Abstract: In various wellbore test systems, a probe mechanism that is extended to contact the formation within a wellbore, and retracted to allow movement of the test system, both rotationally and longitudinally, within the wellbore. A combination including monitoring an actuation fluid pressure used to actuate the probe mechanism to extend and to retract, and the use of one or more timers, provide information used to determine the position of the probe mechanism during the extension and retraction movements.

Abstract: Aspects of the subject technology relate to downhole sensing system are disclosed. The system has a first collar configured to accept a receiver, a second collar configured to accept a transmitter; and an acoustic isolator disposed between the first collar and the second collar. The acoustic isolator has a tubular body with a generally smooth exterior surface and an interior surface with a plurality of circumferential grooves formed in the interior surface that modify the acoustic impedance of the tubular body, thereby attenuating an acoustic signal passing through the tubular body.

Abstract: A process for the preparation of Isosulphan Blue is disclosed. The process comprises the following steps: Sulphonating orthochlorobenzaldehyde, treatment with sodium sulphite, basification, condensation and oxidation to obtain Isosulphan Blue.