Energy transfer is ubiquitous in natural and artificial lightharvesting systems,and coherent energy transfer,a highly efficient energy transfer process,has been accepted to play a vital role in such systems.However,th...Energy transfer is ubiquitous in natural and artificial lightharvesting systems,and coherent energy transfer,a highly efficient energy transfer process,has been accepted to play a vital role in such systems.However,the energy oscillation of coherent energy transfer is exceedingly difficult to capture because of its evanescence due to the interaction with a thermal environment.Here a microscopic quantum model is used to study the time evolution of electrons triggered energy transfer between coherently coupled donoracceptor molecules in scanning tunneling microscope(STM).A series of topics in the plasmonic nanocavity(PNC)coupled donor-acceptor molecules system are discussed,including resonant and nonresonant coherent energy transfer,dephasing assisted energy transfer,PNC coupling strength dependent energy transfer,Fano resonance of coherently coupled donor-acceptor molecules,and polariton-mediated energy transfer.展开更多
In this paper, results are presented on first application of laser-induced breakdown spectroscopy (LIBS) technique for quantitative determination of Mg concentration in alpha-olefins. It is demonstrated that this te...In this paper, results are presented on first application of laser-induced breakdown spectroscopy (LIBS) technique for quantitative determination of Mg concentration in alpha-olefins. It is demonstrated that this technique gives accuracies in Mg concentrations which are comparable with those of traditional methods, as ICP-OES, in short times and without need for sample preparation. Limits of detection for Mg of the order of 500 ppb are demonstrated. Moreover, a brief discussion about the realization of orooer calibration curves and the definition of the limit of detection (LOD) is reoorted.展开更多
Some experimental investigations were carried out with the samples of metal Al and AlCl3 solutions. It is found that the spectrum varies with the change of experimental setup parameters both in Al bulk material and Al...Some experimental investigations were carried out with the samples of metal Al and AlCl3 solutions. It is found that the spectrum varies with the change of experimental setup parameters both in Al bulk material and AlCl3 solutions. The temporal evolution properties and the affection of incident laser energy on the laser-induced breakdown spectroscopy (LIBS) signals were also discussed. The lifetime of laser induced plasma in AlCl3 solutions is found to be about 30 ns which is much shorter than in solid materials. Compared with the solid samples, the Al LIBS signals in AlCl3 solutions require higher laser energy. Under the optimized conditions, the detection limit of Al in AlCl3 solution was determined to be around 1000 ppm for the system we used.展开更多
Laser-induced fluorescence excitation spectra of jet-cooled NiS molecules were recorded in the energy range of 12200-13550 cm^-1. Four vibronic bands with rotational structure have been observed and assigned to the [1...Laser-induced fluorescence excitation spectra of jet-cooled NiS molecules were recorded in the energy range of 12200-13550 cm^-1. Four vibronic bands with rotational structure have been observed and assigned to the [12.4]^3∑-0-X^3∑0 transition progression. The relevant rotational constants, significant isotopic shifts, and (equilibrium) molecular parameters have been determined. In addition, the lifetimes of the observed bands have also been measured.展开更多
基金supported by the State Scholarship Fund organized by the China Scholarship Council(CSC).
文摘Energy transfer is ubiquitous in natural and artificial lightharvesting systems,and coherent energy transfer,a highly efficient energy transfer process,has been accepted to play a vital role in such systems.However,the energy oscillation of coherent energy transfer is exceedingly difficult to capture because of its evanescence due to the interaction with a thermal environment.Here a microscopic quantum model is used to study the time evolution of electrons triggered energy transfer between coherently coupled donoracceptor molecules in scanning tunneling microscope(STM).A series of topics in the plasmonic nanocavity(PNC)coupled donor-acceptor molecules system are discussed,including resonant and nonresonant coherent energy transfer,dephasing assisted energy transfer,PNC coupling strength dependent energy transfer,Fano resonance of coherently coupled donor-acceptor molecules,and polariton-mediated energy transfer.
文摘In this paper, results are presented on first application of laser-induced breakdown spectroscopy (LIBS) technique for quantitative determination of Mg concentration in alpha-olefins. It is demonstrated that this technique gives accuracies in Mg concentrations which are comparable with those of traditional methods, as ICP-OES, in short times and without need for sample preparation. Limits of detection for Mg of the order of 500 ppb are demonstrated. Moreover, a brief discussion about the realization of orooer calibration curves and the definition of the limit of detection (LOD) is reoorted.
基金This work was supported by Hi-Tech Research and DevelopmentProgram of China (2002AA615170)Natural Science Foundationof Anhui (2001KJ116ZD)Natural Science Foundation ofShandong (Y2006A26)
文摘Some experimental investigations were carried out with the samples of metal Al and AlCl3 solutions. It is found that the spectrum varies with the change of experimental setup parameters both in Al bulk material and AlCl3 solutions. The temporal evolution properties and the affection of incident laser energy on the laser-induced breakdown spectroscopy (LIBS) signals were also discussed. The lifetime of laser induced plasma in AlCl3 solutions is found to be about 30 ns which is much shorter than in solid materials. Compared with the solid samples, the Al LIBS signals in AlCl3 solutions require higher laser energy. Under the optimized conditions, the detection limit of Al in AlCl3 solution was determined to be around 1000 ppm for the system we used.
基金This work was supported by the National Natural Science Foundation of China (No.21273212 and No.21173205), the National Key Basic Research Program of China (No.2010CB923302), the Chinese Academy of Sciences (No.KJCX2-YW-N24), the Fundamental Research Funds for the Central Universities of China (No.WK2340000012), and the University of Science and Technology of China-National Synchrotron Radiation Laboratory (No.KY2340000021).
文摘Laser-induced fluorescence excitation spectra of jet-cooled NiS molecules were recorded in the energy range of 12200-13550 cm^-1. Four vibronic bands with rotational structure have been observed and assigned to the [12.4]^3∑-0-X^3∑0 transition progression. The relevant rotational constants, significant isotopic shifts, and (equilibrium) molecular parameters have been determined. In addition, the lifetimes of the observed bands have also been measured.