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| {{Infobox unbinilium}}
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| '''Unbinilium''' {{IPAc-en|uː|n|b|aɪ|ˈ|n|ɪ|l|i|ə|m}}, also called '''[[Mendeleev's predicted elements|eka]]'''-'''[[radium]]''' or element 120, is the temporary, [[systematic element name]] of a hypothetical [[chemical element]] in the [[periodic table]] that has the temporary symbol '''Ubn''' and has the [[atomic number]] 120.
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| Since unbinilium should be placed below the [[alkaline earth metals]] it possibly has properties similar to those of [[radium]] or [[barium]].
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| Attempts to date to synthesize the element using fusion reactions at low excitation energy have met with failure, although there are reports that the fission of nuclei of unbinilium at very high excitation has been successfully measured, indicating a strong shell effect at Z=120.
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| ==Attempts at synthesis==
| | The better companies will even send down trained staff for the full [http://Kplusd.udp.cl/index.php/Six_Signs_You_Made_A_Great_Impact_On_Best_Security_Dvr inspection] of the premises and find the best spots to set up the CCTV cameras cctv dvr system in in your case. The CCTV cameras help a fantastic deal in deterring crime in places [http://www.infoforthai.com/forum/go.php?http://cctvdvrreviews.com cctv camera and dvr system] like cctv dvr review railway stations, banks, hospitals [http://www.caramelmature.com/cms2/out.php?id=1593018&gid=237&c=1&s=85&url=http%3A//cctvdvrreviews.com wireless cctv camera Dvr System] as well as other crowded areas where the eye from the police may not reach. Cctv dvr viewer linux In theory DVR is nothing but a recording device with a [http://moto-slownik.pl/Ideas_Formulas_And_Shortcuts_For_Samsung_Svr_1640a hard disk] inside to hold each of the [http://www.lookjtb.com/common/look/othersite/index.asp?target=http://cctvdvrreviews.com mac dvr viewer software for cctv security cameras download] programs that you receive cctv [http://www.marketingclinicpartners.com/blog-entry/-/blogs/digital-shift-news-april-26-2013?p_p_auth=Bch0qBMi&_33_redirect=http%3A//cctvdvrreviews.com cctv dvr case] camera plugin from satellite or cable TV providers.<br><br>The ultimate aspect in a DVR safety structure is perhaps the security camera. Though marriage counseling professionals might frown since they begin to lose business, Direc - TV DVR by Tivo could prove to be the most effective thing marriage has ever seen.<br><br>If your profile is much like every other profile on Linked - In, you may not stand out, and you will 16 channel security dvr recorders not be found as easily. " Instead, write, "Connect SPX109 unit with SPX13 HDMI cable. [http://freeonlinetypinggames.com/typing-arcade/profile/736468/MeVangelde.html 16 camera dvr security system] cctv [http://wikivapia.com/How_To_Rent_A_Samsung_Cctv_Recorder_Without_Spending_An_Arm_And_A_Leg dvr ddns] If security camera systems you might be unemployed, you may state the key reason why your newest [http://Moto-Slownik.pl/Ideas_Formulas_And_Shortcuts_For_Samsung_Svr_1640a position] ended (in the event the company closed, by way of example) or which you are available immediately. Past scripts on this list have included Academy Awards Winners and Nominees. |
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| ===Neutron evaporation===
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| Following the success in obtaining [[ununoctium]] by the reaction between [[californium-249|<sup>249</sup>Cf]] and [[calcium-48|<sup>48</sup>Ca]], the discoverers started similar experiments in the hope of creating unbinilium (element 120) from [[iron-58|<sup>58</sup>Fe]] and [[plutonium-244|<sup>244</sup>Pu]].<ref>{{cite news|url=https://www.llnl.gov/str/April07/pdfs/04_07.4.pdf|title=A New Block on the Periodic Table|date=April 2007|publisher=Lawrence Livermore National Laboratory|accessdate=2008-01-18|format=PDF}}</ref> Isotopes of unbinilium are predicted to have alpha decay half-lives of the order of [[microsecond]]s.