Vanadium

Vanadium,  23V
General properties
Name, symbol vanadium, V
Pronunciation /vəˈndiəm/
və-NAY-dee-əm
Appearance blue-silver-grey metal
Vanadium in the periodic table


V

Nb
titaniumvanadiumchromium
Atomic number (Z) 23
Group, block group 5, d-block
Period period 4
Element category   transition metal
Standard atomic weight (±) (Ar) 50.9415(1)[1]
Electron configuration [Ar] 3d3 4s2
per shell
2, 8, 11, 2
Physical properties
Phase solid
Melting point 2183 K (1910 °C, 3470 °F)
Boiling point 3680 K (3407 °C, 6165 °F)
Density near r.t. 6.0 g/cm3
when liquid, at m.p. 5.5 g/cm3
Heat of fusion 21.5 kJ/mol
Heat of vaporization 444 kJ/mol
Molar heat capacity 24.89 J/(mol·K)

vapor pressure

P (Pa) 1 10 100 1 k 10 k 100 k
at T (K) 2101 2289 2523 2814 3187 3679
Atomic properties
Oxidation states 5, 4, 3, 2, 1, −1, −3 (an amphoteric oxide)
Electronegativity Pauling scale: 1.63
Ionization energies 1st: 650.9 kJ/mol
2nd: 1414 kJ/mol
3rd: 2830 kJ/mol
(more)
Atomic radius empirical: 134 pm
Covalent radius 153±8 pm
Miscellanea
Crystal structure

body-centered cubic (bcc)

Body-centered cubic crystal structure for vanadium
Speed of sound thin rod 4560 m/s (at 20 °C)
Thermal expansion 8.4 µm/(m·K) (at 25 °C)
Thermal conductivity 30.7 W/(m·K)
Electrical resistivity 197 nΩ·m (at 20 °C)
Magnetic ordering paramagnetic
Young's modulus 128 GPa
Shear modulus 47 GPa
Bulk modulus 160 GPa
Poisson ratio 0.37
Mohs hardness 6.7
Vickers hardness 628–640 MPa
Brinell hardness 600–742 MPa
CAS Number 7440-62-2
History
Discovery Andrés Manuel del Río (1801)
First isolation Nils Gabriel Sefström (1830)
Named by Nils Gabriel Sefström (1830)
Most stable isotopes of vanadium
iso NA half-life DM DE (MeV) DP
48V syn 15.9735 d β+ 4.0123 48Ti
49V syn 330 d ε 0.6019 49Ti
50V 0.25% 1.5×1017 y ε 2.2083 50Ti
β 1.0369 50Cr
51V 99.75% is stable with 28 neutrons

Vanadium is a chemical element with symbol V and atomic number 23. It is a hard, silvery grey, ductile, and malleable transition metal. The elemental metal is rarely found in nature, but once isolated artificially, the formation of an oxide layer (passivation) stabilizes the free metal somewhat against further oxidation.

Andrés Manuel del Río discovered compounds of vanadium in 1801 in Mexico by analyzing a new lead-bearing mineral he called "brown lead", and presumed its qualities were due to the presence of a new element, which he named erythronium (derived from Greek for "red") since, upon heating, most of the salts turned red. Four years later, however, he was (erroneously) convinced by other scientists that erythronium was identical to chromium. Chlorides of vanadium were generated in 1830 by Nils Gabriel Sefström who thereby proved that a new element was involved, which he named "vanadium" after the Scandinavian goddess of beauty and fertility, Vanadís (Freyja). Both names were attributed to the wide range of colors found in vanadium compounds. Del Rio's lead mineral was later renamed vanadinite for its vanadium content. In 1867 Henry Enfield Roscoe obtained the pure element.

Vanadium occurs naturally in about 65 different minerals and in fossil fuel deposits. It is produced in China and Russia from steel smelter slag; other countries produce it either from the flue dust of heavy oil, or as a byproduct of uranium mining. It is mainly used to produce specialty steel alloys such as high-speed tool steels. The most important industrial vanadium compound, vanadium pentoxide, is used as a catalyst for the production of sulfuric acid.

Large amounts of vanadium ions are found in a few organisms, possibly as a toxin. The oxide and some other salts of vanadium have moderate toxicity. Particularly in the ocean, vanadium is used by some life forms as an active center of enzymes, such as the vanadium bromoperoxidase of some ocean algae.

History

Vanadium was discovered by Andrés Manuel del Río, a Spanish-Mexican mineralogist, in 1801. Del Río extracted the element from a sample of Mexican "brown lead" ore, later named vanadinite. He found that its salts exhibit a wide variety of colors, and as a result he named the element panchromium (Greek: παγχρώμιο "all colors"). Later, Del Río renamed the element erythronium (Greek: ερυθρός "red") because most of the salts turned red upon heating. In 1805, the French chemist Hippolyte Victor Collet-Descotils, backed by del Río's friend Baron Alexander von Humboldt, incorrectly declared that del Río's new element was only an impure sample of chromium. Del Río accepted Collet-Descotils' statement and retracted his claim.[2]

In 1831, the Swedish chemist Nils Gabriel Sefström rediscovered the element in a new oxide he found while working with iron ores. Later that same year, Friedrich Wöhler confirmed del Río's earlier work.[3] Sefström chose a name beginning with V, which had not been assigned to any element yet. He called the element vanadium after Old Norse Vanadís (another name for the Norse Vanr goddess Freyja, whose attributes include beauty and fertility), because of the many beautifully colored chemical compounds it produces.[3] In 1831, the geologist George William Featherstonhaugh suggested that vanadium should be renamed "rionium" after del Río, but this suggestion was not followed.[4]

The Model T made use of vanadium steel in its chassis.

