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Showing 1 to 4 of 4 for “"thermal vacancies"”.
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Thermal vacancies in solid helium-3
Thermal vacancy concentrations in crystals of 3He have been determined from high precision measurements of the tem3 perature dependence of the x-ray lattice parameter. Bcc He 3 was studied for molar volumes ranging from 20.3 to 24.8 cm ; mole for which the melting temperatures range from 2.36 to …
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Thermal vacancies in HCP helium-4
Activation energies of thermal vacancies have been determined in hcp $\sp4$He as a function of molar volume. A sensitive strain gauge was used to measure the temperature dependence of the pressure in twenty crystals between 18.17 and 20.9 cm$\sp3$/mole. Absolute lattice parameters at low …
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Thermal vacancies in hcp helium-4
Activation energies of thermal vacancies have been determined in hcp 4He as a function of molar volume. A sensitive strain gauge was used to measure the temperature dependence of the pressure in twenty crystals between 18.17 and 20.9 cm3/mole. Absolute lattice parameters at low temperatures were …
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Thermal vacancies and phase separation in bcc mixtures of helium-3 and helium-4
Thermal vacancy concentrations in crystals of 3He-4He mixtures have been determined from accurate measurements of the temperature dependence of the x-ray lattice parameter. A new x-ray diffractometer-position sensitive detector system is used to make measurements of the absolute lattice parameter …