EuFeO_3 was prepared by the complexation method of citric acid. The Perovskite phase of EuFeO_3 was determined by XRD. The redox mechanism for oxidation of CO on EuFeO_3 was proven by the pulse method of reduction wit...EuFeO_3 was prepared by the complexation method of citric acid. The Perovskite phase of EuFeO_3 was determined by XRD. The redox mechanism for oxidation of CO on EuFeO_3 was proven by the pulse method of reduction with CO and reoxidation with O_2. The redox kinetics of oxidation for CO on EuFeO_3 has been investigated with the external circulation flow reactor. The experimental data obeyed the redox equation. The parameters of the kinetic equation were estimated by the method of orthogonal design.展开更多
Kinetics and mechanism of oxidation induced contraction of MgAl2O4 spinel carbon composites reinforced by Al4C3 in situ reaction were researched in air using vertical high temperature thermal dilatometer from 25℃to 1...Kinetics and mechanism of oxidation induced contraction of MgAl2O4 spinel carbon composites reinforced by Al4C3 in situ reaction were researched in air using vertical high temperature thermal dilatometer from 25℃to 1400℃.It is shown that oxidation induced contraction of MgAl2O4 spinel carbon composites reinforced Al4C3 in situ reaction is the common logarithm of oxidation time t and the oxygen partial pressure P inside MgAl2O4 spinel carbon composites reinforced by Al4C3 in situ reaction in air at 1400℃is as follows:P=F(-2.75×10^-4A+2.13×10^-3)lnt.The nonsteady diffusion kinetic equation of O2 at 1400℃inside the composites is as follows:J=De lnt.Acceleration of the total diffusional?flux of oxygen inside the composites at 1400℃is in inverse proportion to the oxidation time.The nonsteady state effective diffusion coefficient De of O2(g)inside the composites decreases in direct proportional to the increase of the amount of metallic aluminium.The method of preventing the oxidation induced contraction of MgAl2O4 spinel carbon composites reinforced by Al4C3 in situ reaction is to increase the amount of Al.The slag erosion index of MgO-Al2O3 spinel carbon composite reinforced by Al4C3 in situ reaction is 0.47 times that of MgO-CaO brick used in the lining above slag line area of a VOD stainless steel-making vessel.HMOR of MgO-Al2O3 spinel carbon composite reinforced by Al4C3 in situ reaction is 26.7 MPa,HMOR of the composite is 3.6 times the same as that of MgO-CaO brick used in the lining above slag line area of a VOD vessel.Its service life is two times as many as that of MgO-CaO brick.展开更多
The thermal decomposition behavior and kinetic parameters of the exothermic decomposition reactions of the title compound in a temperature-programmed mode have been investigated by means of DSC, TG-DTG and lower rate ...The thermal decomposition behavior and kinetic parameters of the exothermic decomposition reactions of the title compound in a temperature-programmed mode have been investigated by means of DSC, TG-DTG and lower rate thermolysis/FTIR. The possible reaction mechanism was proposed. The critical temperature of thermal explo-sion was calculated. The influence of the title compound on the combustion characteristic of composite modified double base propellant containing RDX has been explored with the strand burner. The results show that the kinetic model function in differential form, apparent activation energy Ea and pre-exponential factor A of the major exo-thermic decomposition reaction are 1-a, 207.98 kJmol-1 and 1015.64 s-1, respectively. The critical temperature of thermal explosion of the compound is 312.87 ℃. The kinetic equation of the major exothermic decomposition process of the title compound at 0.1 MPa could be expressed as: ()416.422.502?d101 edTTaa-10=-. As an auxiliary catalyst, the title compound can help the main catalyst lead salt of 4-hydroxy-3,5-dinitropyridine oxide to en-hance the burning rate and reduce the pressure exponent of RDX-CMDB propellant.展开更多
文摘EuFeO_3 was prepared by the complexation method of citric acid. The Perovskite phase of EuFeO_3 was determined by XRD. The redox mechanism for oxidation of CO on EuFeO_3 was proven by the pulse method of reduction with CO and reoxidation with O_2. The redox kinetics of oxidation for CO on EuFeO_3 has been investigated with the external circulation flow reactor. The experimental data obeyed the redox equation. The parameters of the kinetic equation were estimated by the method of orthogonal design.
基金Funded by the National Torch Plan of China(No.2005EB031110)the National Scientific and Technique Program of Ninth-five Year Plan(96-22-01-19)。
文摘Kinetics and mechanism of oxidation induced contraction of MgAl2O4 spinel carbon composites reinforced by Al4C3 in situ reaction were researched in air using vertical high temperature thermal dilatometer from 25℃to 1400℃.It is shown that oxidation induced contraction of MgAl2O4 spinel carbon composites reinforced Al4C3 in situ reaction is the common logarithm of oxidation time t and the oxygen partial pressure P inside MgAl2O4 spinel carbon composites reinforced by Al4C3 in situ reaction in air at 1400℃is as follows:P=F(-2.75×10^-4A+2.13×10^-3)lnt.The nonsteady diffusion kinetic equation of O2 at 1400℃inside the composites is as follows:J=De lnt.Acceleration of the total diffusional?flux of oxygen inside the composites at 1400℃is in inverse proportion to the oxidation time.The nonsteady state effective diffusion coefficient De of O2(g)inside the composites decreases in direct proportional to the increase of the amount of metallic aluminium.The method of preventing the oxidation induced contraction of MgAl2O4 spinel carbon composites reinforced by Al4C3 in situ reaction is to increase the amount of Al.The slag erosion index of MgO-Al2O3 spinel carbon composite reinforced by Al4C3 in situ reaction is 0.47 times that of MgO-CaO brick used in the lining above slag line area of a VOD stainless steel-making vessel.HMOR of MgO-Al2O3 spinel carbon composite reinforced by Al4C3 in situ reaction is 26.7 MPa,HMOR of the composite is 3.6 times the same as that of MgO-CaO brick used in the lining above slag line area of a VOD vessel.Its service life is two times as many as that of MgO-CaO brick.
基金the National Defense Industry Foundation (No. BZJ030901) and the Science and Technology Foundation of the National De-fense Key Laboratory of Propellant and Explosive Combustion of China (No. 51455010).
文摘The thermal decomposition behavior and kinetic parameters of the exothermic decomposition reactions of the title compound in a temperature-programmed mode have been investigated by means of DSC, TG-DTG and lower rate thermolysis/FTIR. The possible reaction mechanism was proposed. The critical temperature of thermal explo-sion was calculated. The influence of the title compound on the combustion characteristic of composite modified double base propellant containing RDX has been explored with the strand burner. The results show that the kinetic model function in differential form, apparent activation energy Ea and pre-exponential factor A of the major exo-thermic decomposition reaction are 1-a, 207.98 kJmol-1 and 1015.64 s-1, respectively. The critical temperature of thermal explosion of the compound is 312.87 ℃. The kinetic equation of the major exothermic decomposition process of the title compound at 0.1 MPa could be expressed as: ()416.422.502?d101 edTTaa-10=-. As an auxiliary catalyst, the title compound can help the main catalyst lead salt of 4-hydroxy-3,5-dinitropyridine oxide to en-hance the burning rate and reduce the pressure exponent of RDX-CMDB propellant.