The isolation of vanadium metal proved difficult. In 1831, Berzelius reported the production of the metal, but Henry Enfield Roscoe showed that Berzelius had in fact produced the nitride, vanadium nitride (VN). Roscoe eventually produced the metal in 1867 by reduction of vanadium(II) chloride, VCl2, with hydrogen.[5] In 1927, pure vanadium was produced by reducing vanadium pentoxide with calcium.[6]

The first large-scale industrial use of vanadium was in the steel alloy chassis of the Ford Model T, inspired by French race cars. Vanadium steel allowed for reduced weight while simultaneously increasing tensile strength (ca. 1905).[7]

German chemist Martin Henze discovered vanadium in the blood cells (or coelomic cells) of Ascidiacea (sea squirts) in 1911.[8][9]

Characteristics

High-purity (99.95%) vanadium cuboids, ebeam remelted and macro-etched

Vanadium is a medium-hard, ductile, steel-blue metal. Some sources describe vanadium as "soft", perhaps because it is ductile, malleable and not brittle.[10][11] Vanadium is harder than most metals and steels (see Hardnesses of the elements (data page) and iron). It has good resistance to corrosion and it is stable against alkalis and sulfuric and hydrochloric acids.[12] It is oxidized in air at about 933 K (660 °C, 1220 °F), although an oxide passivation layer forms even at room temperature.

Isotopes

Main article: Isotopes of vanadium

Naturally occurring vanadium is composed of one stable isotope, 51V, and one radioactive isotope, 50V. The latter has a half-life of 1.5×1017 years and a natural abundance of 0.25%. 51V has a nuclear spin of 7/2, which is useful for NMR spectroscopy.[13] Twenty-four artificial radioisotopes have been characterized, ranging in mass number from 40 to 65. The most stable of these isotopes are 49V with a half-life of 330 days, and 48V with a half-life of 16.0 days. The remaining radioactive isotopes have half-lives shorter than an hour, most below 10 seconds. At least four isotopes have metastable excited states.[13] Electron capture is the main decay mode for isotopes lighter than 51V. For the heavier ones, the most common mode is beta decay. The electron capture reactions lead to the formation of element 22 (titanium) isotopes, while beta decay leads to element 24 (chromium) isotopes.

Chemistry

From left: [V(H2O)6]2+ (lilac), [V(H2O)6]3+ (green), [VO(H2O)5]2+ (blue) and [VO(H2O)5]3+ (yellow).

The chemistry of vanadium is noteworthy for the accessibility of the four adjacent oxidation states 2-5. In aqueous solution, vanadium forms metal aquo complexes of which the colours are lilac [V(H2O)6]2+, green [V(H2O)6]3+, blue [VO(H2O)5]2+, yellow VO3. Vanadium(II) compounds are reducing agents, and vanadium(V) compounds are oxidizing agents. Vanadium(IV) compounds often exist as vanadyl derivatives, which contain the VO2+ center.[12]

Ammonium vanadate(V) (NH4VO3) can be successively reduced with elemental zinc to obtain the different colors of vanadium in these four oxidation states. Lower oxidation states occur in compounds such as V(CO)6, [V(CO)
6
]
and substituted derivatives.[12]

The most commercially important compound is vanadium pentoxide. It is used as a catalyst for the production of sulfuric acid.[12] This compound oxidizes sulfur dioxide (SO
2
) to the trioxide (SO
3
). In this redox reaction, sulfur is oxidized from +4 to +6, and vanadium is reduced from +5 to +4:

V2O5 + SO2 → 2 VO2 + SO3

The catalyst is regenerated by oxidation with air:

2 VO2 + O2 → V2O5

Similar oxidations are used in the production of maleic anhydride, phthalic anhydride, and several other bulk organic compounds.[14]

The vanadium redox battery utilizes all four oxidation states; one electrode uses the +5/+4 couple and the other uses the +3/+2 couple. Conversion of these oxidation states is illustrated by the reduction of a strongly acidic solution of a vanadium(V) compound with zinc dust or amalgam. The initial yellow color characteristic of the pervanadyl ion [VO2(H2O)4]+ is replaced by the blue color of [VO(H2O)5]2+, followed by the green color of [V(H2O)6]3+ and then the violet color of [V(H2O)6]2+.[12]

Oxyanions

The decavanadate structure

In aqueous solution, vanadium(V) forms an extensive family of oxyanions. The interrelationships in this family are described by the predominance diagram, which shows at least 11 species, depending on pH and concentration.[15] The tetrahedral orthovanadate ion, VO3−
4
, is the principal species present at pH 12-14. Similar in size and charge to phosphorus(V), vanadium(V) also parallels its chemistry and crystallography. Orthovanadate VO3−
4
is used in protein crystallography[16] to study the biochemistry of phosphate.[17] The tetrathiovanadate [VS4]3− is analogous to the orthovanadate ion.[18]

At lower pH's, the monomer [HVO4]2− and dimer [V2O7] are formed, with the monomer predominant at vanadium concentration of less than c. 10−2M (pV > 2, where pV is equal to the minus value of the logarithm of the total vanadium concentration/M). The formation of the divanadate ion is analogous to the formation of the dichromate ion. As the pH is reduced, further protonation and condensation to polyvanadates occur: at pH 4-6 [H2VO4] is predominant at pV greater than ca. 4, while at higher concentrations trimers and tetramers are formed. Between pH 2-4 decavanadate predominates, its formation from orthovanadate is represented by this condensation reaction:

10 [VO4]3− + 24 H+ → [V10O28]6− + 12 H2O

In decavanadate, each V(V) center is surrounded by six oxide ligands.[12] Vanadic acid, H3VO4 exists only a very low concentrations because protonation of the tetrahedral species [H2VO4] results in the preferential formation of the octahedral [VO2(H2O)4]+ species. In strongly acidic solutions, pH<2. [VO2(H2O)4]+ is the predominant species, while the oxide V2O5 precipitates from solution at high concentrations. The oxide is formally the inorganic anhydride of vanadic acid. The structures of many vanadate compounds have been determined by X-ray crystallography.

The Pourbaix diagram for vanadium in water

The Pourbaix diagram for vanadium in water, which shows the redox potentials between various vanadium species in different oxidation states, is also complex.[19]

Vanadium(V) forms various peroxo complexes, most notably in the active site of the vanadium-containing bromoperoxidase enzymes. The species VO(O)2(H2O)4+ is stable in acidic solutions. In alkaline solutions, species with 2, 3 and 4 peroxide groups are known; the last forms violet salts with the formula M3V(O2)4 nH2O (M = Li, Na, etc.), in which the vanadium has an 8-coordinate dodecahedral structure.[20][21]

Halide derivatives

Twelve binary halides, compounds with the formula VXn (n=2..5), are known. VI4, VCl5, VBr5, and VI5 do not exist or are extremely unstable. In combination with other reagents, VCl4 is used as a catalyst for polymerization of dienes. Like all binary halides, those of vanadium are Lewis acidic, especially those of V(IV) and V(V). Many of the halides form octahedral complexes with the formula VXnL6−n (X = halide; L = other ligand).

