Abstract: The device is a transformer comprising a magnetic circuit (22) in the form of a closed frame having four parallel columns (23, 24, 25a, 25b) and two primary windings (26a, 26b), each arranged around an inner column of the frame (22). The windings (26a, 26b) are connected at one end to a first phase (P1) and a third phase (P3) respectively and at their other end to a second phase (P2) of the three-phase current source (27). The pipeline (28) comprises a closed circuit consisting of three branched tubular arms (29a, 29b, 29c), each passing through a gap between two columns (23, 24, 25a, 25b) of the frame of the magnetic circuit, the inner columns (25a, 25b) being surrounded by an electrical windings (26a, 26b).

Abstract: Ion cyclotron resonance is an important method used in mass spectroscopy. Examinations for determining the reactions between substances by means of the two-dimensional ICR method are carried out using the following measuring sequence:P.sub.1 -t.sub.1 -P.sub.2 -T.sub.m -P.sub.3 -t.sub.2,wherein P.sub.1, P.sub.2 and P.sub.3 are rf pulses, with the rf pulses P.sub.1 and P.sub.2 having the same frequency, t.sub.1 and T.sub.m are time intervals between the pulses and t.sub.2 is the observation time following the last pulse. This measuring sequence is repeated several times while varying t.sub.1. In this manner, a plurality of induction signals recorded during the time t.sub.2 is obtained, from which then a two-dimensional spectrum is derived by transformation from the time domain into the frequency domain. The transformation from the time domain to the frequency domain can be effected by two-dimensional Fourier transformation, or with the aid of the method of maximum entropy.