Abstract: The present invention is a method to rapidly determine the fluid-flow permeability of porous media with nuclear magnetic resonance (NMR). The method can be applied to measurements of permeability in fluid-saturated earth formations using NMR logging tools.

Abstract: A nuclear magnetic resonance imaging system with the intercom facility in which the disturbing and potentially harmful large noise due to the application of the reading gradient field pulses can be reduced at the exterior of the examination room. In the system, a connection between the microphone and the loudspeaker for transmitting the sounds generated inside the examination room to the exterior of the examination room is controlled according to the pulse sequence specified by the sequence controller such that the microphone and the loudspeaker are disconnected whenever the application of the reading gradient field pulse takes place.

Abstract: Apparatus for analysis of flowing streams of liquids, flowable solids or mixed liquids and solids by nuclear magnetic resonance techniques. The apparatus is sufficiently small, economical and easy to operate so that it is useful for making measurements in applications such as the production of foods and the like.

Abstract: Acoustic ringing and adverse effects from variations in the NQR detection of explosives and narcotics are minimized or eliminated. A specimen is irradiated with a modified steady state steady state free precession (SSFP) pulse sequence which combines a phase-alternated pulse sequence (PAPS) with a non-phase-alternated pulse sequence (NPAPS). The resulting signals from the PAPS and NPAS may then be coadded to cancel out the FID contributions to the signals. By canceling out the FID contributions to the signals, the effects of probe ringing and other extraneous responses, as well as the effect of temperature variation, are minimized or removed. The present method is especially effective in the detection of explosives and narcotics having .sup.14 N or .sup.35,37 Cl nuclei. A steady state free precession pulse which is especially useful with the method of the present invention is the strong off-resonance comb (SORC).

Abstract: A borehole logging tool comprises a Nuclear Magnetic Resonance (NMR) tool and is pulsed according to a selected sequence. An interpretation is performed which involves a singular value decomposition and compression of data obtained by the tool. The compressed data is then subjected to a nonegative, linear least square fit to obtain a distribution function. The distribution function is used in determining bound fluid volume, unbound fluid volume, total porosity, spin-lattice relaxation time, spin-spin relaxation time, and mean relaxation time using only the pulse NMR tool.

Abstract: Slaved radio frequency field and light polarization magnetometer. The polarization direction (P) is slaved perpendicular to the field (Bo) to be measured, as well as the radio frequency field (Brf). Application to the measurement of weak magnetic fields such as the geomagnetic field.

Abstract: A resonator arrangement 10 serves for electron spin resonance spectroscopy. It comprises an upper carrier plate 30, a long center portion 32, 33, 40, 41 and a lower resonator section 45, 46, 47. In the area of the center portion 32, 33, 40, 41, there is provided at least one separating plane 50, 51 along which the resonator arrangement 10 can be divided into an upper part 52 and a lower part 52, it being possible to connect a plurality of different lower parts 53 to one and the same upper part 52.

Abstract: An apparatus and method for identifying the presence of biological molecules labeled with isotopes that are identifiable and distinguishable by their responses to nuclear magnetic resonance. The method features the use of labels that are:1) not radioactive or only weakly radioactive, therefore not hazardous to handle, and have a long storage life.2) small in molecular weight, thus not significantly changing the electrophoresis migration rate of the labeled material.3) available as several distinguishable labels, thereby enabling simultaneous detection of several classes of molecules.

Abstract: The invention concerns a nuclear resonance well logging tool for insertion into a borehole with a permanent magnet which is magnetized perpendicularly to its axis and with means to transmit and to detect high frequency signals whereby the transmission and detection coils are orthogonal. The arrangement is configured for CW operation. The permanent magnet or the transmission and detection coil arrangement may rotate around the axis in order to modulate the nuclear resonance signals.

Abstract: A gradient magnetic field-generating coil assembly of MR imaging apparatus has a cylindrical core member for carrying coil windings that is divided into at least two cores at a central portion of a magnet bore, a gap is set up between the two cores at the central portion of the magnet bore and each core is provided at its opposite ends with parts for fixing it to the magnet, whereby the natural vibration frequency of the core can be deviated from an exciting force frequency and sound prevailing in the outside of the core and sound in the inside can be brought into interference with each other to thereby suppress vibration of the cores at the central portion of the magnet bore and reduce noise.