Many vanadium oxyhalides (formula VOmXn) are known.[22] The oxytrichloride and oxytrifluoride (VOCl3 and VOF3) are the most widely studied. Akin to POCl3, they are volatile, adopt tetrahedral structures in the gas phase, and are Lewis acidic.

Coordination compounds

A ball-and-stick model of VO5(C5H7)2

Complexes of vanadium(II) and (III) are relatively exchange inert and reducing. Those of V(IV) and V(V) are oxidants. Vanadium ion is rather large and some complexes achieve coordination numbers greater than 6, as is the case in [V(CN)7]4−. Oxovanadium(V) also forms 7 coordinate coordination complexes with tetradentate ligands and peroxides and these complexes are used for oxidative brominations and thioether oxidations. The coordination chemistry of V4+ is dominated by the vanadyl center, VO2+, which binds four other ligands strongly and one weakly (the one trans to the vanadyl center). An example is vanadyl acetylacetonate (V(O)(O2C5H7)2). In this complex, the vanadium is 5-coordinate, square pyramidal, meaning that a sixth ligand, such as pyridine, may be attached, though the association constant of this process is small. Many 5-coordinate vanadyl complexes have a trigonal bypyramidal geometry, such as VOCl2(NMe3)2.[23] The coordination chemistry of V5+ is dominated by the relatively stable dioxovanadium coordination complexes which are often formed by aerial oxidation of the vanadium(IV) precursors indicating the stability of the +5 oxidation state and ease of interconversion between the +4 and +5 states.

Organometallic compounds

Organometallic chemistry of vanadium is well developed, although they are mainly only academic significance. Vanadocene dichloride is a versatile starting reagent and even finds some applications in organic chemistry.[24] Vanadium carbonyl, V(CO)6, is a rare example of a paramagnetic metal carbonyl. Reduction yields V(CO)
6
(isoelectronic with Cr(CO)6), which may be further reduced with sodium in liquid ammonia to yield V(CO)3−
5
(isoelectronic with Fe(CO)5).[25][26]

Occurrence

Universe

The cosmic abundance of vanadium in the universe is 0.0001%, making the element nearly as common as copper or zinc.[27] Vanadium is detected spectroscopically in light from the Sun and sometimes in the light from other stars.[28]

Earth's crust

Vanadium is the 22nd most abundant element in the earth's crust;[27] metallic vanadium is rare in nature (known as the mineral vanadium, native vanadium),[29][30] but vanadium compounds occur naturally in about 65 different minerals. Economically significant examples include patronite (VS4),[31] vanadinite (Pb5(VO4)3Cl), and carnotite (K2(UO2)2(VO4)2·3H2O). Much of the world's vanadium production is sourced from vanadium-bearing magnetite found in ultramafic gabbro bodies. Vanadium is mined mostly in South Africa, north-western China, and eastern Russia. In 2013 these three countries mined more than 97% of the 79,000 tonnes of produced vanadium.[32]

Vanadium is also present in bauxite and in deposits of crude oil, coal, oil shale and tar sands. In crude oil, concentrations up to 1200 ppm have been reported. When such oil products are burned, traces of vanadium may cause corrosion in engines and boilers.[33] An estimated 110,000 tonnes of vanadium per year are released into the atmosphere by burning fossil fuels.[34]

Water

The vanadyl ion is abundant in seawater, having an average concentration of 30 nM.[27] Some mineral water springs also contain the ion in high concentrations. For example, springs near Mount Fuji contain as much as 54 μg per liter.[27]

Production

Ferrovanadium chunks
Vacuum sublimed vanadium dendritic crystals (99.9%)
Crystal-bar vanadium, showing different textures and surface oxidation; 3N5-pure cube for comparison

Most vanadium is used as a steel alloy called ferrovanadium. Ferrovanadium is produced directly by reducing a mixture of vanadium oxide, iron oxides and iron in an electric furnace. The vanadium ends up in pig iron produced from vanadium-bearing magnetite. Depending on the ore used, the slag contains up to 25% of vanadium.[35]

Vanadium metal is obtained by a multistep process that begins with the roasting of crushed ore with NaCl or Na2CO3 at about 850 °C to give sodium metavanadate (NaVO3). An aqueous extract of this solid is acidified to give "red cake", a polyvanadate salt, which is reduced with calcium metal. As an alternative for small-scale production, vanadium pentoxide is reduced with hydrogen or magnesium. Many other methods are also in use, in all of which vanadium is produced as a byproduct of other processes.[35] Purification of vanadium is possible by the crystal bar process developed by Anton Eduard van Arkel and Jan Hendrik de Boer in 1925. It involves the formation of the metal iodide, in this example vanadium(III) iodide, and the subsequent decomposition to yield pure metal.[36]

2 V + 3 I2 2 VI3

Applications

Tool made from vanadium steel

Alloys

Approximately 85% of vanadium produced is used as ferrovanadium or as a steel additive.[35] The considerable increase of strength in steel containing small amounts of vanadium was discovered in the early 20th century. Vanadium forms stable nitrides and carbides, resulting in a significant increase in the strength of steel.[37] From that time on, vanadium steel was used for applications in axles, bicycle frames, crankshafts, gears, and other critical components. There are two groups of vanadium steel alloys. Vanadium high-carbon steel alloys contain 0.15% to 0.25% vanadium, and high-speed tool steels (HSS) have a vanadium content of 1% to 5%. For high-speed tool steels, a hardness above HRC 60 can be achieved. HSS steel is used in surgical instruments and tools.[38] Powder-metallurgic alloys contain up to 18% percent vanadium. The high content of vanadium carbides in those alloys increases wear resistance significantly. One application for those alloys is tools and knives.[39]

Vanadium stabilizes the beta form of titanium and increases the strength and temperature stability of titanium. Mixed with aluminium in titanium alloys, it is used in jet engines, high-speed airframes and dental implants. The most common alloy for seamless tubing is Titanium 3/2.5, the titanium alloy of choice in the aerospace, defense and bicycle industries.[40] Another common alloy, primarily produced in sheets, is Titanium 6AL-4V, a titanium alloy with 6% aluminium and 4% vanadium.[41]

