Sulphur Emission Control Area traces of heavy metals, refined petroleum products containing halogen compounds, sewage sludge and sludge oil. The Marine Environment Protection Committee (MEPC) has strongly encouraged members to use the scheme to report the greenhouse gasses emissions. Those gasses include Carbon dioxide, Methane, Nitrous oxide, Hydrofluorocarbons, Perfluocarbons, and Sulfur hexafluoride. The purpose of making the guidelines on CO2 emissions is to develop a system that would be used by ships during a trial period. In 2013 new regulations described in a chapter added to the MARPOL Annex VI came into effect in order to improve "energy efficiency of international shipping. The regulations
Nitrous-oxide reductase competent unit. The Cu center can undergo a one-electron redox change and hence has a function similar to that in the well-known aa-type cytochrome "c" oxidases () where it serves to receive an electron from soluble cytochromes "c". Acetylene is the most specific inhibitor of nitrous-oxide reductase. Other inhibitors include azide anion, thiocyanate, carbon monoxide, iodide, and cyanide. Nitrous-oxide reductase In enzymology, a nitrous oxide reductase also known as nitrogen:acceptor oxidoreductase (NO-forming) is an enzyme that catalyzes the final step in bacterial denitrification, the reduction of nitrous oxide to dinitrogen. It plays a critical role in preventing release of a