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Download as PDF; Printable version; In other projects ... This is a list of web testing tools, ... Selenium: Yes (IE, Firefox, Chrome, Safari, Opera, Edge)
Selenium is a component of the amino acids selenocysteine and selenomethionine. In humans, selenium is a trace element nutrient that functions as cofactor for glutathione peroxidases and certain forms of thioredoxin reductase. [1] Selenium-containing proteins are produced from inorganic selenium via the intermediacy of selenophosphate (PSeO 3 3 ...
Selenium is found in metal sulfide ores, where it substitutes for sulfur. Commercially, selenium is produced as a byproduct in the refining of these ores. Minerals that are pure selenide or selenate compounds are rare. The chief commercial uses for selenium today are glassmaking and pigments. Selenium is a semiconductor and is used in photocells.
Selenium Grid is a server that allows tests to use web browser instances running on remote machines. With Selenium Grid, one server acts as the central hub. Tests contact the hub to obtain access to browser instances. The hub has a list of servers that provide access to browser instances (WebDriver nodes), and lets tests use these instances.
Selones (R 2 C=Se) are the selenium analogues of ketones. They are rare due to their tendency to oligomerize. [11] Diselenobenzoquinone is stable as a metal complex. [12] Selenourea is an example of a stable compound containing a (formal) C=Se bond. Thioselenides (R−Se−S−R), compounds with selenium(II)–sulfur(II) bonds, analogous to ...
Selenium forms two oxides: selenium dioxide (SeO 2) and selenium trioxide (SeO 3). Selenium dioxide is formed by the reaction of elemental selenium with oxygen: [5] + It is a polymeric solid that forms monomeric SeO 2 molecules in the gas phase. It dissolves in water to form selenous acid, H 2 SeO 3.
Selenium is toxic in high concentrations. As sodium selenite, the chronic toxic dose for human beings was described as about 2.4 to 3 milligrams of selenium per day. [7] In 2000, the US Institute of Medicine set the adult Tolerable upper intake levels (UL) for selenium from all sources - food, drinking water and dietary supplements - at 400 μg/day. [8]
Selenomethionine (SeMet) is a naturally occurring amino acid.The L-selenomethionine enantiomer is the main form of selenium found in Brazil nuts, cereal grains, soybeans, and grassland legumes, while Se-methylselenocysteine, or its γ-glutamyl derivative, is the major form of selenium found in Astragalus, Allium, and Brassica species. [1]