• nuclei
  • Most terrestrial helium present today is created by the natural radioactive decay of heavy radioactive elements ( thorium and uranium , although there are other examples), as the alpha particles emitted by such decays consist of helium-4 nuclei . (wikipedia.org)
  • It explains the fact that, in the first few minutes after the Big Bang, as the "soup" of free protons and neutrons which had initially been created in about a 6:1 ratio cooled to the point where nuclear binding was possible, almost all atomic nuclei to form were helium-4 nuclei. (wikipedia.org)
  • found helium
  • The formal discovery of the element was made in 1895 by two Swedish chemists, Per Teodor Cleve and Nils Abraham Langlet , who found helium emanating from the uranium ore cleveite . (wikipedia.org)
  • Researchers from the University of Oxford found helium released from rocks by underlying volcanic heat, and they found a lot of it. (wired.com)
  • Helium's
  • The combination of helium's extremely low molecular weight and weak interatomic reactions yield interesting properties when helium is cooled below its critical temperature of 5.2 K to form a liquid. (wikipedia.org)
  • When helium's price goes up-like it has for most of the past few years-natural gas companies are incentivized to sell extracted helium on its own. (wired.com)
  • inert
  • But worldwide, helium is about a thousand times less lucrative than gas, so even though removing (inert) helium makes the gas burn better, companies don't usually bother to take it out. (wired.com)
  • nucleus
  • In a similar way, the particular energetic stability of the helium-4 nucleus, produced by similar effects, accounts for the ease of helium-4 production in atomic reactions involving both heavy-particle emission and fusion. (wikipedia.org)
  • The unusual stability of the helium-4 nucleus is also important cosmologically. (wikipedia.org)
  • The antiproton's orbit, which has a large principal quantum number and angular momentum quantum number of around 38, lies far away from the surface of the helium nucleus. (wikipedia.org)
  • An antiprotonic helium ion is a two-body object composed of a helium nucleus and orbiting antiproton. (wikipedia.org)
  • Liquid
  • Liquid helium is used in cryogenics (its largest single use, absorbing about a quarter of production), particularly in the cooling of superconducting magnets , with the main commercial application being in MRI scanners. (wikipedia.org)
  • Within this liquid state, helium has two phases referred to as helium I and helium II. (wikipedia.org)
  • From observations, liquid helium only exhibits super-fluidity because it contains isolated islands of BECs, which have well-defined magnitude and phase, as well as well-defined phonon-roton (P-R) modes. (wikipedia.org)
  • Liquid helium is used as a coolant for various superconducting applications. (wikipedia.org)
  • Another beneficial aspect of the liquid helium quantum system is that application of an electrical potential to liquid helium in a vacuum can move qubits with little decoherence. (wikipedia.org)
  • In other words, voltage can manipulate qubits with little effect on the ordering of the phase angles in the wave functions between the components of the liquid helium quantum system. (wikipedia.org)
  • white dwarf
  • A helium-rich planetary object may also form from a low-mass white dwarf, which gets depleted of hydrogen via mass transfer in a close binary system with a second, massive object like e.g. a neutron star. (wikipedia.org)
  • One scenario involves an AM CVn type of symbiotic binary star composed of two helium-core white dwarfs surrounded by a circumbinary helium accretion disk formed during mass transfer from the less massive to the more massive white dwarf. (wikipedia.org)
  • A much rarer runaway helium fusion process can also occur on the surface of accreting white dwarf stars. (wikipedia.org)
  • The degenerate helium core will keep on contracting, and finally becomes a helium white dwarf. (wikipedia.org)
  • dimer
  • The dimer then explodes as two helium cations ions repel each other with the same speed but opposite directions. (wikipedia.org)
  • The helium dimer can be formed in small amounts when helium gas expands and cools as it passes through a nozzle in a gas beam. (wikipedia.org)
  • The helium dication dimer He22+ is extremely repulsive and would release much energy when it dissociated, around 835 kJ/mol. (wikipedia.org)
  • The helium trimer is large, being more than 100 Å, which is even larger than the helium dimer. (wikipedia.org)
  • interatomic
  • In this state, the zero point vibrational energies of helium are comparable to very weak interatomic binding interactions, thus preventing lattice formation and giving helium its fluid characteristics. (wikipedia.org)
  • nitrogen
  • Clathrates are also possible with helium under pressure in ice, and other small molecules such as nitrogen. (wikipedia.org)
  • The substance is made by compressing nitrogen and helium in a diamond anvil cell. (wikipedia.org)
  • In Technical diving where breathing gas mixtures known as Trimix comprising oxygen, helium and nitrogen are used, it is necessary to know the fraction of helium in the mixture to reliably calculate decompression schedules for dives using that mixture. (wikipedia.org)
  • The thermal conductivity of nitrogen and oxygen are very similar, and that of helium very different so that the ratio of oxygen and nitrogen in the mix is relatively unimportant, and need not be compensated. (wikipedia.org)
  • He's breathing air in which nitrogen- the gas which can give people the bends- has been replaced by helium. (npr.org)
  • enables
  • Dashboard enables users to view their entire Helium deployment and administer all hardware, software, and organizational components. (helium.com)
  • The Helium AWS IoT Channel enables you to quickly send Helium device data to AWS IoT with little effort, while adhering to their schema and security best practices. (helium.com)
  • radioactive decay
  • However, recent studies suggest that helium produced deep in the earth by radioactive decay can collect in natural gas reserves in larger than expected quantities, in some cases having been released by volcanic activity. (wikipedia.org)
  • Radioactive decay from other elements is the source of most of the helium-4 found on Earth, produced after the planet cooled and solidified. (wikipedia.org)
