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10 - B1 gradient methods

Published online by Cambridge University Press:  06 August 2010

William S. Price
William S. Price
Affiliation:
University of Western Sydney
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Summary

Introduction

Although having some distinct limitations (e.g., relatively weak gradients and poor directionality), B1-based measurements have some particular advantages over B0 gradient-based methods. However, B1-based techniques have so far received only limited usage and consequently in this chapter we provide only a cursory coverage of these techniques and the interested reader is referred to the pertinent reviews on the subject.

B1 gradients

B1 gradients are more complex than B0 gradients. Apart from purely technical considerations, there are three main differences between B0 and B1 gradients: (i) A B0 field couples only into the spin system along the z-axis, thus the effective gradient tensor is always truncated into an effective vector (see Section 2.2.2). Radio frequency fields, however, couple into the spin system from any orientation within the transverse plane. As a result the B1 gradient generally retains its tensor form when it couples into the spin system. (ii) When the same rf coil is used for both excitation and detection, any phase variation is cancelled during the measurement. But when an experiment involves two rf fields at the same frequency this cancellation no longer occurs and phase variations need to be considered. This spatial dependence of the phase difference between the two rf fields presents an additional complication (or opportunity). (iii) The third difference is that B1 fields are non-secular and so do not commute with internal Hamiltonians. Thus, unlike a B0 gradient, a B1 gradient cannot be treated additively with respect to internal Hamiltonians.

Type
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NMR Studies of Translational Motion
Principles and Applications
 , pp. 308 - 312
Publisher: Cambridge University Press
Print publication year: 2009

