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The dealloying corrosion behavior of the FCC Ni20Cr (wt%) in molten LiF-NaF-KF (FLiNaK) salts at 600 °C under varying applied potentials was investigated. Using in-operando electrochemical techniques and a multi-modal suite of characterization methods, we connect electrochemical potential, thermodynamic stability, and electro-dissolution kinetics to the corrosion morphologies. Notably, under certain potential regimes, a micron-scale bicontinuous structure, characterized by a network of interconnected pores and ligaments riched with the composition of the more noble (MN) element, becomes prominent. At other potentials both MN and less noble (LN) elements dealloy but at different rates. The dealloying process consists of lattice and grain boundary diffusion of Cr to the metal/salt interface, interphase Cr oxidation, accompanied by surface diffusion of Ni to form interconnected ligaments. At higher potentials, the bicontinuous porous structure undergoes further surface coarsening. Concurrently, Cr(II), Cr(III), and Ni(II) begin to dissolve, with the dissolution of Ni occurring at a significantly slower rate. When solid-state transport of Cr is exceeded by the interfacial rates, dealloying depths are limited.

Corrosion processes are often discussed as stochastic events. Here, it is shown that some of these seemingly random processes are not driven by nanoscopic fluctuations but rather by the spatial distribution of micrometer‐scale heterogeneities that trigger fast reactions associated with corrosion. Using a novel excitable reaction‐diffusion model, corrosion waves traveling over the metal surface and the associated material loss are described. This resulting nonuniform corrosion penetration, seen as a height loss in modeling, exposes buried intermetallic particles, which depending on the local electrochemical state of the surface trigger or block new waves. Informed by quantitative experimental data for the Mg–Al–Zn alloy AZ31B, wave speeds, wave widths, and average material loss are accurately captured. Morphogenic mitigation based on wave‐breaking microparticles is also simulated. While AZ31B corrosion is identified as a process driven by rare‐wave events, this study predicts several other corrosion regimes that proceed via spots or patchy patterns, opening the door for new protection, design, and prediction strategies. [ABSTRACT FROM AUTHOR]

The utilization of electroplating sludge (ES) to derive metal oxide functional materials is a key strategy, as it enables the recycling of valuable elements, mitigates environmental risks, and aligns with green, low-carbon development strategies. Nevertheless, the development of metal oxide composite functional materials with distinctive structures and properties derived from ES continues to present several challenges. Herein, we synthesized CuFe2O4/MgFe2O4 metal oxide composites from ES by one-step hydrothermal method. As-obtained CuFe2O4/MgFe2O4 metal oxide composites (MMOs) have a unique layered structure, richer mesoporous and microporous structures, activity sites. When evaluated as an adsorbent for Congo red (CR), as-synthesized CuFe2O4/MgFe2O4 with layered structure composite exhibited excellent adsorption capacity (1039.1 mg/g) and reusability (85.55% after five cycles), which was superior to most similar adsorbents reported till date. Such improvement is explored to mainly originate from two respects: the physical adsorption facilitated by the abundant pores formed through the stacking and growth of CuFe2O4 and MgFe2O4, and the chemisorption resulting from surface complexation and hydrogen bonding between the MMOs and CR. This strategy to directly transform ES into functional materials shows great promise both in waste management and preparation of robust adsorbents for wastewater treatment. [ABSTRACT FROM AUTHOR]

Aflatoxin B1 (AFB1) contamination poses a fatal risk to human beings and urgently needs highly sensitive detection for environmental monitoring and food safety. However, the existing challenges are the unsatisfied sensitivity of the immunoassay methods and the complex matrix effect. Rolling circle amplification (RCA) is a promising method for nucleic acid isothermal amplification due to its high specificity and sensitivity. Herein, we constructed a general RCA-based point-of-care test method (RCA−POCT). With biotinylated antibodies, streptavidin, and biotinylated RCA primers, we realized the signal transduction and preliminary signal amplification. In this way, the fluorescent signal of the immunocomplex on the microwells was greatly enhanced. Under optimal conditions, we recorded sensitive detection limits for aflatoxin B1 (AFB1) of 1.94, 16.3, and 37.7 fg/mL (femtogram per microliter), and wide linear ranges with 5 × 10−6 to 5, 5 × 10−5 to 5, and 5 × 10−5 to 5 ng/mL in the irrigation water, field soil, and peanut samples, respectively. Satisfactory recovery, specificity, repeatability, and reproducibility were observed. The RCA−POCT was validated by comparing it to the HPLC method. This work provides a general RCA-assisted detection method for AFB1 in the environment and food. [ABSTRACT FROM AUTHOR]

