It is for this reason that is referred to as a complementary DNA or cDNA. Though there are numerous processes for synthesizing cDNA, the best way of doing so is by using mature or fully spliced mRNA. This is usually done by using the enzyme reverse transcriptase.
Ammonia is used as refrigerant prominently in the refrigeration systems of food industry like dairies, ice creams plants, frozen food production plants, cold storage warehouses, processors of fish, poultry and meat and number of other applications.
Unlike ammonia, urea is safe and easy to handle. The products, ammonia and carbon dioxide, together with the exhaust gases, are passed immediately over a catalyst in the exhaust system. Ammonia reduces the oxides of nitrogen (mainly nitric oxide), formed in the combustion processes, to nitrogen.