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In this paper, we analyze the light variation of KIC 8840638 using high-precision time-series data from the Kepler mission. The analysis reveals that this target is a new detached eclipsing binary system with a δ Scuti component, rather than a single δ Scuti star as previously known. The frequency analysis of short-cadence data reveals 95 significant frequencies, most of which lie in a frequency range of 23−32 day−1. Among them, seven independent frequencies are detected in the typical frequency range of δ Scuti stars, and they are identified as pressure modes. In addition, a possible large separation value of Δ ν = 36.5 ± 0.1 μ Hz is also detected with the Fourier transform (FT) and autocorrelation function (AC) analysis. The orbital frequency f orb (= 0.320008 day−1) and its harmonics are also detected directly in the frequency spectrum. The binary modelings derived from PHOEBE indicate that this binary system is in detached configurations with a mass ratio of q = 0.33 − 0.04 + 0.06 , an inclination angle of 40.19 − 2.84 + 3.96 ​​​​​°. The derived parameters and binary evolutionary model suggest that the primary star is an object on the verge of leaving the main sequence with a temperature of ∼7600 K, while the secondary appears to be a cool component entering the giant branch with a temperature ∼3100 K lower than the primary. Moreover, this system may have undergone a mass ratio reversal, where the more massive star is the gainer component and the less massive one is the donor star. [ABSTRACT FROM AUTHOR]

Understanding the mechanical response characteristics and determining the optimized process conditions is critical to mitigate crystal impacts during resonant acoustic mixing (RAM). Therefore, high‐melting explosive (HMX) crystal collisions with container walls under different RAM accelerations were investigated through simulations and experiments. The HMX crystal damages after RAM were assessed using microscopic imaging, small‐angle X‐ray scattering, and Brunauer–Emmett–Teller tests. Results show that crystal fractures observed in steel containers can be prevented by using low‐modulus polytetrafluoroethylene containers. Rough containers reduce internal damage but increase surface abrasion. Lower RAM accelerations, shorter RAM durations, and low‐modulus containers can mitigate HMX crystal damage. [ABSTRACT FROM AUTHOR]