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| verifiedrevid = 409010929 |
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| Name = Uranium dioxide |
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| verifiedrevid = 446398737 |
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| ImageFile = UO2lattice.jpg |
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| IUPACName = Uranium dioxide<br/>Uranium(IV) oxide |
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| Name = Uranium dioxide |
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| ImageFile = UO2lattice.jpg |
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| OtherNames = Urania<br/>Uranous oxide |
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| IUPACName = Uranium dioxide<br/>Uranium(IV) oxide |
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| Section1 = {{Chembox Identifiers |
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| OtherNames = Urania<br/>Uranous oxide |
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| SystematicName = |
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| Section1 = {{Chembox Identifiers |
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| CASNo = 1344-57-6 |
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| CASNo = 1344-57-6 |
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| CASNo_Ref = {{cascite|correct|CAS}} |
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| CASNo_Ref = {{cascite|correct|CAS}} |
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| UNII_Ref = {{fdacite|correct|FDA}} |
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| UNII = L70487KUZO |
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| RTECS = YR4705000 |
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| RTECS = YR4705000 |
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| PubChem = 10916 |
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| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}} |
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| ChemSpiderID = 10454 |
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| EC_number = 215-700-3 |
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| StdInChI=1S/2O.U |
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| StdInChIKey = FCTBKIHDJGHPPO-UHFFFAOYSA-N |
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| SMILES = O==O |
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| Section2 = {{Chembox Properties |
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| Section2 = {{Chembox Properties |
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| Formula = UO<sub>2</sub> |
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| Formula = UO<sub>2</sub> |
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| MolarMass = 270.03 g/mol |
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| MolarMass = 270.03 g/mol |
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| Appearance = black powder |
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| Appearance = black powder |
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| Solubility = insoluble |
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| Solubility = insoluble |
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| MeltingPt = 2865 °C (3140 K) |
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| MeltingPtC = 2865 |
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| Section3 = {{Chembox Structure |
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| Section3 = {{Chembox Structure |
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| CrystalStruct = ] (cubic), ] |
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| CrystalStruct = ] (cubic), ] |
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| SpaceGroup = Fm{{overline|3}}m, No. 225 |
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| SpaceGroup = Fm{{overline|3}}m, No. 225 |
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| Coordination = Tetrahedral (O<sup>2–</sup>); cubic (U<sup>IV</sup>) |
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| Coordination = Tetrahedral (O<sup>2−</sup>); cubic (U<sup>IV</sup>) |
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| LattConst_a = 547.1 pm <ref name=lp>{{cite journal |doi=10.1016/j.jnucmat.2015.01.029 |title=Accurate lattice parameter measurements of stoichiometric uranium dioxide |journal=Journal of Nuclear Materials |volume=459 |pages=135–42 |year=2015 |last1=Leinders |first1=Gregory |last2=Cardinaels |first2=Thomas |last3=Binnemans |first3=Koen |last4=Verwerft |first4=Marc |bibcode=2015JNuM..459..135L |s2cid=97183844 | url=https://zenodo.org/record/884499}}</ref> |
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| Section7 = {{Chembox Hazards |
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| Section4 = {{Chembox Thermochemistry |
