Adixen ASM 142, Руководство пользователя

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A 401
About Helium and hydrogen
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Helium and leak
detection:
which purity ?
Helium is available in many different purity levels, the highest level of
purity is requested from some laboratories for fundamental activities or
very accurate analyses.
The use of the Helium as a tracer gas into a mass spectrometer
doesn’t require such attention. A purity in the range of 97 % to 99 %
is enough .
There is absolutely no risk of accuracy lost or contamination for the
cell analyzer by using standard purity level of Helium gas.
Hydrogen
Hydrogen (H
2
) is the lightest element, has a gaseous specific gravity
of 0.0695 and a boiling point of -423 °F (-252.8 °C) at atmospheric
pressure. It is a colorless, odorless, tasteless, flammable gas found at
concentrations of about 0.0001 % in air. Hydrogen is produced by
several methods, including steam/methane reforming, dissociation
of ammonia, and recovery from by-product streams from chemical
manufacturing and petroleum reforming. Hydrogen can be stored and
transported as a gas or a cryogenic liquid.
Hydrogen is flammable in the concentration range 4 % to 75 % in
air or oxygen and can detonate in the range 18 % to 60 % in air or
oxygen .
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