No abstract

A facile, one-pot synthetic method has been proposed to prepare water-soluble fluorescent copper nanoclusters (CuNCs) templated by nucleosides. The nucleoside-templated fluorescent CuNCs were further characterized by using various analytical techniques, such as transmission electron microscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectroscopy, and fluorescence spectroscopy. The role of various reactants such as ascorbic acid, nucleoside, and citrate buffer in the synthesis process of fluorescent CuNCs was explored. The results showed that nucleoside and ascorbic acid were very likey to respectively act as a stabilizer and a reductant to form nanoclusters, and citrate buffer acted as both pH regulator solution and a reducing agent. The fluorescence spectra of various nucleoside-templated CuNCs were finally combined with multivariate chemometrics analysis for discrimination of different nucleosides.

We reported a sensitive and selective fluorescence "turn on-off" strategy for detection of Cu 2+ and hemin, respectively. The fluorescence "turn on" sensor for Cu 2+ detection had a wide linear range of 0.05-2.0 mM with a limit of detection (LOD) of 0.032 mM, and the fluorescence "turn off" sensor for hemin detection possessed a wide linear range of 0.05-4.0 mM with an LOD of 0.045 mM. The sensor for Cu 2+ or hemin exhibited high selectivity over other possible substances. In addition, it was demonstrated by using various analytical characterization techniques that the fluorescence "turn on" sensor for Cu 2+ was constructed on the basis of the formation of water-soluble fluorescent copper nanoclusters (CuNCs), and the fabrication of the fluorescence "turn off" sensor for hemin was predominately based on the inner filter effect of hemin on the fluorescence of the CuNCs. Finally, the proposed fluorescence "turn on-off" sensor system was successfully applied for detection of Cu 2+ in lake water samples and hemin in duck blood samples.

We tested the validity and reliability of the Attitudes Towards School Violence Questionnaire with Chinese high school students. We translated the questionnaire into Chinese and performed exploratory factor analysis, confirmatory factor analysis, and test–retest and internal consistency reliability tests. As for the original questionnaire, the Chinese version of the Attitudes Towards School Violence Questionnaire comprises 28 items designed to measure four attitudes toward violence: that violence is a form of fun, a way to increase selfesteem, a way to solve problems, and perceived as legitimate. There were significant positive correlations among the students' attitudes toward school violence, and both their impulsive tendency and aggressive behavior. The results show that as the Chinese version of the Attitudes Towards School Violence Questionnaire had adequate psychometric properties, it can be used to assess the attitudes of Chinese high school students toward school violence.