Mesoamerican ballgame many Caribbean islands including Cuba, Puerto Rico, and the West Indies, has been proposed as a descendent of the Mesoamerican ballgame, perhaps through the Maya. Mesoamerican ballgame The Mesoamerican ballgame was a sport with ritual associations played since 1400 BC by the pre-Columbian people of Ancient Mesoamerica. The sport had different versions in different places during the millennia, and a newer more modern version of the game, "ulama", is still played in a few places by the indigenous population. The rules of the game are not known, but judging from its descendant, ulama, they were probably similar to racquetball, where
Nitrogen fixation protons and a strong reducing agent rather than with H itself. In 2011, yet another molybdenum-based system was discovered, but with a diphosphorus pincer ligand. Photolytic nitrogen splitting is also considered. Nitrogen fixation at a p-block element was published in 2018 whereby one molecule of dinitrogen is bound by two transient Lewis-base-stabilized borylene species. The resulting dianion was subsequently oxidized to a neutral compound, and reduced using water. Nitrogen fixation Nitrogen fixation is a process by which nitrogen in the Earth's atmosphere is converted into ammonia (NH) or related nitrogenous compounds. Atmospheric nitrogen, which is molecular dinitrogen (N), is relatively