Integrators, NMR

Initiation step (radical), 140 Insulin, structure of, 1035 Integration (NMR), 459 Intermediate, See Reaction intermediate lntoxilyzer test, 637 Intramolecular aldol reaction,... 

Extrapolating from the low-temperature integrated NMR spectra provides an independent measure of the equilibrium constant within the temperature range at which line shape analysis is carried out. This simplifies the line shape analysis to just one dynamic parameter, say kr, since k = Kkx. 

The sodium-23 MASNMR spectra of the Y zeolite samples with these particular levels of cation exchange are shown in Figure 2, along with the spectrum of the Na-Y zeolite. Simulations of these spectra indicate that about 25, 10, and 20% of the integrated NMR intensity of the respective exchanged zeolites arises from residual Na cations in the supercages. The different Na NMR lines are best resolved in the case of the (NH, Na)-Y zeolites. 

We are now working on further extensions and refinements of the computer programs integrating NMR and MS data. One promising possibility is the elimination of the uncertainty by 13C NMR between alpha to aromatic and junction carbon atoms by using values calculated by MS for the latter. Work in this area will be reported in further communications. 

Problem 13.21 I The integrated NMR spectrum of a compound of formula C4HjqO is shown in... 

Guerrini M, Raman R, Venkataraman G, Torri G, Sasisekharan R, Casu B. A novel computational approach to integrate NMR spectroscopy and capillary electrophoresis for strucsture assignment of heparin and heparan sulfate oligosaccharides. Glycobiology 2002 12 713-719. 

Figure 5. Total integrated NMR line intensity of the hydrated, partially calcium and ammonium exchanged Na-Y zeolites versus the percent of cation exchange.

Figure 6. Integrated NMR line intensities of the component NMR lines of the hydrated, partially ammonium exchanged Na-Y zeolite series normalized by the total integrated NMR line intensities given in Figure 5.

At the University of Twente in the Netherlands, a multichannel chip has been designed with an integrated NMR detection coil and has yielded promising results at low field... 

Kongsted J, Mennucd B. How to model solvent effects on molecular properties using quantum chemistry Insights from polarizable discrete or continuum solvation models. JPhys Chem A. 2007 lll(39) 9890-9900. http //dx.doi.org/10.1021/jp074343w. Marini A, Macchi SJurinovich S, Catalano D, Mennucd B. Integrated NMR. and computational smdy of push-pull NLO probes interplay of solvent and stractural effects. J Phys Chem A. 2011 115(35) 10035—10044. http //dx.doi.org/10.1021/jp203864a. 

J. M. Perez and C. Kaittanis, An Integrated NMR/Nanosensor System for Sensitive Detection of Environmental Toxins and Harmful Microbes , in NSTI Nanotech 2007, Nanotechnology Conference and Trade Show, Santa Clara, CA, United States, May 20-24, 2007, eds. M. Laudon and B. Romanowicz, CRC Press, Boca Raton, Fla., 2007, vol. 2, p. 663. 

Example A compound of molecular formula C9H10O2 gives the following integrated NMR spectrum. How many protons give rise to each signal ... 

Paze, C., Zecchina, A., Spera, S., Spano, G., and Rivetti, F. Acetonitrile as probe molecule for an integrated NMR and FTIR study of zeobtic Br0nsted acidity interaction with zeolites H-feirierite and H-beta. Pl s. Chem. Chem. Phys. 2000, 2, 5756-5760. 

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