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| DeltaHf = −1084 kJ·mol<sup>−1</sup><ref name=b1>{{cite book| author = Zumdahl, Steven S.|title =Chemical Principles 6th Ed| publisher = Houghton Mifflin Company| year = 2009| isbn = 978-0-618-94690-7|page=A23}}</ref> |
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| ExternalMSDS = |
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| Entropy = 78 J·mol<sup>−1</sup>·K<sup>−1</sup><ref name=b1/> |
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| EUIndex = 092-002-00-3 |
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| EUClass = Very toxic ('''T+''')<br/>Dangerous for the environment ('''N''') |
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| RPhrases = {{R26/28}}, {{R33}}, {{R51/53}} |
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| SPhrases = {{S1/2}}, {{S20/21}}, {{S45}}, {{S61}} |
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| Section7 = {{Chembox Hazards |
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| GHSPictograms = {{GHS06}}{{GHS08}}{{GHS09}} |
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| GHSSignalWord = Danger |
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| NFPA-O = |
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| HPhrases = {{H-phrases|300|330|373|410}} |
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| FlashPt = Non-flammable |
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| PPhrases = {{P-phrases|260|264|270|271|273|284|301+310|304+340|310|314|320|321|330|391|403+233|405|501}} |
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| NFPA-H = 4 |
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| NFPA-F = 0 |
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| NFPA-R = 0 |
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| NFPA-S =RA |
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| FlashPt = N/A |
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| Section8 = {{Chembox Related |
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| OtherAnions = ] <br> ] |
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| OtherCations = ] <br> ] |
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'''Uranium dioxide''' or '''uranium(IV) oxide ({{Uranium}}{{Oxygen}}<sub>2</sub>)''', also known as '''urania''' or '''uranous oxide''', is an ] of ], and is a black, radioactive, crystalline powder that naturally occurs in the mineral ]. It is used in ] rods in ]. A mixture of uranium and ] dioxides is used as ]. Prior to 1960 it was used as yellow and black color in ] ]s and ]. |
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'''Uranium dioxide''' or '''uranium(IV) oxide ({{chem2|UO2}})''', also known as '''urania''' or '''uranous oxide''', is an ] of ], and is a black, ], ]line powder that naturally occurs in the mineral ]. It is used in ] rods in ]. A mixture of uranium and ] dioxides is used as ]. Prior to 1960, it was used as yellow and black color in ] and glass. |
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==Production== |
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==Production== |
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Uranium dioxide is produced by ] ] with ]. |
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Uranium dioxide is produced by ] ] with ]. |
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:UO<sub>3</sub> + H<sub>2</sub> → UO<sub>2</sub> + H<sub>2</sub>O at 700 °C (970 K) |
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:UO<sub>3</sub> + H<sub>2</sub> → UO<sub>2</sub> + H<sub>2</sub>O at 700 °C (973 K) |
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This reaction takes part in the ] and ] for nuclear fuel. |
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This reaction plays an important part in the creation of ] through ] and ]. |
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==Chemistry== |
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==Chemistry== |
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===Structure=== |
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===Structure=== |
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The solid is ] with (has the same structure as) ] (]), where each U is surrounded by eight O nearest neighbors in a cubic arrangement. In addition, the dioxides of ], ], and the ] elements from ] through ] have the same structures.<ref>{{Cite journal |last1=Petit |first1=L. |last2=Svane |first2=A. |last3=Szotek |first3=Z. |last4=Temmerman |first4=W. M. |last5=Stocks |first5=G. M. |date=2010-01-07 |title=Electronic structure and ionicity of actinide oxides from first principles |url=https://link.aps.org/doi/10.1103/PhysRevB.81.045108 |journal=Physical Review B |volume=81 |issue=4 |pages=045108 |doi=10.1103/PhysRevB.81.045108|arxiv=0908.1806 |bibcode=2010PhRvB..81d5108P |s2cid=118365366 }}</ref> No other elemental dioxides have the fluorite structure. Upon melting, the measured average U-O coordination reduces from 8 in the crystalline solid (UO<sub>8</sub> cubes), down to 6.7±0.5 (at 3270 K) in the melt.