Metrohm 746 VA Trace Analyzer - Manual (Page 358)

5.7.3 Alphabetical instruction list
746 VA Trace Analyzer / 747 VA Stand
5-207
Examples The first example shows a cadmium determination with proportional
standard addition as a function of the Cd content.
Method caseCd.mth OPERATION SEQUENCE
Title CASE program with proportional addition
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Instructions t/s Main parameters Auxiliary parameters
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1 SMPL>M V.fraction mL V.total L
2 (ADD . .
3 SEGMENT Segm.name Cd-det
4 (CASE EV:Cd <= 0 Calc.f. A01
5 CASE EV:Cd < 1e-9 Calc.f. A02
6 PADD>M Soln.name Cd-Std1 Prop.coeff. 8
Prop.subst. Cd
7 CASE EV:Cd >= 1e-9 Calc.f. A02
8 PADD>M Soln.name Cd-Std2 Prop.coeff. 0.05
Prop.subst. Cd
9 CASE) . .
10 EXIT EV:Cd <= 0
11 ADD)2 . .
12 END . .
Method caseCd SUBSTANCES
Cd - Cd-det
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Calibration 1993-11-12 09:39 Coefficients
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Technique std.add. Y.reg 4.371e–09
Curve type linear Slope 0.002408
Nonlin.
Mean dev. 1.836e–10
Additions
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Soln.name Cd-Std1 Cd-Std2
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Mass conc. 1 mg/L 100 mg/L g/L g/L
Range min g/L g/L g/L g/L
Range max g/L g/L g/L g/L
M.conc./cm g/L g/L g/L g/L .
Method caseCd CALCULATION
max. 15 lines
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Quantity Formula (R##, C##, A##) Res.unit Sig.dig.
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rho(Cd) A01 = MC:Cd no res. 2
rho(Cd) A02 = MC:Cd #g/L 5
This program runs as follows:
After the sample addition, first the segment Cd-det that provides EV:Cd
as an evaluation value is started. The remaining program run depends
on the testing of this result in the CASE block:
•
EV:Cd <= 0 (line 4)
If no evaluation was possible for the substance Cd , the value EV:Cd
is set to 0. In this case the alternative formula A01 is activated and
the CASE block quit, i.e. no standard addition takes place. Following
the CASE block, the
EXIT instruction with identical test condition is
used to exit the ADD loop immediately.