Critical temperature(Tb) of thermal explosion for energetic materials is estimated from Semenov's thermal explosion theory and the non-isothermal kinetic equation da/dt=Aoexp(bT)[1+(T-T0)b][(a) deduced via r...Critical temperature(Tb) of thermal explosion for energetic materials is estimated from Semenov's thermal explosion theory and the non-isothermal kinetic equation da/dt=Aoexp(bT)[1+(T-T0)b][(a) deduced via reasonable hypotheses, where To is the initial point of the deviation from the baseline of DSC curve. The final formula is (Tb-Te0){ 1+1/[1+( Tb-T00)b]}=1. We can easily obtain the initial temperature(T0/) and onset temperature(Tci) from the non-isothermal DSC curves, the values of Too and Tc0 from the equation TOi or ei=T00 or c0+α1βi+a2βi^2+…+aL-2L-2βiL-2, i=1,2,…L, the value of b from the equation: In[β/(Tei-T0i)]=ln[A0/G(a)]+bTei, so as to calculate the value of Tb. The result obtained with this method coincides completely with the value of Tb obtained by Hu-Yang-Liang-Wu method.展开更多
The thermal behavior, nonisothermal decomposition reaction kinetics and specific heat capacity of nitrate glycerol ether cellulose(NGEC) were determined by thermogravimetric analysis(TGA), differential scanning ca...The thermal behavior, nonisothermal decomposition reaction kinetics and specific heat capacity of nitrate glycerol ether cellulose(NGEC) were determined by thermogravimetric analysis(TGA), differential scanning calori- metry(DSC) and microcalorimetry. The apparent activity energy(Ea), reaction mechanism function, quadratic equa- tion of specific heat capacity(Cp) with temperature were obtained. The kinetic parameters of the decomposition reac- tion are Ea=170.2 kJ/mol and lg(A/s^-l)=16.3. The kinetic equation isf(α)=(4/3)(1-α)[-ln(1-α)]^1/4. The specific heat capacity equation is Cp=1.285-6.276×10^-3T+1.581×10^-5T^2(283 K〈T〈353 K). With these parameters, the thermal safety properties of NGEC were studied, such as the self-accelerating decomposition temperature(TSADT), critical temperature of thermal explosion(Tb) and adiabatic time-to-explosion(tTlad). The results of the thermal safety evalua- tion of NGEC are: TSADV=459.6 K, Tb=492.8 K, tTlad=0.8 S.展开更多
Two general expressions and their six derived formulae for estimating the critical temperature(Tb) of thermal explosion for energetic materials(EMs) were derived from the Semenov's thermal explosion theory and ei...Two general expressions and their six derived formulae for estimating the critical temperature(Tb) of thermal explosion for energetic materials(EMs) were derived from the Semenov's thermal explosion theory and eight non-isothermal kinetic equations via reasonable hypothesis. We can easily obtain the values of the initial temperature(T0i) at which DSC curve deviates from the baseline of the non-isothermal DSC curve of EMs, the onset temperature(Tei), the exothermic decomposition reaction kinetic parameters and the values of Too and Te0 from the equation Toiorei=Tooore0+α1β1+α2β2+...+αL-2βi^L-2, i=1, 2, …, L and then calculate the values of Tb by means of the six derived formulae. The results obtained with the six derived calculating methods for six trinitromethyl explosives: bis(2,2,2- trinitroethyl-N-nitro) ethylene diamine(BTNEDA), 2,2,2-trinitroethyl-4,4,4-trinitrobutyrate(TNETB), bis(2,2,2- trinitroethyl) formal(BNTF), bis(2,2,2-trinitroethyl-nitramine)(BTNNA), 2,2,2-trinitroethyl-2,2,2-trinitroethyl-N- nitroamino acetate(TNTNNA) and tetrakis [2,2,2-trinitroethyl] orthoester(TTNOE) agree well with each other.展开更多
基金Supported by the National Natural Science Foundation of China (No.20573098)
文摘Critical temperature(Tb) of thermal explosion for energetic materials is estimated from Semenov's thermal explosion theory and the non-isothermal kinetic equation da/dt=Aoexp(bT)[1+(T-T0)b][(a) deduced via reasonable hypotheses, where To is the initial point of the deviation from the baseline of DSC curve. The final formula is (Tb-Te0){ 1+1/[1+( Tb-T00)b]}=1. We can easily obtain the initial temperature(T0/) and onset temperature(Tci) from the non-isothermal DSC curves, the values of Too and Tc0 from the equation TOi or ei=T00 or c0+α1βi+a2βi^2+…+aL-2L-2βiL-2, i=1,2,…L, the value of b from the equation: In[β/(Tei-T0i)]=ln[A0/G(a)]+bTei, so as to calculate the value of Tb. The result obtained with this method coincides completely with the value of Tb obtained by Hu-Yang-Liang-Wu method.
基金Supported by the Foundation of National Key Laboratory of Science and Technology on Combustion and Explosion of China(No.9140C3503011004)
文摘The thermal behavior, nonisothermal decomposition reaction kinetics and specific heat capacity of nitrate glycerol ether cellulose(NGEC) were determined by thermogravimetric analysis(TGA), differential scanning calori- metry(DSC) and microcalorimetry. The apparent activity energy(Ea), reaction mechanism function, quadratic equa- tion of specific heat capacity(Cp) with temperature were obtained. The kinetic parameters of the decomposition reac- tion are Ea=170.2 kJ/mol and lg(A/s^-l)=16.3. The kinetic equation isf(α)=(4/3)(1-α)[-ln(1-α)]^1/4. The specific heat capacity equation is Cp=1.285-6.276×10^-3T+1.581×10^-5T^2(283 K〈T〈353 K). With these parameters, the thermal safety properties of NGEC were studied, such as the self-accelerating decomposition temperature(TSADT), critical temperature of thermal explosion(Tb) and adiabatic time-to-explosion(tTlad). The results of the thermal safety evalua- tion of NGEC are: TSADV=459.6 K, Tb=492.8 K, tTlad=0.8 S.
基金Supported by the National Natural Science Foundation of China(Nos.20573098, 50846021 and 69075036)
文摘Two general expressions and their six derived formulae for estimating the critical temperature(Tb) of thermal explosion for energetic materials(EMs) were derived from the Semenov's thermal explosion theory and eight non-isothermal kinetic equations via reasonable hypothesis. We can easily obtain the values of the initial temperature(T0i) at which DSC curve deviates from the baseline of the non-isothermal DSC curve of EMs, the onset temperature(Tei), the exothermic decomposition reaction kinetic parameters and the values of Too and Te0 from the equation Toiorei=Tooore0+α1β1+α2β2+...+αL-2βi^L-2, i=1, 2, …, L and then calculate the values of Tb by means of the six derived formulae. The results obtained with the six derived calculating methods for six trinitromethyl explosives: bis(2,2,2- trinitroethyl-N-nitro) ethylene diamine(BTNEDA), 2,2,2-trinitroethyl-4,4,4-trinitrobutyrate(TNETB), bis(2,2,2- trinitroethyl) formal(BNTF), bis(2,2,2-trinitroethyl-nitramine)(BTNNA), 2,2,2-trinitroethyl-2,2,2-trinitroethyl-N- nitroamino acetate(TNTNNA) and tetrakis [2,2,2-trinitroethyl] orthoester(TTNOE) agree well with each other.