Solid-state nuclear magnetic magic angle spinning

Both of these methods have been used for DOM isolation from major rivers and the surface ocean, and the general characteristics of these fractions of DOM are presented in Table I. The major C functional groups of humic substances and ultrafiltered DOM (UDOM) have been characterized by solid-state, cross-polarization magic angle spinning 13C nuclear magnetic resonance (NMR) spectroscopy. The samples of humic substances that were characterized by NMR spectroscopy were collected from the Amazon River... 

Table 2.10. Solid-state cross-polarization magic angle spinning nuclear magnetic resonance spectroscopic studies of environmental samples.

Zhang, M., and Maciel, G.E. Built-in carbon-13 intensity reference for solid-state analysis by magic-angle-spinning nuclear magnetic resonance spectrometry,... 

Keywords Magic-angle spinning Solid state Nuclear magnetic resonance... 

We present a solid-state nuclear magnetic resonance (NMR) experiment that allows the observation of a high-resolution two-dimensional heteronuclear correlation (2D HETCOR) spectrum between aluminum and phosphorous in aluminophosphate molecular sieve VPI-5. The experiment uses multiple quantum magic angle spinning (MQMAS) spectroscopy to remove the second order quadrupolar broadening in Al nuclei. The magnetization is then transferred to spin-1/2 nuclei of P via cross polarization (CP) to produce for the first time isotropic resolution in both dimensions. 

M.A. Eastman, G.A. Barral, A.J. Pines, Variable-angle correlation spectroscopy in solid-state nuclear magnetic resonance, J. Chem. Phys. 97 (1992) 4800-4808. (d) A-C. Kolbert, R.G. Griffin, Two-dimensional resolution of isotropic and anisotropic chemical shifts in magic angle spinning NMR, Chem. Phys. Lett. 166 (1990) 87—91. 

G. Pileio, Y. Guo, T.N. Pham, .M. Griffin, M.H. Levitt, S.P. Brown, Residual dipolar couphngs by off-magic-angle spinning in solid-state nuclear magnetic resonance spectroscopy, . Am. Chem. Soc. 129 (2007) 10972—10973. 

Comparable starch-based materials with an amylose content close to zero, even in the presence of complexing agents, do not show any peak at 947 cm. The V-type structure formation can also be detected using X-ray diffraction analysis and cross-polarisation magic angle spinning solid-state nuclear magnetic resonance [122-125]. 

H.G. Brittain, unpublished results for solid-state nuclear magnetic resonance spectra obtained at a frequency of 270 MHz, using a combination of magic-angle spinning and cross-polarization. The spectra were obtained using a contact time of 1 millisecond and a 3 second recycle time. 

Figure 9 (A) Typical line shape of an observed quadrupolar nucleus S, showing the second-order quadrupole shift AcTqs, and the relative position of the centre-of-gravity with respect to the isotropic chemical shift ajso- (B) Al solid-state MAS NMR spectrum of Sr8(AI02)i2-Se2 at 78.15 MHz (7.05 T). Asterisks denote sidebands. Reproduced with permission of Elsevier Science Publishers from Weller MT, Brenchley ME, Apperley DC and Davies NA (1994) Correlations between aI magic-angle spinning nuclear magnetic resonance spectra and the coordination geometry of framework alumlnates. Solid State Nuclear Magnetic Resonance Z 103-106.

G. De Paepe, Dipolar Recoupling in Magic Angle Spinning Solid-State Nuclear Magnetic Resonance, Annu. Rev. Phys. Chem., 2012, 63, 661. 

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