All articles starting with O
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Oia, Greece
Oia is a village on the northern tip of Santorini, Greece, famed for caldera sunsets and cave houses. A former captains' village, it is now a protected settlement at the center of the island's overtourism management.
Oikeiôsis (οἰκείωσις)
Oikeiôsis (οἰκείωσις), Stoic 'appropriation' or 'familiarization': the process of recognizing something as one's own, from self-preservation to universal belonging, foundational to Stoic ethics, cosmopolitanism, and later Platonist and early modern reception.
Oikonomos (Ptolemaic Egypt)
The oikonomos, Greek οἰκόνομος, was the nome-level financial official of Ptolemaic Egypt, overseeing tax collection, grain, and royal monopolies under the dioiketes until the office declined in the second century BC.
Oikopleura
Oikopleura is a genus of tiny planktonic tunicates, named in 1830, whose larvaceans build a gelatinous filter-feeding house they discard and rebuild many times a day.
Oikopleura dioica
Oikopleura dioica is a planktonic appendicularian (larvacean) tunicate retaining the chordate tadpole form for life, with a 4-day cycle, the smallest chordate genome (~70 Mb), extreme genome scrambling, and cryptic global species.
Oil
Oil, in the industrial sense, is petroleum: a mixture of hydrocarbons formed underground over millions of years from marine organisms and refined into fuels and other products.
Oil & Gas Development Company
Oil & Gas Development Company Limited (OGDCL) is Pakistan's largest state-owned exploration and production company, established in 1961 and producing about 49% of national oil output.
Oil analysis
Oil analysis, also called used-oil analysis or oil condition monitoring, is the laboratory testing of lubricant from operating machinery to detect wear, contamination, and degraded oil.
Oil and Gas Development Company
Oil and Gas Development Company Limited (OGDCL) is Pakistan's state-controlled oil and gas exploration and production company, headquartered in Islamabad, holding the largest share of the country's reserves and output.
Oil and gas industry in Ghana
The oil and gas industry in Ghana is an offshore petroleum sector producing from the Jubilee, TEN, and Sankofa-Gye Nyame fields, with output peaking in 2019.
Oil and gas industry in India
The oil and gas industry in India, also called the petroleum industry in India, spans exploration, refining, and marketing, with about 88 percent of crude oil imported.
Oil and Gas Methane Partnership 2.0
The Oil and Gas Methane Partnership 2.0 is a UNEP framework, launched in 2020, under which oil and gas companies report methane emissions using measurement-based methods.
Oil and Natural Gas Corporation (तेल एवं प्राकृतिक गैस निगम)
Oil and Natural Gas Corporation (तेल एवं प्राकृतिक गैस निगम), known as ONGC, is an Indian state-owned oil and gas company headquartered in New Delhi, producing about 71 percent of India's domestic oil and gas.
Oil bath (laboratory)
An oil bath is a laboratory setup that heats a reaction vessel in oil, usually mineral or silicone oil, for even heating up to 230 °C.
Oil circuit breaker
An oil circuit breaker is a power circuit breaker that quenches the arc by separating contacts in insulating oil, dominating high-voltage switchgear for most of the twentieth century.
Oil distillation
Oil distillation is the process that heats crude oil and condenses its vapor fractions at different boiling ranges; its crude unit is the first in virtually all refineries.
Oil drop experiment
The oil drop experiment, also known as Millikan's oil drop experiment, is a physics measurement that determined the elementary charge using charged oil droplets between charged plates.
Oil heater
Oil heater (oil-filled radiator, オイルヒーター): portable electric space heater warming a room via factory-sealed diathermic oil heated by an element, never burned; distinct from Japanese kerosene oil heaters (石油ヒーター) and oil-fired boilers; ~1.62 kWh/h measured running cost.
Oil hydrogenation
Oil hydrogenation is a catalytic process that adds hydrogen to unsaturated fatty acids in edible oils, converting liquid oils into solid fats for margarine, shortening, and bakery products.
Oil immersion
Oil immersion is a microscopy technique in which oil replaces the air gap between the objective and cover glass, raising resolution; it is standard for 100X objectives.
Oil in Kenya
Oil in Kenya refers to the country's petroleum resources, first discovered commercially at Ngamia-1 in the South Lokichar Basin, Turkana County, in 2012, with production planned from 2026.
Oil India
Oil India Limited is an Indian state-owned oil and gas exploration and production company headquartered at Duliajan in Assam, incorporated in 1959 to develop the Naharkatiya oilfields.
Oil lamp
An oil lamp, also called an oil lantern, is a device that burns oil through a wick to produce light, used widely until electricity spread in the late 19th century.
Oil on Water
Oil on Water is a 2010 novel by Nigerian writer Helon Habila in which two journalists travel the Niger Delta in search of a kidnapped British woman.
Oil paint
Oil paint is pigment dispersed in a drying oil such as linseed, walnut, or poppy oil, curing by oxidation and polymerization rather than evaporation. Known for slow drying, glazes, impasto, and fat-over-lean layering; dominant in European painting since the sixteenth century.
Oil painting
Oil painting: technique using pigments mixed with a drying oil such as linseed, drying slowly by oxidation. Known from Bamiyan murals around 650 AD; dominant in Europe from the 16th century after van Eyck.
Oil platform
An oil platform, also called an offshore platform, is a structure on the seabed that drills wells and extracts petroleum and natural gas from beneath the ocean floor.
Oil Platforms case
ICJ case in which Iran sued the United States over the 1987 and 1988 destruction of three National Iranian Oil Company offshore complexes; the Court in 2003 rejected both claims for reparation, finding no armed attack justified the strikes and no treaty commerce was impeded.
Oil refinery
An oil refinery, also called a petroleum refinery, is an industrial facility that converts crude oil into products like gasoline, diesel, jet fuel, and asphalt through separation, conversion, and treatment.
Oil reserves in Saudi Arabia
Oil reserves in Saudi Arabia, also called Saudi oil reserves, are estimated at about 267 billion barrels of proven crude oil, roughly 17 percent of the world's reserves.