precession

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precession

[-sesh′ən]
Etymology: L, praecedere, to go before
a comparatively slow gyration of the axis of a spinning body such that the axis traces out a cone, caused by the application of a torque. The magnetic moment of a nucleus with spin experiences such a torque when inclined at an angle to an applied magnetic field, resulting in precession at the Larmor frequency.

precession

An MRI term for the relatively slow gyration of the axis of a spinning body, which traces out a conical configuration. Precision is caused by the application of a torque which tends to change the direction of the rotation axis and is continuously directed at right angles to the plane of the torque. The magnetic moment of a nucleus with spin will experience such a torque when inclined at an angle to the magnetic field, resulting in precession at the Larmor frequency.

pre·ces·sion

(prē-sesh'ŭn)
The secondary spin of magnetic movements around the main magnetic field.
References in periodicals archive ?
2) Hydrogen protons in a voxel that contains 100% fat will precess approximately 220 to 230 Hz slower than a voxel composed of 100% water, at 1.
I had nothing but pitot-static instruments and the good old peanut gyro, which already was starting to precess.
This makes the orbit of the planet precess (see Figure 1).
This tug would make the inner core precess - that is, make the spin axis slowly rotate in the opposite direction - which would produce magnetic changes in the outer core that damp the precession.
Frozen brain tissue samples from mice were homogenized in 5% glucose in distilled water by using grinding tubes (Bio-Rad Laboratories, Hercules, CA, USA) and adjusted to 10% (wt/vol) with TeSeE Precess 48 Ribolyser OGER (Bio-Rad) according to the manufacturer's instructions.
The original method is known under the name Overall Equipment Efficiency--OEE (Drstvensek, 2006), and is used to evaluate three key performance indicators; Availability, Productivity and Quality of production precess.
In these sequences, W&L protons will repeatedly precess in- and out-of-phase every 2.
That field then forces the arrow to wobble, or precess, as the shaft of an unsteady top does.
Prime Minister Harper had discussed this with us when he was in India and he has proven true to his words and the precess has been completed in a short period of eleven days.
3]He magnetic dipoles can be made to precess in the plane perpendicular to the magnetic field.