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
History of thermodynamics years later by Heike Kamerlingh Onnes, who based it on the Greek word "enthalpein" meaning "to warm". Building on these foundations, those as Lars Onsager, Erwin Schrödinger, and Ilya Prigogine, and others, functioned to bring these engine "concepts" into the thoroughfare of almost every modern-day branch of science. The idea that heat is a form of motion is perhaps an ancient one and is certainly discussed by Francis Bacon in 1620 in his "Novum Organum". The first written scientific reflection on the microscopic nature of heat is probably to be found in a work by Mikhail Lomonosov, in which he