A novel coordinated polymer [(C22H50N2)(Ag2I4)]n([C22H50N2]2+ = N,N?-1,2- ethylence-bis(N,N?-dimethyl octane ammonium) (EDO)) was synthesized by the reaction of AgI and EDO at room temperature with pH = 6.8, and struc...A novel coordinated polymer [(C22H50N2)(Ag2I4)]n([C22H50N2]2+ = N,N?-1,2- ethylence-bis(N,N?-dimethyl octane ammonium) (EDO)) was synthesized by the reaction of AgI and EDO at room temperature with pH = 6.8, and structurally characterized by means of X-ray single- crystal diffraction. It crystallizes in triclinic, space group P1 with a = 9.6080(1), b = 12.7643(2), c = 7.2157(8) ? a = 100.835(8), ?= 91.030(3), ? = 91.297(9)o, (C21.50H48.50Ag2I4N2), Mr = 1058.46, V = 868.71(19) 3, Z = 1, Dc = 2.023g/cm3, F(000) = 497.5, ?MoKa) = 4.692 mm-1, the final R = 0.0623 and wR = 0.1949 for 2641 observed reflections with I > 2s(I). The title compound consists of cations ([C22H50N2]2+) and anion chain (Ag2I42-)∞ which are combined by static attracting forces in the crystal to form the so-called organic-inorganic hybrid material.展开更多
The alkali halide crystals exhibit significant TL (thermoluminescence) properties when exposed to ionizing radiation. The defects in crystals can be produced in high concentration by means of chemical impurities, ra...The alkali halide crystals exhibit significant TL (thermoluminescence) properties when exposed to ionizing radiation. The defects in crystals can be produced in high concentration by means of chemical impurities, radiation, mechanical work and others processes. This study is concerned with the TL properties of quaternary mixtures of alkali halide crystals when they are irradiated with beta and gamma-rays. The samples were made mixing KCI, KBr, RbCI, RbBr salts doped with divalent europium (Eu2+), by the Czochralski method sintering at 400 ~C during 6 hours in a N2 atmosphere. The samples were exposed to beta and gamma rays. We present the TL glow curves, demonstrating that the nature of the defects in the crystals can be produced by trapping states and recombination mechanisms. The highest temperature TL curves are the most interesting due to possible applications in dosimetry and optical energy storage.展开更多
Tm^(3+) doped Na_5Lu_9F_(32) single crystal with high optical quality was grown by an improved Bridgman method. The Judd-Ofelt intensity parameters ?_t(t=2, 4, 6) were calculated according to the measured absorption s...Tm^(3+) doped Na_5Lu_9F_(32) single crystal with high optical quality was grown by an improved Bridgman method. The Judd-Ofelt intensity parameters ?_t(t=2, 4, 6) were calculated according to the measured absorption spectra and physical-chemical properties of the obtained Na_5Lu_9F_(32) single crystal. The stimulated emission cross-section of the ~3F_4→~3H_6 transition(~1.8 μm) is 0.35×10^(-20) cm^2 for Tm^(3+) doped Na_5Lu_9F_(32) single crystal. The emission spectra under the excitation of 790 nm laser diode(LD) and fluorescence lifetime at 1.8 μm were measured to reveal the fluorescence properties of Tm^(3+) doped Na_5Lu_9F_(32) single crystal. The research results show that the Tm^(3+) doped Na_5Lu_9F_(32) single crystal has larger stimulated emission cross-section compared with other crystals. All these spectral properties suggest that this kind of Tm^(3+)doped Na_5Lu_9F_(32) crystal with high physical-chemical stability and high-efficiency emission at 1.8 μm may be used as potential laser materials for optical devices.展开更多
基金This work was supported by the Foundation of Education Committee of Fujian Province (JB01020)
文摘A novel coordinated polymer [(C22H50N2)(Ag2I4)]n([C22H50N2]2+ = N,N?-1,2- ethylence-bis(N,N?-dimethyl octane ammonium) (EDO)) was synthesized by the reaction of AgI and EDO at room temperature with pH = 6.8, and structurally characterized by means of X-ray single- crystal diffraction. It crystallizes in triclinic, space group P1 with a = 9.6080(1), b = 12.7643(2), c = 7.2157(8) ? a = 100.835(8), ?= 91.030(3), ? = 91.297(9)o, (C21.50H48.50Ag2I4N2), Mr = 1058.46, V = 868.71(19) 3, Z = 1, Dc = 2.023g/cm3, F(000) = 497.5, ?MoKa) = 4.692 mm-1, the final R = 0.0623 and wR = 0.1949 for 2641 observed reflections with I > 2s(I). The title compound consists of cations ([C22H50N2]2+) and anion chain (Ag2I42-)∞ which are combined by static attracting forces in the crystal to form the so-called organic-inorganic hybrid material.
文摘The alkali halide crystals exhibit significant TL (thermoluminescence) properties when exposed to ionizing radiation. The defects in crystals can be produced in high concentration by means of chemical impurities, radiation, mechanical work and others processes. This study is concerned with the TL properties of quaternary mixtures of alkali halide crystals when they are irradiated with beta and gamma-rays. The samples were made mixing KCI, KBr, RbCI, RbBr salts doped with divalent europium (Eu2+), by the Czochralski method sintering at 400 ~C during 6 hours in a N2 atmosphere. The samples were exposed to beta and gamma rays. We present the TL glow curves, demonstrating that the nature of the defects in the crystals can be produced by trapping states and recombination mechanisms. The highest temperature TL curves are the most interesting due to possible applications in dosimetry and optical energy storage.
基金supported by the National Natural Science Foundation of China(Nos.51472125 and 51272109)the Natural Science Foundation of Zhejiang Province(No.LZ17E020001)K.C. Wong Magna Fund in Ningbo University
文摘Tm^(3+) doped Na_5Lu_9F_(32) single crystal with high optical quality was grown by an improved Bridgman method. The Judd-Ofelt intensity parameters ?_t(t=2, 4, 6) were calculated according to the measured absorption spectra and physical-chemical properties of the obtained Na_5Lu_9F_(32) single crystal. The stimulated emission cross-section of the ~3F_4→~3H_6 transition(~1.8 μm) is 0.35×10^(-20) cm^2 for Tm^(3+) doped Na_5Lu_9F_(32) single crystal. The emission spectra under the excitation of 790 nm laser diode(LD) and fluorescence lifetime at 1.8 μm were measured to reveal the fluorescence properties of Tm^(3+) doped Na_5Lu_9F_(32) single crystal. The research results show that the Tm^(3+) doped Na_5Lu_9F_(32) single crystal has larger stimulated emission cross-section compared with other crystals. All these spectral properties suggest that this kind of Tm^(3+)doped Na_5Lu_9F_(32) crystal with high physical-chemical stability and high-efficiency emission at 1.8 μm may be used as potential laser materials for optical devices.