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The significance of experimental research on flame spectra of methane-coal dust explosions is explained. Weak explosions of methane-coal dust-air mixtures were carried out in a large-scale tube of Ø 200 cm×2900cm with one end open, and the absolute radiation intensities as well as their variation under different conditions for characteristic wavelengths of 0.8875, 1.000, 1.505, 2.801, and 4.346μm were obtained by using small angle of view and a multichannel detector developed by us. The experimental results are discussed and compared with those published abroad. Based on the absolute radiation intensity measured at wavelength 4.346μm and the selected blackbody radiation model, the temperature of explosion flame was determined. The results obtained are not only of great practical importance to the industry but may also be used in the study of flame and chemical kinetics. 相似文献
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Li Yuan Sidi Huang Yinhui Hu Yuzheng Zhang Aijuan Gu Guozheng Liang Guoqiang Chen Yongming Gao Steven Nutt 《先进技术聚合物》2014,25(7):752-759
Self‐healing cyanate ester resins (CE) were developed by adding low molecular weight poly(phenylene oxide) (PPO) resin, yielding a high performance CE/PPO system via a low‐temperature process. The addition of PPO improved the flexural strength and fracture toughness of the CE matrix without sacrificing thermal properties. CE/PPO formulations with 5, 10, and 15 wt.% PPO showed 43%, 65%, and 105% increase in fracture toughness due to a combination of crack deflection, crack pinning, and matrix cavitation around second‐phase particles. When PPO was introduced into the CE, dielectric properties were either unchanged or declined. During thermal treatment to heal damaged CE, liquid PPO flowed into cracks, and during subsequent cooling, solidified to bond the crack surfaces. The self‐healing efficiency for CE with 15 wt.% PPO after heating to 220°C for 1 h exhibited a recovery of 73% in toughness and 81% in microtensile strength. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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自锁模Cr:LiSAF激光器的实验研究 总被引:2,自引:1,他引:1
以功率为900mW,波长为488nm的单线氩离子激光作为泵浦源,在腔内不加任何主动调制器和可饱和吸收体的情况下实现了Cr:LiSAF激光器的飞秒级自锁模运转,得到了脉冲宽度为40fs,重复频率为100MHz,平均输出功率为45mW的稳定的锁模脉冲序列。 相似文献
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Water swelling rubber (WSR) was prepared by reaction blending SBR andsodium polyacrylate (PAANa). The existing states of water in the WSR was studied bymeans of DSC and TG. It was found that water exists in three states: nonfreezing water,bound freezable water and free water. The relationships between water states and structureof PAANa were investigated. The results showed that the amount of non-freezing waterwas related to total water content, and the ratio of non-freezing water versus -COONagroups on PAANa (mol/mol) was about 4. However, total water content slightly affectedthe content of bound freezable water and remarkably affected the amount of free waer. 相似文献
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比较了行波与驻波两种工作方式以及前向波与返波型行波的不同特点;研究了返波型行波电子直线加速结构的工作特性;并针对返波型行波电子直线加速结构的特点,进行工作模式的选择;对工作频率为2856MHz,3π/4模的返波加速结构进行了优化设计;研究了带聚束段的返波型行波加速管的纵向与横向粒子动力学问题;为海关大型集装箱在线检测用加速器设计了一根9MeV返波型行波加速管,并与采用盘荷波导结构的加速管进行了对比.研究结果表明,返波型行波电子直线加速结构具有一定的优势,它把鼻锥型加速结构分流阻抗高及盘荷波导行波工作方式填充时间短,工作稳定性好等优点结合起来,性能明显优越. 相似文献
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顶空–气相色谱/质谱法测定餐垫纸中16种挥发性有机物残留 总被引:1,自引:0,他引:1
采用顶空–气相色谱/质谱法同时测定餐垫纸中16种挥发性有机化合物(无水乙醇、异丙醇、正丁醇、丙酮、丁酮、己醛乙酸乙酯、乙酸异丙酯、乙酸丁酯、丙二醇甲醚、乙酸正丙酯、苯、甲苯、间二甲苯、对二甲苯、邻二甲苯)的含量。采用恒流模式,流速设定为2.5 mL/min,程序升温,16种挥发性有机化合物可以很好地分离。各成分工作曲线的相关系数r2均大于0.999 5,加标回收率在86.6%~104.8%之间,测定结果的相对标准偏差均不大于6.9%(n=6);各成分的检出限均低于0.01 mg/m2。该法具有进样简单,分离效果好,精密度高等特点,能够满足餐垫纸中挥发性有机物检测要求。 相似文献
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正庚烷云雾爆轰特性的研究 总被引:2,自引:2,他引:2
本文从理论和实验上研究了正庚烷的云雾爆轰特性。实验中采用红外技术、传感器技术、烟膜技术分别测量了正庚烷云雾引爆的延迟时间tDDT,爆速D,爆压p和爆轰波阵面结构。在理论上提出了含有化学反应项的液滴燃烧模型,进行了正庚烷云雾爆轰过程的数值模拟。计算结果和实验基本符合。 相似文献