gadolinium
Let an agent identify gadolinium and its properties, relay isotopes, production and uses from reference sources, describe MRI contrast agents and their safety in general terms, and distinguish gadolinium from neighbouring lanthanides.
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 identify gadolinium and its properties, relay isotopes, production and uses from reference sources, describe MRI contrast agents and their safety in general terms, and distinguish gadolinium from neighbouring lanthanides.
A chemical element with symbol Gd and atomic number 64, a silvery lanthanide with the highest thermal neutron capture cross-section of any stable element, ferromagnetic below room temperature, obtained from monazite and bastnasite and used in gadolinium-based contrast agents for magnetic resonance imaging, in neutron shielding and reactor control, in magnetic refrigeration research, in phosphors and in alloys; gadolinium has six stable isotopes plus the very long-lived gadolinium-152, with radioactive isotopes from gadolinium-134 upward.
What it is for: MRI contrast, neutron capture, magnets and phosphors.
It can be relay properties and isotopes; explain production and uses; describe contrast agent safety in general terms; distinguish from other lanthanides.
Distinguishing features
Highest neutron capture
Room-temperature Curie point
MRI contrast use
Magnetocaloric effect
What it looks like
A silvery metal that tarnishes slowly in dry air.
Physical character
atomic number: 64 Z
standard atomic weight: 157.25 u
Curie temperature: about 20 degrees C
thermal neutron cross-section: about 49000 barns - natural mixture
How it is recognised
Element 64, symbol Gd
Lanthanide of MRI contrast and neutron capture
Europium and terbium are the neighbouring lanthanides
Related models
is a kind of - in registry terms
is a kind of - in registry terms
is used in - for MRI
is adjacent to - element 65
In practice
Families and kinds
gadolinium metal and alloys
gadolinium compounds and chelates for MRI
stable isotopes from gadolinium-154 to gadolinium-160 and the long-lived gadolinium-152
radioactive isotopes such as gadolinium-134 to gadolinium-137 and gadolinium-166 and 167
gadolinium in phosphors and garnets
Identifiers
symbol Gd
CAS 7440-54-2
Standards and regulation
Drug regulation of gadolinium contrast agents, including restrictions on linear agents
Chemical safety data sheets
Nuclear material rules for neutron absorbers
Failure modes and hazards
Nephrogenic systemic fibrosis with some agents in kidney disease
Gadolinium retention and environmental release
Confusing with neighbouring lanthanides
Also called
+8
Where this came from
wikidata · CC0 1.0
Also registered as vr.tr.gadolinium
Drafted structure
Bundle to layer to finding to question, as the second pass will find it: 4 bundles · 8 layers · 8 findings · 16 questions.
Identify What gadolinium is.
Identity.
Properties
Properties.
Properties
Properties.
- What are the physical, magnetic and nuclear properties of gadolinium? definition
- Is the question about gadolinium or a neighbouring lanthanide? boundary
Isotopes
Isotopes.
Isotopes
Isotopes.
- Which isotopes exist, and which have high neutron capture? definition
- Which entry fits the specific isotope? action
Source Occurrence and production.
Supply.
Occurrence
Occurrence.
Occurrence
Occurrence.
- Where does gadolinium occur, and how is it separated? provenance
- Which entry fits rare earth mining? action
Supply
Supply.
Supply
Supply.
- Who produces gadolinium, and how is it traded, with sources? measurement
- Which sources are cited? provenance
Use Uses.
Application.
Medical
MRI contrast.
Medical
Medical.
- How do gadolinium contrast agents work, and what safety issues have regulators addressed, in general terms? provenance
- Is the user asking about their own scan, which needs a clinician? boundary
Other
Nuclear, magnetic and other uses.
Other
Other.
- How is gadolinium used in neutron shielding, magnetic refrigeration and phosphors? provenance
- Which references are standard? provenance
Context History and environment.
Context.
Discovery
Discovery.
Discovery
Discovery.
- How was gadolinium discovered by Marignac in 1880 and named after Johan Gadolin? provenance
- Which entry fits the history of the rare earths? action
Environment
Environmental gadolinium.
Environment
Environment.
- What do studies report about anthropogenic gadolinium in rivers from medical use? provenance
- Which entry fits pharmaceutical pollution? action
What the second pass must settle
- Should gadolinium contrast agent be a separate primary entry?
- How should reference and regulatory sources be linked?
- The registry entry has merged aliases naming isotopes; should they be split off?