Luminescent radicals have attracted extensive attention due to the unique emission properties from the doublet spin state.However,luminescent radicals are predominantly chloroarylmethyl radicals that emit light in the...Luminescent radicals have attracted extensive attention due to the unique emission properties from the doublet spin state.However,luminescent radicals are predominantly chloroarylmethyl radicals that emit light in the red and near-infrared spectral regions,and the blue emitting radicals remain scarcely reported.Herein,two novel boron-containing dioxoborocyclic blue-luminescent radicals were designed and synthesized by combining dioxoborocyclic radicals with thiophene units.They were characterized by single-crystal X-ray diffraction,UV-Vis spectroscopy,electron paramagnetic resonance(EPR)spectroscopy,and fluorescence spectroscopy in conjunction with theoretical calculations.Theoretical calculations demonstrate that both radicals 3a and 3b emit blue light from the anti-Kasha emission attributed to the effective suppression of IC pathways.Our work offers definitive proof that the boron-containing radical system functions as a highly efficient platform for expanding the diversity of short-wavelength emissive radicals.展开更多
Two new coordination compounds of rare earth chloride with N-acetyl-DL-alanine and imidazole have been prepared from absolute alcohol. The general formula RE(C5H8NO3)2(C3H5N2)2Cl3·4H2O (RE=Ce, Pr) of these compou...Two new coordination compounds of rare earth chloride with N-acetyl-DL-alanine and imidazole have been prepared from absolute alcohol. The general formula RE(C5H8NO3)2(C3H5N2)2Cl3·4H2O (RE=Ce, Pr) of these compounds were identified, by chemical and elemental analysis, FTIR spectra, UV spectra, 1H NMR and 13C NMR spectra, and molar conductance. The processes of thermal decomposition were identified by TG-DSC curves. The possible reaction mechanisms and the kinetics equation were investigated by comparing the kinetics parameters. The activation entropy of dehydration, as well as enthalpy values of dehydration and decomposition were obtained by DSC curve. The three-dimensional fluorescence spectra of liquid compounds were measured. The phenomenon of the up-conversion fluorescence is discussed.展开更多
Lanthanum oxalate hydrate La2（C2O4）3·10H2O,the precursor of La2O3 ultrafine powders,was prepared by impinging stream reactor method with PEG 20000 as surfactant.Thermal decomposition of La2（C2O4）3·10H2O ...Lanthanum oxalate hydrate La2（C2O4）3·10H2O,the precursor of La2O3 ultrafine powders,was prepared by impinging stream reactor method with PEG 20000 as surfactant.Thermal decomposition of La2（C2O4）3·10H2O from room temperature to 900 °C was investigated and intermediates and final solid products were characterized by FTIR and DSC-TG.Results show that the thermal decomposition process consists of five consecutive stage reactions.Flynn-Wall-Ozawa（FWO） and Kissinger-Akahira-Sunose（KAS） methods were implemented for the calculation of energy of activation（E）,and the results show that E depends on α,demonstrating that the decomposition reaction process of the lanthanum oxalate is of a complex kinetic mechanism.The most probable mechanistic function,G（α）=[1-（1＋α）1/3]2,and the kinetic parameters were obtained by multivariate non-linear regression analysis method.The average E-value that is compatible with the kinetic model is close to value which was obtained by FWO and KAS methods.The fitting curve matches the original TG curve very well.展开更多
基金Project supported by the National Natural Science Foundation of China(No.22231005)the Strategic Priority Research Program of the Chinese Academy of Sciences(No.XDB0610000)。
文摘Luminescent radicals have attracted extensive attention due to the unique emission properties from the doublet spin state.However,luminescent radicals are predominantly chloroarylmethyl radicals that emit light in the red and near-infrared spectral regions,and the blue emitting radicals remain scarcely reported.Herein,two novel boron-containing dioxoborocyclic blue-luminescent radicals were designed and synthesized by combining dioxoborocyclic radicals with thiophene units.They were characterized by single-crystal X-ray diffraction,UV-Vis spectroscopy,electron paramagnetic resonance(EPR)spectroscopy,and fluorescence spectroscopy in conjunction with theoretical calculations.Theoretical calculations demonstrate that both radicals 3a and 3b emit blue light from the anti-Kasha emission attributed to the effective suppression of IC pathways.Our work offers definitive proof that the boron-containing radical system functions as a highly efficient platform for expanding the diversity of short-wavelength emissive radicals.
文摘Two new coordination compounds of rare earth chloride with N-acetyl-DL-alanine and imidazole have been prepared from absolute alcohol. The general formula RE(C5H8NO3)2(C3H5N2)2Cl3·4H2O (RE=Ce, Pr) of these compounds were identified, by chemical and elemental analysis, FTIR spectra, UV spectra, 1H NMR and 13C NMR spectra, and molar conductance. The processes of thermal decomposition were identified by TG-DSC curves. The possible reaction mechanisms and the kinetics equation were investigated by comparing the kinetics parameters. The activation entropy of dehydration, as well as enthalpy values of dehydration and decomposition were obtained by DSC curve. The three-dimensional fluorescence spectra of liquid compounds were measured. The phenomenon of the up-conversion fluorescence is discussed.
基金Project (IRT0974) supported by Program for Changjiang Scholars and Innovative Research Team in University,ChinaProject (50974098) supported by the National Natural Science Foundation of China
文摘Lanthanum oxalate hydrate La2（C2O4）3·10H2O,the precursor of La2O3 ultrafine powders,was prepared by impinging stream reactor method with PEG 20000 as surfactant.Thermal decomposition of La2（C2O4）3·10H2O from room temperature to 900 °C was investigated and intermediates and final solid products were characterized by FTIR and DSC-TG.Results show that the thermal decomposition process consists of five consecutive stage reactions.Flynn-Wall-Ozawa（FWO） and Kissinger-Akahira-Sunose（KAS） methods were implemented for the calculation of energy of activation（E）,and the results show that E depends on α,demonstrating that the decomposition reaction process of the lanthanum oxalate is of a complex kinetic mechanism.The most probable mechanistic function,G（α）=[1-（1＋α）1/3]2,and the kinetic parameters were obtained by multivariate non-linear regression analysis method.The average E-value that is compatible with the kinetic model is close to value which was obtained by FWO and KAS methods.The fitting curve matches the original TG curve very well.