<ref name=prc08ADNDT08>{{cite journal|journal=Physical Reviews C|volume=77|page=044603|year=2008|title=Search for long lived heaviest nuclei beyond the valley of stability|first1=P. Roy |last1=Chowdhury |first2=C. |last2=Samanta |first3= D. N. |last3=Basu|doi=10.1103/PhysRevC.77.044603|bibcode = 2008PhRvC..77d4603C|issue=4|arxiv = 0802.3837 }}</ref><ref name="sciencedirect1">{{cite journal|journal=At. Data & Nucl. Data Tables |volume=94|pages=781–806|year=2008|title=Nuclear half-lives for α -radioactivity of elements with 100 ≤ Z ≤ 130|author=Chowdhury, R. P.; Samanta, C.; Basu, D.N.|doi=10.1016/j.adt.2008.01.003|bibcode = 2008ADNDT..94..781C|issue=6|arxiv = 0802.4161 }}</ref> In March–April 2007, the synthesis of unbinilium was attempted at the [[Joint Institute for Nuclear Research|Flerov Laboratory of Nuclear Reactions]] in [[Dubna]] by bombarding a [[plutonium]]-244 target with [[iron]]-58 [[ion]]s.<ref>[http://wwwinfo.jinr.ru/plan/ptp-2007/e751004.htm Synthesis of New Nuclei and Study of Nuclear Properties and Heavy-Ion Reaction Mechanisms]. jinr.ru</ref> Initial analysis revealed that no atoms of element 120 were produced providing a limit of 400 [[barn (unit)|fb]] for the cross section at the energy studied.<ref>{{cite journal|journal=Phys. Rev. C|volume=79|page=024603|year=2009|title=Attempt to produce element 120 in the <sup>244</sup>Pu+<sup>58</sup>Fe reaction|doi=10.1103/PhysRevC.79.024603|last1=Oganessian|first1=Yu.Ts.|last2=Utyonkov|first2=V.|last3=Lobanov|first3=Yu.|last4=Abdullin|first4=F.|last5=Polyakov|first5=A.|last6=Sagaidak|first6=R.|last7=Shirokovsky|first7=I.|last8=Tsyganov|first8=Yu.|last9=Voinov|first9=A.|issue=2 |bibcode = 2009PhRvC..79b4603O|display-authors=8 }}</ref>
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| :<math>\,^{244}_{94}\mathrm{Pu} + \,^{58}_{26}\mathrm{Fe} \to \,^{302}_{120}\mathrm{Ubn} ^{*} \to \ \mathit{fission\ only}</math>
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| The Russian team are planning to upgrade their facilities before attempting the reaction again.<ref name=Duellmann/>
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| In April 2007, the team at [[Gesellschaft für Schwerionenforschung|GSI]] attempted to create unbinilium using [[uranium]]-238 and [[nickel]]-64:<ref name=Duellmann/>
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| :<math>\,^{238}_{92}\mathrm{U} + \,^{64}_{28}\mathrm{Ni} \to \,^{302}_{120}\mathrm{Ubn} ^{*} \to \ \mathit{fission\ only}</math>
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| No atoms were detected providing a limit of 1.6 pb on the cross section at the energy provided. The GSI repeated the experiment with higher sensitivity in three separate runs from April–May 2007, Jan–March 2008, and Sept–Oct 2008, all with negative results and providing a cross section limit of 90 fb.<ref name=Duellmann/>
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| In June–July 2010, scientists at the GSI attempted the fusion reaction:<ref name=Duellmann/>
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| :<math>\,^{248}_{96}\mathrm{Cm} + \,^{54}_{24}\mathrm{Cr} \to \,^{302}_{120}\mathrm{Ubn} ^{*} </math>
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| They were unable to detect any atoms but exact details are not currently available.<ref name=Duellmann/>
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| In August–October 2011, a different team at the GSI using the TASCA facility tried the new reaction:<ref name=Duellmann/> | |
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| :<math>\,^{249}_{98}\mathrm{Cf} + \,^{50}_{22}\mathrm{Ti} \to \,^{299}_{120}\mathrm{Ubn} ^{*} </math>
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| Results from this experiment are not yet available.<ref name=Duellmann/>
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| ===Compound nucleus fission===
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| Unbinilium is of interest because it is part of the hypothesized [[island of stability]], with the [[Nuclear reaction#compound nucleus|compound nucleus]] <sup>302</sup>Ubn being the most stable of those that can be created directly by current methods. It has been calculated that Z=120 may in fact be the next proton magic number, rather than at Z=114 or 126.