<ref name = "Skinner2014">{{cite journal |doi=10.1126/science.1259709 |pmid=25414311 |title=Molten uranium dioxide structure and dynamics |journal=Science |volume=346 |issue=6212 |pages=984–7 |year=2014 |last1=Skinner |first1=L. B. |last2=Benmore |first2=C. J. |last3=Weber |first3=J. K. R. |last4=Williamson |first4=M. A. |last5=Tamalonis |first5=A. |last6=Hebden |first6=A. |last7=Wiencek |first7=T. |last8=Alderman |first8=O. L. G. |last9=Guthrie |first9=M. |last10=Leibowitz |first10=L. |last11=Parise |first11=J. B. |bibcode=2014Sci...346..984S |osti=1174101 |s2cid=206561628 |url=https://www.osti.gov/biblio/1174101 }}</ref> Models consistent with these measurements show the melt to consist mainly of UO<sub>6</sub> and UO<sub>7</sub> polyhedral units, where roughly {{frac|2|3}} of the connections between polyhedra are corner sharing and {{frac|1|3}} are edge sharing.<ref name = "Skinner2014"/> |
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The solid is ] with (has the same structure as) ] (]). In addition, the dioxides of ] and ] have the same structures. |
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<gallery> |
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UO2 Powder.jpg|Uranium dioxide |
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UO2 Pellet.jpg|Sintered uranium dioxide pellet |
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</gallery> |
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===Oxidation=== |
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===Oxidation=== |
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Uranium dioxide is ] in contact with ] to the ]. |
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Uranium dioxide is ] in contact with ] to the ]. |
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:3 UO<sub>2</sub> + O<sub>2</sub> → U<sub>3</sub>O<sub>8</sub> at 700 °C (970 K) |
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:3 UO<sub>2</sub> + O<sub>2</sub> → U<sub>3</sub>O<sub>8</sub> at 700 °C (973 K) |
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The ] of uranium dioxide has been investigated in detail as the ] of uranium dioxide controls the rate at which used ] dissolves. See the ] page for further details. ] increases the oxidation rate of ] and ] metals.<ref>{{cite web|url=http://www.osti.gov/bridge/servlets/purl/756904-DrPADO/webviewable/756904.pdf| title =Reactions of Plutonium Dioxide with Water and Oxygen-Hydrogen Mixtures: Mechanisms for Corrosion of Uranium and Plutonium| accessdate=2009-06-06}}</ref> |
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The ] of uranium dioxide has been investigated in detail as the ] of uranium dioxide controls the rate at which used ] dissolves. See ] for further details. ] increases the oxidation rate of ] and uranium metals.<ref>{{cite journal|url=http://www.osti.gov/bridge/servlets/purl/756904-DrPADO/webviewable/756904.pdf| title =Reactions of Plutonium Dioxide with Water and Oxygen-Hydrogen Mixtures: Mechanisms for Corrosion of Uranium and Plutonium| access-date=2009-06-06|year=1999|last1=Haschke|first1=John M|last2=Allen|first2=Thomas H|last3=Morales|first3=Luis A| doi =10.2172/756904}}</ref><ref>{{Cite journal |doi=10.1016/S0925-8388(00)01222-6 |title=Reactions of plutonium dioxide with water and hydrogen–oxygen mixtures: Mechanisms for corrosion of uranium and plutonium |journal=Journal of Alloys and Compounds |volume=314 |issue=1–2 |pages=78–91 |year=2001 |last1=Haschke |first1=John M |last2=Allen |first2=Thomas H |last3=Morales |first3=Luis A }}</ref> |
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===Carbonization=== |
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Uranium dioxide is ] in contact with ], forming ] and ]. |
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:<chem>UO2 \ + \ 4C -> UC2 \ + \ 2CO</chem>. |
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This process must be done under an ] as uranium carbide is easily oxidized back into ]. |
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==Uses== |
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==Uses== |
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] |
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===Nuclear fuel=== |
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===Nuclear fuel=== |
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UO<sub>2</sub> is used mainly as ], specifically as UO<sub>2</sub> or as a mixture of UO<sub>2</sub> and PuO<sub>2</sub> (]) called a mixed oxide (]) for ]s in ]s. |
