The thermal decomposition processes in solid state CoC2O4·2H2O have been studied in air using TG/DTA, DSC and XRD techniques. TG/DTA, DSC curves showed that the decomposition proceeded through two well-defined st...The thermal decomposition processes in solid state CoC2O4·2H2O have been studied in air using TG/DTA, DSC and XRD techniques. TG/DTA, DSC curves showed that the decomposition proceeded through two well-defined steps in air. Mass loss of the thermal decomposition of CoC2O4·2H2O was in good agreement with the theoretica1 one. XRD showed that the final product of the thermal decomposition was Co3O4. The activation energies were calculated through the ASTM E698 and Flynn-Wall-Ozawa (FWO) methods, and the possible conversion functions had been estimated through the multiple-linear regression method. The activation energies for the two steps decomposition of CoC2O4·2H2O were 140.18 kJ·mol-1 and 134.61 kJ·mol-1, respective1y.展开更多
Studies of the non-isothermal decomposition of barium2,4,6-trinitroresorecinate monohydrate,Ba(TNR)·H 2 O,were carried out by means of TG-DTA,DSC and IR.The thermal decomposition mechanism and associated ki-netic...Studies of the non-isothermal decomposition of barium2,4,6-trinitroresorecinate monohydrate,Ba(TNR)·H 2 O,were carried out by means of TG-DTA,DSC and IR.The thermal decomposition mechanism and associated ki-netics were investigated.The kinetic parameters were obtained from an analysis of the DSC curves by integral and differential methods.The most probable kinetic model function of the dehydration reaction of Ba(TNR)·H 2 O was suggested by comparison of the kinetic parameters.展开更多
The effect of dispersivity on thermodynamic and kinetic parameters of chemical reactions in nanodispersed systems is theoretically investigated. On the basis of the established theoretical dependences the new method o...The effect of dispersivity on thermodynamic and kinetic parameters of chemical reactions in nanodispersed systems is theoretically investigated. On the basis of the established theoretical dependences the new method of determination of surface thermodynamic properties of nanoparticles (surface enthalpy, surface entropy and surface energy) by thermal analysis (DTA or DSC) was developed. Three examples of calculation of surface properties of nanoparticles were presented to prove the feasibility of this method.展开更多
1 Introduction Many kinds of nanocrystalline alloys have been prepared after crystallization of the corresponding amorphous alloys and their typical compositions are Fe-M’-M'-Si-B, where M’=Cu and M'=Nb, Mo,...1 Introduction Many kinds of nanocrystalline alloys have been prepared after crystallization of the corresponding amorphous alloys and their typical compositions are Fe-M’-M'-Si-B, where M’=Cu and M'=Nb, Mo, V, Hf, Ta, etc. which are called the nanocrystalline structure formation(NSF) elements. They have become a new kind of soft magnetic alloys with excellent magnetic properties. So far, much significant progress has been achieved in展开更多
The non-isothermal decomposition of lead 2,4,6-trinitroresorcinate monohydrate, Pb(TNR)·H\-2O, was investigated by means of TG-DTA, DSC and IR. The thermal decomposition mechanism and the dissociated kinetics wer...The non-isothermal decomposition of lead 2,4,6-trinitroresorcinate monohydrate, Pb(TNR)·H\-2O, was investigated by means of TG-DTA, DSC and IR. The thermal decomposition mechanism and the dissociated kinetics were also investigated. The kinetic parameters were obtained from the analysis of the DSC curves by integral and differential methods. The most probable kinetic model function of the dehydration reaction of \{Pb(TNR)·H\-2O\} was suggested by the comparison of the kinetic parameters.展开更多
Chalcogenide films find many applications in electronics as memory device, laser writer & xerography. To tailor the property to the requirement, various compositions of Cd, Te and Se have been deposited and charac...Chalcogenide films find many applications in electronics as memory device, laser writer & xerography. To tailor the property to the requirement, various compositions of Cd, Te and Se have been deposited and characterized optically. Films have been deposited by thermal evaporation as well as by electron beam evaporation. Thermal analysis such as TGA, DTA and DSC has been carried out before deposition to ensure the composition. Dependence of Eg on the composition has been justified from (T% data) Transmittance measurements. Drastic changes in optical property due to annealing in the range 200°C to 400°C have been investigated.展开更多
文摘The thermal decomposition processes in solid state CoC2O4·2H2O have been studied in air using TG/DTA, DSC and XRD techniques. TG/DTA, DSC curves showed that the decomposition proceeded through two well-defined steps in air. Mass loss of the thermal decomposition of CoC2O4·2H2O was in good agreement with the theoretica1 one. XRD showed that the final product of the thermal decomposition was Co3O4. The activation energies were calculated through the ASTM E698 and Flynn-Wall-Ozawa (FWO) methods, and the possible conversion functions had been estimated through the multiple-linear regression method. The activation energies for the two steps decomposition of CoC2O4·2H2O were 140.18 kJ·mol-1 and 134.61 kJ·mol-1, respective1y.
文摘Studies of the non-isothermal decomposition of barium2,4,6-trinitroresorecinate monohydrate,Ba(TNR)·H 2 O,were carried out by means of TG-DTA,DSC and IR.The thermal decomposition mechanism and associated ki-netics were investigated.The kinetic parameters were obtained from an analysis of the DSC curves by integral and differential methods.The most probable kinetic model function of the dehydration reaction of Ba(TNR)·H 2 O was suggested by comparison of the kinetic parameters.
文摘The effect of dispersivity on thermodynamic and kinetic parameters of chemical reactions in nanodispersed systems is theoretically investigated. On the basis of the established theoretical dependences the new method of determination of surface thermodynamic properties of nanoparticles (surface enthalpy, surface entropy and surface energy) by thermal analysis (DTA or DSC) was developed. Three examples of calculation of surface properties of nanoparticles were presented to prove the feasibility of this method.
文摘1 Introduction Many kinds of nanocrystalline alloys have been prepared after crystallization of the corresponding amorphous alloys and their typical compositions are Fe-M’-M'-Si-B, where M’=Cu and M'=Nb, Mo, V, Hf, Ta, etc. which are called the nanocrystalline structure formation(NSF) elements. They have become a new kind of soft magnetic alloys with excellent magnetic properties. So far, much significant progress has been achieved in
基金Supported by the Science and Technology Foundation of Shaanxi Key L aboratory of Physico- Inorganic Chemistry(No.2 9- 32 0 0 1) and the Science and Technology Foundation of the National Defence Key L aboratory of Propellantand ExplosiveCom bustion
文摘The non-isothermal decomposition of lead 2,4,6-trinitroresorcinate monohydrate, Pb(TNR)·H\-2O, was investigated by means of TG-DTA, DSC and IR. The thermal decomposition mechanism and the dissociated kinetics were also investigated. The kinetic parameters were obtained from the analysis of the DSC curves by integral and differential methods. The most probable kinetic model function of the dehydration reaction of \{Pb(TNR)·H\-2O\} was suggested by the comparison of the kinetic parameters.
文摘Chalcogenide films find many applications in electronics as memory device, laser writer & xerography. To tailor the property to the requirement, various compositions of Cd, Te and Se have been deposited and characterized optically. Films have been deposited by thermal evaporation as well as by electron beam evaporation. Thermal analysis such as TGA, DTA and DSC has been carried out before deposition to ensure the composition. Dependence of Eg on the composition has been justified from (T% data) Transmittance measurements. Drastic changes in optical property due to annealing in the range 200°C to 400°C have been investigated.
