Mass And Volume Specific Measurements; Taking Measurements - Bartington MS2 Operation Manual

Note: When operated on the x0.1 range, the diamagnetic contribution (-ve sign) may
become significant due to the material of the sample holder. This should be measured
separately for an empty container, and the value subtracted from subsequent readings.
i.e. R = R
sample meas

6.7. Mass and Volume Specific Measurements

The density of most sample materials will be their bulk density. Due to their granular nature and
the inclusion of air, this will almost always be less than the 'true' density.
Except in the case of rock samples, conversion from mass to volume units is not possible unless
the true density can be established by, for example, compacting the material to a solid at great
pressure.
6.7.1. Mass Specific Measurements
The sensor is calibrated for a sample mass of 10g. Mass specific measurements are the
preferred method of expressing measurements using this sensor. For dry materials, and for
materials of unknown density, this provides the most useful measurement because simple
weighing of the material is all that is required. Where sample mass departs from calibration
mass the corrected value will be:
c = measured value x calibration mass/sample mass
Therefore it will be usual to weigh the samples carefully prior to taking measurements.
Example: cal. mass = 10g., sample mass = 12g. c
6.7.2. Volume Specific Measurements
Where comparison only between identically prepared samples is required, or where it is not
desired to dry out wet samples, then 'volume' susceptibility can be recorded directly. Where
sample volume departs from calibration volume, the corrected value will be:
k = measured value x calibration volume/sample volume. (See

6.8. Taking Measurements

At this stage the samples should have been correctly labelled and weighed, and the operator
should be familiar with the calculations given in the previous section.
Note: Time should have been allowed for the samples and sensor to thermally equilibrate
to room temperature.
BARTINGTON INSTRUMENTS
- R
container
Page 26 of 82
= c
./1.2
true meas
Table 3 below.)
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