actinium


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ac·tin·i·um

 (ăk-tĭn′ē-əm)
n. Symbol Ac
A radioactive element found in uranium ores, used in equilibrium with its decay products as a source of alpha rays. Its longest lived isotope is Ac-227 with a half-life of 21.77 years. Atomic number 89; melting point 1,050°C; boiling point 3,198°C; specific gravity (calculated) 10.07; valence 3. See Periodic Table.
[From Greek aktīs, aktīn-, ray (from its radioactivity); see nekw-t- in Indo-European roots.]
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.

actinium

(ækˈtɪnɪəm)
n
(Elements & Compounds) a radioactive element of the actinide series, occurring as a decay product of uranium. It is used as an alpha-particle source and in neutron production. Symbol: Ac; atomic no: 89; half-life of most stable isotope,227Ac: 21.6 years; relative density: 10.07; melting pt: 1051°C; boiling pt: 3200 ± 300°C
[C19: New Latin, from actino- + -ium]
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014

ac•tin•i•um

(ækˈtɪn i əm)

n.
a radioactive, silver-white, metallic element that glows blue in the dark, resembling the rare earths in chemical behavior and valence. Symbol: Ac; at. no.: 89; at. wt.: 227.
[< French (1900); see actino-, -ium2]
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.

ac·tin·i·um

(ăk-tĭn′ē-əm)
Symbol Ac A silvery-white, highly radioactive metallic element of the actinide series that is found in uranium ores. It is about 150 times more radioactive than radium and is used as a source of alpha rays. Its most stable isotope has a half-life of about 22 years. Atomic number 89. See Periodic Table.
The American Heritage® Student Science Dictionary, Second Edition. Copyright © 2014 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
ThesaurusAntonymsRelated WordsSynonymsLegend:
Noun1.actinium - a radioactive element of the actinide seriesactinium - a radioactive element of the actinide series; found in uranium ores
Ac, atomic number 89
chemical element, element - any of the more than 100 known substances (of which 92 occur naturally) that cannot be separated into simpler substances and that singly or in combination constitute all matter
uranium ore - any ore from which uranium can be extracted
Based on WordNet 3.0, Farlex clipart collection. © 2003-2012 Princeton University, Farlex Inc.
Translations
актиний
actinium
actinium
aktiinium
aktinium
aktinij
aktínium
aktín
アクチニウム
actinium
aktinis
actinium
aktyn
actiniu
aktinij
aktinium
aktinyum

actinium

[ækˈtɪnɪəm] N → actinio m
Collins Spanish Dictionary - Complete and Unabridged 8th Edition 2005 © William Collins Sons & Co. Ltd. 1971, 1988 © HarperCollins Publishers 1992, 1993, 1996, 1997, 2000, 2003, 2005
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References in periodicals archive ?
27 December 2012 - US biopharmaceutical firm Actinium Pharmaceuticals Inc said it had closed the first tranche, worth USD5.1m (EUR3.8m), of its current common stock offering.
Actinium wraps up USD5.1m first tranche of stock placement
Dr Almaula joins Actinium with significant experience in the targeted radiotherapy field, having most recently worked as head, Business Development at Advanced Accelerator Applications Inc.
Actinium Pharmaceuticals names new chief business officer
Schaffer offers the example of metal actinium, whose isotope 225Ac has demonstrated the potential to kill cancerous tumours, although it would need to be employed in combination with biochemical agents that could prevent it from accumulating in other parts of the body.
TRIUMF ramps up rare isotope output with ARIEL
Alphabetically, actinium is the first in the list of what?
Quiz of the Day
To increase drug potency lintuzumab was conjugated to radionuclides as, for example, actinium ([sup.225]Ac), bismuth ([sup.231]Bi), or iodine (I-131), with promising results in AML patients [105-107].
Target therapy in hematological malignances: new monoclonal antibodies
Thorium is radioactive element decayed very slowly compared to many other radioactive materials (half-life of [sup.223]Th is 1.405 x [10.sup.10] year) to produces a radioactive gas, radon-220, radium and actinium and emits alpha particles which can be breathed in and swallowed.
Thorium removal from waste water using banana peel and employment of waste residue
Properties of four natural decay series of actinides [2] Series Initial Half-life, Stable nuclide years endmember Thorium [sup.232]Th 1.405 x [10.sup.10] [sup.208]Pb Neptunium [sup.237]Np 2.140 x [10.sup.6] [sup.209]Bi Uranium [sup.238]U 4.470 x [10.sup.9] [sup.206]Pb Actinium [sup.235]U 7.038 x [10.sup.8] [sup.207]Pb Table 2.
Technology for the removal of radionuclides from natural water and waste management: state of the art/Tehnoloogia radionukliidide eraldamiseks veest ja jaatmekaitlus
27 December 2012 a[euro]" US biopharmaceutical firm Actinium Pharmaceuticals Inc said it had closed the first tranche, worth USD5.1m (EUR3.8m), of its current common stock offering.
Actinium wraps up USD5.1m first tranche of stock placement
A fast reactor's ability to fission all actinides (actinium and heavier elements), makes it theoretically possible to repeatedly separate those materials from spent fuel and feed them back into the reactor until they are entirely fissioned.
Managing the nuclear fuel cycle: policy implications of expanding global access to nuclear power
For instance, Actinium has the oxidation order +3, while Uranium --only +3, +4, +5, and +6.
The upper limit of the periodic table of elements points out to the "long" version of the table, instead of the "short" one
About 55% of this quantity is from gamma rays emitted by terrestrial radon; 8% is from cosmic ray; the natural radioactivity of environmental rocks (composed of such radionuclides as uranium, actinium, radium and thorium) and the absorbed dose from internal sources (Klement et al.
Environmental ionizing radiation distribution in Rivers State, Nigeria/Aplinkos jonizuojancios spinduliuotes pasiskirstymas Rivers valstijoje, Nigerijoje/[TEXT NOT REPRODUCIBLE IN ASCII]

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