isotope

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isotope

 [i´so-tōp]
a chemical element having the same atomic number as another (i.e., the same number of nuclear protons), but having a different atomic mass (i.e., a different number of nuclear neutrons).
radioactive isotope radioisotope.
stable isotope one that does not transmute into another element with emission of corpuscular or electromagnetic radiations.

i·so·tope

(ī'sō-tōp), An isotope is identified by its symbol preceded by a superscript numeral showing its mass number (12C). Alternatively the mass number may follow the symbol at the same level (C 12). When the name of the element rather than its symbol is used, the numeral must follow and not precede the name (carbon 12). Do not join the numeral to the symbol or the name with a hyphen. The atomic number of an element (the unvarying number of protons in its nucleus) may be shown by a subscript numeral preceding the symbol 6C).
One of two or more nuclides that are chemically identical, having the same number of protons, yet differ in mass number, because their nuclei contain different numbers of neutrons; individual isotopes are names with the inclusion of their mass number in the superscript position (12C) and the atomic number (nuclear protons in the subscript position (6C). In former usage, the mass numbers follow the chemical symbol (C-12).
[iso- + G. topos, part, place]

isotope

/iso·tope/ (i´so-tōp) a chemical element having the same atomic number as another (i.e., the same number of nuclear protons), but having a different atomic mass (i.e., a different number of nuclear neutrons).

isotope

[ī′sətōp]
Etymology: Gk, isos + topos, place
one of two or more forms of an atom having the same number of protons in the atomic nucleus but different numbers of neutrons and thus a different atomic mass. For example, two common isotopes of carbon are 12C, which has six neutrons, and 14C, which has eight. Many isotopes are used in diagnostic and therapeutic procedures.

isotope

Imaging
An MRI term for atomic nuclei that contain the same number of protons, but differ in the number of neutrons in the nucleus of the atom for the element concerned.

i·so·tope

(ī'sŏ-tōp)
One of two or more nuclides that are chemically identical, having the same number of protons, yet differ in mass number, because their nuclei contain different numbers of neutrons; individual isotopes are named with the inclusion of their mass number in the superior position (12C) and the atomic number (nuclear protons) in the inferior position (6C).
[iso- + G. topos, part, place]

isotope

Chemically identical elements whose atomic nuclei have the same number of protons but different numbers of neutrons. The number of protons determines the number of orbital electrons and hence the chemical properties. Radioactive isotopes are called radionuclides. From the Greek iso -, equal and topos , place. Isotopes occupy the same place in the Periodic table of the elements.

isotope

any of the forms of an element having the same number of protons (atomic number) but a different number of neutrons (atomic mass). Some isotopes of an element may be radioisotopes (e.g. 12C is not radioactive while 14C is) and yet can function normally in biological material. Isotopes can thus be ‘tagged’ (using suitable detection devices such as geiger counters and autoradiography) as biochemical processes occur. See HALF-LIFE, AUTO RADIO GRAPH.

Isotope

An unstable form of an element that gives off radiation to become stable. Elements are characterized by the number of electrons around each atom. One electron's negative charge balances the positive charge of each proton in the nucleus. To keep all those positive charges in the nucleus from repelling each other (like the same poles of magnets), neutrons are added. Only certain numbers of neutrons work. Other numbers cannot hold the nucleus together, so it splits apart, giving off ionizing radiation. Sometimes one of the split products is not stable either, so another split takes place. The process is called radioactivity.

i·so·tope

(ī'sŏ-tōp)
One of two or more nuclides that are chemically identical, having the same number of protons, yet differ in mass number, because their nuclei contain different numbers of neutrons.
[iso- + G. topos, part, place]

isotope (ī´sōtōp),

n one of several nuclides having the same number of protons in their nuclei, and hence having the same atomic number but differing in the number of neutrons, and therefore in the mass number. The isotopes of a particular element have virtually identical chemical properties.
isotope, stable,
n a nonradioactive isotope of an element.

isotope

a chemical element having the same atomic number as another (i.e. the same number of nuclear protons), but having a different atomic mass (i.e. a different number of nuclear neutrons).

radioactive isotope
one having an unstable nucleus and which emits characteristic radiation during its decay to a stable form. See also radioisotope.
stable isotope
one that does not transmute into another element with emission of corpuscular or electromagnetic radiations.
References in periodicals archive ?
Mieux, on peut suggerer que les seuils deviennent des limites, a la fin des segments propres a une isotopie donnee.
Il ne reste pius, au niveau du recit, qu'a creer une double isotopie qui accueille le lecteur dans l'incipit, comme nous le montrerons pius loin, et a placer des traits descriptifs a posteriori pour que le conte soit lisible d'une maniere univoque.
Pourtant, comme nous le verrons pius tard, il y a une isotopie juive qui donne au texte une lecture fortement univoque, bien que cette derniere se cache, si l'on peut dire, derriere differents niveaux de narration.
In Anghel's choreographic adaptation, these major thematic isotopies from Shakespeare's text enable the subsuming of the kinesic figures under two predicative isotopies by means of these, two distinct actantial categories, the adjuvant and the opponent, are manifested.
When such binary oppositions are connected with their governing isotopies and with the outcome of the tale's action, it becomes evident that certain values prevail in this fictional world over their contraries: certain types of pleasure over work and certain forms of knowledge over ignorance.
Of the four isotopies that govern both major parts of the plot Love, Dissimulation, Degradation, and Retribution - Dissimulation appears either explicitly or implicitly most often.
The result of such an application of a theoretical model to a particular narrative may be to provide insights not only into the absences, say, of a character, marked in this case by the exceptional asymmetry as determined by a comparison to the ruling symmetry, but also to reveal implied ruling isotopies, which otherwise may have remained hidden from the interpreter.
D'abord, peut-etre, en emaillant le recit de notations ou de peripeties propres a y introduire une isotopie de l'irrationnel -- voire, asymptotiquement, du fantastique -- qui le soustrait en partie au systeme de l'illusion realiste pour le rattacher a une autre forme (generiquement determinee) de vraisemblable.
Frederic demonstrates the crucial importance of the link between form of content and form of expression, and the way it ultimately allows an opening towards a historical and ideological dimension without falling into aesthetic subjectivism, by examining two key forms: enumeration (where Frederic draws particularly on her excellent earlier work on Saint-John Perse) and isotopy (a plea for an extension of the latter to syntactical isotopies being one of Frederic's most interesting contributions).
Du point de vue rhetorique, cette dualite permet la cohabitation, et meme la juxtaposition, de deux isotopies.