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UO<sub>2</sub> is used mainly as ], specifically as UO<sub>2</sub> or as a mixture of UO<sub>2</sub> and PuO<sub>2</sub> (]) called a mixed oxide (]), in the form of ]s in ]s. |
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Note that the ] of uranium dioxide is very low when compared with ], ], ] and ] cladding material. This low thermal conductivity can result in localised overheating in the centres of fuel pellets. The graph below shows the different temperature gradients in different fuel compounds. For these fuels the thermal power density is the same and the diameter of all the pellets are the same. |
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{{clear}} |
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The ] of uranium dioxide is very low when compared with ], ], ] and ] cladding material. This low thermal conductivity can result in localised overheating in the centres of fuel pellets. The graph below shows the different temperature gradients in different fuel compounds. For these fuels, the thermal power density is the same and the diameter of all the pellets are the same.{{citation needed|date=January 2017}} |
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<Gallery widths="360px" heights="300px" perrow="2"> |
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Image:ZrUthermalcond.png|The thermal conductivity of zirconium metal and uranium dioxide as a function of temperature |
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<gallery class="center"> |
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Image:rim200pd250rad1000fueltemp.jpg|This is a 20 mm diameter fuel pellet, note that the central temperature is very different for the different fuel solids, also for the different pellets it has the lowest centre line temperature. |
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FuelPellet1.jpg|Uranium oxide fuel pellet |
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RIAN archive 132609 Uranium dioxide fuel pellet starting material.jpg|Starting material containers for uranium dioxide fuel pellet production at a plant in Russia |
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</gallery> |
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</gallery> |
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===Color for ceramics glaze=== |
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===Color for glass ceramic glaze=== |
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] |
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All uranium oxides were used to color glass and ceramics. Uranium oxide-based ceramics become green or black when fired in a reducing atmosphere and yellow to orange when fired with oxygen. Orange-colored ] is a well-known example of a product with a uranium-based glaze. Uranium oxide has also been used in formulations of ], ], and ]. |
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Uranium oxide (urania) was used to color glass and ceramics prior to World War II, and until the applications of radioactivity were discovered this was its main use. In 1958 the military in both the US and Europe allowed its commercial use again as depleted uranium, and its use began again on a more limited scale. Urania-based ceramic glazes are dark green or black when fired in a reduction or when UO<sub>2</sub> is used; more commonly it is used in oxidation to produce bright yellow, orange and red glazes.<ref>{{Cite book|url=http://www.uranglasuren.com/|title=Uran in der Keramik. Geschichte - Technik - Hersteller|last=Örtel|first=Stefan}}</ref> Orange-colored ] is a well-known example of a product with a urania-colored glaze. ] is pale green to yellow and often has strong fluorescent properties. Urania has also been used in formulations of ] and ]. It is possible to determine with a ] if a glaze or glass produced before 1958 contains urania. |
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===Other uses=== |
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Prior to 1960, uranium oxides were used as colored glazes. It is possible to determine with a ] if a glaze or glass contains uranium oxides. |
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Prior to the realisation of the harmfulness of radiation, uranium was included in false teeth and dentures, as its slight fluorescence made the dentures appear more like real teeth in a variety of lighting conditions.{{fact|date= November 2023}} |
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] UO<sub>2</sub> (DUO<sub>2</sub>) can be used as a material for ]. For example, ] is a "heavy ]" material where ] is replaced with uranium dioxide aggregate; this material is investigated for use for ]s for ]. Casks can be also made of DUO<sub>2</sub>-] ], a ] made of an ] of uranium dioxide serving as radiation shielding, ] and/or ] serving as ] absorber and moderator, and steel as the matrix, whose high thermal conductivity allows easy removal of decay heat.{{citation needed|date=January 2017}} |
