CPC Definition - Subclass G21G

Last Updated Version: 2016.11
CONVERSION OF CHEMICAL ELEMENTS; RADIOACTIVE SOURCES (applications of radiation in general G21H 5/00; handling particles, e.g. neutrons, or electromagnetic radiation not otherwise provided for G21K)
Definition statement

This place covers:

Methods and apparatus for the conversion of chemical elements, e.g. isotope production or transmutation where a change of atomic number takes place either externally induced or by radioactive decay.

Radioactive sources (solid, liquid or gas).

References
Limiting references

This place does not cover:

Conversion of nuclear fuel

G21C

Adaptations of reactors to facilitate experimentation or irradiation. Examples of such adaptations include modification of the reactor core to enable exposure of samples for investigative purposes

G21C 23/00

Applications of radiation in general

G21H 5/00

Handling particles.

G21K

Irradiation devices. These typically include arrangements to deliberately subject bodies or materials to ionising radiation in order to take advantage of known effects of the radiation thereon

G21K 5/00

X-ray tubes

H01J 35/00

Application-oriented references

Examples of places where the subject matter of this place is covered when specially adapted, used for a particular purpose, or incorporated in a larger system:

Radiopharmaceuticals

A61K 51/00

Applying radioactive material to the body

A61M36/00

Radiation therapy using radioactive sources

A61N 5/10

Detection by neutron activation

G01N 23/222

Conversion of chemical elements by thermonuclear reactions in fusion reactors

G21B

Nuclear reactors

G21C

Application of radiation from radioactive sources

G21H 5/00

Informative references

Attention is drawn to the following places, which may be of interest for search:

Preparations containing radioactive substances for use in therapy or testing in vivo

A61K 51/00

Separation of different isotopes of the same element

B01D 59/00

In fusion reactors

G21B

In nuclear reactors

G21C

By cosmic radiation

G21H 7/00

Handling particles or electro​magnetic radiation not otherwise provided for

G21K

X-ray tubes

H01J 35/00

Gamma masers

H01S 4/00

In accelerators

H05H

Producing neutrons or other subatomic particles, X- or gamma rays:

Special rules of classification

Indexing Codes are only used for G21G 1/00, G21G 1/0005 and G21G 1/001 for indicating supplementary information. In all other cases multiple ECLA classes are assigned.

Arrangements for converting chemical elements by electromagnetic radiation, corpuscular radiation or particle bombardment, e.g. producing radioactive isotopes (separation of different isotopes of the same element B01D 59/00)
Definition statement

This place covers:

  • Apparatus and methods for transmutation and isotope production.
  • Conversion isotope generators methods of isotope recovery from targets.
  • Arrangements inside nuclear power reactors
  • Arrangements outside nuclear power reactors, e.g. conversion by bombardment with electrically charged particles or neutrons.

Further information:

The indexing scheme under G21G 1/00 covers: isotope delivery systems; methods for recovering isotopes. Individual subgroups are used to identify particular isotopes recovered from irradiated targets.

References
Limiting references

This place does not cover:

Separation of different isotopes of the same element (enrichment)

B01D 59/00

Informative references

Attention is drawn to the following places, which may be of interest for search:

Applications of electromagnetic radiation

G21H 5/00

Irradiation devices

G21K 5/00

Targets for nuclear reactions

H05H 6/00

Special rules of classification

Referring to reactors is intended for power reactors which primarily supply electricity to the power grid; otherwise G21G 1/06 should be used.

May be assigned to inventions in other classes where isotope conversion, recovery or delivery takes place but is not the main focus.

G21G 2001/0015 through G21G 2001/0094 should only be used these particular isotopes are recovered. For more general methods, useful for large groups/lists of isotopes, G21G 1/001 should be given.

Glossary of terms

In this place, the following terms or expressions are used with the meaning indicated:

Transmutation

Conversion of nuclear waste to less problematic isotopes.

Generator

Shielded delivery system containing a mother isotope which can be eluted or "milked" to deliver an isotope product, which usually has a short half-life, e.g. Technetium-99m.

Synonyms and Keywords

In patent documents, the following abbreviations are often used:

Isotope delivery system

"Generator", "cow", ion exchange column.

Radioactive sources (producing neutrons or other subatomic particles, X- or gamma rays, in fusion reactors G21B, in nuclear reactors G21C, by cosmic radiation G21H 7/00, in accelerators H05H; X-ray tubes H01J 35/00; gamma masers H01S 4/00)
Definition statement

This place covers:

  • Sources of ionising radiation which emit according to radioactive decay.
  • Neutron sources or other sources used generally or for medical applications.
References
Limiting references

This place does not cover:

Producing neutrons or other subatomic particles, X- or gamma rays in fusion reactors

G21B

Producing neutrons or other subatomic particles, X- or gamma rays in nuclear reactors

G21C

Producing neutrons or other subatomic particles, X- or gamma rays by cosmic radiation

G21H 7/00

Informative references

Attention is drawn to the following places, which may be of interest for search:

Radioactive dressings

A61M36/14

Radiation therapy

A61N 5/00

Filling medical containers

B65B 3/003

Filling medical containers and related operations

B65B 3/006

Producing neutrons or other subatomic particles, X- or gamma rays by using sources as tracers

G21H 5/02

X-ray tubes

H01J 35/00

Gamma masers

H01S 4/00

Plasma eUV sources

H05G 2/00

Production of accelerated electrically-charged particles or of neutrons, e.g. using accelerators

H05H

Alleged conversion of chemical elements by chemical reaction
Definition statement

This place covers:

Alchemy, e.g. alleged induction of radioactive decay by chemical means.

References
Limiting references

This place does not cover:

Cold fusion

G21B 3/00

Special rules of classification

This main group should only be given when a change of atomic number by chemical means is explicitly disclosed. This may also include alleged induction of radioactive decay by chemical means.

Conversion of chemical elements not provided for in other groups of this subclass
Definition statement

This place covers:

Miscellaneous apparatus or methods for converting elements or generating isotopes not induced by electromagnetic radiation, corpuscular radiation or particle bombardment.

Such methods which contradict standard physics.

Special rules of classification

This main group should only be given if no other group in this subclass can be assigned.