摘要:
Magnetic resonance device (1) with an assembly (3) having a recess, in which a gradient coil unit (9) is attached with at least one attachment means (15, . . . 15D), the attachment means (15 ... 15D) having two members (21,23), between which an elastic element (25) is disposed, only one of the members (21,23) in each instance being in contact with either the gradient coil unit (9) or the assembly (3), with the attachment means (15, . . . 15D) acting as an attachment means (15, . . . 15D) having no elastic element (25) in a first attachment state, in which at least a minimum force (FMIN) presses the two members (21, 23) together, in that the two members (21, 23) have stop surfaces (31), which are in contact with each other due to the minimum force acting on the members (21, 23) [lacuna] compressed elastic element (25) and with the attachment means (15, . . . 15D) acting as a spring unit in a second fixing state, in that the elastic element (25) pushes the members (21, 23) apart in the event of forces smaller than the minimum force (FMIN) and causes the attachment means (15, . . . 15D) to be fixed in relation to the gradient coil unit (9) and the assembly (3). This has the advantage that there is no loosening of the attachment means in particular even in the event of thermal fluctuations.
摘要:
Supporting tube made from reinforced plastic for magnetic resonance scanners with tracks for a patient bed and load-bearing shells formed on both sides, opening upwardly, with fastening members on the undersides is manufactured including the guide rails and the under embedded fastening members from mold-cast plastic and is locally provided with cast-in reinforcements only in the region bf the load-bearing shells.
摘要:
New initiators which are suitable for cationic polymerization have the following structure: ##STR1## such that following apply: R.sup.1 and R.sup.2 are alkyl or cycloalkyl or they, together with the S atom, form a heterocyclic ring,R.sup.3 is H or alkyl,R.sup.4, R.sup.5, R.sup.6, and R.sup.7 are H, alkyl, or alkoxy,X.sup.-- is a non-nucleophilic anion.Reaction resin mixtures with initiators of this type contain, in addition to a cationically polymerizable monomer and/or oligomer, 0.01 to 10% by mass of the initiator.
摘要:
At least one embodiment is directed to a combination of an MR tomograph and a positron emission tomograph having avalanche photodiodes as reception elements. In at least one embodiment, the intention is to ensure that the avalanche photodiodes are kept at a constant temperature despite the exposure to heat from the MR components. It is proposed, in at least one embodiment, that cooling by Peltier elements 5 should be provided.
摘要:
An electrical device is produced using components that are designed and fabricated of material that is substantially free of flame retardant additives. At least some of the components are coated with a flame retardant coating to give those components fire protection capability that satisfies applicable regulations. The frame retardant coating can be applied to the components either before assembly thereof to form the electrical device, or can be applied to the assembled apparatus.
摘要:
For generating of magnetic resonance exposures of an examination subject, a dielectric element with high dielectric constant is positioned on the examination subject to locally influence the B1 field distribution, the dielectric element being formed primarily of material whose magnetic resonance line(s) is/are shifted by at least a specific degree relative to the magnetic resonance line of water protons for a given magnetic field. In a measurement for generation of a magnetic resonance exposure a measurement sequence is used, such in the acquisition of the raw image data the dielectric material of the dielectric element supplies no signal contributions for the image generation and/or the signals caused by the dielectric material of the dielectric element can be separated from the signals caused by the examination subject.
摘要:
A local coil unit for a magnetic resonance apparatus, which radiates a radio-frequency field into an examination subject, has a housing and at least a part of the housing is formed of an insulating dielectric material that passively compensates for an inhomogeneity in the high-frequency field in the subject. The material has a relative dielectric value εr of greater than 50, preferably greater than 100, and a dielectric loss factor tan δ of less than 2.5×10−2, preferably less than 1×10−3. In the dielectric material displacement currents are generated which create an additional magnetic field that compensates for the minima in the B1 field as a result of the eddy currents arising in the patient due to the radio-frequency radiation.
摘要:
The invention relates to flexible compounds that are made of a thermoplastic elastomer and a filler having increased thermal conductivity, and to flexible heat-conducting tubes produced on the basis thereof that are especially useful as heating or cooling tubes. The inventive mixtures have a thermal conductivity in the range of from 0.5 to 2 W/mK.
摘要:
A device is disclosed for superposed magnetic resonance imaging and positron emission tomography imaging. The device includes a magnetic resonance imaging magnet which defines a longitudinal axis; a magnetic resonance imaging gradient coil arranged radially within the magnetic resonance imaging magnet; a magnetic resonance imaging RF coil arranged radially within the magnetic resonance imaging gradient coil; and a multiplicity of positron emission tomography detection units arranged in pairs opposite one another about the longitudinal axis. In at least one embodiment, the many positron emission tomography detection units are arranged radially within the magnetic resonance imaging gradient coil and can be inserted into the device and can be removed from the device along the longitudinal axis. In at least one embodiment, a carrier tube is provided having a multiplicity of pockets, which in each case extend along the longitudinal axis, for accommodating at least one positron emission tomography detection unit.
摘要:
A dielectric element for positioning on an examination subject for locally influencing the B1 field distribution during magnetic resonance data acquisition contains a relaxation agent bound to mutually separated particles. The relaxation agent incorporates a paramagnetic substance. In a corresponding method for acquiring magnetic resonance data from an examination subject, such a dielectric element is positioned on the examination subject for locally influencing the B1 field distribution, by homogenizing the B1 field of a magnetic resonance apparatus.