field gradient

(redirected from magnetic field gradient)
Also found in: Medical.

field gradient

[′fēld ‚grād·ē·ənt]
(physics)
A vector obtained by applying the del operator to a scalar field.
A tensor obtained by dyadic multiplication of the del operator with a vector field.
References in periodicals archive ?
The column consists of steel wool which increases the magnetic field gradient to maximize separation efficiency when the column is placed between the permanent magnets.
While analyzing the magnetic memory signal of a metal structure, the extent of corrosion damage on the metal surface can be effectively measured with changes of magnetic field gradient: the greater the changes of magnetic field gradient are, the more serious the corrosion damage is [39, 40].
The principle of MNP transport is based on the magnetic polarization and magnetophoretic mobility when an external magnetic field gradient is applied [2].
Applied magnetic field and magnetic field gradient together with the vascularization of target region are particularly important when considering the distance from the magnets to the locations where particles are still effectively captured [8].
Axial gradient of the magnetic field gradient (dB/dL) at the wall of the channel, which caused oxygen transfer towards the pellet surface was equal to 1.56 T/m, but it was not higher than 0.8 T/m in the central part of the flame.
Iimoto, "Control of chemical reaction involving dissolved oxygen using magnetic field gradient," Chemical Physics, Vol.
To perform the spectroscopy of the bouncing neutron, the interaction that couples different quantum states can be a vibration of the bottom mirror or an oscillating magnetic field gradient [8].
While in [20] each data point was measured once the entire RF pulse is played out, in the present theoretical study (Section 2.1) we assumed that the data points are measured during the RF pulse, akin to the continuous MR signal reception during the application of a readout magnetic field gradient. In practice, concurrent transmission and reception could, for instance, be accomplished by transmitting a series of narrow (rectangular) RF bursts and measuring the MR signal in between the bursts, that is, during the time when the RF transmitter chain is switched off or blanked.
For this purpose magnetic nanoparticles have several advantages such as particle size and large surface area which can be properly modified to attach with biological agents, in addition having magnetic response so that they can be manipulated by an external magnetic field gradient; this technique is called magnetofection based on the principles developed by Widder in the 70s and its principle is to couple genetic material to nanoparticles; the efficacy has been demonstrated in a variety of cells [1].
There will be a force drawing the steel sphere into the centre of the gap, since there exists a magnetic field gradient in every direction away from this center-point.
If there simultaneously exists a magnetic field gradient during the MRI, this movement of the axon causes the spins to diphase, resulting in an artifact in the magnetic resonance signal.