a reproducible screening workflow adaptable to other weakly conducting thin films.

Resin-dentin bonding technology is the primary method for tooth restoration in clinical practice. However, the formation of a defect zone at the bonding interface due to inadequate moisture control at the interface remains a major challenge. Inspired by mussel wet-adhesion mechanisms, this study functionalized phosphoric acid etchants with catechol-lysine-methacrylate (CLM), a polymerizable small-molecule monomer. During dentin demineralization, catechol binding to demineralized dentin was confirmed using an incubation-rinsing technique, while lysine's role in facilitating rapid water release at the bonding interface was validated by freeze-drying mass loss, surface charge distribution, and thermogravimetric analysis. Confocal laser scanning microscopy revealed increased resin tag lengths in the CLM-treated groups, indicating enhanced resin infiltration. Ultimate tensile strength, dry mass loss, sodium dodecyl sulfate-polyacrylamide gel electrophoresis, and in situ zymography demonstrated catechol-enabled collagen stabilization via Schiff base/ester bonds and endogenous enzyme inhibition. Micro-tensile testing revealed that the 4- to 5-mg/mL CLM groups maintained bond strength after 10,000 thermal cycles. Thus, CLM-functionalized etchants may enhance bonding durability in vitro by improving moisture control and collagen stability.

Universal adhesives (UAs), introduced in 2011, are well established in restorative dentistry but remain relatively unexplored in orthodontics, where their capacity to bond to enamel and multiple restorative materials could simplify bonding protocols and reduce the need for primers. This systematic review evaluated the bond strength of UA for orthodontic applications-including bracket bonding, fixed retainers, and bonding to restorative surfaces-compared with conventional adhesives. Searches were conducted in PubMed, Embase, Scopus, Web of Science, and the Cochrane Library, supplemented by Google Scholar and reference lists. The protocol was registered in PROSPERO (ID: CRD420250654277). The search covered 2011 to 1 December 2024. Eligible studies were in vitro, in vivo, or clinical studies in English assessing UA for orthodontic bonding. Exclusion criteria were case reports, reviews, abstracts, theses, and non-orthodontic applications. Risk of bias was assessed with QUIN tool (in vitro) and RoB-2 (clinical). Of 401 records, 323 remained after removing duplicates; 248 were excluded at title/abstract and 38 at full text, leaving 37 studies (36 in vitro; 1 with an in vitro and clinical component). Seven orthodontic applications were investigated. UA generally provided sufficient bond strength, except on some metal restorations. On enamel, phosphoric-acid etching for 15s improved adhesion. On ceramics, hydrofluoric acid etching (HF) or sandblasting enhanced performance. For polymethyl-methacrylate (PMMA) and composite restorations, bur roughening or sandblasting improved results. UAs may simplify orthodontic bonding across enamel and restorative surfaces without separate primers, but more clinical studies are needed.

Influence of laminarin on adhesive bond stability, MMP activity, and collagen cross-linking in caries-affected dentin.

The severe dendrite growth and inherent surface passivation layer of Zn anodes greatly undermine the reversibility and practicality of aqueous zinc-ion batteries (ZIBs). Herein, an optimized chemical polishing strategy to texture Zn metals is developed via the incorporation of the acid etching solution and alkyl polyglucoside (APG) surfactant. The APG-assisted acid-etched Zn metals (AAE-Zn) possess a surface free of passivation layer and a high (002) texture. Mechanistic studies reveal that APG significantly improves the wettability between the acid etching solution and Zn metals, avoiding the incomplete etching caused by the adhesion of generated bubbles to the Zn metal surface. Additionally, APG featuring preferential adsorption on the (100) and (101) crystal planes can increase the etching efficacy of the above two crystal planes to render the high proportion (002) texture remaining. The cooperation of no passivation layer surface and (002) texture not only suppresses dendrite growth and related side reactions but also ensures uniformly distributed electric field and Zn2+ ion flux. Consequently, AAE-Zn electrodes exhibit long-term lifespan over 4000 h at 1 mA cm-2 and 110 h at 85% depth of discharge in the symmetric cells and maintains 80% of the initial capacity after 1500 cycles at 10 A g-1 for coin-type full cells. This chemical polishing approach offers a compelling strategy to propel the large-scale commercialization of aqueous ZIBs toward realization.

