All articles starting with O

Oxybenzone

Oxybenzone, also known as benzophenone-3, is an organic compound used as a UV filter in sunscreens; it is widely used but banned in Hawaii since 2021 over coral toxicity.

Oxybutynin (Ditropan, Oxytrol) is an antimuscarinic drug for overactive bladder, first US-approved 1975. Oral bioavailability is 6% with high N-DEO metabolite levels causing dry mouth; transdermal forms reach 80% bioavailability. Also used off-label for hyperhidrosis; flagged for cognitive risk in older adults.

Oxycarboxin

Oxycarboxin (CAS 5259-88-1), also sold as Plantvax, is a systemic oxathiin SDHI (FRAC Group 7) fungicide, the sulfone of carboxin, introduced in 1966 for rust and smut control and now not approved in the EU and unmarketed in the US since 2003.

Oxycerites

Oxycerites (Rollier, 1909) is an extinct Middle Jurassic ammonite genus of the family Oppeliidae, subfamily Oppeliinae, with oxycone shells; recorded from about 172–156 Ma, including Bathonian Kutch, India.

Oxychalcogenide thermoelectrics

Oxychalcogenide thermoelectrics are layered mixed-anion compounds containing oxide and chalcogenide anions, developed for heat-to-electricity conversion; the leading material, BiCuSeO, reported in 2010, offers low thermal conductivity, non-toxic elements, and a figure of merit of about 1.5.

Oxycodegol

Oxycodol (NKTR-181) is a mu-opioid agonist developed by Nektar Therapeutics. It is defined by its slow CNS entry and reduced abuse potential, but it failed regulatory review in 2020.

Oxycodone

Oxycodone: semisynthetic opioid analgesic synthesized from thebaine in Germany in 1916; metabolized mainly by CYP3A4/5 to noroxycodone and CYP2D6 to oxymorphone; extended-release OxyContin is the most commonly misused prescription opioid.

Oxydemeton methyl

Oxydemeton methyl (Metasystox-R, CAS 301-12-2) is a systemic organophosphate insecticide/acaricide for aphids, mites, and thrips; cholinesterase inhibitor, EU-banned, US restricted use, poorly reactivated by oximes after poisoning.

Oxydendrum

Oxydendrum, sourwood (Oxydendrum arboreum), a monotypic genus of Ericaceae; deciduous southeastern US tree with lily-of-the-valley-like white summer flowers, prized honey, red fall color, acid soil needs, IUCN Least Concern.

Oxyeleotris marmorata

Oxyeleotris marmorata, the marbled goby (Soon Hock, Ketutu), is a large Southeast Asian freshwater sleeper (Eleotridae) described by Bleeker in 1852, a high-priced food fish farmed in aquaculture and listed IUCN Least Concern.

Oxyfluorfen

Oxyfluorfen (Goal, Galigan), a diphenyl-ether PPO-inhibiting herbicide (WSSA Group 14) introduced by Dow in 1976, used pre- and post-emergent against broadleaf and grassy weeds in grapes, almonds, cotton, ornamentals, and rights-of-way.

Oxyfuel combustion

Oxyfuel combustion, also written oxy-fuel combustion, burns fuel in nearly pure oxygen with recycled flue gas, yielding a CO2-rich exhaust for carbon capture and storage.

Oxygen

Oxygen is the chemical element with atomic number 8, a colorless, odorless diatomic gas making up 21% of Earth's atmosphere, isolated by Joseph Priestley in 1774.

Oxygen (2017 film)

Oxygen (ఆక్సిజన్) is a 2017 Telugu action thriller directed by A. M. Jyothi Krishna, starring Gopichand, Raashi Khanna, and Anu Emmanuel, with music by Yuvan Shankar Raja; released 30 November 2017 after repeated delays, it follows an army major investigating lethal cigarettes.

Oxygen (2021 film)

Oxygen (French: Oxygène, original title O2) is a 2021 French-language sci-fi survival thriller by Alexandre Aja, starring Mélanie Laurent as an amnesiac trapped in a cryogenic pod with Mathieu Amalric voicing the AI MILO; released on Netflix May 12, 2021.

Oxygen balance

Oxygen balance measures how well an explosive's own oxygen matches what is needed to oxidize its fuel fully, expressed as excess or deficit, negative for TNT.

Oxygen bar

Oxygen bar, or recreational oxygen station: a wellness venue serving scented concentrated oxygen via nasal cannula. Began in Tokyo 1988; O2 Spa Bar Toronto 1996; health claims lack evidence.

Oxygen concentrator

An oxygen concentrator, or PSA oxygen generator, is a medical device that concentrates oxygen from air using pressure swing adsorption, delivering 90–93% oxygen for therapy.

Oxygen Consumption

Oxygen consumption (VO2) is the rate at which tissues or the whole body use oxygen, measured by indirect calorimetry; key units are mL O2/kg/min and METs (1 MET = 3.5 mL O2/kg/min), with VO2max as the main fitness metric.

Oxygen cycle

The oxygen cycle is the biogeochemical cycle through which oxygen moves among the atmosphere, ocean, biosphere, and rocks, produced mainly by photosynthesis and consumed by respiration and weathering.

Oxygen deletion of furans and benzofurans

Oxygen deletion of furans and benzofurans is a class of skeletal-editing reactions that removes the ring oxygen atom from these aromatic heterocycles, typically forming a new carbon–carbon bond.

Oxygen delignification

Oxygen delignification, also called oxygen bleaching or the O stage, is a pulp and paper process that removes residual lignin from kraft pulp before bleaching.

Oxygen electrocatalysis

Oxygen electrocatalysis is the branch of electrocatalysis concerned with the oxygen reduction and oxygen evolution reactions, whose sluggish four-electron kinetics bottleneck fuel cells, water electrolyzers, and metal–air batteries.

Oxygen Generation System

The Oxygen Generation System (OGS) is the International Space Station's primary source of breathable oxygen, electrolyzing reclaimed water in a 28-cell stack and running nearly continuously since 2007.

Oxygen insertion into aryl rings

Oxygen insertion into aryl rings is a skeletal-editing reaction that inserts a single oxygen atom into an arene's carbon framework, yielding lactones or aryl ethers valued in drug discovery.

Sep 29, 2026

Oxygen isotope analysis

Oxygen isotope analysis measures the relative abundance of stable oxygen isotopes in rocks, waters, ice, and biogenic minerals, using those ratios to reconstruct past temperatures and water-cycle history.

Oxygen mask

An oxygen mask is a face covering connected to an oxygen supply that delivers supplemental oxygen, used in medicine for patients and in aviation for low cabin air oxygen.

Oxygen minimum zone

An oxygen minimum zone (OMZ) is a persistent ocean layer, about 100 to 1,500 m deep, where dissolved oxygen falls far above and below levels of nearby waters, and zones are expanding as the ocean warms.

Sep 29, 2026

Oxygen plasma etching

Oxygen plasma etching is a dry process that removes organic materials such as photoresist and polymers, converting them into volatile gases pumped away, chiefly in microfabrication.