NMR relaxation measurements in solid H2 at low ortho-H2 concentrations

1977 ◽  
Vol 28 (5-6) ◽  
pp. 415-441 ◽  
Author(s):  
Robert F. Buzerak ◽  
Moses Chan ◽  
Horst Meyer
Keyword(s):  
Nmr Relaxation ◽  
Relaxation Measurements

scholarly journals Freeze–Thaw Effect on Road Concrete Containing Blast Furnace Slag: NMR Relaxometry Investigations

Materials ◽  
2021 ◽  
Vol 14 (12) ◽  
pp. 3288
Author(s):  
Liliana Maria Nicula ◽  
Ofelia Corbu ◽  
Ioan Ardelean ◽  
Andrei Victor Sandu ◽  
Mihai Iliescu ◽  
...  
Keyword(s):  
Blast Furnace ◽  
Blast Furnace Slag ◽  
Nmr Relaxation ◽  
Invasive Technique ◽  
Freeze Thaw ◽  
Nmr Relaxometry ◽  
Main Technique ◽  
Relaxation Measurements ◽  
Furnace Slag ◽  
Standard Techniques

The present work investigates the effect of freeze–thaw cycles on the porosity of three mixtures of road concrete containing blast furnace slag in comparison with two mixtures made with conventional materials. The main technique used in our investigations is nuclear magnetic resonance (NMR) relaxometry. This permitted the extraction of information with respect to the freeze–thaw effect on pore-size distribution, which influences both the mechanical strength and the molecular transport through the material. Moreover, by using this technique, the structure of the air voids was analyzed for the entire pore system in the cement paste and the aggregate particles. The samples under study were first dried in a vacuum oven and then saturated with water or cyclohexane where the distribution of the transverse relaxation times of the protons was recorded. The NMR relaxation measurements were performed on samples extracted from specimens maintained at 300 freeze–thaw cycles and on control samples extracted from specimens kept in water during the freeze–thaw period. Scanning Electron Microscopy (SEM) was used to analyze the microstructure of concrete samples in order to obtain information about the pore sizes and the distance between them. The results from the NMR relaxation measurements were consistent with those obtained by using standard techniques for determining the porosity and the freeze–thaw resistances. The investigations made it possible to establish the optimal composition of blast furnace slag that can be incorporated into road concrete compositions. This non-invasive technique can also complete standard techniques for assessing the porosity and the progress of internal cracks during the freeze–thaw test.

Dipolar spectral densities from off-resonance 1H NMR relaxation measurements

1995 ◽  
Vol 233 (5-6) ◽  
pp. 545-549 ◽  
Author(s):  
H Desvaux ◽  
P Berthault ◽  
N Birlirakis
Keyword(s):  
1H Nmr ◽  
Nmr Relaxation ◽  
Spectral Densities ◽  
Relaxation Measurements

Enhancing signal-to-noise ratio and resolution in low-field NMR relaxation measurements using post-acquisition digital filters

2018 ◽  
Vol 57 (9) ◽  
pp. 616-625 ◽  
Author(s):  
Tatiana Monaretto ◽  
Andre Souza ◽  
Tiago Bueno Moraes ◽  
Victor Bertucci-Neto ◽  
Corinne Rondeau-Mouro ◽  
...  
Keyword(s):  
Digital Filters ◽  
Signal To Noise Ratio ◽  
Nmr Relaxation ◽  
Signal To Noise ◽  
Low Field ◽  
Relaxation Measurements ◽  
Low Field Nmr ◽  
Noise Ratio

Inversion of NMR Relaxation Measurements in Well Logging

2009 ◽  
pp. 501-517
Author(s):  
Lizhi Xiao ◽  
Guangzhi Liao ◽  
Ranhong Xie ◽  
Zhongdong Wang
Keyword(s):  
Nmr Relaxation ◽  
Well Logging ◽  
Relaxation Measurements

Biosynthetic13C Labeling of Aromatic Side Chains in Proteins for NMR Relaxation Measurements

2006 ◽  
Vol 128 (8) ◽  
pp. 2506-2507 ◽  
Author(s):  
Kaare Teilum ◽  
Ulrika Brath ◽  
Patrik Lundström ◽  
Mikael Akke
Keyword(s):  
Nmr Relaxation ◽  
Side Chains ◽  
Relaxation Measurements ◽  
Aromatic Side Chains

Probing the Backbone Dynamics of Oxidized and Reduced Rat Microsomal Cytochromeb5via15N Rotating Frame NMR Relaxation Measurements:  Biological Implications†

Biochemistry ◽  
1998 ◽  
Vol 37 (35) ◽  
pp. 12320-12330 ◽  
Author(s):  
Lucia Banci ◽  
Ivano Bertini ◽  
Christine Cavazza ◽  
Isabella C. Felli ◽  
Dionysios Koulougliotis
Keyword(s):  
Nmr Relaxation ◽  
Backbone Dynamics ◽  
Rotating Frame ◽  
Relaxation Measurements

Molecular Reorientation in Liquid Methanol

1991 ◽  
Vol 46 (1-2) ◽  
pp. 89-94 ◽  
Author(s):  
R. Ludwig ◽  
D. S. Gill ◽  
M. D. Zeidler
Keyword(s):  
Nmr Relaxation ◽  
Quadrupole Coupling Constant ◽  
Dipolar Interaction ◽  
Proton Relaxation ◽  
Coupling Constant ◽  
Relaxation Rates ◽  
Molecular Reorientation ◽  
Quadrupole Coupling ◽  
Relaxation Measurements ◽  
Recent Computer

AbstractOxygen-17 enriched methanol CD317OH was synthesized and 1H as well as 17O nmr relaxation rates were measured in the temperature range 180-310 K. By varying the 17O-content different contributions to the proton relaxation rate could be separated and from the 17O-H dipolar interaction contribution the correlation time of the OH bond was determined. These results are compared to recent computer simulation data. Additional deuteron relaxation measurements on CH3OD yielded the quadrupole coupling constant which increases with falling temperature. The 17O quadrupole coupling constant shows a similar trend with temperature but not as pronounced.

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