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公开(公告)号：US5126830A
公开(公告)日：1992-06-30
申请号：US429532
申请日：1989-10-31
申请人： Otward M. Mueller , Lowell S. Smith
发明人： Otward M. Mueller , Lowell S. Smith
IPC分类号： H01L23/427 , H01L23/44
CPC分类号： H01L23/445 , H01L2224/48091 , H01L2924/1305 , H01L2924/13091
摘要： A cryogenic solid-state semiconductor power device, has the actual device chip mounted on a substrate of a material of very high thermal conductivity, which is positioned in a a bath of cryogenic fluid. The substrate may be formed of beryllia, beryllium, alumina, aluminum nitride, diamond and the like materials.
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公开(公告)号：US07126810B1
公开(公告)日：2006-10-24
申请号：US10875458
申请日：2004-06-24
IPC分类号： H01G4/38
摘要： This invention describes a means by which performance characteristics of capacitors can be improved. This is achieved by reducing the temperature, preferably but not exclusively to cryogenic temperatures below 100 K. This is based on the observation that the dielectric strength, dielectric losses and plate losses in many capacitors, such as film capacitors, improve as the temperature is decreased. A cryogenic capacitor bank is also described, which exhibits energy densities up to four times those of conventional, room-temperature capacitor banks. Cryogenic capacitors can be combined with cryogenically operated semiconductors or with superconductors in such a way as to reduce the size, weight, and losses of a complete system.
摘要翻译： 本发明描述了可以提高电容器的性能特性的方法。 这通过将温度降低，优选但不限于低于100K的低温来实现。这是基于以下观察结果：许多电容器（例如薄膜电容器）中的介电强度，介电损耗和板损耗随温度降低而改善 。 还描述了一种低温电容器组，其表现出高达常规室温电容器组的四倍的能量密度。 低温电容器可以与低温操作的半导体或超导体组合，以减小整个系统的尺寸，重量和损耗。
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公开(公告)号：US5017871A
公开(公告)日：1991-05-21
申请号：US407180
申请日：1989-09-14
IPC分类号： G01R33/20 , A61B5/055 , G01R33/385
CPC分类号： G01R33/3852
摘要： A gradient current speed-up circuit, for use in a higher-speed NMR imaging system with a gradient power amplifier and an associated gradient, coil, has a high-voltage power supply which is selectively connected to the associated gradient coil, typical via a plurality of semiconductor switching elements, to supply a pulse of a very high voltage when fast coil rise and fall times are needed. The gradient coil is connected between selected ones of semiconductors devices which are turned on and off in selected patterns, to cause the direction of coil current flow to be determined.
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4.发明授权Low-noise RF preamplifier (especially for nuclear magnetic resonance system) 失效低噪声射频前置放大器（特别适用于核磁共振系统）
公开(公告)号：US4631495A
公开(公告)日：1986-12-23
申请号：US730522
申请日：1985-05-06
摘要： A low-noise radio-frequency preamplifier, especially suited for use in the reception channel of a nuclear magnetic resonance spectrometer and the like, utilizes a low-noise input stage having a plurality of bipolar junction transistors effectively connected in radio-frequency parallel, but with each of the plurality of parallel bipolar transistors isolated from one another for direct current flow through at least one electrode thereof.
摘要翻译： 特别适用于核磁共振光谱仪等的接收通道的低噪声射频前置放大器利用具有多个双极结型晶体管的低噪声输入级，该多个双极结型晶体管以射频平行方式有效连接，但是 所述多个并联双极晶体管中的每一个彼此隔离以直流流过其至少一个电极。
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公开(公告)号：US20120008336A1
公开(公告)日：2012-01-12
申请号：US12831210
申请日：2010-07-06
CPC分类号： B64D11/00 , B60Q3/43 , B64D2011/0038 , F21S9/032 , F21W2107/30 , F21Y2105/10 , F21Y2115/10 , F21Y2115/15 , Y02T50/46 , Y02T50/55
摘要： Described is a novel aircraft lighting system with the potential for achieving increased efficiency, improved thermal management, higher reliability, and longer lifetimes. The proposed approach involves combining solar cells and light-emitting diodes (LEDs), and utilizing the cold temperatures of about −50 degrees centigrade encountered in high-altitude (12,000 m) flight to improve thermal management and efficiency in both components.
摘要翻译： 描述的是一种新颖的飞机照明系统，具有提高效率，改进的热管理，更高的可靠性和更长的寿命的潜力。 所提出的方法包括组合太阳能电池和发光二极管（LED），并利用在高空（12,000米）飞行中遇到的约-50摄氏度的寒冷温度来改善两个部件的热管理和效率。
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6.发明授权Refrigerated superconducting MR magnet with integrated cryogenic gradient coils 失效具有集成低温梯度线圈的冷冻超导MR磁体
公开(公告)号：US5278502A
公开(公告)日：1994-01-11
申请号：US759387
申请日：1991-09-13
IPC分类号： G01R33/3815 , G01R33/385 , G01R33/3873 , G01R33/422 , G01V3/00
CPC分类号： G01R33/385 , G01R33/3815 , G01R33/3873 , G01R33/422 , G01R33/3856
摘要： This invention relates to refrigerated superconducting MR magnets having integrated cryogenic gradient coils. In particular, the amount of eddy currents produced by the magnet are substantially reduced while reducing the size and weight, and, therefore, the cost of the superconducting magnet required to produce an acceptable MR image.
