NL2026338B1

NL2026338B1 - Material analysis method and system

Info

Publication number: NL2026338B1
Application number: NL2026338A
Authority: NL
Inventors: Emmanuel Nemakhavhani Thendo; Nkululeko Hogan Cook Martin; Henry Connell Simon; Ballestrero Sergio; Charles Andrew Richard
Original assignee: Univ Johannesburg
Priority date: 2020-08-25
Filing date: 2020-08-25
Publication date: 2022-04-29

Abstract

The invention relates to methods and systems of analysing material. The method comprises irradiating a target material with photons of a predetermined energy at which giant dipole resonance (GDR) occurs due to photonuclear reactions between the photons and one or more elements present in the target material thereby to activate the target material. Photons of a predetermined energy level emitted from the activated or transmuted target material in a temporal fashion in a detection time interval are detected, wherein a composition of the target material is determined based at least on the photons detected temporally in the detection time interval.

Description

MATERIAL ANALYSIS METHOD AND SYSTEM

FIELD OF THE INVENTION This invention relates, generally, to material analysis methods and systems, particularly, though not necessarily exclusively, to elemental analysis methods and systems.

BACKGROUND OF THE INVENTION Numerous non-destructive material analysis techniques and apparatuses are employed to analyse materials to determine their elemental composition, for example, for the purpose of identifying unknown materials and/or performing a qualitative and/or quantitative analysis thereof without destroying a material sample.

Some techniques, such as those used in coal and mineral industries, exploit interactions between X-ray or gamma-ray photons or neutrons and materials under analysis in order to analyse and characterise materials. One technique is X-ray fluorescence (XRF).

XRF involves irradiating target material with photons from X-ray or gamma-ray sources wherein atoms in the target material absorb these photons and radiate lower energy photons having particular energies which may be used to determine the elemental composition of the material. However, XRF techniques have drawbacks which make them unsuitable for some applications, for example, for low atomic number elements, the energy of the fluorescent photons is very low and can only travel very short distances before being absarbed thus making analysis difficult without additional measures being taken and/or analysis being undertaken within very limited parameters.

The Inventors are aware of uses of x-ray and/or gamma ray photons which are used to irradiate a target material to determine the elemental composition thereof based on Compton profile analysis of scattered photons. However, these applications require well defined detection geometries to avoid kinematic broadening. Well defined detection geometries are often realised by limiting flux received to a particular path/s by collimation.

This has a drawback of having limited applications in analysing material, because collimation restricts the analysis to a very small sample.

Prompt Gamma-ray neutron activation analysis (GAA), or variants thereof, is another technique used for analysing material to determine a quantitative and/or qualitative elemental composition thereof. In this technique, a sample of target material is irradiated with neutrons from a neutron source, constituent elements of the sample absorb some of these neutrons and emit gamma rays which are measured by a suitable gamma ray spectrometer wherein energies of measured gamma rays identify the elements whereas intensities of peaks at these energies are markers of the elemental concentration. A practical drawback with these GAA techniques is that neutron activation induces significant radioactivity in most materials thus presenting health and safety concerns which require frequent decontamination. Moreover, adequate radioactive shielding measures have to be put in place in order to use these techniques thus resulting in a costly approach to analysing material. GAA is limited in its ability to detect low Z elements, so it is not a good technique to investigate elements with a relatively low atomic number or low Z elements.

Fast neutron scattering in well-defined kinematic geometries are also proposed. But here the neutron collimation is flux limiting and inefficient, and there are also radiological concerns.

Positron Emission Tomography (PET) is a technique used to construct a three- dimensional density image of a positron emitting isotope. PET has historically been used in the medical field as a diagnostic or research tool. However, the application of PET has been extended to the mineral processing industry with the remote detection of diamonds within their host kimberlite rock, termed Mineral-PET (“MIinPET”, for brevity).

In MinPET, carbon within diamonds is activated via bremsstrahlung produced by an accelerated electron beam, and a high enough signal to noise ratio is obtained by a detection system to discern diamonds within kimberlite on an industrial scale in an online/real-time fashion typically onsite at a mine as the kimberlite is transported on a suitable conveyor. Due to the volume of material being processed, the detection system is fast and diamonds or diamondiferous material are detected and sorted almost instantaneously as they move through a detector arrangement.

Due to the nature of the online/real-time detection of diamonds and/or diamondiferous material at the site of a mine, MinPET is not concerned with the composition of a target material but only whether or not diamonds and diamondiferous material is present in Kimberlite rock.

More nuclear analysis techniques are known in the art but they often have drawbacks associated therewith including some being confined to the laboratory with limited application in an online fashion.

In view of the foregoing, the Inventors believe that it is desirous to provide a material analysis technique which addresses some of the drawbacks associated with conventional material analysis techniques and/or providing an alternative technique for analysing a material.

SUMMARY OF THE INVENTION According to a first aspect of the invention, there is provided a method of analysing material, wherein the method comprises: irradiating a target material with photons having an energy within a predetermined energy range at which a giant dipole resonance (GDR) occurs so as to activate or transmute the target material due to photonuclear reactions between the photons and one or more elements present in the target material; detecting photons of a predetermined energy level emitted from the activated or transmuted material as a result of positron annihilation in the activated or transmuted material, wherein the photons are detected in a temporal fashion in a detection time interval after irradiation; and determining a composition of the target material based at least on the photons detected temporally in the detection time interval.

The method may comprise identifying the target material based on the determined composition thereof. For example, the method may be configured to identify the material as being explosives, narcotics, meat with a particular amount of marbling, etc. based on the determined composition. Moreover, the method may comprise determining one or more characteristics of the material analysed, for example, as is the case of the coal analysis system disclosed herein which is configured to determine one or more characteristics of material in the form of coal. As will be understood from the disclosure herein, determining the composition of the material may comprise determining all or part of the composition of the material.

In any event, it will be noted that the method may comprise detecting photons in the detection time interval, a predetermined time after irradiating the target material. The step of irradiation may precede the step of detection as is well understood.

