from The American Heritage® Dictionary of the English Language, 5th Edition.
- noun A rare, brilliant white, luminescent, highly radioactive metallic element found in very small amounts in uranium ores, having more than 40 isotopes and isomers with mass numbers between 201 and 234, of which Ra-226 with a half-life of 1,600 years is the most common. It is used in cancer radiotherapy, as a neutron source for some research purposes, and formerly as a constituent of luminescent paints. Atomic number 88; melting point 696°C; boiling point 1,737°C; specific gravity 5; valence 2. cross-reference: Periodic Table.
from The Century Dictionary.
- noun A chemical element of very remarkable character, discovered in 1898 by Mme. Sklodowska Curie, working with her husband and M. Bémont.
from the GNU version of the Collaborative International Dictionary of English.
- noun (Chem.) An intensely radioactive metallic element found (combined) in minute quantities in pitchblende, and various other uranium minerals. Symbol, Ra; atomic weight, 226.4. Radium was discovered by M. and Mme. Curie, of Paris, who in 1902 separated compounds of it by a tedious process from pitchblende. Its compounds color flames carmine and give a characteristic spectrum. It is divalent, resembling barium chemically. The main isotope of radium found in pitchblende, radium-226, has a half-life of 1620 years, decaying first by alpha emission to
from Wiktionary, Creative Commons Attribution/Share-Alike License.
- noun a radioactive metallic chemical element (symbol Ra) with an
atomic numberof 88.
from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.
- noun an intensely radioactive metallic element that occurs in minute amounts in uranium ores
from The American Heritage® Dictionary of the English Language, 4th Edition
from Wiktionary, Creative Commons Attribution/Share-Alike License
Slowly the uranium changes into radium, the radium changes into a gas called the radium emanation, and that again to what we call radium A, and so the process goes on, giving out energy at every stage, until at last we reach the last stage of all, which is, so far as we can tell at present, lead.
Having previously identified a new radioactive element, which they named polonium in honor of Marie's Polish origins, they have stumbled upon a second, which they called radium.
They proposed to involve him in radium research by using his laboratory either under his or Haitinger's directorship.
At the same time, those involved in radium research came to consider themselves as a distinct disciplinary community.
The interest in radium for medical use was so great that radium preparations and apparatus to produce radioactive water quickly became commercially available in Vienna.
Open to medical practitioners, it further functioned as an intermediate space of collaboration between physicists and physicians for the development and improvement of methods applied in radium therapy.
The market price of radium is at present 70 dollars for 1 mg, but I am sure that our academy would be willing to accept a lower price. 142
In both chapters 2 and 3, radium is shown to be a trafficking material that defined individual and institutional partnerships, the urban construction and architectural design of science buildings, and the exchanges of knowledge, instruments, and expertise.
In 1911, a protocol for trade in radium preparations and a provisional plan for the function of the Radiumstation at the Allgemeines Krankenhaus were signed at the Radium Institute. 54 Shortly afterwards and on several occasions, radium was prepared at the Radium
He expressed an early and strong interest in radium research and when the International Radium Standards Committee was founded in 1910, Meyer was appointed its secretary, an indication of his scientific success.