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公开(公告)号：US20190107590A1
公开(公告)日：2019-04-11
申请号：US16131444
申请日：2018-09-14
IPC分类号： G01R33/3415 , G01V3/14 , G01R33/44 , G01R33/483
摘要： Provided are systems, methods, and apparatus for using nuclear magnetic resonance (NMR) to detect a first material in the presence of a second material within a region of the Earth and within a static magnetic field (such as Earth's magnetic field). These inventions are uniquely suited to detect NMR signals from materials remotely located from a measurement device (e.g., below ice with the device above the ice). They are further useful in detecting first material having relatively short spin-lattice (T1) relaxation time in the presence of second material having longer T1 relaxation time (and therefore slower response to applied magnetic fields). Two pre-polarization currents are used to create pre-polarization magnetic fields stronger than the static magnetic field, each applied over a period of time between the first material's T1 relaxation time and the second material's T1 relaxation time, enabling different ways to null the NMR signal from the second material.
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公开(公告)号：US11215686B2
公开(公告)日：2022-01-04
申请号：US17165099
申请日：2021-02-02
摘要： Electrochemical devices with metal casings have been considered incompatible with nuclear magnetic resonance (NMR) spectroscopy because the oscillating magnetic fields (“rf fields”) responsible for excitation and detection of NMR active nuclei do not penetrate metals. According to the present invention, rf fields can still efficiently penetrate into nonmetallic layers of electrochemical cells (such as a coin cell battery configuration) provided the magnetic field is oriented tangentially to the electrochemical cell electrodes in a “skimming” orientation. As an example, noninvasive high field in situ 7Li and 19F NMR of an unmodified commercial off-the-shelf rechargeable coin cell was demonstrated using a traditional external NMR coil setup. The in operando NMR measurements revealed that irreversible physical changes accumulate at the anode during electrochemical cycling.
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公开(公告)号：US20210318401A1
公开(公告)日：2021-10-14
申请号：US17165099
申请日：2021-02-02
摘要： Electrochemical devices with metal casings have been considered incompatible with nuclear magnetic resonance (NMR) spectroscopy because the oscillating magnetic fields (“rf fields”) responsible for excitation and detection of NMR active nuclei do not penetrate metals. According to the present invention, rf fields can still efficiently penetrate into nonmetallic layers of electrochemical cells (such as a coin cell battery configuration) provided the magnetic field is oriented tangentially to the electrochemical cell electrodes in a “skimming” orientation. As an example, noninvasive high field in situ 7Li and 19F NMR of an unmodified commercial off-the-shelf rechargeable coin cell was demonstrated using a traditional external NMR coil setup. The in operando NMR measurements revealed that irreversible physical changes accumulate at the anode during electrochemical cycling.
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公开(公告)号：US07078897B2
公开(公告)日：2006-07-18
申请号：US10345010
申请日：2003-01-15
IPC分类号： G01V3/00
CPC分类号： G01R33/56341
摘要： An MR method and system of determining elements of the apparent diffusion coefficient tensor in a material with plurality of anisotropic structural units that can be too small to be resolved by direct imaging. MR data is acquired with MR system including pulse sequences, the sequences including imaging or spectroscopy pulse sequences with a series of embedded diffusion-sensitizing gradient waveforms with different gradient strength applied to the material. A nonlinear function of a b-value corresponding to the pulse sequence is defined and the acquired MR data is processed according to defined nonlinear function. Images/maps of the components of the tensor of apparent diffusion coefficients, corresponding to anisotropic structural units, based on the processed MR data, are created. A method of evaluating of the geometrical parameters of lung airways is also described.
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5.发明授权
公开(公告)号：US5905376A
公开(公告)日：1999-05-18
申请号：US699621
申请日：1996-08-19
申请人： David M. Synderman , Donald D. Palmer, Jr. , Mark S. Conradi , Daniel J. Leopold , Charles G. Fry
发明人： David M. Synderman , Donald D. Palmer, Jr. , Mark S. Conradi , Daniel J. Leopold , Charles G. Fry
CPC分类号： G01R33/4641 , G01R33/4625
摘要： A method using nuclear magnetic resonance techniques to detect corrosion within metallic structures such as aluminum under non-ferromagnetic coatings without first having to remove the coatings. The metallic structure is placed within an external static magnetic field. A series of radio frequency preparation and inspection pulses is applied to the metallic with the preparation pulses, and for generating a series of nuclear magnetic resonance response signals with the inspection pulses. The response signals are detected and the amplitudes of the response signals are compared with the spin--spin relaxation time of corrosion for detecting the presence of corrosion in the structure.
