554 results about "Magnetic susceptibility" patented technology

An assembly with a substrate, nanomagnetic material and magetoresistive material. The nanomagnetic material has a saturation magentization of from about 2 to about 3000 electromagnetic units per cubic centimeter; and it contains nanomagnetic particles with an average particle size of less than about 100 nanometers. The average coherence length between adjacent nanomagnetic particles is less than 100 nanometers.

A method for geographical surveying includes the steps of determining an observation grid comprising observation points above a solution volume in the ground; making gravitational measurements at the observation points over a survey area; compiling a matrix having elements relating a set of gravitational accelerations and gravity gradient values at the points to the mass values for volume elements in the solution volume; and calculating the three-dimensional density distribution of the volume under the survey area based on the gravitational measurements and the inverse of the matrix. By measuring the magnetic field and gradient at the observation points, the three-dimensional magnetic susceptibility distribution of the volume under the survey area can be determined.

A probe instrument using room-temperature sensor(s) that can measure variations in magnetic susceptibilities. The instrument has sufficient resolution to monitor paramagnetic materials in a human body, such as iron in a human liver, by noninvasively examining patients with iron-overload diseases. The instrument includes room temperature magnetic sensors, and detects the sample, that is, the tissue response to an alternating current field applied by an applied field coil. The applied field coil dimensions are chosen so that the applied field is optimized for maximum response from the liver while minimizing the effects due to the overlying abdominal tissue and at the same time not unduly increasing the sensitivity of the instrument to the lung. To overcome variations in the sensor output due to fluctuations in the applied field, change in the ambient temperature and mechanical relaxation of the instrument, the sensor-sample distance is modulated. The detector assembly is oscillated while the examined patient remains stationary. An improved water-bag technique is employed to eliminate background tissue response. The detector assembly forms part of a probe instrument for performing noninvasively the paramagnetic concentration of a patient.

A microfluidic device for manipulating particles in a fluid has a device body that defines a main channel therein, in which the main channel has an inlet and an outlet. The device body further defines a particulate diverting channel therein, the particulate diverting channel being in fluid connection with the main channel between the inlet and the outlet of the main channel and having a particulate outlet. The microfluidic device also has a plurality of microparticles arranged proximate or in the main channel between the inlet of the main channel and the fluid connection of the particulate diverting channel to the main channel. The plurality of microparticles each comprises a material in a composition thereof having a magnetic susceptibility suitable to cause concentration of magnetic field lines of an applied magnetic field while in operation. A microfluidic particle-manipulation system has a microfluidic particle-manipulation device and a magnet disposed proximate the microfluidic particle-manipulation device.

A light emitter drive circuit for an oximeter which utilizes a single inductor for driving multiple light emitters. The inductor is connected to a switching circuit to multiple energy storage circuits, such as capacitors. These are alternately charged up, using the same inductor. Subsequently, the capacitors are alternately discharged for their corresponding light emitters through the same inductor. Also, the magnetic susceptibility of the LED drive circuit is reduced by using magnetic flux canceling in the inductor. In one embodiment, a toroidal inductor is used with geometric symmetry and its magnetic flux. In another embodiment, a dual core closed bobbin shielded inductor is used.

A medical device suitable for use with magnetic resonance imaging techniques includes a component that is formed from a refractory metal, a precious metal, an alloy comprising a refractory metal, an alloy comprising a precious metal, and/or alloy comprising at least one refractory metal and at least one precious metal. The component has a magnetic susceptibility less than about 300×10⁻⁶ cgs, and has a low radiopacity such that the component can be visualized under fluoroscopy.

A transverse rf saddle coil (30) for use in NMR is affixed in intimate thermal conract on one surface of a ceramic coilform (23) of high thermal conductivity. The probe is mostly for use with solid samples at high fields where the axis of the coilform is not alignedwith the main field. An orthogonal rf coil (1) is mounted in intimate thermal contact to the first saddle coil (30) via a ceramic spacer or coilform (2). The coilform is cooled by high-velocity gas flow and is also often associated with bearing exhaust gas from a high speed sample spinner. The two coils are tuned to different rf frequencies with circuits capable of supporting high rf currents. The rf coils (30, 1) may be magnetically compensated and expansion controlled, and passive geometric compensation of magnetic susceptibility effects from a sample spinner stator may also be incorporated. Novel coil mounting techniques, including metallurgical bonds to ceramics and capturing by dielectric clam-shells, are also disclosed.

A high magnetic susceptibility nanomagnetic material that may be attached to recognition molecules and other therapeutic biological materials so as to be targeted to specific biologic tissues, thereby enabling the presence of the targeted tissue to be detected under magnetic resonance imaging with much greater sensitivity. Also a stent coated with such nanomagnetic material to enable artifact free imaging of such stent under magnetic resonance imaging.

