The thermal decomposition of the strontium chloride hexahydrate and its kinetics were studied under non isothermal condition in nitrogen by thermogravimetric and derivative thermogravimetric techniques. The intermedi...The thermal decomposition of the strontium chloride hexahydrate and its kinetics were studied under non isothermal condition in nitrogen by thermogravimetric and derivative thermogravimetric techniques. The intermediate and residue for each decomposition were identified from TG curve. The non isothermal kinetic data were analyzed by the Achar method and the Coats Redfern method. The possible reaction mechanisms were suggested by comparing the kinetic parameters. The kinetic equation for the first stage can be expressed as d α /d t = A exp(- E/RT)(1-α ), the second stage, d α /d t = A exp(- E/RT)3(1-α ) 2/3 , and the third stage, d α /d t = A exp(- E/RT)3/2(1-α ) 2/3 [1-(1- α ) 1/3 ] -1 . Mathematic expressions of the kinetic compensation effects of each stage of the thermal decomposition reaction were also obtained.展开更多
a, a'-Bis(substituted benzylidene)cycloalkanones were efficiently prepared from cycloalkanones and benzaldehydes in [bmim][BF4] by using iron(III) chloride hexahydrate as a catalyst. It is shown that [bmim][BF4] a...a, a'-Bis(substituted benzylidene)cycloalkanones were efficiently prepared from cycloalkanones and benzaldehydes in [bmim][BF4] by using iron(III) chloride hexahydrate as a catalyst. It is shown that [bmim][BF4] and iron(III) chloride hexahydrate can be quantitatively recovered and be reused effectively for many times. Compared with the known methods, this novel process has the advantage of being an envkonmentally benign process together with good yields and mild reaction conditions.展开更多
A ternary complex [Sm(o-NBA)3phen]2 (o-NBA: o-Nitrobenzoate; phen: 1,10-phenanthroline) was synthesized and characterized by elemental analysis, IR, molar conductance, and thermogravimetric analysis. The dissolution e...A ternary complex [Sm(o-NBA)3phen]2 (o-NBA: o-Nitrobenzoate; phen: 1,10-phenanthroline) was synthesized and characterized by elemental analysis, IR, molar conductance, and thermogravimetric analysis. The dissolution enthalpies of SmCl3·6H2O(s), o-HNBA(s) and phen·H2O(s) in mixed solvent (VHCl :VDMF :VDMSO=2:2:1) were determined by calorimetry at 298.15 K. The enthalpy change of the reaction was determined to be rHmΔ θ=252.49±1.60 kJ/mol. Using the relevant data in the literature and a thermochemical recycle...展开更多
[Sm(C7H5O3)2(C4H6NO2S)]·2H2O was synthesized from the reaction of samarium chloride hexahydrate with salicylic acid and thioproline,and characterized by IR,elemental analysis and thermogravimatric analysis.Th...[Sm(C7H5O3)2(C4H6NO2S)]·2H2O was synthesized from the reaction of samarium chloride hexahydrate with salicylic acid and thioproline,and characterized by IR,elemental analysis and thermogravimatric analysis.The standard molar enthalpies of the solutions of SmCl3·6H2O(s),2[C7H6O3(s)],[C4H7NO2S(s)] and [Sm(C7H5O3)2·(C4H6NO2S)·2H2O(s)] in a mixed solvent of absolute ethyl alcohol,dimethyl formamide(DMF) and 3 mol/L HCl were,respectively,determined by calorimetry to be ΔsHm^Θ [SmCl3·6H2O(s),298.15 K]=(-46.68±0.15) kJ/mol,ΔsHm^Θ [2C7H6O3(s),298.15 K]=(25.19±0.02) kJ/mol,ΔsHm^Θ [C4H7NO2S(s),298.15 K]=(16.20±0.17) kJ/mol and ΔsHm^Θ {[Sm(C7H5O3)2(C4H6NO2S)]·2H2O(s),298.15 K}=(-81.24±0.67) kJ/mol.The enthalpy change of the reaction SmCl3·6H2O(s)+2C7H6O3(s)+C4H7NO2S(s)=[Sm(C7H5O3)2(C4H6NO2S)]·2H2O(s)+3HCl(g)+4H2O(l) was determined to be ΔrHm^Θ =(123.45±0.71) kJ/mol.From the data in the literature,the standard molar formation enthalpy of [Sm(C7H5O3)2(C4H6NO2S)]·2H2O(s) was estimated to be Δf Hm^Θ {[Sm(C7H5O3)2(C4H6NO2S)]·2H2O(s),298.15 K}=(-2912.03±3.1) kJ/mol through Hess' law.展开更多
In the presence of metallic samariumcobalt (II) chloride hexahydrate, the nitrones can be reduced to the corresponding imines in moderate to high yields under mild and neutral conditions.
