Roles of Al and Mg on the Microstructure and Corrosion Resistance of Zn-Al-Mg Hot-Dipped Coated Steel.

In this work, a novel zinc-aluminum-magnesium (Zn-Al-Mg, ZM) coated steel was prepared using the hot-dip method. The microstructure and corrosion resistance of the ZM-coated steel were investigated. Compared to the conventional galvanized steel (GI), the ZM coating demonstrated a distinctive phase structure, consisting of Zn phase, binary eutectic (Zn/MgZn2), and ternary eutectic (Zn/Al/MgZn2). The corrosion resistance of the ZM-coated and GI-coated steels was evaluated by neutral salt spray test (NSST), polarization and electrochemical impedance spectroscopy (EIS). The results indicated that ZM-coated steel provided superior long-term corrosion protection in a NaCl environment compared to GI-coated steel. The scanning vibrating electrode technique (SVET) proved to be an effective method for investigating the evolution of the anodic and cathodic on the local coating surface. GI-coated steel exhibited a potential and current density distribution between the cathodic and anodic sites nearly three orders of magnitude higher than that of ZM-coated steel, suggesting a higher corrosion rate for GI-coated steel.

Self-healing, environmentally stable and adhesive hydrogel sensor with conductive cellulose nanocrystals for motion monitoring and character recognition.

Conductive hydrogel-based sensors offer diverse applications in artificial intelligence, wearable electronic devices and character recognition management. However, it remains a significant challenge to maintain their satisfactory performances under extreme climatic conditions. Herein, a stretchable, self-adhesive, self-healing and environmentally stable conductive hydrogel was developed through free radical polymerization of hydroxyethyl acrylate (HEA) and poly(ethylene glycol) methacrylate (PEG) as the skeleton, followed by the incorporation of polyaniline-coated cellulose nanocrystal (CNC@PANI) as the conductive and reinforced nanofiller. Encouragingly, the as-prepared hydrogel (CHP) exhibited decent mechanical strength, satisfactory self-adhesion, prominent self-healing property (95.04 % after 60 s), excellent anti-freezing performance (below -60 °C) and outstanding moisture retention. The assembled sensor derived from CHP hydrogel possessed a low detection limit (0.5 % strain), high strain sensitivity (GF = 1.68) and fast response time (96 ms). Remarkably, even in harsh environmental temperatures from -60 °C to 80 °C, it reliably detected subtle and large-scale human motion for a long-term process (>10,000 cycles), manifesting its exceptional environmental tolerance. More interestingly, this hydrogel-based sensor could be assembled into a "writing board" for accurate handwritten numeral recognition. Therefore, the as-obtained multifunctional hydrogel could be a promising material applied in human motion detection and character recognition platforms even in harsh surroundings.

Versatile CO2-responsive Sponges Decorated with ZIF-8 for Bidirectional Separation of Oil/Water and Controllable Removal of Dyes.

The complex wastewater containing water-soluble dyes and water-insoluble oils has given rise to significant environmental concerns that demand urgent remediation. Herein, a novel "smart" multifunctional sponge (ZIF-8@PMS) stepwise decorated with ZIF-8 nanoparticles and CO2-responsive copolymer (poly(2-(diethylamino) ethyl methacrylate-co-3-(trimethoxysilyl)propyl acrylate-co-stearyl methacrylate) was successfully prepared for CO2 controllable oil/water separation and dyes removal. The results revealed that the sponge coated with CO2-responsive copolymer for three cycles (ZIF-8@PMS-3) exhibited optimal comprehensive properties. The ZIF-8@PMS-3 had excellent compressive-resilient characteristics and chemical stability. As expected, it displayed tunable wettability and charged state under the regulation of CO2. Based on these features, ZIF-8@PMS-3 presented highly efficient removal of oil and dyes, even for the dye-containing oil/water emulsions, via a synergistic combination of adsorption and separation methods. The adsorption capacity for oil and various organic solvents ranged from 21.3 to 50 g g-1. The maximum adsorption capacities toward anionic dyes: methyl orange with 1205.89 mg g-1 and methyl blue with 880.00 mg g-1 in the presence of CO2 through electrostatic interaction. In the absence of CO2, it achieved maximum adsorption capacities for cationic dyes, including malachite green with 1246.15 mg g-1 and rhodamine B with 203 mg g-1, primarily driven by π-π interactions. According to distinct adsorption mechanisms, ZIF-8@PMS-3 could selectively adsorb either anionic or cationic dyes by exploiting CO2 as a trigger. Furthermore, the separation efficiencies for both types of oil/water emulsions surpassed 99.9%, with respective fluxes of 1566.99 L m-2 h-1 (water-in-oil emulsion) and 310.37 L m-2 h-1 (oil-in-water emulsion). Additionally, the as-prepared sponges exhibited remarkable antibacterial properties and exceptional recyclability. Therefore, the ZIF-8@PMS-3 holds substantial promise for potential applications in practical industrial wastewater treatment.

Multiple Bioactivities of Peptides from Hydrolyzed Misgurnus anguillicaudatus.