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| Several experiments have been performed between 2000–2008 at the Flerov laboratory of Nuclear Reactions in Dubna studying the fission characteristics of the compound nucleus <sup>302</sup>Ubn. Two nuclear reactions have been used, namely <sup>244</sup>Pu+<sup>58</sup>Fe and <sup>238</sup>U+<sup>64</sup>Ni. The results have revealed how nuclei such as this fission predominantly by expelling closed shell nuclei such as <sup>132</sup>Sn (Z=50, N=82). It was also found that the yield for the fusion-fission pathway was similar between <sup>48</sup>Ca and <sup>58</sup>Fe projectiles, indicating a possible future use of <sup>58</sup>Fe projectiles in superheavy element formation.<ref>see [http://www1.jinr.ru/Reports/Reports_eng_arh.html Flerov lab annual reports 2000–2004]</ref>
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| In 2008, the team at GANIL, France, described the results from a new technique which attempts to measure the fission [[half-life]] of a compound nucleus at high excitation energy, since the yields are significantly higher than from neutron evaporation channels. It is also a useful method for probing the effects of shell closures on the survivability of compound nuclei in the super-heavy region, which can indicate the exact position of the next proton shell (Z=114, 120, 124, or 126).
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| The team studied the nuclear fusion reaction between uranium ions and a target of natural nickel:
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| ::::<math>\,^{238}_{92}\mathrm{U} + \,^{nat}_{28}\mathrm{Ni} \to \,^{296,298,299,300,302}\mathrm{Ubn} ^{*} \to \ \mathit{fission}.</math>
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| The results indicated that nuclei of unbinilium were produced at high (~70 MeV) excitation energy which underwent fission with measurable half-lives > 10<sup>−18</sup> s. Although very short, the ability to measure such a process indicates a strong shell effect at Z=120. At lower excitation energy (see neutron evaporation), the effect of the shell will be enhanced and ground-state nuclei can be expected to have relatively long half-lives. This result could partially explain the relatively long half-life of <sup>294</sup>[[ununoctium|Uuo]] measured in experiments at Dubna. Similar experiments have indicated a similar phenomenon at Z=124 (see [[unbiquadium]]) but not for [[flerovium]], suggesting that the next proton shell does in fact lie at Z>120.<ref>{{cite journal|doi=10.1103/Physics.1.12|title=How stable are the heaviest nuclei?|year=2008|author=Natowitz, Joseph|journal=Physics|volume=1|pages=12|bibcode = 2008PhyOJ...1...12N }}</ref><ref>{{cite journal|journal=Phys. Rev. Lett.|volume=101|year=2008|page=072701|title=Fission Time Measurements: A New Probe into Superheavy Element Stability|doi=10.1103/PhysRevLett.101.072701|pmid=18764526|bibcode=2008PhRvL.101g2701M|issue=7|last1=Morjean|first1=M.|last2=Jacquet|first2=D.|last3=Charvet|first3=J.|last4=l’Hoir|first4=A.|last5=Laget|first5=M.|last6=Parlog|first6=M.|last7=Chbihi|first7=A.|last8=Chevallier|first8=M.|last9=Cohen|first9=C.|display-authors=8}}</ref>
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| ==Future reactions==
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| The team at RIKEN have begun a program utilizing <sup>248</sup>Cm targets and have indicated future experiments to probe the possibility of Z=120 being the next magic number using the aforementioned nuclear reactions to form <sup>302</sup>Ubn.<ref>see slide 11 in [http://www-win.gsi.de/tasca07/contributions/TASCA07_Contribution_Morita.pdf Future Plan of the Experimental Program on Synthesizing the Heaviest Element at RIKEN]</ref>