Pursuing of straightforward and cost‐effective methods for synthesizing high‐performance anode materials for lithium‐ion batteries is a topic of significant interest. This study elucidates a one‐step synthesis approach for a conversion composite using glow discharge in a nickel formate solution, yielding a composite precursor comprising metallic nickel, nickel hydroxide, and basic nickel salts. Subsequent annealing of the precursor facilitated the formation of the Ni@NiO composite, exhibiting exceptional electrochemical properties as anode material in Li‐ion batteries: a capacity of approximately 1000 mAh g−1, cyclic stability exceeding 100 cycles, and favorable rate performance (200 mAh g−1 at 10 A g

The development of hybrid agro-metallic alloy and its composites has increased in the last few years to overcome the shortcomings of monolithic alloys. Using hard ceramic reinforcements would enhance the strength of the alloys and its composites during component building. One such ceramic reinforcement is the Titania (TiO2) powder, which possesses more strength than other ceramics materials, but the cost is a little higher. To overcome this, eco-friendly, calcined eggshell (CES) particulates are added to TiO2 reinforcement to enhance the strength of the hybrid composite at a reduced cost. The main novelty of the present study is the employment of CES and TiO2 particulates in the Al 6061 matrix during the development of hybrid Al 6061 composites. This increases the strength of the fabricated composites at a reduced cost and results in the development of eco-friendly agro-metallic composites. Samples were produced individually in groups with varying proportions of CES at 3, 6, 9 and 12 wt% and combined with fixed proportions of TiO2 at 3, 6, 9 and 12 wt% individually with groups such as A (3 wt% of TiO2 + 3, 6, 9 and 12 wt% of CES), B, C and C and D, respectively. Microstructural characterization through FESEM and phase identification through XRD analysis are conducted to justify the uniform dispersion of reinforcements in the matrix. Developed samples were subjected to tensile, flexural and hardness tests, and the results proved that the mechanical properties of composites were enhanced when combining 3, 6, 9 and 12 wt% CES with 3 and 6 wt% of TiO2 compared with unreinforced Al 6061. The enhancement is linked to the uniform dispersion of the particles and good interaction between the particles. However, the 3, 6, 9 and 12 wt% CES with 9 and 12 wt% of TiO2 yielded inferior strength performance relative to the reference mix due to particle clustering and agglomeration formation. This acts as a yielding point for stress concentration. Therefore, it was concluded that a combination of 3, 6, 9 and 12 wt% CES with TiO2 should not exceed 6 wt% of TiO2. [ABSTRACT FROM AUTHOR]

Latex of C. gigantea was used to synthesize zinc oxide nanoparticles (ZnO NPs) by the green chemistry approach. The crystalline size, shape, and purity of as-synthesized ZnO NPs were characterized through scanning electron microscopy with energy-dispersive X-ray spectroscopy, transmission electron microscopy, X-ray diffraction analysis, and Fourier-transform infrared spectroscopy techniques. Crystalline, spherical ZnO NPs with an average size of 21.8 nm were formed. In addition, the biological properties of the ZnO NPs, such as antioxidant and antibacterial activity, were evaluated by 2,2-diphenyl-1-picrylhydrazyl assay and the agar well-diffusion method. The highest free radical scavenging activities of 83.11 ± 1.89 % were observed at a concentration of 350 μg/mL of C. gigantea latex-mediated ZnO NPs. The latex in the C. gigantea latex-mediated ZnO NPs inhibited the growth of pathogenic bacteria. The maximum zone of inhibition was found in P. aeruginosa and S. aureus. C. gigantea latex-mediated ZnO NPs have significant biocompatibility and broad-spectrum antibacterial properties against wound-causing bacteria and, therefore, can be suggested for use in the formulation of novel creams or gels for healing applications. [ABSTRACT FROM AUTHOR]