Search results
Results from the WOW.Com Content Network
The pharmaceutical industry is reliant on helium. And so is the Department of Defense.” ... shot down by the U.S. military on Saturday after passing over the northern U.S. earlier in the week ...
A global helium shortage has doctors worried about one of the natural gas’s most essential, and perhaps unexpected, uses: MRIs.. Strange as it sounds, the lighter-than-air element that gives ...
Liquid helium is a physical state of helium at very low temperatures at standard atmospheric pressures.Liquid helium may show superfluidity.. At standard pressure, the chemical element helium exists in a liquid form only at the extremely low temperature of −269 °C (−452.20 °F; 4.15 K).
Helium also has a very low boiling point (-268.9°C or -452°F), allowing it to remain a gas even in super-cold environments, an important feature because many rocket fuels are stored in that ...
Each atom of helium-4 is a boson particle, by virtue of its integer spin. A helium-3 atom is a fermion particle; it can form bosons only by pairing with another particle like itself, which occurs at much lower temperatures. The discovery of superfluidity in helium-3 was the basis for the award of the 1996 Nobel Prize in Physics. [1]
A major advantage is that this gas is noncombustible. But the use of helium has some disadvantages, too: The diffusion issue shared with hydrogen (though, as helium's molecular radius (138 pm) is smaller, it diffuses through more materials than hydrogen [4]). Helium is expensive. Although abundant in the universe, helium is very scarce on Earth.
Helium usually makes up a minuscule portion of natural gas, but can make up as much as 10 percent of natural gas in some fields. A helium content of 0.3 percent or more is considered necessary for commercial helium extraction. [1] In 2012, helium was recovered at 16 extraction plants, from gas wells in Colorado, Kansas, Oklahoma, Texas, and ...
Terrestrial helium consists almost exclusively (all but ~2ppm) [16] of 4 He. 4 He's boiling point of 4.2 K is the lowest of all known substances except 3 He. When cooled further to 2.17 K, it becomes a unique superfluid with zero viscosity. It solidifies only at pressures above 25 atmospheres, where it melts at 0.95 K.