Abstract: The invention provides a specific measure of iron stores in vivo using magnetic resonance imaging. T.sub.2 relaxation times in both lower-to-mid field strength magnetic resonance imaging instruments and a higher field strength instrument is evaluated. T.sub.2 obtained at the higher field strength instrument is subtracted from T.sub.2 obtained at the lower field strength instrument. This difference, T, is then correlated with a quantitative measure of the iron stores in vivo in the scanned tissue. A two-dimensional or multidimensional map of the scanned tissue is then constructed on the basis of T to visually identify different tissue types as being normal or abnormal, either through a visual determination based on gray scales or a numeric comparison based on quantitative measure. The introduction of artificial or nonbiological substances as opposed to natural ferritin, is permitted for further diagnostic use by application of this methodology.

Abstract: A visible and/or MRI visualizable permanent image is formed in a gel in a container which maintains the gel a dimensionally stable shape, which gel contains uniformly dispersed therein in storage stable form at last one radiant energy, e.g., ionizing radiation, polymerizable monomer in a concentration effective to form an insoluble polymer in the gel which alters the relaxation time of the solvent in any area thereof in which the polymer is formed, e.g.

Abstract: 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.

Abstract: Tissue mimicking phantoms for NMR imagers are produced having a base tissue mimicking material enclosed within a sealed container. The base tissue mimicking material is a gel solidified from a mixture of agar, animal hide gelatin, water, glycerol, and anti-bacterial agents such as n-propanol, p-methylbenzoic acid, and formaldehyde. The formaldehyde also serves to cross link the animal hide gel and thereby raise the melting point of the tissue mimicking material to a temperature above normal ambient temperatures. This base tissue mimicking material is stable both in dimensions and NMR properties over long periods of time. Contrast resolution inclusions are formed within the base tissue mimicking material which have T.sub.1, T.sub.2, or both which differ from the corresponding values for the base tissue mimicking material, thereby allowing these inclusions to be imaged and distinguished from the surrounding material.

Abstract: A combined fermenter and measuring tube for NMR throughflow spectroscopy on cell suspensions in which the measurement tube has a capacity of 3 to 20 ml in the measuring zone of the magnet and a fermenter is a premagnetization reservoir of greater cross section of a capacity of at least 100 ml in the repolarization range. A liquid circulator is provided to provide a throughflow rate of 5 to 250 ml/s in the measuring tube.

Abstract: A magnetic-resonance imaging apparatus has superconducting magnets for generating a large uniform magnetic field within a predetermined volume. Within that volume, coils for generating magnetic field gradients are supported on a bobbin, enabling an object within the bobbin to be investigated. The coils on the bobbin are subject to forces but are rigidly connected to the bobbin. Therefore, energy is transmitted to the bobbin which can cause the bobbin to vibrate and so generate noise. To dissipate that energy, the coils are attached to tubes, or other hollow members, on the bobbin, which tubes or hollow members contain movable bodies such as particulate material. The energy due to the forces on the coils cause the movable bodies to move and collide, so dissipating the energy and reducing the noise.

Abstract: A local gradient coil adapted for use with stereotaxic devices includes an opening in the coil form positioned to minimize the disruption to the gradient fields and a bearing for moving the form with respect to the stereotaxic frame so that the opening may be limited in area and yet provide essentially unrestricted access to the patient. The windings in the neighborhood of the opening may be diverted by modifying the stream function of the windings in a manner to minimize the effect of the opening on the gradient field.

Abstract: Pulsed NMR system for industrial measurements comprising sample throughput system (P, LI, V1, V2) and user system controls (104) to establish digitized free induction decay (FID) curves (C), from which fast Gaussian, slower modified Gaussian and exponential components are determined using a Marquardt-Levenberg iteration technique, and using regression techniques to correlate the FID curve components to the physical quantities of the target nuclei.

Abstract: Pulsed NMR system for industrial measurements comprising sample throughout system (P, LI, V1, V2) and user system controls (104) to establish digitized free induction decay curves (C), from which Abragam, Gaussianand exponential components are determined using a Marquardt-Levenberg iteration technique, and using regression techniques to correlate the curve components to the target nuclei.

Abstract: Improved NMR sample tube shapes and inserts for standard tubes to shape the sample for greater homogeneity to provide symmetry of liquid sample and tube to a greater distance from the observe region for the same volume of sample as used in the prior art.

