Two novel Cd(Ⅱ) coordination polymers, [Cd 2(C 10H 2O 8)\5(H 2O) 6] n (1) and [Cd 4(C 6H 4O 2N) 8(H 2O) 4] n (2) (C 10H 2O 8=1,2,4,5-benzenetetracarboxyl and C 6H 4O 2N=nicotinato), were hydrothermally synthesized an...Two novel Cd(Ⅱ) coordination polymers, [Cd 2(C 10H 2O 8)\5(H 2O) 6] n (1) and [Cd 4(C 6H 4O 2N) 8(H 2O) 4] n (2) (C 10H 2O 8=1,2,4,5-benzenetetracarboxyl and C 6H 4O 2N=nicotinato), were hydrothermally synthesized and characterized by X-ray diffraction of the single-crystal and fluorescence spectra. Complex 1 crystallizes in triclinic system, space group P1 with a=0.559 62(7) nm, b=0.777 58(6) nm, c=0.969 75(10) nm, α=111.981(5)°, β=101.649(6)°, γ=98.240(5)°, and Z=1. Final R=0.024 8(wR=0.078 5). Complex 2 belongs to orthorhombic system, space group Pbca with unit cell dimensions a=1.144 94(19) nm, b=1.209 69(6) nm, c=1.740 73(8) nm and Z=8. Final R=0.018 5(wR=0.034 8). Both the two complexes are coordination polymers with a two-dimensional infinite structure, the repeat unit is [Cd 2(C 10H 2O 8)(H 2O) 6] (1) and [Cd 4(C 6H 4O 2N) 8(H 2O) 4] (2) which are bridged by the ligands of 1,2,4,5-benzenetetracarboxyl(C 10H 2O 8) and nicotinato(NA), respectively. The two polymers show strong fluorescence with λ em=433 nm(λ ex=333 nm, 1) and λ em=423 nm(λ ex=330 nm, 2) in the solid state at room temperature. The emissions observed in the polymers are tentatively assigned to the ligands fluorescence(LLCT).展开更多
A new method of constant-wavelength synchronous fluorescence spectrometry for simultaneous determination of Sudan Ⅱand Sudan Ⅲ was developed with using their fluorescence phenomenon.Only one single scan is needed fo...A new method of constant-wavelength synchronous fluorescence spectrometry for simultaneous determination of Sudan Ⅱand Sudan Ⅲ was developed with using their fluorescence phenomenon.Only one single scan is needed for effective identification and quantitative determination of the two compounds simultaneously when Δλ=60 nm is chosen.The linear ranges for Sudan Ⅱ and Sudan Ⅲ were 0—3.3 and 0—2.8 μg/mL,respectively.The detection limits for Sudan Ⅱ and Sudan Ⅲ were 14 and 11 ng/mL,respectively.By using this method,Sudan Ⅱand Ⅲ in sausage samples were determined directly with the recoveries of 83.8%—109.5%.展开更多
文摘Two novel Cd(Ⅱ) coordination polymers, [Cd 2(C 10H 2O 8)\5(H 2O) 6] n (1) and [Cd 4(C 6H 4O 2N) 8(H 2O) 4] n (2) (C 10H 2O 8=1,2,4,5-benzenetetracarboxyl and C 6H 4O 2N=nicotinato), were hydrothermally synthesized and characterized by X-ray diffraction of the single-crystal and fluorescence spectra. Complex 1 crystallizes in triclinic system, space group P1 with a=0.559 62(7) nm, b=0.777 58(6) nm, c=0.969 75(10) nm, α=111.981(5)°, β=101.649(6)°, γ=98.240(5)°, and Z=1. Final R=0.024 8(wR=0.078 5). Complex 2 belongs to orthorhombic system, space group Pbca with unit cell dimensions a=1.144 94(19) nm, b=1.209 69(6) nm, c=1.740 73(8) nm and Z=8. Final R=0.018 5(wR=0.034 8). Both the two complexes are coordination polymers with a two-dimensional infinite structure, the repeat unit is [Cd 2(C 10H 2O 8)(H 2O) 6] (1) and [Cd 4(C 6H 4O 2N) 8(H 2O) 4] (2) which are bridged by the ligands of 1,2,4,5-benzenetetracarboxyl(C 10H 2O 8) and nicotinato(NA), respectively. The two polymers show strong fluorescence with λ em=433 nm(λ ex=333 nm, 1) and λ em=423 nm(λ ex=330 nm, 2) in the solid state at room temperature. The emissions observed in the polymers are tentatively assigned to the ligands fluorescence(LLCT).
文摘A new method of constant-wavelength synchronous fluorescence spectrometry for simultaneous determination of Sudan Ⅱand Sudan Ⅲ was developed with using their fluorescence phenomenon.Only one single scan is needed for effective identification and quantitative determination of the two compounds simultaneously when Δλ=60 nm is chosen.The linear ranges for Sudan Ⅱ and Sudan Ⅲ were 0—3.3 and 0—2.8 μg/mL,respectively.The detection limits for Sudan Ⅱ and Sudan Ⅲ were 14 and 11 ng/mL,respectively.By using this method,Sudan Ⅱand Ⅲ in sausage samples were determined directly with the recoveries of 83.8%—109.5%.