冲击压缩状态下液态一氧化碳和氮混合物的发射光谱

利用二级轻气炮驱动铜飞片以2.21 km·s-1的速度撞击铝合金低温靶,产生速度为18.76 km·s-1的一维冲击波作用于等比例冷凝的一氧化碳和氮均匀混合液体样品.同时,借助增强光电耦合传感器及瞬态摄谱技术捕获到冲击压力为33.5 GPa下样品完全离解成等离子体时的线状光谱.分析这些数据可知,文章所述的六通道光谱系统能可靠地测量和记录介质的冲击压缩一发光过程;其中主要产物的发射谱线表明,一氧化碳和氮均质体已经发生了化学反应和相变.此外,与中心波长较高的谱线强度相比,488 nm通道的光谱强度明显较高的事实,也证明高密度碳氢液体在冲击压力作用下确实存在从"光学薄"到"光学厚"的转变.

Emission Spectrum of Liquid CO-N_2 Mixture at Shock Compression

Driving a copper projectile to impact a cryo-target made of aluminous alloy at the speed of 2.21 km·s-1 with a two stage light gas gun, a proper one dimensional shockwave with a speed of 18.76 km·s-1 was generated and directly acted on a uniform liquid in target, which was condensed by proportional gaseous carbon monoxide and nitrogen. At the measurement of Hugoniots, the full linear spectrum entirely dissociated with the plasma under the shock pressure of 33.5 GPa was caught by the use of intensified charge coupled device and accurate spectrographic technology. From the analysis of the spectrum, the authors know that the transient spectrograph with six channels can be used to measure and record the course of shock compression-irradiancy reliably, and the emitted spectral lines of shock compressed products indicated that the thermal dissociation and phase transition had occurred in homogeneous liquid of CO-N2. Furthermore, comparing the spectral intensity of lower central wavelength with that of higher, the fact of stronger intensity of 488 nm also validates that changes from “optic thin” to “optic thick” exist indeed in dense hydrocarbon liquid acted on by shock pressure.