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
Nikolai Kasterin Since 1930 he was a consultant for various scientific institutions including CAGI, Angarsrtoy and the National Institute of Building Materials. Kasterin authored more than forty scientific publications in theoretical physics. He was also known for his works opposing special relativity. Nikolai Kasterin Nikolai Petrovich Kasterin (1869–1947) was a Russian physicist, student of Aleksandr Stoletov. His 1903 doctoral dissertation, portions of which were published in German in the Proceedings of the Royal Academy of Sciences in Amsterdam under the sponsorship of Heike Kamerlingh Onnes, is considered to be a pivotal contribution to multiple scattering theory (MST) by such experts as Paul