Oxygen is a chemical element in the periodic table. It has the symbol O and atomic number 8. The element is very common, found not only on Earth but throughout the universe, usually covalently bonded with other elements. Unbound oxygen (usually called molecular oxygen, O2, a diatomic molecule) first appeared on Earth during the Paleoproterozoic era (between 2500 million years ago and 1600 million years ago) and as a product of the metabolic action of early anaerobes (archaea and bacteria). The presence of free oxygen ...

Including:

• Oxygen - Characteristics
• Oxygen - Applications
• Oxygen - History
• Oxygen - Occurrence
• Oxygen - Compounds
• Oxygen - Isotopes
• Oxygen - Precautions

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Oxygen The physical elements are merely the grossest manifestations or reflections on this material plane of invisible, intangible spiritual originants. In this context, all the matter in the universe can be reduced to four substantial elements: carbon, hydrogen, oxygen, and nitrogen. In the first manifested triad -- Mother, Father-Son-Husband, Son -- Oxygen corresponds to Father-Son-Husband; thus, the names of the chemical elements are also used to denote the subtler, more ethereal or spiritual elements from which they proceed.

"We would call hydrogen and oxygen (which instills the fire of life into the 'Mother' by incubation) in the pregenetic and even pre-geological ages -- the Spirit, the noumenon of that which becomes in its grossest form oxygen and hydrogen and nitrogen on Earth -- nitrogen being of no divine origin, but merely an earth-born cement to unite other gases and fluids, and serve as a sponge to carry in itself the breath of LIFE -- pure air" (SD 1:626). Oxygen corresponds to vitality or prana in the lower quaternary of human principles. Moreover, an elixir of life is said to be produced alchemically from ozone, an allotrope of oxygen (SD 1:144).

(See also: Oxygen, Mysticism, Mysticism Dictionary)

Liquid oxygen finds use as an oxidizer in rocket propulsion. Oxygen is essential to respiration, so oxygen supplementation has found use in medicine (as oxygen therapy). People who climb mountains or fly in airplanes sometimes have supplemental oxygen supplies (as air). Oxygen is used in welding (such as the oxyacetylene torch), and in the making of steel and methanol. Oxygen presents two absorption bands centered in the wavelengths 687 and 760 nanometers. Some scientists have proposed to use the measurement of the radiance coming fro ...

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Oxygen, Oxygen - Characteristics, Oxygen - Applications, Oxygen - History, Oxygen - Occurrence, Oxygen - Compounds, Oxygen - Isotopes, Oxygen - Precautions

Read more here: » Oxygen: Encyclopedia II - Oxygen - Applications

Depending on your training and environment, you might have an oxygen first aid set at your disposal. If a patient is in a state of respiratory arrest, use a 100% mask (airtight mask) and an air balloon. This will help you ventilate the patient with pure oxygen, while "manual" insufflations will only provide about 17% oxygen to the patient. A patient whose lungs are full of pure oxygen can stay in apnea for nearly 30 minutes (half an hour). Thus, pure oxygen is a great help which will allow you to perform urgent duty and ...

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Artificial respiration, Artificial respiration - Insufflations, Artificial respiration - Oxygen, Artificial respiration - History

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At standard temperature and pressure, oxygen exists as a diatomic molecule with the formula O2, in which the two oxygen atoms are doubly bonded to each other. In its most stable form, oxygen exists as a diradical (triplet oxygen). Though radicals are commonly associated with highly reactive compounds, triplet oxygen is surprisingly (and fortunately) unreactive towards most compounds. Singlet oxygen, a name given to several higher energy species in which all the electron spins are paired, is much more ...

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Oxygen, Oxygen - Characteristics, Oxygen - Applications, Oxygen - History, Oxygen - Occurrence, Oxygen - Compounds, Oxygen - Isotopes, Oxygen - Precautions

Read more here: » Oxygen: Encyclopedia II - Oxygen - Characteristics

The basic oxygen furnace is the place within a foundry where molten iron from the blast furnace is changed into liquid steel. The vast majority of steel manufactured in the world is produced using the basic oxygen furnace. It is the most common way for steel to be made in the United Kingdom. Modern furnaces will take a charge of iron of up to 350 tons and convert it into steel in less than 40 minutes. Oxygen is blown into the furnace or BOS vessel through a water cooled oxygen lance, like the LD converter. This oxidises carbon ...

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In environmental chemistry, the chemical oxygen demand (COD) test is commonly used to indirectly measure the amount of organic compounds in water. Most applications of COD determine the amount of organic pollutants found in surface water (e.g. lakes and rivers), making COD a useful measure of water quality. It is expressed in millgrams per liter (mg/L), which indicates the mass of oxygen consumed per liter of solution. Older references may express the units as parts per million (ppm). Chemical oxygen demand - Over ...

