New mononuclear and dinuclear Ru­(II) coordination compounds with the 2,7-bisbenzoimidazolyl-naphthyridine ligand have been synthesized and characterized by UV–vis, NMR, and MALDI-TOF. The molecular structures for Ru­(II) compounds were determined by single-crystal X-ray diffraction. With the expansion of ligand π-conjugation and the increase in the complexed Ru number, the maximum emission wavelength red-shifted from 696 to 786 nm. The binding mode between complexes and DNA was predicted by molecular docking, which is intercalations and π–π stacking interactions with the surrounding bases. The intercalation mode of DNA binding was then determined by DNA titration and ethidium bromide (EB) displacement experiments. The antigrowth effects of complexes RuY, RuY1, and RuY2 were tested in HaCat (normal cells), HeLa (cervical cancer), A549 (lung cancer), and A549/DDP (cisplatin-resistant lung cancer) through the MTT assay. The dinuclear complex RuY2 was superior to mononuclear complexes and cisplatin in the cisplatin-resistant cell line. Confocal imaging proved that the subcellular localization of Ru­(II) complexes was mitochondria; moreover, apoptosis was detected by flow cytometry. All three complexes showed a dose-dependent manner in all four cell lines. All Ru­(II) complexes were found to have reactive oxygen species (ROS). The finding indicated that these Ru­(II) complexes caused cell death by both DNA disruption and ROS. This study helps to explore the potential of the polynuclear Ru­(II) complexes for the combination of NIR imaging and Pt-resistant cancer therapy.

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Strontium zirconate (SrZrO3) has been considered as a promising thermal barrier coating (TBC) material for application in gas turbine engines; however, the phase transition problem limits its application. In this study, an Yb2O3 and Gd2O3 codoped SrZrO3 system with excellent properties was reported. Yb2O3‐Gd2O3 codoped SrZrO3 ceramic powders [Sr0.8(Zr0.9Yb0.05Gd0.05)O2.75, SZYG/YGZO], [Sr(Zr0.9Yb0.05Gd0.05)O2.95, SZYG] and pure SrZrO3 (SZO) powders were produced by a conventional solid‐state reaction method. The XRD and Raman results show that, the composite SZYG/YGZO ceramics consist of the SZO and Yb0.5Zr0.5O1.75 phases with a low thermal conductivity of ~1.3 W/(m·K) at 1000°C, which is at least 40% lower than that of the SZO ceramics. The TG‐DSC results show that the SZYG/YGZO ceramics have no phase transition in the temperature range of 600 to 1400°C. The thermal expansion coefficient of the SZYG/YGZO ceramics reaches 10.9 × 10−6 K−1 (1250°C). In addition, the fracture toughness of the SZYG/YGZO ceramics increases by more than 30% compared with the SZO ceramics, and this can be attributed to the presence of the Yb0.5Zr0.5O1.75 phase.

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Arylsilanes were efficiently coupled with arylsulfinic salts for the first time under mild conditions. Diarylsulfone derivatives were easily synthesized in high yields with the assistance of nitrogen‐containing ligands and KF. The transformation is simple and efficient and the starting materials are readily available. Copyright © 2014 John Wiley & Sons, Ltd.

Strontium zirconate coating co‐doped with ytterbia and gadolinia (Sr(Zr0.9Yb0.05Gd0.05)O2.95, SZYG) and strontium zirconate coating (SrZrO3, SZ) were prepared by atmospheric plasma spraying. The SZYG coating shows improved phase stability from room temperature to 1400°C, while its thermal conductivity (~0.8 W m−1K−1) is at least ~40% lower than that of the SZ coating. Both SZYG and SZ coatings were heat‐treated at 1400°C up to 360 hours in air. The X‐ray diffraction results reveal that both the as‐sprayed SZYG and SZ coatings are composed of main phase SrZrO3 and secondary phase t‐ZrO2. These two phases do not undergo phase transition upon heat treatment up to 360 hours in the SZYG coating, whereas t‐ZrO2 transforms into m‐ZrO2 almost completely after 20 hours heat treatment in the SZ coating, suggesting a strong promoting role in stabilizing t‐ZrO2 by the additions of Yb2O3 and Gd2O3 in the SZYG coating. The content of t‐ZrO2 is ~4.3 wt.% in the as‐sprayed SZYG coating and increases to ~19.5 wt.% after 360 hours heat treatment, analyzed using Jade software. The thermal expansion coefficients (TECs) of the SZYG coatings have no abrupt decrease after heat treatment for more than 5 hours, whereas an abrupt decrease in the TECs of the SZ coating is observed after 100 hours heat treatment. The superior performance of the SZYG coating is attributed to the very stable secondary phase t‐ZrO2 stabilized by the co‐doping of ytterbia and gadolinia.

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