Misgurnus anguillicaudatus (loach) is a widely distributed benthic fish in Asia. In this study, the alkaline protease was used to hydrolyze loach, and the hydrolysate products of different molecular weights were obtained by membrane separation. In vitro antioxidant assays showed that the <3 kDa fraction (SLH-1) exhibited the strongest antioxidant activity (DPPH, hydroxyl radical and superoxide radical scavenging ability, and reducing power), while SLH-1 was purified by gel filtration chromatography, and peptide sequences were identified by LC-MS/MS. A total of six peptides with antioxidant activity were identified, namely SERDPSNIKWGDAGAQ (D-1), TVDGPSGKLWR (D-2), NDHFVKL (D-3), AFRVPTP (D-4), DAGAGIAL (D-5), and VSVVDLTVR (D-6). In vitro angiotensin-converting enzyme (ACE) inhibition assay and pancreatic cholesterol esterase (CE) inhibition assay, peptide D-4 (IC50 95.07 µg/mL, 0.12 mM) and D-2 inhibited ACE, and peptide D-2 (IC50 3.19 mg/mL, 2.62 mM), D-3, and D-6 acted as pancreatic CE inhibitors. The inhibitory mechanisms of these peptides were investigated by molecular docking. The results showed that the peptides acted by binding to the key amino acids of the catalytic domain of enzymes. These results could provide the basis for the nutritional value and promote the type of healthy products from hydrolyzed loach.

CO2-responsive functional cotton fibers decorated with Ag nanoparticles for "smart" selective and enhanced dye adsorption.

Novel Ag nanoparticles (NPs) decorated CO2-responsive cotton fiber (PCCF@Ag) as eco-friendly adsorbent was prepared via in-situ growth of Ag NPs on the poly(2-(dimethylamino) ethyl methacrylate-co-4-acryloyloxybenzophenone) coated cotton fiber. The as-prepared PCCF@Ag displayed excellent adsorption performance toward both anionic and cationic dyes with or without CO2 stimulation, even under a wide range of pH from 3 to 11. The maximum adsorption capacities of the as-prepared PCCF@Ag toward anionic dye (1538.5 mg g-1 for MO) and cationic dyes (944.0 mg g-1 for MEB and 415.6 mg g-1 for NR) were satisfactory. The adsorption processes were described better by the Langmuir isotherm and pseudo-second-order kinetic models, respectively. Notably, upon CO2 stimulation, the PCCF@Ag exhibited significantly enhanced adsorption capacity toward anionic dyes, following ultrafast adsorption rate, which made the PCCF@Ag could selectively adsorb anionic dyes from mixture because of greatly different adsorption rates between anionic dyes (adsorption equilibrium within 2 min) and cationic dyes (adsorption equilibrium over 12 h). Additionally, the PCCF@Ag could maintain over 91.0% of adsorption capacity even after ten cycles, indicating its outstanding reusability. Meanwhile, the as-obtained PCCF@Ag exhibited excellent antibacterial activity. Overall, the as-obtained PCCF@Ag could be considered as a promising dye scavenger for wastewater remediation.

Facile and Scalable Fabrication of Antibacterial CO2-Responsive Cotton for Ultrafast and Controllable Removal of Anionic Dyes.

A novel CO2-responsive cotton as an eco-friendly adsorbent derived from poly(4-acryloyloxybenzophenone-co-2-(dimethylamino) ethyl methacrylate) and cotton was fabricated via a facile and fast dip-coating method. As expected, upon CO2 stimulation, the protonated cotton presented CO2-induced "on-off" selective adsorption behaviors toward anionic dyes owing to electrostatic interactions. The adsorption isotherms and kinetics of the CO2-responsive cotton toward anionic dyes obeyed the Langmuir isotherm and pseudo-second-order kinetics models, respectively. It is noteworthy that the CO2-responsive cotton exhibited high adsorption capacity and ultrafast adsorption rate toward anionic dyes with the maximum adsorption capacities of 1785.71 mg g-1 for methyl orange (MO), 1108.65 mg g-1 for methyl blue (MB), and 1315.79 mg g-1 for naphthol green B (NGB), following the adsorption equilibrium times of 5 min for MO, 3 min for MB, and 4 min for NGB. Moreover, the CO2-responsive cotton also exhibited high removal efficiency toward anionic dyes in synthetic dye effluent. Additionally, the CO2-responsive cotton could be facilely regenerated via heat treatment under mild conditions and presented stable adsorption properties even after 15 cycles. Finally, the as-prepared CO2-responsive cotton exhibited outstanding antibacterial activity against E. coli and S. aureus. In summary, this novel CO2-responsive cotton can be viewed as a promising eco-friendly adsorbent material for potential scalable application in dye-contaminated wastewater remediation.

Influence of fluorinated graphene-modified epoxy coatings on the corrosion behaviour of 2024 aluminium alloy.

This study provides an enhanced corrosion resistance of epoxy resin (EP) by embedding fluorinated graphene (FG) into the epoxy matrix. FG with different fluorine contents was obtained by reacting nitrogen trifluoride (NF3) gas with GO and then incorporated into the EP matrix to fabricate the different composites. Through a series of characterization methods, the chemical composition and microstructures of FG were systematically analyzed, and its corrosion resistance was also studied. Results revealed that F atoms were bonded to the GO surface to form C-F covalent bonds, and an FG lamellar thickness less than 2 nm. The contact angle of the coatings increased with the incorporation of FG, and the coating resistance of FG2/EP coating was 3 orders of magnitude more than that of the EP coating after immersion for 4080 h. Thus, the incorporation of FG into epoxy matrix significantly enhanced its hydrophobic properties and barrier performance, which was beneficial to improving the long-term corrosion resistance of the coating.