摘要:
The magnetized structure that induces in a central area of interest a homogeneous magnetic field oriented along a longitudinal axis (z) of the structure comprises first and second magnetized rings (111, 121) disposed symmetrically relative to a plane (P) that is perpendicular to said longitudinal axis (z) and that contains said central area of interest, and one median annular magnetized structure (330) disposed between the first and second magnetized rings (111, 121) and also disposed symmetrically relative to the plane (P) of symmetry. The first magnetized ring (111) is magnetized radially relative to the longitudinal axis (z) with divergent magnetization, the second magnetized ring (121) is magnetized radially relative to the longitudinal axis (z) with convergent magnetization, and the median annular magnetized structure (330) is magnetized along the longitudinal axis (z). The median annular magnetized structure (330) is divided into at least two slices (331A, 331B, 332A, 332B) along the longitudinal axis (z) and the first and second magnetized rings (111, 121) and the various slices (331A, 331B, 332A, 332B) of the median magnetized structure (130) are each divided into identical components in the form of regularly distributed sectors.
摘要:
A new two-dimensional NMR carbon-proton chemical shift correlation experiment, the MAS-J-HMQC experiment, is proposed for rotating solids. The magnetization transfer used to obtain the correlations is based on scalar heteronuclear J couplings. The 2D map provides through-bond chemical shift correlations between directly bonded proton carbon pairs in a similar way to corresponding high-resolution liquid state experiments. The transfer through J coupling is shown to be efficient and more selective that those based on heteronuclear dipolar couplings. The experiment, which works at high MAS spinning rates, yields the unambiguous assignment of the proton resonances. The experiment is demonstrated on several organic compounds.
摘要:
A magnetized structure that induces in a central area of interest a homogeneous magnetic field of predetermined orientation relative to a longitudinal axis (z) of the structure comprises at least two magnetized rings (110, 120) disposed symmetrically relative to a plane (P) that is perpendicular to the longitudinal axis (z) and that contains the central area of interest, and at least one median annular magnetized structure disposed at least partly between the two magnetized rings (110, 120) and also disposed symmetrically relative to the plane (P) of symmetry, one of the two magnetized rings (110) being magnetized radially relative to the longitudinal axis (z) with divergent magnetization and the other of the two magnetized rings (120) being magnetized radially relative to the longitudinal axis (z) with convergent magnetization, and the median annular magnetized structure being magnetized with an orientation different from that of the magnetization of the two magnetized rings (110, 120). The median annular magnetized structure comprises at least one magnetized ring (150) having a magnetization distribution of orientation that varies as in Halbach dipoles and the first two magnetized rings (110, 120) and the median annular magnetized structure are each divided into individual components in the form of regularly distributed identical sectors.
摘要:
The magnetized structure that induces in a central area of interest a homogeneous magnetic field oriented along a longitudinal axis (z) of the structure comprises first and second magnetized rings (111, 121) disposed symmetrically relative to a plane (P) that is perpendicular to said longitudinal axis (z) and that contains said central area of interest, and one median annular magnetized structure (330) disposed between the first and second magnetized rings (111, 121) and also disposed symmetrically relative to the plane (P) of symmetry. The first magnetized ring (111) is magnetized radially relative to the longitudinal axis (z) with divergent magnetization, the second magnetized ring (121) is magnetized radially relative to the longitudinal axis (z) with convergent magnetization, and the median annular magnetized structure (330) is magnetized along the longitudinal axis (z). The median annular magnetized structure (330) is divided into at least two slices (331A, 331B, 332A, 332B) along the longitudinal axis (z) and the first and second magnetized rings (111, 121) and the various slices (331A, 331B, 332A, 332B) of the median magnetized structure (130) are each divided into identical components in the form of regularly distributed sectors.
摘要:
The present invention concerns an apparatus (1′) for NMR spectroscopy and/or NMR imaging of a sample. The apparatus comprises a static probe comprising an outer coil for excitation of nuclei of said sample by generating an incident radio frequency field at the Larmor frequency of said nuclei, and for reception of a return radio frequency field emitted by said sample, and a sensitive inner coil (6a′) which is mounted closely around or in contact with the sample container and which is wirelessly coupled to said outer coil by an electromagnetic radio frequency field. The sensitive inner coil is embedded in an inner spinning rotor (2) which is rotatively mounted inside said static probe and which is integral with said sample container, so that the filling factor and the radio frequency field amplitude in said sensitive coil are maximized.