The Meteor Event of January 17, 2004 Observed by the Swedish Infrasound Network

The improved aqueous, non-cyanide zinc electroplating solution prevents iron contamination during electroplating. The solution, in addition to water, has a copper salt, preferably copper sulfate, in a concentration of about 0.01-6% by weight of the solution, and the water-soluble reaction product of epichlorohydrin with Compound A, preferably in a concentration of about 16.67-26.67 gm./liter of solution. Compound A is a nitrogen-containing compound selected from aliphatic amine, unsubstituted heterocyclic nitrogen compound having at least two reactive nitrogen sites, and substituted heterocyclic nitrogen compound having at least two reactive nitrogen sites and 1-2 substitution groups selected from methyl, ethyl and amino groups. The reaction product, providing it includes the substituted or unsubstituted heterocyclic nitrogen compound, before use in the solution may be further reacted with a reagent of at least one of ammonia, aliphatic amine, polyamine or polyimine. A preferred reaction product is that of imidazole and epichlorohydrin in a molar ratio of about 0.7-1.7:1.