摘要翻译： 本发明涉及具有集成的低温梯度线圈的冷冻超导MR磁体。 特别地，磁体产生的涡流的量大大减小，同时减小了尺寸和重量，并因此降低了产生可接受的MR图像所需的超导磁体的成本。
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公开(公告)号：US5270657A
公开(公告)日：1993-12-14
申请号：US965131
申请日：1992-10-22
申请人： William F. Wirth , Thomas G. McFarland , Robert M. Vavrek , Peter B. Roemer , Otward M. Mueller , John N. Park
发明人： William F. Wirth , Thomas G. McFarland , Robert M. Vavrek , Peter B. Roemer , Otward M. Mueller , John N. Park
IPC分类号： G01R33/385 , G01V3/00
CPC分类号： G01R33/3852
摘要： A gradient amplifier for use in magnetic resonance imaging equipment employs a low voltage DC power supply connected in series between a pair of higher voltage DC power supplies, the latter supplies serving to provide increased power for rapid gradient switching and the former supply providing correction current to produce the desired voltage output. The high voltage DC power supplies preferably comprise multiple DC units which can be combined to provide finer steps of control prior to correction by the lower voltage supply. The low voltage DC power supply preferably comprise one or more linear amplifiers connected in series, or one or more switchmode amplifiers connected in series. The DC power supplies are controlled in an open loop manner from a gradient signal that designates the desired current for the gradient coil and the amplifiers are operated in a closed loop responding to to a feedback signal from the gradient coil.
摘要翻译： 用于磁共振成像设备的梯度放大器采用串联连接在一对高压直流电源之间的低压直流电源，后者用于为快速梯度切换提供增加的功率，而前一个电源提供校正电流 产生所需的电压输出。 高压DC电源优选地包括多个DC单元，其可以组合以在由较低电压源进行校正之前提供更精细的控制步骤。 低压DC电源优选地包括串联连接的一个或多个线性放大器或串联连接的一个或多个开关模式放大器。 直流电源由开路环路控制，该梯度信号指定用于梯度线圈的期望电流，并且放大器响应于来自梯度线圈的反馈信号在闭环中工作。
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公开(公告)号：US5105153A
公开(公告)日：1992-04-14
申请号：US533210
申请日：1990-06-04
申请人： Otward M. Mueller , Peter B. Roemer
发明人： Otward M. Mueller , Peter B. Roemer
IPC分类号： A61B5/055 , G01R33/385 , G01R33/48 , H01F7/20
CPC分类号： G01R33/3852
摘要： A gradient current speed-up circuit, for use in a higher-speed NMR imaging system having an associated gradient coil, has a gradient power amplifier receiving an input analog signal controlling the current in an amplifier output circuit connected in series between first and second portions of a single gradient coil. Semiconductor switching elements selectively connect the coil portion-amplifier-coil portion between first and second potential sources, and are turned on and off in selected patterns to cause a current to be suddenly applied to, and removed from, flow through the associated gradient coil and the amplifier output circuit.
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公开(公告)号：US5010304A
公开(公告)日：1991-04-23
申请号：US431361
申请日：1989-11-03
摘要： A cryogenically-cooled RF power amplifier utilizes a plurality of metal-oxide-semiconductor field-effect transistors configured on a heat sink having at least one surface in contact with a cryogenic fluid, and having input means for coupling RF driving power into the plurality of cryogenically-cooled MOSFETs and output means for coupling an amplified level of RF power from the cooled MOSFETs to an antenna.
摘要翻译： 低温冷却RF功率放大器利用配置在具有至少一个与低温流体接触的表面的散热器上的多个金属氧化物半导体场效应晶体管，并且具有用于将RF驱动功率耦合到多个 低温冷却MOSFET和用于将放大的RF功率从冷却的MOSFET耦合到天线的输出装置。
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公开(公告)号：US4680548A
公开(公告)日：1987-07-14
申请号：US884674
申请日：1986-07-16
CPC分类号： G01R33/3628 , G01R33/34076
摘要： In one embodiment, referred to as the "high-pass" version, the radio frequency (RF) coil is made up of two conductive loop elements, each including serially-connected capacitors. The loop elements are electrically interconnected by axial conductive segments having inherent inductances associated therewith. Electrically, the coil can be viewed as a slow wave delay line structure wrapped around a cylinder and connected to itself. The coil can be energized by connecting a source of RF power across one of the capacitors in the loop elements. In another embodiment, termed the "band-pass" version, the axial conductive segments, as well as the conductive loop elements, are provided with capacitors.
摘要翻译： 在一个实施例中，被称为“高通”版本，射频（RF）线圈由两个导电环路元件组成，每个包括串联连接的电容器。 环形元件通过具有与其相关联的固有电感的轴向导电段电互连。 电气地，线圈可以被看作是围绕圆筒缠绕并连接到其自身的慢波延迟线结构。 通过在环路元件中的一个电容器之间连接RF电源来激励线圈。 在称为“带通”版本的另一实施例中，轴向导电段以及导电环路元件设置有电容器。
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