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Aluminum alloys with low density and high specific strength have been widely used in marine engineering. Epoxy coatings, a simple and economical protection strategy, have been applied on alloy surfaces to prolong service life. However, a pure epoxy coating cannot provide long-term protection for metals in the marine environment. Hence, in this work, nano-alumina (nano-Al2O3) modified by polyethyleneimine (PEI) were added into epoxy coatings to enhance anticorrosion properties. Using Fourier transform infrared spectroscopy (FTIR), we found that the molecular chain of PEI was successfully grafted on the surface of nano-Al2O3, and the cross profile of coatings indicated that the modified nano-Al2O3 uniformly dispersed in the epoxy coating. Electrochemical impedance spectroscopy (EIS) results demonstrate that the coating resistance of the modified epoxy nanocomposite coating was 10 times higher than that of the pure epoxy coating after 3 days of immersion in 3.5 wt.% NaCl solution. Meanwhile, the surface morphologies and EDS-mapping of substrates after EIS testing show that the substrate coated with modified epoxy nanocomposite coating had the smallest amount of corrosion products. These results show that this modified epoxy nanocomposite coating has excellent anticorrosion performance.

Being the target of negative school gossip, a form of relational aggression, has been shown to be associated with psychological and behavioral problems in youth adolescents. Based on the experience avoidance model, this study tested the association between negative school gossip and youth adolescents’ mobile phone addiction, and the serial mediation roles of anxiety and experience avoidance in this relationship. Junior high school students (N = 837; ages 12–15; 50% girls) completed the Negative School Gossip Scale, Anxiety Scale, Acceptance and Action Questionnaire (AAQ-II), and Mobile Phone Addiction Scale in their classrooms. The results of regression-based analyses showed that after controlling for age and gender, (1) negative school gossip was significantly associated with mobile phone addiction; (2) anxiety and experience avoidance each significantly mediated this association; (3) anxiety and experience avoidance serially mediated this association. The results support the experience avoidance model and highlight emotional factors as an internal mechanism by which negative school gossip is associated with youth adolescents’ mobile phone addiction. The results also have implications for preventing and reducing youth adolescents’ mobile phone addiction.

In this work, the treatment of bio-treated coking wastewater (BCW) by catalytic ozonation was conducted in semi-batch and continuous flow reactors. The kinetics of chemical oxygen demand (COD) removal were analyzed using BCWs from five coking plants. An integral reactor with catalytic ozonation stacked by ozone absorption (IR) was developed, and its efficiency was studied. The catalyst of MnxCe1-xO2/&gamma, Al2O3 was efficient in the catalytic ozonation process for the treatment of various BCWs. The chemical oxygen demand (COD) removal efficiencies after 120 min reaction were 64&ndash, 74%. The overall apparent reaction rate constants were 0.0101&ndash, 0.0117 min&minus, 1, which has no obvious relationship with the initial COD of BCW and pre-treatment biological process. The IR demonstrated the highest efficiency due to the enhancement of mass transfer and the utilization efficiency of ozone. Bypass internal circulation can further improve the reactor efficiency. The optimal results were obtained with the ozone absorption section accounting for 19% of the valid water depth in the reactor and 250% of circulation flow ratio. The long-term and full-scale application of the novel reactor in a continuous mode indicated stable removal of COD and polycyclic aromatic hydrocarbons (PAHs). The results showed that the system of IR is a promising reactor type for tertiary treatment of coking wastewater by catalytic ozonation.

The fabrication and luminescent performance of novel phosphors Na2YMg2V3O12:Dy3+ were investigated by a conventional solid-state reaction method. Under near-UV light, the Na2YMg2V3O12 host self-activated and released a broad emission band (400&ndash, 700 nm, with a peak at 524 nm) ascribable to charge transfer in the (VO4)3&minus, groups. Meanwhile, the Na2YMg2V3O12:Dy3+ phosphors emitted bright yellow light within both the broad emission band of the (VO4)3- groups and the sharp peaks of the Dy3+ ions at 490, 582, and 663 nm at a quenching concentration of 0.03 mol. The emission of the as-prepared Na2YMg2V3O12:Dy3+ phosphors remained stable at high temperatures. The obtained phosphors, commercial Y2O3:Eu3+ red phosphors, and BaMgAl10O17:Eu2+ blue phosphors were packed into a white light-emitting diode (WLED) device with a near-UV chip. The designed WLED emitted bright white light with good chromaticity coordinates (0.331, 0.361), satisfactory color rendering index (80.2), and proper correlation to a color temperature (7364 K). These results indicate the potential utility of Na2YMg2V3O12:Dy3+ phosphor as a yellow-emitting phosphor in solid-state illumination.

Acid-washed activated carbon (AC-A), nitric acid modified activated carbon (AC-NO2), aminated activated carbon (AC-NH2) and cerium-loaded activated carbon (Ce/AC) were prepared and characterized by BET procedure, Boehm titration and SEM. Their performances were investigated for the ozonation of p-chlorobenzoic acid (p-CBA) in its solution and organic compounds in reverse osmosis concentrate (ROC). Nitration and amination had little effect on the surface area of catalyst, but increased the concentration of surface acid and basic functional group respectively. After loading Ce, the surface area of the catalyst decreased, and amount of Ce particles were agglomerated on the surface of activated carbon. All the four catalysts can improve the removal rate of the organics in water. Among the four catalysts, Ce/AC shows the highest catalytic activity. The removal rates of p-CBA, TOC and three target pollutants (e.g., tetracycline, metoprolol, atrazine) are 99.6%, 70.38%, 97.76%, 96.21% and 96.03%, respectively. Hydroxyl radical (&middot, OH) was proved to be the core of catalytic reaction mechanism for Ce/AC, with the contribution rate to p-CBA removal of 91.4%. The surface groups and the Ce loaded on AC were the initiator for the rapid generation of &middot, OH. Electron transfer between electron-rich structures and cerium oxide might be a synergistic effect that can increase catalytic activity of Ce loaded on AC. Catalytic ozonation with Ce/AC is a promising ROC treatment technology due to its efficiency and possibilities for improvement.