| 释义 |
isotone Physics.|ˈaɪsəʊtəʊn|
[a. F. isotone (K. Guggenheimer 1934, in Jrnl. de Physique et le Radium V. 253), coined by replacing the p of isotope (the initial letter of proton) by n for neutron.]
Each of two or more nuclides having the same number of neutrons (but usually different numbers of protons).
1934Sci. Abstr. A. XXXVII. 734 It is proposed that elements having the same number of neutrons, but different atomic numbers shall be termed ‘isotones’. 1952Sci. News XXIII. 39 There is an exceptionally large number of nuclei all containing 20 protons (isotopes of calcium)... Nuclei containing 20, 50 or 82 neutrons also have a large number of isotones. 1966[see isobar 2]. 1972Physics Bull. Mar. 148/3 The isotone shift differs from the isotope shifts in that the former measures the energy difference of atoms when protons are added to the nucleus with the number of neutrons remaining the same, whereas for the latter the role of protons and neutrons are reversed. The study of isotope as well as isotone shifts reveal the nuclear shell structure. |