Dionex ASE 150, Руководство оператора

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ASE 150 Operator’s Manual
32
Doc. 065207-02 9/08
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If a sample needs to be treated with acids stronger than the
concentrations listed in
Table 3-1 , pretreat the sample with the
concentrated acid before loading it into the cell. After the
pretreatment, mix the sample with ASE Prep CR Resin (P/N 080024)
to partially neutralize the acid to approximately 0.1 M. The sample
may need to be mixed with pelletized diatomaceous earth (DE)
(P/N 062819) to absorb water, depending on how much acid was used
to pretreat the sample.
For example, if a food sample is treated with 10 mL of 8 M HCl, mix
the liquid hydrolysate with 30 to 40 g of ASE Prep CR and 15 g of
DE. When the sample is thoroughly mixed, add it to the zirconium
cell.
(Do not use a stainless steel cell.) Use this ratio of acid to ASE
Prep CR whenever using strong acids for pretreatment of samples.
If you have any questions about compatibility of an acid or base,
please contact Dionex.
Guidelines for Sample Preparation with a Drying or Dispersing
Agent
The following mixtures are recommendations only; adjust the proportions
as required.
•
If the sample appears dry, use this mixture:
4 grams sample to 1 gram DE
Mix the sample and the DE thoroughly in a small bottle, beaker, or
mortar.
•
If the sample appears wet, use this mixture:
4 grams sample to 2 grams DE
Mix the sample and the DE thoroughly in a small bottle, beaker, or
mortar.
•
If the sample is pure liquid, use 5 grams sample to 3 grams DE.
Fill the cell with DE and then add the sample.
NOTE Certain pure liquid samples may be mixed with
drying or dispersing agents other than DE. For
a current list of approved materials, contact
Dionex.