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Nature Chemistry, 2012
Owing to peculiar properties, helium has taken both the main and supporting roles in scientific discoveries over the years. Christine Herman explores just what makes it such a cool element.
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Owing to peculiar properties, helium has taken both the main and supporting roles in scientific discoveries over the years. Christine Herman explores just what makes it such a cool element.
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Science, 1979
Helium appears indispensable for certain energy-related uses that may be important 50 years from now, when helium-bearing natural gas, a much cheaper source than air, may be exhausted. Present demand, however, is lower than productive capacity, and much helium is being dissipated into the atmosphere as natural gas is burned for fuel.
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Helium appears indispensable for certain energy-related uses that may be important 50 years from now, when helium-bearing natural gas, a much cheaper source than air, may be exhausted. Present demand, however, is lower than productive capacity, and much helium is being dissipated into the atmosphere as natural gas is burned for fuel.
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Electron capture into excited states of helium by helium-ion impact on helium
Physical Review A, 1975Cross sections for electron capture into each excited state of He up to 4 $sup 1$,$sup 3$D by He$sup +$ impact on He in the energy range 100--10 000 keV have been calculated by means of the first Born approximation (Bates's version). A Gaussian technique previously developed for evaluating two-center integrals occurring in the Born amplitude has been ...
Thomas G. Winter, Chun C. Lin
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Physical Review, 1946
A helium cryostat which is cooled by the isentropic expansion of helium without the aid of liquid air or other refrigerant provides a cold chamber for experiments at any temperature down to 2°K. Any gas can be liquefied and delivered to external receivers as desired. Three expansion devices are described. One is a diaphragm engine having a mechanically
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A helium cryostat which is cooled by the isentropic expansion of helium without the aid of liquid air or other refrigerant provides a cold chamber for experiments at any temperature down to 2°K. Any gas can be liquefied and delivered to external receivers as desired. Three expansion devices are described. One is a diaphragm engine having a mechanically
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ACM SIGGRAPH 2005 Electronic Art and Animation Catalog, 2005
Adam Janeczek +2 more
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Adam Janeczek +2 more
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Scattering of helium atoms by liquid helium
Physical Review B, 1986, Goodman, , Garcia
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Molybdenum‐helium and helium‐helium interaction potentials from helium desorption experiments
physica status solidi (b), 1978W. F. W. M. van Heugten +2 more
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Helium separation using membrane technology: Recent advances and perspectives
Separation and Purification Technology, 2021Zhongde Dai, Jing Deng, Xuezhong He
exaly
NONLOCALITY IN (HELIUM-HELIUM) INTERATOMIC POTENTIALS
1976Publisher Summary This chapter highlights the nonlocality in interactomic potentials. Interatomic potentials are usually taken to be purely local. With this assumption, the potential is obtained through the use of Born–Oppenheimer approximation. This usually leads to a long range attractive van der Waals' potential and a short range steep repulsion ...
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The ionisation of helium by neutral helium atoms
1944A method is described for investigating the ionisation produced in helium by collisions between quasi-stationary atoms of helium - that is, atoms possessing only thermal velocities - and a beam of neutral helium atoms with kinetic energy less than one hundred electron volts. Ionisation is shown to begin when the kinetic energy of the impinging particle
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