Including:

• Chemical oxygen demand - Overview
• Chemical oxygen demand - History
• Chemical oxygen demand - Using potassium dichromate
• Chemical oxygen demand - Blanks
• Chemical oxygen demand - Measurement of excess
• Chemical oxygen demand - Calculations
• Chemical oxygen demand - Inorganic interference
• Chemical oxygen demand - Government regulation

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Vanabins (also known as vanadium-associated proteins or vanadium chromagen) are a class of metalloproteins containing vanadium. Found only in the blood of some ascidians and tunicates (sea squirts), these organisms are able to concentrate vanadium to a level more than 100 times higher than in the surrounding seawater. Vanabin proteins seem to be involved in collecting and accumulating this metal ion. At present there is no conclusive understanding of why these organisms collect vanadium, and it remains a biological myste ...

Including:

• Vanabins - Theories
• Vanabins - Vanabins as oxygen carriers
• Vanabins - Vanabins not oxygen carriers
• Vanabins - Technological use of vanabins

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Asphyxia or asphyxiation is a condition of severely deficient supply of oxygen to the body. In the absence of remedial action it will very rapidly lead to unconsciousness and death. Asphyxia is the same as suffocation. It comes from the Greek roots a-, "without" and sphuxis, "pulse, heartbeat". Anoxia means the pathological state in which tissues do not get (enough of) oxygen. Asphyxia in humans is a medical emergency. Prolonged asphyxia can result in ...

Including:

• Asphyxia - Causes
• Asphyxia - Use in suicide and execution

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Apnea (British spelling - apnoea) (Greek απνοια, from α-, privative, πνεειν, to breathe) is a technical term for suspension of external breathing. During apnea there is no movement of the muscles of respiration and the volume of the lungs initially remains unchanged. Depending on the patency of the airways there may or may not be a flow of gas between the lungs and the environment; gas exchange within the lungs and cellular respiration is not affected. Apnea can be voluntarily achieved (i.e., "holding one's breath" ...

Including:

• Apnea - Mechanism
• Apnea - Hyperventilation
• Apnea - Apneic oxygenation

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Artificial respiration is a technique for providing air for a person who is not breathing on their own but whose heart is still beating. The provider breathes into the other person's lungs, preferably with the assistance of a barrier device. Artificial respiration is part of performing cardiopulmonary resuscitation (CPR) but is also performed separately, especially in near-drowning and similar situation ...

Including:

• Artificial respiration - Insufflations
• Artificial respiration - Oxygen
• Artificial respiration - History

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Drowning is death caused by the filling of the lungs by a fluid, usually water, rendering breathing impossible and leading to death due to asphyxia. Near drowning is initial survival of a drowning accident, and can lead to serious secondary complications including death later on; cases of near drowning therefore also require attention by medical professionals. Secondary drowning is death due to chemical and biological changes in the lungs after a near drowning incident or exposure to chemicals. In many countries, drownin ...

Including:

• Drowning - Occurrences
• Drowning - The drowning process
• Drowning - Common situations leading to drowning
• Drowning - Initial Reactions to Submersion
• Drowning - Initial Oxygen Starvation
• Drowning - Water entering the upper airways
• Drowning - Unconsciousness due to Oxygen Starvation
• Drowning - Secondary drowning
• Drowning - Cardiac Arrest and Death
• Drowning - Rescue and Treatment
• Drowning - Prevention

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Ether is the general name for a class of chemical compounds which contain an ether group — an oxygen atom connected to two (substituted) alkyl groups. A typical example is the solvent and anesthetic diethyl ether (ethoxyethane, CH3-CH2-O-CH2-CH3). Ether - Similar structures. Ethers are not to be confused with the following classes of compounds with the same general structure R-O-R. Aromatic compounds like furan where the oxygen is part of the aromat ...

Including:

• Ether - Similar structures
• Ether - Primary secondary and tertiary ethers
• Ether - Polyethers
• Ether - Chemical reactions
• Ether - Synthesis
• Ether - Reactions
• Ether - Physical properties
• Ether - Nomenclature
• Ether - Important ethers

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The water injection method used in oil production is where water is injected back into the reservoir usually to increase pressure and thereby stimulate production. Water injection wells can be found both on- and offshore. This method is used to increase oil recovery from an existing reservoir. Water is injected for two reasons: 1. For pressure support of the reservoir (also known as voidage replacement). 2. To sweep or displace ...

