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A portion of this database is still available in a three volume print version from Aldrich. The full electronic version includes a supplement of spectra not included in the paper version. In all, this database includes more than 15,000 compounds with the associated 300 MHz 1 H and 75 MHz 13 C spectra. The product includes the software necessary ...
An MRI pulse sequence in magnetic resonance imaging (MRI) is a particular setting of pulse sequences and pulsed field gradients, resulting in a particular image appearance. [ 1 ] A multiparametric MRI is a combination of two or more sequences, and/or including other specialized MRI configurations such as spectroscopy .
Nitrogen-15 nuclear magnetic resonance spectroscopy (nitrogen-15 NMR spectroscopy, or just simply 15 N NMR) is a version of nuclear magnetic resonance spectroscopy that examines samples containing the 15 N nucleus. [1] [2] 15 N NMR differs in several ways from the more common 13 C and 1 H NMR. To circumvent the difficulties associated with ...
Adiabatic full-passage (AFP) pulses are off-resonance-insensitive for a certain bandwidth. Sweep diagrams for two off-resonances are shown in red. In the left plot, the off-resonance magnetization will be inverted by the end of the AFP pulse. In the right plot, the off-resonance magnetization will not be inverted by the end of the AFP pulse.
The Rabi frequency is a semiclassical concept since it treats the atom as an object with quantized energy levels and the electromagnetic field as a continuous wave. In the context of a nuclear magnetic resonance experiment, the Rabi frequency is the nutation frequency of a sample's net nuclear magnetization vector about a radio-frequency field.
Chemical shift δ is usually expressed in parts per million (ppm) by frequency, because it is calculated from [5] =, where ν sample is the absolute resonance frequency of the sample, and ν ref is the absolute resonance frequency of a standard reference compound, measured in the same applied magnetic field B 0.
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).
A sample being investigated using NMR spectroscopy in a zero-field NMR setup. [1]Zero- to ultralow-field (ZULF) NMR is the acquisition of nuclear magnetic resonance (NMR) spectra of chemicals with magnetically active nuclei (spins 1/2 and greater) in an environment carefully screened from magnetic fields (including from the Earth's field).