This paper describes a study on the formation and process parameters of friction stir welding joints on 6 mm thick copper plates. Numerous experiments were conducted at lower rotational speeds and moderate welding traverse speeds to obtain optimal process parameters for high-quality friction stir welding joints with good surface formation and no internal defects. Simultaneously, considering the thickness tolerance fluctuations in the large-scale engineering application of Copper FSW, tests were conducted with pin lengths and shoulder plunge depths less than the plate thickness. Additionally, a unique modular stirring tool was designed by ourselves to reduce costs in large-scale engineering applications. The experimental results demonstrate that under the parameters of a rotational speed of 275 r min−1 and a traverse speed of 120 mm min−1, welding joints with both surface and internal integrity can be achieved, with the joint strength level exceeding 80% of the base material. The mechanical weak point of the joint is located in the TMAZ region just below the pin as revealed by SEM testing, which shows both plastic and brittle fractures. EDS results indicate no inclusions or second-phase precipitates at the surface and port locations.

There is limited evidence regarding the effect of demineralization around orthodontic brackets on shear bond strength (SBS). The aim of this in vitro fatigue study was to evaluate the effect of demineralization developing around orthodontic brackets bonded with different adhesive agents on fatigue-based SBS under laboratory conditions. A total of 60 extracted human maxillary premolars bonded with Gemini metal brackets were randomly allocated into three groups (n = 20). Bracket bonding was performed using Transbond™ XT (acid etching + primer + adhesive) in Group 1, GC Ortho Connect® (acid etching + one-step adhesive) in Group 2, and Transbond™ Plus (self-etch primer + adhesive) in Group 3. The mean demineralization values of the specimens were measured using a DIAGNOdent pen before demineralization (T0) and after 28 days of exposure to an artificial cariogenic environment (T1). Fatigue-based SBS was evaluated under cyclic loading (10N, 0.5Hz) at a crosshead speed of 300mm/min using a low-cycle fatigue testing machine and expressed as the number of shear strokes to failure. The level of statistical significance was set at p < 0.05. There were no significant differences in demineralization values among the groups at either T0 or T1 (p > 0.05). However, all groups showed a significant increase in demineralization at T1 compared with T0 (p < 0.05). Group 2 (GC Ortho Connect®) had a significantly higher number of shear strokes to failure than Groups 1 (Transbond™ XT) and 3 (Transbond™ Plus) (p < 0.05). No significant difference was observed between Groups 1 and 3 (p > 0.05). A significant negative correlation was observed between demineralization and shear strokes to failure across all groups (p < 0.05). Hard tissue (enamel and dentin) damage occurred in nine specimens in Groups 1 and 3, and in seven specimens in Group 2. Increased demineralization may negatively affect fatigue-based SBS and increase the risk of hard tissue damage. Under demineralized conditions, GC Ortho Connect® may demonstrate more favorable fatigue-based bond performance compared with the other adhesive agents evaluated; however, further studies under clinically representative conditions are needed.

This in vitro study aimed to evaluate and compare the microleakage of Class II composite restorations bonded with universal adhesives containing different functional monomers, with particular emphasis on a chemically cured universal adhesive applied using different etching strategies. Standardized Class II cavities were prepared in 120 extracted human molars and randomly allocated into 12 groups (n = 10) according to the adhesive system and etching strategy. The adhesives evaluated included a three-step etch-and-rinse system, a two-step self-etch system, and three universal adhesives applied in total-etch, selective-etch, and self-etch modes, including a chemically cured universal adhesive. All cavities were restored with a nanohybrid resin composite and subjected to 5000 thermocycles between 5°C and 55°C. Microleakage at occlusal and gingival margins was assessed using 0.5% basic fuchsin dye penetration under stereomicroscopy. Data were analyzed using non-parametric statistical tests (α = 0.05). Significant differences in microleakage were observed among the groups (p < 0.001). The three-step etch-and-rinse adhesive demonstrated the lowest microleakage values at both occlusal and gingival margins. Universal adhesives applied in self-etch mode exhibited significantly higher microleakage, particularly at the gingival margin. The chemically cured universal adhesive showed comparable marginal sealing only when combined with phosphoric acid etching. Within the limitations of this in vitro study, multi-step adhesive systems and universal adhesives used with total-etch or selective-etch strategies provided superior marginal sealing compared with single-step self-etch applications. These findings highlight the clinical importance of etching strategy selection in Class II composite restorations, particularly at gingival margins where light attenuation may compromise polymerization in deep proximal boxes.

