INST No INE -403-0P0
−
28
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7.2.2 Paper (Sheet substance)
(I) Weigh the weight w
1
of a sample before measurement.
(2) Hold the sample by a paper holder, put it by tilting at 15º to the measuring position, set
the calibration curve number to 0, and read its display (absorbance "x"). In this case,
match its front and back surfaces and flow direction of the samples.
(3) Weigh the weight w
2
of the sample after measurement. Perform the measurement from
(1) to (3) as quickly as possible.
(4) Perform the same measurement sequentially for all samples.
(S) Put each sample into a dryer, and dry it out to be the absolute dry condition (for longer
than 2 hours at 105ºC usually by using paper stand).
(6) Cool down all samples in a desiccator containing silica gel after drying.
(7) Weigh the weight w
3
of each sample.
(8) Record the measured value in the following table every measurement, and obtain the
moisture value by the following formula.
No. Absorbance "x" w0
W1
w2
Moisture value (%H
2
O)
1
x1
y1
2
x2
y2
3
:
x3
:
y3
:
N
xn
y4
7.2.3 Liquid
Execute the measurement in order from the object of low moisture to the object of high
moisture.
1) Put a sample into the measuring cell, set the calibration curve number to 0, and read the
display (absorbance "x").
If the measured value cannot be read easily, delay the response by the smoothing function.
2) With the Karl Fischer method or other methods, measure moisture value of the sample put
in the measuring cell.
3) Repeat the above measurements of 1) and 2) for 2 or 3 times per sample.
4) Record the measured value of all samples by the same measuring procedure in the
following table, and obtain the average value.
Absorbance "x"
No.
1
2
3
Average
Moisture
(%H
2
O)
1
x1
y1
2
x2
y2
3
:
x3
:
y3
:
N
xn
y4
(
w
1+
w
2)/2-
w
3
(
w
1+
w
2)
×１００
(%H
2
O)
・
For taking out a sample from a container, shake the container well to
uniform the moisture in the container and then take the sample out.
・
When the next sample is measured, throw away the sample already
contained completely and wash the measurement cell for two or
three times for the next measurement.
C a u t i o n
7. Preparation of calibration curves
