利用动态差示扫描量热(DSC)实验初步研究了硝基胍的热分解特性,采用Kissinger和Ozawa法计算了其热分解活化能。运用中断回归实验研究了热履历对硝基胍热分解安全性的影响,并用等温DSC实验进行了验证。利用绝热量热仪(ARC)研究了硝基胍...利用动态差示扫描量热(DSC)实验初步研究了硝基胍的热分解特性,采用Kissinger和Ozawa法计算了其热分解活化能。运用中断回归实验研究了热履历对硝基胍热分解安全性的影响,并用等温DSC实验进行了验证。利用绝热量热仪(ARC)研究了硝基胍的绝热安全性,得到了其初始分解温度,温升速率。结果表明,硝基胍是熔融分解型含能材料,其热分解为自催化反应。热履历显著影响了硝基胍的热分解安全性,降低了其起始分解温度和峰温,使其在固态时就达到较高的热分解速率。在动态DSC实验中,其起始反应温度213.8~249.9℃,峰温215.0~255.2℃,表观活化能为111.6 k J·mol^(-1)和114.2 k J·mol^(-1)。在绝热实验中,其起始反应温度为170.6℃,最大温升速率为1.414℃·min^(-1)。展开更多
The presence of coal dust explosions in coal mining are significant safety hazards.This study mainly explores the flame propagation of coal dust combustion so as to provide a theoretical basis for the prevention and c...The presence of coal dust explosions in coal mining are significant safety hazards.This study mainly explores the flame propagation of coal dust combustion so as to provide a theoretical basis for the prevention and control of coal dust explosions.In the experiment,a dust cloud ignition device was used to experimentally explore the influence of the coal dust concentration on the flame propagation of the coal dust,and high-speed photography was used to record the coal dust flame propagation process.The results show that the flame propagates vertically along the wall of the vertical glass tube,emits a bright yellow light during the propagation process,and forms a mushroom cloud-shaped flame at the upper end of the vertical glass tube.When the concentration of coal dust is 250 g/m^(3),its burning time is much less than those of 500 g/m^(3)and 750 g/m^(3).When the concentrations are 250 g/m^(3),500 g/m^(3)and 750 g/m^(3),respectively,the corresponding maximum propagation velocities of the flame front reach 1.51 m/s,2.00 m/s and 1.61 m/s at 100 ms,353 ms and 310 ms,respectively.The time for the flame front velocity to reach the maximum and the maximum velocity of flame propagation first increase and then decrease with the rising of concentration.展开更多
文摘利用动态差示扫描量热(DSC)实验初步研究了硝基胍的热分解特性,采用Kissinger和Ozawa法计算了其热分解活化能。运用中断回归实验研究了热履历对硝基胍热分解安全性的影响,并用等温DSC实验进行了验证。利用绝热量热仪(ARC)研究了硝基胍的绝热安全性,得到了其初始分解温度,温升速率。结果表明,硝基胍是熔融分解型含能材料,其热分解为自催化反应。热履历显著影响了硝基胍的热分解安全性,降低了其起始分解温度和峰温,使其在固态时就达到较高的热分解速率。在动态DSC实验中,其起始反应温度213.8~249.9℃,峰温215.0~255.2℃,表观活化能为111.6 k J·mol^(-1)和114.2 k J·mol^(-1)。在绝热实验中,其起始反应温度为170.6℃,最大温升速率为1.414℃·min^(-1)。
基金National Natural Science Foundation of China(No.11802272)Key Research and Development(R&D)Projects of Shanxi Province(No.201903D121028)+1 种基金Natural Science Foundation of Shanxi Province(No.201901D211228)National Defense Key Laboratory Foundation of Science and Technology on Combustion and Explosive Laboratory(Nos.6142603200509,6142603180408)。
文摘The presence of coal dust explosions in coal mining are significant safety hazards.This study mainly explores the flame propagation of coal dust combustion so as to provide a theoretical basis for the prevention and control of coal dust explosions.In the experiment,a dust cloud ignition device was used to experimentally explore the influence of the coal dust concentration on the flame propagation of the coal dust,and high-speed photography was used to record the coal dust flame propagation process.The results show that the flame propagates vertically along the wall of the vertical glass tube,emits a bright yellow light during the propagation process,and forms a mushroom cloud-shaped flame at the upper end of the vertical glass tube.When the concentration of coal dust is 250 g/m^(3),its burning time is much less than those of 500 g/m^(3)and 750 g/m^(3).When the concentrations are 250 g/m^(3),500 g/m^(3)and 750 g/m^(3),respectively,the corresponding maximum propagation velocities of the flame front reach 1.51 m/s,2.00 m/s and 1.61 m/s at 100 ms,353 ms and 310 ms,respectively.The time for the flame front velocity to reach the maximum and the maximum velocity of flame propagation first increase and then decrease with the rising of concentration.