The step of determining the composition of the target material may comprise determining an elemental composition of the target material. The step of determining the elemental composition of the target material may comprise identifying one or more/two or more elements present in the target material based on photons emitted by one or more associated positron emitting isotopes in the activated or transmuted target material during the detection time interval. The step of determining the elemental composition of the target material may also comprise determining concentration/s of one or more elements/two or more elements present in the target material based on photons emitted by one or more associated positron emitting isotopes in the activated or transmuted target material during the detection time interval.

The activation or transmutation/irradiation may be to activate two or more elements in the target material due to the photonuclear reactions between the bremsstrahlung photons and two or more elements in the target material.

The step of determining the composition of the target material may comprise identifying a type of molecule in the target material by correlating the determined elemental composition to known molecule elemental compositions.

The step of identifying at least one type of molecule present in the target material may be preceded by the step of determining one or more elements present in the target material wherein each molecule has distinctive elemental composition.

The activated or transmuted material may comprise one or more positron emitting isotopes corresponding to one or more elements present in the target material. Each positron emitting isotope in the activated or transmuted target material may have a different temporal decay profile and the rate at which each positron emitting isotope decays and emits positrons depends on its characteristic half-life or life-time. 5 The method may comprise identifying an element based on the photons detected in the detection time period and the temporal decay profiles of the positron emitting isotopes. The detected photons emitted from the activated or transmuted target material may be as a result of positron annihilation due to irradiation of the target material with photons having an energy within the range at which a GDR occurs.

The method may comprise detecting one or both of back-to-back co-linear and co-incident gamma ray photons of a predetermined energy level emitted from the activated or transmuted target material during the detection time interval.

The photons detected may be annihilation photons described herein which may have an energy level of approximately 511 keV. In some example embodiments, the method comprises rejecting photons not having the energy level of approximately 511 keV.

The method may comprise generating a reconstructed a 3D tomographic image or tomogram based on the photons detected in the detection time interval, wherein the reconstructed 3D tomographic image or tomogram is indicative or illustrative of the composition of the target material.

The method may comprise generating a 2D image based on the photons detected in the detection time interval, wherein the reconstructed 2D image is illustrative of composition of the target material.

The method may comprise detecting photons emitted by way of a suitable detector arrangement; and determining the composition of the target material by one or more processors communicatively coupled to the detector arrangement to receive detector data therefrom indicative of the photons detected in the detection time interval.

The method may comprise detecting photons in a time differential fashion over the detection time interval, wherein the processor is configured to process the detector data received over the detection time interval in a series of successive time slices in order to determine the composition of the target material. The detector data may comprise detection signals, or data indicative thereof, having energy level peaks at approximately 511 keV. The energy level peaks may be provided at different times within the detection time interval. The raw detector data from the detector arrangement may be binned in the manner described herein and the term “detector data” used herein may refer to data associated with the detection of annihilation photons in varying degrees of abstraction from low level raw signal data from the detector arrangement to processed data, for example, the detector data is used broadly to also refer to the actual data detected by the detector arrangement as well as the higher level histogrammed time slices according to energy as described herein. These variations will be evident to those skilled in the art whom will appreciate that though the level of abstraction defined herein is implementation specific, it should not detract from the broader disclosure herein.

The method may comprise decomposing the detector data comprising detection signals into a plurality of exponential components in order to determine relative concentrations of elements in the composition of the target material.

The method may comprise determining the composition of the material by comparing the detector data to pre-determined detector data associated with various materials.

The method may comprises holding the activated or transmuted target material and the detector arrangement in an operatively fixed relation relative to each other for a time at least equal or more that the detection time interval and simultaneously detecting photons emitted from the activated or transmuted target material during the course of the detection time interval.

The method may comprise receiving prior data indicative of an elemental composition of one or more elements present in the target material in order to determine the composition of the target material.

The detection time interval may be is a non-instantaneous predetermined time period.

The detection time interval may be associated with a decay time constant of at least one positron emitting isotope corresponding to at least one element in the target material. In particular, the detection time interval may be selected from between one third of the decay time constant to three times the decay time constant of at least one positron emitting isotope in the activated or transmuted target material. In one example embodiment of the invention, the method comprises time-stamping photons detected in the detection time interval. In particular, the method may comprise storing or binning detector data (described in more detail below) associated with the detected photons in the detection time interval in time slices in a memory device. The method may comprise generating a plurality of histograms of each time slice binned according to the energy of the photons detected. In other words, the method may comprise histogramming each time slice of detector data received (and stored or binned) in the detector time interval according to energy. This may be an average energy of the detected photons over the time slice, as well as an average photon count over the time slice, as the case may be.

For each histogram, the method may comprise implementing an annihilation energy range or window around 511 keV, and fitting the shape of the histogram within this window by a function with two components, a first of which may be photon hit count, and a second of which may be the size of the 511 keV energy peak above the background photon hit count. The 511 keV peak size from each of these fits gives one data point.

The method may comprise taking all of the data points from all of the time slices and plotting them against their weighted average time. In this way, a resultant graph shows the decay profile. The decay profile graph may be fitted as a sum of exponential decays to extract the relative concentrations of isotopes that are present the material M as described herein.

According to another aspect of the invention, there is provided a system for analysing material, wherein the system comprises:

an irradiator configured to irradiate a target material with photons having an energy within a predetermined energy range at which a giant dipole resonance (GDR) occurs so as to activate or transmute the target material due to photonuclear reactions between the photons and one or more elements present in the target material; a detector arrangement defining a detection zone configured to detect photons of a predetermined energy level emitted from the activated or transmuted target material located in the detection zone as a result of positron annihilation in the activated or transmuted target material, wherein the photons are detected in a temporal fashion in a detection time interval after irradiation; a memory device storing data; and at least one processor communicatively coupled to the detector arrangement and the memory storage device, wherein the one or more processors is/are configured to determine a composition of the target material based at least on detector data from the detector arrangement indicative of the photons detected temporally in the detection time interval by the detector arrangement.

