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Explosive terrorism characteristics of explosives and explosions
Published in Robert A. Burke, Counter-Terrorism for Emergency Responders, 2017
Hydrazoic acid or hydrogen azide is a dangerous explosion risk when shocked or heated. Metal fulminates, such as mercury fulminate, explode readily when dry. It is used in the manufacturing of caps and detonators for producing explosions. Ammonium chlorate, which is shock sensitive, can detonate when exposed to heat or vibration. It is used in the production of explosives. Ammonium perchlorate is also shock sensitive and may explode when exposed to heat or by spontaneous chemical reaction. This is the material that was involved in the explosion at the Pepcon plant in Henderson, Nevada. It is used in the production of explosives, pyrotechnics, etching, engraving, and jet and rocket propellants. Diethylene glycol dinitrate is a severe explosion hazard when shocked or heated. It is used as a plasticizer in solid rocket propellants.
Nuclear Fuel Recycling
Published in Kenneth D. Kok, Nuclear Engineering Handbook, 2016
Patricia Paviet, Michael F. Simpson
Hydrazoic acid is an unstable compound: the pure chemical form can be exploded when heated or shocked. Its relatively low boiling point (T = 35.7 °C under atmospheric pressure) makes it volatile at room temperature, which has considerable impact on safety. Scientists at the Savannah River Site investigated the hazards of hydrazoic acid in connection with the use of hydrazine as a holding reductant and uranous nitrate as the partitioning reagent (Horner, 1969). In their study, they showed that hydrazoic acid never reached the critical explosive concentration (4.7 M in the aqueous solution) in their process because dilute solutions (<0.2 M) of hydrazine were used. By analogy, there was no hazard associated with the use of ferrous nitrate—hydrazine solutions because the maximum hydrazine concentration was 0.2 M. However, the extraction of hydrazoic acid into the organic phase may result in the formation of sodium azide in the alkaline-solvent wash solutions which use sodium bicarbonate to recycle TBP. Thus, it was recommended to destroy hydrazoic acid by treatment with sodium nitrite before being discharged into waste tanks.
A facile approach of tetraaqua-bis[4-(H-tetrazol-5-yl)pyridinato]-zinc(II) dihydrate with their biological activities
Published in Journal of Coordination Chemistry, 2023
Rama Devi Gutta, Abdul Rajack, Satya Veni Sunkara
The conventional synthesis of 5-substituted-1H-tetrazoles is [3 + 2] cycloaddition reaction of metal azide or hydrazoic acid with the nitrile (cyanide group) [9], which has several drawbacks, such as the use of highly toxic metal azide, explosive nitriles, strong Lewis acid, and hydrazoic acid [10]. This procedure is further improved with the "click" chemistry approach utilizing zinc salts as catalysts in an aqueous solution but still requires the removal of zinc salts from the acidic products, which is a time-consuming and tedious process [11]. Later Xue et al. reported coordination polymers by hydrothermal method using 4-cyanopyridine, CdCl2, and sodium azide [12]. This gave a pathway for many pyridine tetrazole metal complexes to synthesize in situ by the hydro/solvothermal method [13]. However, the hydrothermal method involves the reaction time to be completed ranging from 24 to 86 h [14]. This reaction was further fine-tuned by the development of several synthetic strategies and methodologies, including the use of inorganic salts and metal complexes in stoichiometric amounts [15] as catalysts, the use of metal salts under solvent-free conditions in micellar media and ionic liquids, and the use of Lewis acids, various catalysts [16].