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Abstract: Single-crystal SrAl2O4:Eu2+,Dy3+ nanosheets were first synthesized by a reliable two-step method. More specifically, nanosheets bundles precursors were synthesized by a facile but efficient hydrothermal route in the absence of any organic additives, catalysts, and templates, and then SrAl2O4:Eu2+,Dy3+ nanosheets were obtained by thermally splitting the precursors. The products were characterized by multiple techniques including X-ray diffraction (XRD), field-emission scanning electron microscopy (FE-SEM), and high-resolution transmission electron microscopy (HRTEM). It was found that urea was very efficient to form nanosheets bundles precursors. The as-obtained SrAl2O4:Eu2+,Dy3+ nanosheets showed higher photoluminescence intensity (at 516nm), compared with commercial corresponding powders. Furthermore, the SrAl2O4:Eu2+,Dy3+ nanosheets could sustain visible greenish-yellow light in dark places more than 16h, suggesting potential applications in many fields. [Copyright &y& Elsevier]

The treatment of high salinity wastewater is complex with high cost and energy consumption. Interfacial solar vapor generation technology because of its green, high efficiency and low energy consumption has become a hot spot in the field of water resource recovery and utilization. In this study, a novel three-dimensional porous graphene composite material (3D h-CN/r-GO) was designed by a hydrothermal reaction with fibrous carbon nitrogen (h-CN) modified graphene (r-GO), and its performance for adsorption of nitrobenzene and phenol as simulated contaminants via photothermal evaporation was studied. The results showed that 3D h-CN/r-GO has a broad-spectrum absorption and multistage channel structure and presents the characteristics of fast thermal response. Its light steam conversion efficiency can reach 90.4% under the condition of simulated sunlight. The adsorption of nitrobenzene, phenol, and other common volatile pollutants can be realized in the process of treatment, and its adsorption capacities of nitrobenzene and phenol were 67.6 mg·g -1 and 57.5 mg·g -1 , respectively. Moreover, 3D h-CN/r-GO can realize efficient interfacial solar vapor generation with long-time stability, and its retention rate of pollutants and salts is up to 98%. The recovery and utilization of steam condensate meets the discharge standard. Therefore, this study provides a promising way for the treatment of high salinity wastewater with low energy consumption and cost.

This paper reports the results of a four-part questionnaire survey to assess the effects of the sound of dental equipment on people's perceptions and dental anxiety levels. The convenience sample for the survey comprised 230 dental students and 230 gender and age matched non-dental university students. The subjects were requested to complete the questionnaires themselves. The results show that the sound of dental equipment has a great influence on dental anxiety. Dental students, who are more familiar with the operation of this equipment, are less prone to anxiety when they hear its sound than their non-dental counterparts.

Three-dimensional (3D) architectures of YBO(3)/Eu(3+) with different morphologies such as nest-like, rose-like, cruller-like, and flower-like, were hydrothermally synthesized by simply adjusting the ratios of surfactant polyethylene glycol-6000 (PEG-6000) to octadecylamine (ODA). These 3D architectures were all self-assembled by nanoflakes. X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, field emission scanning electron microscopy (FE-SEM), and photoluminescence (PL) spectra were used to characterize the morphology and structures of the samples. PEG-6000, ODA, and the ODA/PEG ratio played important roles in the formation process of various architectures. Rose-like architecture was chosen as a candidate, and the formation mechanism of the architecture was proposed on the basis of XRD analysis and SEM observation of the products at different reaction periods of time. As-synthesized samples displayed strong emission located at 591, 610, and 615 nm. Water contact angle measurements indicated that the films fabricated by the samples obtained under the different ratios of PEG-6000/ODA could exhibit tunable wettability ranging from superhydrophilicity to superhydrophobicity. This kind of one-pot bisurfactant-controlled hydrothermal synthesis method reported here provides a new strategy to realize the surfaces of functional materials with tunable wettability.