Engineering

A prosthetic leg with 'feeling' improves mobility

A breakthrough device unveiled Monday makes it possible for someone amputated above the knee to "feel" a prosthetic leg, resulting is greater stamina, stability and mobility.

Energy & Green Tech

New organic flow battery brings decomposing molecules back to life

After years of making progress on an organic aqueous flow battery, Harvard University researchers ran into a problem: the organic anthraquinone molecules that powered their ground-breaking battery were slowly decomposing ...

Engineering

Laser technology helps researchers scrutinize cancer cells

Devising the best treatment for a patient with cancer requires doctors to know something about the traits of the cancer from which the patient is suffering. But one of the greatest difficulties in treating cancer is that ...

Engineering

Students develop band device for opioid overdose alerts

Anyone familiar with statistics and headlines about opioid addiction was not shocked to see that in the United States by late 2017 opioid addiction was declared a national public health emergency.

Computer Sciences

Prescience: Helping doctors predict the future

During surgery, anesthesiologists monitor and manage patients to make sure they are safe and breathing well. But these doctors can't always predict when complications will arise.

Energy & Green Tech

Battery leverages both iron and oxygen to drive more lithium ions

On paper, it doesn't seem like Christopher Wolverton's super lithium-rich battery should work. For one, the novel battery uses iron, an inexpensive metal that has notoriously failed in batteries. And in another difficult ...

Energy & Green Tech

An effective and low-cost solution for storing solar energy

How can we store solar energy for period when the sun doesn't shine? One solution is to convert it into hydrogen through water electrolysis. The idea is to use the electrical current produced by a solar panel to 'split' water ...

Engineering

Tattoo-like skin health monitor needs no batteries

(Tech Xplore)—An international team of researchers has developed an ultra-thin health monitoring device that affixes to the skin like a patch and looks somewhat like a tattoo. As they note in their paper published in the ...

Energy & Green Tech

Bionic leaf turns sunlight into liquid fuel

The days of drilling into the ground in the search for fuel may be numbered, because if Daniel Nocera has his way, it'll just be a matter of looking for sunny skies.

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Oxygen

Oxygen (pronounced /ˈɒksɨdʒɨn/, from the Greek roots ὀξύς (oxys) (acid, literally "sharp", from the taste of acids) and -γενής (-genēs) (producer, literally begetter) is the element with atomic number 8 and represented by the symbol O. It is a member of the chalcogen group on the periodic table, and is a highly reactive nonmetallic period 2 element that readily forms compounds (notably oxides) with almost all other elements. At standard temperature and pressure two atoms of the element bind to form dioxygen, a colorless, odorless, tasteless diatomic gas with the formula O2. Oxygen is the third most abundant element in the universe by mass after hydrogen and helium and the most abundant element by mass in the Earth's crust. Diatomic oxygen gas constitutes 20.9% of the volume of air.

All major classes of structural molecules in living organisms, such as proteins, carbohydrates, and fats, contain oxygen, as do the major inorganic compounds that comprise animal shells, teeth, and bone. Oxygen in the form of O2 is produced from water by cyanobacteria, algae and plants during photosynthesis and is used in cellular respiration for all complex life. Oxygen is toxic to obligately anaerobic organisms, which were the dominant form of early life on Earth until O2 began to accumulate in the atmosphere 2.5 billion years ago. Another form (allotrope) of oxygen, ozone (O3), helps protect the biosphere from ultraviolet radiation with the high-altitude ozone layer, but is a pollutant near the surface where it is a by-product of smog. At even higher low earth orbit altitudes monatomic oxygen (O1) is a significant presence and a cause of erosion for spacecraft.

Oxygen was independently discovered by Carl Wilhelm Scheele, in Uppsala, in 1773 or earlier, and Joseph Priestley in Wiltshire, in 1774, but Priestley is often given priority because his publication came out in print first. The name oxygen was coined in 1777 by Antoine Lavoisier, whose experiments with oxygen helped to discredit the then-popular phlogiston theory of combustion and corrosion. Oxygen is produced industrially by fractional distillation of liquefied air, use of zeolites to remove carbon dioxide and nitrogen from air, electrolysis of water and other means. Uses of oxygen include the production of steel, plastics and textiles; rocket propellant; oxygen therapy; and life support in aircraft, submarines, spaceflight and diving.

This text uses material from Wikipedia, licensed under CC BY-SA