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Venenivibrio stagnispumantis gains energy by oxidizing hydrogen gas.. In biochemistry, chemosynthesis is the biological conversion of one or more carbon-containing molecules (usually carbon dioxide or methane) and nutrients into organic matter using the oxidation of inorganic compounds (e.g., hydrogen gas, hydrogen sulfide) or ferrous ions as a source of energy, rather than sunlight, as in ...
Sulfur is an essential component of all living cells. It is the eighth most abundant element in the human body by weight, [ 101 ] about equal in abundance to potassium, and slightly greater than sodium and chlorine. [ 102 ] A 70 kg (150 lb) human body contains about 140 grams (4.9 oz) of sulfur. [ 103 ]
Sulfuric acid is a very important commodity chemical; a country's sulfuric acid production is a good indicator of its industrial strength. [9] Many methods for its production are known, including the contact process, the wet sulfuric acid process, and the lead chamber process. [10] Sulfuric acid is also a key substance in the chemical industry.
Sulfur metabolism. Sulfur is metabolized by all organisms, from bacteria and archaea to plants and animals. Sulfur can have an oxidation state from -2 to +6 and is reduced or oxidized by a diverse range of organisms. [1] The element is present in proteins, sulfate esters of polysaccharides, steroids, phenols, and sulfur-containing coenzymes.
Synthetic element. A synthetic element is one of 24 known chemical elements that do not occur naturally on Earth: they have been created by human manipulation of fundamental particles in a nuclear reactor, a particle accelerator, or the explosion of an atomic bomb; thus, they are called "synthetic", "artificial", or "man-made".
Amino acid biosynthesis is the set of biochemical processes (metabolic pathways) by which the amino acids are produced. The substrates for these processes are various compounds in the organism 's diet or growth media. Not all organisms are able to synthesize all amino acids. For example, humans can synthesize 11 of the 20 standard amino acids.
Examples include nitric acid (from ammonia), sulfuric acid (from sulfur dioxide to sulfur trioxide by the contact process), terephthalic acid from p-xylene, acrylic acid from propylene or propane and acrylonitrile from propane and ammonia. [22] The production of ammonia is one of the largest-scale and most energy-intensive processes.
Fertilizer production is now the largest source of human-produced fixed nitrogen in the terrestrial ecosystem. Ammonia is a required precursor to fertilizers , explosives , and other products. The Haber process requires high pressures (around 200 atm) and high temperatures (at least 400 °C), which are routine conditions for industrial catalysis.