Ultrafast time_resolved fluorescence experiments have been performed with core antennas CP43 and CP47 of PS Ⅱ. Their dynamic fluorescence spectra were obtained with excitation wavelength 514.5 nm. For CP43, the emiss...Ultrafast time_resolved fluorescence experiments have been performed with core antennas CP43 and CP47 of PS Ⅱ. Their dynamic fluorescence spectra were obtained with excitation wavelength 514.5 nm. For CP43, the emission spectrum was found to be from 640 to 780 nm with a peak at ~680 nm and the lifetime of fluorescence was 3.54 ns. For CP47, the emission spectrum was from 630 to 775 nm with a peak at ~691 nm and the fluorescence lifetime was 3.22 ns. The fluorescence emission efficiencies of Chl a in CP43 and CP47 were calculated to be approximately 38.3% and 40.6%, respectively. The energy transfer from β_Car to Chl a in CP43 and CP47 was discussed. The rates of energy transfer from β_Car to Chl a were measured to be about 9.6×10 11 s -1 and 1.3×10 12 s -1 and energy transfer efficiencies 47.5% and 66.5% respectively. The edge_edge distances between β_Car and Chl a in CP43 and CP47 were estimated to be ~0.110 nm and ~0.085 nm respectively.展开更多
A novel ellipsoidal helical antenna is proposed and studied in this letter. As a special in-stance,the hemispherical helical antennas are analyzed firstly,which indicates that the characteristics of a two-arm unit are...A novel ellipsoidal helical antenna is proposed and studied in this letter. As a special in-stance,the hemispherical helical antennas are analyzed firstly,which indicates that the characteristics of a two-arm unit are better than that of a single-arm unit. Based on this,the ellipsoidal helical antenna,formed by changing the axial direction’s dimension of the two-arm hemispherical helical antenna,is analyzed by the moment method with curved basic and testing function. The effects to VSWR (Voltage Standing Wave Ratio),gain,polarization and patterns by the axial direction’s dimensions are inves-tigated. The study results provide dependable gist to the choice of antenna format according to the practical requirements.展开更多
文摘Ultrafast time_resolved fluorescence experiments have been performed with core antennas CP43 and CP47 of PS Ⅱ. Their dynamic fluorescence spectra were obtained with excitation wavelength 514.5 nm. For CP43, the emission spectrum was found to be from 640 to 780 nm with a peak at ~680 nm and the lifetime of fluorescence was 3.54 ns. For CP47, the emission spectrum was from 630 to 775 nm with a peak at ~691 nm and the fluorescence lifetime was 3.22 ns. The fluorescence emission efficiencies of Chl a in CP43 and CP47 were calculated to be approximately 38.3% and 40.6%, respectively. The energy transfer from β_Car to Chl a in CP43 and CP47 was discussed. The rates of energy transfer from β_Car to Chl a were measured to be about 9.6×10 11 s -1 and 1.3×10 12 s -1 and energy transfer efficiencies 47.5% and 66.5% respectively. The edge_edge distances between β_Car and Chl a in CP43 and CP47 were estimated to be ~0.110 nm and ~0.085 nm respectively.
文摘A novel ellipsoidal helical antenna is proposed and studied in this letter. As a special in-stance,the hemispherical helical antennas are analyzed firstly,which indicates that the characteristics of a two-arm unit are better than that of a single-arm unit. Based on this,the ellipsoidal helical antenna,formed by changing the axial direction’s dimension of the two-arm hemispherical helical antenna,is analyzed by the moment method with curved basic and testing function. The effects to VSWR (Voltage Standing Wave Ratio),gain,polarization and patterns by the axial direction’s dimensions are inves-tigated. The study results provide dependable gist to the choice of antenna format according to the practical requirements.