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RE: Helium
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Helium shortage prompts scientist's balloon use warning

It is something guaranteed to catch the eye of most young children on a day out - a huge bunch of floating, brightly-coloured helium balloons for sale.
And for many people, a vital element in arranging a party is sitting down with a cylinder of helium to fill dozens of balloons with the lighter-than-air gas.
But according to one academic, such occasions may soon be a thing of the past.

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Helium-3
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The Helium-3 Shortage: Supply, Demand, and Options for Congress

The world is experiencing a shortage of helium-3, a rare isotope of helium with applications in homeland security, national security, medicine, industry, and science. For many years the supply of helium-3 from the nuclear weapons program outstripped the demand for helium-3. The demand was small enough that a substantial stockpile of helium-3 accumulated. After the terrorist attacks of September 11, 2001, the US federal government began deploying neutron detectors at the U.S. border to help secure the nation against smuggled nuclear and radiological material. The deployment of this equipment created new demand for helium-3. Use of the polarised helium-3 medical imaging technique also increased. As a result, the size of the stockpile shrank. After several years of demand exceeding supply, a call for large quantities of helium-3 spurred federal officials to realize that insufficient helium-3 was available to meet the likely future demand.
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Discovery of helium

In 1868 Pierre Jules CÚsar Janssen discovered how to observe solar prominences without an eclipse. While observing the solar eclipse of August 18, 1868 at Guntur, in the State of Hyderabad, British India, he noticed a bright yellow line with a wavelength of 587.49 nm in the spectrum of the chromosphere of the Sun.
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Helium clue found in echo of the big bang

The subtle signal of ancient helium has shown up for the first time in light left over from the big bang. The discovery will help astronomers work out how much of the stuff was made during the big bang and how much was made later by stars.
Helium is the second-most abundant element in the universe after hydrogen. The light emitted by old stars and clumps of hot pristine gas from the early universe suggest helium made up some 25 per cent of the ordinary matter created during the big bang.

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When scientists in France and England discovered helium 140 years ago, their eyes were on the sun, not on Texas. Yet decades later, the Lone Star State became the epicenter of the "lifting gas," and Amarillo gained the title "Helium Capital of the World." Still today, the federal helium facility northwest of Amarillo accounts for a third of the world's supply of helium.
The European astronomers first identified helium when they were studying a solar eclipse and spotted a previously undetected yellow atmospheric band around the sun. Another 27 years would pass before scientists discovered helium in minerals on Earth.

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The A-B phase boundary in superfluid 3He
The A-B transition is an exemplar first-order phase boundary. To date, we have measured the latent heat, surface tension, inter-phase contact angle at cell walls, and heterogeneous nucleation phenomena. Most recently, we have made a magnetic 'trap' so that the transition from the B to A phase can be induced away from the container wall, free from the influence of any impurities or defects. These will be the first ever measurements of such pure homogeneous nucleation.

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A "universe in a test tube" that could be used to assess theories of everything has been created by physicists.
The test tube, the size of a little finger, has been cooled to a fraction of a degree above the lowest possible temperature, absolute zero, which is just over 273 degrees below the freezing point of water.
Inside the tube an isotope of helium (called helium three) forms a "superfluid", an ordered liquid where all the atoms are in the same state according to the theory that rules the subatomic domain, called quantum theory.
What is remarkable is that atoms in the liquid, at temperatures within a thousandth of a degree of absolute zero, form structures that, according to the team at Lancaster University, are similar those seen in the cosmos.

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Helium-8
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The Size of the Helium-8 Nucleus Has Been Measured
To be more precise, the charge radius of this heaviest of helium isotopes (containing two protons and six neutrons) has been measured for the first time. The charge radius tells you how widely the proton charge is spread out in space. The new work, conducted by a Argonne-Chicago-GANIL-Windsor (Canada)-Los Alamos collaboration, arrives at a value of 1.93 fm (1 fermi equals 10^-15 m). For comparison, the charge radius of the He-6 isotope, is 2.068 fm; that is, the lighter isotope actually has a larger charge radius, the result of the binding effect of the strong nuclear force. He-8 is very rare, hard to make, and represents the most neutron-rich material known on Earth. Still heavier helium groupings, such as He-10, are not really bound entities-they can only be considered as resonances.

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Helium
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Helium is the talk of the party balloon industry these days, and it is not a discussion being carried out in high-pitched giggles.
The second most plentiful element in the universe is suddenly in short supply on this planet, and that means soaring prices for a lot of things, balloons included.

"Have you heard the one about the chemist who was reading a book about helium and just couldn't put it down?"

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Helium (He) is a colourless, odourless, tasteless, non-toxic, inert monatomic chemical element that heads the noble gas series in the periodic table and whose atomic number is 2. Its boiling and melting points are the lowest among the elements and it exists only as a gas except in extreme conditions.

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