The system may be configured to hold the activated or transmuted target material and the detector arrangement in an operatively fixed relation relative to each other such that the activated or transmuted target material is located in the detection zone for a time at least equal or more that the detection time interval and simultaneously detecting photons emitted from the activated or transmuted target material during the course of the detection time interval.

The at least one processor may be configured to determine the composition of the target material by determining an elemental composition of the target material.

The elemental composition of the target material may be determined by identifying one or more elements present in the target material in particular concentrations based on photons emitted by associated one or more positron emitting isotopes in the activated or transmuted target material during the detection time interval.

The at least one processor may be configured to determine all or part of the composition of the target material by identifying a type of molecule in the target material by correlating the determined elemental composition to known molecule elemental compositions.

The activated or transmuted target material may comprise one or more positron emitting isotopes corresponding to one or more elements present in the target material. Each positron emitting isotope in the activated or transmuted target material may have a different temporal decay profile and may emit photons at different times in the detection time interval.

The at least one processor may be configured to identify an element based on the photons detected in the detection time period and the temporal decay profiles of the positron emitting isotopes.

The detector arrangement may be configured to detect one or both of back-to-back co-linear and co-incident gamma ray photons of a predetermined energy level emitted from the activated or transmuted target material during the detection time interval. The detector data may comprise at least time-stamped energy data associated with the photon detected by the detector arrangement.

The detector arrangement may be configured to detect photons having an energy level of approximately 511 keV. Detecting photons having an energy level of approximately 511 keV may comprise detection photons having an energy level within a window around 511 keV.

The detector arrangement may be configured to detect back-to-back co-linear and co-incident gamma ray photons along a line of response (LoR), wherein the detector data comprises a plurality of lines of response, or information indicative thereof.

The detector arrangement may comprise one or more detectors or detector arrays comprising a plurality of detectors each having sensing axes intersecting with the detection zone.

The detector arrangement may be configured to generate a plurality of LoRs which correspond to imaginary lines through the activated or transmuted target material connecting strikes on the detectors on opposite sides of the activated or transmuted target material, wherein the strikes correspond to the back-to-back co-linear and co-incident gamma ray photons emitted by the activated or transmuted target material as detected by the detector arrangement.

The at least one processor may be configured to generate a reconstructed a 3D tomographic image or tomogram based on the photons detected in the detection time interval, wherein the reconstructed 3D tomographic image or tomogram is illustrative of the composition of the target material.

The at least one processor may be configured to generate a 2D image based on the photons detected in the detection time interval, wherein the reconstructed 2D image is illustrative of composition of the target material.

The detector arrangement may be configured to detect photons in a time differential fashion over the detection time interval, wherein the at least one processor is configured to process the detector data received over the detection time interval in a series of successive time slices in order to determine the composition of the target material.

The detector data may comprise detection signals, or data indictive thereof, having energy level peaks at approximately 511 keV provided at different times within the detection time interval.

The at least one processor may be configured to decompose the detector data comprising detection signals into a plurality of exponential components in order to determine relative concentrations of elements in the composition of the target material.

The at least one processor may be configured to determine the composition of the material by comparing the detector data to pre-determined detector data associated with various materials.

The at least one processor may be configured to receive prior data indicative of an elemental composition of one or more elements present in the target material in order to determine the composition of the target material.

According to another aspect of the invention, there is provided a non-transitory computer readable medium storing a non-transitory set of instructions which when executed by one of more processors cause the one or more processors to: receive detector data from a detector arrangement associated with photons of a predetermined energy level detected by a detector arrangement in a temporal fashion in a detection time interval from an activated or transmuted target material which emits photons due to positron annihilation; and process the detector data to determine a composition of the target material based at least on detector data from the detector arrangement indicative of the photons detected temporally in the detection time interval by the detector arrangement.

According to another aspect of the invention, there is provided a method of analysing a target material, wherein the method comprises: receiving detector data from a detector arrangement associated with photons of a predetermined energy level detected by a detector arrangement in a temporal fashion in a detection time interval from an activated or transmuted target material which emits photons due to positron annihilation; and processing the detector data to determine a composition of the target material based at least on detector data from the detector arrangement indicative of the photons detected temporally in the detection time interval by the detector arrangement.

According to yet another aspect of the invention, there is provided a system for analysing material, wherein the system comprises: a memory device storing data; and at least one processor communicatively coupled to the memory device, wherein the at least one processor is configured to: receive detector data from a detector arrangement associated with photons of a predetermined energy level detected by a detector arrangement in a temporal fashion in a detection time interval from an activated or transmuted target material which emits photons due to positron annihilation; and process the detector data to determine a composition of the target material based at least on detector data from the detector arrangement indicative of the photons detected temporally in the detection time interval by the detector arrangement.

The activated or transmuted target material may be the target material which has been activated or transmuted by irradiation with photons of a predetermined energy range at which giant dipole resonance (GDR) occurs due to photonuclear reactions between the photons and one or more elements present in a target material. The term “temporally” may be understood to include the meaning of the words “sequentially”, “chronologically” within the detection time interval.

According to another aspect of the invention, there is provided a method of analysing material, wherein the method comprises: irradiating a target material with photons of a predetermined energy range at which a giant dipole resonance (GDR) occurs; detecting photons of a predetermined energy emitted from the irradiated material as a result of positron annihilations in the irradiated material in a temporal fashion in a detection time interval; and determining a composition of the target material based at least on the photons detected temporally in the detection time interval.

The positron emissions may be as a result of nuclear, particularly photonuclear, reactions in the irradiated material. The irradiated material may be an umbrella term to describe the activated or transmuted target material as contemplated herein.

Moreover, the step of “detecting photons of a predetermined energy” as described herein may be understood to mean detecting photons having a predetermined energy. Moreover, the predetermined energy may be around a particular energy value or may be a predetermined energy range. For example, the phrase “detecting photons of a predetermined energy” may be understood to include detecting photons having an energy at or around 511 keV or detecting photons having energy within an energy range which encompasses 511 keV.

