Unsymmetrical dimethylhydrazine (UDMH) (1,1-Dimethylhydrazine) is a hypergolicrocket fuel[?] ingredient, often used in combination with the oxidiser, nitrogen tetroxide.
UDMH is toxic, and can explode in the presence of oxidisers.
... abbreviation for Deutsche Bahn, the major German railway company
DB is the abbreviation of Dominion Breweries[?], a major beer brewing company of New Zealand.
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