Determination Of Correction Values For Nanocolor Tube Tests - MACHEREY-NAGEL PF-12 Plus Handbuch

the intrinsic color or turbidity of the sample. All changes to the sample during analysis, such as
dilution or addition of chemicals that influence pH or redox potential, must be reproduced as in
the original analysis.
Plus
With the PF-12 , the measurement program for the correction value is started after the mea-
surement of the (turbid or colored) sample (value A) by pressing
inserting and measuring the correction value (value B). The corrected measurement result is
displayed and stored. For some tests it is necessary to measure an additional correction blank
value.
Underlying procedure:
Determine measured value according to test instruction = A
Determine correction value according to special instruction = B
Analysis result = A – B
Exceptions: Methods in which decreasing absorbance is measured against a reagent blank
value. Then the following applies: Analysis result = A + B. The corresponding special instruc-
tions point out this fact.
It is very important to subtract only values with equal dimensions (e.g. mg/L N; mg/L NH₄;
mmol/m³; A).
If the correction factor is so low in the same matrix with several samples that it is negligible
for the measurement problem at hand, the determination can be omitted. However, this only
results from practical testing and is not evident beforehand!
12.6 Determination of correction values for NANOCOLOR
When measuring the correction value, a clean, empty cuvette filled with distilled water is used
as the zero value
Test
0-01 Zirconium
0-02, 0-03, 0-04, 0-05, 0-06,
0-08 Ammonium 3 2000
0-07 AOX 3
0-09 Lead 5
0-14 Cadmium 2
0-15 Carbonate hardness 15
0-17 Chlorine / Ozone 2
0-18 Chlorine dioxide 5
0-19 Chloride 200
0-21 Chloride 50
0-24 Chromate 5
Tube for correction (value B)
Proceed as described in the test instructions for Test 0-01, but do not add
NANOFIX R2, seal, mix.
Proceed as described in the test instructions for test 0-02 / 0-03 / 0-04 / 0-05 /
0-06 / 0-08, but do not add NANOFIX R2, close, mix.
Almost all colors and turbidities are destroyed under test conditions and do
not interfere. Resistant colors and turbidities cause deviating results which
cannot be circumvented.
The original test already contains a correction.
Fill empty test tube with 4.0 mL sample, add 0.2 mL R2, close and mix.
Open carbonate hardness test tube, add 4.0 mL sample solution, close, mix
and adjust to zero (value B). Open test tube again, add NANOFIX R2, close
and shake well. Measure after 2 min (analytical result = A – B).
Fill empty test tube with 4.0 mL sample for each test.
Fill empty test tube with 4.0 mL sample for each test.
Open chloride test tube, add 1.0 mL sample solution and 1.0 mL distilled
water, close, mix.
Open chloride test tube, add 4.0 mL sample solution and 1.0 mL distilled
water, close, mix.
Fill empty test tube with 4.0 mL sample, add 0.2 mL R2, close, mix.
Manual Photometer PF-12
. The instrument requests
tube tests
®
Plus
EN, V2.00, 08.2021
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