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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 ...
Asphalt (naturally occurring pitch) may also be called either "mineral tar" or "mineral pitch". There is a tendency to use "tar" for more liquid substances and "pitch" for more solid (viscoelastic) substances. [2] Both "tar" and "pitch" are applied to viscous forms of asphalt, such as the asphalt found in naturally occurring tar pits (e.g., the ...
The term naval stores originally applied to the organic compounds used in building and maintaining wooden sailing ships, a category which includes cordage, mask, turpentine, rosin, pitch and tar. These materials were originally used for water- and weather-proofing wooden ships.
With the demise of wooden ships, those uses of pine resin ended, but the former naval stores industry remained vigorous as new products created new markets. First extensively described by Frederick Law Olmsted in his book A Journey in the Seaboard Slave States (1856), [3] the naval stores industry was one of the economic mainstays of the southeastern United States until the late 20th century.
La Brea Tar Pits is an active paleontological research site in urban Los Angeles. Hancock Park was formed around a group of tar pits where natural asphalt (also called asphaltum, bitumen, or pitch; brea in Spanish) has seeped up from the ground for tens of thousands of years.
The HIV trans-activation response (TAR) element is an RNA element which is known to be required for the trans-activation of the viral promoter and for virus replication. The TAR hairpin is a dynamic structure [ 1 ] that acts as a binding site for the Tat protein , and this interaction stimulates the activity of the long terminal repeat promoter.
Birch bark tar use as an adhesive began in the Middle Paleolithic. Neanderthals produced tar through dry distillation of birch bark as early as 200,000 years ago. [6] A 2019 study demonstrated that birch bark tar production can be a simpler, more discoverable process by directly burning birch bark under overhanging stone surfaces in open-air conditions. [7]
Pitch (resin) – Natural or manufactured resin Kino (gum) – plant gum Pages displaying wikidata descriptions as a fallback Biodegradable – Decomposition by living organisms Pages displaying short descriptions of redirect targets – plant resins are naturally biodegradable in many circumstances.