Cannabaceae

Isotopes of titanium (22Ti)
Main isotopes[1] Decay
abun­dance half-life (t1/2) mode pro­duct
44Ti synth 59.1 y ε 44Sc
46Ti 8.25% stable
47Ti 7.44% stable
48Ti 73.7% stable
49Ti 5.41% stable
50Ti 5.18% stable
Standard atomic weight Ar°(Ti)

Naturally occurring titanium (22Ti) is composed of five stable isotopes; 46Ti, 47Ti, 48Ti, 49Ti and 50Ti with 48Ti being the most abundant (73.8% natural abundance). Twenty-one radioisotopes have been characterized, with the most stable being 44Ti with a half-life of 60 years, 45Ti with a half-life of 184.8 minutes, 51Ti with a half-life of 5.76 minutes, and 52Ti with a half-life of 1.7 minutes. All of the remaining radioactive isotopes have half-lives that are less than 33 seconds, and the majority of these have half-lives that are less than half a second.[4]

The isotopes of titanium range in atomic mass from 39.00 u (39Ti) to 64.00 u (64Ti). The primary decay mode for isotopes lighter than the stable isotopes (lighter than 46Ti) is β+ and the primary mode for the heavier ones (heavier than 50Ti) is β; their respective decay products are scandium isotopes and the primary products after are vanadium isotopes.[4]

List of isotopes

[edit]
Nuclide
[n 1]
Z N Isotopic mass (Da)
[n 2][n 3]
Half-life
[n 4]
Decay
mode

[n 5]
Daughter
isotope

[n 6]
Spin and
parity
[n 7][n 4]
Natural abundance (mole fraction)
Excitation energy Normal proportion Range of variation
39Ti 22 17 39.00161(22)# 31(4) ms
[31(+6-4) ms]
β+, p (85%) 38Ca 3/2+#
β+ (15%) 39Sc
β+, 2p (<.1%) 37K
40Ti 22 18 39.99050(17) 53.3(15) ms β+ (56.99%) 40Sc 0+
β+, p (43.01%) 39Ca
41Ti 22 19 40.98315(11)# 80.4(9) ms β+, p (>99.9%) 40Ca 3/2+
β+ (<.1%) 41Sc
42Ti 22 20 41.973031(6) 199(6) ms β+ 42Sc 0+
43Ti 22 21 42.968522(7) 509(5) ms β+ 43Sc 7/2−
43m1Ti 313.0(10) keV 12.6(6) μs (3/2+)
43m2Ti 3066.4(10) keV 560(6) ns (19/2−)
44Ti 22 22 43.9596901(8) 60.0(11) y EC 44Sc 0+
45Ti 22 23 44.9581256(11) 184.8(5) min β+ 45Sc 7/2−
46Ti 22 24 45.9526316(9) Stable 0+ 0.0825(3)
47Ti 22 25 46.9517631(9) Stable 5/2− 0.0744(2)
48Ti 22 26 47.9479463(9) Stable 0+ 0.7372(3)
49Ti 22 27 48.9478700(9) Stable 7/2− 0.0541(2)
50Ti 22 28 49.9447912(9) Stable 0+ 0.0518(2)
51Ti 22 29 50.946615(1) 5.76(1) min β 51V 3/2−
52Ti 22 30 51.946897(8) 1.7(1) min β 52V 0+
53Ti 22 31 52.94973(11) 32.7(9) s β 53V (3/2)−
54Ti 22 32 53.95105(13) 1.5(4) s β 54V 0+
55Ti 22 33 54.95527(16) 490(90) ms β 55V 3/2−#
56Ti 22 34 55.95820(21) 164(24) ms β (>99.9%) 56V 0+
β, n (<.1%) 55V
57Ti 22 35 56.96399(49) 60(16) ms β (>99.9%) 57V 5/2−#
β, n (<.1%) 56V
58Ti 22 36 57.96697(75)# 54(7) ms β 58V 0+
59Ti 22 37 58.97293(75)# 30(3) ms β 59V (5/2−)#
60Ti 22 38 59.97676(86)# 22(2) ms β 60V 0+
61Ti 22 39 60.98320(97)# 10# ms
[>300 ns]
β 61V 1/2−#
β, n 60V
62Ti 22 40 61.98749(97)# 10# ms 0+
63Ti 22 41 62.99442(107)# 3# ms 1/2−#
64Ti[5] 22 42 63.998410(640)# 5# ms
[>620 ns]
0+
This table header & footer:
  1. ^ mTi – Excited nuclear isomer.
  2. ^ ( ) – Uncertainty (1σ) is given in concise form in parentheses after the corresponding last digits.
  3. ^ # – Atomic mass marked #: value and uncertainty derived not from purely experimental data, but at least partly from trends from the Mass Surface (TMS).
  4. ^ a b # – Values marked # are not purely derived from experimental data, but at least partly from trends of neighboring nuclides (TNN).
  5. ^ Modes of decay:
    EC: Electron capture


    n: Neutron emission
    p: Proton emission
  6. ^ Bold symbol as daughter – Daughter product is stable.
  7. ^ ( ) spin value – Indicates spin with weak assignment arguments.