Abstract: Electron spin resonance spectrometers comprise a sample cavity located between the poles of a permanent magnet, means for applying microwave energy to the cavity, means for measuring the frequency of the microwave energy applied to the cavity, means for controlling the magnetic field strength in the cavity, means for detecting changes in cavity Q and accordingly changes in the level of microwave power reflected back from the cavity, and means for analyzing the changes in reflected power. In accordance with one aspect, a nuclear magnetic resonance probe including a standard sample is placed adjacent the sample cavity, means are provided for measuring the nuclear magnetic resonance frequency in the standard sample, calculating the magnetic field to which the sample and the adjacent cavity are subjected therefrom and applying the results of the calculation to control the magnetic field strength in the cavity.

Abstract: A method is provided for carrying out proton magnetic resonance thermal analysis measurements. To this end, the method provides locating a sample within a coil forming part of an RF tuned circuit and applying a magnetic field to the sample. The sample is heated in accordance with a predetermined temperature regime. Pulsed RF energy is applied to the coil to generate a pulsed RF electromagnetic field which is applied to the sample. The magnitude of the magnetic field is adjusted to insure that the NMR frequency of the sample is substantially identical to the RF frequency. The resonant frequency of the tuned circuit is adjusted to compensate for temperature induced changes in the tuned circuit components and the sample. The energy of the pulsed RF energy is adjusted to obtain an optimum output from the RF tuned circuit. The RF tuned circuit output is recorded as a function of either time or temperature of the sample.

Abstract: A gradient coil for generating a periodically changing read-out gradient in a magnetic resonance imaging apparatus is operated in a series resonant circuit having a capacitor. One of the elements of the series resonant circuit is charged before the beginning of each read-out gradient. The gradient coil can be charged with current, or the capacitor can be charged with voltage. Such operation either avoids or significantly shortens the transient effect which occurs after excitation of the nuclear spins. The use of a series resonant circuit instead of a parallel resonant circuit significantly reduces the voltage load on the gradient amplifier, so that the gradient amplifier can be constructed simpler and more inexpensively.

Abstract: A current sensor using a resonance directional magnetometer which includes a magnetic circuit having a gap and a device supplying a voltage representative of a magnetic field produced in the gap by a current when the current passes through the circuit. The value of the field is a function of the intensity of the current. The device is a resonance directional magnetometer having a sample with resonant spins placed in the gap and exposed to a magnetic field having a polarization parallel to the field produced in the gap or coinciding with this field and a measuring device for exciting the resonance and detecting the excited resonance and for supplying a voltage representative of the amount of excited resonance.

Abstract: The present invention is a method to rapidly determine the fluid-flow permeability of porous media with nuclear magnetic resonance (NMR). The method can be applied to measurements of permeability in fluid-saturated earth formations using NMR logging tools.

Abstract: An NMR angiogram is produced from two data sets acquired using a fast pulse sequence. One data set is acquired with a readout gradient having a first moment of zero at each refocusing pulse and a first value at each acquired echo signal. A second data set is acquired with a readout gradient having a first moment of zero at each refocusing pulse and a second value at each acquired echo signal. Signals from stationary tissues are suppressed with a dephasing gradient pulse in the slice select direction applied after each refocusing pulse, and a corresponding rewinder gradient pulse is applied after each acquired echo signal.

Abstract: MRI T1 relaxometry is performed using a single fixed strength magnetic background field for RF signal transmission and reception thus greatly simplifying RF circuitry design and/or adjustment. Switched differing strength background magnetic fields are employed at other times in the relaxometry cycle so as to predominate the NMR T1 relaxation parameter value and thus permit relaxometry determinations of T1 values versus magnetic field strength (or the equivalent corresponding NMR RF frequency) at N data points using as few as N+1 measurement cycles. Process and apparatus are disclosed for thus efficiently achieving in vivo NMR relaxometry (including magnetic resonance imaging if desired).

Abstract: Nuclear magnetic resonance well logging apparatus and a method of use for geophysical examination of a bore hole as the bore hole is drilled. The apparatus is connected to the drill bit to follow it through the bore hole as the bore hole is formed. The apparatus comprises a resilient, tubular, permanent magnet for generating a static magnetic field in the region of a portion of the bore hole adjacent the apparatus, which region includes materials sought to be analyzed, an antenna mounted on the magnet and connected to associated circuitry for exciting nuclei of the materials sought to be analyzed in the region, and a receiver connected to the antenna for receiving nuclear magnetic resonance signals from the excited nuclei and for providing an output signal indicative of properties of the materials sought to be analyzed.