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| ==Calculated decay characteristics==
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| In a [[quantum tunneling]] model with mass estimates from a macroscopic-microscopic model, the [[alpha decay|alpha-decay]] half-lives of several [[isotope]]s of unbinilium (namely, <sup>292–304</sup>Ubn) have been predicted to be around 1–20 microseconds.<ref name=half-lifesall>{{cite journal|journal=Phys. Rev. C|volume=73|pages=014612|year=2006|title=α decay half-lives of new superheavy elements|author=P. Roy Chowdhury, C. Samanta, and D. N. Basu|doi=10.1103/PhysRevC.73.014612|bibcode=2006PhRvC..73a4612C|arxiv = nucl-th/0507054 }}</ref><ref>{{cite journal| journal=Nucl. Phys. A|volume=789|pages=142–154|year=2007| title=Predictions of alpha decay half lives of heavy and superheavy elements|author=Samanta, C.; Chowdhury, P. Roy and Basu, D.N. |doi=10.1016/j.nuclphysa.2007.04.001|bibcode=2007NuPhA.789..142S|arxiv = nucl-th/0703086 }}</ref><ref>{{cite journal|journal=Phys. Rev. C|volume=77|page=044603|year=2008|title=Search for long lived heaviest nuclei beyond the valley of stability|author=Chowdhury, P. Roy; Samanta, C. and Basu, D. N. |doi=10.1103/PhysRevC.77.044603|bibcode=2008PhRvC..77d4603C|issue=4|arxiv = 0802.3837 }}</ref><ref>{{cite journal|journal=At. Data & Nucl. Data Tables |volume=94|pages=781–806|year=2008|title=Nuclear half-lives for α-radioactivity of elements with 100 ≤ Z ≤ 130|author=Chowdhury, P. Roy; Samanta, C. and Basu, D. N. |doi=10.1016/j.adt.2008.01.003|bibcode=2008ADNDT..94..781C|issue=6|arxiv = 0802.4161 }}</ref>
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| ==Extrapolated chemical properties==
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| Unbinilium should be highly reactive, according to periodic trends, as this element is in the same periodic table column as the [[alkaline earth metals]]. It would be much more reactive than any other lighter elements of this group. If group reactivity is followed, this element would react violently in air to form an oxide (UbnO), in water to form the hydroxide, which would be a strong [[base (chemistry)|base]] and highly explosive in terms of flammability, and with the [[halogen]]s to form salts (such as UbnCl<sub>2</sub>).<ref name="emsley">{{cite book|last=Emsley|first=John|title=Nature's Building Blocks: An A-Z Guide to the Elements|edition=New|year=2011|publisher=Oxford University Press|location=New York, NY|isbn=978-0-19-960563-7|page=586}}</ref>
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| Although unbinilium is expected to behave typically for an alkaline earth metal, showing a strong +2 [[oxidation state]], the energetic properties of its [[valence electron]]s would increase its [[ionization energy|ionization energies]]; hence, unbinilium may have a lower [[metallic radius|metallic]] and [[ionic radius]] than expected, and may behave more similarly to [[calcium]] and [[strontium]] than [[barium]] or [[radium]].<ref name=EB>{{cite web|author=Seaborg|url=http://www.britannica.com/EBchecked/topic/603220/transuranium-element|title=transuranium element (chemical element)|publisher=Encyclopædia Britannica|date=c. 2006|accessdate=2010-03-16}}</ref> Unbinilium is also predicted to be the first alkaline earth metal to display the +4 oxidation state, due to the ionization energy of the 7p<sub>3/2</sub> electrons, which is predicted to be very low.<ref name=Haire/> The +1 state may also be stable in isolation.<ref name=Thayer/>
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| ==Target-projectile combinations leading to Z=120 compound nuclei==
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| The below table contains various combinations of targets and projectiles which could be used to form compound nuclei with an atomic number of 120.
