scholarly journals Rotation-induced recovery and bleaching in magnetic resonance

2015 ◽  
Vol 17 (9) ◽  
pp. 6415-6422 ◽  
Author(s):  
Angel J. Perez Linde ◽  
Srinivas Chinthalapalli ◽  
Diego Carnevale ◽  
Geoffrey Bodenhausen
Keyword(s):  
Relaxation Time ◽  
Magnetic Resonance ◽  
Spin Relaxation ◽  
Sharp Decrease ◽  
Proton Spin ◽  
Spin Relaxation Time ◽  
Magic Angle

A sharp decrease of the longitudinal proton spin relaxation time T1(1H) is observed at 100 K when frozen mixtures of glycerol and H2O doped with lanthanides are made to rotate slowly about the magic angle, in a manner that is reminiscent of spin refrigerators.

1093 SENSITIVITY OF MAGNETIC RESONANCE PROTON SPIN-SPIN RELAXATION TIME AS AN INDEX OF MUSCLE ACTIVATION

1994 ◽  
Vol 26 (Supplement) ◽  
pp. S194
Author(s):  
G. Yue ◽  
A. L. Alexander ◽  
D. H. Laidlaw ◽  
A. F. Gmitro ◽  
E. C. Unger ◽  
...  
Keyword(s):  
Relaxation Time ◽  
Magnetic Resonance ◽  
Spin Relaxation ◽  
Muscle Activation ◽  
Proton Spin ◽  
Spin Relaxation Time

Proton spin-spin relaxation time of peel and flesh of navel orange varieties exposed to freezing temperature

2005 ◽  
Vol 85 (14) ◽  
pp. 2482-2486 ◽  
Author(s):  
Prem N Gambhir ◽  
Young J Choi ◽  
David C Slaughter ◽  
James F Thompson ◽  
Michael J McCarthy
Keyword(s):  
Relaxation Time ◽  
Spin Relaxation ◽  
Freezing Temperature ◽  
Proton Spin ◽  
Spin Relaxation Time ◽  
Navel Orange

Slow Motion of Confined Molecules: NMR and Broadband Dielectric Spectroscopy Investigations

2008 ◽  
Vol 8 (2) ◽  
pp. 887-893 ◽  
Author(s):  
Özlen F. Erdem ◽  
André Pampel ◽  
Dieter Michel
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Ethylene Glycol ◽  
Spin Relaxation ◽  
Dielectric Spectroscopy ◽  
Proton Spin ◽  
Magic Angle ◽  
Glass Forming ◽  
Broadband Dielectric Spectroscopy ◽  
Nuclear Magnetic

Nuclear magnetic resonance (NMR) and broadband dielectric spectroscopy are used to investigate the dynamics of small glass-forming molecules confined to restricted geometries. Ethylene glycol molecules are embedded in the supercages of NaX zeolites. The combined application of NMR and broadband dielectric spectroscopy advances the understanding of the slowing down of the motion near the glass transition temperature of these confined molecules. In combination with nuclear spin relaxation and nuclear magnetic resonance spectroscopy, dielectric relaxation studies on glass forming molecules allow conclusions on the character of the motion. High resolution 1H magic angle spinning (MAS) NMR measurements not only enable a characterisation of the state of the adsorbed molecules via a chemical shift analysis. By means of an analysis of MAS spinning sidebands we may also estimate a correlation time the meaning of which will be discussed in comparison to the results of longitudinal proton spin relaxation measurements. In addition to broadband dielectric spectroscopy slow molecular motions of partially deuterated ethylene glycol adsorbed in NaX are studied by means of 2H NMR line-shape analysis.

scholarly journals Influence of drying–wetting cycles on soil-water characteristic curve of undisturbed granite residual soils and microstructure mechanism by nuclear magnetic resonance (NMR) spin-spin relaxation time (T2) relaxometry

2018 ◽  
Vol 55 (2) ◽  
pp. 208-216 ◽  
Author(s):  
Lingwei Kong ◽  
Hossain Md. Sayem ◽  
Huihui Tian
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Relaxation Time ◽  
Magnetic Resonance ◽  
Size Distribution ◽  
Soil Water ◽  
Spin Relaxation ◽  
Characteristic Curve ◽  
Spin Relaxation Time ◽  
Residual Soils ◽  
Soil Water Characteristic Curve

Due to the formational environment and climatic variability, granite residual soils with grain-size distribution ranging from gravel to clay undergo multiple drying–wetting cycles. The influences of multiple drying–wetting cycles on the soil-water characteristic curve (SWCC) and pore-size distribution (POSD) of undisturbed granite residual soils are investigated using the pressure plate test and nuclear magnetic resonance (NMR) spin-spin relaxation time (T2) distribution measurement, respectively. Results show that the water-retention capacity and air-entry value decrease and pores become more uniform with increasing drying–wetting cycles. After four drying–wetting cycles, the soil reaches a nearly constant state. The POSD change of multiple drying–wetting cycle samples is consistent with the SWCC of the soils. Furthermore, a modified van Genuchten model in terms of cumulative pore volume is used to obtain the best-fit POSD of the drying–wetting cycle samples. The shape and changing tendency of both curves of SWCC and POSD are quite similar and achieved a better correlation. It can be concluded that the SWCC is strongly dependent on the POSD of the soil and NMR T2 relaxometry can be used as an alternative to the assessment of microstructural variation of residual soils subjected to the periodic drying and wetting process.

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