Abstract: A tank is fed with mud via a first inlet and the mud is removed via a first outlet. An ultrasonic electroacoustic transducer generates an acoustic energy field in the mud contained in the tank so as to extract the gases from the mud. A carrier gas is injected via a second inlet of the tank and a physico-chemical analysis apparatus of the extracted gases is connected to a second outlet of the tank designed for the carrier gas and the extracted gases. The flow rate of mud fed to the tank is regulated to a constant value and the volume of mud in the tank is constant. The mud can be constituted by oil prospecting drilling mud, the gases to be extracted then being oil revealing gases. The mud feed and injection of carrier gas can be synchronized so as to enable continuous analysis or batch analysis.

Abstract: The tank is fed with mud via a first inlet and the mud is removed via a first outlet. An ultrasonic electroacoustic transducer generates an acoustic energy field in the mud contained in the tank so as to extract the gases from the mud. A carrier gas is injected via a second inlet of the tank and a physico-chemical analysis apparatus of the extracted gases is connected to a second outlet of the tank designed for the carrier gas and the extracted gases. The flow rate of mud fed to the tank is regulated to a constant value and the volume of mud in the tank is constant. The mud can be constituted by oil prospecting drilling mud, the gases to be extracted then being oil revealing gases. The mud feed and injection of carrier gas can be synchronized so as to enable continuous analysis or batch analysis.

Abstract: A piezoactive motor has a stator equipped with independent stator modules 44, each comprising at least one pair of longitudinal piezoactive actuators 12, 14 colinearly arranged inside a mechanical coupling element 16 in the form of a shell 20. In addition, it is fixed by flexible decoupling links 68, 70 and comprises a central countermass 18. To produce a closed trajectory of the peaks (A and B) designed to cause by friction relative movement of a driven part over a large travel distance, and to position the driven part, these modules use separately or in combination:translational deformation, obtained when the piezoactive actuators are deformed in opposition and produce a tangential movement of the peaks (A and B) of the shell (20) relatively to the countermass (18), due to the mass ratio between the countermass and the shell,flexional deformation, obtained when the piezoactive actuators are deformed in the same way and produce a flexion of the shell (20), resulting in a normal movement of the peaks A and B.

Abstract: The stator of the motor comprises a support structure bearing at least one pair of transducers each including a vibrating element, the transducers being located colinearly and excited so their vibrating elements vibrate at one and the same frequency, but with a phase shift of 90.degree., and a coupling shell to which the vibrations are applied, and at least one rotor frictionally driven by the coupling shell. The coupling shell is of closed shape and is fixed at two opposed points on its major axis to the transducers. The resonance frequency of the coupling shell is the same in both vibration modes so that high efficiency is obtained.