Abstract: The fluid transport properties of a porous media are determined by NMR imaging showing the fluid transport properties such as fluid velocity, fluid acceleration, fluid jerk, translational self diffusion, sample permeability to fluid transport, etc.

Abstract: A gradient magnetic field irradiation method comprising irradiating RF pulses and a slice plane selection gradient magnetic field to excite an atomic nucleus of a slice plane, irradiating then first, second and third frequency encoding gradient magnetic fields under the following condition and receiving NMR signals during the irradiation of the third frequency encoding gradient magnetic field:(A) (1/k)-(4/n)+1=0where a ratio of intensity of the first, second and third frequency encoding gradient magnetic field is k:n:1;(B) the irradiation time of the first and second frequency encoding gradient magnetic fields is T/k and 2T/n, respectively, when the irradiation time of the third frequency gradient magnetic field is 2T; and(C) a time interval between the start timing of the irradiation of the first frequency encoding gradient magnetic field and the start timing of the irradiation of the second frequency encoding gradient magnetic field is equal to a time interval between the start timing of the irradiation of

Abstract: A method serves for recording spin resonance spectra of test samples having at least three groups of spins. A first group is coupled to a second group, while a third group is uncoupled relative to the second group but has a spectral position, e.g. chemical shift, which is substantially identical only to that of the first group. For obtaining an isolated image of the signal of the first group, one suppresses the signal of the third group. A pulse sequence of three r.f. pulses (10, 13, 17) are irradiated upon the sample in a manner known as such. The second r.f. pulse (13 ) is applied in such a way that the magnetization of the spins of the first group and of the second group is transferred to a state of double-quantum coherence by coherence transfer. Then, a first magnetic gradient field pulse (15) of a predetermined pulse surface (.epsilon..sub.2), with dephasing effect for the double-quantum coherence, is exerted upon the sample. The third r.f.

Abstract: An actuating drive for controllable adjustment of a plurality of actuators in a nuclear resonance spectrometer is characterized in that the actuating drive has a drive train with a drive shaft (9) that can be driven by an electric drive motor (3) and with a plurality of drive train outputs, for coupling to the actuators, each of which can be individually coupled to the drive shaft by means of a changeover device. This enables the actuators to be adjusted automatically.

Abstract: A non-destructive spoilage detection method of detecting spoilage of a nutritional product having a water activity of at least 0.9 has the steps of: subjecting a nutritional product in a non-metallic sealed container to nuclear magnetic resonance spectroscopy followed by recording the peak free induction decay value associated with an initial nuclear magnetic resonance spectroscopy of the nutritional product. Subsequently the nutritional product is subjected to nuclear magnetic resonance spectroscopy and at least one other peak free induction decay value associated with the nuclear magnetic resonance spectroscopy of the nutritional product is recorded. Over time, at least two of the peak free induction decay values are compared from which a determination is made whether spoilage of the nutritional product is indicated. Preferably subjection of the nutritional product to nuclear magnetic resonance spectroscopy occurs on a regular basis and at approximately the same temperature of the nutritional.

Abstract: A method and an apparatus for predicting the future occurrence of earthquakes continuously measures a physical parameter of the earth's crust by means of magnetic spin resonance measurements to develop an alarm signal. When the value of the alarm signal exceeds a threshold value, an alarm is generated.

Abstract: A method for noninvasively detecting osteoporosis in human subjects by means of NMR imaging is described. In the preferred embodiment, a series of images are acquired whereby the echo time TE is incremented until a predefined number of images, each differing in echo time, has been acquired. The images are then displayed, a region of interest (ROI) is selected and mean signal amplitudes are computed (block 46). The mean signal amplitude values are then used as inputs for the curve fitting procedure that computes T2* (block 48). The final step of the process compares the computed value of T2* with a normal baseline (block 50), which permits the subject to be classified as either normal or osteoporotic (block 52).

