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Pages in category "Chemical articles with multiple CAS registry numbers" The following 200 pages are in this category, out of approximately 1,423 total. This list may not reflect recent changes. (previous page) *
Screenshot of the CAS Common Chemistry database with information about caffeine ().. A CAS Registry Number [1] (also referred to as CAS RN [2] or informally CAS Number) is a unique identification number, assigned by the Chemical Abstracts Service (CAS) in the US to every chemical substance described in the open scientific literature, in order to index the substance in the CAS Registry.
In PCBs, some of the hydrogen atoms in biphenyl are replaced by chlorine atoms. There are 209 different chemical compounds in which one to ten chlorine atoms can replace hydrogen atoms. PCBs are typically used as mixtures of compounds and are given the single identifying CAS number 1336-36-3. About 130 different individual PCBs are found in ...
A key difference between a registration system and a simple chemical database is the ability to accurately represent that which is known, unknown, and partially known. For example, a chemical database might store a molecule with stereochemistry unspecified, whereas a chemical registry system requires the registrar to specify whether the stereo ...
The acyclic form of xylose has chemical formula HOCH 2 (CH(OH))3CHO. The cyclic hemiacetal isomers are more prevalent in solution and are of two types: the pyranoses, which feature six-membered C 5 O rings, and the furanoses, which feature five-membered C 4 O rings (with a pendant CH 2 OH group). Each of these rings is subject to further ...
E.coli are shown to be more sensitive to accumulations of guanosine tetraphosphate than guanosine pentaphosphate. [7] A complete absence of (p)ppGpp causes multiple amino acid requirements, poor survival of aged cultures, aberrant cell division, morphology, and immotility, as well as being locked in a growth mode during entry into starvation.
The pictogram for harmful substances of the Globally Harmonized System of Classification and Labelling of Chemicals.. The Globally Harmonized System of Classification and Labelling of Chemicals (GHS) is an internationally agreed-upon standard managed by the United Nations that was set up to replace the assortment of hazardous material classification and labelling schemes previously used around ...
Sodium iodide (chemical formula NaI) is an ionic compound formed from the chemical reaction of sodium metal and iodine. Under standard conditions, it is a white, water-soluble solid comprising a 1:1 mix of sodium cations (Na +) and iodide anions (I −) in a crystal lattice. It is used mainly as a nutritional supplement and in organic chemistry.