M69 incendiary M69 incendiary The M69 incendiary bomblet was used in air raids on Japan and China during World War II. They were nicknamed "Tokyo calling cards". The M69 was a plain steel pipe with a hexagonal cross section in diameter and long. It weighed about . The bomblet used napalm (jelled gasoline) as an incendiary filler, improving on earlier designs which used thermite or magnesium fillers that burned more intensely, but were less energy- and weight-efficient, and were easier to extinguish. In Germany they were filled with jellied oil and dropped in clusters of 36 in the non-aerodynamic M19 bomb. Over
Naphthenic acid Naphthenic acid Naphthenic acids (NAs) are a mixture of several cyclopentyl and cyclohexyl carboxylic acids with molecular weight of 120 to well over 700 atomic mass units. The main fraction are carboxylic acids with a carbon backbone of 9 to 20 carbons. McKee et al. claim that "naphthenic acids (NAs) are primarily cycloaliphatic carboxylic acids with 10 to 16 carbons", although acids containing up to 50 carbons have been identified in heavy petroleum. The term naphthenic acid has roots in the somewhat archaic term "naphthene" (cycloaliphatic but non-aromatic) used to classify hydrocarbons. It was originally used to describe the complex