Laboratory installation for measurement of liqud vapor diffusion coefficients in gases

Precise measurements of temperature and density distributions in snow under an applied temperature gradient showed that alternation of evaporation and condensation zones is formed and causes the wavy patterns in quasi-steady temperature and density distributions. In samples with a snow density of 200–500 kg2m−3the wavelength was 3–7 cm and the amplitude was roughly 2°C. The present result gives a clue to explaining the wide range of previously measured water-vapor diffusion coefficients in snow.

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Wavy temperature and density distributions formed in snow

Annals of Glaciology ◽

10.3189/1998aog26-1-73-76 ◽

1998 ◽

Vol 26 ◽

pp. 73-76

Author(s):

Sergey A. Sokratov ◽

Norikazu Maeno

Keyword(s):

Water Vapor ◽

Temperature Gradient ◽

Diffusion Coefficients ◽

Snow Density ◽

Steady Temperature ◽

Vapor Diffusion ◽

Density Distributions ◽

Evaporation And Condensation ◽

Wide Range ◽

Measured Water

Precise measurements of temperature and density distributions in snow under an applied temperature gradient showed that alternation of evaporation and condensation zones is formed and causes the wavy patterns in quasi-steady temperature and density distributions. In samples with a snow density of 200–500 kg2 m−3 the wavelength was 3–7 cm and the amplitude was roughly 2°C. The present result gives a clue to explaining the wide range of previously measured water-vapor diffusion coefficients in snow.

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Water Vapor Diffusion in Relatively Dry Soil: IV. Temperature and Pressure Effects on Sorption Diffusion Coefficients

Soil Science Society of America Journal ◽

10.2136/sssaj1965.03615995002900020011x ◽

1965 ◽

Vol 29 (2) ◽

pp. 144-148 ◽

Cited By ~ 12

Author(s):

Ray D. Jackson

Keyword(s):

Water Vapor ◽

Diffusion Coefficients ◽

Pressure Effects ◽

Vapor Diffusion ◽

Water Vapor Diffusion ◽

Dry Soil ◽

Temperature And Pressure ◽

Temperature And Pressure Effects

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Interlayer mixing in GaAs/AlxGa1-xAs heterostructures as a result of Se+ ion implantation

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100106600 ◽

1988 ◽

Vol 46 ◽

pp. 908-909

Author(s):

E.G. Bithell ◽

W.M. Stobbs

Keyword(s):

Ion Implantation ◽

Diffusion Coefficients ◽

Dark Field ◽

Atomic Mass ◽

Composition Profile ◽

Semiconductor Heterostructures ◽

Transmission Electron ◽

Microscope Images ◽

Damage Process ◽

Electron Energy Loss

It is well known that the microstructural consequences of the ion implantation of semiconductor heterostructures can be severe: amorphisation of the damaged region is possible, and layer intermixing can result both from the original damage process and from the enhancement of the diffusion coefficients for the constituents of the original composition profile. A very large number of variables are involved (the atomic mass of the target, the mass and energy of the implant species, the flux and the total dose, the substrate temperature etc.) so that experimental data are needed despite the existence of relatively well developed models for the implantation process. A major difficulty is that conventional techniques (e.g. electron energy loss spectroscopy) have inadequate resolution for the quantification of any changes in the composition profile of fine scale multilayers. However we have demonstrated that the measurement of 002 dark field intensities in transmission electron microscope images of GaAs / AlxGa1_xAs heterostructures can allow the measurement of the local Al / Ga ratio.

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