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Pulsed field gradient spin-echo

We finish this section by comparing our results with NMR and incoherent neutron scattering experiments on water dynamics. Self-diffusion constants on the millisecond time scale have been measured by NMR with the pulsed field gradient spin echo (PFGSE) method. Applying this technique to oriented egg phosphatidylcholine bilayers, Wassail [68] demonstrated that the water motion was highly anisotropic, with diffusion in the plane of the bilayers hundreds of times greater than out of the plane. The anisotropy of... [Pg.492]

Pulse Field Gradient Spin Echo-Nuclear Magnetic Spectroscopy Pyridyl... [Pg.230]

Modem NMR diffusion measurements are all based on the Stejskal-Tanner (S-T) pulsed field gradient spin-echo experiment [174] in which a gradient pulse is... [Pg.339]

Proton-driven spin diffusion Pulsed field gradient spin-echo Pleckstrin homology Poly(hydroxyethylmethacrylate)... [Pg.4]

Abbreviations D, self-diffusion coefficient ge, gradient-echo IR, inversion recovery IRFT, inversion recovery fourier transform MRS, magnetic resonance spectroscopy PD, proton density PFGSE, pulsed field gradient spin echo se, spin-echo. [Pg.81]

A(g) is the signal intensity observed with an applied gradient g, A(0) is the intensity in the absence of an applied gradient, y is the nuclear gyromagnetic ratio, and (5 and A are time intervals of the pulsed field gradient spin—echo sequence. [Pg.333]

OPPOSE double pulsed field gradient spin echo... [Pg.313]

Umecky, T, Kanakubo, M., and Ikushima, Y., Self-diffusion coefficients of l-butyl-3-methylimidazolium hexafluorophosphate with pulsed-field gradient spin-echo NMR technique. Fluid Phase Equilib., 228-229, 329, 2005. [Pg.369]

By the pulsed field gradient spin echo method (1) it is possible to measure mean diffusion lengths ( /(l2)) for molecules in a given time interval in systems without a concentration gradient. The application of the method is limited to... [Pg.434]

Diffusion measurement using pulsed-field-gradient spin echoes (PGSE)... [Pg.129]

Toonkool, P., Regan, D. G., Kuchel, P. W., Morris, M. B., and Weiss, A. S. (2001a). Thermodynamic and hydrodynamic properties of human tropoelastin. Analytical ultracentrifuge and pulsed field-gradient spin-echo NMR studies. / Biol. Chem. 276, 28042-28050. [Pg.460]

The Pulsed Field Gradient Spin Echo (PFGSE)... [Pg.307]

We saw in Chapter 8 how a selective 180° pulse can be placed between two gradients of the same sign and duration to give a pulsed field gradient spin echo (PFGSE) that not only selects the desired coherence but also destroys any other coherences. First, we use a hard 90° pulse to create coherence on all spins, and then the first gradient twists the coherence into a helix (Fig. 8.21). The selective 180° pulse reverses the direction of twist in... [Pg.493]

Gao, P. and Fagerness, P., Diffusion in HPMC gels. I. Determination of drug and water diffusivity by pulsed-field-gradient spin-echo NMR, Pharmaceutical Research, Vol. 12, No. 7, 1995, pp. 955-964. [Pg.388]

Using pulsed field gradient spin echo NMR, Guering and Lindman [14] and, independently, Clarkson et al. [15] measured the self-diffusion coefficients of the components of microemulsions of sodium dodecyl sulfate (SDS), toluene, butanol, and NaCl brine. The results (Fig. 8) establish unequivocally the existence of bicontinous microemulsion. [Pg.178]

FIGURE 9.3 Pulse sequence for measurement of diffusion coefficient D by the pulsed field gradient spin echo technique. The gradient G is applied for a period 8 both before and after the 180° pulse, with separation A. [Pg.234]

Pulsed Field Gradient—Spin Echo (PGSE) Diffusion Spectroscopy... [Pg.6185]

The double pulsed field gradient spin echo (DPFGSE) pulse sequence has been used to improve the measurement of proton-proton nuclear Overhauser effect (NOE) [28]. The DPFGSE NOE does not rely on difference spectroscopy and very small NOEs can be measured. This technique has been used to determine the structure of organosilicon compounds [28]. [Pg.22]


See other pages where Pulsed field gradient spin-echo is mentioned: [Pg.125]    [Pg.439]    [Pg.19]    [Pg.312]    [Pg.56]    [Pg.281]    [Pg.733]    [Pg.119]    [Pg.333]    [Pg.436]    [Pg.332]    [Pg.211]    [Pg.181]    [Pg.99]    [Pg.129]    [Pg.152]    [Pg.309]    [Pg.161]    [Pg.134]    [Pg.434]    [Pg.669]    [Pg.116]   
See also in sourсe #XX -- [ Pg.307 , Pg.493 ]




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Double-pulsed field gradient spin echo

Double-pulsed field gradient spin echo DPFGSE)

Field gradient

Field pulses

Field-gradient spin-echo

Gradient pulse

Gradient pulsed

Gradient-echo

Nuclear magnetic resonance pulsed-field gradient spin-echo

PFGSE (pulsed field gradient spin echo

Pulse Spin-echo

Pulse echo

Pulse field gradient

Pulse field gradient spin echo DPFGSE

Pulse field gradients, pulsed

Pulse gradient spin echo

Pulse-field-gradient spin-echo

Pulse-field-gradient spin-echo

Pulse-field-gradient spin-echo technique

Pulsed field gradient

Pulsed field gradient spin-echo NMR

Pulsed field gradient spin-echo experiment

Pulsed fields

Pulsed gradient spin-echo

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