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Research draft

europium

vr.tr.europium · PHY.MAT

Let an agent explain europium as an element and material, relay its properties, uses, supply and handling information from reference sources, and separate it from other rare earths and from its compounds.

Thing Registry Physical world and living systems

Research draft, second pass

A second pass drafted this model: the structure a model of this thing needs, and what is known about it in the world. The line under this one says how the second half was obtained - researched against sources, or recalled without web access, in which case nothing here was read anywhere and every claim is a lead to verify. Unreviewed either way.

written by Claude from model knowledge without web access - no source was read, every claim is a lead to verify

Researched by: Claude

Purpose and description

Let an agent explain europium as an element and material, relay its properties, uses, supply and handling information from reference sources, and separate it from other rare earths and from its compounds.

A soft silvery rare earth metal, chemical element 63 and a lanthanide, the most reactive of the rare earths, obtained from monazite and bastnasite; used in red and blue phosphors for displays, lighting and banknote security features, in nuclear control rods and in medical imaging agents.

What it is for: Phosphors, security features, control rods and research.

It can be explain properties and isotopes; explain uses and supply; relay handling information; distinguish from neighbouring rare earths.

Distinguishing features

Most reactive rare earth

Red and blue phosphor activator

Divalent and trivalent chemistry

Supply from rare earth processing

What it looks like

Silvery-white soft metal that oxidises quickly in air; compounds glow red or blue under ultraviolet light.

Physical character

atomic number: 63

melting point: about 826 degrees C

density: about 5.2 g per cubic centimetre - lowest of the lanthanides

stable isotopes: europium-151 and europium-153 isotopes - europium-151 is very weakly radioactive

How it is recognised

Element 63, lanthanide

Red and blue luminescence in phosphors

Samarium and gadolinium are neighbouring rare earths

Related models

is a kind of - the series

lanthanide

is used in - red and blue emitters

phosphor

is obtained from - monazite and bastnasite

rare earth ore

is related to - supply policy

critical raw material

In practice

Families and kinds

europium metal

europium oxide and other compounds

europium-doped phosphors

europium isotopes

europium in banknote security inks

Identifiers

chemical symbol Eu

CAS number 7440-53-1

Standards and regulation

Critical raw material lists

Chemical classification and labelling rules

Trade controls on rare earths in some countries

Failure modes and hazards

Rapid oxidation and reactivity with water

Supply disruption

Environmental impact of rare earth mining

Also called

europium-152europium-161europium-165europium-166europium-130europium-131europium-132europium-133europium-134europium-135europium-136europium-136meuropium-137europium-138europium-139europium-140europium-140meuropium-141europium-141meuropium-142europium-142meuropium-143europium-143meuropium-144europium-144meuropium-145europium-145meuropium-146europium-146meuropium-150meuropium-151meuropium-152m1europium-152m2europium-152m3europium-152m4europium-152m5europium-154m1europium-154m2europium-164europium-153

+16

Where this came from

wikidata · CC0 1.0

Also registered as vr.tr.europium

Drafted structure

Bundle to layer to finding to question, as the second pass will find it: 4 bundles · 8 layers · 8 findings · 16 questions.

Element What europium is.

Chemistry.

Properties

Properties.

Properties

Properties.

  1. What are the physical, chemical and nuclear properties of europium? definition
  2. Is the question about the element, a compound or another rare earth? boundary

Production

Ores and separation.

Production

Production.

  1. From which ores is europium obtained, and how is it separated? provenance
  2. Which entry fits rare earth processing? action
Use Applications.

Uses.

Phosphors

Phosphors and security.

Phosphors

Phosphors.

  1. How is europium used in displays, lighting and banknote security features? provenance
  2. Which entry fits phosphors? action

Other

Nuclear and medical uses.

Other

Other.

  1. How is europium used in control rods and imaging agents, in general terms? provenance
  2. Which references are standard? provenance
Safety Handling and supply.

Safety.

Handling

Handling.

Handling

Handling.

  1. What handling rules apply to europium metal and compounds? provenance
  2. Is the question about a specific workplace, which needs its safety officer? boundary

Supply

Supply.

Supply

Supply.

  1. What are production volumes, producers and criticality assessments, with sources? measurement
  2. Which sources and years are cited? provenance
Context History and research.

Context.

History

Discovery.

History

History.

  1. How was europium discovered and named? provenance
  2. Which entry fits the discoverer? action

Research

Research.

Research

Research.

  1. What research involves europium, such as luminescent probes? provenance
  2. Which entry fits luminescent materials? action

What the second pass must settle

  • Should europium phosphors be a separate entry?
  • How should supply data be linked?
  • The registry entry has merged isotope aliases; should they be split off?