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radium    音标拼音: [r'ediəm]
n. 镭



radium
n 1: an intensely radioactive metallic element that occurs in
minute amounts in uranium ores [synonym: {radium}, {Ra},
{atomic number 88}]

Radium \Ra`di*um\ (r[=a]"d[i^]*[u^]m), n. [NL., fr. L. radius
ray.] (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 {radon}.

Note: Radium preparations are remarkable for maintaining
themselves at a higher temperature than their
surroundings, and for their radiations, which are of
three kinds: alpha rays, beta rays, and gamma rays (see
these terms). The beta and gamma rays seen in radium
preparations are in fact due to disintegration of decay
products of radium rather than the radium itself. By
reason of these rays they ionize gases, affect
photographic plates, cause sores on the skin, and
produce many other striking effects. Their degree of
activity depends on the proportion of radium present,
but not on its state of chemical combination or on
external conditions. The radioactivity of radium is
therefore an atomic property, and is due to an inherent
instability of the atomic nucleus which causes its
decay in a process whose rate is first order. The
disintegration of the radium nucleus is only the first
in a series of nuclear disintegrations leading to
production of a series of elements and isotopes. The
chain has at least seven stages; the successive main
products have been studied and are {radon}, a gaseous
radioactive element belonging chemically to the inert
noble gas series (originally called radium emanation or
exradio, radium A, radium B, radium C, etc. The
successive products are unstable isotopes of several
different elements, each with an atomic weight a little
lower than its predecessor. Lead is the stable end
product. At the same time, the light gas helium is
formed, being generated when the expelled alpha
particles (positively charged helium nuclei) acquire
electrons. Radium, in turn, is formed in the
pitchblende ore by a slow disintegration of uranium.
Natural radium and also an isotope (radium-228, also
called mesothorium I) formed by the decay of thorium,
were at one time used to make a luminous paint for
watch dials, until the danger of the radioactivity
became fully appreciated, and use of such material in
watches was discontinued. See also {mesothorium}.
[Webster 1913 Suppl. PJC]

45 Moby Thesaurus words for "radium":
acid, actual cautery, americium, astatine, atomic cocktail,
berkelium, brand, brand iron, branding iron, caustic, cauter,
cauterant, cauterizer, cautery, cobalt, corrosive, curium,
einsteinium, electrocautery, escharotic, fermium, francium,
hahnium, hot iron, lunar caustic, mendelevium, mordant, moxa,
neptunium, plutonium, polonium, potential cautery, promethium,
protactinium, radiocalcium, radiocarbon, radioelement, radioiodine,
radioisotope, radiosodium, radon, tagged element, technetium,
tracer, uranium

radium
Symbol: Ra
Atomic number: 88
Atomic weight: (226)
Radioactive metallic transuranic element, belongs to group 2 of the
periodic table. Most stable isotope, Ra-226 has a half-life of 1602
years,
which decays into radon. Isolated from pitchblende in 1898 Marie and
Pierre Curie.


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  • Be very careful with radium (radioactive lume) in old watches. . . its . . .
    The deteriorating radium lume is essentially a loose radioactive dust emitter and is illegal to ship even under this threshold Around half of the packages I've received containing radium are over this legal threshold and so were sent illegally at a danger to everyone who came in contact with the box
  • Who can explain me this error ? : r CurseForge - Reddit
    I just wanted to create a new modfolder with curseforge with the 1 20 1 version Exception of type 'Curse Radium InstallManagement InstallTaskFailedException' was thrown
  • Are there downsides to installing A LOT of performance mods?
    Radium was less performant and I suffered alot of crashes with radium in the callstack and noticed quite a few broken mods The most apparent was the YUNGs better ender island Which radium somehow caused the ender dragon to instantly die and broke the fight Also Radium hasnt been updated since october 2023 as of writing this
  • Why don’t we use Radium instead of uranium in nuclear power . . . - Reddit
    Radium isn't fissile (or at least most isotopes of radium aren't fissile) The very basic way that a nuclear reactor works is this a fissile isotope (like uranium-235, plutonium-239, or uranium-233) absorbs a neutron and has a chance of undergoing fission, if it does undergo fission it releases a lot of energy and between 2-3 new neutrons which can cause more fissions Many isotopes are
  • Eben Byers: The Man Who Drank Radioactive Water Until His Jaw . . . - Reddit
    Radium jaw Radium jaw, or radium necrosis, is a historic occupational disease brought on by the ingestion and subsequent absorption of radium into the bones of radium dial painters It also affected those consuming radium-laden patent medicines
  • Eben Byers: The Man who Drank Radioactive Water - Reddit
    Radium, being very chemically similar to calcium, gets taken up in the bones, which kills the cells there (because the radiation causes enough damage to the cell's DNA that they basically commit suicide, which is a way the body protects against cancer) As the bones stop growing, they only accumulate damage and break down
  • Please check our performance mods! : r feedthebeast - Reddit
    The subreddit for all things related to Modded Minecraft for Minecraft Java Edition --- This subreddit was originally created for discussion around the FTB launcher and its modpacks but has since grown to encompass all aspects of modding the Java edition of Minecraft The r feedthebeast subreddit is not affiliated or associated with the Feed the Beast company
  • Radium alloy scarcity : r vrising - Reddit
    It feels like attempting to acquire radium alloy in the current game without just fighting Ziva the Engineer is just a fool's errand Initial recipes require 8 radium alloy, but you can utterly clear the one area marked with radium in the Gloomhaven South and wind up with 1-2 radium alloy for the effort
  • Is It Safe to Wear a Radium Watch? : r Radiation - Reddit
    The most serious concern about wearing a radium watch would be if the crystal were to break, or if the seal was poorly maintained allowing radium containing paint particles to be released where they could cause contamination, be inhaled, or ingested through your mouth
  • Raydium vs Jupiter, which one do you prefer and why? : r solana - Reddit
    Which one do you prefer? Seeing both pumping a lot today I have read a lot of comments of people saying Raydium is slow, but that doesn't seem to affect price much





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