Jean has perfect control over these flames, and they only consume what she wills, and these flames do not require oxygen to burn, and burn so intensely that matter is consumed without by-products such as ash.

As they form and flake off from the surface, fresh iron is exposed, and the corrosion process continues until either all of the iron is consumed or all of the oxygen, water, carbon dioxide, or sulfur dioxide in the system are removed or consumed.

Some hypotheses about the evolution of the human brain argue that it is a sexually selected trait, as it would not confer enough fitness in itself relative to its high maintenance costs ( a quarter to a fifth of the energy and oxygen consumed by a human ).< ref >

After the star has consumed the helium at the core, fusion continues in a shell around a hot core of carbon and oxygen.

In modern candles, the wick is constructed so that it curves over as it burns ( see picture on the right ), so that the end of the wick gets oxygen and is then consumed by fire — a self-trimming wick.

The oxidizer should contain at least 25 % oxygen, have high density, low heat of formation, and produce metal with low melting and high boiling point ( so the energy released is not consumed in evaporation of reaction products ).

Water and atmospheric oxygen also must be consumed in large quantities, but are not always considered " food " or " nutrients ".

The chemical elements consumed in the greatest quantities by plants are carbon, hydrogen, and oxygen.

In cases where the Japanese were installed in deep caves, the flames often consumed the available oxygen, suffocating the occupants.

Without sufficient oxygen to sustain life, people will act normally at first but will then abruptly feel dizzy and black out in a matter of seconds as the remaining oxygen in the blood stream is consumed.

The so-called 5-day BOD measures the amount of oxygen consumed by biochemical oxidation of waste contaminants in a 5-day period.

The total amount of oxygen consumed when the biochemical reaction is allowed to proceed to completion is called the Ultimate BOD.

Usually the brought-in oxygen is more than the oxygen consumed in burning glucose ( it is not yet settled whether most glucose consumption is oxidative ), and this causes a net decrease in dHb in that brain area's blood vessels.

The Fick principle was first described by Adolf Eugen Fick in 1870 and assumes that the rate at which oxygen is consumed is a function of the rate of blood flows and the rate of oxygen picked up by the red blood cells.

The Fick principle involves calculating the oxygen consumed over a given period of time from measurement of the oxygen concentration of the venous blood and the arterial blood.

There have also been modifications to the Fick method where respiratory oxygen content is measured as part of a closed system and the consumed Oxygen calculated using an assumed oxygen consumption index which is then used to calculate Q.

However, if the airways are patent ( open ), any gas supplied to the upper airways will follow the pressure gradient and flow into the lungs to replace the oxygen consumed.

When insufficient oxygen is available from the exhaust stream, the stored oxygen is released and consumed ( see cerium ( IV ) oxide ).

Following observation of the fact that the reaction rates of supposedly identical reaction mixtures prepared on the same filling manifold and exposed under identical conditions often differed by several hundred per cent, a systematic series of experiments was undertaken to see whether the difficulty could be ascribed to the method of preparing the chlorine, to the effects of oxygen or moisture or to the effect of surface to volume ratio in the reaction tubes.

Recent studies by Weston and Stack had indicated that a turbine aerator could be added to an oxidation pond to increase the rate of oxygen transfer.

The anaerobic conditions in the existing oxidation pond necessitated examination of other methods for supplying additional oxygen than by sodium nitrate.

The polyethylene cover reduced the oxygen transfer rate by 10 per cent, indicating that the maximum oxygen transfer is at the rotor rather than through the surface.

Spoilage by chemical action results from the reaction of one group of components in the food with others or with its environment, as in corrosion of the walls of metal containers or the reaction of fats with oxygen in the air to produce rancidity.

These balls are moving in great circles and ellipses, and are of course, the electrons, the particles of negative electricity which by their action create the forces that tie this atom of calcium to the neighboring atoms of oxygen and make up the solid structure of my finger bone.

For their purposes, oxygen and other gases were not drawn from the surrounding atmosphere through the medium of lungs but sustained artificially by solution in their shells.

Argon ( αργος, Greek meaning " inactive ", in reference to its chemical inactivity ) was suspected to be present in air by Henry Cavendish in 1785 but was not isolated until 1894 by Lord Rayleigh and Sir William Ramsay in Scotland in an experiment in which they removed all of the oxygen, carbon dioxide, water and nitrogen from a sample of clean air.

Argon is isolated from air by fractionation, most commonly by cryogenic fractional distillation, a process that also produces purified nitrogen, oxygen, neon, krypton and xenon.

