Gigantic asymmetry of phase separation and homogenization kinetics in solid 3He–4He mixtures

The pressure dependence (3.01 MPa ≤ P ≤ 4.28 MPa) of the phase-separation temperature of solid mixtures of 3He and 4He has been measured for 3He concentrations of 0.20 and 0.30 using X-ray diffraction. The value determined for the pressure dependence of the critical temperature is compared with the prediction by Mullin and with other experiments.

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Homogeneous nucleation in phase separation of solid 3He–4He mixtures

Physica B Condensed Matter ◽

10.1016/s0921-4526(02)01948-8 ◽

2003 ◽

Vol 329-333 ◽

pp. 189-190

Author(s):

M. Poole ◽

A. Smith ◽

V.A. Maidanov ◽

E.Ya. Rudavskii ◽

V.N. Grigor'ev ◽

...

Keyword(s):

Phase Separation ◽

Homogeneous Nucleation ◽

Solid 3He

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Sans Study of Phase Separation in Solid 3He-4He

MRS Proceedings ◽

10.1557/proc-376-335 ◽

1994 ◽

Vol 376 ◽

Cited By ~ 1

Author(s):

J.P. Koster ◽

S.E. Nagler ◽

E.D. Adams ◽

G.D. Wignall

Keyword(s):

Phase Separation ◽

Neutron Scattering ◽

Small Angle ◽

Late Stage ◽

Small Angle Neutron Scattering ◽

Study Phase ◽

Simple Interpretation ◽

Phase Separation Kinetics ◽

Separation Kinetics ◽

Solid 3He

ABSTRACTSmall angle neutron scattering has been used to study phase separation in a quantum alloy, solid 3Hex-4He1-x. The onset of phase separation is marked by a dramatic increase in the measured scattering. A simple interpretation of the results suggests that the late-stage phase separation kinetics are dominated by an increase in the concentration of 3He atoms in preexisting precipitate regions.

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Bulk standards for low-temperature biological x-ray microanalysis

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100111525 ◽

1984 ◽

Vol 42 ◽

pp. 282-283

Author(s):

P. Echlin ◽

M. McKoon ◽

E.S. Taylor ◽

C.E. Thomas ◽

K.L. Maloney ◽

...

Keyword(s):

Phase Separation ◽

Low Temperature ◽

Analytical Method ◽

Salt Solutions ◽

Absolute Concentration ◽

Cooling Process ◽

X Ray ◽

The Absolute ◽

Analytical Procedures ◽

Electrical Conductors

Although sections of frozen salt solutions have been used as standards for x-ray microanalysis, such solutions are less useful when analysed in the bulk form. They are poor thermal and electrical conductors and severe phase separation occurs during the cooling process. Following a suggestion by Whitecross et al we have made up a series of salt solutions containing a small amount of graphite to improve the sample conductivity. In addition, we have incorporated a polymer to ensure the formation of microcrystalline ice and a consequent homogenity of salt dispersion within the frozen matrix. The mixtures have been used to standardize the analytical procedures applied to frozen hydrated bulk specimens based on the peak/background analytical method and to measure the absolute concentration of elements in developing roots.

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Phase separation in sol gel-derived ceramic films of silica-zirconia, alumina-zirconia, and titania-zirconia system

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100170967 ◽

1994 ◽

Vol 52 ◽

pp. 646-647

Author(s):

J. Tong ◽

L. Eyring

Keyword(s):

Fracture Toughness ◽

Phase Separation ◽

Sol Gel ◽

Great Influence ◽

High Strength ◽

Chemical Durability ◽

Separation Method ◽

Toughening Mechanism ◽

Ceramic Films ◽

Zirconia Toughened Alumina

There is increasing interest in composites containing zirconia because of their high strength, fracture toughness, and its great influence on the chemical durability in glass. For the zirconia-silica system, monolithic glasses, fibers and coatings have been obtained. There is currently a great interest in designing zirconia-toughened alumina including exploration of the processing methods and the toughening mechanism.The possibility of forming nanocrystal composites by a phase separation method has been investigated in three systems: zirconia-alumina, zirconia-silica and zirconia-titania using HREM. The morphological observations initially suggest that the formation of nanocrystal composites by a phase separation method is possible in the zirconia-alumina and zirconia-silica systems, but impossible in the zirconia-titania system. The separation-produced grain size in silica-zirconia system is around 5 nm and is more uniform than that in the alumina-zirconia system in which the sizes of the small polyhedron grains are around 10 nm. In the titania-zirconia system, there is no obvious separation as was observed in die alumina-zirconia and silica-zirconia system.

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