Wide Line Nuclear Magnetic

The indirect procedures are used primarily for measurement of lipids without isolation. The application of wide-line nuclear magnetic... 

Mills, B.L. and van der Voort, F.R. 1981. Comparison of the direct and indirect wide-line nuclear magnetic resonance methods for determining solid fat content. J. Am. Oil Chem. Soc. 58 776-778. 

The solid fat content of an oil is a measure (in percent) of the amount of solid fat present in the oil at any one temperature. It is measured by means of wide-line nuclear magnetic resonance (NMR) spectrometry after a standard tempering procedure for the samples. 

Haughton, A.J., K. VanPutte, and L.F. Vermas, Determination of the Solid Content of Fats by Wide Line Nuclear Magnetic Resonance The Signal of Liquid Oils, Ibid. 49 153-156(1972). 

Mills, B.L., and F.R. VanDeVoort, Comparison of the Direct and Indirect Wide Line Nuclear Magnetic Resonance Methods for Determining Solid Fat Content, Ibid. 58 776-778 (1981). 

Ferken, W.P., and R.E. Morse, Wide-Line Nuclear Magnetic Resonance of Liquid/Solid Content of Soybean Oil at Various Degrees of Hydrogenation, Food Technol. 17 1099-1068 (1963),... 

Robinson, J.W., Ed. Handbook of Spectroscopy CRC Press Boca Raton, FL, 1974, Vol. II. Rodgers, J.E. Wide line nuclear magnetic resonance in measurement of finish-on-fiber of textile products. Spectroscopy 1994, 9(8), 40. 

In industry, most lipid analysts are familiar with wide-line nuclear magnetic resonance (NMR). In Chapter 4 Diehl describes the application of Fourier transform NMR spectroscopy and illustrates that the technique can be used in lipid chemistry both qualitatively and quantitatively. By means of... 

Of spectroscopic teclmiques, nuclear magnetic resonance (NMR) has been most widely used to measure orientational ordering in liquid crystals [M, 57 and ]. Most commonly, changes of line splittings in the spectra of... 

The wide line fluorine nuclear magnetic resonance of the intercalation compound "CifcBFV may be used not only to demonstrate the chemical identity of the inserted species but also to establish the translational freedom of this species. The chemical shift of the fluorine resonance is at (70+10) ppm vs. CF3COOH, consistent (11) with BF4 (71 ppm) but not with BF3 (54 ppm). (The neutral/ anion complex, B2 7> is also possible (12)). The derivative extremum llnewldth is narrow (0.02 mT = 800 Hz) at all temperatures between -168°C and 23°C. A simple calculation suggests that translation, and not rotation, is the cause of this narrow line. Assuming a first stage compound (as indicated by X-ray diffraction)... 

Nuclear magnetic resonance (NMR) spectroscopy has proved to be a method of considerable interest and importance for the study of polymers, and during the past 10—12 years a large number of investigations of a variety of polymer systems have been published. This work has been ably reviewed by Slighter (7). These studies have dealt with solid polymers and the spectra obtained have been of the so-called broad-band or "wide-line type. In such polymer spectra, as in the... 

Solids give rise to the "wide-line" or (broad-line) spectra, because the local fields arising from nuclear magnetic dipole interactions contribute significantly to the total field experienced by a nucleus in the solid state. A measure of this direct spin-spin interaction is the spin-spin relaxation time T2 (see Sect. 12.2.1.3), which is much shorter in solids than in liquids, and thus gives rise to broader lines (of the order of 10-6 to 10 4 T, depending on the kind of nucleus). Now the contour of the absorption line provides information as to the relative position of the neighbouring nuclei. 

---