Several vanadium alloys show superconducting behavior. The first A15 phase superconductor was a vanadium compound, V3Si, which was discovered in 1952.[42] Vanadium-gallium tape is used in superconducting magnets (17.5 teslas or 175,000 gauss). The structure of the superconducting A15 phase of V3Ga is similar to that of the more common Nb3Sn and Nb3Ti.[43]

It has been proposed that a small amount, 40 to 270 ppm, of vanadium in Wootz steel and Damascus steel significantly improved the strength of the product, though the source of the vanadium is unclear.[44]

Other uses

Vanadium(V) oxide is a catalyst in the contact process for producing sulfuric acid

Vanadium foil is used in cladding titanium to steel because it is compatible with both iron and titanium.[45] The moderate thermal neutron-capture cross-section and the short half-life of the isotopes produced by neutron capture makes vanadium a suitable material for the inner structure of a fusion reactor.[46][47]

The most common oxide of vanadium, vanadium pentoxide V2O5, is used as a catalyst in manufacturing sulfuric acid by the contact process[48] and as an oxidizer in maleic anhydride production.[49] Vanadium pentoxide is used in ceramics.[50] Vanadium is an important component of mixed metal oxide catalysts used in the oxidation of propane and propylene to acrolein, acrylic acid or the ammoxidation of propylene to acrylonitrile.[51][52][53] In service, the oxidation state of vanadium changes dynamically and reversibly with the oxygen and the steam content of the reacting feed mixture.[54][55] Another oxide of vanadium, vanadium dioxide VO2, is used in the production of glass coatings, which blocks infrared radiation (and not visible light) at a specific temperature.[56] Vanadium oxide can be used to induce color centers in corundum to create simulated alexandrite jewelry, although alexandrite in nature is a chrysoberyl.[57]

The Vanadium redox battery, a type of flow battery, is an electrochemical cell consisting of aqueous vanadium ions in different oxidation states.[58][59] Batteries of the type were first proposed in the 1930s and developed commercially from the 1980s onwards. Cells use +5 and +2 formal oxidization state ions, and (as of 2016) are used commercially for small scale (c. 0.1 - 10 MW, 0.1 - 100 GJ) grid energy storage.

Vanadate can be used for protecting steel against rust and corrosion by conversion coating.[60]

Proposed

Lithium vanadium oxide has been proposed for use as a high energy density anode for lithium ion batteries, at 745 Wh/L when paired with a lithium cobalt oxide cathode.[61] Vanadium phosphates have been proposed as the cathode in the Lithium Vanadium Phosphate Battery, another type of lithium ion battery.

Biological role

Vanadium plays a limited role in human biology.[62] It is more important in marine environments than terrestrial.[63]

Active site of the enzyme vanadium bromoperoxidase, which produces the preponderance of naturally-occurring organobromine compounds.
Tunicates such as this bluebell tunicate contain vanadium as vanabin.

Vanadoenzymes

A number of species of marine algae produce vanadium bromoperoxidase as well as the closely related chloroperoxidase (which may use a heme or vanadium cofactor) and iodoperoxidases. The bromoperoxidase produces an estimated 1–2 million tons of bromoform and 56,000 tons of bromomethane annually.[64] Most naturally occurring organobromine compounds are produced by this enzyme,[65] catalyzing the following reaction (R-H is hydrocarbon substrate):

R-H + Br + H2O2 → R-Br + H2O + OH

A vanadium nitrogenase is used by some nitrogen-fixing micro-organisms, such as Azotobacter. In this role, vanadium replaces more common molybdenum or iron, and gives the nitrogenase slightly different properties.[66]

Vanadium accumulation in tunicates and ascidians

Vanadium is essential to ascidians and tunicates, where it is stored in the highly acidified vacuoles of certain blood cell types, designated "vanadocytes". Vanabins (vanadium binding proteins) have been identified in the cytoplasm of such cells. The concentration of vanadium in the blood of ascidians is as much as ten million times higher[67][68] than the surrounding seawater, which normally contains 1 to 2 µg/l.[69][70] The function of this vanadium concentration system and these vanadium-bearing proteins is still unknown, but the vanadocytes are later deposited just under the outer surface of the tunic where they may deter predation.[71]

Fungi

Amanita muscaria and related species of macrofungi accumulate vanadium (up to 500 mg/kg in dry weight). Vanadium is present in the coordination complex amavadin[72] in fungal fruit-bodies. The biological importance of the accumulation is unknown.[73][74] Toxic or peroxidase enzyme functions have been suggested.

Mammals and birds

Deficiencies in vanadium result in reduced growth and impaired reproduction in rats and chickens.[75] Vanadium is a relatively controversial dietary supplement, used primarily for increasing insulin sensitivity[76] and body-building. Whether it works for the latter purpose has not been proven; some evidence suggests that athletes who take it are merely experiencing a placebo effect.[77] Vanadyl sulfate may improve glucose control in people with type 2 diabetes.[78][79][80][81][82] Decavanadate and oxovanadates appear to play a role in a variety of biochemical processes, such as those relating to oxidative stress.[83]

Safety

All vanadium compounds should be considered toxic. Tetravalent VOSO4 has been reported to be at least 5 times more toxic than trivalent V2O3.[84] The Occupational Safety and Health Administration (OSHA) has set an exposure limit of 0.05 mg/m3 for vanadium pentoxide dust and 0.1 mg/m3 for vanadium pentoxide fumes in workplace air for an 8-hour workday, 40-hour work week.[85] The National Institute for Occupational Safety and Health (NIOSH) has recommended that 35 mg/m3 of vanadium be considered immediately dangerous to life and health, that is, likely to cause permanent health problems or death.[85]

Vanadium compounds are poorly absorbed through the gastrointestinal system. Inhalation of vanadium and vanadium compounds results primarily in adverse effects on the respiratory system.[86][87][88] Quantitative data are, however, insufficient to derive a subchronic or chronic inhalation reference dose. Other effects have been reported after oral or inhalation exposures on blood parameters,[89][90] liver,[91] neurological development,[92] and other organs[93] in rats.

