actinium

Definitions

  • WordNet 3.6
    • n actinium a radioactive element of the actinide series; found in uranium ores
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Webster's Revised Unabridged Dictionary
    • n Actinium (Chem) A supposed metal, said by Phipson to be contained in commercial zinc; -- so called because certain of its compounds are darkened by exposure to light.
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Century Dictionary and Cyclopedia
    • n actinium A supposed chemical element found associated with zinc. Its chemical and physical properties have not been fully investigated.
    • n actinium A radioactive substance found by Debierne to exist in the residues remaining from pitchblende after the extraction of the uranium: a new radio-element closely related in its chemical behavior to lanthanum, from which it has not as yet been found possible to separate it completely. It has not been obtained in a state of sufficient purity to give any characteristic spectrum and is identified and recognized entirely by its radioactive properties. Actinium itself has not been found to emit a radiation but undergoes disintegration with the formation of a series of radioactive products known as radioactinium, axtinium-X, actinium emanation, actinium A, actinium B, and actinium C. Of these, the first, second, third, and fifth emit alpha-rays, the fourth beta-rays, and the sixth beta- and gamma-rays (see obscure rays). These products are present in all ordinary actinium preparations. The occurrence of actinium indicates that it is a disintegration product of uranium, although its genetic relationship to ionium and radium has not yet been established. Actinium is identical with the emanium of Giesel. See emanation.
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Etymology

Webster's Revised Unabridged Dictionary
Gr. , , ray

Usage

In literature:

The actinium is present in negligibly small amounts.
"The Birth-Time of the World and Other Scientific Essays" by J. (John) Joly
In this class are now placed also the three radio-active gases, emanating respectively from radium, thorium, and actinium.
"A Brief Account of Radio-activity" by Francis Preston Venable
ACTINIUM, an element or elementary substance obtained in minute quantities in connection with the study of radioactivity.
"The New Gresham Encyclopedia. Vol. 1 Part 1" by Various
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In science:

An active source of actinium was covered with a sheet of mica and placed in a chamber.
Discovery of the thallium, lead, bismuth, and polonium isotopes
Discovery of actinium, thorium, protactinium, and uranium isotopes.
Discovery of the actinium, thorium, protactinium, and uranium isotopes
On-line alpha spectroscopy of neutron-deficient actinium isotopes” .
Discovery of the actinium, thorium, protactinium, and uranium isotopes
Debierne is generally credited with the discovery of actinium.
Discovery of the actinium, thorium, protactinium, and uranium isotopes
An additional short-lived chain collateral to the actinium (4n+3) natural radioactive family has also been partially identified.
Discovery of the actinium, thorium, protactinium, and uranium isotopes
An additional short-lived chain collateral to the actinium (4n+3) natural radioactive family has also been partially identified.
Discovery of the actinium, thorium, protactinium, and uranium isotopes
Discovery of actinium, thorium, protactinium, and uranium isotopes.
Discovery of the actinium, thorium, protactinium, and uranium isotopes
Fig. 1: Original nomenclature of radon, radium, actinium, and thorium isotopes within the three natural occurring radioactive decay series.
Discovery of the astatine, radon, francium, and radium isotopes
An additional short-lived chain collateral to the actinium (4n+3) natural radioactive family has also been partially identified.
Discovery of the astatine, radon, francium, and radium isotopes
An additional short-lived chain collateral to the actinium (4n+3) natural radioactive family has also been partially identified.
Discovery of the astatine, radon, francium, and radium isotopes
ThX would not serve also to separate an analogous product from actinium.
Discovery of the astatine, radon, francium, and radium isotopes
This substance, which is so similar in properties to ThX, will be called actinium X (AcX).
Discovery of the astatine, radon, francium, and radium isotopes
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