title: Production of nitrogen oxides by lightning and coronae discharges in simulated early Earth, Venus and Mars environments.
abstract: We present measurements for the production of nitrogen oxides (NO and N2O) in CO2-N2 mixtures that simulate different stages of the evolution of the atmospheres of the Earth, Venus and Mars. The nitrogen fixation rates by two different types of electrical discharges, namely lightning and coronae, were studied over a wide range in CO2 and N2 mixing ratios. Nitric oxide (NO) is formed with a maximum energy yield estimated to be ~1.3 x 10(16) molecule J-1 at 80% CO2 and ~1.3 x 10(14) molecule J-1 at 50% CO2 for lightning and coronae discharges, respectively. Nitrous oxide (N2O) is only formed by coronae discharge with a maximum energy yield estimated to be ~1.2 x 10(13) molecule J-1 at 50% CO2. The pronounced difference in NO production in lightning and coronae discharges and the lack of formation of N2O in lightning indicate that the physics and chemistry involved in nitrogen fixation differs substantially in these two forms of electric energy.
authors.affiliation: Laboratorio de Quimica de Plasmas y Estudios Planetarios, Instituto de Ciencias Nucleares, Universidad Nacional Autonoma de Mexico, Circuito Exterior, Cuidad Universitaria, Apartado Posatl 70-543, Mexico D.F. 04510, Mexico.
authors.forename: D
authors.initials: D
authors.lastname: Nna Mvondo
authors.forename: R
authors.initials: R
authors.lastname: Navarro-Gonzalez
authors.forename: C P
authors.initials: CP
authors.lastname: McKay
authors.forename: P
authors.initials: P
authors.lastname: Coll
authors.forename: F
authors.initials: F
authors.lastname: Raulin
mesh_terms: D001272:Atmosphere / Q000737:chemistry*; D002245:Carbon Dioxide / Q000737:chemistry*; D018534:Earth, Planet; D004560:Electricity; D019419:Evolution, Planetary; D005118:Extraterrestrial Environment / Q000737:chemistry; D008030:Lightning; D018535:Mars; D009569:Nitric Oxide / Q000138:chemical synthesis*; D009586:Nitrogen Fixation / Q000528:radiation effects*; D009609:Nitrous Oxide / Q000138:chemical synthesis*; D018536:Venus
chemical_list: D002245:Carbon Dioxide; D009569:Nitric Oxide; D009609:Nitrous Oxide