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| {|class="wikitable" style="text-align:center"
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| ! Target !! Projectile !! CN !! Attempt result
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| !<sup>208</sup>Pb
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| |<sup>88</sup>Sr||<sup>296</sup>Ubn||{{unk|Reaction yet to be attempted<ref name=Haire/>}}
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| |-
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| !<sup>238</sup>U
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| |<sup>64</sup>Ni||<sup>302</sup>Ubn||{{no|Failure to date, σ < 94 fb}}
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| |-
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| !<sup>244</sup>Pu
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| |<sup>58</sup>Fe||<sup>302</sup>Ubn||{{no|Failure to date, σ < 0.4 pb}}
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| |-
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| !<sup>248</sup>Cm
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| |<sup>54</sup>Cr||<sup>302</sup>Ubn||{{no|Failure to date, not all details available}}
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| |-
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| !<sup>250</sup>Cm
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| |<sup>54</sup>Cr||<sup>304</sup>Ubn||{{unk|Reaction yet to be attempted}}
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| |-
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| !<sup>249</sup>Cf
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| |<sup>50</sup>Ti||<sup>299</sup>Ubn||{{unk|Results are not yet available}}
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| |-
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| !<sup>252</sup>Cf
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| |<sup>50</sup>Ti||<sup>302</sup>Ubn||{{unk|Reaction yet to be attempted}}
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| |-
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| !<sup>257</sup>Fm
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| |<sup>48</sup>Ca||<sup>305</sup>Ubn||{{unk|Reaction yet to be attempted}}
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| |}<!--please use {{yes|Successful reaction}} for successes, thanks-->
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| ==Theoretical calculations on evaporation cross sections==
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| The below table contains various targets-projectile combinations for which calculations have provided estimates for cross section yields from various neutron evaporation channels. The channel with the highest expected yield is given.
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| MD = multi-dimensional; DNS = dinuclear system; AS = advanced statistical; σ = cross section
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| {|class=wikitable style=text-align:center
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| |-
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| ! Target !! Projectile !! CN !! Channel (product) !! ~σ<sub>max</sub> !! Model !! Ref
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| |-
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| !<sup>208</sup>Pb
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| |<sup>88</sup>Sr||<sup>296</sup>Ubn||1n (<sup>295</sup>Ubn)||70 fb||DNS||<ref name=FengColdFusion>{{cite journal|arxiv=0707.2588|doi=10.1103/PhysRevC.76.044606|title=Formation of superheavy nuclei in cold fusion reactions|year=2007|author=Feng, Zhao-Qing|journal=Physical Review C|volume=76|pages=044606|last2=Jin|first2=Gen-Ming|last3=Li|first3=Jun-Qing|last4=Scheid|first4=Werner|bibcode=2007PhRvC..76d4606F|issue=4}}</ref>
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| |-
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| !<sup>208</sup>Pb