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References

Canet, D., Radiofrequency Gradient Pulses. In Encyclopedia of Nuclear Magnetic Resonance, ed. Grant, D. M. and Harris, R. K.. vol. 6. (New York: Wiley, 1996), pp. 3938–44.Google Scholar
Canet, D., Radiofrequency Field Gradient Experiments. Prog. NMR Spectrosc. 30 (1997), 101–35.CrossRefGoogle Scholar
Canet, D., Radiofrequency Field Gradients in NMR, Theory. In Encyclopedia of Spectroscopy and Spectrometry, ed. Lindon, J. C., Tranter, G. E., and Holmes, J. L.. vol. 3. (London: Academic Press, 2000), pp. 1937–44.Google Scholar
Humbert, F., Potentials of Radio-Frequency Field Gradient NMR Microscopy in Environmental Science. J. Ind. Microbiol. Biotechnol. 26 (2001), 53–61.CrossRefGoogle ScholarPubMed
Ardelean, I. and Kimmich, R., Principles and Unconventional Aspects of NMR Diffusometry. In Annual Reports on NMR Spectroscopy. ed. Webb, G. A.. vol. 49. (London: Academic Press, 2003), pp. 43–115.CrossRefGoogle Scholar
Cory, D. G., Laukien, F. H., and Maas, W. E., Double-Quantum-Filtered-COSY B1-Gradient Experiments. J. Magn. Reson. A 105 (1993), 223–9.CrossRefGoogle Scholar
Zhang, Y., Maas, W. E., and Cory, D. G., Analysis of Homonuclear RF Gradient NMR Spectroscopy. Mol. Phys. 86 (1995), 347–58.CrossRefGoogle Scholar
Maas, W. E., Laukien, F., and Cory, D. G., Coherence Selection by Radiofrequency Gradients. J. Magn. Reson. A 103 (1993), 115–17.CrossRefGoogle Scholar
Raulet, R., Escanyé, J.-M., Humbert, F., and Canet, D., Quasi-Immunity of B1 Gradient NMR Microscopy to Magnetic Susceptibility Distortions. J. Magn. Reson. A 119 (1996), 111–14.CrossRefGoogle Scholar
Dereppe, J. M., Moreaux, C., and Humbert, F., NMR Diffusion Measurements in Heterogeneous Media Using Pulsed Radio-Frequency Field Gradients. Microporous Mesoporous Mater. 21 (1998), 645–50.CrossRefGoogle Scholar
Humbert, F., Diter, B., and Canet, D., NMR Microscopy by Strong Radiofrequency-Field Gradients with Spatial Resolution Better Than Five Micrometers. J. Magn. Reson. A 123 (1996), 242–5.CrossRefGoogle Scholar
Karczmar, G. S., Twieg, D. B., Lawry, T. J., Matson, G. B., and Weiner, M. W., Detection of Motion Using B1 Gradients. Magn. Reson. Med. 7 (1988), 111–16.CrossRefGoogle ScholarPubMed
Dupeyre, R., Devoulon, Ph, Bourgeois, D., and Decorps, M., Diffusion Measurements Using Stimulated Rotary Echoes. J. Magn. Reson. 95 (1991), 589–96.Google Scholar
Solomon, I., Rotary Spin Echoes. Phys. Rev. Lett. 2 (1959), 301–2.CrossRefGoogle Scholar
Belmajdoub, A., Boudot, D., Tondre, C., and Canet, D., NMR Self-Diffusion Measurements Using a Radio-Frequency Field Gradient Combined with Water Signal Suppression. Application to the pH-Dependent Solubilization of Hydroxyquinoline in SDS Micellar Solutions. Chem. Phys. Lett. 150 (1988), 194–8.CrossRefGoogle Scholar
Canet, D., Diter, B., Belmajdoub, A., Brondeau, J., Boubel, J.-C., and Elbayed, K., Self-Diffusion Measurements Using a Radio-Frequency Field Gradient. J. Magn. Reson. 81 (1989), 1–12.Google Scholar
Humbert, F., Valtier, M., Retournard, A., and Canet, D., Diffusion Measurements Using Radiofrequency Field Gradient: Artifacts, Remedies, Practical Hints. J. Magn. Reson. 134 (1998), 245–54.CrossRefGoogle ScholarPubMed
Mischler, E., Humbert, F., and Canet, D., A One-Shot Diffusion Sequence Using a B1 Gradient. J. Magn. Reson. B 109 (1995), 121–5.CrossRefGoogle Scholar
Mutzenhardt, P. and Canet, D., Behavior of Longitudinal Spin Orders in NMR Measurements of Self-Diffusion Coefficients Using Radiofrequency Field Gradients. J. Chem. Phys. 105 (1996), 4405–11.CrossRefGoogle Scholar
Mischler, E., Humbert, F., Diter, B., and Canet, D., Measurement of One-Dimensional Spatially Resolved Self-Diffusion Coefficients and Longitudinal Relaxation Times with a Single B1 Gradient. J. Magn. Reson. B 106 (1995), 32–9.CrossRefGoogle Scholar
Kimmich, R., Simon, B., and Köstler, H., Magnetization-Grid Rotating-Frame Imaging Technique for Diffusion and Flow Measurements. J. Magn. Reson. A 112 (1995), 7–12.CrossRefGoogle Scholar
Valtier, M., Humbert, F., and Canet, D., Maps of Self-Diffusion Coefficients by Radiofrequency Field Gradient NMR Microscopy. J. Magn. Reson. 141 (1999), 7–17.CrossRefGoogle ScholarPubMed
Kuntz, J.-F., Trausch, G., Palmas, P., Mutzenhardt, P., and Canet, D., Diffusive Diffraction Phenomenon in a Porous Polymer Material Observed by NMR Using Radio-Frequency Field Gradients. J. Chem. Phys. 126 (2007), 134904-1–134904-6.CrossRefGoogle Scholar
Kimmich, R. and Ardelean, I., Intermolecular Multiple-Quantum Coherence Transfer Echoes and Multiple Echoes in Nuclear Magnetic Resonance. J. Chem. Phys. 110 (1999), 3708–13.CrossRefGoogle Scholar
Jerschow, A., Multiple Echoes Initiated by a Single Radio Frequency Pulse in NMR. Chem. Phys. Lett. 296 (1998), 466–70.CrossRefGoogle Scholar
Ardelean, I., Scharfenecker, A., and Kimmich, R., Two-Pulse Nutation Echoes Generated by Gradients of the Radiofrequency Amplitude and of the Main Magnetic Field. J. Magn. Reson. 144 (2000), 45–52.CrossRefGoogle ScholarPubMed
Ardelean, I., Kimmich, R., and Klemm, A., The Nutation Spin Echo and Its Use for Localized NMR. J. Magn. Reson. 146 (2000), 43–8.CrossRefGoogle ScholarPubMed
Scharfenecker, A., Ardelean, I., and Kimmich, R., Diffusion Measurements with the Aid of Nutation Spin Echoes Appearing after Two Inhomogeneous Radiofrequency Pulses in Inhomogeneous Magnetic Fields. J. Magn. Reson. 148 (2001), 363–6.CrossRefGoogle ScholarPubMed
Simon, B., Kimmich, R., and Köstler, H., Rotating-Frame-Imaging Technique for Spatially Resolved Diffusion and Flow Studies in the Fringe Field of RF Probe Coils. J. Magn. Reson. A 118 (1996), 78–83.CrossRefGoogle Scholar
Farrher, G., Ardelean, I., and Kimmich, R., Probing Four Orders of Magnitude of the Diffusion Time in Porous Silica Glass with Unconventional NMR Techniques. J. Magn. Reson. 182 (2006), 215–20.CrossRefGoogle ScholarPubMed

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  • B1 gradient methods
  • William S. Price, University of Western Sydney
  • Book: NMR Studies of Translational Motion
  • Online publication: 06 August 2010
  • Chapter DOI: https://doi.org/10.1017/CBO9780511770487.011
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  • B1 gradient methods
  • William S. Price, University of Western Sydney
  • Book: NMR Studies of Translational Motion
  • Online publication: 06 August 2010
  • Chapter DOI: https://doi.org/10.1017/CBO9780511770487.011
Available formats
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  • B1 gradient methods
  • William S. Price, University of Western Sydney
  • Book: NMR Studies of Translational Motion
  • Online publication: 06 August 2010
  • Chapter DOI: https://doi.org/10.1017/CBO9780511770487.011
Available formats
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