A fast method for the measurement of diffusion coefficients: one-dimensional DOSY
β Scribed by Michael J. Thrippleton; Nikolaus M. Loening; James Keeler
- Publisher
- John Wiley and Sons
- Year
- 2003
- Tongue
- English
- Weight
- 148 KB
- Volume
- 41
- Category
- Article
- ISSN
- 0749-1581
- DOI
- 10.1002/mrc.1195
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β¦ Synopsis
Abstract
A new experiment for the singleβscan measurement of diffusion coefficients is presented. The principle is to introduce a spatial variation in the parameters of a conventional pulse sequence, so that all of the scans required to determine some physical parameter can be recorded simultaneously from different parts of the sample. The spectrum is acquired in the presence of a weak read gradient so that the resulting lineshapes contain the information required. The pulse sequence is described in detail and demonstrated on a sample containing three components; its advantages and limitations are discussed in relation to those of existing techniques. For uncrowded spectra with high signalβtoβnoise ratio, this experiment provides an order of magnitude reduction in experiment time compared with conventional methods and is likely to be of most benefit where samples are changing rapidly with time or where a long period of polarization, which may be difficult to reproduce accurately, prohibits the use of multipleβscan techniques. Copyright Β© 2003 John Wiley & Sons, Ltd.
π SIMILAR VOLUMES
For NMR probes equipped with pulsed field gradient coils, which are not optimized for gradient linearity, the precision and accuracy of experimentally measured translational diffusion coefficients are limited by the linearity of the gradient pulses over the sample volume. This study shows that the a
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