Methane 2 247 OP0UW79H66 Journal Article 2 227 Research Support, Non-U.S. Gov't 796 Sewage 541 Biofuels 485 142M471B3J 340 plus ... Carbon Dioxide 340 Air Pollutants 271 Soil 262 Anaerobic digestion 236 Manure 215 Solid Waste 159 Fatty Acids, Volatile 155 Gases 153 Water Pollutants, Chemical 141 Industrial Waste 134 7440-44-0 132 Carbon 132 Nitrogen 130 N762921K75 129 Waste Water 126 K50XQU1029 123 Nitrous Oxide 123 Oxygen 111 S88TT14065 111 methane 107 Ammonia 93 Hydrogen 92 Research Support, U.S. Gov't, Non-P.H.S. 90 moins ...