  • While some helium is made naturally through radioactive decay, it's not a huge amount and it's generally spread out over the crust. (wired.com)
  • relatively
  • A relatively new dating method, tritium-helium dating has been developed for determining rates of oxygen utilization in the ocean. (wikipedia.org)
  • A good source will be about 3 percent helium, but more often helium hovers between 0.1 percent and 0.5 percent-nothing compared to the relatively astronomical 10 percent pocket found in Tanzania. (wired.com)
  • Countries like Qatar mine so much natural gas that even though it has relatively little helium, they can crank out a decent percentage of the world's demand as an afterthought. (wired.com)
  • consist
  • This is in contrast to ordinary gas giants such as Jupiter and Saturn, whose atmospheres consist primarily of hydrogen, with helium as a secondary component only. (wikipedia.org)
  • citation needed
  • Helium planets are predicted to have roughly the same diameter as hydrogen-helium planets of the same mass.[citation needed] A scenario for forming helium planets from regular giant planets involves an ice giant, in an orbit so close to its host star that the hydrogen effectively boils out of the atmosphere, evaporating from and escaping the gravitational hold of the planet. (wikipedia.org)
  • Previously
  • Previously, terrestrial helium-a non-renewable resource, because once released into the atmosphere it readily escapes into space-was thought to be in increasingly short supply. (wikipedia.org)
  • Previously, a helium star was a synonym for a B class star, but this usage is considered obsolete. (wikipedia.org)
  • oxygen
  • However for greater accuracy and compensation to oxygen cross-sensitivity, some instruments include an oxygen cell, and in these cases can generally give a full helium and oxygen analysis of the mixture simultaneously. (wikipedia.org)
  • http://www.geo.arizona.edu/~reiners/arhdl/longer.htm U-Th/He dating, the University of Arizona Geochronology Lab http://www.sciencemag.org/cgi/content/abstract/sci;196/4287/291 W. J. Jenkins, Tritium-Helium Dating in the Sargasso Sea: A Measurement of Oxygen Utilization Rates, Science 15 April 1977: Vol. 196. (wikipedia.org)
  • gases
  • The star will drive off lighter gases more effectively through evaporation than heavier gasses, and over time deplete the hydrogen, leaving a greater proportion of helium behind. (wikipedia.org)
  • The planet's atmosphere will experience a large energy input and because light gases are more readily evaporated than heavier gases, the proportion of helium will steadily increase in the remaining atmosphere. (wikipedia.org)
  • Instrument to measure the concentration of helium in a gas mixture A Helium analyzer is an instrument used to identify the presence and concentration of helium in a mixture of gases. (wikipedia.org)
  • molecules
  • Helium trimer molecules have been produced by expanding cold helium gas from a nozzle into a vacuum chamber. (wikipedia.org)
  • The kind of grating used needs to have empty space between the bars, so that molecules can pass through, glass would stop helium. (wikipedia.org)
  • tanks
  • Most of the remainder currently comes from the Federal Helium Program's underground tanks in Amarillo, Texas-though that's changing. (wired.com)
  • People can rent helium gas tanks for use at parties, but they must follow safety guidelines for transport and use. (ehow.co.uk)
  • Turn off the car engine before loading or unloading helium tanks. (ehow.co.uk)
  • Strap helium tanks to a wheeled cart or dolly to move them. (ehow.co.uk)
  • Never drag or roll helium tanks. (ehow.co.uk)
  • Always keep helium tanks upright, supervised and away from children. (ehow.co.uk)
  • Always ensure proper ventilation when driving with or moving helium tanks, since the inhalation of helium gas can cause asphyxiation. (ehow.co.uk)
  • phases
  • In scientific research, the behavior of the two fluid phases of helium-4 (helium I and helium II) is important to researchers studying quantum mechanics (in particular the property of superfluidity ) and to those looking at the phenomena, such as superconductivity , produced in matter near absolute zero . (wikipedia.org)
  • element
  • This is possible because all data on the Helium network is encrypted so we can guarantee that only you have access to it regardless of which Element is responsible for it at the local level. (helium.com)
  • All data that is routed through a Helium Element Access Point is encrypted and never inspected by the Access Point itself. (helium.com)
  • Helium is the most unreactive element, so it was commonly believed that helium compounds do not exist at all. (wikipedia.org)
  • Helium is a chemical element with symbol He and atomic number 2. (wikipedia.org)
  • ionization energy
  • However, numerical approximations of the equations of quantum mechanics have given a good estimate of the key atomic properties of helium-4, such as its size and ionization energy. (wikipedia.org)
  • quantum mechanical
  • As the hydrogen in the core is exhausted, some of the helium left behind is instead compacted into degenerate matter, supported against gravitational collapse by quantum mechanical pressure rather than thermal pressure. (wikipedia.org)
  • rapidly
  • Once the temperature reaches 100 million-200 million kelvin and helium fusion begins using the triple-alpha process, the temperature rapidly increases, further raising the helium fusion rate and, because degenerate matter is a good conductor of heat, widening the reaction region. (wikipedia.org)
  • planets
  • Suitable pressures to force helium into solid combinations could be found inside planets. (wikipedia.org)
  • Helium planets are expected to be distinguishable from regular hydrogen-dominated planets by strong evidence of carbon monoxide and carbon dioxide in the atmosphere. (wikipedia.org)
  • Due to the atmospheric composition, helium planets are expected to be white or grey in appearance. (wikipedia.org)
  • sensors
  • Gas blending#Gas analysis Thermal Conductivity Sensors ANALOX 8000 - Helium Analyse User Manual, Analox Sensor Technology Ltd, 15 Ellerbeck Court, Stokesley Business Park, North Yorkshire, TS9 5PT, "Archived copy" (PDF). (wikipedia.org)