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===Other use=== |
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] UO<sub>2</sub> (DUO<sub>2</sub>) can be used as a material for ]. For example, ] is a "heavy ]" material where ] is replaced with uranium dioxide aggregate; this material is investigated for use for ]s for ]. Casks can be also made of DUO<sub>2</sub>-] ], a ] made of an ] of uranium dioxide serving as radiation shielding, ] and/or ] serving as ] absorber and moderator, and steel as the matrix, whose high thermal conductivity allows easy removal of decay heat. |
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Depleted uranium dioxide can be also used as a ], e.g. for degradation of ]s in gaseous phase, ] of ] to ], and removal of ] from ]. It has high efficiency and long-term stability when used to destroy VOCs when compared with some of the commercial ]s, such as ]s, ], and ] catalysts. Much research is being done in this area, DU being favoured for the uranium component due to its low radioactivity.<ref>{{cite journal|author= Hutchings GJ|title= A Uranium-Oxide-Based Catalysts for the Destruction of Volatile Chloro-Organic compounds| journal= Nature|year= 1996|volume= 384|issue= 6607| pages= 341–343|doi= 10.1038/384341a0|last2= Heneghan|first2= Catherine S.|last3= Hudson|first3= Ian D.|last4= Taylor|first4= Stuart H. |bibcode = 1996Natur.384..341H }}</ref> |
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Depleted uranium dioxide can be also used as a ], e.g. for degradation of ]s in gaseous phase, ] of ] to ], and removal of ] from ]. It has high efficiency and long-term stability when used to destroy VOCs when compared with some of the commercial ]s, such as ]s, ], and ] catalysts. Much research is being done in this area, DU being favoured for the uranium component due to its low radioactivity.<ref>{{cite journal |doi=10.1038/384341a0 |title=Uranium-oxide-based catalysts for the destruction of volatile chloro-organic compounds |journal=Nature |volume=384 |issue=6607 |pages=341–3 |year=1996 |last1=Hutchings |first1=Graham J. |last2=Heneghan |first2=Catherine S. |last3=Hudson |first3=Ian D. |last4=Taylor |first4=Stuart H. |bibcode=1996Natur.384..341H |s2cid=4299921 }}</ref> |
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The use of uranium dioxide as a material for ] is being investigated. The batteries could have high ] and potential of 4.7 V per cell. Another investigated application is in ]s for solar-assisted hydrogen production where UO<sub>2</sub> is used as a ]. In earlier times, uranium dioxide was also used as heat conductor for current limitation (URDOX-resistor), which was the first use of its semiconductor properties. |
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The use of uranium dioxide as a material for ] is being investigated. The batteries could have high ] and potential of 4.7 V per cell. Another investigated application is in ]s for solar-assisted hydrogen production where UO<sub>2</sub> is used as a ]. In earlier times, uranium dioxide was also used as heat conductor for current limitation (URDOX-resistor), which was the first use of its semiconductor properties.{{citation needed|date=January 2017}} |
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Uranium dioxide displays strong ] in the ] state, observed at cryogenic temperatures below 30 ]s. Accordingly, the linear ] found in UO<sub>2</sub> changes sign with the applied magnetic field and exhibits magnetoelastic memory switching phenomena at record high switch-fields of 180,000 Oe.<ref>{{cite journal |doi=10.1038/s41467-017-00096-4 |title=Piezomagnetism and magnetoelastic memory in uranium dioxide. |journal=Nature Communications |volume=8 |pages=99 |year=2017 |last1=Jaime |first1=Marcelo |last2=Saul |first2=Andres |last3=Salamon |first3=Myron B. |last4=Zapf |first4=Vivien |last5=Harrison |first5=Neil |last6=Durakiewicz |first6=Tomasz |last7=Lashley |first7=Jason C. |last8=Andersson |first8=David A. |last9=Stanek |first9=Christopher R. |last10=Smith |first10=James L. |last11=Gofryk |first11=Krysztof|issue=1 |pmid=28740123 |pmc=5524652 |bibcode=2017NatCo...8...99J }}</ref> The microscopic origin of the material magnetic properties lays in the face-centered-cubic crystal lattice symmetry of uranium atoms, and its response to applied magnetic fields.<ref>{{cite journal |doi=10.1038/s43246-021-00121-6 |bibcode=2021CoMat...2...17A |title=Piezomagnetic switching and complex phase equilibria in uranium dioxide. |journal=Communications Materials |volume=2 |issue=1 |pages=17 |year=2021 |last1=Antonio |first1=Daniel J. |last2=Weiss |first2=Joel T. |last3=Shanks |first3=Katherine S. |last4=Ruff |first4=Jacob P.C. |last5=Jaime |first5=Marcelo |last6=Saul |first6=Andres |last7=Swinburne |first7=Thomas |last8=Salamon |first8=Myron B. |last9=Lavina |first9=Barbara |last10=Koury |first10=Daniel |last11=Gruner |first11=Sol M. |last12=Andersson |first12=David A. |last13=Stanek |first13=Christopher R. |last14=Durakiewicz |first14=Tomasz |last15=Smith |first15=James L. |last16=Islam |first16=Zahir |last17=Gofryk |first17=Krysztof|arxiv=2104.06340 |s2cid=231812027 }}</ref> |
