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This study aimed to explore the effect of ultrasound-assisted pH shift on the structural and functional properties of soybean lipophilic proteins (SLP). SLP were modified under ultrasound (240 W, 20 min) and extreme pH (pH 1 or 12) conditions. The primary, secondary and tertiary structures of native and modified SLP were characterized by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE), free sulfhydryl content, Fourier transform infrared (FTIR) spectroscopy, and fluorescence spectroscopy, and their functional properties were analyzed. The results showed that ultrasound-assisted alkaline pH shift resulted in the greatest changes in the structural and functional properties of SLP. The average particle size of SLP decreased from 5 245.33 to 447.13 nm, the ζ-potential value decreased from − 5.95 to − 18.53 mV, the free sulfhydryl content decreased, the α-helix content increased, and the fluorescence spectrum exhibited a blue shift and a decrease in fluorescence intensity. In addition, the solubility increased from 9.84% to 92.04%, and the emulsifying and foaming properties increased. Therefore, ultrasound and pH shift treatments have a synergistic effect on the structural and functional properties of SLP, and they are closely correlated with each other.

ε-CL-20 is currently the most powerful commercially available explosive, but its high mechanical sensitivity and low phase stability limit its broad applications. In order to reduce the sensitivity of ε-CL-20, cross-linked graphene oxide (GO), using triaminoguanidine–glyoxal polymer (TAGP) as the bridging agent, was prepared in the ε-CL-20 solution, which could constrain the nano-sized ε-CL-20 crystals following a conventional solvent–nonsolvent in situ crystallization method. It was shown that the polymorphic transition temperature of the assembled CL-20/GO–TAGP crystals increased by about 36.0 °C at a maximum level compared with pristine ε-CL-20, and the polymorphic transformation temperature varied depending on the content of the cross-linked GO. Moreover, the heats of formation for the resulting modified products such as CL-20-2 (950.0 kJ kg−1) and CL-20-4 (848.3 kJ kg−1) were 26.9% and 13.3% higher than that of pure ε-CL-20 (748.9 kJ kg−1), respectively. The measured density of assembled CL-20 crystals was almost unchanged as 2.01 g cm−3 under a certain condition. The impact and friction sensitivities of the modified samples, such as CL-20-1, CL-20-3, and CL-20-6, were obviously reduced. More importantly, two of the assembled products even showed a certain improvement in specific impulse and detonation performance. [ABSTRACT FROM AUTHOR]

• ECs can enhance the combustion of Si/Ta. • Core-shell structure has some advantages compared with traditional mechanical mixing preparation method. • The reaction mechanism for ECs enhanced Si/Ta combustion was summarized. • Heat release efficiency of the composites could be well tuned by using different content and type of the ECs. This paper reports a group of new energetic materials (EMs) based on Si/Ta coated with recently developed high energetic composites (ECs), such as AP/NC and PVDF/CL-20. These Si/Ta-based nano-energetic composites have been prepared by both mechanical mixing method and an advanced technique of electrostatic self-assembly followed with a spray-drying process. The heat of reaction and combustion behavior of these novel Si/Ta@ECs composites, as well as the morphologies and compositions of their condensed combustion products (CCPs) have been comprehensively studied. It has been shown that the combustion efficiency of Si-Ta could be largely enhanced with the inclusion of two types of ECs. The maximum energy release was 18.39 kJ cm−3 of Si/Ta with the inclusion of ECs prepared by electrostatic self-assembly followed with spray-drying technique, which was 51.6% of the theoretical energy density of the pure Si/Ta and it is about 9.58 kJ cm−3 higher than the mechanically mixed one. It shows that the enhanced flame has improved luminosity and radiation due to increased energy content with higher reaction rate. The maximum flame-front propagation rate and the condensed phase reaction rate of Si/Ta with the addition of 10 wt% of ECs are 30.1 mm s−1 and 120.7 mg s−1, respectively. The maximum combustion wave temperature of Si/Ta-based composite was 2.4 times higher than that of pure Si/Ta without the ECs inclusion. The typical phase composition of the CCPs is composed of TaSi 2 , which is combined with a minor inclusion of Ta 2 O 5 , TaN 0.25 , TaC and Ta 5 Si 3. The two-step reaction mechanism includes the activation and propagation of the fast combustion wave of the ECs and the initiation of the post-burning reaction. [ABSTRACT FROM AUTHOR]