Electromechanical carbon nanothermometers are devices that work based on the interactions and relative mo- tions of double-walled carbon nanotubes (DWCNTs). In this paper, the mechanics of carbon nanotubes (CNTs) ...Electromechanical carbon nanothermometers are devices that work based on the interactions and relative mo- tions of double-walled carbon nanotubes (DWCNTs). In this paper, the mechanics of carbon nanotubes (CNTs) con- stituting two welt-known configurations for nanothermome- ter, namely shuttle configuration and telescope configuration are fully investigated. Lennard-Jones (LJ) potential func- tion along with the continuum approximation is employed to investigate van der Waals (vdW) interactions between the in- teracting entities. Accordingly, semi-analytical expressions in terms of single integrals are obtained for vdW interactions. Acceptance condition and suction energy are studied for the shuttle configuration. In addition, a universal potential en- ergy is presented for the shuttle configuration consisting of two finite CNTs. Also, for the telescope configuration, ex- tensive studies are performed on the distributions of potential energy and interaction force for various radii and lengths of CNTs. It is found that these geometrical parameters have a considerable effect on the potential energy.展开更多
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) ...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.展开更多
文摘Electromechanical carbon nanothermometers are devices that work based on the interactions and relative mo- tions of double-walled carbon nanotubes (DWCNTs). In this paper, the mechanics of carbon nanotubes (CNTs) con- stituting two welt-known configurations for nanothermome- ter, namely shuttle configuration and telescope configuration are fully investigated. Lennard-Jones (LJ) potential func- tion along with the continuum approximation is employed to investigate van der Waals (vdW) interactions between the in- teracting entities. Accordingly, semi-analytical expressions in terms of single integrals are obtained for vdW interactions. Acceptance condition and suction energy are studied for the shuttle configuration. In addition, a universal potential en- ergy is presented for the shuttle configuration consisting of two finite CNTs. Also, for the telescope configuration, ex- tensive studies are performed on the distributions of potential energy and interaction force for various radii and lengths of CNTs. It is found that these geometrical parameters have a considerable effect on the potential energy.
基金This work was supported by National Natural Science Foundation of China (Nos. 51372265 and 21175060), the Natural Science Foundation of Jiangsu Province, China (No. BK20140392), the Open Foundation of State Key Laboratory of Materials-Oriented Chemical Engineering of Nanjing University of Technology (2014, KL14-12), the Postdoctoral Research Foundation of Jiangsu Province, China (No. 1401058B), and the Science and Technology Project of Suzhou, China (Nos~ ZXG201428 and ZXG201401)~
文摘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.