There is little evidence that vanadium or vanadium compounds are reproductive toxins or teratogens. Vanadium pentoxide was reported to be carcinogenic in male rats and in male and female mice by inhalation in an NTP study,[87] although the interpretation of the results has recently been disputed.[94] The carcinogenicity of vanadium has not been determined by the United States Environmental Protection Agency.[95]

Vanadium traces in diesel fuels are the main fuel component in high temperature corrosion. During combustion, vanadium oxidizes and reacts with sodium and sulfur, yielding vanadate compounds with melting points as low as 530 °C, which attack the passivation layer on steel and render it susceptible to corrosion. The solid vanadium compounds also abrade engine components.[96][97]

See also

References

  1. Standard Atomic Weights 2013. Commission on Isotopic Abundances and Atomic Weights
  2. Cintas, Pedro (2004). "The Road to Chemical Names and Eponyms: Discovery, Priority, and Credit". Angewandte Chemie International Edition. 43 (44): 5888–94. doi:10.1002/anie.200330074. PMID 15376297.
  3. 1 2 Sefström, N. G. (1831). "Ueber das Vanadin, ein neues Metall, gefunden im Stangeneisen von Eckersholm, einer Eisenhütte, die ihr Erz von Taberg in Småland bezieht". Annalen der Physik und Chemie. 97: 43–49. Bibcode:1831AnP....97...43S. doi:10.1002/andp.18310970103.
  4. Featherstonhaugh, George William (1831). "New Metal, provisionally called Vanadium". The Monthly American Journal of Geology and Natural Science: 69.
  5. Roscoe, Henry E. (1869–1870). "Researches on Vanadium. Part II". Proceedings of the Royal Society of London. 18 (114–122): 37–42. doi:10.1098/rspl.1869.0012.
  6. Marden, J. W.; Rich, M. N. (1927). "Vanadium". Industrial and Engineering Chemistry. 19 (7): 786–788. doi:10.1021/ie50211a012.
  7. Betz, Frederick (2003). Managing Technological Innovation: Competitive Advantage from Change. Wiley-IEEE. pp. 158–159. ISBN 0-471-22563-0.
  8. Henze, M (1911). "Untersuchungen fiber das Blut der Ascidien. I. Mitteilung". Z. Physiol. Chem. 72 (5–6): 494–50. doi:10.1515/bchm2.1911.72.5-6.494.
  9. Michibata, H; Uyama, T; Ueki, T; Kanamori, K (2002). "Vanadocytes, cells hold the key to resolving the highly selective accumulation and reduction of vanadium in ascidians". Microscopy Research and Technique. 56 (6): 421–434. doi:10.1002/jemt.10042. PMID 11921344.
  10. George F. Vander Voort (1984). Metallography, principles and practice. ASM International. pp. 137–. ISBN 978-0-87170-672-0. Retrieved 17 September 2011.
  11. François Cardarelli (2008). Materials handbook: a concise desktop reference. Springer. pp. 338–. ISBN 978-1-84628-668-1. Retrieved 17 September 2011.
  12. 1 2 3 4 5 6 Holleman, Arnold F.; Wiberg, Egon; Wiberg, Nils (1985). "Vanadium". Lehrbuch der Anorganischen Chemie (in German) (91–100 ed.). Walter de Gruyter. pp. 1071–1075. ISBN 3-11-007511-3.
  13. 1 2 Georges, Audi; Bersillon, O.; Blachot, J.; Wapstra, A.H. (2003). "The NUBASE Evaluation of Nuclear and Decay Properties". Nuclear Physics A. Atomic Mass Data Center. 729: 3–128. Bibcode:2003NuPhA.729....3A. doi:10.1016/j.nuclphysa.2003.11.001.
  14. Günter Bauer, Volker Güther, Hans Hess, Andreas Otto, Oskar Roidl, Heinz Roller, Siegfried Sattelberger "Vanadium and Vanadium Compounds" in Ullmann's Encyclopedia of Industrial Chemistry, 2005, Wiley-VCH, Weinheim. doi:10.1002/14356007.a27_367
  15. Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 984. ISBN 0-08-037941-9.
  16. Sinning, Irmgard; Hol, Wim G.J. (2004). "The power of vanadate in crystallographic investigations of phosphoryl transfer enzymes". FEBS Letters. 577 (3): 315–21. doi:10.1016/j.febslet.2004.10.022. PMID 15556602.
  17. Seargeant, Lorne E.; Stinson, Robert A. (1979). "Inhibition of human alkaline phosphatases by vanadate". Biochemical Journal. 181 (1): 247–50. PMC 1161148Freely accessible. PMID 486156.
  18. Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 988. ISBN 0-08-037941-9.
  19. Al-Kharafi, F. M.; Badawy, W. A. (1997). "Electrochemical behavior of vanadium in aqueous solutions of different pH". Electrochimica Acta. 42 (4): 579–586. doi:10.1016/S0013-4686(96)00202-2.
  20. Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 0-08-037941-9., p994.
  21. Strukul, Giorgio (1992). Catalytic oxidations with hydrogen peroxide as oxidant. Springer. p. 128. ISBN 0-7923-1771-8.
  22. Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. p. 993. ISBN 0-08-037941-9.
  23. Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 0-08-037941-9.
  24. Wilkinson, G. & Birmingham, J.G. (1954). "Bis-cyclopentadienyl Compounds of Ti, Zr, V, Nb and Ta". Journal of the American Chemical Society. 76 (17): 4281–4284. doi:10.1021/ja01646a008.
  25. Bellard, S.; Rubinson, K. A.; Sheldrick, G. M. (1979). "Crystal and molecular structure of vanadium hexacarbonyl". Acta Crystallographica. B35 (2): 271–274. doi:10.1107/S0567740879003332.
  26. Elschenbroich, C.; Salzer A. (1992). Organometallics : A Concise Introduction. Wiley-VCH. ISBN 3-527-28165-7.