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===Semiconductor properties=== |
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===Semiconductor properties=== |
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The ] of uranium dioxide is comparable to these of ] and ], near the optimum for efficiency vs band gap curve for absorption of solar radiation, suggesting its possible use for very efficient ]s based on ] structure; it also absorbs at five different wavelengths, including infrared, further enhancing its efficiency. Its intrinsic conductivity at room temperature is about the same as of ] silicon.<ref>{{cite journal|author=An, Y.Q. ''et al.''|title=Ultrafast Hopping Dynamics of 5f Electrons in the Mott Insulator UO(2) Studied by Femtosecond Pump-Probe Spectroscopy|journal=Phys. Rev. Lett.|year=2011|volume=107|issue=20|pages=207402|doi=10.1103/PhysRevLett.106.207402|bibcode = 2011PhRvL.106t7402A }}</ref> |
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The ] of uranium dioxide is comparable to those of ] and ], near the optimum for efficiency vs band gap curve for absorption of solar radiation, suggesting its possible use for very efficient ]s based on ] structure; it also absorbs at five different wavelengths, including infrared, further enhancing its efficiency. Its intrinsic conductivity at room temperature is about the same as of ] silicon.<ref>{{cite journal |doi=10.1103/PhysRevLett.106.207402 |pmid=21668262 |title=Ultrafast Hopping Dynamics of 5''f'' Electrons in the Mott Insulator UO<sub>2</sub> Studied by Femtosecond Pump-Probe Spectroscopy |journal=Physical Review Letters |volume=106 |issue=20 |pages=207402 |year=2011 |last1=An |first1=Yong Q. |last2=Taylor |first2=Antoinette J.|author2-link=Antoinette Taylor |last3=Conradson |first3=Steven D. |last4=Trugman |first4=Stuart A. |last5=Durakiewicz |first5=Tomasz |last6=Rodriguez |first6=George |bibcode=2011PhRvL.106t7402A }}</ref> |
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The ] of uranium dioxide is about 22, which is almost twice as high as of silicon (11.2) and GaAs (14.1). This is an advantage over Si and GaAs in construction of ]s, as it may allow higher density integration with higher ]s and with lower susceptibility to the ] ] breakdown. |
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The ] of uranium dioxide is about 22, which is almost twice as high as of silicon (11.2) and GaAs (14.1). This is an advantage over Si and GaAs in the construction of ]s, as it may allow higher density integration with higher ]s and with lower susceptibility to the ] ] breakdown. |
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The ] of uranium dioxide at room temperature is about 750 µV/K, a value significantly higher than the 270 µV/K of ] (Tl<sub>2</sub>SnTe<sub>5</sub>) and ] (Tl<sub>2</sub>GeTe<sub>5</sub>) and of ]-] alloys, other materials promising for ] applications and ]s. |
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The ] of uranium dioxide at room temperature is about 750 μV/K, a value significantly higher than the 270 μV/K of ] (Tl<sub>2</sub>SnTe<sub>5</sub>) and ] (Tl<sub>2</sub>GeTe<sub>5</sub>) and of ]-] alloys, other materials promising for ] applications and ]s. |
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The ] impact of the<sup>235</sup>U and<sup>238</sup>U on its semiconducting properties was not measured {{as of|2005|lc=on}}. Due to the slow decay rate of these isotopes, it should not meaningfully influence the properties of uranium dioxide solar cells and thermoelectric devices, but it may become an important factor for ] chips. Use of ] oxide is necessary for this reason. The capture of alpha particles emitted during radioactive decay as helium atoms in the crystal lattice may also cause gradual long-term changes in its properties. |
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The ] impact of the <sup>235</sup>U and <sup>238</sup>U on its semiconducting properties was not measured {{as of|2005|lc=on}}. Due to the slow decay rate of these isotopes, it should not meaningfully influence the properties of uranium dioxide solar cells and thermoelectric devices, but it may become an important factor for ] chips. Use of ] oxide is necessary for this reason. The capture of alpha particles emitted during radioactive decay as helium atoms in the crystal lattice may also cause gradual long-term changes in its properties.{{citation needed|date=January 2017}} |
