The intermolecular interaction determines the photophysical properties of the organic aggregates,which are critical to the performance of organic photovoltaics.Here,excitonic coupling,an important intermolecular inter...The intermolecular interaction determines the photophysical properties of the organic aggregates,which are critical to the performance of organic photovoltaics.Here,excitonic coupling,an important intermolecular interaction in organic aggregates,between theπ-stacking graphene quantum dots is studied by using transient absorption spectroscopy.We find that the spectral evolution of the ground state bleach arises from the dynamic variation of the excitonic coupling in the excitedπ-stacks.According to the spectral simulations,we demonstrate that the kinetics of the vibronic peak can be exploited as a probe to measure the dynamics of excitonic coupling in the excitedπ-stacks.展开更多
The deformation behavior of BMC, machining in difference cutting depth were investigated using SEMand cutting force measurement system. Then new fracture and shear band information extraction method based onindependen...The deformation behavior of BMC, machining in difference cutting depth were investigated using SEMand cutting force measurement system. Then new fracture and shear band information extraction method based onindependent component analysis （ICA） and fast Fourier transform （FFT） were used to analyze the original forcesignals. The main cutting force signals were extracted from the original signals by ICA method. The energy spec-trum of those main signals is processed by FFT. The analysis results show that the high frequency contents of cut-ting force increasing with the cutting depth. The fracture and shear band generation behavior in BMG chip resultin strong high frequency cutting force signals and the high frequency contents of cutting force increasing with thecutting depth. Besides, the frequency of Fz is 115 Hz and its amplitude also increases with the increasing ofdepth.展开更多
基金supported by the National Natural Science Foundation of China (No.22175145 and No.21771155)
文摘The intermolecular interaction determines the photophysical properties of the organic aggregates,which are critical to the performance of organic photovoltaics.Here,excitonic coupling,an important intermolecular interaction in organic aggregates,between theπ-stacking graphene quantum dots is studied by using transient absorption spectroscopy.We find that the spectral evolution of the ground state bleach arises from the dynamic variation of the excitonic coupling in the excitedπ-stacks.According to the spectral simulations,we demonstrate that the kinetics of the vibronic peak can be exploited as a probe to measure the dynamics of excitonic coupling in the excitedπ-stacks.
基金supported by Hubeil Natural Science Foundation,P. R. China ( No2014CFB637)
文摘The deformation behavior of BMC, machining in difference cutting depth were investigated using SEMand cutting force measurement system. Then new fracture and shear band information extraction method based onindependent component analysis （ICA） and fast Fourier transform （FFT） were used to analyze the original forcesignals. The main cutting force signals were extracted from the original signals by ICA method. The energy spec-trum of those main signals is processed by FFT. The analysis results show that the high frequency contents of cut-ting force increasing with the cutting depth. The fracture and shear band generation behavior in BMG chip resultin strong high frequency cutting force signals and the high frequency contents of cutting force increasing with thecutting depth. Besides, the frequency of Fz is 115 Hz and its amplitude also increases with the increasing ofdepth.
