ion exchange chromatography
51dating — I In geology and archaeology, the process of determining an object s or event s place within a chronological scheme. Scientists may use either relative dating, in which items are sequenced on the basis of stratigraphic clues (see stratigraphy) or …
52RNA polymerase — RNAP from T. aquaticus pictured during elongation. Portions of the enzyme were made transparent so as to make the path of RNA and DNA more clear. The magnesium ion (yellow) is located at the enzyme active site. RNA polymerase (RNAP or RNApol) is… …
53cellulose — A linear B1→4 glucan, composed of cellobiose residues, differing in this respect from starch, which is comprised of maltose residues; it forms the basis of vegetable and wood fiber and is the most abundant organic compound; useful in providing… …
54PEGylation — Polyethylene glycol PEGylation is the process of covalent attachment of polyethylene glycol polymer chains to another molecule, normally a drug or therapeutic protein. PEGylation is routinely achieved by incubation of a reactive derivative of PEG …
55Chemical equilibrium — In a chemical reaction, chemical equilibrium is the state in which the concentrations of the reactants and products have not yet changed with time. It occurs only in reversible reactions, and not in irreversible reactions. Usually, this state… …
56Taicatoxin — (TCX) is a snake toxin that blocks voltage dependent L type calcium channels and small conductance Ca2+ activated K+ channels. The name taicatoxin (TAIpan + CAlcium + TOXIN) is derived from its natural source, the taipan snake, the site of its… …
57Spedding , Frank Harold — (1902–1984) American chemist Spedding was born at Hamilton, Ontario, in Canada and educated at the University of Michigan and Berkeley where he obtained his PhD in 1929. After working at Cornell from 1935 to 1937, he moved to Iowa State… …
58Yttrium — (pronEng|ˈɪtriəm) is a chemical element with symbol Y and atomic number 39. It is a silvery metallic transition metal chemically similar to the lanthanoids and has historically been classified as a rare earth element. Yttrium is almost always… …
59Europium — (pronEng|jʊˈroʊpiəm) is a chemical element with the symbol Eu and atomic number 63. It was named after the continent Europe. Characteristics Europium is the most reactive of the rare earth elements; it rapidly oxidizes in air, and resembles… …
60Conductividad (electrolítica) — La conductividad (o conductancia específica) de una solución de electrolito es una medida de su capacidad para conducir la electricidad. La unidad SI de conductividad es el siemens por metro (S/m). Las medidas de conductividad se utilizan de… …
