| 摘要 |
1,193,468. Nuclear magnetic resonance magnetometers. COMMISSARIAT A L'ENERGIE ATOMIQUE. Aug. 15, 1967 [Aug. 23, 1966], No.37534/67. Addition to 1,137,302. Heading G1N. The nuclear magnetic resonance magnetometer described in the parent Specification is improved by providing four samples so that the magnetometer comprises two identical pairs of samples disposed along two axes at right angles to each other and arranged so that unwanted signals due to displacement or rotation of the magnetometer or due to parasitic electromagnetic fields cancel. A first electronic resonance line of a paramagnetic substance dissolved in one sample of each pair is saturated to produce absorption of energy at the nuclear resonance frequency while a second electronic resonance line of a paramagnetic substance dissolved in the other sample of each pair is saturated to produce stimulated emission of energy at the nuclear resonance frequency. As shown in Fig. 1, the samples are chosen so that the first and second electronic resonance lines are of the same frequency and a common oscillator 14 serves to saturate the electronic resonance lines of all four samples, 12a, 12b, 12c, 12d. Alternatively, Fig. 3 (not shown), the first and second electronic resonance lines may be of different frequencies. Measuring head construction. The samples are mounted within a non-magnetic casing, Fig. 2 (not shown), in a manner allowing adjustment of their positions. The coils 6, 8 are arranged concentrically around their respective samples. Potentiometer 22, Fig.1, enables the relative amount of feedback to coils 8 to be adjusted. A resonating cavity comprising silver foils disposed side by side on the external wall of each sample vessel is opaque to the electronic resonance frequency but transparent to the nuclear magnetic resonance frequency. Sample compositions. Suitable pairs of samples for Fig.1 embodiment are (a) ditertio-butylnitroxide (DTBN) in 50/50 water/acetone and triacetoneamine-nitroxide (TANO) in 70/30 water/ ethylene glycol, and (b) TANO as above and "tanoxine six" in water glycol mixture. For Fig.3 embodiment, all the samples may be DTBN as above. |
