Ultraviolet excitation (8-ns duration) is employed to study the decomposition of RDX (1,3,5-trinitro-1,3,5-triazacyclohexane) and HMX (1,3,5,7-tetranitro-1,3,5,7-tetrazacyclooctane) from their first excited electronic states. Isolated RDX and HMX are generated in the gas phase utilizing a combination of matrix-assisted laser desorption and supersonic jet expansion techniques. The NO molecule is...

Fused deposition modeling (FDM) as one of the additive manufacturing (AM) technologies has been widely used in various industries to fabricate products with complex structures; however, application FDM energetic materials (EMs) was still less common. In this work, effect HMX solid content and particle size on viscosity molten TNT/HMX explosives were investigated. Then, computational fluid dynam...

Size reduction of high energy materials such as 1, 3, 5, 7-tetranitro- 1, 3, 5, 7-tetraaza cyclooctane (HMX) has considerable influences on improving their explosive characteristics. In this study, nanosized HMX par‌ticles were produced using ultrasonically reprecipitation method by applying water as a safe and accessible antisolvent instead of unsafe conventional methods. SEM photographs revea...

size reduction of high energy materials such as 1, 3, 5, 7-tetranitro- 1, 3, 5, 7-tetraaza cyclooctane (hmx) has considerable influences on improving their explosive characteristics. in this study, nanosized hmx par­ticles were produced using ultrasonically reprecipitation method by applying water as a safe and accessible antisolvent instead of unsafe conventional methods. sem photographs revea...

This paper describes the separation of two of the most widely used explosive compounds, RDX (1,3,5-Trinitro-1,3, 5-triazacyclohexane) and HMX (1,3,5,7-tetranitro-1,3,5,7tetraazacyclooctane). A simple antisolvent phase separation process to obtain >99% pure RDX from an explosive mixture consisting of RDX (≈90%) and HMX (≈10%) was developed. The process does not require modifications to the exist...

Thermodynamic properties of β-HMX crystal are investigated using the quasi-harmonic approximation and density functional theory within the local density approximation (LDA), generalized gradient approximation (GGA), and GGA + empirical van der Waals (vdW) correction. It is found that GGA well describes the thermal expansion coefficient and heat capacity but fails to produce correct bulk modulus...

Abstract In this paper, confined explosions of HMX-based thermobaric explosives in a spherical chamber were studied. The effects 1, 1-diamino-2, 2-dinitroethene (FOX-7) on the explosion performances and afterburning obtained by changing its content. results showed that composition (HMX/FOX-7) enhanced total impulse, but effect improving initial energy quasi-static pressure (QSP) was slight. alu...

BACKGROUND The defect structure of organic materials is important as it plays a major role in their crystal growth properties. It also can play a subcritical role in "hot-spot" detonation processes of energetics and one such energetic is cyclotetramethylene-tetranitramine, in the commonly used beta form (β-HMX). RESULTS The as-grown crystals grown by evaporation from acetone show prismatic, t...

Despite extensive efforts on studying the decomposition mechanism of HMX under extreme condition, an intrinsic understanding of mechanical and chemical response processes, inducing the initial chemical reaction, is not yet achieved. In this work, the microscopic dynamic response and initial decomposition of β-HMX with (1 0 0) surface and molecular vacancy under shock condition, were explored by...

The molecular architecture of developing serotonin (5HT) neurons is poorly understood, yet its determination is likely to be essential for elucidating functional heterogeneity of these cells and the contribution of serotonergic dysfunction to disease pathogenesis. Here, we describe the purification of postmitotic embryonic 5HT neurons by flow cytometry for whole-genome microarray expression pro...