This in vitro study aimed to evaluate and compare the effects of SDF- and SDF + KI-based pretreatment protocols, with or without NaOCl surface preparation, on microleakage, discoloration, and fissure sealant penetration depth in permanent teeth. Sixty extracted mandibular permanent molars with non-cavitated initial enamel lesions (ICDAS score 1) were randomly allocated into six groups (n = 10 per group). According to the experimental design, SDF, SDF + KI, NaOCl surface preparation, and orthophosphoric acid etching protocols were applied before fissure sealant placement. Color measurements were performed using a spectrophotometer according to the CIE Lab* system at baseline (T0) and after all procedures (T1). Microleakage and penetration depth were evaluated using confocal laser scanning microscopy (CLSM). Statistical analyses were performed using the Kruskal-Wallis test and Bonferroni-adjusted pairwise comparisons (α = 0.05). Significant differences were observed among the groups for color change (ΔE) and lightness change (ΔL) (p < 0.001). SDF-treated groups showed significantly higher color change and greater lightness reduction compared with the control group. The mean ΔE values were 6.38 ± 5.42 in the control group, 15.78 ± 2.73 in the SDF group, and 12.60 ± 1.68 in the SDF + KI group. Most ΔE values exceeded the perceptibility (PT = 1.2) and acceptability (AT = 2.7) thresholds. NaOCl application following SDF resulted in significantly higher ΔL values compared with SDF alone. No statistically significant differences were observed among groups for microleakage or penetration depth (p > 0.05). SDF and SDF + KI pretreatments did not result in statistically significant differences in microleakage or penetration depth under the present experimental conditions, although SDF was associated with clinically relevant discoloration. KI showed only a limited effect in reducing this discoloration. NaOCl application was associated with less unfavorable lightness change in some comparisons; however, this finding should be interpreted cautiously.

Transition metal phosphosulfides (TMPs) are compelling anode candidates for sodium-ion batteries thanks to their distinctive layered structure and outstanding electrochemical properties, yet facing significant intrinsic challenges including poor electronic conductivity and severe structural degradation. To address these issues, we demonstrate the construction of yolk-double-shell ZnPS3/N-doped carbon@carbon (ZnPS3/NC@C) polyhedra through a Kirkendall-effect-mediated tannic acid (TA) etching strategy using a resorcinol-formaldehyde (RF) coated ZIF-8 precursor. This rationally designed architecture confers several synergistic advantages: (i) the N-doped carbon matrix derived from ZIF-8/TA-Zn and the carbon shell from RF form a continuous conductive network, facilitating rapid charge transfer; (ii) the yolk-double-shell framework with ample internal void space effectively accommodates the volume variations, preserving structural integrity; and (iii) the outer carbon shell serves as a physical barrier against polysulfide dissolution, enhancing reaction reversibility. Benefiting from this multi-synergistic engineering, the novel ZnPS3/NC@C anode exhibits impressive sodium storage performance, delivering a high charge/discharge capacity of 925.7/1128.9 mAh g-1 at 0.1 A g-1, along with a remarkable long-term cyclability with 96.9% capacity retention over 2000 cycles at 2.0 A g-1. This work establishes a generalizable design paradigm integrating morphological manipulation with multi-component compositing for developing advanced electrode materials.

Defect engineering provides new opportunities to overcome the intrinsic limitations of metal-organic frameworks (MOFs) in photocatalysis. Herein, a cluster-defect engineering (CDE) strategy is employed to modify the pristine UiO-66 framework, wherein Zn incorporation followed by selective acid etching yields defect-rich A/(Zn,Zr)UiO-66 catalysts featuring hierarchical porous architectures and abundant Lewis (L) acid sites. Optical and photoelectrochemical analyses confirm that CDE broadens visible-light harvesting, narrows the bandgap, and prolongs carrier lifetimes. The synergistic interplay between L acid sites and photocatalysis over A/(Zn,Zr)UiO-66 results in an excellent photocatalytic performance in biodiesel production via oleic acid (OA) esterification with methanol (CH3OH) under mild reaction conditions, outperforming pristine UiO-66. Notably, the optimized A/(Zn,Zr)UiO-66-0.2 achieves a remarkable 99.3% biodiesel yield under mild conditions, alongside superior stability and reusability. Further, in situ spectroscopic investigations and density functional theory (DFT) calculations disclose that CDE lowers the coupling barrier of OA and CH3O• radicals by strengthening OA adsorption and activation as well as facilitating charge stabilization at unsaturated Zr sites. This work highlights CDE as an ingenious strategy for tailoring the electronic configuration and interfacial chemistry of MOFs, offering a versatile platform for visible-light-driven biomass upgrading and sustainable fuel production.

