6. Magnetic resonance and coupling effects in metallic metamaterials

2015 ◽  
pp. 231-270
Keyword(s):  
Magnetic Resonance ◽  
Coupling Effects

scholarly journals Cross-Axis Coupling Effects in Single-Axis Nuclear Magnetic Resonance Gyroscopes

Sensors ◽  
2020 ◽  
Vol 20 (3) ◽  
pp. 734
Author(s):  
Zhiguo Wang ◽  
Yi Zhang ◽  
Xiang Zhan ◽  
Qiyuan Jiang ◽  
Hui Luo
Keyword(s):  
Magnetic Field ◽  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Vibration Frequency ◽  
Coupling Effects ◽  
Rotation Rates ◽  
Angular Vibration ◽  
The Cross ◽  
Cross Axis ◽  
Nuclear Magnetic

Nuclear magnetic resonance gyroscopes (NMRGs) may be operated in an environment with violent vibration that usually contains both linear components and angular components. To analyze the influence of angular vibration on an NMRG, cross-axis coupling effects are studied. The cross-axis rotation rates induce an equivalent magnetic field. Its influence can be described by the Bloch equations. The approximate frequency shift and amplitude of the spin oscillator with an equivalent magnetic field in the cross-axis were obtained, which was validated by numerical simulation. The findings show that the angular vibration component leads to a remarkable error for the NMRG. When the angular vibration frequency is near the Larmor frequency, the oscillation frequency of the spins may be locked to the angular vibration frequency, destroying the NMRG’s ability to measure rotation rates. The cross-axis coupling problem should be considered in the design of an NMRG and corresponding inertial navigation systems.

Proton magnetic resonance spectra of some β-methylstyrenes, β,β-dimethylstyrenes, and α-methylstilbenes; and a discussion of long-range shieldingand coupling effects in these and related systems

1965 ◽  
Vol 18 (11) ◽  
pp. 1759 ◽  
Author(s):  
H Rottendorf ◽  
S Sternhell ◽  
JR Wilmshurst
Keyword(s):  
Magnetic Resonance ◽  
Long Range ◽  
Proton Magnetic Resonance ◽  
Coupling Constants ◽  
Coupling Effects ◽  
Styrene Derivatives ◽  
Shielding Effects ◽  
Magnetic Resonance Spectra

The preparation of some new β,β-dimethylstyrenes and α-methylstilbenes is described and their p.m.r. spectra are reported. The long-range shielding effects in β,β-dimethylstyrenes and other styrene derivatives are discussed. The differences between the cisoid and transoid allylic coupling constants in β,β-dimethylstyrenes are much smaller than the corresponding differences in simple propenes. No appreciable (J ≥ 0.3 c/s) coupling between the non-equivalent methyl protons in β,β-dimethylstyrenes has been observed. Long-range coupling in the compounds investigated appears to be independent of ring substitution. Some general features of allylic coupling are discussed.

An emerging technology: Nuclear magnetic resonance microscopy

1988 ◽  
Vol 46 ◽  
pp. 1000-1001
Author(s):  
M.J. Hennessy ◽  
E. Kwok
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Magnetic Resonance ◽  
Relaxation Times ◽  
Basic Research ◽  
Local Environment ◽  
Magnetic Resonance Images ◽  
Nmr Microscopy ◽  
Mri Scans ◽  
Temperature Relaxation ◽  
Nuclear Magnetic

Much progress in nuclear magnetic resonance microscope has been made in the last few years as a result of improved instrumentation and techniques being made available through basic research in magnetic resonance imaging (MRI) technologies for medicine. Nuclear magnetic resonance (NMR) was first observed in the hydrogen nucleus in water by Bloch, Purcell and Pound over 40 years ago. Today, in medicine, virtually all commercial MRI scans are made of water bound in tissue. This is also true for NMR microscopy, which has focussed mainly on biological applications. The reason water is the favored molecule for NMR is because water is,the most abundant molecule in biology. It is also the most NMR sensitive having the largest nuclear magnetic moment and having reasonable room temperature relaxation times (from 10 ms to 3 sec). The contrast seen in magnetic resonance images is due mostly to distribution of water relaxation times in sample which are extremely sensitive to the local environment.

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