Biphenyl

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Related to biphenyls: Polybrominated biphenyls, Aroclor

biphenyl

[bī′fen·əl]
(organic chemistry)
C12H10 A white or slightly yellow crystalline hydrocarbon, melting point 70.0°C, boiling point 255.9°C, and density 1.9896, which gives plates or monoclinic prismatic crystals; used as a heat-transfer medium and as a raw material for chlorinated diphenyls. Also known as diphenyl; phenylbenzene.

Biphenyl

 

C6H5—C6H5; colorless crystals. Melting point, 71°C; boiling point, 254°-255°C. It is insoluble in water and readily soluble in organic solvents. It is present in the anthracene oil produced from coal tar. It is prepared industrially by dehydrogenation of benzene at 750°–800°C.

Biphenyl is an intermediate in the production of some dyes; mixed with phenyl ether (73.5 percent), it is used as a high-temperature heat carrier (so-called Dowtherm).

References in periodicals archive ?
Development after exposure to polychlorinated biphenyls and dichlorodiphenyl dichloroethene transplacentally and through human milk.
The production of polychlorinated biphenyls (PCBs) was banned worldwide by 1977, but the chemicals linger in the environment at hazardous waste sites, in contaminated fish and food supplies, and in old appliances.
RM 8504, Transformer Oil, is intended to be used as a diluent oil with transformer oil Standard Reference Materials (SRMs) 3075 to 3080 and SRM 3090 [1] when developing and validating methods for the determination of polychlorinated biphenyls (PCBs) as Aroclors (1) in transformer oil or similar matrices.
Chapter titles: Introduction to food toxicology; Part I Assessing and managing risks: Genetic susceptibility to dietary carcinogens; Assessing the mutagenicity of chemicals in food: the case of pesticides: The impact of chemical residues: the case of polychlorinated biphenyls (PCBs): Targeted and rapid methods in analysing residues in food; Good agricultural practice and HACCP systems in the management of pesticides and veterinary residues on the farm.
Polychlorinated biphenyls (PCBs) are manmade chemicals and well-known contaminants prevalent in both terrestrial and aquatic ecosystems.
Ontario, Canada) has patented a method for the safe and efficient degradation of Polychlorinated biphenyls (PCBs) in PCB-contaminated soil into non-hazardous by products.
This (Research Triangle Institute) report presents a toxicological profile of polychlorinated biphenyls (PCBs).
The United States banned PCBs, or polychlorinated biphenyls, for a variety of industrial uses after they were found in the 1970s to cause cancer.
The deadline has long since passed for electric transformers containing dangerous polychlorinated biphenyls (PCBs) to be rendered safe, replaced or electrically protected.
Often referred to as the "lead-free" directive, the Restriction of Hazardous Substances Directive (RoHS) 2002/95/EC [1] restricts the use of hazardous materials [lead, mercury, cadmium, hexavalent chromium (Chromium VI or Cr6+), polybrominated biphenyls (PBB) and PBDE (polybrominated diphenyl ether)] in the manufacture of various types of electronic and electrical equipment.
2 million would generate capacity for disposal of Polychlorinated Biphenyls in future.
Researchers at the State University of New York at Albany and the Florida Fish and Wildlife Conservation Commission in Melbourne teamed up to measure flame retardants called polybrominated diphenyl ethers (PBDEs) and the electric-insulation compounds known as polychlorinated biphenyls (PCBs).