It will be appreciated that the term “material” is used herein in a broad sense in that itmay refer to one or more objects including one of more particles of unspecified dimensions of different compositions. Moreover, the term target material may be the material to be analysed or required to be analysed. In this regard, the target material may be a single object or multiple object/s.

Moreover, the term target material may be understood to be a majority of the material under analysis, for example, in the analysis of coal, impurities may be present but the target material may be coal.

The target material may comprise one element or it may comprise a plurality of molecules each having a different elemental composition.

In some example embodiments, the target material may thus be any material which is irradiated in a manner disclosed herein.

However, in some example embodiments, the target material may refer to the actual material sought to be irradiated.

Moreover, the step of determining a composition of the target material as described herein may be understood to be determining all or part of the composition of the target material.

In addition this step may be understood as the step of identifying one or more elements in the target sample.

According to another aspect of the invention, there is provided a system for analysing material, wherein the system comprises: an irradiator configured to irradiate a target material with photons of a predetermined energy range at which a giant dipole resonance (GDR) occurs; a detector arrangement defining a detection zone configured to detect photons of a predetermined energy level emitted from the irradiated material in a temporal fashion in a detection time interval due to positron emissions in the irradiated material located in the detection zone; a memory device storing data; and at least one processor communicatively coupled to the detector arrangement and the memory storage device, wherein the one or more processors is/are configured to determine a composition of the target material based at least on detector data from the detector arrangement, wherein the detector data is indicative of the photons detected temporally in the detection time interval by the detector arrangement.

According to yet another aspect of the invention, there is provided a computer readable medium storing a non-transitory set of instructions which when executed by one of more processors cause the one or more processors to:

receive detector data from a detector arrangement associated with photons of a predetermined energy detected by the detector arrangement in a temporal fashion in a detection time interval due to positron emissions from a target material irradiated, during a preceding irradiation step, with photons of a predetermined energy range at which a giant dipole resonance (GDR) occurs; and process the detector data to determine a composition of the target material based at least on detector data from the detector arrangement indicative of the photons detected temporally in the detection time interval by the detector arrangement.

According to another aspect of the invention, there is provided a method of analysing a material, wherein the method comprises: irradiating the material with photons of a predetermined energy at which a giant dipole resonance (GDR) occurs; detecting photons of a predetermined energy level emitted sequentially from the irradiated material within a predefined time period due to positron annihilation in the irradiated material, and identifying one or more elements associated with the sequentially emitted photons detected in the predetermined time period.

According to another aspect of the invention, there is provided a system for analysing a material, wherein the system comprises: an optional irradiator for irradiating the material with photons of a predetermined energy at which a giant dipole resonance (GDR) occurs; an optional detector arrangement configured to detect photons of a predetermined energy level emitted sequentially from the irradiated material within a predefined time period due to positron annihilation in the irradiated material, a memory device storing data; and at least one processor communicatively coupled to the detector arrangement and the memory device, wherein the at least one processor is configured to identifying one or more elements associated with the sequentially emitted photons detected in the predetermined time period.

According to another aspect of the invention, there is provided a method of analysing coal, wherein the method comprises: irradiating a sample of coal with photons of a predetermined energy at which giant dipole resonance (GDR) occurs to form positron emitting isotopes of one or both of oxygen and carbon in the sample of coal due to photonuclear reactions between the photons and oxygen and/or carbon in the sample of coal; detecting photons of a predetermined energy level emitted sequentially from the irradiated sample of coal in a predetermined time period due to positron annihilation in the irradiated sample of coal, and determining a composition of the sample of coal based at least on the photons detected temporally in the detection time interval, wherein a determined composition of oxygen in the sample of coal is representative of the moisture content of the sample of coal, and/or wherein a determined composition of carbon in the sample of coal is representative of the calorific content of the sample of coal.

According to another aspect of the invention, there is provided a method of analysing coal, wherein the method comprises: irradiating a sample of coal with photons of a predetermined energy at which giant dipole resonance (GDR) occurs; detecting photons of a predetermined energy level emitted sequentially from the irradiated sample of coal in a detection time interval; and determining one or both of a moisture content and calorific value of the sample of sample of coal, or approximations thereof, based on the sequentially emitted photons detected in the detection time interval. According to another aspect of the invention, there is provided a method of detecting landmines below a surface, wherein the method comprises: irradiating a sample of ground with photons of a predetermined energy at which giant dipole resonance (GDR) occurs; detecting photons of a predetermined energy level emitted temporally from the irradiated sample of ground in a detection time interval, and determining the composition of the sample of ground to contain one or more explosives based on the sequentially emitted photons detected temporally in the predetermined time interval.

According to another aspect of the invention, there is provided a method of determining characteristics of a material by determining an elemental composition thereof in a manner described herein; and using the determined elemental composition as a proxy for one or more characteristics of the material.

It will be understood by those skilled in the art that the comments which are provided above with respect to each aspect of the invention may be applied mutatis mutandis to other aspects of the invention. Moreover, it will be understood that reference to a specific aspect of the invention relating to a method may be understood to also include by reference a suitable system having a memory device and processor configured to perform the method, or parts thereof, or the like. Similar considerations apply to a non-transitory computer readable medium storing a set non-transitory computer executable instructions which when performed by a suitable computer causes the same to perform any of the methodologies described herein, or part thereof as will be appreciated by those skilled in the art.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows a high-level conceptual diagram of a material analysis system in accordance with an example embodiment of the invention; Figure 2 (a)-(c) show high-level conceptual diagrams of detector arrangements in accordance with example embodiments of the invention; Figure 3 shows a high-level conceptual diagram of material analysis system in the form of a coal analysis system employed in a coal handling site such as at a coal mine or a coal fired power plant according to an embodiment of the invention; Figure 4 shows a conceptual diagram of a coal analysis system of Figure 3 in more detail; Figure 5 shows an illustrative diagram of material analysis system in the form of a land mine detection system according to an embodiment of the invention;

