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c/hplc·submitted 2 years ago by u/medutest_mel

purity — 19 things I got wrong before I got it right

Discussionbranch of 6 comments

purity — 19 things I got wrong before I got it right, which sounds obvious until you try to state the evidence for it. Area percent is the integrated area of your peak over the total integrated area at one wavelength on one gradient. Change any of those and the number changes without the sample changing. System…

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6 comments, started 2 years ago
u/canada_coverage311 points·2 years ago

report the method or do not report the number

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u/valeria_cardoso246 points·2 years ago

Correction: that is a tailing factor, not a plate count. Different diagnostics for different problems.

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u/cormac_roos64 points·2 years ago

Retention time shifted 0.4 minutes and I assumed the worst. It was the column temperature.

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u/joaquin_petrov192 points·2 years ago

axis labels or the trace is decoration

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u/medutest_mel152 points·2 years ago

That is area percent, not mass percent. The trace cannot give you the second one.

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u/joaquin_petrov79 points·2 years ago

Correcting myself upthread: I said the gradient was linear and looking again it has a hold in the middle.

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