摘要:
Provided are systems, methods, and apparatus for using nuclear magnetic resonance (NMR) to detect a first material in the presence of a second material within a region of the Earth and within a static magnetic field (such as Earth's magnetic field). These inventions are uniquely suited to detect NMR signals from materials remotely located from a measurement device (e.g., below ice with the device above the ice). They are further useful in detecting first material having relatively short spin-lattice (T1) relaxation time in the presence of second material having longer T1 relaxation time (and therefore slower response to applied magnetic fields). Two pre-polarization currents are used to create pre-polarization magnetic fields stronger than the static magnetic field, each applied over a period of time between the first material's T1 relaxation time and the second material's T1 relaxation time, enabling different ways to null the NMR signal from the second material.
摘要:
Methods and systems for detecting a material within a region of the Earth are provided. The region may be under a surface of earthen formation, ice, snow, or water. The method may be practiced in a variety of applications, for example in an arctic region to detect oil spills, leaks, or seepages. The methods and systems may include using at least one coil to transmit a radio frequency (RF) excitation signal into the region of the Earth; and receive any NMR response signals to determine the presence of the material of interest.
摘要:
Methods and systems for detecting a material within a region of the Earth are provided. The region may be under a surface of earthen formation, ice, snow, or water. The method may be practiced in a variety of applications, for example in an arctic region to detect oil spills, leaks, or seepages. The methods and systems may include using at least one coil to transmit a radio frequency (RF) excitation signal into the region of the Earth; and receive any NMR response signals to determine the presence of the material of interest.
摘要:
There is disclosed a flat NMR (nuclear magnetic resonance) coil system especially adapted for evaluating thin samples of material(s), or samples in which a thin surface region of the sample is to be examined. The apparatus and method work well in a static magnetic field oriented generally perpendicular to the planes of the flat sample and coil. In one preferred mode, the coil is located approximately parallel to (and generally proximate to or in flush contact with) the surface of the subject sample, while the coil typically also is oriented so that the flux of the strong static field for performing the NMR is approximately normal to the planes of the coil and the sample surface. The coil has a wire path routed to define at least one continuous “figure eight” double loop arrangement, to improve operational performance of the complete coil.
摘要:
The present invention provides microcoil magnetic resonance based modules, detection devices, and methods for their use. In certain embodiments, the invention provides a module including a microcoil possessing an inner diameter of between 25 microns and 550 microns, a conduit disposed proximate to the microcoil, in which the conduit is in fluid communication with a sample reservoir, an affinity column in fluid communication with the conduit and the sample reservoir, and a connector for connecting the module to a magnetic resonance detector.
摘要:
A unilateral magnet apparatus having a remote uniform field region. The apparatus' uniform remote field region is suitable for a variety of nuclear magnetic resonance applications.
摘要:
A unilateral magnet apparatus having a remote uniform field region. The apparatus' uniform remote field region is suitable for a variety of nuclear magnetic resonance applications.
摘要:
An apparatus for unilaterally producing a substantially homogeneous magnetic field. The apparatus includes two circular electromagnet coils, a small coil and a large coil, which are coaxial with one another and which are separated by a distance equal to one-half the difference in the radius of the two coils. By appropriate selection of electrical currents, which are passed through the coil in opposite directions, a region of homogeneous magnetic field is formed. This region is centered on the common axis of the two coils, at a point on the axis which is at a distance from the small coil equal to one-half the radius of the small coil, and which is on the opposite side of the small coil from the large coil. The apparatus has particular application in the field of diagnostic medical NMR and other NMR applications.