108 results about "Magnetization transfer" patented technology

A magnetic element includes a channel layer, a first magnetic electrode which is in contact with the channel layer, a second magnetic electrode which is in contact with the channel layer and is insulated from the first magnetic electrode, a first intermediate layer which is provided adjacent to the first magnetic electrode and has a first insulating layer, a first magnetic layer which is provided in contact with a surface of the first intermediate layer on an opposite side to a surface contacting the first magnetic electrode to transfer magnetization to the first magnetic electrode, a first electrode which is connected to the first magnetic electrode, and a second electrode which is connected to the second magnetic electrode, at least one of the first electrode and the second electrode outputting a first signal which changes depending on a magnetic arrangement of the first magnetic electrode and the second magnetic electrode.

An RF coil assembly for an MRI system includes a resonator formed by a cylindrical shield and pairs of opposing conductive legs disposed symmetrically around a central axis and extending the axial length of the shield. One set of conductive leg pairs is tuned to operate at the Larmor frequency of 13C and another set is tuned to operate at the Larmor frequency of 1H. Drive circuitry operates the RF coil assembly to produce 1H spin magnetization which is transferred to 13C magnetization by the nuclear overhauser effect and to acquire MR data from the 13C spins. Multinuclear measurements can be made simultaneously at different Larmor frequencies.

A magnetic element includes a channel layer, a first magnetic electrode which is in contact with the channel layer, a second magnetic electrode which is in contact with the channel layer and is insulated from the first magnetic electrode, a first intermediate layer which is provided adjacent to the first magnetic electrode and has a first insulating layer, a first magnetic layer which is provided in contact with a surface of the first intermediate layer on an opposite side to a surface contacting the first magnetic electrode to transfer magnetization to the first magnetic electrode, a first electrode which is connected to the first magnetic electrode, and a second electrode which is connected to the second magnetic electrode, at least one of the first electrode and the second electrode outputting a first signal which changes depending on a magnetic arrangement of the first magnetic electrode and the second magnetic electrode.

A memory in which thermal stability is improved without increasing the writing current. The memory is provided with a storage element (3) having a storage layer (17) for holding information by the magnetization state of a magnetic body. A magnetization fixation layer (31) is provided on the storage layer (17) through an intermediate layer (16). The intermediate layer (16) consists of an insulator. Direction of magnetization M1 of the storage layer (17) is changed by injecting electrons subjected to spin polarization in the laminating direction, and information is recorded on the storage layer (17). Strain is applied to the storage layer (17)from an insulation layer on the periphery of the storage layer (17) having a smaller coefficient of thermal expansion as compared with the storage layer (17). The memory is also provided with wiring for supplying a current in the laminating direction of the storage element (3).

A pulse sequence for time-of-flight (TOF) magnetic resonance angiography (MRA) includes a fatsat segment, a magnetization transfer segment, and a spatial saturation segment that are applied by an MR apparatus to acquire MR data for image reconstruction with improved image quality. The pulse sequence is constructed such that at the beginning of each iteration of the inner loop of a 3D acquisition, a fatsat pulse is applied. After the fatsat pulse, MR data is acquired in a series of imaging segments with well-suppressed fat signal. Effective fat suppression is achieved by sampling central k-space data first, before signal from fat relaxes back to a pre-saturation level. Each imaging segment is immediately preceded by one of a MT pulse or a spatial saturation pulse and immediately followed by the other one of the MT pulse or the spatial saturation pulse.

An embodiment in accordance with the present invention provides a method for obtaining a magnetic resonance image (MRI) or spectrum. The method includes a step of performing a chemical exchange saturation transfer (CEST) or magnetization transfer (MT) magnetic labeling experiment of a subject using an MRI machine. When performing the CEST or MT magnetic labeling experiment aspects of a saturation pulse or a serial saturation pulse sequence, such as length (tsat), number (Nsat), offset (Δω), modulation frequency (ωs) and power (B1) can be varied in specific-designed schemes. Data is generated from the CEST magnetic labeling experiment and is transmitted to a data processing unit. The data is processed to generate a visual representation of the data.

Apparatus and methods for quantification of transverse relaxation times (T2) using steady-state free precession sequences (generally known as fast imaging sequences) and their sensitivity to a quadratic increase of the RF pulse phase, also known as RF spoiling. Using at least two image acquisitions with different partial RF spoiling increments, T2 can be assessed with high precision and with short acquisition times in the limit of large excitation angles being independent on the longitudinal relaxation time (T1) and magnetization transfer effects as compared to other SSFP based quantitative T2 methods. This invention is not restricted to any kind of target and may be applied in 3D as well as in 2D.

A system and method are provided herein for designing and transmitting RF pulses which cause a reduced off-resonance magnetization transfer saturation. An RF pulse shape may be optimized according to a set of Bloch solutions defining a desired magnetization profile. An RF pulse may be transmitted according to this optimized shape according to a k-space trajectory which traverses a high amplitude portion of the RF pulse more times than one or more low amplitude portions. In addition, a generally alternating slice select gradient may be applied during transmission of the RF pulse.

A method and system for magnetic resonance imaging comprises applying at least one radiofrequency magnetization transfer (MT) pulse to a coronary venous region of a subject positioned within a magnetic field, and acquiring magnetic resonance imaging data from the coronary venous region to produce an image of a coronary venous structure. This technique can be utilized as part of a 3D free-breathing, ECG-triggered gradient-echo Cartesian acquisition of the coronary region. One or more magnetization transfer (MT) preparation pulses are used to enhance the contrast between venous blood and myocardium. The MT preparation results in myocardial signal suppression without any significant signal loss in the arterial or venous blood so as to maintain venous blood signal-to-noise ratio while improving contrast between myocardium and veins. The image of a coronary venous structure can be acquired in connection with an interventional cardiovascular procedure, such as a cardiac resynchronization therapy.

