The hazardous compounds are: two forms of hydrazine, nitrogen tetroxide and a pure form of ammonia.

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Indeed, the data are only in opposition to making fuel from algae if nitrogen and phosphorus nutrients are added in their mineral forms, and if the CO2 has to be injected into the system, as produced elsewhere and transported as a compressed gas.

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All life forms on earth use six elements: oxygen, carbon, hydrogen, nitrogen, phosphorus and sulfur.

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