Abstract: Methods and apparatus for detecting (and, if desired, imaging) the effects of magnetic resonance in a spin-containing material by measuring the magnetic force acting on a mechanical cantilever having a low damping coefficient due to modulation of the magnetic moment of the material in the polarizing field direction at a frequency substantially lower than the spin resonance frequency. Modulation of the magnetic moment in the direction of the polarizing magnetic field may be achieved by modulating (i) the magnitude of the magnetic field in the polarizing direction or (ii) the frequency or amplitude of a high-frequency magnetic field.

Abstract: A method and an apparatus are disclosed serving to localize proton-poor objects situated in aqueous surroundings, in particular to localize submarines or sea mines in an ocean or an inland water. By using a nuclear magnetic proton resonance technique, a magnetic disturbance caused by the proton-poor object in relation to its proton-rich aqueous surroundings is detected. The apparatus comprises at least one transmission coil for exciting the nuclear resonance by means of an alternating electromagnetic field and comprises detection means for detecting nuclear magnetic resonance signals. The transmission coil generates conditions in the aqueous surroundings in which water proton nuclear magnetic resonance occurs in a volume region of more than 50 cubic meters, preferably considerably more than 1000 cubic meters of water. The volume region is monitored for the presence of nuclear magnetic resonance signals and a predetermined decrease in such resonance signals is detected.

Abstract: There is disclosed a gradient magnetic field coil for use in a magnetic resonance imaging system for imaging an imaginary or virtual cross-section of a desired portion of a subject to be inspected, utilizing a magnetic resonance phenomenon. The gradient magnetic field coil includes a coil bobbin and coil windings fixedly mounted on the coil bobbin. The coil bobbin includes a tubular body portion of a honeycomb construction having a number of vacancies formed in a wall of the tubular body portion, a sheet-like outer peripheral portion of a constrained damping structure fixedly secured to an outer peripheral surface of the body portion to reinforce the body portion, and a sheet-like inner peripheral portion fixedly having at least one layer and secured to an inner peripheral surface of the body portion to reinforce the body portion. The generation and continuation of vibrations in the coil bobbin are controlled or suppressed directly by the coil bobbin itself, thereby minimizing the generation of noise.

Abstract: Use in magnetometry by electronic paramagnetic resonance (EPR) of tetracyanoquinodimethane derivatives in accordance with the formula: ##STR1## in which AH.sup.+ is a cation derived from a heterocyclic aromatic base having at least three aromatic rings and a single NH.sup.+ group included in at least one of the rings, AH.sup.+ being e.g. acridinium or benzoquinolinium.

Abstract: A normal CPMAS experiment is modified to provide for spectral editing. In one embodiment of the invention, the conventional CPMAS experiment is performed with the proton decoupling RF applying at a frequency slightly different than the proton resonance frequency in order to suppress methylene (CH.sub.2) resonances more severely than CH and CH.sub.3 resonances.In another embodiment of the invention the RF pulse sequence normally using during the cross-polarization period is replaced with a WIM RF pulse sequence which has the effect of suppressing the CH and CH.sub.3 resonances, thereby leaving the CH.sub.2 resonances.

Abstract: A detector system for detecting a target material in a sample includes a resonance chamber containing the target for performing magnetic resonance thereon to form dissociated target molecules. A laser is provided for pre-ionizing background material in the resonance chamber and for ionizing the dissociated target molecules. A sensor array detects radiation emitted from the ionized target molecules and a mass spectrometer, which is coupled to the sensor array, analyzes signals from the sensor array to generate a frequency pattern of the target. Electronically stored data tables of known frequency patterns are used for comparing the frequency pattern of the target to the known frequency patterns until a match is determined.

Abstract: In magnetic resonance spectroscopy and imaging, it is usually necessary to obtain spectra only from desired, localized regions of an examination subject. This is accomplished by subjecting the examination subject to a selective radio-frequency (RF) pulse. A method for optimizing the pulse shape of such a radio-frequency pulse includes the steps of exciting a spin system with a frequency-selective radio-frequency pulse, reading out the resulting echo signal, cutting off high-frequency signal components of the echo signal using a filter, and employing the filtered echo signal as the optimized radio-frequency pulse shape.

