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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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  • 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 I find Ziva pretty tough though at full merciless hollowfang iron A good hit with either
  • 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
  • Which rifle is the best? Kiloton Radium Rifle, Overseer . . . - Reddit
    Personal I’ll go with the Kiloton rifle, the overseers guardian is nice but one shotting everything kinda makes gun fights too easy You also forgot the con on the radium rifle where they fucked the recoil on automatic mode Also it makes sense that you’ll need perks to mod, idk why you think that’s a con?
  • Exception of type Curse. Radium. InstallManagement . . . - Reddit
    hi, I'm trying to upload a modpack in CurseForge, but it's repeating the same error: "Exception of type 'Curse Radium InstallManagement InstallTaskFailedException' was thrown " can anyone help me?
  • 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
  • Are radium PCs legit?? : r pcmasterrace - Reddit
    Welcome to the official subreddit of the PC Master Race PCMR! All PC-related content is welcome, including build help, tech support, and any doubt one might have about PC ownership You don't necessarily need a PC to be a member of the PCMR You just have to love PCs It's not about the hardware in your rig, but the software in your heart! Join us in celebrating and promoting tech, knowledge
  • 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 Radium Rifles good? : r fo76 - Reddit
    Radium Rifle has a far less reach and is more situational You reach a point where the Radiation part of the gun isn't that beneficial when fighting Humans cause regular bullets will work as good
  • Help me understand risk factors with radium clocks; Antique store . . .
    Radium paint without cover is a big no no - the paint can and will flake and subsequently contaminate whoever touches it and its surroundings Radium always carries a radon contamination risk A disassembled watch clock or other type of device shouldn't be kept in the open, or even handled without PPE Sure Radium won't kill you outright but since it's acting chemically similar to calcium and
  • Is The Radium Rifle Worth Using? : r fo4 - Reddit
    I Just Got The Legendary Never Ending Radium Rifle From A Legendary Super Mutant,And I Wonder If That Gun Is Worth Using Or Not Archived post New comments cannot be posted and votes cannot be cast





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