APPARATUS FOR AND METHOD OF NUCLEAR QUADRUPOLE TESTING OF A SAMPLE

摘要

Apparatus for Nuclear Quadrupole Resonance testing a remote sample containing a given species of quadrupolar nucleus comprises at least one probe (112) having a given maximum cross-sectional dimension; means (102) for applying excitation to the probe or at least one of the probes to excite nuclear quadrupole resonance for a selected range of distance of the sample from the or one such probe, the selected range being at least one tenth of the given maximum dimension of the probe or said one such probe, the apparatus being adapted to produce a non-uniform field over the selected range; and means (106) for detecting the resonance response signal from the sample via the probe or at least one of the probes; the excitation being such as would generate non-zero resonance response signals at all distances within the selected range.