Non stable Absorbance value using Perkin Elmer lambda 40 ?

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How to resume a Gate (geant4) simulation after a crash or power failure?

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What do you think about the expulsion of 21 teachers in Jordan university ?

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Adam B Shapiro

The absorbance is too high, above the useful range of the instrument. Try it again with one-tenth the concentration. If the result is still unstable, it could be that the lamp needs to be replaced, or there are air bubbles in the sample, or there is "stuff" floating around in the sample, or the sample volume is too low, or the sample is turbid (cloudy).

Rachid Lamari

Thank you so much Mt.Adam B Shapiro

The problem was as you mentioned..

Paul Milham

Well done Adam!! Paul.