The reaction of Zn(ClO4)2·6H2O with 3,3'-bis(2-benzimidazolyl)-2,2'-dipyridine (L) gave a mononuclear zinc(Ⅱ) complex: [ZnL2](CIO4)2·2DMF·4H2O, which was structurally characterized by EA, ...The reaction of Zn(ClO4)2·6H2O with 3,3'-bis(2-benzimidazolyl)-2,2'-dipyridine (L) gave a mononuclear zinc(Ⅱ) complex: [ZnL2](CIO4)2·2DMF·4H2O, which was structurally characterized by EA, IR, UV, ^1H NMR, fluorescence spectrum and single-crystal X-ray diffraction. The crystal (C54H54Cl2N14O14Zn, Mr = 1259.38) belongs to the monoclinic system, space group C2/c with a = 20.874(2), b = 14.9953(16), c = 20.462(3)A,β= 101.553(2)°, V= 6274.8(13) A, Z= 4, Dc= 1.333 g/cm^3, F (000) = 2608,/a(MoKcr) = 0.548 mm 1, R = 0.0682 and wR = 0.1931 for 4984 observed reflections with I 〉 2σ(I). The Zn(Ⅱ) is four-coordinated in a slightly distorted tetrahedral geometry through four N atoms from four benzimidazole units of two ligands. In the crystal lattice, the [ZnL2]2^+ cations are linked to each other by extensive intermolecular hydrogen bonds between nitrogen atoms of benzimidazole rings, water and DMF molecules.展开更多
文摘The thermal decomposition of the strontium chloride hexahydrate and its kinetics were studied under non isothermal condition in nitrogen by thermogravimetric and derivative thermogravimetric techniques. The intermediate and residue for each decomposition were identified from TG curve. The non isothermal kinetic data were analyzed by the Achar method and the Coats Redfern method. The possible reaction mechanisms were suggested by comparing the kinetic parameters. The kinetic equation for the first stage can be expressed as d α /d t = A exp(- E/RT)(1-α ), the second stage, d α /d t = A exp(- E/RT)3(1-α ) 2/3 , and the third stage, d α /d t = A exp(- E/RT)3/2(1-α ) 2/3 [1-(1- α ) 1/3 ] -1 . Mathematic expressions of the kinetic compensation effects of each stage of the thermal decomposition reaction were also obtained.
基金supported by the National Natural Science Foundation of China under grant No.20273109.
文摘a, a'-Bis(substituted benzylidene)cycloalkanones were efficiently prepared from cycloalkanones and benzaldehydes in [bmim][BF4] by using iron(III) chloride hexahydrate as a catalyst. It is shown that [bmim][BF4] and iron(III) chloride hexahydrate can be quantitatively recovered and be reused effectively for many times. Compared with the known methods, this novel process has the advantage of being an envkonmentally benign process together with good yields and mild reaction conditions.