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The ] of the material dramatically influences its electrical properties. For example, the electrical conductivity of UO<sub>1.994</sub> is orders of magnitude lower at higher temperatures than the conductivity of UO<sub>2.001</sub>. |
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The ] of the material dramatically influences its electrical properties. For example, the electrical conductivity of UO<sub>1.994</sub> is orders of magnitude lower at higher temperatures than the conductivity of UO<sub>2.001</sub>{{citation needed|date=August 2021}}. |
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Uranium dioxide, like U<sub>3</sub>O<sub>8</sub>, is a ] material capable of withstanding high temperatures (about 2300 °C, in comparison with at most 200 °C for silicon or GaAs), making it suitable for high-temperature applications like thermophotovoltaic devices. |
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Uranium dioxide, like U<sub>3</sub>O<sub>8</sub>, is a ] material capable of withstanding high temperatures (about 2300 °C, in comparison with at most 200 °C for silicon or GaAs), making it suitable for high-temperature applications like thermophotovoltaic devices. |
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Uranium dioxide is also resistant to ] damage, making it useful for ] devices for special military and ] applications. |
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Uranium dioxide is also resistant to ] damage, making it useful for ] devices for special military and ] applications. |
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A ] of ] and a ] of UO<sub>2</sub> were successfully manufactured in a laboratory. |
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A ] of ] and a ] of UO<sub>2</sub> were successfully manufactured in a laboratory.<ref>{{cite journal |doi=10.1016/j.vacuum.2008.04.005 |title=Semiconductor devices fabricated from actinide oxides |journal=Vacuum |volume=83 |issue=1 |pages=226–8 |year=2008 |last1=Meek |first1=Thomas T. |last2=von Roedern |first2=B. |bibcode=2008Vacuu..83..226M }}</ref> |
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==Toxicity== |
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==Toxicity== |
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Uranium dioxide is known to be absorbed by ] in the lungs.<ref>Principles of Biochemical Toxicology. Timbrell, John. PA 2008 ISBN 0849373026</ref> |
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Uranium dioxide is known to be absorbed by ] in the lungs.<ref>Principles of Biochemical Toxicology. Timbrell, John. PA 2008 {{ISBN|0-8493-7302-6}}{{page needed|date=January 2017}}</ref> |
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==See also== |
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==See also== |
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==References== |
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==References== |
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==Further reading== |
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==Further reading== |
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*{{cite journal|author= Barrett SA, Jacobson AJ, Tofield BC, Fender BEF|title= The preparation and structure of barium uranium oxide BaUO<sub>3+x</sub>| journal= Acta Crystallographica B|year= 1982|volume= 38|issue= 11| pages= 2775–2781|doi= 10.1107/S0567740882009935 }} |
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*{{cite journal |doi=10.1107/S0567740882009935 |title=The preparation and structure of barium uranium oxide BaUO3+x |journal=Acta Crystallographica Section B |volume=38 |issue=11 |pages=2775 |year=1982 |last1=Barrett |first1=S. A. |last2=Jacobson |first2=A. J. |last3=Tofield |first3=B. C. |last4=Fender |first4=B. E. F. |bibcode=1982AcCrB..38.2775B }} |
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==External links== |
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==External links== |
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* {{Webarchive|url=https://web.archive.org/web/20120901192557/http://web.ead.anl.gov/uranium/pdf/WM01Semicond.pdf |date=2012-09-01 }} |
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* The <span class="plainlinks"> {{Webarchive|url=https://web.archive.org/web/20130916230607/http://ibilabs.com/Uranium%20Oxide,%20di.htm |date=2013-09-16 }}</span> International Bio-Analytical Industries, Inc. |
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{{Uranium compounds}} |
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{{Oxides}} |
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{{DEFAULTSORT:Uranium Dioxide}} |
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{{DEFAULTSORT:Uranium Dioxide}} |
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