  27. 1 2 3 4 Rehder, Dieter (2008). Bioinorganic Vanadium Chemistry (1st ed.). Hamburg, Germany: John Wiley & Sons, Ltd. pp. 5 & 9–10. doi:10.1002/9780470994429. ISBN 9780470065099.
  28. Cowley, C. R.; Elste, G. H.; Urbanski, J. L. (1978). "Vanadium abundances in early A stars". Publications of the Astronomical Society of the Pacific. 90: 536. Bibcode:1978PASP...90..536C. doi:10.1086/130379.
  29. Ostrooumov, M., and Taran, Y., 2015. Discovery of Native Vanadium, a New Mineral from the Colima Volcano, State of Colima (Mexico). Revista de la Sociedad Española de Mineralogía 20, 109-110
  30. "Vanadium: Vanadium mineral information and data". Mindat.org. Retrieved 2016-03-02.
  31. "mineralogical data about Patrónite". mindata.org. Retrieved 19 January 2009.
  32. Magyar, Michael J. "Mineral Commodity Summaries 2015: Vanadium" (PDF). United States Geological Survey. Retrieved 3 June 2015.
  33. Pearson, C. D.; Green J. B. (1993). "Vanadium and nickel complexes in petroleum resid acid, base, and neutral fractions". Energy Fuels. 7 (3): 338–346. doi:10.1021/ef00039a001.
  34. Anke, Manfred (2004). "Vanadium – An element both essential and toxic to plants, animals and humans?". Anal. Real Acad. Nac. Farm. 70: 961.
  35. 1 2 3 Moskalyk, R. R.; Alfantazi, A. M. (2003). "Processing of vanadium: a review". Minerals Engineering. 16 (9): 793–805. doi:10.1016/S0892-6875(03)00213-9.
  36. Carlson, O. N.; Owen, C. V. (1961). "Preparation of High-Purity Vanadium Metals by the Iodide Refining Process". Journal of the Electrochemical Society. 108: 88. doi:10.1149/1.2428019.
  37. Chandler, Harry (1998). Metallurgy for the Non-metallurgist. ASM International. pp. 6–7. ISBN 978-0-87170-652-2.
  38. Davis, Joseph R. (1995). Tool Materials: Tool Materials. ASM International. ISBN 978-0-87170-545-7.
  39. Oleg D. Neikov; Stanislav Naboychenko; Irina Mourachova; Victor G. Gopienko; Irina V. Frishberg; Dina V. Lotsko (2009-02-24). Handbook of Non-Ferrous Metal Powders: Technologies and Applications. p. 490. ISBN 9780080559407. Retrieved 17 October 2013.
  40. "Technical Supplement: Titanium". Seven Cycles. Retrieved 1 November 2016.
  41. Peters, Manfred; Leyens, C. (2002). "Metastabile β-Legierungen". Titan und Titanlegierungen. Wiley-VCH. pp. 23–24. ISBN 978-3-527-30539-1.
  42. Hardy, George F.; Hulm, John K. (1953). "Superconducting Silicides and Germanides". Physical Review. 89 (4): 884–884. Bibcode:1953PhRv...89Q.884H. doi:10.1103/PhysRev.89.884.
  43. Markiewicz, W.; Mains, E.; Vankeuren, R.; Wilcox, R.; Rosner, C.; Inoue, H.; Hayashi, C.; Tachikawa, K. (1977). "A 17.5 Tesla superconducting concentric Nb3Sn and V3Ga magnet system". IEEE Transactions on Magnetics. 13 (1): 35–37. Bibcode:1977ITM....13...35M. doi:10.1109/TMAG.1977.1059431.
  44. Verhoeven, J. D.; Pendray, A. H.; Dauksch, W. E. (1998). "The key role of impurities in ancient damascus steel blades". Journal of the Minerals, Metals and Materials Society. 50 (9): 58–64. Bibcode:1998JOM....50i..58V. doi:10.1007/s11837-998-0419-y.
  45. Lositskii, N. T.; Grigor'ev A. A.; Khitrova, G. V. (1966). "Welding of chemical equipment made from two-layer sheet with titanium protective layer (review of foreign literature)". Chemical and Petroleum Engineering. 2 (12): 854–856. doi:10.1007/BF01146317.
  46. Matsui, H.; Fukumoto, K.; Smith, D. L.; Chung, Hee M.; Witzenburg, W. van; Votinov, S. N. (1996). "Status of vanadium alloys for fusion reactors". Journal of Nuclear Materials. 233–237 (1): 92–99. Bibcode:1996JNuM..233...92M. doi:10.1016/S0022-3115(96)00331-5.
  47. "Vanadium Data Sheet" (PDF). ATI Wah Chang. Archived from the original (PDF) on 25 February 2009. Retrieved 16 January 2009.
  48. Eriksen, K. M.; Karydis, D. A.; Boghosian, S.; Fehrmann, R. (1995). "Deactivation and Compound Formation in Sulfuric-Acid Catalysts and Model Systems". Journal of Catalysis. 155 (1): 32–42. doi:10.1006/jcat.1995.1185.
  49. Abon, Michel; Volta, Jean-Claude (1997). "Vanadium phosphorus oxides for n-butane oxidation to maleic anhydride". Applied Catalysis A: General. 157 (1–2): 173–193. doi:10.1016/S0926-860X(97)00016-1.
  50. Lide, David R. (2004). "vanadium". CRC Handbook of Chemistry and Physics. Boca Raton: CRC Press. pp. 4–34. ISBN 978-0-8493-0485-9.
  51. Fierro, J. G. L. (ed.) (2006). Metal Oxides, Chemistry and Applications. CRC Press. pp. 415–455.
  52. "Kinetic studies of propane oxidation on Mo and V based mixed oxide catalysts. PhD Thesis". Technische Universität, Berlin, 2011.
  53. Amakawa, Kazuhiko; Kolen’ko, Yury V.; Villa, Alberto; Schuster, Manfred E/; Csepei, Lénárd-István; Weinberg, Gisela; Wrabetz, Sabine; d’Alnoncourt, Raoul Naumann; Girgsdies, Frank; Prati, Laura; Schlögl, Robert; Trunschke, Annette. "Multifunctionality of Crystalline MoV(TeNb) M1 Oxide Catalysts in Selective Oxidation of Propane and Benzyl Alcohol". ACS Catalysis. 3 (6): 1103–1113. doi:10.1021/cs400010q.