Figure 6 show a graph of a time differential signal acquisition of positron emitting isotope (PET isotope) emissions over a period of time leading to a PET gamma ray spectroscopic line at 511 keV as a time sequence of signals, getting weaker in time; Figure 7 shows a graph of a time spectrum of PET isotope signal strength; Figure 8 shows graphs of various compounds graphed according to carbon, oxygen, and nitrogen as a fraction of the total number of atoms; Figure 9 shows a high-level block flow diagram of a method in accordance with an embodiment of the invention; Figure 10 shows a block flow diagram of a method in accordance with an embodiment of the invention; Figure 11 shows another block flow diagram of a method in accordance with an embodiment of the invention; and Figure 12 shows a diagrammatic representation of a machine in the example form of a computer system in which a set of instructions for causing the machine to perform any one or more of the methodologies discussed herein, may be executed.

DETAILED DESCRIPTION WITH REFERENCE TO THE DRAWINGS The following description of the invention is provided as an enabling teaching of the invention. Those skilled in the relevant art will recognise that many changes can be made to the embodiments described, while still attaining the beneficial results of the present invention. It will also be apparent that some of the desired benefits of the present invention can be attained by selecting some of the features of the present invention without utilising other features.

Accordingly, those skilled in the art will recognise that modifications and adaptations to the present invention are possible, and may even be desirable in certain circumstances, and are a part of the present invention. Thus, the following description is provided as illustrative of the principles of the present invention and not a limitation thereof.

It will be appreciated that the phrase “for example,” “such as”, and variants thereof describe non-limiting embodiments of the presently disclosed subject matter. Reference in the specification to “one example embodiment”, “another example embodiment”, “some example embodiment”, or variants thereof means that a particular feature, structure or characteristic described in connection with the embodiment(s) is included in at least one embodiment of the presently disclosed subject matter. Thus, the use of the phrase “one example embodiment”, “another example embodiment”, “some example embodiment”, or variants thereof does not necessarily refer to the same embodiment(s).

Unless otherwise stated, some features of the subject matter described herein, which are, described in the context of separate embodiments for purposes of clarity, may also be provided in combination in a single embodiment. Similarly, various features of the subject matter disclosed herein which are described in the context of a single embodiment may also be provided separately or in any suitable sub-combination.

The headings used herein are for organizational purposes only and are not meant to be used to limit the scope of the description or the claims. For brevity, the word “may” is used in a permissive sense (ie. meaning “having the potential to”), rather than the mandatory sense (i.e., meaning “must”).

The words “include,” “including,” and “includes” and the words “comprises”, “comprising”, and “comprises” mean including and comprising, but not limited thereto, respectively. Additionally, as used herein, the term “coupled” may refer to two or more components connected together, whether that connection is permanent (e.g., welded, cast, moulded, carved) or temporary (e.g., bolted, screwed, adhered via an adhesive), direct or indirect (i.e., through an intermediary), mechanical, chemical, optical, or electrical as is the case in a communicatively coupled components which may be in communication with each other wirelessly or in a hardwired fashion.

Referring to Figure 1 of the drawings, an example of a material analysis system in accordance with an example embodiment of the invention is generally indicated by reference numeral 10.

The system 10 is typically for analysing a target material or sample of target material M so as to determine a composition thereof, wherein determining the composition of the target material may include determining all or part of the composition of the target material. To this end, the system 10 is configured to perform a low-level elemental analysis of the material M to determine an elemental composition of the material M. The material M may be composed of one or more elements in a particular ratio. Moreover, the elements present in the material may typically be elements with low atomic numbers or Z numbers, for example, oxygen, carbon, and nitrogen.

Moreover, the system 10 is configured to perform a higher-level molecular analysis of the material M which may or may not be based on the low-level elemental analysis. Notwithstanding, the principles of operation of the system 10 is the same as will be evident from the disclosure herein.

The system 10 is a high-level analysis system which may find application across a range of industries, for example, mineral processing industries, food and beverage industries, as well as defence and security industries. In this regard, the system 10 may be located at worksites such as at a site of a mine, power plant, food factory, minefield, or the like where the material M to be analysed. This may be achieved in an online fashion and in real-time or substantially real-time. Alternately, parts of the system 10 may be located at the aforementioned worksites.

The system 10 comprises a suitable irradiator 12, a detector arrangement 14, a memory device 18, and a processor 16.

The irradiator 12 is configured to emit or irradiate photons, particularly those photons at a predetermined energy or predetermined energy range or band at which a giant dipole resonance (GDR) occurs. In some example embodiments, this may be in addition to photons of other energies outside of the predetermined energy range or band.

In particular, the irradiator 12 is configured to generate and irradiate the material M with said generated photons so as to activate or transmute the material by creating or forming or generating one or more positron emitting isotopes in the material M from so- called parent elements present in the material M due to a nuclear reaction, particularly a photonuclear reaction, between the photons emitted by the irradiator 12 and one or more elements in the material M. In irradiating the material M, the irradiator 12 is configured to direct the photons created or generated by the irradiator 12 towards the target material M. To this end, the irradiator 12 may define an irradiation zone which photons generated or created or formed by the irradiator 12 may irradiate.

For brevity, the terms “created” or “generated” or “formed” used in the context of the present disclosure with respect to photons may be understood in its broadest sense to include resultant emission of photons from nuclear and/or photonuclear reactions, as is understood in the field of invention. In addition, the terms “activate” and “transmute”, as well as their associated terms, may be understood to refer to the nuclear, particularly photonuclear process/es which result in the creation and/or formation and/or generation and/or activation and/or transmutation of one or more positron emitting isotopes from one or more so-called parent elements as is also understood in the field of invention. It follows that the activated or transmuted target material M may therefore be understood to mean the target material comprising one or more positron emitting isotopes. Collectively, the activated or transmuted material target may be referred to as the “irradiated material” which may comprise one or more positron emitting isotopes.

