Liquid helium of liquid water. Helium was first liquefied on July 10, 1908, by the Dutch physicist Heike Kamerlingh Onnes at the University of Leiden in the Netherlands. At that time, helium-3 was unknown because the mass spectrometer had not yet been invented. In more recent decades, liquid helium has been used as a cryogenic refrigerant, and liquid helium is produced commercially for use in superconducting magnets such as those used in magnetic resonance imaging (MRI), nuclear magnetic resonance (NMR), Magnetoencephalography (MEG), and experiments in physics, such as low temperature Mössbauer spectroscopy. The temperature required to produce liquid helium is low because
Harm Kamerlingh Onnes Harm Kamerlingh Onnes Harm Henrick Kamerlingh Onnes (15 February 1893 – 20 May 1985 in Leiden) was a Dutch portrait painter and ceramist, who also produced designs for stamps and stained-glass windows. He is best known for the small, humorous vignettes of everyday life. Kamerlingh Onnes was born in Zoeterwoude in 1893. His father Menso Kamerlingh Onnes was a painter and member of the Hague School, who in 1911 gave his son permission to develop as an artist. He also gave him his first drawing and painting lessons. One of his uncles was the painter Floris Verster, and another uncle