Novel Experimental Simulations of the Atmospheric Injection of Meteoric Metals
Novel Experimental Simulations of the Atmospheric Injection of Meteoric Metals
复制标题
大气中金属注入的新实验模拟
DOI：
10.3847/1538-4357/aa5c8f
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发表时间：
2017
期刊：
影响因子：
--
通讯作者：
J. Plane
中科院分区：
文献类型：
--
作者：
J. C. Gómez Martín;D. Bones;J. Carrillo;A. James;J. Trigo‐Rodríguez;B. Fegley, Jr.;J. Plane
一个新开发的实验室，大气烧蚀模拟器（MASI），被用来测试模型预测星际尘埃粒子（IDPs）的大气烧蚀实验Na， Fe和Ca汽化谱。MASI是第一个能够通过精确电阻加热和原子激光诱导荧光探测进行时间分辨大气烧蚀模拟的实验室装置。利用陨石IDP类似物进行的实验表明，至少需要三种矿物相（富钠斜长石、金属硫化物和富镁硅酸盐）来解释所观察到的汽化元素的外观温度。与硅酸盐颗粒相比，富钠斜长石和金属硫化物的熔融温度较低，这妨碍了在一次熔体中所有元素成分的平衡。不同矿物组分的相变过程决定了Na和Fe的蒸发方式。钙的蒸发取决于颗粒大小和熔融硅酸盐的初始组成。测量的Na， Fe和Ca的汽化分数作为粒度和速度的函数证实了差异烧蚀（即，最易挥发的元素如Na首先烧蚀，其次是主要成分Fe， Mg和Si，最后是最难烧蚀的元素如Ca）。化学烧蚀模型（CABMOD）基于熔融硅酸盐在热力学平衡下的化学分馏提供了一个合理的近似，尽管IDPs的成分和几何描述过于简单。为了更好地再现元素烧蚀剖面的特定形状，需要对模型进行改进。
A newly developed laboratory, Meteoric Ablation Simulator (MASI), is used to test model predictions of the atmospheric ablation of interplanetary dust particles (IDPs) with experimental Na, Fe, and Ca vaporization profiles. MASI is the first laboratory setup capable of performing time-resolved atmospheric ablation simulations, by means of precision resistive heating and atomic laser-induced fluorescence detection. Experiments using meteoritic IDP analogues show that at least three mineral phases (Na-rich plagioclase, metal sulfide, and Mg-rich silicate) are required to explain the observed appearance temperatures of the vaporized elements. Low melting temperatures of Na-rich plagioclase and metal sulfide, compared to silicate grains, preclude equilibration of all the elemental constituents in a single melt. The phase-change process of distinct mineral components determines the way in which Na and Fe evaporate. Ca evaporation is dependent on particle size and on the initial composition of the molten silicate. Measured vaporized fractions of Na, Fe, and Ca as a function of particle size and speed confirm differential ablation (i.e., the most volatile elements such as Na ablate first, followed by the main constituents Fe, Mg, and Si, and finally the most refractory elements such as Ca). The Chemical Ablation Model (CABMOD) provides a reasonable approximation to this effect based on chemical fractionation of a molten silicate in thermodynamic equilibrium, even though the compositional and geometric description of IDPs is simplistic. Improvements in the model are required in order to better reproduce the specific shape of the elemental ablation profiles.
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影响因子：
5
作者：
R. Court;M. Sephton
通讯作者：
R. Court;M. Sephton
影响因子：
5.2
作者：
D. Janches;L. Dyrud;S. Broadley;J. Plane
通讯作者：
D. Janches;L. Dyrud;S. Broadley;J. Plane
影响因子：
5
作者：
R. Court;M. Sephton
通讯作者：
R. Court;M. Sephton
流星烧蚀的化学模型
影响因子：
6.3
作者：
Vondrak T
通讯作者：
Vondrak T