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This is a complete list of polychlorinated biphenyl (PCB) congeners. Chemical structure of PCBs. The possible positions of chlorine atoms on the benzene rings are denoted by numbers assigned to the carbon atoms.
PCB warning label on a power transformer known to contain PCBs. Polychlorinated biphenyls (PCBs) are organochlorine compounds with the formula C 12 H 10−x Cl x; they were once widely used in the manufacture of carbonless copy paper, as heat transfer fluids, and as dielectric and coolant fluids for electrical equipment. [2]
There are 209 PCB compounds. Analogously to PCDDs at least two lateral chlorines in each ring in positions 3,4, and/or 5 are needed for dioxin-like activity. Because the AH receptor requires a planar (flat) structure, only PCB congeners that can rotate freely along the C—C axis between the rings can attach the receptor.
2,2',3,3',4,4'-Hexachlorobiphenyl is an organic chemical and belongs to a group of compounds called polychlorinated biphenyls. This group of organic compounds was used in transformers as dielectric fluids, until production was banned in 1979.
A group of carcinogenic organic compounds, polychlorinated biphenyls (PCBs), is an example of a congener grouping. The number and locations of Cl groups can vary. In chemistry, congeners are chemical substances "related to each other by origin, structure, or function". [1]
General structure of a PCB. Polychlorinated biphenyls (PCBs) are various biphenyl based artificial products that are widely used as a dielectric fluid, industrial coolant, and lubricants in the 1960s and 1970s. There is no evidence its synthesis occurs naturally. They are classified as persistent organic pollutants.
Bare die supplied without a package. It is mounted directly to the PCB using bonding wires and covered with a blob of black Epoxy. [22] Also used for LEDs. In LEDs, transparent epoxy or a silicon caulk-like material that may contain a phosphor is poured into a mold containing the LED(s) and cured. The mold forms part of the package. COF: Chip ...
Biphenyl (also known as diphenyl, phenylbenzene, 1,1′-biphenyl, lemonene [4] or BP) is an organic compound that forms colorless crystals. Particularly in older literature, compounds containing the functional group consisting of biphenyl less one hydrogen (the site at which it is attached) may use the prefixes xenyl or diphenylyl.