PerkinElmer PINAACLE 900 Series, Руководство по оборудованию и обслуживанию для клиентов

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Preparing Your Laboratory
cylinder air is to be used, it is important to specify compressed air rather
than breathing air (i.e. medical grade) or an unspecified form.
The use of air cylinders requires the use of a suitable dual-stage regulator. A
regulator for cylinders with a CGA 590 connection is available from PerkinElmer
(Part No. 03030264)
Acetylene:
Acetylene is used as fuel for flame operation.
For the overwhelming majority of analyses, acetylene is the preferred fuel gas with
AA spectrometers. Air/acetylene is the preferred flame for the determination of
about 35 elements by AA. The temperature of the air/acetylene flame is
approximately 2300 °C. For most air/acetylene flames, the acetylene flow used is
about 4 liters/min or 0.14 cubic feet/min. Using a heat-combustion value of 1,450
BTU per cubic foot, the heat given off would be approximately 12,300 BTU per
hour (3,600 W). An air/acetylene flame can be used with all PerkinElmer burner
heads but is most commonly used with the supplied 10-cm (4-inch) burner head.
Suitable acetylene typically has a minimum purity specification of 99.6% with the
actual assay being about 99.8%. In general, ordinary welding-grade acetylene is
adequate for most AA analyses, though sometimes a particular tank may be
contaminated. Special higher purity "atomic absorption" grade acetylene is also
available from some vendors, and its use is recommended when the available
welding-grade acetylene is not sufficiently pure.
A size 1A acetylene cylinder contains about 8,500 liters (300 cubic feet) of
acetylene and usually lasts about 30 hours of burning time with an air/acetylene
flame. The cylinder requires an acetylene pressure regulator, which can be
obtained from the supplier of the gas or from PerkinElmer (Part No. 03030106).
For safe operation, oxygen must NEVER be used with PerkinElmer
premix burner systems. !
Warning