  54. Hävecker, Michael; Wrabetz, Sabine; Kröhnert, Jutta; Csepei, Lenard-Istvan; Naumann d’Alnoncourt, Raoul; Kolen’ko, Yury V.; Girgsdies, Frank; Schlögl, Robert; Trunschke, Annette (January 2012). "Surface chemistry of phase-pure M1 MoVTeNb oxide during operation in selective oxidation of propane to acrylic acid". Journal of Catalysis. 285 (1): 48–60. doi:10.1016/j.jcat.2011.09.012.
  55. Naumann d’Alnoncourt, Raoul; Csepei, Lénárd-István; Hävecker, Michael; Girgsdies, Frank; Schuster, Manfred E.; Schlögl, Robert; Trunschke, Annette (March 2014). "The reaction network in propane oxidation over phase-pure MoVTeNb M1 oxide catalysts". Journal of Catalysis. 311: 369–385. doi:10.1016/j.jcat.2013.12.008.
  56. Manning, Troy D.; Parkin, Ivan P.; Clark, Robin J. H.; Sheel, David; Pemble, Martyn E.; Vernadou, Dimitra (2002). "Intelligent window coatings: atmospheric pressure chemical vapour deposition of vanadium oxides". Journal of Materials Chemistry. 12 (10): 2936–2939. doi:10.1039/b205427m.
  57. White, Willam B.; Roy, Rustum; McKay, Chrichton (1962). "The Alexandrite Effect: And Optical Study" (PDF). American Mineralogist. 52: 867–871.
  58. Joerissen, Ludwig; Garche, Juergen; Fabjan, Ch.; Tomazic G. (2004). "Possible use of vanadium redox-flow batteries for energy storage in small grids and stand-alone photovoltaic systems". Journal of Power Sources. 127 (1–2): 98–104. Bibcode:2004JPS...127...98J. doi:10.1016/j.jpowsour.2003.09.066.
  59. Rychcik, M.; Skyllas-Kazacos, M. (1988). "Characteristics of a new all-vanadium redox flow battery". Journal of Power Sources. 22 (1): 59–67. doi:10.1016/0378-7753(88)80005-3. ISSN 0378-7753.
  60. Guan, H.; Buchheit R. G. (2004). "Corrosion Protection of Aluminum Alloy 2024-T3 by Vanadate Conversion Coatings". Corrosion. 60 (3): 284–296. doi:10.5006/1.3287733.
  61. Kariatsumari, Koji (February 2008). "Li-Ion Rechargeable Batteries Made Safer". Nikkei Business Publications, Inc. Retrieved 10 December 2008.
  62. Rehder, Dieter (2013). "Chapter 5. Vanadium. Its Role for Humans". In Astrid Sigel; Helmut Sigel; Roland K. O. Sigel. Interrelations between Essential Metal Ions and Human Diseases. Metal Ions in Life Sciences. 13. Springer. pp. 139–169. doi:10.1007/978-94-007-7500-8_5.
  63. Sigel, Astrid; Sigel, Helmut, eds. (1995). Vanadium and Its Role in Life. Metal Ions in Biological Systems. 31. CRC. ISBN 0-8247-9383-8.
  64. Gribble, Gordon W. (1999). "The diversity of naturally occurring organobromine compounds". Chemical Society Reviews. 28: 335–346. doi:10.1039/a900201d.
  65. Butler, Alison; Carter-Franklin, Jayme N. (2004). "The role of vanadium bromoperoxidase in the biosynthesis of halogenated marine natural products". Natural Product Reports. 21 (1): 180–8. doi:10.1039/b302337k. PMID 15039842.
  66. Robson, R. L.; Eady, R. R.; Richardson, T. H.; Miller, R. W.; Hawkins, M.; Postgate, J. R. (1986). "The alternative nitrogenase of Azotobacter chroococcum is a vanadium enzyme". Nature. London. 322 (6077): 388–390. Bibcode:1986Natur.322..388R. doi:10.1038/322388a0.
  67. Smith, M. J. (1989). "Vanadium biochemistry: The unknown role of vanadium-containing cells in ascidians (sea squirts)". Experientia. 45 (5): 452–7. doi:10.1007/BF01952027. PMID 2656286.
  68. MacAra, Ian G.; McLeod, G.C.; Kustin, Kenneth (1979). "Tunichromes and metal ion accumulation in tunicate blood cells". Comparative Biochemistry and Physiology B. 63 (3): 299–302. doi:10.1016/0305-0491(79)90252-9.
  69. Trefry, John H.; Metz, Simone (1989). "Role of hydrothermal precipitates in the geochemical cycling of vanadium". Nature. 342 (6249): 531–533. Bibcode:1989Natur.342..531T. doi:10.1038/342531a0.
  70. Weiss, H; Guttman, MA; Korkisch, J; Steffan, I (1977). "Comparison of methods for the determination of vanadium in sea-water". Talanta. 24 (8): 509–11. doi:10.1016/0039-9140(77)80035-0. PMID 18962130.
  71. Ruppert, Edward E.; Fox, Richard, S.; Barnes, Robert D. (2004). Invertebrate Zoology (7th ed.). Cengage Learning. p. 947. ISBN 81-315-0104-3.
  72. Kneifel, Helmut; Bayer, Ernst (1997). "Determination of the Structure of the Vanadium Compound, Amavadine, from Fly Agaric". Angewandte Chemie International Edition in English. 12 (6): 508. doi:10.1002/anie.197305081. ISSN 0570-0833.
  73. Falandysz, J.; Kunito, T.; Kubota, R.; Lipka, K.; Mazur, A.; Falandysz, Justyna J.; Tanabe, S. (2007). "Selected elements in fly agaric Amanita muscaria". Journal of Environmental Science and Health, Part A. 42 (11): 1615–1623. doi:10.1080/10934520701517853. PMID 17849303.
  74. Berry, Robert E.; Armstrong, Elaine M.; Beddoes, Roy L.; Collison, David; Ertok, Nigar; Helliwell, Madeleine; Garner, David (1999). "The Structural Characterization of Amavadin". Angewandte Chemie International Edition. 38 (6): 795–797. doi:10.1002/(SICI)1521-3773(19990315)38:6<795::AID-ANIE795>3.0.CO;2-7.
  75. Schwarz, Klaus; Milne, David B. (1971). "Growth Effects of Vanadium in the Rat". Science. 174 (4007): 426–428. Bibcode:1971Sci...174..426S. doi:10.1126/science.174.4007.426. JSTOR 1731776. PMID 5112000.
  76. Yeh, Gloria Y.; Eisenberg, David M.; Kaptchuk, Ted J.; Phillips, Russell S. (2003). "Systematic Review of Herbs and Dietary Supplements for Glycemic Control in Diabetes". Diabetes Care. 26 (4): 1277–1294. doi:10.2337/diacare.26.4.1277. PMID 12663610.
