Sample Preparation - Macherey-Nagel PF-12Plus Manual

8. Sample preparation

Water samples are not always suitable for immediate analysis. In case of heavily polluted
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interfere and lead to false negative or false positive test results.
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7KH FUDFN VHW 5()   DQG NANOCOLOR NanOx are used for oxidative treatment
of samples in an acidic medium under normal pressure at 100–120 °C. These methods are
easy to handle and solve a large number of decomposition problems.
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gen, total phosphorus and total chromium, we recommend oxidative decomposition with
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NANOCOLOR NanOx at elevated pressures in a microwave oven.
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a beaker, heat almost to dryness (use fume cupboard with fan on). As soon as a white SO -
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fog appears, stop heating and allow the deposit to cool down to room temperature, then
add 20 mL distilled water. Neutralise with sodium hydroxide solution and pour sample into a
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water. Almost all metals can be determined directly from this solution.
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sample preparation method. Always keep in mind that after the sample preparation has
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accurate statement with regards to the concentration once the actual analysis has been
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As can be deduced from this brief explanation, each analysis has to be treated individually
and the sample prepared accordingly in case of polluted samples. Only thus accurate and
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any questions.
For detailed instructions for the different decomposition methods and their applicability
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09.12.2014