To evaluate the shear bond strength (SBS) of newly developed composite resin materials intended for dental splinting to enamel and to determine whether phosphoric acid etching alone provides reliable adhesion. Four experimental materials (G-Fix, Light Fix, Ortho Connect, and Ortho Connect Flow) were compared with conventional composite resins applied to phosphoric acid-etched enamel, with or without a universal adhesive. After thermocycling, SBS was measured and failure modes were assessed. Wettability was evaluated by contact angle measurement, and the resin-enamel interfacial microstructure was examined using atomic force microscopy. Across all materials, application of a universal adhesive did not increase SBS. SBS was significantly reduced for Light Fix and Ortho Connect Flow when the adhesive was used. When applied directly to etched enamel, all experimental materials achieved clinically acceptable SBS. Interfacial analyses supported that adhesion was predominantly mediated by functional monomer-driven chemical interactions rather than enhanced micromechanical retention. For the tested splinting composites, phosphoric acid etching followed by direct composite application provided reliable enamel adhesion, and the additional use of a universal adhesive was unnecessary and may be detrimental for selected materials. This simplified protocol may be suitable for clinical splinting procedures.

ABSTRACT This study prepared PI/PTFE (polyimide/polyfluoroethylene) bilayer composite films. Firstly, the inert surface of the PI film was modified using chemical wet acid etching. Subsequently, PTFE latex and FEP latex were blended and applied onto the modified PI film through a coating–drying–sintering process to form the bilayer composite film. The film formation and modification mechanism were investigated, and comprehensive analysis was conducted on the surface morphology, thermal properties, crystallinity properties, and mechanical properties of the composite film samples. Contact angle measurements and SEM results demonstrated that acid‐etched wet treatment effectively enhanced the surface roughness of the PI film, improving latex film formation. FT‐IR confirmed the chemical structural stability of the blended PTFE/FEP (fluorinated ethylene propylene) alloy coating after thermal treatment. Cross‐sectional SEM and mechanical testing revealed reliable adhesion between the blended coating and the modified PI substrate. DSC and GI‐XRD studies elucidated FEP's influence on coating crystallinity. Subsequent in situ POM analysis revealed that FEP, acting as a filler, improved PTFE flowability and reduced stress relaxation, transforming the coating surface from convex to concave. This topographical change was confirmed by SEM characterization and further validated by peel test results.

Synergistic optimization effect on enhanced toluene oxidation over YMn2O5 mullite catalysts via A-site Ce doping and acid etching

In this work, a 2D axisymmetric FEM model was produced to simulate OpenStar Technologies' Junior Core Magnet. The model was created in COMSOL Multiphysics, with electromagnetic and thermal coupling. This model was used to simulate the Core Magnet under full-field conditions, and was verified against the specifications of the Core Magnet. Producing the model involved creating lookup tables of homogenised electrical and thermal properties for each of the 14 solder impregnated coils, applying coordinate transformations to these lookup tables, and creating 2D axisymmetric equivalent geometry of the complex copper interface buses and plates between the coils. This paper provides insight into understanding the behaviour of NI coils and how they influence quench dynamics, current redistribution, and thermal response. The modelling approach demonstrates that computationally efficient simulations can be achieved through homogenisation and geometry simplification, offering a valuable tool for the design, optimisation, and safety assessment of large-scale superconducting magnets.