  77. Talbott, Shawn M.; Hughes, Kerry (2007). "Vanadium". The Health Professional's Guide to Dietary Supplements. Lippincott Williams & Wilkins. pp. 419–422. ISBN 978-0-7817-4672-4.
  78. Halberstam, M; Cohen, N; Shlimovich, P; Rossetti, L; Shamoon, H (1996). "Oral vanadyl sulfate improves insulin sensitivity in NIDDM but not in obese nondiabetic subjects". Diabetes. 45 (5): 659–66. doi:10.2337/diabetes.45.5.659. PMID 8621019.
  79. Boden, G; Chen, X; Ruiz, J; Van Rossum, GD; Turco, S (1996). "Effects of vanadyl sulfate on carbohydrate and lipid metabolism in patients with non-insulin dependent diabetes mellitus". Metabolism. 45 (9): 1130–5. doi:10.1016/S0026-0495(96)90013-X. PMID 8781301.
  80. Goldfine, AB; Patti, ME; Zuberi, L; Goldstein, BJ; Leblanc, R; Landaker, EJ; Jiang, ZY; Willsky, GR; Kahn, CR (2000). "Metabolic effects of vanadyl sulfate in humans with non-insulin-dependent diabetes mellitus: in vivo and in vitro studies". Metabolism. 49 (3): 400–10. doi:10.1016/S0026-0495(00)90418-9. PMID 10726921.
  81. Badmaev, V; Prakash, Subbalakshmi; Majeed, Muhammed (1999). "Vanadium: a review of its potential role in the fight against diabetes". Altern Complement Med. 5 (3): 273–291. doi:10.1089/acm.1999.5.273. PMID 10381252.
  82. Goldwaser, I; Li, J; Gershonov, E; Armoni, M; Karnieli, E; Fridkin, M; Shechter, Y (1999). "L-Glutamic Acid gamma -Monohydroxamate. A Potentiator of Vanadium-Evoked Glucose Metabolism in vitro and in vivo". J Biol Chem. 274 (37): 26617–26624. doi:10.1074/jbc.274.37.26617. PMID 10473627.
  83. Aureliano, Manuel; Crans, Debbie C. (2009). "Decavanadate and oxovanadates: Oxometalates with many biological activities". Journal Inorganic Biochemistry. 103: 536–546. doi:10.1016/j.jinorgbio.2008.11010.
  84. Roschin, A. V. (1967). "Toxicology of vanadium compounds used in modern industry". Gig Sanit. (Water Res.). 32 (6): 26–32. PMID 5605589.
  85. 1 2 "Occupational Safety and Health Guidelines for Vanadium Pentoxide". Occupational Safety and Health Administration. Retrieved 29 January 2009.
  86. Sax, N. I. (1984). Dangerous Properties of Industrial Materials (6th ed.). Van Nostrand Reinhold Company. pp. 2717–2720.
  87. 1 2 Ress, N. B.; et al. (2003). "Carcinogenicity of inhaled vanadium pentoxide in F344/N rats and B6C3F1 mice". Toxicological Sciences. 74 (2): 287–296. doi:10.1093/toxsci/kfg136. PMID 12773761.
  88. Jörg M. Wörle-Knirsch; Katrin Kern; Carsten Schleh; Christel Adelhelm; Claus Feldmann & Harald F. Krug (2007). "Nanoparticulate Vanadium Oxide Potentiated Vanadium Toxicity in Human Lung Cells". Environ. Sci. Technol. 41 (1): 331–336. Bibcode:2007EnST...41..331W. doi:10.1021/es061140x. PMID 17265967.
  89. Ścibior, A.; Zaporowska, H.; Ostrowski, J. (2006). "Selected haematological and biochemical parameters of blood in rats after subchronic administration of vanadium and/or magnesium in drinking water". Archives of Environmental Contamination and Toxicology. 51 (2): 287–295. doi:10.1007/s00244-005-0126-4. PMID 16783625.
  90. Gonzalez-Villalva, A.; et al. (2006). "Thrombocytosis induced in mice after subacute and subchronic V2O5 inhalation". Toxicology and Industrial Health. 22 (3): 113–116. doi:10.1191/0748233706th250oa. PMID 16716040.
  91. Kobayashi, Kazuo; Himeno, Seiichiro; Satoh, Masahiko; Kuroda, Junji; Shibata, Nobuo; Seko, Yoshiyuki; Hasegawa, Tatsuya (2006). "Pentavalent vanadium induces hepatic metallothionein through interleukin-6-dependent and -independent mechanisms". Toxicology. 228 (2–3): 162–170. doi:10.1016/j.tox.2006.08.022. PMID 16987576.
  92. Soazo, Marina; Garcia, Graciela Beatriz (2007). "Vanadium exposure through lactation produces behavioral alterations and CNS myelin deficit in neonatal rats". Neurotoxicology and Teratology. 29 (4): 503–510. doi:10.1016/j.ntt.2007.03.001. PMID 17493788.
  93. Barceloux, Donald G.; Barceloux, Donald (1999). "Vanadium". Clinical Toxicology. 37 (2): 265–278. doi:10.1081/CLT-100102425. PMID 10382561.
  94. Duffus, J. H. (2007). "Carcinogenicity classification of vanadium pentoxide and inorganic vanadium compounds, the NTP study of carcinogenicity of inhaled vanadium pentoxide, and vanadium chemistry". Regulatory Toxicology and Pharmacology. 47 (1): 110–114. doi:10.1016/j.yrtph.2006.08.006. PMID 17030368.
  95. Opreskos, Dennis M. (1991). "Toxicity Summary for Vanadium". Oak Ridge National Laboratory. Retrieved 8 November 2008.
  96. Woodyard, Doug (2009-08-18). Pounder's Marine Diesel Engines and Gas Turbines. p. 92. ISBN 9780080943619.
  97. Totten, George E; Westbrook, Steven R; Shah, Rajesh J (2003-06-01). Fuels and Lubricants Handbook: Technology, Properties, Performance, and Testing. p. 152. ISBN 9780803120969.

Further reading

Wikimedia Commons has media related to Vanadium.
Look up vanadium in Wiktionary, the free dictionary.
Videos
Research papers

This article is issued from Wikipedia - version of the 12/3/2016. The text is available under the Creative Commons Attribution/Share Alike but additional terms may apply for the media files.