All articles starting with M
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Methane fermentation
Methane fermentation is anaerobic digestion in which communities of microorganisms break down manure, sewage sludge, and food waste into biogas, a methane-rich fuel mixture typically containing 55–65% methane.
Methane functionalization
Methane functionalization is the direct chemical conversion of methane into value-added products such as methanol and acetic acid by activating its C–H bonds, bypassing synthesis gas; no industrial direct process exists yet.
Methane monooxygenase
Methane monooxygenase (MMO) is the enzyme used by methanotrophic bacteria to oxidize methane to methanol, working at ambient conditions and existing as soluble iron-based sMMO and membrane-bound copper-based pMMO.
Methane on Mars
Methane on Mars refers to trace methane gas reported in the Martian atmosphere since 2004, from Curiosity and Mars Express, whose origins, geological or biological, remain debated.
Methane oxidation
Methane oxidation is the conversion of methane to oxidized products like methanol or carbon dioxide, by industrial catalysts, plasma, and methanotrophic microbes, a key climate mitigation lever.
Methane partial oxidation
Methane partial oxidation is a catalytic chemistry process converting methane with limited oxygen into methanol, formaldehyde, or syngas; direct methane-to-methanol conversion remains unindustrialized after a century of research.
Methane pyrolysis
Methane pyrolysis, also called methane decomposition or methane cracking, is a process splitting methane into hydrogen and solid carbon without CO2, yielding turquoise hydrogen at temperatures of 800 to 1600 °C.
Methane storage
Methane storage is the containment of methane, the main component of natural gas, at densities high enough for practical transport and use, most often as a vehicle fuel.
Methane to methanol
Methane to methanol (MTM) conversion turns methane into methanol, a liquid fuel and feedstock far easier to transport than methane, but selective direct conversion remains difficult.
Methane to methanol over copper zeolites
Methane to methanol over copper zeolites is the direct, selective partial oxidation of methane to methanol by copper ions in zeolites, run stepwise or in continuous flow near 200 °C.
Methane-to-methanol conversion
Methane-to-methanol conversion is the chemical transformation of methane, the main component of natural gas, into methanol, done industrially via syngas while direct routes remain a research goal.
MethaneSAT
MethaneSAT is an Earth-observing satellite spectrometer launched in March 2024 by the Environmental Defense Fund to quantify methane emissions from oil and gas basins worldwide.
Methanethiol
Methanethiol (CH3SH), also called methyl mercaptan, is the simplest thiol, a colorless, highly flammable gas smelling of rotten cabbage, detectable at about one part per billion.
Methanex
Methanex Corporation is a Vancouver-based chemical company and the world's largest methanol producer, operating plants in the United States, Chile, Trinidad and Tobago, New Zealand, Egypt, and Canada.
Methanobacteriaceae
Methanobacteriaceae, family of methane-producing archaea in the order Methanobacteriales (phylum Methanobacteriota); type genus Methanobacterium; includes Methanobrevibacter and Methanosphaera gut methanogens and digester Methanobacterium.
Methanobacteriati
Methanobacteriati (formerly Euryarchaeota) is a validly published kingdom of Archaea, named by Göker and Oren in 2024 with type genus Methanobacterium, containing the classical methanogens and the phylum Methanobacteriota.
Methanobrevibacter smithii
Methanobrevibacter smithii (Balch and Wolfe 1981) is the dominant methanogenic archaeon of the human gut, reducing CO2 to methane with hydrogen; present in ~95.7% of healthy people, linked to constipation IBS and colorectal cancer, with SCV/LCV/intermediate cell variants.
Methanocaldococcus jannaschii
Methanocaldococcus jannaschii (formerly Methanococcus jannaschii), a hyperthermophilic methanogenic archaeon from East Pacific Rise vents; first archaeal genome sequenced (1996), 1.66 Mbp chromosome, hydrogenotrophic methanogenesis, type strain DSM 2661.
Methanococcaceae
Methanococcaceae (Balch and Wolfe 1981, NCBI txid2183) is a family of flagellated, anaerobic methanogenic archaea in the order Methanococcales, containing the mesophilic Methanococcus and moderately thermophilic Methanothermococcus, which reduce CO2 with H2 to methane.
Methanococcoides burtonii
Methanococcoides burtonii (strain DSM 6242) is a psychrophilic methylotrophic methanogenic archaeon isolated from Ace Lake, Antarctica, growing below 4 to 29 degrees C; first complete genome of a psychrophilic methanogen, adapted via lipid unsaturation and skewed protein composition.
Methanococcus maripaludis
Methanococcus maripaludis, a mesophilic hydrogenotrophic methanogenic archaeon from salt marsh sediments, reduces CO2 to methane with H2 or formate; a fast-growing, genetically tractable model organism with sequenced strains S2 and JJ.
Methanogen
Methanogens (methanogenic archaea) are obligately anaerobic Archaea that must produce methane via the Wolfe Cycle and MCR enzyme to grow; substrates include CO2+H2, acetate, and methylated compounds; their odd 16S rRNA led Woese to discover archaea in 1977.
Methanogenesis
Methanogenesis, also known as biomethanation or methane biosynthesis, is the production of methane by anaerobic archaea called methanogens, occurring in wetlands, sediments, and animal digestive tracts.
Methanogenesis inhibitors in livestock feed
Feed additives that suppress rumen archaea responsible for enteric methane, about 5% of global greenhouse gas emissions; 3-NOP (Bovaer) and bromoform-bearing Asparagopsis seaweed are the only additives proven to cut methane over 20%.
Methanogenic archaeal orders
The methanogenic archaeal orders are seven order-level taxa of methane-producing archaea, including Methanobacteriales, Methanococcales, Methanomicrobiales, Methanosarcinales, and Methanopyrales, defined by 16S rRNA sequences and physiology.
Methanogens in ruminant and animal digestion
Methanogens in ruminant and animal digestion: rumen archaea, chiefly Methanobrevibacter, that produce methane during anaerobic fermentation, causing 2–12% feed energy loss and enabling dietary mitigation strategies like 3-NOP and macroalgae.
Methanol
Methanol, also called methyl alcohol or wood alcohol, is the simplest alcohol, a clear, flammable liquid used industrially as a solvent, feedstock, and fuel, and highly toxic to humans.
Methanol fuel
Methanol fuel, also known as wood alcohol, is methanol (CH₃OH) used as a fuel for internal combustion engines, fuel cells, and increasingly ships, where it cuts sulfur and particulate emissions.
Methanol oxidation reaction
The methanol oxidation reaction (MOR) is the six-electron electrochemical oxidation of methanol to CO2, the anode reaction of the direct methanol fuel cell where it limits performance.
Methanol poisoning
Methanol poisoning (wood alcohol, methyl alcohol toxicity): formic acid metabolites cause metabolic acidosis and blindness after a 12-24 hour latent period; treated with fomepizole, folinic acid, and hemodialysis.