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《Journal of dairy science》2022,105(3):1966-1977
Aflatoxin M1 (AFM1) is a common toxin in dairy products that causes acute and chronic human health disorders. Thus, the development of a rapid and accurate AFM1 detection method is of vital importance for food safety monitoring. This work was to develop a novel electrochemical aptasensor for sensitive and specific determination of AFM1. The dendritic-like nanostructure was formed on the gold electrode surface by layer-by-layer assembly of gold-silver core-shell nanoparticles modified with DNA conjugates. In the presence of AFM1, the specific recognition between AFM1 and Apt caused the disassociation of the DNA controlled dual Au@Ag conjugates from the surface of the electrode, causing less methylene blue to bind to the surface and weakening the electrochemical signal. The more AFM1 there is, the weaker the electrochemical signal. Transmission electron microscope results showed that the successfully synthesized Au@Ag nanoparticles exhibited a core-shell structure with Au as core and Ag as shell, and their average diameter was about 30 nm. Under optimal conditions, the electrochemical aptasensor showed a wide detection ranging from 0.05 ng mL?1 to 200 ng mL?1, and a low detection limit of 0.02 ng mL?1. Moreover, the proposed strategy has been successfully applied to the detection of AFM1 in cow, goat, and sheep milk samples with satisfactory recoveries ranging from 91.10% to 104.05%. This work can provide a novel rapid detection method for AFM1, and also provide a new sensing platform for the detection of other toxins. 相似文献
63.
Lithium‐sulfur batteries have attracted much research interest because of their high theoretical energy density and low‐cost raw materials. While the electrodes are composed of readily available materials, the processes that occur within the cell are complex, and the electrochemical performance of these batteries is very sensitive to a number of cell processing parameters. Herein, a simple electrochemical model will be used to predict, with quantitative agreement, the electrochemical properties of lithium‐sulfur cathodes with varying carbon to sulfur ratios. The discharge capacity and the polarization were very similar for the lowest sulfur loadings, while above 23.2 wt% sulfur the gravimetric capacity dropped significantly, and there was an increase in the cell polarization. In addition, a transition in the electrode morphology, from well dispersed to aggregated sulfur at the surface, will be reflected in the change in a critical model parameter demonstrating the sensitivity and functionality of even this simple model in predicting complex behavior in the lithium‐sulfur cells. 相似文献
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Norman Kauss Andreas Heyn Oliver Michael Michael Schymura Paul Rosemann 《工业材料与腐蚀》2021,72(10):1656-1667
Nickel-free high-nitrogen-alloyed stainless steels like the P2000 (X13CrMnMoN18-14-3) were developed to enhance the strength and corrosion resistance of austenitic stainless steels like 304 and 316 while keeping the typical high ductility. The mechanical and corrosive properties of P2000 were investigated and compared with 304 and 316 to highlight the application opportunities of this new alloy. The microstructure of the solution-annealed condition was characterised by electron backscatter diffraction and the mechanical properties were studied by uniaxial tensile tests, Charpy impact tests and hardness measurements. The passivation behaviour was analysed using the electrochemical potentiodynamic reactivation, whereas the pitting corrosion resistance was compared by pitting potentials and pitting temperatures. However, secondary thermal influences or suboptimal heat treatment can impair the corrosion resistance due to the precipitation of secondary phases and the resulting sensitisation. Thermodynamic calculations and artificial ageing treatment in the range of 500–900°C for up to 100 h were used to determine critical time–temperature parameters for sensitisation. The microstructure of the various aged states was evaluated by scanning electron microscopy and compared with the degrading corrosion resistance characterised by the KorroPad method. 相似文献
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Lorenzo Mardegan Chris Dreessen Michele Sessolo Daniel Tordera Henk J. Bolink 《Advanced functional materials》2021,31(42):2104249
The choice of an adequate electrolyte is a fundamental aspect in polymer light-emitting electrochemical cells (PLECs) as it provides the in situ electrochemical doping and influences the performance of these devices. In this study, a hyperbranched polymer (Hybrane DEO750 8500) blended with a Li salt is used as a novel electrolyte in state-of-the-art Super Yellow (a polyphenylenevinylene) based LECs. Due to the desirable properties of the hyperbranched polymer and the homogeneous and smooth films that it forms with the emitting polymer, PLEC with excellent electroluminescent properties are obtained using a pulsed current bias scheme. The devices are very stable, with lifetimes in excess of 2000 h with initial luminance values above 450 cd m−2, a peak efficiency of 12.6 lm W−1, and sub-minute turn-on times. The stability of the devices is also studied by measuring the photoluminescence (PL) of the semiconductor during electroluminescent operation. The findings suggest that it is possible to observe the quenching of the PL in vertically stacked devices due to the advancement of the doped fronts in the film and an immediate PL recovery when the bias is removed. 相似文献
68.
Hai Chi Yujie Li Guoqin Liu 《International Journal of Food Science & Technology》2022,57(8):5376-5387
In this study, a new electrochemical strategy based on the fabrication of a molecularly imprinted sensor onto a MoS2-loaded peanut shell carbon complex with gold nanoparticles (AuNPs) and nitrogen-doped carbon dots (N-CDs) was proposed for the detection of benzo(a)pyrene (BaP). Molecularly imprinted polymer (MIP) films were prepared by cyclic voltammetry (CV) using 2-mercaptobenzimidazole (2-MBI) as a functional monomer in the presence of BaP. The surface morphologies, structural characteristics and electrochemical properties of the obtained MIP/AuNPs/N-CDs/PSBC/MoS2/GCE were investigated via scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy-dispersive spectrometry (EDS), Fourier transform infrared spectrometry (FTIR), X-ray diffraction (XRD), UV–Vis spectrometry, fluorescence spectrometry, cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS). Under the optimised conditions, the detection range of the electrode towards BaP varied from 5 nM to 20 μM with a detection limit of 1.5 nM. The prepared electrochemical sensor also exhibited good stability, relevant reproducibility and high selectivity. The application of the sensor in the actual analysis of edible oil samples showed promising results, thereby being relevant as a biomimetic sensing platform for the detection of chemical hazards in food and environment. 相似文献
69.
In this paper, we demonstrated the processing of Li7La3Zr0.5Nb0.5Ta0.5Hf0.5O12 (LLZNTH) high-entropy Li–garnet with promising properties for lithium batteries. We first synthesized the LLZNTH Li–garnet powders which have a single cubic garnet phase (space group: ; No. 230) without any secondary phases as well as uniform elements distributions. The prepared powders were further densified to a relative density of ∼94% with well-crystallized grains and good contact with the neighboring grains. Minimal grain growth can be observed in the sintering time range from 8 to 20 h, which is likely due to the sluggish effects of high-entropy compounds. The sample also maintains the cubic garnet phase along with uniform elements distribution after sintering. Electrochemical characterizations indicate that the densified sample has an adequate ionic conductivity of 4.67 × 10−4 S cm−1 at room temperature, a low activation energy of 0.25 eV, and a low electronic conductivity in the order of 10−8 S cm−1. The significance of designing high-entropy electrolyte is further discussed. 相似文献
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