Magnetic resonance measurement methods for determining the mass of samples
are provided in which magnetic field homogeneity is determined,
compensation is provided for potential drifts in the measuring system,
and the presence of metal in samples is determined. The methods include
applying a magnetic field in a first direction in an interrogation zone
for creating a net magnetisation within a sample located within the
interrogation zone; applying an alternating magnetic field in a second
direction in the interrogation zone for temporarily changing the net
magnetisation of the sample located within the interrogation zone;
monitoring energy emitted by the sample as the net magnetisation of the
sample returns to its original state and generating an output signal
having a characteristic which is proportional to the energy emitted; and
comparing the output signal of the monitoring with other data.
