This study focuses on the physical and chemical properties of surficial lunar regolith (LR) samples returned from the Moon by the Chang'E-5 (CE-5) mission. Insights regarding the effect of a new sampling geological site on the surficial lunar sample CE5C0400 were illustrated using nondestructive techniques such as laser diffractometry coupled with image analysis, X-ray computed tomography, and field emission scanning electron microscopy equipped with energy dispersive spectroscopy, and Xray diffraction combined with Rietveld refinement. From the characterization analyses, the CE-5 sampling site in the northeastern Oceanus Procellarum on the Moon yields a unique collection of relatively regular-shaped and fine basalt-dominated particles. The median grain size D 50 is (55.24±0.96) μm, falling within the relatively low end of the range of the Apollo lunar returned samples. The coefficient of uniformity C u of 15.1 and the coefficient of curvature C c of 1.7 could classify CE5C0400 to be well-graded. The minerals in CE5C0400 comprise approximately 44.5% pyroxene, 30.4% plagioclase, 3.6% olivine, and 6.0% ilmenite. There is a relatively low content of approximately 15.5% glass phase in the CE-5 lunar sample. From the results, we deduce that the CE-5 LR structure could have mainly resulted from micrometeoroid impacts to achieve such a high level of maturity.

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Acrylonitrile-Butadiene-Styrene (ABS)/CaCO3 composites were reprocessed under normal conditions. The effects of reprocessing on the degradation of ABS were investigated by Fourier transform infrared spectroscopy (FTIR) and gel permeation chromatography (GPC). The mechanical properties of the reprocessed materials were measured. In this paper, a method to evaluate the degradation of ABS in ABS/CaCO3 composites by FTIR was described. The results show that within the range of the reprocessing cycles studied, as the number of reprocessing cycles increased, the impact strength of composite was significantly reduced if the content of CaCO3 is lower than 10%, due to the degradation of rubber phase. However, the impact strength was almost unchanged when the content of CaCO3 was higher than 15%.

Calcium carbonate (CaCO3) is a filler widely used in plastics. In this study, the effects of CaCO3content and size on the thermal properties of acrylonitrile-butadiene-styrene (ABS)/CaCO3composites were determined by thermogravimetric analysis (TGA) and differential scanning calorimetry (DSC). TGA results in nitrogen showed that the maximum weight loss rate of the composites gradually decreased with increasing CaCO3content. TGA results in a mixed gas containing oxygen showed that CaCO3addition facilitated the degradation of ABS, and ABS degradation was completed at relatively low temperatures. The effect of nano-CaCO3on the thermal stability of the composites was similar to that of microsized CaCO3.