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Ammonium dinitramide (ADN) has the advantages of chlorine free, low characteristic signal and high energy compared with ammonium perchlorate (AP), which is the most likely oxidant to replace ammonium perchlorate. Therefore, we conducted theoretical calculations to analyze the influence of oxidant content and RDX content on the detonation parameters of composite explosives. We compared the detonation parameters of ADN-based composite explosives with AP-based composite explosives, then verify the theoretical calculation analysis results through actual testing. The main research conclusions of this paper are as follows: (i) The detonation parameters of ADN based composite explosive are higher than those of AP-based composite explosive, in which the detonation velocity is about 3.3%~17.2% higher, the detonation heat is about 0.65% ~41.8% higher, and the explosion volume is about 1.6% ~11.6% higher; (ii) the average detonation velocity of the ADN-based explosives tested in practice is 20.4% and 3% higher than that of AP-based explosives respectively, which is basically consistent with the theoretical calculation results. However, the work capacity is lower than that of AP-based composite explosive. [ABSTRACT FROM AUTHOR]

Abstract To understand the physiological response mechanisms of Lymantria dispar larvae to heavy metal stress, their host, 2-year-old Larix olgensis seedlings grown in pots, were treated with three different concentrations of HgCl2 (Hg). Hg accumulation and tannin content in larch needles were measured. The growth and detoxification ability of the larvae were analyzed after being fed on the Hg-stressed needles. The results showed that Hg concentration in larch needles increased with Hg treatment concentration increase, while the tannin content decreased. The larval body mass was significantly decreased. The responses of the larval antioxidant and detoxifying enzymes to Hg stress appeared to differ, with the superoxide dismutase (SOD) and peroxidase (POD) activities in 4th instar larvae were significantly higher than CK. In contrast, the acid phosphatase (ACP), alkaline phosphatase (AKP) and glutathione S-transferase (GST) activities in 4th instar larvae were significantly lower than CK. This result indicated that Hg could inhibit the growth of larvae along the food chain. The larval antioxidant and detoxification enzymes produced adaptive responses to the Hg stress, which might partially alleviate the oxidative damages caused by Hg. [ABSTRACT FROM AUTHOR]