* 1774 – British scientist Joseph Priestley discovered oxygen gas, corroborating the prior discovery of this element by German-Swedish chemist Carl Wilhelm Scheele.

In these compounds, at least one carbon atom is replaced by one of the heteroatoms oxygen, nitrogen, or sulfur.

Lavoisier also contributed to early ideas on composition and chemical changes by stating the radical theory, believing that radicals, which function as a single group in a chemical process, combine with oxygen in reactions.

Used to relieve both exertional and vasospastic angina by allowing venous pooling, reducing the pressure in the ventricles and so reducing wall tension and oxygen requirements in the heart.

Since Lavoisier's knowledge of strong acids was mainly restricted to oxoacids, such as ( nitric acid ) and ( sulphuric acid ), which tend to contain central atoms in high oxidation states surrounded by oxygen, and since he was not aware of the true composition of the hydrohalic acids ( HF, HCl, HBr, and HI ), he defined acids in terms of their containing oxygen, which in fact he named from Greek words meaning " acid-former " ( from the Greek οξυς ( oxys ) meaning " acid " or " sharp " and γεινομαι ( geinomai ) meaning " engender ").

The Lavoisier definition was held as absolute truth for over 30 years, until the 1810 article and subsequent lectures by Sir Humphry Davy in which he proved the lack of oxygen in H < sub > 2 </ sub > S, H < sub > 2 </ sub > Te, and the hydrohalic acids.

One notable modification of oxygen theory was provided by Berzelius, who stated that acids are oxides of nonmetals while bases are oxides of metals.

The most important oxidation reactions are with ozone, hydrogen peroxide and oxygen ( reactions with oxygen are catalyzed by iron and manganese in the cloud droplets ).

Antioxidant activity could be measured simply by placing the fat in a closed container with oxygen and measuring the rate of oxygen consumption.

Research into how vitamin E prevents the process of lipid peroxidation led to the identification of antioxidants as reducing agents that prevent oxidative reactions, often by scavenging reactive oxygen species before they can damage cells.

A helium-oxygen breathing gas is often used by deep-sea divers at depths of seawater over 55 m ( 180 ft ) to keep the diver from experiencing oxygen toxemia, the lethal effect of high-pressure oxygen, and nitrogen narcosis, the distracting narcotic effect of the nitrogen in air beyond this partial-pressure threshold.

* Rebreather scuba recycles the exhaled gas, removes carbon dioxide, and compensates for the used oxygen before the diver is supplied with gas from the breathing circuit.

This early rebreather design worked with an oxygen reservoir, the oxygen being delivered progressively by the diver himself and circulating in a closed circuit through a sponge soaked in limewater.

An oxygen rebreather diver or a fully closed circuit rebreather diver consumes about 1 litre of oxygen per minute.

So, a diver with a 3 litre oxygen cylinder filled to 200 bar who leaves 25 % in reserve will be able to do a 450 minute = 7. 5 hour dive ( 3 L × 200 bar × 0. 75 / 1 ).

In the real world they have to process a massive amount of water to extract enough oxygen to supply an active diver, and processing this much water takes a great deal of energy ( possible for cold-blooded fish, but harder for humans with higher metabolic rates ).

In technical diving, the diver may carry different equipment for different phases of the dive ; some breathing gas mixes may only be used at depth, such as trimix and others, such as pure oxygen, which only may be used during decompression stops in shallow water.

This early rebreather design worked with an oxygen reservoir, the oxygen being delivered progressively by the diver himself and circulating in a closed circuit through a sponge soaked in limewater.

As the diver goes deeper, much the same quantity of oxygen is used, which represents an increasingly smaller fraction of the inhaled gas.

This early rebreather design worked with an oxygen reservoir, the oxygen being delivered progressively by the diver and circulating in a closed circuit through a sponge soaked in limewater.

When that breath is exhaled back into the surrounding environment, it has an oxygen level in the range of 15 to 16 % when the diver is at atmospheric pressure.

The fully closed circuit rebreather is able to minimise the proportion of inert gases in the breathing mix, and therefore minimise the decompression requirements of the diver, by maintaining a specific and relatively high oxygen partial pressure ( ppO < sub > 2 </ sub >) at all depths.

Most modern rebreathers have a system of sensitive oxygen sensors, which allow the diver to adjust the partial pressure of oxygen.

This can offer a dramatic advantage at the end of deeper dives, where a diver can raise the partial pressure of oxygen somewhat at shallower depth, permitting shorter decompression times.

Many diver training organizations teach the " diluent flush " technique as a safe way to restore the mix in the loop to a level of oxygen that is neither too high nor too low.