Helium-3 Shortage Could Put Freeze On Low-Temperature Research

Science ◽  
2009 ◽  
Vol 326 (5954) ◽  
pp. 778-779 ◽  
Author(s):  
A. Cho
Keyword(s):  
Low Temperature ◽  
Helium 3

scholarly journals Phase Transitions and Topological Defects in the Early Universe

1997 ◽  
Vol 50 (4) ◽  
pp. 697 ◽  
Author(s):  
T. W. B. Kibble
Keyword(s):  
Phase Transitions ◽  
Low Temperature ◽  
Early Universe ◽  
Particle Physics ◽  
Defect Density ◽  
Cosmic Strings ◽  
Condensed Matter ◽  
Topological Defects ◽  
Helium 3 ◽  
The Universe

Our present theories of particle physics and cosmology, taken together, suggest that very early in its history, the universe underwent a series of phase transitions, at which topological defects, similar to those formed in some condensed matter transitions, may have been created. Such defects, in particular cosmic strings, may survive long enough to have important observable effects in the universe today. Predicting these effects requires us to estimate the initial defect density and the way that defects subsequently evolve. Very similar problems arise in condensed matter systems, and recently it has been possible to test some of our ideas about the formation of defects using experiments with liquid helium-3 (in collaboration with the Low Temperature Laboratory in Helsinki). I shall review the present status of this theory.

Low-temperature polarized helium-3 for MRI applications

1999 ◽  
Vol 41 (6) ◽  
pp. 1084-1087 ◽  
Author(s):  
Frank Kober ◽  
Pierre-�tienne Wolf ◽  
Jean-Louis Leviel ◽  
G�rard Vermeulen ◽  
Guillaume Duhamel ◽  
...  
Keyword(s):  
Low Temperature ◽  
Helium 3 ◽  
Polarized Helium

scholarly journals Rat lung MRI using low-temperature prepolarized helium-3

2001 ◽  
Vol 45 (6) ◽  
pp. 1130-1133 ◽  
Author(s):  
Frank Kober ◽  
Pierre-Etienne Wolf ◽  
Gérard Vermeulen ◽  
Guillaume Duhamel ◽  
Laurent Lamalle ◽  
...  
Keyword(s):  
Low Temperature ◽  
Rat Lung ◽  
Helium 3 ◽  
Lung Mri

Exsolution and inversion in pigeonite from the Whin Sill, Northern England

1978 ◽  
Vol 36 (1) ◽  
pp. 474-475
Author(s):  
P.P.K. Smith
Keyword(s):  
High Temperature ◽  
Low Temperature ◽  
Homogeneous Nucleation ◽  
Silicate Mineral ◽  
Antiphase Boundaries ◽  
Two Phase ◽  
Primitive Form ◽  
The Core ◽  
Nucleation Mechanisms ◽  
And Inversion

Grains of pigeonite, a calcium-poor silicate mineral of the pyroxene group, from the Whin Sill dolerite have been ion-thinned and examined by TEM. The pigeonite is strongly zoned chemically from the composition Wo8En64FS28 in the core to Wo13En34FS53 at the rim. Two phase transformations have occurred during the cooling of this pigeonite:- exsolution of augite, a more calcic pyroxene, and inversion of the pigeonite from the high- temperature C face-centred form to the low-temperature primitive form, with the formation of antiphase boundaries (APB's). Different sequences of these exsolution and inversion reactions, together with different nucleation mechanisms of the augite, have created three distinct microstructures depending on the position in the grain.In the core of the grains small platelets of augite about 0.02μm thick have farmed parallel to the (001) plane (Fig. 1). These are thought to have exsolved by homogeneous nucleation. Subsequently the inversion of the pigeonite has led to the creation of APB's.

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