Irradiation by the irradiator 12 is usually democratic and thus in multi-element materials, there is strong chance that multiple positron emitting isotopes are formed in the activated or transmuted target material M by the irradiation from the irradiator 12. In this way, one or more positron emitting isotopes or positron emitting tomography isotopes, both referred to herein as PET isotopes, are formed in the activated or transmuted target material M.

In one example embodiment, the irradiator 12 comprises an electron accelerator {not shown) configured to produce electrons having an energy of about 40 MeV, or more, for example 100 MeV as well as a high Z material, wherein electron accelerator is configured to direct electrons to impact on the high Z material to create bremsstrahlung photons capable of activating or transmuting the material M being analysed. For brevity, it may be therefore said that the irradiator 12 activates or transmutes the target material M by forming or creating or generating one or more positron emitting isotopes therein due to the photonuclear reaction mentioned herein.

The electron accelerator may be selected from a group comprising a linac, betratron, racetrack microtron, or the like to generate high energy electrons of at or around 40 MeV or more. The high Z number element may be any element with a high atomic number, for example, tungsten.

The photons from the irradiator 12 which irradiate the material M may be in the form of gamma ray beams from bremsstrahlung. In particular, it will be understood that the electron accelerator of the irradiator 12 may be configured to generate electrons at or around 40 MeV to 100 MeV or more to impinge on the high Z element material in the irradiator 12 to yield bremsstrahlung photons which have lower energy that is spread across a broad spectrum. The photons which are relevant to the invention disclosed herein are at a Giant Dipole Resonance. Moreover, these photons have an energy of roughly between 20 - 27 MeV, inclusive.

It will be noted that though higher energy electron accelerators, for example, those capable of generating electrons of 100 MeV may be employed herein, these accelerators are usually costly and are relatively inefficient for the purpose disclosed herein. It follows that it is preferable that the electron accelerator of the irradiator 12 generates electrons of at least 40 MeV to impinge upon the high Z element to yield 20 - 27 MeV bremsstrahlung photons as mentioned above. Instead, or in addition, these photons may be from inverse Compton/Thompson scattering, a plasma wake field device or some type of undulator radiation, or the like.

In the context of this specification, the terms “bremsstrahlung photons” may be used interchangeably with the terms “irradiation photons”, “irradiated photons”, “gamma rays”, “gamma ray photons”, etc. as the photons emitted by the irradiator 12.

For ease of explanation, reference to the target material and activated or transmuted target material will be made with the same reference M but it will be appreciated but those skilled in the art will understand that the target material M prior to activation or transmutation and after activation or transmutation is different in that after activation and transmutation, the activated or transmuted material M comprises positron emitting isotopes. Also herein, the activated or transmuted material may be referred to as the “irradiated material”.

In any event, it will be appreciated that almost all beta plus (B+) decays of positron emitting isotopes create positrons which thermalise before annihilating with an electron to result, most often, in a pair of gamma ray photons of 511 keV being emitted. The terms “gamma ray photons of 511 keV”, “annihilation photons”, “511 keV photons”, “511 keV gamma ray photons”, “511 keV pair” or “511 keV gamma rays” may all, as they suggest,

refer to the back-to-back co-linear and co-incident photons emitted from the material due to the annihilation of positrons emitted by one or more positron emitting isotopes in the activated or transmuted material M (due to B+ decay) and electrons and thus these terms may be used interchangeably herein.

Positron emitting isotopes cannot be distinguished one from another by the photon energy as all so-called annihilation photons have substantially the same energy of approximately 511 keV as mentioned above. However, each PET isotope has its own characteristic life-time/half-life and/or a temporal decay signature over a period of time and this is how one PET isotope is distinguishable from another and, by proxy, their corresponding parent elements are also distinguishable from one another and it is this feature which the systems and methods disclosed herein exploit to be able to determine the composition of the target material M as disclosed herein.

In this regard, referring also to Figure 2 of the drawings, the system 10 comprises a detector arrangement 14 which is configured to detect one photon or both photons of a pair of gamma ray photons of 511 keV emitted from the activated or transmuted material M due to positron annihilation in a temporal fashion over a detector time interval or period. The terms “interval”, “period” and “window” may be used interchangeably herein to refer to a particular timeframe in which the annihilation photons emitted from the activated or transmuted material are detected. Moreover, it will be noted that the activated or transmuted material M may emit annihilation photons in a temporal fashion in the detection time interval depending on the positron emitting isotope/s present in the activated or transmuted material M.

Though some aspects of the invention described herein, particularly the functional aspects, may be broadly described from a conceptual or functional perspective, it will be understood by those skilled in the art that the low level technical details and variations to achieve the desired conceptual functionality may be varied and may be realised in various ways. Where aspects of the present disclosure are described conceptually, it will be understood by those in the art that these may be achieve in various ways and conversely where low level technical details are provided, they are not intended to limit the scope of the disclosure but are provided for completeness by way of example.

For example, it will be appreciated by those skilled in the art that in detecting photons emitted from the activated or transmuted material M temporally in the detection time interval, the detector arrangement 14 may generate or may be used to generate detector data which is indicative of 511 keV photons detected by the detector arrangement 14 as well as the time in the detector time interval or period at which the 511 keV photons were detected. It follows that the detector data may therefore be in the form of or may comprise at the minimum time-stamped energy data indicative of the annihilation photons detected temporally in the detection time interval. The detector arrangement 14 and/or the processor 20 may be configured to time-stamp annihilation photons detected in the detection time interval to generate the time-stamped energy data associated with the detected annihilation photons.

In some example embodiments, the time stamped energy data may be binned or form a histogram representative of a decay profile/signature/pattern of the sample over the detection time interval. It will be understood that the different time dependent shapes of the PET intensities contains the information of the identity and/or composition of the different decay life-time components of the positron emitting isotopes present in the activated or transmuted material M.

