Provided are batteries and fuel cells incorporating a stripline detector for use in nuclear magnetic resonance (NMR). The stripline batteries and fuel cells can be used for in situ NMR measurement of battery or fuel cell chemistry. Also provided are methods for measuring in situ battery and fuel cell NMR using the stripline batteries and fuel cells of the invention.

According to one embodiment, a coil element includes an extendable and contractible coil and a capacitor. The capacitor is connected to the coil and has an electrostatic capacity which changes due to a physical change in response to extension or contraction of the coil.

Various embodiments of the present disclosure are directed towards a radio frequency (RF) coil comprising a first combination coil and a second combination coil. The first combination coil comprises a first resonant coil and a first resonant shield coupled inductively or by a capacitor, and the first combination coil has a first resonant frequency and a second resonant frequency. The second combination coil comprises a second resonant coil and a second resonant shield coupled inductively or by a capacitor, and the second combination coil has a third resonant frequency and a fourth resonant frequency. The first and second resonant coils are inductively coupled to each other and respectively to the second and first resonant shields. The first and third resonant working frequencies are the same, and the second and fourth resonant isolation frequencies are such that inductive coupling between the first and second resonant coils is negated.

Certain aspects of the present disclosure provide methods and apparatus for performing electron paramagnetic resonance (EPR) spectroscopy on a fluid from a flowing well, such as fluid from hydrocarbon recovery operations flowing in a downhole tubular, wellhead, or pipeline. One example method generally includes, for a first EPR iteration, performing a first frequency sweep of discrete electromagnetic frequencies on a cavity containing the fluid; determining first parameter values of reflected signals from the first frequency sweep; selecting a first discrete frequency corresponding to one of the first parameter values that is less than a threshold value; activating a first electromagnetic field in the fluid at the first discrete frequency; and while the first electromagnetic field is activated, performing a first DC magnetic field sweep to generate a first EPR spectrum.

The present disclosure provides techniques for using opto-isolator circuitry to control switching circuitry configured to be coupled to a radio-frequency (RF) coil of a magnetic resonance imaging (MRI) system. In some embodiments, opto-isolator circuitry described herein may be configured to galvanically isolate switch controllers of the MRI system from the switching circuitry and/or provide feedback across an isolation barrier. Some embodiments provide an apparatus including switching circuitry configured to be coupled to an RF coil of an MRI system and a drive circuit that includes opto-isolator circuitry configured to control the switching circuitry. Some embodiments provide an MRI system that includes an RF coil configured to, when operated, transmit and/or receive RF signals to and/or from a field of view of the MRI system, switching circuitry coupled to the RF coil, and a drive circuit that includes opto-isolator circuitry configured to control the switching circuitry.

Various systems are provided for neck radio frequency (RF) coil assemblies for a magnetic resonance imaging (MRI) system. In one example, a neck RF coil assembly includes a central RF coil array including a first plurality of RF coils configured to cover a neck of a subject to be imaged, an upper RF coil array including a second plurality of RF coils extending upward from the central RF coil array and configured to cover a lower head region of the subject, and a lower RF coil array including a third plurality of RF coils extending downward from the central RF coil array and configured to cover an upper shoulder region of the subject, wherein each RF coil of the first, second, and third pluralities of RF coils comprises a loop portion comprising two distributed capacitance wire conductors encapsulated and separated by a dielectric material.

A nuclear magnetic resonance coil array and a decoupling method thereof, and a nuclear magnetic resonance detection device. The coil array includes: a coil resonant unit and a decoupling network unit, where the coil resonant unit includes multiple coil resonant circuits; the decoupling network unit includes multiple decoupling circuits; where a coil resonant circuit includes a coil and a resonant capacitor; the resonant capacitor in each coil resonant circuit is connected in parallel with the coil; the coils in each coil resonance circuit are equally spaced on a circumference; a decoupling circuit is provided between a positive terminal and a negative terminal of adjacent coils, respectively; each coil is connected to an antenna switching circuit of a nuclear magnetic resonance detection device at the same time.

A local coil for magnetic resonance imaging is disclosed herein. The local coil includes an electrical circuit arrangement and a coaxial cable with an internal conductor and an external conductor surrounding the internal conductor. The two ends of the coaxial cable are connected to the electrical circuit arrangement and the internal conductor and the external conductor together form an antenna loop. The internal conductor and/or the external conductor has at least one interruption and the at least one interruption divides the internal conductor and/or the external conductor into at least two separate segments in each case.

Systems and methods for pre-tuning a main Nuclear Quadrupole Resonance (NQR) probe using a forward sensing probe include a determination of an amount of resonance detuning of the forward sensing probe caused by a moving object entering a field of view of the forward sensing probe. The amount of resonance detuning is used to pre-tune the main probe such that when the moving object enters a field of view of the main probe, the main probe will move back into tune while delivering optimal power to the object for measurement and identification of a material therein.

A coil facility for a magnetic resonance installation and a magnetic resonance installation having such a coil facility are provided. The coil facility in this case includes a double-resonant transmit resonator for two frequencies and a first receiver and a second receiver, each for one of the two frequencies. The coil facility has an actuator system for effecting a relative spatial transposition of the transmit resonator, the first receiver, and the second receiver into various settings. In a first setting, only the first receiver, and in a second setting, only the second receiver, for receiving corresponding MR signals is arranged in an examination space that is at least sectionally surrounded by the transmit resonator.