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It is a crucial factor for enhancing upconversion luminescence (UCL) by doping different metals under irradiation. In this article, a series of Na3Gd(VO4)2:Ln3+ (NGVO:Ln3+) were prepared by sol–gel means with citrate and characterized using X-ray diffraction. Their UCL properties were systematically investigated. A wide multi-colour emission corresponding to different Ln3+ (Yb3+/Er3+/Tm3+/Ho3+) doping was obtained under single-wavelength excitation. It is worth pointing out that among all the studied samples, only the UCL intensity of NGVO:15%Yb3+/2%Er3+ was 1.74 times more than that of the sum under the excitation at 980 and 1550 nm due to the synergistic effect under simultaneous 980 and 1550 nm excitation. Interestingly, a higher Sa (5.54 × 10−3 K−1) for NGVO:15%Yb3+/2%Er3+ excited at 1550 nm could be obtained, which had an advantage over that at 980 nm excitation. The possible energy transfer mechanism of NGVO:15%Yb3+/2%Er3+ under single- and multi-wavelength excitation was also discussed in detail using an energy level diagram. To further improve the UCL intensity, NGVO:15%Yb3+/2%Er3+ doped with other rare-earth ions (La3+/Lu3+/Y3+) were synthesized, and their UCL intensity and Sa values were also improved to a certain extent. [ABSTRACT FROM AUTHOR]

Pyridine oximes produced from aldehyde or ketone with hydroxylamine (NH2OH) have been widely applied in pharmaceutics, enzymatic and sterilization. However, the important raw material NH2OH exhibits corrosive and unstable properties, leading to substantial energy consumption during storage and transportation. Herein, this work presents a novel method for directly synthesizing highly valuable pyridine oximes using in situ generated NH2OH from electrocatalytic NO reduction with well‐design nanofiber membranes (Al‐NFM) derived from NH2‐MIL‐53(Al). Particularly, 2‐pyridinealdoxime, the precursor of antidote pralidoxime (2‐PAM) for nerve agents suffering from scarcity and high cost, was achieved with a Faraday efficiency up to 49.8 % and a yield of 92.1 %, attributing to the high selectivity of NH2OH production on Al‐NFM, further easily reacted with iodomethane to produce 2‐PAM. This study proposes a creative approach, having wide universality for synthesizing pyridine and other oximes with a range of functional groups, which not only facilitates the conversion of exhaust gas (NO) and waste water (NO2−) into valuable chemicals especially NH2OH production and in situ utilization through electrochemistry, but also holds significant potential for synthesis of neuro detoxifying drugs to humanity security. [ABSTRACT FROM AUTHOR]

Purpose: To determine the histological effects of ultraviolet light and cold atmospheric plasma treatment on the osseointegration of titanium implants in vivo. Materials and methods: Six juvenile pigs were divided into three groups of two animals each. A total of 54 titanium implants were placed randomly in the pigs’ calvarial bone (nine implants per pig). Of these, 18 implants served as untreated controls. The remaining 36 implants served as the experimental group and were treated with either ultraviolet light or argon plasma for 12 minutes each prior to insertion. Two pigs in each group were kept until 2, 4 and 8 weeks and then sacrificed. Resonance frequency analysis was conducted after implant placement and at the time of sacrifice. Osseointegration was evaluated using microcomputed tomography scans and histomorphometrical analysis. Results: After initial loss, all implants showed a constant increase in implant stability quotient values over time without significant differences between the groups. The bone–implant contact values increased steadily for all implants over 8 weeks of healing. Surface-treated implants showed significantly higher bone–implant contact values compared to untreated implants at each time point. Bone area fraction occupancy values were almost always higher following both treatment methods; however, differences were only significant after 4 and 8 weeks for the cold atmospheric plasma group and after 4 weeks for the ultraviolet light group. Conclusions: Ultraviolet light and cold atmospheric plasma may improve histomorphometrical osseointegration of titanium implants significantly. [ABSTRACT FROM AUTHOR]