Results 271 to 280 of about 268,686 (320)
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Nuclear magnetic resonance imaging in the solid state
Progress in Nuclear Magnetic Resonance Spectroscopy, 1991During the last two decades much research effort has been invested in the development of techniques for nuclear magnetic resonance (NMR) imaging. Because of the difficulties associated with imaging of solids, the majority of the research carried out to date has been directed towards the liquid state, and applications have been principally directed to ...
P. Jezzard +3 more
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NUCLEAR MAGNETIC RESONANCE SPECTROSCOPY TECHNIQUES | Solid-State
2005As in NMR of liquid samples, solid state NMR probes the magnetic interactions of atomic nuclei. These interactions yield detailed information about the local structure and dynamics of the sample, including the bonding types and geometry, the site-site connectivity patterns, and the spatial characteristics and time-scales of atomic and molecular motions.
Zwanziger, J., Spiess, H.
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The first solid-state 171Yb nuclear magnetic resonance spectra
Solid State Nuclear Magnetic Resonance, 1994The first powder and magic-angle spinning (MAS) experiments on 171Yb are reported. The divalent ytterbium compound RbYbI3 was studied by solid-state 171Yb nuclear magnetic resonance (NMR) and a powder spectrum of axial symmetry was obtained. The principal components of the chemical shielding tensor were determined as sigma 11 = sigma 22 = -62 ppm and ...
X A, Mao, X, Zhao, C, Ye, S, Wang
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Solid-State Nuclear Magnetic Resonance Spectroscopy-Pharmaceutical Applications
Journal of Pharmaceutical Sciences, 2003Solid-state nuclear magnetic resonance (NMR) spectroscopy has become an integral technique in the field of pharmaceutical sciences. This review focuses on the use of solid-state NMR techniques for the characterization of pharmaceutical solids (drug substance and dosage form). These techniques include methods for (1) studying structure and conformation,
Patrick A, Tishmack +2 more
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Solid-state nuclear magnetic resonance in the rotating tilted frame
The Journal of Chemical Physics, 2008Recent methodological advances have made it possible to measure fine structure on the order of a few hertz in the nuclear magnetic resonance (NMR) spectra of quadrupolar nuclei in polycrystalline samples. Since quadrupolar couplings are often a significant fraction of the Zeeman coupling, a complete analysis of such experimental spectra requires a ...
Nicole M, Trease, Philip J, Grandinetti
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Solid-State Nuclear Magnetic Resonance Spectroscopy of Minerals
Annual Review of Earth and Planetary Sciences, 1985Nuclear magnetic resonance (NMR) spectroscopy has been a useful tool for examining the structure of molecules in solution since the 1950s. It has only been since the late 1970s and early 1980s, though, that developments in very high field superconducting magnets and magic-angle sample-spinning (MASS) have made NMR routinely useful for examining the ...
R. James Kirkpatrick +4 more
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Solid-State Emulsions: Evaluation by 1H and 13C Solid-State Nuclear Magnetic Resonance
Pharmaceutical Research, 1994The molecular environment of sucrose and mineral oil within sucrose and mineral oil solid state emulsions was investigated by NMR techniques. The 13C and 1H chemical shifts of sucrose and mineral oil to those observed in solid state emulsions (comprised of sucrose and mineral oil) were equivalent, indicating that the local structure of sucrose is ...
M L, Shively, S F, Dec
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Solid State Nuclear Magnetic Resonance Spectroscopy
1993The area of mesoporous materials tends to suffer from a lack of detailed structural analysis, that is due to a dearth of well crystallisad materials and ill-defined pore size. That is to say that the crystals produced are often 100 small to diffract X-rays coherently, let alone large and sufficiently free of defects for single crystal X-Ray analysis to
M. J. Hudson, A. D. Workman
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Nuclear Magnetic Resonance in Solid‐State Chemistry
Angewandte Chemie International Edition in English, 1972AbstractVarious problems of solid‐state chemistry can be solved by spectroscopic investigation of the nuclear magnetic resonance (NMR and NQR methods). This progress report presents a survey of the nature of the interactions in the crystal that underlie such measurements, of the observations in the spectrum, and of the information obtainable from it ...
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Characterization of pitches by solid state nuclear magnetic resonance
Fuel, 1989Abstract Solid petroleum, ethylene-cracker, and coal tar pitches were characterized by 13C cross-polarizationmagic-angle-spinning nuclear magnetic resonance spectroscopy (CP/MAS n.m.r.) and by dipolar dephasing. The relative numbers of carbon atoms were determined by peak synthesis of the dipolar dephased (DD) spectrum and of the difference spectrum ...
Alan Grint +5 more
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