chemical shift


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chemical shift

[′kem·i·kəl ′shift]
(physical chemistry)
Shift in a nuclear magnetic-resonance spectrum resulting from diamagnetic shielding of the nuclei by the surrounding electrons.
References in periodicals archive ?
The chemical shift displacements found in the spectra of pyrimethanil/HP-[beta]-CD, when compared with free fungicide (guest), point out the occurrence of a complexation process that can be attributed to the influence of the guest (pyrimethanil) included in CD cavity.
The presence of a hydroxyl group at C-3" was indicated from the chemical shift in the [sup.13]C NMR [[delta].sub.C] 69.7 (C-3") and the HREIMS data.
As was shown in Figure 1, compared with the original PEG (Figure 1(a)), the shift of 2.86 ppm (peak b) which appears in Figure 1(b) is the chemical shift of methylene protons which linked with amino group.
Detecting and manipulating these signals with a computer provides a graph of frequency, sometimes called a chemical shift, versus intensity, forming a characteristic series of peaks--the classic NMR spectrum.
Chemical shift imaging is the principal technique employed in the MR evaluation of adrenal lesions using in-and out-of-phase techniques, and exploits the presence of abundant intracellular lipid in adenomas that helps to distinguish them from non-adenomatous lesions.
(2008) compiled a heteronuclear single quantum coherence-based metabolite chemical shift database that contains only NMR spectra of standard compounds measured under standardized conditions.
The change in the chemical shift upon halogen bonding was found to be the greatest on the alpha fluorine signals.
In addition, the PPAR[alpha]LBD binding interface on L-FABP is mapped using NMR chemical shift perturbation experiments.
where [zeta]H is the chemical shift of the protons on saturated carbon to be calculated; A is a constant with the values of 0.87, 1.20, and 1.55 for methyl, methylene.
Imaging studies can distinguish encapsulated fat (progressive nodular lipomatosis and multiple hereditary lipomas, hibernoma) from Madelung disease by means of fat suppression and chemical shift imaging.