helium encyclopedia


  • helium

    Helium (He) is a colorless, odorless, unreactive gaseous element which is the second most abundant and second lightest element in the universe (after hydrogen) has the lowest melting point and boiling point of any element. Helium is one of the noble …

  • Helium_mass_spectrometer

     · Helium mass spectrometer kg/m This article or section contains no SI units of measurement.Please help improve this article by adding international units, A helium mass spectrometer (often called a leak detector or helium leak detector) or improperly sniffer, is a scientific instrument, used to detect, locate and measure very small leaks, typically using a vacuum and injecting helium …

  • Helium

    Helium has many unique geochemical properties that make it an ideal gas for monitoring tectonic activity of deep origin: 1. Helium is extremely light and has the smallest molecular size of any gas. For this reason, it is very mobile and will readily move through a geological column (including water), propelled upward by buoyancy forces.. Helium has a cross-sectional molecular diameter one-half ...

  • Helium

    Helium He - Helium 4, R704 - UN1046 UN1963 - 7440-59-7 Materials compatibility Recommendations : Air Liquide has gathered data on the compatibility of gases with materials to assist you in evaluating which materials to use for a gas system.

  • helium | Definition, Properties, Uses, & Facts | Britannica

    Helium, chemical element, inert gas of Group 18 (noble gases) of the periodic table. The second lightest element, helium is a colorless, odorless, and tasteless gas that becomes liquid at -268.9 degrees Celsius. The boiling and freezing points of helium are lower

  • Helium

    Helium He Xenon Xe Krypton Kr Neon Ne Carbon monoxide CO n-Butane C 4 H 1 0 1-Butene C 4 H 8 2-cis-Butene C 4 H 8 2-trans-Butene C 4 H 8 Cyclopropane C 3 H 6 Deuterium D 2 Dimethylether (CH 3) 2 O Ethane C 2 H 6 Fluorine F 2 n-Heptane ...

  • Helium

    HELIUM (from Gr. ijXcos, the sun), a gaseous chemical element, the modern discovery of which followed closely on that of argon. The investigations of Lord Rayleigh and Sir William Ramsay had shown that indifference to chemical reagents did not sufficiently characterize an unknown gas as nitrogen, and it became necessary to reinvestigate other cases of the occurrence of "nitrogen" in nature.

  • Helium

    P. Rodriguez, in Encyclopedia of Materials: Science and Technology, 2001(c) Helium embrittlement Helium has a marked effect on the elevated temperature fracture behavior of metals and alloys above about 0.4 T m.The problem of helium embrittlement has come to ...

  • 헬륨

    헬륨(영어: Helium 힐리엄 [], 문화어: 헬리움 독일어: Helium 헬리움 [])은 화학 원소로, He(라틴어: Helium 헬리움 [])이고 원자번호는 2이다. 질량수가 3인 3 He과 4인 4 He이 있다.화학 원소 중 끓는점이 가장 낮으며, 상압에서는 영점에너지로 인하여 절대영도에서도 액체로 존재할 수 있는 유일한 원소다.

  • Selenium(WEB)_

    SeleniumWeb。Selenium,。IE ...

  • helium ''burning'' | Encyclopedia

     · helium ''burning'' The fusion of helium in the contracted core of a red giant star at extremely high temperatures, hotter than those reached in the Sun is particularly important because the reaction produces carbon and oxygen, so helping to explain their cosmic abundance..

  • Helium | He

    Helium is a colorless odorless gas. It is lighter than air. It is nonflammable and is only slightly soluble in water is chemically inert. When shipped as a liquid it is very cold and will solidify all other gases. Contact with the liquid will cause severe frostbite. Liquid helium is used in cryogenic research and as a nuclear reactor coolant.

  • Helium | Encyclopedia

    Helium was discovered in 1868 by Jules Janssen. Its name comes from the Greek "ἥλιος" (helios) meaning "sun". Helium is abundant in the sun''s atmosphere and is found at trace levels in Earth''s atmosphere. However, it may also be found in fossil form in

  • RP Photonics Encyclopedia

    helium–neon laser 546.074 nm green e mercury 587.5618 nm yellow d helium 589.2938 nm orange D sodium 632.8 nm red red HeNe helium–neon laser 643.8469 nm red C'' cadmium 656.2725 nm red C hydrogen 706.5188 nm red r helium 852.11 nm infrared s t

  • Keyes Helium Extraction Facility | The Encyclopedia of …

    Home | Publications| Encyclopedia | Keyes Helium Extraction Facility View A–Z Index Aerial view of the Keyes Helium Plant in 1959 (2012.201.B0255.0540, Oklahoma Publishing Company Photography Collection, OHS). Keyes Helium Extraction Facility in 1983 ...

  • Helij

    Helij (latinsko helium, angleško helium) je kemični element iz skupine žlahtnih plinov, ki ima v periodnem sistemu simbol He in atomsko število 2. Je najmanj reaktiven izmed vseh elementov, trenutno je poznanih le nekaj njegovih molekul, večina od njih je stabilna le pod visokimi pritiski. Ima najnižje tališče izmed vseh elementov pri ...

