114results about "Measurements using double resonance" patented technology

An apparatus and method is discussed for characterizing a fluid sample downhole of aliphatic hydrocarbon compounds, aromatic hydrocarbon compound, or connate mud filtrates containing carbon-13 isotopes using an enhanced nuclear magnetic resonance (NMR) signal on a measurement-while-drilling device. To enhance the carbon-13 NMR signal these nuclei are being hyperpolarized. Either the Overhauser Effect (OE) or the Nuclear Overhauser Effect or optical pumping and the Spin Polarization Induced Nuclear Overhauser Effect (SPINOE) can serve as a mechanism for hyperpolarization of the carbon-13 nuclei.

The present invention relates to devices and method for dissolving solid polarised material while retaining a high level of polarisation. In an embodiment of the present invention a material is polarised in a strong magnetic field in a cryostat 2 and then brought into solution while still inside the cryostat 2.

The present invention relates to devices and methods for melting a solid polarised sample while retaining a high level of polarisation. In an embodiment of the present invention a sample is polarised in a sample-retaining cup in a strong magnetic field in a polarising means in a cryostat and then melted inside the cryostat by melting means such as a laser connected by an optical fibre to the interior of the cryostat.

A coolant sub-assembly is provided for use in a DNP apparatus. The sub-assembly comprises a plurality of concentric jackets surrounding an inner bore tube having first and second opposed ends. The jackets are adapted to inhibit heat flow to the inner bore tube, a DNP working region being defined within the inner bore tube where a DNP process will be performed on a sample in the DNP working region. A coolant supply path extends adjacent an outer surface of the inner bore tube at the DNP working region in order to cool said outer surface, whereby a sample holder assembly can be inserted through the first end of the inner bore tube to bring a sample holder into the DNP working region and can be moved through the second end of the inner bore tube. An auxiliary coolant supply path supplies coolant to a sample, located in use in the sample holder at the DNP working region, through at least one aperture in the inner bore tube wall at the DNP working region. One or both ends of the inner bore tube opens into a coolant waste path for conveying coolant away from the inner bore tube, and wherein the coolant, auxiliary coolant, and waste paths are coupled to pumping means in use to cause coolant to pass along the coolant, auxiliary coolant and waste paths.

NMR probe coils designed to operate at two different frequencies, producing a strong and homogenous magnetic field at both the frequencies. This single coil, placed close to the sample, provides a method to optimize the NMR detection sensitivity of two different channels. In addition, the present invention describes a coil that generates a magnetic field that is parallel to the substrate of the coil as opposed to perpendicular as seen in the prior art. The present invention isolates coils from each other even when placed in close proximity to each other. A method to reduce the presence of electric field within the sample region is also considered. Further, the invention describes a method to adjust the radio-frequency tuning and coupling of the MAR probe coils.

An apparatus for DNP-NMR measurement on a sample, with a magnet configuration for producing a magnetic field in a first working volume and in, a second working volume with a magnetic field gradient in the direction of an axis (z) which extends through the second working volume, with a device for measuring MR signals, with a DNP excitation device, and with a positioning mechanism for transferring the sample, is characterized in that, near the second working volume, a compensation configuration made of magnetic material is mounted that, in the operating condition of the magnet configuration, produces a magnetic field gradient in the direction of the axis (z) in the second working volume that is between −90% and −110% of the magnetic field gradient of the same order of the stray field of the magnet configuration.