Basic research of shock reaction on organic materials and its implication for cosmochemistry

为了研究多环芳烃(PAHs)的抗冲击行为，对PAHs进行了冲击实验。我们应用这些结果估计了碳质小行星在早期地球吸积阶段有机质输送相对于其撞击压力的生存程度。估算表明，导致生命的大量生前有机物质应该是由小行星运送到地球早期的。对多环芳烃进行了冲击回收实验。在实验中，我们研究了多环芳烃和δD阀的冲击波诱导脱氢，并讨论了在其形成过程中提供给地球大气和内部的氢气量。然后，我们证明了当时地球内部氢气的累积量及其δD值与已经确定的地球内部氢量相当。对墨奇森陨石样品进行了冲击恢复实验。随着脱氢反应的进行，震荡型Murchison的δD值从+10.6%0增加到+59.1%0，然后下降到-87.6%0。δ^&lt；13&gt；C的行为从-15%0下降到-7.65%0。沿着去挥发作用收集的这些同位素数据的曲线图显示了一条变化曲线，表明了这些同位素在陨石中的演化。激波是有效控制太阳系同位素特征的过程之一，我们对从墨尔奇逊陨石中提纯的不溶有机物进行了激波恢复实验。这一打击有选择地将D和13；C从国际移民组织释放出来。从IOM中选择性释放较重的同位素是由于其结构，其中D和~(13)C以不均匀形式存在，并与主网络连接较弱。这种D的有效释放可能是冲击的内在结果。因此，激波将有效地控制太阳星云演化过程中地外有机质的氢同位素行为。

Polycyclic aromatic hydrocarbons (PAHs) were impacted to study the behavior of PAHs against shock. We applied these results to estimate the survival degree of organic matter delivery by carbonaceous asteroids against their impacts pressures at the accretion stage of early Earth. The estimation suggests that a large quantity of prebiotic organic materials leading to life should have been delivered to the early Earth by the asteroids.Shock recovery experiments on PAHs were carried out. In the experiments, we examined the shock-induced dehydrogenation of PAHs and δD vales and discussed the hydrogen amounts supplied to the Earth's atmosphere and interior during its formation. Then, we show that the cumulative amount of hydrogen in the Earth's interior at that point and its δD value were comparable to those already established for the Earth's interior.Shock recovery experiments on Murchison meteorite samples were performed. δD values of the shocked Murchison showed an initial increase from +10.6%0 to +59.1%0 before declining to-87.6%0, as the dehydrogenation progressed. The behavior of δ^<13>C simply decreased from-15%0 to-7.65%0. The plot of those isotope data collected along devolatilization shows a variation curve that suggests the evolution of those isotopes in the meteorites. Shock is one of the processes effectively controlling the isotope features of the solar system.We performed shock-recovery experiments on insoluble organic matter (IOM) purified from the Murchison meteorite. The shock selectively released D and ^<13>C from the IOM. The selective release of heavier isotopes from IOM would be due to its structure, in which D and ^<13>C-enriched parts are present as an inhomogeneity and are weakly attached to the main network. This effective release of D is probably an inherent result of shock. Thus, shock would effectively control the hydrogen isotope behavior of extraterrestrial organic matter during the evolution of the solar nebula.