  • Ionization potential of helium

    Ionization potential of helium The principal mechanism for analyte response is ionization due to collision with metastable helium atoms.Hetastable helium atoms are generated by multiple collisions with beta electrons from the radioisotopic source.Since the ionization potential of helium (19.8 ev) is higher than that of all other species except neon, then all species entering the ionization ...

  • Helium | Article about helium by The Free Dictionary

    Helium is less dense than any other known gas except hydrogen and is about one seventh as dense as air. Extremely unreactive, it is an inert gas inert gas. any of the elements in Group 18 of the periodic table. In order of increasing atomic number they are: helium, neon, argon, krypton, xenon, and radon.

  • Helium | Encyclopedia

    Helium | Encyclopedia

  • Helium – Wikipedia

    Helium on alkuaine, joka on väritön ja hajuton jalokaasu.Se on tunnetun maailmankaikkeuden toiseksi yleisin alkuaine vedyn jälkeen, ja sitä on maailman kaikkeuden tunnetusta massasta noin neljäs osa. Sen kemiallinen merkki on He (lat. Helium) ja järjestysluku 2. ...

  • Helium – Wikipedia

    Helium on alkuaine, joka on väritön ja hajuton jalokaasu. Se on tunnetun maailmankaikkeuden toiseksi yleisin alkuaine vedyn jälkeen, ja sitä on maailman­kaikkeuden tunnetusta massasta noin neljäs­osa. Sen kemiallinen merkki on He (lat. Helium) ja järjestysluku 2. Heliumilla ei …

  • * Helium (Astronomy)

    Helium Jump to: navigation, searchThis article is about the chemical element. For other uses, see Helium (disambiguation). Helium Flash The explosive ignition of helium burning (accompanying electron degeneracy) which occurs in some giant stars. Helium was produced in the big bang and is also created in stars when hydrogen is fused into higher elements.

  • Helium

    Helium. Helium is a chemical element with symbol He and lucky number 2. It is a colorless, odorless, non-toxic, inert, monatomic gas with a tasteless sense of humor that heads the noble gas group in the periodic table. Its boiling and melting points are the lowest among the elements and it exists only as a gas, except in extreme conditions, in ...

  • Helium | John Carter Wiki | Fandom

    For information beyond the film visit Helium on Encyclopedia Barsoomia Helium is one of the main red martian kingdoms of Barsoom. It is a civilization of sophistication, technology, and intellectual pursuits. For this reason it is reffered to as "the Jewel of Barsoom." The ruler of Helium is Jeddak Tardos Mors, but it has a representative government with a senate-like body. They fly blue flags ...

  • Helium

     · It is commonly known that Helium is an element from the first period of the periodic table. But few know of the long personal, extraordinary and unique journey that she has faced over the years. Childhood [] Helium was raised by her Auntie Neutrino, along with her ...

  • How helium is made

    Helium is one of the basic chemical elements. In its natural state, helium is a colorless gas known for its low density and low chemical reactivity. It is probably best known as a non-flammable substitute for hydrogen to provide the lift in blimps and balloons.

  • Helium – Wikipedia

    Helium (altgriechisch ἥλιος hélios, deutsch ‚Sonne'') ist ein chemisches Element und hat die Ordnungszahl 2. Sein Elementsymbol ist He. Im Periodensystem steht es in der 18. IUPAC-Gruppe, der früheren VIII.Hauptgruppe, und zählt damit zu den Edelgasen.Es ...

  • Helium He - Helium 4, R704 - UN1046 UN1963 - 7440-59-7 (),()()

  • Helium, isotope of mass3 14762-55-1 wiki

    Helium, isotope of mass3 CAS 14762-55-1 WIKI information includes physical and chemical properties, USES, security data, NMR spectroscopy, computational chemical data and more. ... 1.1 Synonyms (3)2he (3)he (3he)helium 14762-55-1 3He CHEBI:30218 DB12940 Einecs 238-822-9 He 3 Helium He-3 Helium, He-3 helium, isotope of mass 3 helium-3 helium-3 atom Helium-3He, 99.8 atom % Helium …

  • Helium

    Entry for ''Helium'' - 1911 Encyclopedia Britannica - One of 8 Bible encyclopedias freely available, this resource contained over 40 million words in nearly 40,000 articles written by 1,500 respected authors

  • Helium-3

    People''s Network:。 Helium People''s Network 。 GPU Hotspot HNT, GPU 。

  • Helium

    Helium is a chemical element. It has the chemical symbol He, atomic number 2, and atomic weight of about 4.002602. There are 9 isotopes of helium, only two of which are stable. These are 3He and 4He. 4He is by far the most common isotope. Helium is called a noble gas, because it does not regularly mix with other chemicals and form new ...

  • hydrogen | Properties, Uses, & Facts | Britannica

    hydrogen (H), a colourless, odourless, tasteless, flammable gaseous substance that is the simplest member of the family of chemical elements.The hydrogen atom has a nucleus consisting of a proton bearing one unit of positive electrical charge; an electron, bearing one unit of negative electrical charge, is also associated with this nucleus.

  • ฮีเลียม

    ฮีเลียม (อังกฤษ: Helium) เป็นธาตุเคมีที่มีสัญลักษณ์ว่า He และมีเลขอะตอมเท่ากับ 2 ฮีเลียมเป็นแก๊สไม่มีสี ไม่มีกลิ่น ไม่มีรส ไม่ ...

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