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The distance over which a normal shock motion passes is generally considered to be negatively correlated with the rising rate of backpressure; however, our experiments show that distance is independent of the rising rate of backpressure for oblique shock trains. Single-pulse backpressure was constructed to decouple the amplitude and the rising rate of backpressure and remove its cumulative effects for the first time at Ma = 1.95. Unlike normal shock, when backpressure begins to fall, the shock train does not immediately retreat but rather moves upstream to the terminal position. The mixing region may play an important role in this dynamic process. [ABSTRACT FROM AUTHOR]

Passive icephobic surfaces have been extensively studied by researchers due to their advantages of delaying icing time and reducing ice adhesion strength. However, icephobic materials with petroleum‐based resources and toxic fluorine‐containing chemicals, as one of the excellent icephobic materials, are very unfavorable for resource conservation and environmental protection. In this study, we report fluorine‐free, highly transparent, chemically durable and low ice adhesion icephobic coatings prepared by glycerol triglycidyl ether (GTE) derived from natural glycerin and bis(3‐aminopropyl) terminated polydimethylsiloxane (PDMS) via one‐pot method. On the one hand, PDMS with multiple methyl groups and two amine groups acts as a hydrophobic modifier to modulate the surface energy of the coatings, and also acts as a structure modifier to modulate the mechanical properties of the coatings, which allow us to design and synthesis the coating with excellent deicing performance (ice adhesion strength can reach about 16 kPa). On the other hand, GTE with multiple epoxy groups works as cross‐linker to endow the coatings with good cross‐linked networks, so that the coatings showed good durability after being subjected to different temperature treatment and different solution treatments. In additional, the transmittance of the coating is above 91.4%, which is expected to be applied to windows and sensors. [ABSTRACT FROM AUTHOR]

Despite tremendous advancements in icephobic coating technology, icephobic efficacy frequently declines or completely disappears in low temperatures, high humidity, and dynamic environments. Here, a hyperbranched vanillin‐based composite coating with efficient icephobic properties (HVIC) is prepared by combining vanillin‐based phosphazene compounds with oil‐stored SiO2 through imine bonds‐ HVIC exhibits excellent hydrophobicity, with a water sliding angle of 9°. This coating's exceptional slippery performance imparts outstanding non‐adhesive, self‐cleaning characteristics, and deicing properties (τice: 8.2 kPa). It is noteworthy that HVIC performs exceptional anti‐icing and anti‐frosting in low‐temperature and high humidity environments. Compared with superhydrophobic coatings (SHC), the icing delay time of HVIC is 9.1 times that of SHC, and the frosting time is extended by roughly 300%. Most importantly, the HVIC‐treated propeller experienced two ice‐shedding events during the 200s dynamic icing test, while SHC completely lost its icephobic performance. This excellent dynamic icephobic performance can ensure the normal operation of the equipment while reducing energy consumption. The HVIC also exhibits significant UV shielding, antibacterial, flame retardant, self‐healing, and recyclability properties. The HVIC is regarded as having significant potential for application due to its easy and scalable approach. [ABSTRACT FROM AUTHOR]