Patent classifications
G01R33/4831
Nuclear magnetic resonance logging tool having multiple pad-mounted atomic magnetometers
Various disclosed nuclear magnetic resonance (NMR) logging systems and methods employ a plurality of NMR sensors, including atomic magnetometers, mounted on pads. Certain method embodiments include: utilizing the Earth magnetic field to pre-polarize the protons in a formation; utilizing a plurality of atomic magnetometers to obtain NMR measurements; and determining at least one characteristic relaxation time of the formation. The NMR sensor may optionally include a permanent magnet assembly.
Angle adjuster for NMR
An angle adjuster for nuclear magnetic resonance (NMR) includes a linear motion member composed of a shaft and a support member, a rotary member, a conversion mechanism, and a spring. The linear motion member is a member that serves to change, in an NMR probe device, an angle of a sample tube by a linear motion. The rotary member is rotated by a motor. The conversion mechanism converts a rotary motion of the rotary member into a linear motion of the linear motion member. The spring provides, at a portion where the linear motion member and the rotary member are in engagement with each other, a force that urges the linear motion member in one direction toward the rotary member.
B1 field map with contrast medium injection
A method is provided for determining a movement-corrected B1 field map on contrast medium injection, wherein before the injection, a B1 field map is determined. Following the contrast medium administration, a position change is determined at the position at which the B1 field map was determined. With the position change and the B1 field map, the movement-corrected B1 field map is determined.
RAPID SIMULTANEOUS B0 AND B1 MAPPING FOR MAGNETIC RESONANCE IMAGING
A method for acquiring magnetic resonance (MR) data from a subject with a magnetic resonance imaging (MRI) system includes generating a first pre-saturation RF pulse having a first flip angle for each of at least one slice in the subject, generating a series of first gradient echo sequences following each first pre-saturation RF pulse, and calculating a B0 value for each of the at least one slice. A second pre-saturation RF pulse having a second flip angle is generated for each of the at least one slice in the subject, followed by a series of second gradient echo sequences, and a B1 is calculated for each of the at least one slice based on the first gradient echo sequences and the second gradient echo sequences.
Systems and methods for radio frequency (RF) based spatial encoding in magnetic resonance imaging using frequency-modulated RF pulses
Radio frequency (RF) gradient based magnetic resonance imaging (MRI) is provided by establishing a gradient in the RF transmit (B1) field using frequency-modulated RF pulses. A difference between the time-bandwidth product of the frequency-modulated RF pulses can be varied to provide impart different phases to magnetic resonance signals, where these different phases provide phase encoding of the acquired data. The time-bandwidth product difference can be created and varied by changing the pulse duration of one frequency-modulated RF pulse relative to the other while keeping the bandwidth of the pulses constant.