基金supported by the National Natural Sciences Foundation of China (20773034)the Natural Science Foundation of Hebei Province (B2007000237)
文摘A ternary complex [Sm(o-NBA)3phen]2 (o-NBA: o-Nitrobenzoate; phen: 1,10-phenanthroline) was synthesized and characterized by elemental analysis, IR, molar conductance, and thermogravimetric analysis. The dissolution enthalpies of SmCl3·6H2O(s), o-HNBA(s) and phen·H2O(s) in mixed solvent (VHCl :VDMF :VDMSO=2:2:1) were determined by calorimetry at 298.15 K. The enthalpy change of the reaction was determined to be rHmΔ θ=252.49±1.60 kJ/mol. Using the relevant data in the literature and a thermochemical recycle...
基金Supported by the Hunan Provincial Educational Ministry Foundation(No.04C635)the Hunan Provincial Natural Sciences Foundation of China(No.08JJ3014)
文摘[Sm(C7H5O3)2(C4H6NO2S)]·2H2O was synthesized from the reaction of samarium chloride hexahydrate with salicylic acid and thioproline,and characterized by IR,elemental analysis and thermogravimatric analysis.The standard molar enthalpies of the solutions of SmCl3·6H2O(s),2[C7H6O3(s)],[C4H7NO2S(s)] and [Sm(C7H5O3)2·(C4H6NO2S)·2H2O(s)] in a mixed solvent of absolute ethyl alcohol,dimethyl formamide(DMF) and 3 mol/L HCl were,respectively,determined by calorimetry to be ΔsHm^Θ [SmCl3·6H2O(s),298.15 K]=(-46.68±0.15) kJ/mol,ΔsHm^Θ [2C7H6O3(s),298.15 K]=(25.19±0.02) kJ/mol,ΔsHm^Θ [C4H7NO2S(s),298.15 K]=(16.20±0.17) kJ/mol and ΔsHm^Θ {[Sm(C7H5O3)2(C4H6NO2S)]·2H2O(s),298.15 K}=(-81.24±0.67) kJ/mol.The enthalpy change of the reaction SmCl3·6H2O(s)+2C7H6O3(s)+C4H7NO2S(s)=[Sm(C7H5O3)2(C4H6NO2S)]·2H2O(s)+3HCl(g)+4H2O(l) was determined to be ΔrHm^Θ =(123.45±0.71) kJ/mol.From the data in the literature,the standard molar formation enthalpy of [Sm(C7H5O3)2(C4H6NO2S)]·2H2O(s) was estimated to be Δf Hm^Θ {[Sm(C7H5O3)2(C4H6NO2S)]·2H2O(s),298.15 K}=(-2912.03±3.1) kJ/mol through Hess' law.
文摘In the presence of metallic samariumcobalt (II) chloride hexahydrate, the nitrones can be reduced to the corresponding imines in moderate to high yields under mild and neutral conditions.
基金Supported by the National Natural Science Foundation of China (No. 20471054) the Henan Innovation Project for University Prominent Research Talents (No. 2005 KYCX021)
文摘The reaction of Zn(ClO4)2·6H2O with 3,3'-bis(2-benzimidazolyl)-2,2'-dipyridine (L) gave a mononuclear zinc(Ⅱ) complex: [ZnL2](CIO4)2·2DMF·4H2O, which was structurally characterized by EA, IR, UV, ^1H NMR, fluorescence spectrum and single-crystal X-ray diffraction. The crystal (C54H54Cl2N14O14Zn, Mr = 1259.38) belongs to the monoclinic system, space group C2/c with a = 20.874(2), b = 14.9953(16), c = 20.462(3)A,β= 101.553(2)°, V= 6274.8(13) A, Z= 4, Dc= 1.333 g/cm^3, F (000) = 2608,/a(MoKcr) = 0.548 mm 1, R = 0.0682 and wR = 0.1931 for 4984 observed reflections with I 〉 2σ(I). The Zn(Ⅱ) is four-coordinated in a slightly distorted tetrahedral geometry through four N atoms from four benzimidazole units of two ligands. In the crystal lattice, the [ZnL2]2^+ cations are linked to each other by extensive intermolecular hydrogen bonds between nitrogen atoms of benzimidazole rings, water and DMF molecules.