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Chromium is mined as chromite ( FeCr < sub > 2 </ sub > O < sub > 4 </ sub >) ore. About two-fifths of the chromite ores and concentrates in the world are produced in South Africa, while Kazakhstan, India, Russia, and Turkey are also substantial producers.
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Chromium and is
Chromium ( ) is a chemical element which has the symbol Cr and atomic number 24.
Chromium is remarkable for its magnetic properties: it is the only elemental solid which shows antiferromagnetic ordering at room temperature ( and below ).
Chromium metal left standing in air is passivated by oxygen, forming a thin protective oxide surface layer.
Chromium is the 24th most abundant element in Earth's crust with an average concentration of 100 ppm.
Chromium deficiency is controversial or is at least extremely rare.
A beta version of this plugin is also available for Google Chrome and Chromium.
Stainless steel is defined as a regular steel alloy with greater than 10 % by weight alloying content of Chromium.
Chromium impurities in corundum yield a red tint, and the resultant gemstone is called a ruby.
For example, one species of chromium, known as Chromium III or Trivalent Chromium, is needed by the body and causes no ill effects ; however, Chromium VI or Hexavalent Chromium, is very toxic to the body.
Chromium iron is a commonly used material, which gives an efficiency of about 1 % over a wide range of energies.
Chromium is added in small amounts to the ladle to reduce free graphite, produce chill, and because it is a powerful carbide stabilizer ; nickel is often added in conjunction.
The difference is consistent with cross-linking by polychromium species, of the sort arising from olation and oxolation. Possible Chromium ( III ) Tanning Mechanisms
In acid solution the unstable blue peroxo complex Chromium ( VI ) oxide peroxide, CrO ( O < sub > 2 </ sub >)< sub > 2 </ sub >, is formed ; it is an uncharged covalent molecule which may be extracted into ether.
Chromium and mined
Chromium, lead, and copper are mined.
Chromium likewise began to be mined and processed in the province.
Chromium and chromite
Chromium and ferrochromium are produced from the single commercially viable ore, chromite, by silicothermic or aluminothermic reaction or by roasting and leaching processes.
Chromium and <
Frimy and Auguste Verneuil manufactured artificial ruby by fusing BaF < sub > 2 </ sub > and Al < sub > 2 </ sub > O < sub > 3 </ sub > with a little Chromium at red heat.
Chromium ( III ) sulfate (< sub > 2 </ sub >( SO < sub > 4 </ sub >)< sub > 3 </ sub >) has long been regarded as the most efficient and effective tanning agent.
Chromium ( III ) sulfate dissolves to give the hexaaquachromium ( III ) cation, < sup > 3 +</ sup >, which at higher pH undergoes processes called olation to give polychromium ( III ) compounds that are active in tanning, being the cross-linking of the collagen subunits.
Chromium dioxide ( referred to as CrO < sub > 2 </ sub > or Type II ) was the first tape designed for extended high frequency response, but it required different bias and equalization settings.
< td align = center > Chromium ( III )</ td >
* Chromium trioxide, CrO < sub > 3 </ sub >
* Chromium ( III ) oxide, Cr < sub > 2 </ sub > O < sub > 3 </ sub >
* Chromium dioxide ( chromium ( IV ) oxide ), CrO < sub > 2 </ sub >
* Chromium trioxide ( chromium ( VI ) oxide ), CrO < sub > 3 </ sub >
* Chromium ( VI ) oxide peroxide, CrO < sub > 5 </ sub >
< td align =" center "> Chromium III ( Cr < sup > 3 +</ sup >)</ td >
Chromium and 2
Chromium oxide was used by the Chinese in the Qin dynasty over 2, 000 years ago to coat weapons such as bronze crossbow bolts and steel swords found at the Terracotta Army.
* Chromium ( II ) oxide, a metal oxide with Chromium in the + 2 oxidation state
Chromium ( IV )- doped YAG ( Cr: YAG ) provides a large absorption cross section in the 0. 9-1. 2 micrometer spectral region, which makes it an attractive choice as a passive Q-switch for Nd-doped lasers.
Chromium and .
Chromium analysis gave 58.8% Cr as compared with 61.2% theory.
Chromium was regarded with great interest because of its high corrosion resistance and hardness.
Chromium metal treated in this way readily dissolves in weak acids.
Chromium, unlike metals such as iron and nickel, does not suffer from hydrogen embrittlement.
Chromium compounds are found in the environment, due to erosion of chromium-containing rocks and can be distributed by volcanic eruptions.
Chromium isotopic contents are typically combined with manganese isotopic contents and have found application in isotope geology.
Chromium has no verified biological role and has been classified as not essential for mammals.
Chromium salts ( chromates ) are also the cause of allergic reactions in some people.
* ATSDR Case Studies in Environmental Medicine: Chromium Toxicity U. S. Department of Health and Human Services
Chromium, which had sold for $ 3. 90 a pound in 1980, was down to $ 3. 70 in 1990.
Other solutions support parallel OpenGL programs for Virtual Reality, scalability or graphics clusters usage, either transparently like Chromium or through a programming interface like Equalizer.
Chromium salts can also be used to impart moderate anti-stick properties.
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