Introduction: Chlorhexidine (CHX) has been most commonly used as an antimicrobial component as well as for disinfection before the placement of restorations. CHX has demonstrated successful inhibition of dentin Matrix Metalloproteinase (MMP) collagenolytic activity when used in concentrations of 0.2% and 2%, however this may influence the bond strength of composite resin to Biodentine when applied before adhesive procedures. The present study endeavours to evaluate a bonding strategy that would best suit the preconditioning with CHX. Aim: To evaluate the effect of two different concentration of CHX on Shear Bond Strength (SBS) between resin composite and Biodentine, using self-etch and etch-rinse bonding strategies. Materials and Methods: The present in-vitro study was carried out in the Department of Conservative Dentistry and Endodontics in Mahatma Gandhi Mission Dental College and Hospital, Navi Mumbai, Maharashtra, India, from January 2022 to May 2022 on 108 acrylic blocks. A central cavity was prepared in the acrylic block and randomly divided into six main groups. Group 1 (control) Biodentine placement; selfetch adhesive application followed by resin composite. Group 2 (control) Biodentine placement; etch and rinse adhesive application followed by resin composite. Since two different bonding strategies, self- etch and etch-and-rinse were used, two control groups were included. Each of these bonding methods has different application protocols and bonding mechanisms, which could independently affect the SBS between resin composite and Biodentine, therefore two control groups were included. Including both controls allows for a fair and unbiased comparison with the experimental groups where CHX (at 0.2% or 2%) was used. This ensures that any observed differences in bond strength can be accurately attributed to the effect of CHX, rather than differences between the bonding strategies themselves. Group 3 Biodentine placement; application of 0.2% CHX prior to application of self-etch adhesive followed by resin composite placement. Group 4 Biodentine placement; application of 2% CHX prior to application of self-etch adhesive followed by resin composite placement. Group 5 Biodentine placement; for etch and rinse adhesive system application 0.2% CHX after acid etching prior to application of adhesive followed by resin composite placement. Group 6 Biodentine placement; for etch and rinse adhesive system application 2% CHX after acid etching prior to application of adhesive followed by resin composite placement. Thereafter the samples were subjected to the shear bond testing in a universal testing machine. The obtained data was tabulated and statistically analysed for normality using Shapiro-wilk test. Further statistical analysis was done using One-way Analysis of Variance and Two-way ANOVA followed by Tukey–Kramer Test for pair-wise comparisons. Post-hoc test was done to compare control group compared with CHX treated group irrespective of bonding technique. Results: Surface treatment of Biodentine with 0.2% or 2% CHX reduced the bond strength of composite resin to Biodentine irrespective of bonding strategies. The One-way ANOVA test showed there was statistically significant difference in SBS of the resin composite bonded to Biodentine when the different bonding strategies and surface treatment are applied( p&lt;0.001 ). Two-way ANOVA test showed statistically significant difference in SBS between etching technique and different concentrations of CHX with p&lt;0.001. A higher SBS was observed when the Biodentine was pretreated with 0.2% CHX (Group 3 and Group 5) compared to 2% CHX (Group 4 and Group 6) (p&lt;0.001). Posthoc test statistically significant difference found in SBS when control groups when compared to groups treated with CHX, irrespective of bonding technique (p&lt;0.001). Conclusion: Application of 2% and 0.2% CHX on Biodentin reduced the SBS with resin composite, irrespective of the bonding strategy. Between the self-etch and etch-rinse adhesive system used in this study, etch-rinse showed higher SBS for 0.2% CHX compared to self-etch adhesive system.

Hydrogen (H 2 ) is a clean fuel with the potential to enable carbon-neutral energy systems. However, its large-scale application requires low-cost, efficient, and durable electrocatalysts for the hydrogen evolution reaction. Herein, we report a heterostructure consisting of niobium-doped molybdenum diselenide (Nb-MoSe 2 ) anchored on Nb 2 CT x MXene. Nb-MoSe 2 was synthesized via a hydrothermal route, while Nb 2 CT x was prepared through selective acid etching of Nb 2 AlC MAX phase. The heterostructure was assembled using a simple ultrasonication process. Nb-doping modifies the electronic environment of MoSe 2 and increases the density of catalytically active sites, while the Nb 2 CT x MXene provides a highly conductive scaffold to prevent particle agglomeration and facilitate rapid charge transfer. Electrochemical testing in acidic media reveals that the optimized Nb-MoSe 2 /Nb 2 CT x exhibits improved HER performance, achieving an overpotential of 287 mV at 10 mA cm −2 and 405 mV at 50 mA cm −2 , with a Tafel slope of 122 mV dec −1 and stable operation over 48 h using a carbon cloth substrate. Compared to Nb-MoSe 2 , Nb 2 CT x and MoSe 2 , the heterostructure shows enhanced catalytic activity, which is associated with the combined contribution of Nb-doped MoSe 2 and the conductive MXene support. This study offers a scalable approach to designing heterostructure electrocatalysts through doping and surface design for hydrogen technologies. • Nb-MoSe 2 /Nb 2 CT x formed by hydrothermal, etching and sonication strategies. • Nb doping tunes the electronic structure of MoSe 2 , enhancing its conductivity and active sites. • Conductive Nb 2 CT x MXene ensures fast charge transfer, high conductivity, and stability. • Delivers 287 mV at 10 mA cm −2 and 405 mV at 50 mA cm −2 with efficient HER activity. • Nb-MoSe 2 /Nb 2 CT x demonstrates good operational stability over 48 h in acid media.