Hf (Noun)
Meaning 1
A grey tetravalent metallic element that resembles zirconium chemically and is found in zirconium minerals; used in filaments for its ready emission of electrons.
Classification
Nouns denoting substances.
Examples
- Hafnium is a grey tetravalent metallic element that resembles zirconium chemically and is found in zirconium minerals.
- The periodic table shows that hafnium has the atomic number 72.
- Hf is used in filaments for its ready emission of electrons.
- Scientists discovered the element hafnium in 1923 while studying zirconium minerals.
- Atomic number 72 corresponds to the symbol Hf on the periodic table.
Synonyms
Hypernyms
Meaning 2
3 to 30 megahertz.
Classification
Nouns denoting attributes of people and objects.
Examples
- The amateur radio operator adjusted her transmitter to operate on the hf band, allowing her to communicate with other operators around the world.
- The hf antenna was carefully tuned to resonate at 14.2 megahertz, a popular frequency for international communication.
- The radio spectrum allocation chart showed that the hf band spanned from 3 to 30 megahertz, with various sub-bands allocated for different uses.
- The hf propagation conditions were favorable, allowing the signal to bounce off the ionosphere and reach distant receivers.
- The hf transceiver was a complex device that required careful setup and tuning to operate effectively on the desired frequency.