chemical shift


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chem·i·cal shift

dependence of the resonance frequency of a nucleus on the chemical binding of the atom or molecule in which it is contained. See: chemical shift artifact.

chemical shift

(in nuclear magnetic resonance spectrometry) the position of a resonance in the substance of interest relative to the position of the resonance of a standard. Nonequivalent atoms of a molecule have different chemical shifts.

chemical shift

An MRI term for a variation in the nominal Larmor frequency for a particular isotope within the imaging volume. The amount of chemical shift is directly proportional to the strength of the magnetic field, and is specified in parts per million of the resonant frequency.
References in periodicals archive ?
Assigning stereodiversity of the 27-Me group of furostane-type steroidal saponins via NMR chemical shifts.
Benign adrenocortical masses: Diagnosis with chemical shift MR imaging.
66 ppm chemical shift, representing lactate and ethanol respectively, were observed in the co-cultures.
The accuracy of soft tissue dimensional measurement can be affected by chemical shift resulting from fat and adipose tissue.
Table 2: Protonational chemical shift increments [DELTA][delta] of C([beta])H-C([alpha]) caused by a substituent group Substituent groups and [DELTA][delta] their position in [alpha] substituent group [CH.
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.
Each peak was defined by three parameters: the chemical shift (frequency), intensity, and line width.
It is clear that the chemical shift for the ortho-HM group depends on the alkali content (Figs 1 and 2).
They showed that the anumeric proton for [alpha]-naphthol glucoside has a chemical shift of [[delta].
The spectra of original and ionoactivated ash samples exhibit broad resonance in the chemical shift range from -80 to -110 ppm.
In NMR spectroscopy, one often measures the chemical shift, which specifies the fractional change in the resonant frequency for different chemical species and is typically on the order of a few parts per million.
Maybe there is a chemical shift the moment they are assigned an office in the Capitol building that affects their perspective and judgment.