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• Ni(OH) 2 nanoflowers were prepared on Ti mesh using rapid electrodeposition. • Ni(OH) 2 /Ti exhibited excellent OER catalytic activity (η 100 = 290 mV). • Flowerlike Ni 2 P/Ti showed outstanding HER performance over the full pH range. • DFT calculation confirm that Ni and P as active sites have the best |Δ G H* |. • The Ni 2 P/Ti (−) || Ni(OH) 2 /Ti (+) displayed a low voltage of 1.493 V at 10 mA cm−2. The exploration of efficient, robust and nonprecious transition metal electrocatalysts for electrochemical hydrolysis is urgently needed. Herein, we developed Ni(OH) 2 with 3D nanoflower structure on the titanium mesh by a simple electrodeposition method. The Ni(OH) 2 /Ti exhibited excellent oxygen evolution reaction performance and achieved 10 mA cm−2 at 190 mV with fast kinetics in alkaline conditions. Ni 2 P, NiS 2 and NiSe 2 were prepared by solid-phase reaction, and the 3D nanoflower increased the open structure and greatly enhanced catalytic activity. The Ni 2 P/Ti electrode required an overpotential of 52, 88 and 109 mV to reach 10 mA cm−2 for hydrogen evolution reaction in acidic, alkaline and neutral media, respectively. The results of electrochemical measurements and mechanistic studies showed that the catalytic activity of HER: Ni 2 P > NiS 2 > NiSe 2 > Ni(OH) 2. The Ni 2 P/Ti and Ni(OH) 2 /Ti electrodes were assembled into an integrated water splitting electrolytic cell. The water electrolysis device assembled with the Ni 2 P/Ti and Ni(OH) 2 /Ti electrodes only needed a low potential of 1.608 V to achieve 50 mA cm−2 in alkaline environment and was operated stably for 50 h. [ABSTRACT FROM AUTHOR]

Graphical abstract The UC luminescence propertiesand mechanism are analyzed under excitation of 1064 nm and 1550 nm for the first time. The UC luminescence mechanism of the samples excited by 1064 nm laser is shown in Fig. 1(a) and (b). The results show that the intense green emission at 541 nm and 548 nm originates from the 4F 9/2 →4I 15/2 transition of Ho3+ ions and the 4S 3/2 →4I 15/2 transition of Er3+ ions. The weak green emission at 523 nm derives from the 2H 11/2 →4I 15/2 transition of Er3+ ions and the weak red emission at 653 nm and 667 nm originates from the 5F 5 →5I 8 transition of Ho3+ ions and the 4F 9/2 →4I 15/2 transition of Er3+ ions. The UC luminescence mechanism of the samples excited by 1064 nm laser is shown in Fig. 1(c) and (d). The results present that the green emission at 546 nm derives from the 5F 4 (5S 2 )→5I 8 transition of Ho3+ ions and the 4S 3/2 →4I 15/2 transition of Er3+ ions. On the other hand, the weak red emission at 653 nm and 667 nm derives from the 5F 5 →5I 8 transition of Ho3+ ions and the 4F 9/2 →4I 15/2 transition of Er3+ ions. (a) Energy level diagram for Ho3+, Er3+ and Yb3+ ions excited by 1064 nm. (b) Scheme of cross-relaxation between Ho3+ and Er3+ ions. (c) Energy level diagram for Ho3+, Er3+ and Yb3+ ions excited by 1550 nm. (d) Scheme of cross-relaxation between Ho3+ and Er3+ ions. Highlights • In this paper, PbF 2 : Ho3+, Er3+, Yb3+ phosphors are prepared by a high-temperature solid-state method for the first time. • The crystal structure of the as-prepared phosphors is refined. • The upconversion luminescence properties and mechanism of the as-prepared phosphors are analyzed under excitation of 1064 nm, 1550 nm for the first time. Abstract In this paper, PbF 2 : Ho3+, Er3+, Yb3+ phosphors are prepared by a high-temperature solid-state method. The crystal structure acquired by X ray powder diffractometer shows that the resultant phosphor is a pure cubic PbF 2 crystal. The upconversion (UC) emission spectra of samples are performed by a fluorescence spectrophotometer coupled with lasers of 980 nm, 1064 nm and 1550 nm, presenting the green emission in the range of 541∼548 nm and red emission in the range of 653–667 nm, corresponding to the excitation path: Ho3+: 4F 9/2 →4I 15/2 , Er3+: 4S 3/2 →4I 15/2 , Er3+: 4F 9/2 →4I 15/2 and Ho3+: 5F 5 →5I 8. Finally, the UC luminescence mechanism is analyzed under excitation of different wavelengths. The result shows that the phosphors have a promising prospect for application in anti-counterfeiting technologies and solar cell field. [ABSTRACT FROM AUTHOR]

VRK1 is a member of the vaccinia-related kinase (VRK) family of serine/threonine protein kinases, which is known to play multiple roles in cellular proliferation, cell cycle regulation and carcinogenesis. However, the expression and physiological significance of VRK1 in hepatocellular carcinoma (HCC) remain unclear. In this study, we aimed to investigate the potential role of VRK1 in the development and progression of HCC. Western blot and immunohistochemical analysis revealed that VRK1 was highly expressed in HCC tissues and cell lines, compared with adjacent nontumorous tissues and LO2 normal hepatocytes. Meanwhile, clinicopathological analysis showed that VRK1 was significantly associated with AJCC stage, Ki-67 and a poor prognosis in HCC specimens. Univariate and multivariate analysis showed that VRK1 could serve as an independent prognostic indicator of HCC patients’ survival. Furthermore, we found that VRK1 was lowly expressed in serum-starved Huh7 cells, and was progressively increased after serum-refeeding. Finally, flow cytometry, CCK-8 and colony formation assay indicated that the depletion of VRK1 could retard cell cycle progression and reduce cells proliferation in HCC cells. On the basis of these findings, we conclude that VRK1 may be a candidate prognostic biomarker as well as a potential therapeutical target of HCC. [ABSTRACT FROM AUTHOR]