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Coal tar causes increased sensitivity to sunlight, [55] so skin treated with topical coal tar preparations should be protected from sunlight. The residue from the distillation of high-temperature coal tar, primarily a complex mixture of three or more membered condensed ring aromatic hydrocarbons , was listed on 13 January 2010 as a substance of ...
One can produce a tar-like substance from corn stalks by heating them in a microwave oven. This process is known as pyrolysis. Tar is a dark brown or black viscous liquid of hydrocarbons and free carbon, obtained from a wide variety of organic materials through destructive distillation. Tar can be produced from coal, wood, petroleum, or peat. [1]
Natural bitumen pitch, from the tar pit above the McKittrick Oil Field, Kern County, California. Pitch is a viscoelastic polymer which can be natural or manufactured, derived from petroleum, coal tar, [1] or plants. Pitch produced from petroleum may be called bitumen or asphalt, while plant-derived pitch, a resin, is known as rosin in its solid ...
The term creosote has a broad range of definitions depending on the origin of the coal tar oil and end-use of the material. With respect to wood preservatives, the United States Environmental Protection Agency (EPA) considers the term creosote to mean a pesticide for use as a wood preservative meeting the American Wood Protection Association (AWPA) Standards P1/P13 and P2. [6]
Styrene is named after storax balsam (often commercially sold as styrax), the resin of Liquidambar trees of the Altingiaceae plant family. Styrene occurs naturally in small quantities in some plants and foods ( cinnamon , coffee beans , balsam trees and peanuts ) [ 7 ] and is also found in coal tar .
The use of coal as fuel causes health problems and deaths. [123] The mining and processing of coal causes air and water pollution. [124] Coal-powered plants emit nitrogen oxides, sulfur dioxide, particulate pollution, and heavy metals, which adversely affect human health. [124] Coal bed methane extraction is important to avoid mining accidents.
Bituminous coal. Bituminous coal, or black coal, is a type of coal containing a tar-like substance called bitumen or asphalt. Its coloration can be black or sometimes dark brown; often there are well-defined bands of bright and dull material within the seams. It is typically hard but friable.
Juglone is an example of such a molecule inhibiting the growth of other plant species around walnut trees. [ citation needed ] The aquatic vascular plant Myriophyllum spicatum produces ellagic , gallic and pyrogallic acids and (+)- catechin , allelopathic phenolic compounds inhibiting the growth of blue-green alga Microcystis aeruginosa .