Solidification of Helium
نویسندگان
چکیده
منابع مشابه
Melting and Solidification of Helium in Restricted Geometries
The processes of melt ing and s o l i d i f i c a t i o n a r e determined t o a l a r g e ex ten t by microscopic condit ions a t t h e l iqu id-so l id i n t e r f a c e . Theoret ical ca lcu la t ions and some d i r e c t o p t i c a l observations suggest t h a t t h e i n t e r f a c e f o r helium i s several atomic layers th ick . I n our own experiments on t h e s o l i d i f i c a t i ...
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Positively charged ions were produced in supercritical helium at temperatures from 6 to 10 K and up to 2 MPa using a corona discharge. Their mobility was measured via current-voltage curves, and the hydrodynamic radius was derived using Stokes law. An initial increase and subsequent decrease of hydrodynamic radius was observed and interpreted in terms of growth, compression and solidification o...
متن کاملAccurate characteristics of Helium in nano-channels
This article describes an accurate subPico flowmeter bifurcatedin to liquid and gas flowrates less than 1mol/s for both MEMS/NEMS and cryogenic technology applications. The MEMS/NEMS are described as either two Gauges (instrument), or quartz fluctuating forks, even if the liquid or gas flows through an element, as well as cryogenic technology consisting of arrays of e...
متن کاملHELIUM , SOLID 1 Helium , Solid
Helium was first solidified at the famous Kamerlingh Onnes low-temperature physics laboratories in Leiden by W. H. Keesom [1] on June 25, 1926. The initial experiments by Sir Francis Simon at Oxford University and by Keesom and their collaborators focused on the melting curve, the specific heat, and the thermal conductivity of solid helium as a test of our early understanding of solids. These m...
متن کاملModel Based Control of Solidification
In this paper, model based control of solidification is studied. A one-dimensional model that describes the dynamic response of the solidification rate for a pure substance is developed. The solidification of a metal column is controlled in order to solidify at a desired rate. The manipulated variable is the power to the heater at the top of the casting. A linear PI-controller is implemented an...
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ژورنال
عنوان ژورنال: Nature
سال: 1926
ISSN: 0028-0836,1476-4687
DOI: 10.1038/118081a0