Instead, or in addition, the detector data may be high level data which may be in a predetermined data structure as opposed to being raw signal data, which may be the case in some example embodiments.

The annihilation photons having an energy of approximately 511 keV, may be well understood to be a result of positrons annihilating with electrons in the activated or transmuted material M.

The detector arrangement 14 is typically located downstream from the irradiator 12. In some example embodiments, there may be a suitable conveyor system to convey the activated or transmuted material M from the irradiator to the detector arrangement 14.

The arrangement 14 may define a detection zone D within which the activated or transmuted material M is locatable. The detector arrangement 14 may comprise one or more detector arrays, wherein each array comprises a plurality of detectors in the form of scintillator crystals and/or photomultiplier tube (PMT) detectors with suitable electronics.

The PMTs could be their modern equivalent, the silicon photomultiplier or Si-PM.

In some example embodiments, the detectors could also be gas-based ionisation detectors, in a suitable arrangement.

Instead, or in addition, the detectors could be any other light, particularly photon, sensitive detector.

For example, the detectors could be based on the avalanche photo diode mechanism as readout of the scintillation light, or any other such technology.

The phrase “detector hits” may be understood to mean 511 keV photons incident on the detectors of the detector arrangement 14 as detected thereby.

A benefit of the disclosure herein is the functionality of the system 10 to image the determined composition of the target material M.

In this regard, the determined composition may be just one or two elements determined to be in the material and not necessarily all the elements present in the material.

In Figure 2, particularly Figure 2(a), a conceptual diagram of a detector arrangement 14(a) is illustrated.

The arrangement 14(a) is arranged around the detection zone D so as to detect the back-to-back co-linear and co-incident annihilation photons along lines of response (LoRs) emitted from the target material M, in use, as will be described below.

The detector arrangement 14(a) is typically a ring-like or cylindrical arrangement but other configurations may be realised to detect a pair of annihilation photons in coincidence, in use.

The arrangement 14(a) may be configured to detect a spatial position of coincident detections along LoRs, signal strength (which may be a feature of the detector to detect in any event), as well as the time in which the pair of coincident photons LoRs are received, the last two may be in the form of time-stamped energy data indicative of the energy of the photons detected and the time in which it was detected in the detection time interval as described above.

The arrangement 14(a) is configured to generate or facilitate generation of detector data comprising the aforementioned detected data (LORs with theta, phi, x1, y1, E, t), wherein the detector data associated with the pairs of annihilation photons detected by the detector arrangement 14(a) may comprise sinograms of LoRs which may be binned and processed to a 3D tomogram of PET isotope distribution in a conventional fashion.

It follows here that the detector data may therefore comprise spatial data associated with the photon hits on the detector arrangement 14 as well as the time-stamped energy data of the detected photons as represented in a 3D tomogram or as from which a 3D tomogram can be assembled or reconstructed.

In Figure 2(b) a conceptual illustration of another detector arrangement 14(b) in accordance with an example embodiment of the invention which is configured to detect only one of the pair of annihilation photons is shown.

The detector arrangement 14(b) may thus be a planar arrangement which may disregard one of the 511 keV photons in the 511 keV pairs and collects only single hits.

The arrangement 14(b} may comprise one or more apertures (not shown), for example, a pinhole and may be configured to collect reduced spatial data of detector detections (than the arrangement 14(a) which detects both 511 keV coincident photons), signal strength (which may be a feature of the detector to detect in any event), as well as the time in which the detector hit occurred in the detector time interval.

The arrangement 14(b) is configured to generate or facilitate generation of detector data comprising the aforementioned detected data (x, y, E, t), wherein the detector data associated with the single annihilation photons detected by the arrangement 14(b) may be used to generate a 2D or even 3D image of the PET isotope distribution in the activated or transmuted material in a conventional fashion.

In 2D, this may be equivalent to a so-called gamma camera used to image gamma rays.

Here also, the detector data may comprise spatial data associated with the photon hits on the detector arrangement 14 as well as the time-stamped energy data of the detected photons which may be represented in a 3D PET image.

This methodology may be referred to as SPECT.

In Figure 2(c) a conceptual drawing of another detector arrangement 14(c) which is configured to detect only one of the pair of annihilation photons is illustrated.

The detector arrangement 14(c) is similar to that of 14(b) in that it disregards one of the 511 keV photons in the 511 keV pairs and collects only single hits.

However, the arrangement 14(c) does not collect spatial data of detector detections but only signal strength, as well as the time in which the detector hit occurred in the detector time interval.

The arrangement 14(c) cannot form images but as there is no spatial resolution{1D) and thus the arrangement 14(c) may use the energy signals of the photons detected to select for 511 keV radiation thereby reducing noise due to non-positron annihilation events.

It follows here that the detector data therefore comprises only the time-stamped energy data of the detected photons.

In some example embodiments, the arrangement 14(c) may have another optional detector arrangement 14°(c) to collect the other coincidence photons as it has lower noise as one rejects single events which includes many non-PET events.

By measuring over a time interval, in time differential mode, one can form additional bins in time (time slices) and extract the isotopic composition from the life-times as will be described below.

The system 10 may comprise a memory storage device 16 and a processor 20 configured to perform various data processing and control operations at least to analyse the material M based on the 511 keV photons detected by the detector arrangement 14, particularly to determine a composition thereof.

Though certain processing steps are attributable to the processor 20 as described herein, it will be appreciated by those skilled in the art that where applicable, certain steps may be achieved by the detector arrangement 14 and/or other components of the system 10. Moreover, the processing steps referred to herein with specific reference to the processor 20 will be understood by those skilled in the art to refer to method steps which need not necessarily be tied to the processor 20 as the case may be.

The processor 20 may be communicatively and/or electrically coupled to the memory device 16 and/or the detector arrangement 14 and/or the irradiator 12 in a hardwired fashion, or in a wireless fashion.

In one example embodiment, the processor 20 is communicatively coupled to the arrangement 14 via a communications network which may comprise one or more different types of communication networks.

