#Ammon

• Ammoniation — The act of ammoniating and its result; a technological or industrial process through which gaseous or liquid ammonia is introduced into a chemical environment, solutions, or a solid substrate, aiming to modify its acidity, structural reactivity, or nitrogen content. In applied ecology, the term is sometimes used as a partial synonym for ammonification, describing the initial release phase of ammonia from residues.
• Ammonoids — Scientific name or higher taxonomic classification (Ammonoidea) that includes all species of fossil marine cephalopod mollusks related to true ammonites, globally distributed from the Devonian to the Cretaceous. These prehistoric organisms are distinguished by the unique structure of their external, spiraled, and chambered shells, serving as essential index fossils in stratigraphy.
• Ammonolysis — A chemical cleavage reaction of a bond in an organic or inorganic compound under the action of ammonia, analogous to hydrolysis, resulting in the introduction of amino groups (-NH2) into the structure of the resulting molecule. This industrial process is widely used for synthesizing amines, amides, and other nitrogenous derivatives from alkyl halides, acids, or esters.
• Ancyloceras — A genus of fossil ammonites from the Early Cretaceous period, characterized by a partially uncoiled or unusually bent shell, often with an initial spiraled portion followed by a straight shaft and a final hook-like bend. It represents a reference organism in biostratigraphy for the precise dating of marine geological strata.
• Anisian — A geological stage or substage located at the base of the Middle Triassic epoch, chronologically spanning from approximately 247 to 242 million years ago. As an adjective, the term refers to rocks, sediments, or fossils formed during this time interval, internationally defined by the appearance of specific ammonite and conodont assemblages within reference Alpine geological sections.
• Ammonium hydroxide — An aqueous solution of ammonium hydroxide (NH₄OH), a clear, colorless liquid with a pungent, suffocating, and strongly alkaline odor, obtained by dissolving ammonia gas in water; it is widely used in the chemical industry as a laboratory reagent, in producing nitrogen fertilizers, cleaning agents, textiles, or as a refrigerant medium.
• Arginase — A highly crucial hydrolytic enzyme, primarily located in the cytoplasm of hepatocytes, which catalyzes the final phase of the urea cycle. This structural biocatalyst splits arginine into ornithine and urea, facilitating the efficient elimination of toxic ammonia resulting from protein metabolism and thus preventing severe neurological disorders.
• Arietites — A fossil genus of ammonites (extinct marine cephalopod mollusks) from the Early Jurassic period, characterized by a large, planospiral shell with prominent transverse ribs and a distinct central keel; the name suggests the resemblance of the coiled shell to the horns of the Egyptian god Ammon or a ram, serving as a critical index fossil for dating geological strata of the Sinemurian stage.
• Aspidoceras — An extinct genus of ammonites (coiled marine cephalopod mollusks) in the family Aspidoceratidae, which lived during the Late Jurassic and Early Cretaceous periods. Fossils of this genus are recognized by their robust, evolute shell, characterized by distinctive rows of nodes or spines arranged on the flanks, used by paleontologists as index fossils for dating marine geological strata.
• Nitrate — A salt or ester of nitric acid containing the NO3 functional group; in common and agricultural language (often called nitrate), it refers to chemical fertilizers used for enriching the soil with nitrogen, whose excessive use can lead to the pollution of groundwater.
• Baculite — A member of the extinct genus Baculites, representing an Upper Cretaceous ammonite characterized by an almost completely straight, elongated, rod-shaped calcareous shell, unlike classic spiraled ammonites. Geologically, baculite fossils are utilized as highly important index fossils for dating marine sedimentary layers and reconstructing prehistoric ecosystems.