Momentum–depth relationship in a rectangular channel Momentum–depth relationship in a rectangular channel In classical physics, momentum is the product of mass and velocity and is a vector quantity, but in fluid mechanics it is treated as a longitudinal quantity (i.e. one dimension) evaluated in the direction of flow. Additionally, it is evaluated as momentum per unit time, corresponding to the product of mass flow rate and velocity, and therefore it has units of force. The momentum forces considered in open channel flow are dynamic force – dependent of depth and flow rate – and static force – dependent of depth – both affected by gravity. The
N,N-Dimethyltryptamine (step 1). The resulting decarboxylated tryptophan analog is tryptamine. Tryptamine then undergoes a transmethylation (step 2): the enzyme indolethylamine-N-methyltransferase (INMT) catalyzes the transfer of a methyl group from cofactor S-adenosyl-methionine (SAM), via nucleophilic attack, to tryptamine. This reaction transforms SAM into S-adenosylhomocysteine (SAH), and gives the intermediate product "N"-methyltryptamine (NMT). NMT is in turn transmethylated by the same process (step 3) to form the end product "N","N"-dimethyltryptamine. Tryptamine transmethylation is regulated by two products of the reaction: SAH, and DMT were shown "ex vivo" to be among the most potent inhibitors of rabbit INMT activity. This transmethylation mechanism has been