摘要翻译： 一种使用核磁共振技术检测非铁磁性涂层等金属结构如铝的腐蚀的方法，而无需先除去涂层。 金属结构放置在外部静磁场内。 一系列射频准备和检查脉冲用准备脉冲施加到金属，并用检测脉冲产生一系列核磁共振响应信号。 检测响应信号，并将响应信号的振幅与用于检测结构中腐蚀的存在的腐蚀的自旋 - 自旋弛豫时间进行比较。
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6.发明授权Detection of thermal damage in composite materials using low field nuclear magnetc resonance testing 失效使用低场核磁共振测试检测复合材料中的热损伤
公开(公告)号：US5786691A
公开(公告)日：1998-07-28
申请号：US791812
申请日：1997-01-30
CPC分类号： G01R33/44
摘要： Thermal damage in resin-matrix composite materials is detected using a low field NMR nondestructive testing technique. The technique involves subjecting the resin-matrix composite material to an NMR measurement of the spin-lattice relaxation (T.sub.1) at a low magnetic field strength and/or the spin-lattice relaxation of local field order (T.sub.1D) at any field strength. Thermal damage is evident as an increase in T.sub.1 and T.sub.1D.
摘要翻译： 使用低场NMR无损检测技术检测树脂基复合材料的热损伤。 该技术包括在任何场强下以低磁场强度和/或局部场序（T1D）的自旋晶格弛豫，对树脂基复合材料进行自旋晶格弛豫（T1）的NMR测量。 T1和T1D的增加会导致热损伤。
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7.发明授权Embedded NMR sensors for cure monitoring and control of composite structures 失效用于固化监测和控制复合结构的嵌入式NMR传感器
公开(公告)号：US5321358A
公开(公告)日：1994-06-14
申请号：US24136
申请日：1993-03-01
摘要： Methods and apparatus for monitoring and controlling cure cycles of composite structures utilize specialized NMR sensor (14) embedded into critical regions in the interior of composite structures (18) to provide in-situ cure state information. Signals developed by the NMR sensors (14) during the curing cycle are processed by an NMR spectrometer (30) to determine selected NMR parameters including T.sub.1, T.sub.2, T.sub.1D, and T.sub.2 * of the materials in the vicinity of the sensor, from which the rigidity of the materials are deduced. Experimental data show clear trends in values of particular NMR parameters taken as time series during cure cycles. Cure cycle control is accomplished using output data from an enhanced NMR spectrometer (30*) to drive temperature and pressure controllers (38, 42) of a curing oven (20*) for real time process control.
摘要翻译： 用于监测和控制复合结构固化周期的方法和装置利用嵌入到复合结构（18）内部的临界区域中的专门的NMR传感器（14）来提供原位固化状态信息。 在固化循环期间由NMR传感器（14）开发的信号由NMR光谱仪（30）处理以确定选定的NMR参数，包括传感器附近的材料的T1，T2，T1D和T2 *， 推导材料的刚性。 实验数据显示在固化循环期间作为时间序列采集的特定NMR参数的值的明显趋势。 使用来自增强型NMR光谱仪（30 *）的输出数据实现固化循环控制，以驱动用于实时过程控制的固化炉（20 *）的温度和压力控制器（38,42）。
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公开(公告)号：US4015464A
公开(公告)日：1977-04-05
申请号：US551913
申请日：1975-02-21
IPC分类号： G01N29/032 , G01N29/036 , G01N29/02 , G01N15/00
CPC分类号： G01N29/032 , G01N29/036 , G01N2291/012 , G01N2291/015 , G01N2291/02416 , G01N2291/02433 , G01N2291/0421
摘要： Apparatus for sensing particles in a fluid medium comprising an ultrasonic resonant cavity for containing a fluid medium. A first transducer on one side of the cavity continuously propagates thereacross ultrasonic compressional waves whose phase and amplitude are perturbed by the presence of particles in the fluid medium. A second transducer positioned on the opposite side of the cavity from the first transducer substantially parallel to and in registry therewith receives the ultrasonic waves and converts them to rf electric waves of the same frequency, the rf electric waves having their phases and amplitudes modulated in response to any perturbations in the ultrasonic waves. The rf waves are amplified and fedback to the first transducer thereby to establish an oscillatory circuit. An attenuator in the oscillatory circuit causes its operation to be marginally oscillatory whereby small changes in the amplitude of the rf waves caused by any perturbations in the ultrasonic waves produce relatively large changes in the amplitude thereof. A detector responsive to perturbations in the rf wave demodulates the amplified rf wave to produce signals indicative of the presence of particles in the fluid medium. Thus, enhanced sensitivity to small changes in the ultrasonic properties of the fluid medium caused by the presence of particles therein is achieved.
摘要翻译： 用于感测流体介质中的颗粒的装置，包括用于容纳流体介质的超声谐振腔。 空腔一侧的第一个传感器连续传播超声波压缩波，其相位和幅度受流体介质中颗粒的存在扰动。 位于与第一换能器相反侧的与第一换能器相反侧的第二换能器基本上平行于并与之对准地接收超声波并将其转换成具有相同频率的rf电波，其中rf电波具有响应的调制幅度 超声波中的任何扰动。 rf波被放大并反馈到第一个换能器，从而建立振荡电路。 振荡电路中的衰减器使其操作略微振荡，从而由超声波中的任何扰动引起的rf波的振幅的小的变化产生其幅度相对较大的变化。 响应于rf波中的扰动的检测器解调放大的rf波以产生指示流体介质中颗粒存在的信号。 因此，实现了由其中存在颗粒引起的流体介质的超声波特性的小变化的增强的敏感性。
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