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The detection of the NMR signal during or after the RF pulse, due to the voltage induced in a detection coil by precession of the nuclear spins around B 0. After an RF pulse, precession usually occurs with the nuclei's Larmor frequency and, in itself, does not involve transitions between spin states or energy levels. [1]
Free induction decay (FID) nuclear magnetic resonance signal seen from a well shimmed sample. In Fourier transform nuclear magnetic resonance spectroscopy, free induction decay (FID) is the observable nuclear magnetic resonance (NMR) signal generated by non-equilibrium nuclear spin magnetization precessing about the magnetic field (conventionally along z).
The decay of RF-induced NMR spin polarization is characterized in terms of two separate processes, each with their own time constants. One process, called T 1, is responsible for the loss of resonance intensity following pulse excitation. The other process, called T 2, characterizes the width or broadness of resonances.
Thus, the transmitting coil is a good EM near-field generator at radio frequency, but a poor EM radiation transmitter at radio frequency. The receiver coil picks up the oscillations at RF frequencies produced by precession of the magnetic moment of nuclei inside the subject. The signal acquired by the coil is thus an induced emf, and is not the ...
A 900 MHz NMR instrument with a 21.1 T magnet at HWB-NMR, Birmingham, UK. Nuclear magnetic resonance spectroscopy, most commonly known as NMR spectroscopy or magnetic resonance spectroscopy (MRS), is a spectroscopic technique based on re-orientation of atomic nuclei with non-zero nuclear spins in an external magnetic field.
A phenomenological definition of the NOE in nuclear magnetic resonance spectroscopy (NMR) is the change in the integrated intensity (positive or negative) of one NMR resonance that occurs when another is saturated by irradiation with an RF field. The change in resonance intensity of a nucleus is a consequence of the nucleus being close in space ...
In this sequence, several 180 refocusing radio-frequency pulses are delivered during each echo time (TR) interval, and the phase-encoding gradient is briefly switched on between echoes. [13] The FSE/TSE pulse sequence superficially resembles a conventional spin-echo (CSE) sequence in that it uses a series of 180º-refocusing pulses after a ...
Solid-state 900 MHz (21.1 T [1]) NMR spectrometer at the Canadian National Ultrahigh-field NMR Facility for Solids. Solid-state nuclear magnetic resonance (ssNMR) is a spectroscopy technique used to characterize atomic-level structure and dynamics in solid materials. ssNMR spectra are broader due to nuclear spin interactions which can be categorized as dipolar coupling, chemical shielding ...