Abstract: A pulse-echo technique, based on ultrasonic "long-bar" mode (LBM) velocity measurements, working up to 1700°C is described. Magnetostrictive transducers and ultrasonic lines used in a 40-85 kHz frequency range are detailed. The conditions of choice of fundamental parameters (frequency, line geometry, sample size) are discussed in relation with the nature and the microstructure of ...

We present a combined quantum-chemical and Monte Carlo approach for calculating exciton transport properties in disordered organic materials starting from the molecular scale. We show that traps and energetic disorder are the main limitations for exciton diffusion in conjugated polymers. An analytical model for exciton hopping in a medium of sites with uncorellated energetic disorder gives a qu...

The synthesis of 3-amino-1-nitroguanidine (3-ANQ) and 5-hydrazino tetrazole (5-HT) derivatives as new energetic materials are described. Reaction of 3-ANQ with triethyl orthoformate leads to the formation of 3-nitramino triazole while no reaction was observed whit 5-HT. Addition of NaN3 to a mixture of 3-ANQ and triethyl orthoformate, afforded 1-nitroguanidyl tetrazole in excelle...

purpose: to evaluate the effect of fullerene on chemical properties of naphazoline drug in   water by density functional theory (dft) methods.   materials and methods: naphazoline belongs to the imidazoline class of sympathomimetics.   the present study on naphazoline drug and its fullerene connected form were carried out using   computerized calculations of gaussian program in b3lyp/6-31g leve...

This work seeks to explore the macroscale, thermomechanical response of polymer-bonded composite energetic materials in their inert form high-frequency mechanical excitation range 1–100 kHz. Cylindrical samples were fabricated according a mock PBXN-109 formulation, consisting hydroxyl-terminated polybutadiene, RDX material (sucrose), and varying ratios spherical aluminum powder. Experiments per...