A magnetic recording head used for microwave-assisted magnetic recording includes: a main pole; a spin torque oscillator provided on the main pole, including a high-speed rotating magnetization layer in which the magnetization is rapidly rotated by a spin torque; a trailing shield provided on the spin torque oscillator; and a sub pole magnetically coupled to the trailing shield provided in a medium-facing surface, extending in a vertical direction to the medium-facing surface. Then, a non-magnetic electrode is provided on the outside of a trailing gap in which the spin torque oscillator is provided with respect to a magnetic material of the main pole, the trailing shield, or the sub pole, to prevent the line resistance variation due to the AMR effect or the eddy current. Thus, the variation of the current flowing to the spin torque oscillator can be controlled to achieve stable oscillation.

The present invention is directed, in general, to contrast agents (CA), and methods and systems of using such agents for producing image contrast based on a magnetization transfer (MT) mechanism. The CA comprises a tetraazacyclododecane ligand having pendent arms R, R′, R″ and R′″ that are amides having a general formula: —CR1H—CO—NH—CH2—R2. R1 includes organic substituents and R2 is not hydrogen. A paramagnetic metal ion (M) is coordinated to the ligand. The method, comprises subjecting a CA, in a sample, to a radio frequency pulse. The CA has pendent arms R, R′, R″ and R′″ comprising organic substituents and the ligand further includes a M and a water molecule. A signal is obtained by applying a radio frequency pulse at a resonance frequency of the water molecule. The magnetic resonance system, comprises a magnetic resonance apparatus and the CA, the agent containing a ligand having the above described general formula.

An MRAM has: a memory cell including a first magnetoresistance element; and a reference cell including a second magnetoresistance element. The first magnetoresistance element has a first magnetization fixed layer, a first magnetization free layer, a first nonmagnetic layer sandwiched between the first magnetization fixed layer and the first magnetization free layer, a second magnetization fixed layer, a second magnetization free layer and a second nonmagnetic layer sandwiched between the second magnetization fixed layer and the second magnetization free layer. The first magnetization fixed layer and the first magnetization free layer have perpendicular magnetic anisotropy, and the second magnetization fixed layer and the second magnetization free layer have in-plane magnetic anisotropy. The first magnetization free layer and the second magnetization free layer are magnetically coupled to each other. Center of the second magnetization free layer is displaced in a first direction from center of the first magnetization free layer in a plane parallel to each layer. Whereas, the second magnetoresistance element has: a third magnetization free layer whose magnetization easy axis is parallel to a second direction; a third magnetization fixed layer whose magnetization direction is fixed in a third direction perpendicular to the second direction; and a third nonmagnetic layer sandwiched between the third magnetization fixed layer and the third magnetization free layer. The third magnetization fixed layer and the third magnetization free layer have in-plane magnetic anisotropy.

A device for testing a test specimen for surface faults is equipped for delivering a magnetic flux into the specimen and has induction probes measurement sensors. At least two yoke legs have opposed gap-forming ends with oppositely poled exciter coils between which the test specimen can be guided. Outside ends of the yoke legs opposite the gap-forming ends are connected to one another by a magnetic flux conductor so that the magnetic flux runs perpendicular to the lengthwise direction through the test specimen. To adapt to test specimens of different cross section, the yoke legs can be moved and fixed. Testing of test specimens by means of high-energy magnetic alternating fields improved because the high heat losses produced in this process are adequately dissipated. The device is especially well suited to determine the quality of bars, pipes and the like in a hot rolling mill with high-energy alternating magnetic fields.

Apparatus and methods of generating magnetization transfer contrast images in which signal to noise ratios are improved and / or in which image acquisition times are reduced. In certain embodiments, apparatus and methods which utilize sensitivity and / or non-sensitivity to magnetization transfer effects to improve the contrast of images which are generated. In certain additional embodiments, apparatus and methods for generating magnetization transfer contrast images which exhibit sensitivity to longitudinal and transverse relaxation times of bound and free proton pools, respectively.

The invention provides a magnetic field superposed pipeline fluid magnetization treater, belonging to the water treatment equipment. The treater is characterized in that the structural patterns of bipoles of two permanent magnets or multi-poles of three or four permanent magnets are correspondingly arranged on the same circumferential section of the outer wall of a fluid pipe; or various poles such as the bipoles or multi-poles are set as a plurality of magnet magnetization groups and repeated magnetization structure patterns in the length direction of the pipe; the poles correspond to each other (namely N-N or S-S) and the magnetic lines of force of N-S poles of the magnets are vertical to the length direction of the pipe axle; and various installation methods are adopted. The treater has the following advantages: the structure is simple; the magnetic field intensity can be more than n times that of the single magnet; the magnetization time can be adjusted according to the requirement; and compared with the existing magnetization pattern structures, the magnetization effect of the treater is obviously improved.

There is provided a storage element including a layered construction including a storage layer that has magnetization perpendicular to a surface of the storage layer and whose direction of magnetization is changed corresponding to information, a pinned magnetization layer that has magnetization perpendicular to a surface of the pinned magnetization layer and serves as a standard for information stored in the storage layer, and an insulating layer that is composed of a non-magnetic material and is provided between the storage layer and the pinned magnetization layer.