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As high temperature corrosion of metel materials is common in the working environment of mechanical parts, it is of great practical significance to study the factors influencing the high temperature corrosion properties of metal materials. In this work, the macroscopic and microscopic factors affecting high temperature corrosion and the main countermeasures were reviewed and the mechanism of high temperature corrosion was summarized. The influence of water vapor (humidity) as well as the inhibition effect of pre - oxidation on high temperature corrosion were emphatically analyzed and the mechanism of high temperature corrosion in the environments containing water vapor was summarized. Based on the inductive research of a large number of literatures, it was revealed that in most cases the severity of spalling condition of the oxidation layer and the corrosion rate increased with the rise of the water vapor content. However, a few literatures reported that in the atmosphere containing water vapor, the corrosion rate was reduced and the corrosion resistance was improved. In addition, some special elements such as Pt, Y and Hf added into the material had a certain mitigation effect on the corrosion accelerated by water vapor. The pre - oxidation could form oxide layer on the surface of materials in advance and had an obvious effect on improving the anti - high - temperature corrosion properties of materials. This distinguished the pre-oxidation from viarous other methods uesd for the same purpose. In addition, the influencing rules of pre - oxidation duration, temperature and atmosphere on the anti - high - temperature corrosion properties were analyzed.

Graphene‐like materials were prepared by thermal copolymerization using melamine as a precursor, and chemical methods successfully synthesized Eu/g‐C3N4 composites containing different europium elements. Degradation rates of 64.3 %, 91.9 %, and 72.8 % were observed in the photocatalytic degradation of Pefloxacin, Enrofloxacin, and Ciprofloxacin under visible light (λ>550 nm). Determine the photocatalytic activity of the composite. When the doping amount was Eu/g‐C3N4‐2 with k=0.0135 min−1, four times greater than that of g‐C3N4, the best photocatalytic effect was obtained. Repeated studies revealed that the Eu/g‐C3N4 composite samples had good cycle stability, and a potential degradation process was postulated. [ABSTRACT FROM AUTHOR]

Silver nanoparticles (AgNPs) are known for their antibacterial properties and their ability to promote wound healing. By incorporating silver nanoparticles into medical gauze, the resulting composite material shows promise as an advanced wound dressing. However, clinical applications are hindered by challenges related to the stability of silver nanoparticle loading on the gauze as nanoparticle leaching can compromise antibacterial efficacy. In this study, silver nanoparticles were immobilized onto polydopamine (PDA) submicron particles, which were then used to modify medical gauze. Energy dispersive spectroscopy (EDS) was employed to analyze the elemental distribution on the modified gauze, confirming successful surface modification. The antibacterial properties of the modified gauze were assessed using a laser scanning confocal microscope (CLSM). The results demonstrated a significant reduction in the adhesion rates of Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) by 99.1% and 63%, respectively, on the PDA–Ag-modified gauze. Optical density (OD) measurements at 590 nm indicated that the modified gauze effectively inhibited biofilm formation, underscoring its potent antimicrobial capabilities. Further antibacterial efficacy was evaluated by diluting and plating co-cultured bacterial solutions with the modified dressing, followed by 24 h incubation and colony counting. The gauze exhibited an antibacterial efficiency of 99.99% against E. coli and 99.8% against S. aureus. Additionally, cell compatibility tests, involving the co-culture of PDA–Ag composites with human cells, demonstrated excellent biocompatibility. These findings suggest that PDA–Ag-modified medical gauze holds significant potential for the treatment of infected wounds, offering a promising solution to improve wound care through enhanced antimicrobial activity and biocompatibility. [ABSTRACT FROM AUTHOR]

A leaky-wave antenna (LWA) realizes radiation of travelling wave along guiding structures. Periodic modulation is an effective approach to turn non-radiating modes into radiating modes. A high-efficient LWA based on spoof surface plasmon polaritons (SSPPs) loaded with parasitic patch array is proposed. Sinusoidal modulation is used for the radiation of SSPPs, while parasitic array mitigates the open stopband (OSB) effect. A prototype is fabricated and measured. The measured and simulated results agree well with each other. Such design shows wide angle coverage of 83° from backward to forward and stable gain distribution of about 12 dB within the whole operating band.

This letter presents a novel unequal bandpass filtering power divider based on hybrid-mode of half mode substrate integrated waveguide (HMSIW) and spoof surface plasmon polaritons (SSPPs). Bandpass response is achieved by combining the transmission properties of HMSIW and SSPPs simultaneously. The operating bandwidth can be designed in a wide range by simply optimizing the dimensions of HMSIW and SSPPs. In addition, defected ground structures (DGSs) are etched on the bottom of the substrate to improve out-of-band suppression. The power division ratio of the proposed unequal power divider is finally optimized to 1:3. The measured results agree with the simulated one. Such design provides a stable power division within wide frequency range from 6.5 to 9.5 GHz.