Titanium-44

[edit]

Titanium-44 (44Ti) is a radioactive isotope of titanium that undergoes electron capture to an excited state of scandium-44 with a half-life of 60 years, before the ground state of 44Sc and ultimately 44Ca are populated.[6] Because titanium-44 can only undergo electron capture, its half-life increases with ionization and it becomes stable in its fully ionized state (that is, having a charge of +22).[7]

Titanium-44 is produced in relative abundance in the alpha process in stellar nucleosynthesis and the early stages of supernova explosions.[8] It is produced when calcium-40 fuses with an alpha particle (helium-4 nucleus) in a star's high-temperature environment; the resulting 44Ti nucleus can then fuse with another alpha particle to form chromium-48. The age of supernovae may be determined through measurements of gamma-ray emissions from titanium-44 and its abundance.[7] It was observed in the Cassiopeia A supernova remnant and SN 1987A at a relatively high concentration, a consequence of delayed decay resulting from ionizing conditions.[6][7]

References

[edit]
  1. ^ Kondev, F. G.; Wang, M.; Huang, W. J.; Naimi, S.; Audi, G. (2021). "The NUBASE2020 evaluation of nuclear properties" (PDF). Chinese Physics C. 45 (3): 030001. doi:10.1088/1674-1137/abddae.
  2. ^ "Standard Atomic Weights: Titanium". CIAAW. 1993.
  3. ^ Prohaska, Thomas; Irrgeher, Johanna; Benefield, Jacqueline; Böhlke, John K.; Chesson, Lesley A.; Coplen, Tyler B.; Ding, Tiping; Dunn, Philip J. H.; Gröning, Manfred; Holden, Norman E.; Meijer, Harro A. J. (2022-05-04). "Standard atomic weights of the elements 2021 (IUPAC Technical Report)". Pure and Applied Chemistry. doi:10.1515/pac-2019-0603. ISSN 1365-3075.
  4. ^ a b Barbalace, Kenneth L. (2006). "Periodic Table of Elements: Ti - Titanium". Retrieved 2006-12-26.
  5. ^ Tarasov, O. B. (20 May 2013). "Production cross sections from 82 Se fragmentation as indications of shell effects in neutron-rich isotopes close to the drip-line". Physical Review C. 87 (5): 054612. arXiv:1303.7164. Bibcode:2013PhRvC..87e4612T. doi:10.1103/PhysRevC.87.054612.
  6. ^ a b Motizuki, Y.; Kumagai, S. (2004). "Radioactivity of the key isotope 44Ti in SN 1987A". AIP Conference Proceedings. 704 (1): 369–374. arXiv:astro-ph/0312620. Bibcode:2004AIPC..704..369M. CiteSeerX 10.1.1.315.8412. doi:10.1063/1.1737130. S2CID 1700673.
  7. ^ a b c Mochizuki, Y.; Takahashi, K.; Janka, H.-Th.; Hillebrandt, W.; Diehl, R. (2008). "Titanium-44: Its effective decay rate in young supernova remnants, and its abundance in Cas A". Astronomy and Astrophysics. 346 (3): 831–842. arXiv:astro-ph/9904378.
  8. ^ Fryer, C.; Dimonte, G.; Ellinger, E.; Hungerford, A.; Kares, B.; Magkotsios, G.; Rockefeller, G.; Timmes, F.; Woodward, P.; Young, P. (2011). Nucleosynthesis in the Universe, Understanding 44Ti (PDF). ADTSC Science Highlights (Report). Los Alamos National Laboratory. pp. 42–43.

One thought on “Cannabaceae

  1. Well, that’s interesting to know that Psilotum nudum are known as whisk ferns. Psilotum nudum is the commoner species of the two. While the P. flaccidum is a rare species and is found in the tropical islands. Both the species are usually epiphytic in habit and grow upon tree ferns. These species may also be terrestrial and grow in humus or in the crevices of the rocks.
    View the detailed Guide of Psilotum nudum: Detailed Study Of Psilotum Nudum (Whisk Fern), Classification, Anatomy, Reproduction

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