A new Pb（II）-based coordination polymer, [Pb（L）]n （1）, was hydrothermally synthesized and its structure was determined by single-crystal X-ray diffraction （H2L = octane- 1,8-dicarboxylic acid）. Compound 1 crys...A new Pb（II）-based coordination polymer, [Pb（L）]n （1）, was hydrothermally synthesized and its structure was determined by single-crystal X-ray diffraction （H2L = octane- 1,8-dicarboxylic acid）. Compound 1 crystallizes in orthorhombic, space group Pnma with a = 32.061（4）, b = 7.2597（8）, c = 4.8084（5） A, V= 1119.2（2） A3, Z = 4, C10H1604Pb, Mr = 407.42, Dc = 2.418 g/cm3, F（000） = 760, μ（MoKa） = 15.066 mm-1, R = 0.0270 and wR = 0.0666. In 1, each Pb（II） cation is coordinated by six carboxylate oxygen atoms from four L2- anions. Each L2- anion bridges three Pb（ll） atoms in a μ3：η2：η1：η1 mode to form a 3D framework. The structure of 1 was characterized by IR spectrum and thermogravimetric analysis. Moreover, solid state luminescent property of 1 was also investigated.展开更多
Recently,azobenzene-4,4'-dicarboxylic acid(ADCA)has been produced gradually for use as an organic synthesis or pharmaceutical intermediate due to its eminent performance.With large quantities put into application ...Recently,azobenzene-4,4'-dicarboxylic acid(ADCA)has been produced gradually for use as an organic synthesis or pharmaceutical intermediate due to its eminent performance.With large quantities put into application in the future,the thermal stability of this substance during storage,transportation,and use will become quite important.Thus,in this work,the thermal decomposition behavior,thermal decomposition kinetics,and thermal hazard of ADCA were investigated.Experiments were conducted by using a SENSYS evo DSC device.A combination of differential iso-conversion method,compensation parameter method,and nonlinear fitting evaluation were also used to analyze thermal kinetics and mechanism of ADCA decomposition.The results show that when conversion rate α increases,the activation energies of ADCA's first and main decomposition peaks fall.The amount of heat released during decomposition varies between 182.46 and 231.16 J·g^(-1).The proposed kinetic equation is based on the Avrami-Erofeev model,which is consistent with the decomposition progress.Applying the Frank-Kamenetskii model,a calculated self-accelerating decomposition temperature of 287.0℃is obtained.展开更多
基金Supported by the Institute Foundation of Siping City(No.2013036)
文摘A new Pb（II）-based coordination polymer, [Pb（L）]n （1）, was hydrothermally synthesized and its structure was determined by single-crystal X-ray diffraction （H2L = octane- 1,8-dicarboxylic acid）. Compound 1 crystallizes in orthorhombic, space group Pnma with a = 32.061（4）, b = 7.2597（8）, c = 4.8084（5） A, V= 1119.2（2） A3, Z = 4, C10H1604Pb, Mr = 407.42, Dc = 2.418 g/cm3, F（000） = 760, μ（MoKa） = 15.066 mm-1, R = 0.0270 and wR = 0.0666. In 1, each Pb（II） cation is coordinated by six carboxylate oxygen atoms from four L2- anions. Each L2- anion bridges three Pb（ll） atoms in a μ3：η2：η1：η1 mode to form a 3D framework. The structure of 1 was characterized by IR spectrum and thermogravimetric analysis. Moreover, solid state luminescent property of 1 was also investigated.
基金supported by National Natural Science Foundation of China(51974166).
文摘Recently,azobenzene-4,4'-dicarboxylic acid(ADCA)has been produced gradually for use as an organic synthesis or pharmaceutical intermediate due to its eminent performance.With large quantities put into application in the future,the thermal stability of this substance during storage,transportation,and use will become quite important.Thus,in this work,the thermal decomposition behavior,thermal decomposition kinetics,and thermal hazard of ADCA were investigated.Experiments were conducted by using a SENSYS evo DSC device.A combination of differential iso-conversion method,compensation parameter method,and nonlinear fitting evaluation were also used to analyze thermal kinetics and mechanism of ADCA decomposition.The results show that when conversion rate α increases,the activation energies of ADCA's first and main decomposition peaks fall.The amount of heat released during decomposition varies between 182.46 and 231.16 J·g^(-1).The proposed kinetic equation is based on the Avrami-Erofeev model,which is consistent with the decomposition progress.Applying the Frank-Kamenetskii model,a calculated self-accelerating decomposition temperature of 287.0℃is obtained.
