Ammonia and the Haber process. Ammonia. Ammonia (NH3) is a compound [compound: A compound is a substance formed by the chemical union (involving bond formation) of two or more elements. ] of nitrogen and hydrogen. It is a colourless gas with a choking smell, and a weak alkali which is very soluble in water.
Latent tuberculosis infection (LTBI) is a condition in which a person is infected with M. tuberculosis, but does not currently have active tuberculosis disease.
Although your body may harbor the bacteria that cause tuberculosis, your immune system usually can prevent you from becoming sick. For this reason, doctors make a distinction between: Latent TB. In this condition, you have a TB infection, but the bacteria remain in your body in an inactive state and cause no symptoms. Latent TB, also called inactive TB or TB infection, isn't contagious. It can turn into active TB, so treatment is important for the person with latent TB and to help control the spread of TB.