Results 201 to 210 of about 27,351 (240)
Some of the next articles are maybe not open access.
Nitrogen isotopes in the solar system
Geochimica et Cosmochimica Acta, 1982Measurements of the isotopic composition of nitrogen in the solar system are summarized. We show that the 30% change, during the last 3 to 4 billion years, of 15N14N in solar-wind-bearing lunar soils and breccias probably does not reflect changes in this ratio at the solar surface.
Johannes Geiss, Peter Bochsler
openaire +1 more source
Nitrogen Isotopes in Palaeolimnology
2002Nitrogen is a small but essential constituent of all organisms and as such can be regarded as a key nutrient. Together with phosphorous and silicon, it is commonly viewed as one of the nutrients that ultimately limit organic productivity. Indeed, in many lakes, N is probably the limiting nutrient.
openaire +1 more source
Geochimica et Cosmochimica Acta, 2013
Abstract The 15 N/ 14 N isotopic ratio of marine particulate organic matter usually increases as a consequence of preferential 14 N-remineralization (ammonification) during decay in the oxic water-column and at the oxic seafloor. However, a fractionation factor 15 e of sediment ammonification in natural environments has not been determined yet ...
openaire +1 more source
Abstract The 15 N/ 14 N isotopic ratio of marine particulate organic matter usually increases as a consequence of preferential 14 N-remineralization (ammonification) during decay in the oxic water-column and at the oxic seafloor. However, a fractionation factor 15 e of sediment ammonification in natural environments has not been determined yet ...
openaire +1 more source