One hydrogen atom pairs with other free hydrogen atoms to create hydrogen gas, which is also captured and sold.

FORBES: Magazine Article

President BUSH: We will increase our research in better batteries for hybrid and electric cars and in pollution-free cars that run on hydrogen.

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So by building up the concentration of ammonium ions inside its retaining membrane, H. pylori is able to fend off the destructive attentions of the hydrogen ions in stomach acid and thus live free from competition by less hardy germs.

ECONOMIST: Stomach turning | The