Including:

• Water injection oil production - Injected Water Sources
• Water injection oil production - Filters
• Water injection oil production - De-oxygenation tower
• Water injection oil production - Water injection pumps

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In humans, there are several types of oxygen toxicity: Central nervous system (CNS) oxygen toxicity is manifested as convulsions, which although not lethal themselves, can cause drowning of divers or lethal pressure damage during a rapid ascent. The likelihood of this type of accident is directly proportional to the partial pressure of oxygen (ppO2) in the breathing gas and to the duration of exposure. Pulmonary oxygen toxicity is caused by exposure over 16 hours ...

See also:

Oxygen toxicity, Oxygen toxicity - Hyperoxia, Oxygen toxicity - Common causes, Oxygen toxicity - Types of oxygen toxicity, Oxygen toxicity - Avoiding oxygen toxicity while diving

Read more here: » Oxygen toxicity: Encyclopedia II - Oxygen toxicity - Types of oxygen toxicity

Oxygen depletion could be the result of a number of factors including natural ones, but is of most concern as a consequence of pollution and as a highly detrimental outcome of a process known as eutrophication. Where plant nutrients enter a river, lake, or ocean, phytoplankton blooms are encouraged. While phytoplankton, through photosynthesis, will raise DO saturation during daylight hours, the dense population of a bloom reduces DO saturation during the night. When phytoplankton cells die, they sink towards the bottom and are decomposed by ...

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Oxygen depletion, Oxygen depletion - Causes of oxygen depletion, Oxygen depletion - Solutions, Oxygen depletion - External link

Read more here: » Oxygen depletion: Encyclopedia II - Oxygen depletion - Causes of oxygen depletion

The presence of atmospheric oxygen has led to the formation of ozone and the ozone layer within the stratosphere. The ozone layer is extremely important to modern life as it absorbs harmful ultraviolet radiation: O2 + uv energy → 2O O + O2 + uv energy → O3 The absorbed solar energy also raises the temperature of the atmosphere within the ozone layer creating a thermal barrier that helps trap the atmosphere below (a ...

See also:

Oxygen cycle, Oxygen cycle - Ozone, Oxygen cycle - Phosphorus

Read more here: » Oxygen cycle: Encyclopedia II - Oxygen cycle - Ozone

There is an increased risk of CNS oxygen toxicity on deep dives, long dives or dives where oxygen-rich breathing gases are used. Divers are taught, in some diver training courses for these types of diving, to plan and monitor what is called the "oxygen clock" of their dives. This clock is a notional alarm clock, which "ticks" more quickly at increased ppO2 and is set to activate at these maximum single exposure limits recommended in the NOAA Diving Manual: 45 minutes at 1.6 bar, of 120 min ...

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Oxygen toxicity, Oxygen toxicity - Hyperoxia, Oxygen toxicity - Common causes, Oxygen toxicity - Types of oxygen toxicity, Oxygen toxicity - Avoiding oxygen toxicity while diving

Read more here: » Oxygen toxicity: Encyclopedia II - Oxygen toxicity - Avoiding oxygen toxicity while diving

To combat hypoxia, it is essential to reduce the amount of land-derived nutrients reaching rivers in runoff. Defensively this can be done by improving sewage treatment and by reducing the amount of fertilizers leaching into the rivers. Offensively this can be done by restoring natural environments along a river; marshes are particularly effective in reducing the amount of phosphorus and nitrogen (nutrients) in water. In a very short time the oxygen saturation can drop to zero when offshore blowing winds drive surface water out and ano ...

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Oxygen depletion, Oxygen depletion - Causes of oxygen depletion, Oxygen depletion - Solutions, Oxygen depletion - External link

Read more here: » Oxygen depletion: Encyclopedia II - Oxygen depletion - Solutions

A chlorate candle, or an oxygen candle, is a cylindrical chemical oxygen generator containing a mix of sodium chlorate and iron powder. When ignited, the mixture smolders at about 600 °C, producing sodium chloride, iron oxide, and about 6.5 man-hours of oxygen per kilogram of the mixture. It releases oxygen in a fixed rate. The mixture has an indefinite shelf life if stored properly; candles stored for 20 years have shown no decrease in oxygen output. The oxygen is released by thermal decomposition, the heat is supplied by the ...

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Chemical oxygen generator, Chemical oxygen generator - Oxygen candle, Chemical oxygen generator - Solid oxygen generator from MIR, Chemical oxygen generator - Uses

Read more here: » Chemical oxygen generator: Encyclopedia II - Chemical oxygen generator - Oxygen candle