A wireless power transfer system (1) includes a primary coil (2) for generating an oscillating electromagnetic field for wirelessly transferring power to a secondary coil. The system also includes emitting coils (6) arranged to generate an electromagnetic field for exciting a nuclear quadrupole resonance in the biological material of an animal (7) exposed to the electromagnetic field generated by the emitting coils. The system also includes detecting coils (6) for detecting the absorption and/or emission of electromagnetic radiation by and/or from the excitation of the nuclear quadrupole resonance. The system is arranged, when the detecting coils detect the absorption or emission of electromagnetic radiation, to prevent the primary coil from generating, or to cause the primary coil to reduce the amplitude of, the oscillating electromagnetic field.

Embodiments of the invention provide an arrangement where a small detection coil of an NQR system is mounted on the end of a carrier such as a prodder stick, and is then carried by the carrier into the very near vicinity of, and more particularly for example into contact with, a possible target explosive device. Because the detection coil is brought into contact with or into the very near vicinity of the target, the transmitted NQR signals, and the resultant QR response, can be much lower power, to the extent that such a system can be made fully man-portable, and also be much lower cost to manufacture. As a consequence, NQR explosive detections systems may be deployed in larger numbers than has heretofore been possible, thus increasing the certainty of, and hence safety, of landmine detection, and improving clearance rates.

A method for probing the properties of nanoscale materials, such as 2D materials or proteins, via nanometer-scale nuclear quadrupole resonance (NQR) spectroscopy using individual atom-like impurities in diamond. Coherent manipulation of shallow nitrogen-vacancy (NV) color centers enables the probing of the NQR spectrum of nanoscale ensembles of nuclear spins. Measuring the NQR spectrum at different magnetic field orientations and magnitudes and fitting to a theoretical model allows for the extraction of atomic structural properties of the material with nanoscale resolution.

The present invention is directed to a detector and a method for detecting explosive substances and drugs by nuclear quadrupole resonance designed for screening baggage and people at border crossing points in airports, ports, railway stations and in other locations which require strong measures against terrorism and smuggling of prohibited substances such as explosives and drugs. According to the present invention, the detector comprises a central processing unit (UC) which connects to a storage, data processing, and interface unit (USPI) provided with a user console (IC) and a with a head (CS1) for scanning explosives/drugs around the legs and a head (CS2) for scanning suspicious objects on the ground or that cannot be moved, and which has a compact build and includes all the hardware modules and software components necessary for operation, being made up of a radio processing system (SPR) which includes a programmable RF signal generator (DDS) which transmits RF pulses to a power amplifier (AP) coupled to an interface for gain control and for the acquisition of the reflected signal level (IAP), a series-parallel tuning circuit (CA) consisting of a flat spiral ferrite-core coil (L) and two variable capacitors (CV1, CV2) driven by two stepper motors (M1, M2) which are controlled by an automatic tuning matching module (WIAA) through control interfaces which are, in principle, already known. According to the present invention, the detection method consists of: measuring the ambient temperature with a sensor; digitally converting the temperature value and reading it in the software application which controls the radio processing system (SPR); calculating the NQR frequency by using the coefficient of variation specific to each target substance and transmitting that value (fo) to a programmable RF signal generator (DDS); ordering, by means of the software application, RF pulses with a certain duration (TRF) during which the signal frequency will increase in 10 stages within a predetermined range i around fo, i.e. fof/2; identifying the substance by real-time discrimination of the received signal based on a set of four combined criteria applied to the spectral response obtained by means of the fast Fourier transform FFT.

A system and method for detecting a nucleus of interest in a chemical using a nuclear quadrupole resonance transition. An excitation pulse is used to excite one or more nuclei of interest, if they present in a sample, to an excited state, the energy of which depends on the magnetic field in the sample. The magnetic field in the sample is modulated, after the end of the excitation pulse, while the nuclei of interest decay from the excited state, so that the radiation they emit is frequency modulated. The frequency modulation is detected in the emitted radiation. In some embodiments a DC magnetic field is applied to the sample, during the application of the excitation pulse, to tune the frequency of the transition being excited.

Apparatus including an electrically conductive housing, an electrically non-conducting pipe carrying the slurry through the housing, one or more primary coils each encircling the pipe within the housing and having a capacitor unit coupled thereto with a capacitor unit value chosen so that a primary coil series resonance is formed close to the value of a target magnetic resonance frequency, and for each primary coil, a drive coil and associated electrical network positioned to magnetically couple the drive coil to that primary coil. An impedance monitor coupled to each electrical network measures a complex input impedance thereof. An RF transmitter transmits a signal to one or more of the electrical networks with a frequency approximately equal to the target magnetic resonance frequency, and an RF receiver receives from each electrical network magnetic resonance signals from the target and forms an output signal of detected signals.

Aspects of the present disclosure include methods, systems, and non-transitory computer readable media for receiving a plurality of reception magnetic signals, determining state information associated with each marker of the plurality of markers based on a corresponding transmission magnetic signal of the plurality of transmission magnetic signals and a corresponding reception magnetic signal of the plurality of reception magnetic signals, and determining tag information based on the state information of the plurality of markers.

A wireless power transfer system (1) includes a primary coil (2) for generating an oscillating electromagnetic field for wirelessly transferring power to a secondary coil. The system also includes emitting coils (6) arranged to generate an electromagnetic field for exciting a nuclear quadrupole resonance in the biological material of an animal (7) exposed to the electromagnetic field generated by the emitting coils. The system also includes detecting coils (6) for detecting the absorption and/or emission of electromagnetic radiation by and/or from the excitation of the nuclear quadrupole resonance. The system is arranged, when the detecting coils detect the absorption or emission of electromagnetic radiation, to prevent the primary coil from generating, or to cause the primary coil to reduce the amplitude of, the oscillating electromagnetic field.

A system and method for detecting a nucleus of interest in a chemical using a nuclear quadrupole resonance transition. An excitation pulse is used to excite one or more nuclei of interest, if they present in a sample, to an excited state, the energy of which depends on the magnetic field in the sample. The magnetic field in the sample is modulated, after the end of the excitation pulse, while the nuclei of interest decay from the excited state, so that the radiation they emit is frequency modulated. The frequency modulation is detected in the emitted radiation. In some embodiments a DC magnetic field is applied to the sample, during the application of the excitation pulse, to tune the frequency of the transition being excited.

Technologies applicable to NMR spin-echo amplitude estimation are disclosed. Example methods may calibrate for distortion of a shape and estimated amplitude of measured NMR spin or gradient echoes. NMR spin or gradient echo measurements may be performed on a sample. The measured NMR spin or gradient echoes may be used to calculate an echo-shape calibration factor. The echo-shape calibration factor may estimate an effect of echo shape on estimated spin or gradient echo amplitude(s) of the NMR spin or gradient echoes. The echo-shape calibration factor may be used to correct for underestimation or overestimation of the spin or gradient echo amplitude(s).