Nuclear magnetic resonance spectrometry

In Chapter 1, we have studied the effect of nuclear magnetic resonance (NMR) [69-78]. In this section, we study NMR spectrometry and consider some applications of NMR in materials science. 

A further method for distinguishing between different types of hydroxy groups in polymers is the NMR method described by L Ho [14]. This procedure is based on the reaction of the hydroxy compound with hexafluoroacetone to form the adduct shown below which is amenable to F-NMR spectroscopy  

Based on an average molecular weight of 1010 Based on an average molecular weight of 4000 Polyepichlorihydrin 2000 from Shell Chemical Co.  

Reprinted with permission from F.F-L. Ho, Analytical Chemistry, 1973, 45, 3, 603. 1973, American Chemical Society [14]  

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Pullen, F. S., Swanson, A. G., Newman, M. J. and Richards, D. S., On-line liquid chromatography/nuclear magnetic resonance spectrometry — a powerful spectroscopic tool for the analysis of mixtures of pharmaceutical interest, Rapid Comm. Mass. Spectr., 9, 1003, 1995. 

Fourier Transform Mass Spectrometry Fourier Transform Nuclear Magnetic Resonance Spectrometry... 

Both absorption and emission may be observed in each region of the spectrum, but in practice only absorption spectra are studied extensively. Three techniques are important for analytical purposes visible and ultraviolet spectrometry (electronic), infrared spectrometry (vibrational) and nuclear magnetic resonance spectrometry (nuclear spin). The characteristic spectra associated with each of these techniques differ appreciably in their complexity and intensity. Changes in electronic energy are accompanied by simultaneous transitions between vibrational and rotational levels and result in broadband spectra. Vibrational spectra have somewhat broadened bands because of simultaneous changes in rotational energy, whilst nuclear magnetic resonance spectra are characterized by narrow bands. 

Nuclear magnetic resonance spectrometry has been used to quantitate aspirin in a combination product with a coefficient of variation of 1.1.102 For quantitation, the shift at 2.3 ppm representing the ester methyl group was used. 

Using circular dichroism and nuclear magnetic resonance spectrometry, Veatch and coworkers1 established that four conformational species of gramicidin A exist in solution. Two were postulated to be helixes of opposite handedness. 

The second basic approach to characterizing seawater DOM is to concentrate a fraction of the total mixture by chemical or physical means into either dry powder or concentrated solution. The solution can be analyzed using a wide array of methods (e.g., elemental analysis, biomarker analysis, mass, or nuclear magnetic resonance spectrometry) to which these isolates are amenable. 

The isolated 1-indanol was collected and 1 L of the solution was submitted for GC-MS analysis, as described above, and the compound identity was confirmed by nuclear magnetic resonance spectrometry. ... 

Gilpin, R.K. and Gangoda, M.E., Nuclear magnetic resonance spectrometry of alkyl ligands immobilized on reversed phase liquid chromatographic surfaces, Anal. Chem., 56, 1470, 1984. 

Nuclear magnetic resonance spectrometry. iH-nuclear magnetic resonance (NMR) spectra of samples in deuterium oxide were run at 500 MHz (IV and V-2) with a Bruker AMX-500 and at 300 MHz (V-2 and D,L-hydrox-ylysine) with a Gemini-300 (Varian) with the HOD signal at 8 4.8 ppm. 

A. Nordon, C. Meunier, R.H. Carr, P.J. Gemperline, and D. Littlejohn, Determination of the ethylene oxide content of polyether polyols by low-field H nuclear magnetic resonance spectrometry. Anal. Chim. Acta, 472, 133-140... 

GC = gas chromatography, Py = pyrolysis (flash or hydrous heating), MS = mass spectrometry (HR = high resolution), IRMS = isotope ratio mass spectrometry, HPLC = high-pressure liquid chromatography, EC = electron capture. Cl = chemical ionization, NMR = nuclear magnetic resonance spectrometry. X-ray = X-ray crystallography. 

Fulvic and humic acids have been investigated with carbon-13 and proton nuclear magnetic resonance spectrometry, GC/MS, and IR spectroscopy. The fulvic and humic acids were found to be predominantly carboxylic and aromatic with a high proportion of 0- and Ji-substituted carbon atoms, although aliphatic ones were also observed. 

Four kauranes present in the petroleum ether/ethyl acetate fractions of nemoralis were fully characterized by mass spectrometry, nuclear magnetic resonance spectrometry and infrared as (-)-kaur-16-en-19-oic acid, (-)-kauran-16 <-ol, 15sC-hydroxy-(-)-kaur-16-en-19-oic acid and 17-hydroxy-(-)-kaur-15-en-19-oic acid... 

M.C. Malet-Martino, J.P. Armand, A. Lopez, J. Bernadou, J.P. Beteille, M. Bon, R. Martino, Evidence for the importance of 5 -deoxy-5-fluorouridine catabolism in humans from F nuclear magnetic resonance spectrometry. Cancer Res. 46 (1986) 2105-2112. 

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