Abstract: The device comprises a detector (15) of radiation that could be neutron radiation and a detector (16) of another type of radiation, for example gamma radiation. The process consists in deducing a burn up fraction or irradiation of the nuclear fuel (26) by the measurement of the measured value of a radiation, while assuming that the fuel has a defined composition. One deduces from this the activity of the other radiation that one should obtain, and the accuracy of the assumption of the composition of the fuel if the measured value is close to this deduced value. The device (1), which makes it possible to obtain satisfactory measurements in a water filled storage bay (26), is fitted with means for attaching it to a boom (3) and for positioning it (6, 9) in a given position on a fuel storage cell structure (4). The device is displaced towards each fuel element.

Abstract: Servocontrol is achieved on a radiation detector that controls a motor (7) that makes a rod (9) slide, tilting a mobile portion (12) of an absorbing enclosure (2) to open or close a collimation slit (3) and adjust the amount of radiation received by the detection solid (1) to an ideal value for measurement precision. This device can be used particularly in gamma spectrometry.

Abstract: Servocontrol is achieved on a radiation detector that controls a motor (7) that makes a rod (9) slide, tilting a mobile portion (12) of an absorbing enclosure (2) to open or close a collimation slit (3) and adjust the amount of radiation received by the detection solid (1) to an ideal value for measurement precision.

Abstract: Novel farnesyl transferase inhibitors of general formula (I), ##STR1## the preparation thereof and pharmaceutical compositions containing said inhibitors, are disclosed. In general formula (I), R.sub.1 is Y--S--A.sub.1 (where Y is a hydrogen atom, an amino acid residue, a fatty acid residue, an alkyl or alkoxycarbonyl radical or a radical R.sub.4 --S-- where R.sub.4 is a C.sub.1-4 alkyl radical optionally substituted by a phenyl radical or a radical of general formula (II) ##STR2## wherein A.sub.1, X, X.sub.1, Y.sub.1, R'.sub.1, R.sub.2, R'.sub.2 and R are defined as below, and A.sub.1 is a C.sub.1-4 alkylene radical optionally alpha-substituted in the >C(X.sub.1)(Y.sub.1) grouping by an amino or alkylamino, dialkylamino, alkanoylamino or alkoxycarbonylamino radical); X.sub.1 and Y.sub.1 are each a hydrogen atom or, taken together with the carbon atom to which they are attached, form a >C.dbd.O grouping; R'.sub.1 is hydrogen or a C.sub.1-6 alkyl radical; X is an oxygen or sulphur atom; R.sub.2 is a C.