A wireless headset capable of receiving audio signals transmitted wirelessly and compatible for use in an MRI scanner is disclosed. The headset includes a first wireless module connected to the first earphone and a second wireless module connected to the second earphone. Each wireless module is electrically connected to a speaker in the respective earphone. The first wireless module receives the audio signal from a remote source and coordinates transmission of the audio signal to each of the speakers. The compact nature of each earphone minimizes the length of wire runs. In addition, the headset is made of materials having low magnetic susceptibility such that they will not be affected by the magnetic field from the MRI scanner.

There is provided a semiconductor package capable of protecting a passive element, a semiconductor chip, or the like included in the package from external force and having enhanced Electro Magnetic Interference (EMI) and Electro Magnetic Susceptibility (EMS) characteristics and a manufacturing method thereof. The semiconductor package includes a substrate having at least one cavity formed in a side surface thereof and an electrode provided within the cavity; at least one electronic component mounted on a surface of the substrate; a mold part sealing the electronic component and having insulating properties; and a shield part attached to the mold part to cover an outer surface of the mold part, electrically connected to the electrode provided within the cavity, and having conductive properties.

There are provided a semiconductor package including an electromagnetic shielding structure having excellent electromagnetic interference (EMI) and electromagnetic susceptibility (EMS) characteristics, while protecting individual elements in an inner portion thereof from impacts, and a manufacturing method thereof. The semiconductor package includes: a substrate having ground electrodes formed on an upper surface thereof; at least one electronic component mounted on the upper surface of the substrate; an insulating molding part including an internal space in which the electronic component is accommodated, and fixed to the substrate such that at least a portion of the ground electrode is externally exposed; and a conductive shield part closely adhered to the molding part to cover an outer surface of the molding part and electrically connected to the externally exposed ground electrodes.

A system and method for determining the state of health of a battery. In particular, the present invention is related to a system and method for determining the state of health of an electrochemical battery cell by obtaining state of charge measurements for the battery cell, and using the state of charge measurements to calculate the state of health of the battery cell, wherein the state of charge measurements are based on the magnetic susceptibility of the battery cell. The system includes a sensing device for measuring the magnetic susceptibility of the battery cell, and a computing device for performing the steps of the disclosed method.

Subterranean hydrocarbon reservoirs are analyzed by characterizing the relative presence and character of microfractures in rock samples from the reservoirs. Core samples are saturated with a suspension of magnetite particles of known concentration. The samples are then subjected to an applied magnetic field of known strength. The anisotropy of magnetic susceptibility, or AMS, of the samples is then observed, providing a measure of grain orientation in the samples. The characteristics of the microfractures in the samples are thus available to characterize the reservoirs, and in particular the contribution of the microfractures to the porosity and permeability of formations in the reservoirs.

The invention provides a geophysical prospecting technical method for recognizing the lithology of petrosilex by using the combined characteristics of gravity-magnetic-electronic anomaly, which comprises the following steps of collecting and recording the physical characteristics of drill core; carrying out cluster analysis on the density, magnetic susceptibility and resistivity of rock by using k-means clustering and obtaining the clustering code of the drill core; carrying out gravity and magnetic anomaly stripping to the gravity and magnetic prospecting result for obtaining the anomaly and adopting the same clustering to conduct three-dimensional anomaly coding; and combining the clustering code of the physical characteristics of rock with gravity-magnetic-electronic anomaly code for reflecting the lithology of each petrosilex in an exploratory area. By developing the method for recognizing the lithology of petrosilex by using integral gravity-magnetic-electronic from qualitative speculation to quantitative statistics, the invention reduces human subjective factors from experience, avoids the situation that different geological interpreters obtain different results and improves the recognition effect of petrosilex.

The MRI apparatus of the present invention performs a pulse sequence for applying successively 180° pulses 102, 103 . . . after application of a 90° pulse 101 at constant intervals and applying readout magnetic fields 111 during the interval between pairs of 180° pulses while the polarity of the magnetic field 111 is inverted several times to collect a plurality of gradient echo signals that are phase encoded differently. Here, the application of the readout gradient magnetic field is controlled such that generation of the gradient echo signals does ot coincide with generation of the spin echo signal. The image reconstruction is performed by using only T2* weighted gradient echo signals to obtain images reflecting difference in magnetic susceptibility and inhomogeneities in local magnetic fields.

The estimation accuracy of a magnetic susceptibility value of tissue is improved by computing an edge image which represents the edge of the tissue on a magnetic susceptibility distribution and to reduce background noise without lowering the magnetic susceptibility value of the tissue. The present invention computes an absolute value image and a phase image from a complex image obtained by MRI, from the phase image, computes a low frequency region magnetic susceptibility image in which background noise is greater than a desired value, computes an edge information magnetic susceptibility image and computes a high frequency region magnetic susceptibility image, computes an edge mask from the edge information magnetic susceptibility image, smooths a magic angle region from the edge mask and the low frequency region magnetic susceptibility image and finally smooths a high frequency region using the high frequency region magnetic susceptibility image.