The two-photon fluorescence properties and ultrafast responses of a hyperbranched polyyne (hb-DPP-J2) with triphenylamine as the central core, Diketo-Pyrrolo-Pyrrole as the connecting unit and electron acceptor are ...The two-photon fluorescence properties and ultrafast responses of a hyperbranched polyyne (hb-DPP-J2) with triphenylamine as the central core, Diketo-Pyrrolo-Pyrrole as the connecting unit and electron acceptor are studied. The polymer has a D-π-A-π-D conjugated structure along the extended polyyne w-bridge systems, and the effective condugated unit repeats itself in the whole hyperbranehed polymer chain. The polymer exhibits a large two-photon absorption cross section and high fluorescence quantum yields. The ultrafast dynamic results give a deep understanding of the excited energy transfer processes under excitation, and reveal a long relaxation lifetime of the intramolecular charge transfer (ICT) state.展开更多
We demonstrate the temperature-dependent fluorescence properties of Pr:LiGdF4 crystal tor the first time, to the best of our knowledge, and its blue diode pumped cw red laser at 720 nm at room temperature. The fluore...We demonstrate the temperature-dependent fluorescence properties of Pr:LiGdF4 crystal tor the first time, to the best of our knowledge, and its blue diode pumped cw red laser at 720 nm at room temperature. The fluorescence lifetime and polarized emission cross sections in the visible range are measured and calculated in a temperature range from 77K to 300 K, and the variations of the fluorescence lifetime and spectra are discovered. The reasons for these changes are explained accordingly. The output wavelength of the 720nm laser is first reported on the laser performance by using a fiber-coupled laser diode at the wavelength of 442nm as the pump source, and the maximum cw output power is about 303roW.展开更多
The effect of an anionic surfactant (sodium dodecyl sulfate, SDS) on the fluorescence properties of nucleic acid with terbium (III) is studied. Results show that ribonucleic acid (RNA) presents fluorescence reaction w...The effect of an anionic surfactant (sodium dodecyl sulfate, SDS) on the fluorescence properties of nucleic acid with terbium (III) is studied. Results show that ribonucleic acid (RNA) presents fluorescence reaction with Tb (III) directly, but deoxyribonucleic acid (DNA) presents similar fluorescence reaction only after its denaturation. In the presence of SDS, the fluorescence intensity is 4.0 times and 3.5 times greater than that of DNA and RNA without SDS.展开更多
The effect of an anionic surfactant (sodium dodecyl sulfate, SDS) on the fluorescence properties of nucleic acid with terbium (III) is studied. Results show that ribonucleic acid (RNA) presents fluorescence reaction w...The effect of an anionic surfactant (sodium dodecyl sulfate, SDS) on the fluorescence properties of nucleic acid with terbium (III) is studied. Results show that ribonucleic acid (RNA) presents fluorescence reaction with Tb (III) directly, but deoxyribonucleic acid (DNA) presents similar fluorescence reaction only after its denaturation. In the presence of SDS, the fluorescence intensity is 4.0 times and 3.5 times greater than that of DNA and RNA without SDS.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 11404048,61205154 and 11375034the Fundamental Research Funds for the Central Universities under Grant Nos 3132015233,3132013104,3132014337,3132015144 and3132015152+1 种基金the State Key Laboratory of Fine Chemicals(KF1409)the Program for Liaoning Excellent Talents in University under Grant No LJQ2014051
文摘The two-photon fluorescence properties and ultrafast responses of a hyperbranched polyyne (hb-DPP-J2) with triphenylamine as the central core, Diketo-Pyrrolo-Pyrrole as the connecting unit and electron acceptor are studied. The polymer has a D-π-A-π-D conjugated structure along the extended polyyne w-bridge systems, and the effective condugated unit repeats itself in the whole hyperbranehed polymer chain. The polymer exhibits a large two-photon absorption cross section and high fluorescence quantum yields. The ultrafast dynamic results give a deep understanding of the excited energy transfer processes under excitation, and reveal a long relaxation lifetime of the intramolecular charge transfer (ICT) state.
基金Supported by the National Natural Science Foundation of China under Grant Nos 51025210,51102156 and 51272131the Young and Middle-Aged Scientists Research Awards Fund of Shandong Province under Grant No BS2011CL024
文摘We demonstrate the temperature-dependent fluorescence properties of Pr:LiGdF4 crystal tor the first time, to the best of our knowledge, and its blue diode pumped cw red laser at 720 nm at room temperature. The fluorescence lifetime and polarized emission cross sections in the visible range are measured and calculated in a temperature range from 77K to 300 K, and the variations of the fluorescence lifetime and spectra are discovered. The reasons for these changes are explained accordingly. The output wavelength of the 720nm laser is first reported on the laser performance by using a fiber-coupled laser diode at the wavelength of 442nm as the pump source, and the maximum cw output power is about 303roW.
文摘The effect of an anionic surfactant (sodium dodecyl sulfate, SDS) on the fluorescence properties of nucleic acid with terbium (III) is studied. Results show that ribonucleic acid (RNA) presents fluorescence reaction with Tb (III) directly, but deoxyribonucleic acid (DNA) presents similar fluorescence reaction only after its denaturation. In the presence of SDS, the fluorescence intensity is 4.0 times and 3.5 times greater than that of DNA and RNA without SDS.
文摘The effect of an anionic surfactant (sodium dodecyl sulfate, SDS) on the fluorescence properties of nucleic acid with terbium (III) is studied. Results show that ribonucleic acid (RNA) presents fluorescence reaction with Tb (III) directly, but deoxyribonucleic acid (DNA) presents similar fluorescence reaction only after its denaturation. In the presence of SDS, the fluorescence intensity is 4.0 times and 3.5 times greater than that of DNA and RNA without SDS.