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Thallium chemical shift referencing
Journal of Magnetic Resonance, 2021Thallium chemical shifts are very sensitive to chemical and physical conditions. This makes accurate chemical shift referencing difficult. Therefore, chemical shifts are usually referenced to the 1H reference multiplied by a standard factor. However, past papers are referenced to TlNO3 solution in water at infinite dilution. The chemical shift of TlNO3
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Narrowband chemical-shift imaging
Applied Optics, 1985In this paper we introduce an efficient method for NMR chemical shift imaging which is especially well suited for imaging proton chemical shifts. With realistic observation times and pulse sequences, one is operating close to the theoretical limits of this method.
E, Feig, F, Greenleaf
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Chemical shift anisotropy amplification
Journal of Magnetic Resonance, 2004A new NMR experiment which allows a measurement of the chemical shift anisotropy (CSA) tensor under magic angle spinning (MAS) is described. This correlates a fast MAS spectrum in the omega2 dimension with a sideband pattern in omega1 in which the intensities mimic those for a sample spinning at a fraction of the rate omega r/N, and these sidebands ...
Shao LM +4 more
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SPIE Proceedings, 1986
Until the 1980s the main use of nuclear magnetic resonance has been as a chemical analytical technique. The sample was homogenous, usually being a solution of the material of interest in a suitable solvent. The end product was a high resolution spectrum, i.e., one containing many narrow lines exhibiting chemical shift and coupling constant effects, and
Paul M. G. Margosian +4 more
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Until the 1980s the main use of nuclear magnetic resonance has been as a chemical analytical technique. The sample was homogenous, usually being a solution of the material of interest in a suitable solvent. The end product was a high resolution spectrum, i.e., one containing many narrow lines exhibiting chemical shift and coupling constant effects, and
Paul M. G. Margosian +4 more
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Chemical-Shift-Chemical - Shift Correlation Spectroscopy in Powdered Solids
Journal of Magnetic Resonance, Series A, 1993Abstract Sample reorientation during the mixing time of a two-dimensional NMR exchange experiment allows the measurement of chemical-shift tensors in powdered samples whose one-dimensional powder patterns are too complex to reliably analyze. This technique has the advantages that the chemical-shift anisotropy has an unscaled representation, the ...
C.D. Hughes +3 more
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Comparison of AES chemical shifts with XPS chemical shifts
Applied Surface Science, 1996Abstract Scanning Auger microprobe equipped with a concentric hemispherical analyzer allows us to measure AES spectra with high-energy resolution. The question is the extent of chemical state information obtainable by AES. XPS chemical shifts and AES chemical shifts, derived from transition energies available from literature, have been compared for ...
Tetsu Sekine +2 more
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Tetrahedron, 1967
Abstract The McDonnel equation has been modified to include those cases where the distance between the shielding group and the proton observed is small compared to the length of the induced dipole. The principle has been established that in calculating the chemical shift produced by the introduction of a substituent into a molecule, the screening ...
J.W. ApSimon +5 more
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Abstract The McDonnel equation has been modified to include those cases where the distance between the shielding group and the proton observed is small compared to the length of the induced dipole. The principle has been established that in calculating the chemical shift produced by the introduction of a substituent into a molecule, the screening ...
J.W. ApSimon +5 more
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2015
This chapter discusses chemical shifts. These give information on molecular identity and structure. The nuclear magnetic resonance (NMR) frequency of a nucleus in a molecule is determined principally by its magnetogyric ratio and the strength of the magnetic field it experiences. Chemical shifts arise because the field actually experienced by a nucleus
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This chapter discusses chemical shifts. These give information on molecular identity and structure. The nuclear magnetic resonance (NMR) frequency of a nucleus in a molecule is determined principally by its magnetogyric ratio and the strength of the magnetic field it experiences. Chemical shifts arise because the field actually experienced by a nucleus
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The Journal of Chemical Physics, 1969
The phase-alternated experiment in liquids, a multiple-pulse NMR experiment capable of scaling chemical shifts, is examined theoretically and experimentally. The theory of the experiment is worked out using both the average-Hamiltonian and classical magnetic-dipole techniques, and the results from the two methods are compared.
J. D. Ellett, J. S. Waugh
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The phase-alternated experiment in liquids, a multiple-pulse NMR experiment capable of scaling chemical shifts, is examined theoretically and experimentally. The theory of the experiment is worked out using both the average-Hamiltonian and classical magnetic-dipole techniques, and the results from the two methods are compared.
J. D. Ellett, J. S. Waugh
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Empirical isotropic chemical shift surfaces
Journal of Biomolecular NMR, 2007A list of proteins is given for which spatial structures, with a resolution better than 2.5 A, are known from entries in the Protein Data Bank (PDB) and isotropic chemical shift (ICS) values are known from the RefDB database related to the Biological Magnetic Resonance Bank (BMRB) database.
Eszter, Czinki, Attila G, Császár
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