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| |<sup>87</sup>Sr||<sup>295</sup>Ubn||1n (<sup>294</sup>Ubn)||80 fb||DNS||<ref name=FengColdFusion />
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| |-
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| !<sup>208</sup>Pb
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| |<sup>88</sup>Sr||<sup>296</sup>Ubn||1n (<sup>295</sup>Ubn) ||<0.1 fb||MD||<ref name=ZG>{{cite journal|arxiv=0807.2537|doi=10.1103/PhysRevC.78.034610|title=Synthesis of superheavy nuclei: A search for new production reactions|year=2008|journal=Physical Review C|volume=78|pages=034610|author=Zagebraev, V; Greiner, W|bibcode=2008PhRvC..78c4610Z|issue=3}}</ref>
| |
| |-
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| !<sup>238</sup>U
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| |<sup>64</sup>Ni||<sup>302</sup>Ubn||3n (<sup>299</sup>Ubn) ||3 fb||MD||<ref name=ZG />
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| |-
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| !<sup>238</sup>U
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| |<sup>64</sup>Ni||<sup>302</sup>Ubn||2n (<sup>300</sup>Ubn)||0.5 fb||DNS||<ref name=FengHotFusion>{{cite journal|arxiv=0803.1117|doi=10.1016/j.nuclphysa.2008.11.003|title=Production of heavy and superheavy nuclei in massive fusion reactions|year=2009|author=Feng, Z|journal=Nuclear Physics A|volume=816|pages=33|last2=Jin|first2=G|last3=Li|first3=J|last4=Scheid|first4=W|bibcode=2009NuPhA.816...33F}}</ref>
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| |-
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| !<sup>238</sup>U
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| |<sup>64</sup>Ni||<sup>302</sup>Ubn||4n (<sup>298</sup>Ubn)||2 ab||DNS-AS||<ref name=Nasirov120>{{cite journal|arxiv=0812.4410|doi=10.1103/PhysRevC.79.024606|title=Quasifission and fusion-fission in reactions with massive nuclei: Comparison of reactions leading to the Z=120 element|year=2009|author=Nasirov, A. K.|journal=Physical Review C|volume=79|pages=024606|last2=Giardina|first2=G.|last3=Mandaglio|first3=G.|last4=Manganaro|first4=M.|last5=Hanappe|first5=F.|last6=Heinz|first6=S.|last7=Hofmann|first7=S.|last8=Muminov|first8=A.|last9=Scheid|first9=W.|bibcode = 2009PhRvC..79b4606N|issue=2|display-authors=9 }}</ref>
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| |-
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| !<sup>244</sup>Pu
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| |<sup>58</sup>Fe||<sup>302</sup>Ubn||4n (<sup>298</sup>Ubn) ||5 fb||MD||<ref name=ZG />
| |
| |-
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| !<sup>244</sup>Pu
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| |<sup>58</sup>Fe||<sup>302</sup>Ubn||3n (<sup>299</sup>Ubn)||8 fb||DNS-AS||<ref name=Nasirov120 />
| |
| |-
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| !<sup>248</sup>Cm
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| |<sup>54</sup>Cr||<sup>302</sup>Ubn||3n (<sup>299</sup>Ubn)||10 pb||DNS-AS||<ref name=Nasirov120 />
| |
| |-
| |
| !<sup>248</sup>Cm
| |
| |<sup>54</sup>Cr||<sup>302</sup>Ubn||4n (<sup>298</sup>Ubn) ||30 fb||MD||<ref name=ZG />
| |
| |-
| |
| !<sup>249</sup>Cf
| |
| |<sup>50</sup>Ti||<sup>299</sup>Ubn||4n (<sup>295</sup>Ubn) ||45 fb||MD||<ref name=ZG />
| |
| |-
| |
| !<sup>249</sup>Cf
| |
| |<sup>50</sup>Ti||<sup>299</sup>Ubn||3n (<sup>296</sup>Ubn) ||40 fb||MD||<ref name=ZG />
| |
| |-
| |
| !<sup>257</sup>Fm
| |
| |<sup>48</sup>Ca ||<sup>305</sup>Ubn||3n (<sup>302</sup>Ubn)||70 fb||DNS||<ref name=FengHotFusion />
| |
| |}
| |
| | |
| ==See also==
| |
| *[[Island of stability]]: [[flerovium]]–'''unbinilium'''–[[unbihexium]]
| |
| *[[Radium]]
| |
| *[[Barium]]
| |
| | |
| ==References==
| |
| {{clear}}
| |
| {{Reflist|colwidth=30em}}
| |
| | |
| {{Compact extended periodic table}}
| |
| | |
| [[Category:Chemical elements]]
| |
| [[Category:Hypothetical chemical elements]]
| |
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