Abstract: The present invention is directed to biological compounds derivatized so as to contain at least one perfluoro-t-butyl moiety for use in fluorine-19 NMR and/or MRI studies. The perfluoro-t-butyl (PFTB) moiety, ##STR1## is an excellent reporter group for fluorine-19 NMR/MRI. It is a source of nine magnetically equivalent fluorine nuclei which generate a single intense resonance for easy detection in spectroscopy or imaging. This signal is a sharp singlet, not split by neighboring nuclei or spread over a wide frequency range and eliminates any chance of ghost images which might arise from multiple resonances. These spectral properties ensure a maximum signal-to-noise ratio (S/N) for readily detecting this moiety. The foregoing allows either reduction in the concentration of the derivatized compound, ability to use MRI instruments with lower field strengths, a reduction in imaging times, or a combination of the foregoing as a result of this moiety producing a single, sharp, intense resonance.

Abstract: The sensitive detection of explosives and narcotics by nuclear quadrupole resonance (NQR) is performed at low rf power by assuring that the rf field strength is larger than the local magnetic field. Additionally, it has been recognized that signal-to-noise ratio of a signal induced by a specimen of fixed size decreases by only the square root of the coil size. Thus, rather than scaling power linearly with coil size, as conventionally done to maintain the same rf field intensity, the power need only be increased by the square root of the increased coil size to assure maintenance of the same signal to noise ratio. This technique permits the use of larger coils than previously used. The invention is useful for both volume coils and surface coils.

Abstract: A method of determining the proportions of different components of material in a duct comprises exciting nuclear magnetic spins of nuclei of a species common to the components in a region of the duct and utilizing the resulting free induction decay (FID) signal. The nuclear spins are excited simultaneously in the components and the proportions are determined by measuring the phase of the FID signal relative to a phase datum. The method finds particular application for measuring the proportions of oil and water in material obtained from a sub-sea oil well.

Abstract: NMR spectroscopy employing flow-encoding magnetic field gradient pulses provide velocity sensitivity. Spectroscopic analysis of constituents of a sample can be obtained and separated by velocity. Fluid samples to be analyzed are passed through a chromatography column in order to cause different constituents of the sample to pass at different velocities. The sample is then subjected to a velocity sensitive NMR encoding sequence. Data is acquired from the sample which allows a spectroscopic analysis of a constituent of the sample. Signals from molecules of a constituent travelling at a desired velocity can be selectively detected, thereby providing information concerning the molecular weight of the detected molecule. NMR spectra of a mixture of molecules having differing molecular weights and absorption properties can be resolved into their individual constituents.

Abstract: External field compensation is provided for MRI apparatus which is in a magnetically noisy environment such as that caused by nearby subway trains. By means of a magnetometer type sensor, the external field fluctuation is sensed and after being adjusted for the filtering effect of the magnet structure of the MRI device itself, the master oscillator of the MRI device is adjusted to compensate for the external field fluctuation. Alternatively the current of the magnet coil is adjusted.

Abstract: A method for conducting borehole NMR measurements comprising the steps of:providing a magnetic field and a magnetic field gradient at a desired location along a borehole;carrying out at least one NMR experiment in the presence of the magnetic field gradient;sensing the diffusion effect on the decay of at least the first echo; anddetermining therefrom the diffusion coefficient.Apparatus for carrying out the method is also described.

Abstract: The invention relates to an apparatus for measuring chemical and/or physical reaction sequences by nuclear magnetic resonance spectrometry and comprises a reaction path (1), a nuclear magnetic resonance spectrometer (2) and at least one reaction chamber (10) which is located in the reaction path, wherein means are provided for feeding at least the reaction product from the reaction chamber (10) to the nuclear magnetic resonance spectrometer (2). According to the invention, at least reaction chamber (10) and its reagent supply and discharge lines (5 to 7) are mounted, by means of a mounting angle (29), on the same head housing (9) on the latter's end which projects from the spectrometer magnet bore, in the stray field of the spectrometer magnet.

Abstract: Both an antipilferage marker and a system therefor is provided that uses magnetic spin resonance phenomena to generate unique and identifiable signals. The marker generally comprises a substrate which supports a material that generates and identifiable signal as a result of either nuclear magnetic resonance, nuclear quadrupole, electron spin resonance, electron paramagnetic resonance, ferromagnetic resonance, ferrimagnetic resonance, antiferrimagnetic resonance, domain wall resonance or spin wave resonance or spin-echoes. A magnetic material is further provided on the substrate for applying a magnetic field to the resonant material. In the system of the invention, a microwave or radio frequency source emits electromagnetic radiation which is absorbed by the resonant material which in turn reemits electromagnetic radiation having a specific and readily detectable frequency signature.