Shimadzu PDA-7000, Инструкция по эксплуатации

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5 Maintenance
5-28
8 Repeat procedure 7 until the intensity matches the background intensity.
9 Press 2: Stop to stop the discharge.
10 Calculate the number to set the scanning dial at, from the profile curve on the
screen.
For example, the calculation in the case of the profile on the previous page is as
follows.
535 : The dial number right before the intensity hits the maximum.
547 : The estimated dial number at the intersection of the profile
curve and a perpendicular line from the point above. (in this
case 535)
11 Set and lock the scanning dial at the number calculated above.
Be sure to remove the backlash by the way described below.
Removing backlash
When turning the dial largely, first turn it to a value 20-30 lower than the target value.
Then turn the dial clockwise slowly to adjust at the intended position.
Note
● For elements with profile curve peaks which cannot be scanned every 5
graduations, such as internal standard elements Al 237.2nm, Al 266.0nm,
and Pb 322.0nm, calculation error may occur and accurate peak values
may not be obtained. In this case, create profiles using a sample with
content of 0.5 to 1% at Cu 327.4nm of the analysis line, and set the
scanning dial to the peak value calculated with the analysis line.
● When the calculated dial number is deviated more than ±2scales from the
original position, retry manual scanning.
Caution
Do not turn the scanning dial before unlocking .
It may damage the scanning dial.
535 + 547
Dial Number =
—————
2
= 541