Impact of static-magnetic-field-gradients on relaxation times in a Rb vapor cell

2017 ◽  
Author(s):  
Mohammadreza Gharavipour ◽  
Christoph Affolderbach ◽  
Florian Gruet ◽  
Gaetano Mileti ◽  
Ivan S. Radojicic ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Static Magnetic Field ◽  
Relaxation Times ◽  
Vapor Cell ◽  
Field Gradients ◽  
Rb Vapor ◽  
Magnetic Field Gradients

Diffusion Imaging in the Presence of Static Magnetic-Field Gradients

1993 ◽  
Vol 104 (3) ◽  
pp. 273-282 ◽  
Author(s):  
A.J. Lucas ◽  
S.J. Gibbs ◽  
E.W.G. Jones ◽  
M. Peyron ◽  
J.A. Derbyshire ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Static Magnetic Field ◽  
Diffusion Imaging ◽  
Field Gradients ◽  
Magnetic Field Gradients

New perspectives of NMR in ultrahigh static magnetic field gradients

1994 ◽  
Vol 172-174 ◽  
pp. 674-681 ◽  
Author(s):  
Inyong Chang ◽  
Franz Fujara ◽  
Burkhard Geil ◽  
Gerald Hinze ◽  
Hans Sillescu ◽  
...  
Keyword(s):  
Magnetic Field ◽  
Static Magnetic Field ◽  
Field Gradients ◽  
Magnetic Field Gradients

Nuclear magnetic resonance microscopy

1989 ◽  
Vol 47 ◽  
pp. 828-829
Author(s):  
Paul C. Lauterbur
Keyword(s):  
Magnetic Field ◽  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Magnetic Fields ◽  
Signal To Noise ◽  
Field Gradients ◽  
Useful Signal ◽  
Magnetic Field Gradients ◽  
Observation Times ◽  
Nuclear Magnetic

Nuclear magnetic resonance imaging can reach microscopic resolution, as was noted many years ago, but the first serious attempt to explore the limits of the possibilities was made by Hedges. Resolution is ultimately limited under most circumstances by the signal-to-noise ratio, which is greater for small radio receiver coils, high magnetic fields and long observation times. The strongest signals in biological applications are obtained from water protons; for the usual magnetic fields used in NMR experiments (2-14 tesla), receiver coils of one to several millimeters in diameter, and observation times of a number of minutes, the volume resolution will be limited to a few hundred or thousand cubic micrometers. The proportions of voxels may be freely chosen within wide limits by varying the details of the imaging procedure. For isotropic resolution, therefore, objects of the order of (10μm) may be distinguished.Because the spatial coordinates are encoded by magnetic field gradients, the NMR resonance frequency differences, which determine the potential spatial resolution, may be made very large. As noted above, however, the corresponding volumes may become too small to give useful signal-to-noise ratios. In the presence of magnetic field gradients there will also be a loss of signal strength and resolution because molecular diffusion causes the coherence of the NMR signal to decay more rapidly than it otherwise would. This phenomenon is especially important in microscopic imaging.

PFG NMR and internal magnetic field gradients in plant-based materials

2002 ◽  
Vol 20 (7) ◽  
pp. 567-573 ◽  
Author(s):  
Nikolaus Nestle ◽  
Asal Qadan ◽  
Petrik Galvosas ◽  
Wolfgang Süss ◽  
Jörg Kärger
Keyword(s):  
Magnetic Field ◽  
Internal Magnetic Field ◽  
Field Gradients ◽  
Magnetic Field Gradients ◽  
Pfg Nmr
Sign in / Sign up

Export Citation Format

Share Document