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Temperature measurement in biology and medical diagnostics, along with sensitive temperature probing in living cells, is of great importance; however, it still faces significant challenges. Metal nanoclusters （NCs） with attractive luminescent properties may be promising candidates to overcome such challenges. Here, a novel one-step synthetic method is presented to prepare highly fluorescent copper NCs （CuNCs） in ambient conditions by using glutathione （GSH） as both the reducing agent and the protective layer preventing the aggregation of the as-formed NCs. The resultant CuNCs, with an average diameter of 2.3 nm, contain 1-3 atoms and exhibit red fluorescence （A~m = 610 nm） with high quantum yields （QYs, up to 5.0%）. Interestingly, the fluorescence signal of the CuNCs is reversibly responsive to the environmental temperature in the range of 15-80 ℃. Furthermore, as the CuNCs exhibit good biocompatibility, they can pervade the MC3T3-E1 cells and enable measurements over the physiological temperature range of 15-45 ℃ with the use of the confocal fluorescence imaging method. In view of the facile synthesis method and attractive fluorescence properties, the as-prepared CuNCs may be used as photoluminescence thermometers and biosensors.

Controlled syntheses of PtNi metal nanocrystals with unique structures for catalyzing oxygen reduction reactions （ORRs） have attracted great interest. Here, we report the one-step synthesis of single-crystal PtNi octahedra with in situ-developed highly concave features and self-confined composition that are optimal for ORR. Detailed studies revealed that the Pt-rich seeding, subsequent Pt/Ni co-reduction, and Pt-Ni interfusion resulted in uniform single-crystal PtNi octahedra, and that the combination of Ni facet segregation and oxygen etching of a Ni-rich surface led to the concavity and confined Ni content. The concave PtNi nanocrystals exhibited much higher ORR performance than the commercially available Pt/C catalyst in terms of both specific activity （29.1 times higher） and mass activity （12.9 times higher） at 0.9 V （vs. reversible hydrogen electrode （RHE））. The performance was also higher than that of PtNi octahedra without concavity, confirming that the higher activity was closely related to its morphology. Moreover, the concave octahedra also exhibited remarkable stability in ORR （93% mass activity remained after 10,000 cycles between 0.6 and 1.1 V vs. RHE） owing to the passivation of the unstable sites.

The first enantioselective total synthesis of（＋）-preussin B and an improved synthesis of the antifungal alkaloid（＋）-preussin are described. Our approach relied on the four step-economical synthetic methods developed in our laboratory：（1） the cis-diastereoselective reductive dehydroxylation of hemiaminals;（2） the direct amide/lactam reductive alkylation;（3） the one-pot N,O-bisdebenzylation-N-methylation; and（4） the one-step synthesis of malimide from malic acid. Both total syntheses are quite concise, which have been achieved in six steps, and gave overall yields of 25.7% and 27.6%, respectively.

We previously isolated a natural product, namely guaiazulene-2,9-dione showing strong antibacterial activity against Vibrio anguillarum, from a gorgonian Muriceides collaris collected in South China Sea. In this experiment, guaiazulene-2,9-dione was quantitatively synthesized with an optimized one-step bromine oxidation method using guaiazulene as the raw material. The key reaction condition including reaction time and temperature, drop rate of bromine, concentration of aqueous THF solution, respective molar ratio of guaiazulene to bromine and acetic acid, and concentration of guaiazulene in aqueous THF solution, were investigated individually at five levels each for optimization. Combined with the verification test to show the absolute yield of each optimization step, the final optimal condition was determined as： when a solution of 0.025mmol mL-1 guaiazulene in 80% aqueous THF was treated with four volumes of bromine at a drop rate of 0.1 mL min 1 and four volumes of acetic acid at -5℃ for three hours, the yield of guaiazulene-2,9-dione was 23.72%. This was the first report concerning optimized one-step synthesis to provide a convenient method for the large preparation of guaiazulene-2,9-dione.

A one-step electrochemical approach for synthesis of Pt nanoparticles/reduced graphene oxide （Pt/RGO） was demonstrated. Graphene oxide （GO） and chloroplatinic acid were reduced to RGO and Pt nanoparticles （Pt NPs） simultaneously, and Pt/RGO composite was deposited on the fluorine doped SnO2 glass during the electrochemical reduction. The Pt/RGO composite was characterized by field emission-scanning electron microscopy, Raman spectroscopy and X-ray photoelectron spectroscopy, which confirmed the reduction of GO and chloroplatinic acid and the formation of Pt/RGO composite. In comparison with Pt NPs and RGO electrodes obtained by the same method, results of cyclic voltammetry and electrochemical impedance spec- troscopy measurements showed that the composite electrode had higher catalytic activity and charge transfer rate. In addition, the composite electrode had proved to have better performance in DSSCs than the Pt NPs electrode, which showed the poten- tial application in energy conversion.