Inversion of spectral information obtained during hypersonic impact

Abstract

A large number of space activities are generating a high amount of undesirable space debris, which causes inevitable damage to spacecraft and satellites. Moreover, the damage assessment of ultrahigh-speed debris is a challenging task that requires both theoretical and ground-level experimental simulations. One should note that the location and damage degree can be preliminarily determined by measuring the impact flash spectrum, which provides basic data for damage assessment. Herein, the radiation spectrum of an ultrahigh-speed collision between plastic projectile and aluminum target is measured by using spectroscopic technology. The surface temperature of the colliding material, electron temperature, and electron density in the plasma are simultaneously retrieved by using a single-frame spectrum. The single-frame spectrum is separated into a continuous spectrum and a line spectrum by using continuous thermal radiation spectrum inversion material interface temperature and line spectrum inversion electron temperature and electron density in the plasma.

Rheological Role of Stiff Nanorings on Concurrently Strengthening and Toughening Polymer Nanocomposites

“…The rheological role played by SNRs, as revealed in this study, of contributing to viscous and elastic dominance at respective high and low frequencies can be exploited to arrive at the desired dynamic mechanical properties long anticipated for a wide range of target polymeric materials. High-speed collision or friction happens frequently in reality and often results in severe damage to the participating objects. , Therefore, large toughness and strong mechanical strength are required for many related polymeric materials acting as a protective layer to dissipate the energy generated during the process of deforming at high frequencies, with the purpose of preventing the protected objects from being disrupted. Note that adding spherical NPs, nanorods, or other nano-objects like oligomers, with large surface-to-volume ratio, into polymer matrices is currently a usual way to enhance the ability of the related materials withstanding the disrupting effect of forced deformation at large strain rates.…”