The system 10 may thus comprise suitable communications modules to communicate over the communication network.

The communication network may be one or more of the Internet, a local area network (LAN), a wide area network (WAN), a metropolitan area network (MAN), various types of telephone networks (e.g., Public Switch Telephone Networks (PSTN) with Digital Subscriber Line (DSL) technology) or mobile networks (e.g., Global System Mobile (GSM) communication, General Packet Radio Service (GPRS), Code Division Multiple Access (CDMA), and other suitable mobile telecommunication network technologies), or any combination thereof.

It therefore follows that though it may not necessarily be practical, it is envisaged that in some example embodiments, the components of the system 10, particularly, the processor 20 need not be at the site of the detector arrangement but may be remote therefrom.

For example, nothing in the present application precludes a cloud- based analysis of detector data captured by the detector arrangement 14. The processor 20 may be one or more processors in the form of programmable processors executing one or more computer programs to perform actions by operating on input data and generating outputs.

The processor 20 as well as any computing device referred to herein, may be any kind of electronic device with data processing capabilities including, by way of non-limiting example, a general processor, a graphics processing unit (GPU), a digital signal processor (DSP), a microcontroller, a field programmable gate array (FPGA), an application specific integrated circuit (ASIC), or any other electronic computing device comprising one or more processors of any kind, or any combination thereof.

In one example embodiment, the processor 20 may be embodied in a computing device such as a computer 18 and thus these may be interchangeably referred to herein. Though not illustrated, it will be appreciated that the system 10, for example, the computer 20 may comprise one or more user input devices (e.g., a keyboard, a mouse, imaging device, scanner, microphone) and one or more output devices (e.g., a Liquid Crystal Display (LCD) panel, an Augmented Reality display, a sound playback device (speaker), switches, valve, etc.).

In one example embodiment, not illustrated, the processor 20 is communicatively coupled to the detector arrangement 14, for example, via one or more data acquisition {(DAQ) computers or modules configured to acquire and process raw signals from the detector arrangement 14 in a conventional fashion.

The memory storage device 16 may be in the form of computer-readable medium including system memory and including random access memory (RAM) devices, cache memories, non-volatile or back-up memories such as programmable or flash memories, read-only memories (ROM), etc., for example, on the computer 18. In addition, the device 16 may be considered to include memory storage physically located elsewhere in the system 10, e.g. any cache memory in the processor 30 as well as any storage capacity used as a virtual memory, e.g., as stored on a mass storage device.

The computer programs executable by the processor 20 may be written in any form of programming language, including compiled or interpreted languages, declarative or procedural languages, and can be deployed in any form, including as a stand-alone program or as a module, component, subroutine, object, or other unit suitable for use in a computing environment. The computer program may, but need not, correspond to a file in a file system. The program can be stored in a portion of a file that holds other programs or data {e.g., one or more scripts stored in a mark-up language document), in a single file dedicated to the program in question, or in multiple coordinated files (e.g., files that store one or more modules, sub-programs, or portions of code). The computer program can be deployed to be executed by one processor 20 or by multiple processors 20, even those distributed across multiple locations.

The multiple locations may be located in one geographical area or multiple geographical locations.

The computer programs may be stored in the memory store 16 or in memory provided in the processor 20 and/or the computer 18 as the case may be.

Though not illustrated or discussed herein, it will be appreciated by those skilled in the field of invention that the system 10 may comprise a plurality of logic components, electronics, driver circuits, peripheral devices, etc. not described or illustrated herein for brevity.

In particular, the processor 20 is configured to receive detector data comprising at least time-stamped energy data or raw data indicative of and/or associated with 511 keV photons emitted from the activated or transmuted material M and detected in a temporal fashion over the detection time interval by the detector arrangement 14. The detector data may be one or more time differential signal/s or may contain information pertaining to one or more time differential signal/s acquired over the time detection time interval.

The term “temporal fashion” may be understood to be in a sequential fashion and/or a time-based fashion and/or iterative fashion and/or time differential fashion within the detection time interval.

The detection time interval may be a predetermined time interval of a fixed duration after irradiation of the target material M.

In some example embodiments, the detection time interval is ideally selected to be between one third (of the shortest) and three times (the longest) of the decay constants of the positron emitting isotopes in the activated or transmuted material M.

If one is sure of the major PET isotope composition, and merely wants to measure their relative concentrations, then one can depart from this ideal case, as detection time interval may be highly optimizes to be shorter and still be able segment the composition of the material into its known constituents.

From a low level, it will be understood by those skilled in the art that the processor 20 may be configured to implement the detection time interval by controlling the detector arrangement 14 to only detect annihilation photons in the detection time interval after irradiation.

However, nothing precludes the detector 14 from continuously detecting annihilation photons emitted from the activated or transmuted material M and the processor

20 being configured to process only the detector data received from the detector arrangement 14 within the detection time interval. In any event, with PET data acquisition over a detection time interval which is long compared to the life-times of interest, the decay of the intensity of detected photons may be observed, and the life-time components in it may be extracted and thereby identify the elemental composition. It will be noted that the 511 keV photons may be emitted by various positron emitting isotopes at different times depending on the temporal decay profile of each positron emitting isotope. The temporal decay profile may be understood to mean a beta plus decay profile as mentioned herein. The processor 20 may be configured to temporally resolve the detector data acquired over the detection time interval to determine which positron emitting isotope/s are present in the activated or transmuted material M. In one example embodiment, the processor 20 may be configured to bin the detector data, particularly the time-stamped energy data, and generate a histogram thereof. It will be noted that by determining the concentrations, is meant “approximate concentrations”, as the case may be. In this way, the processor 20 may be configured to determine which positron emitting isotopes are present in the activated or transmuted material M by resolving the 511 keV photons detected by the detection arrangement 14 temporally by determining or identifying which positron emitting isotopes are dominant at different times during the detection time interval. The positron emitting isotopes identified may be a proxy for their corresponding “parent” elements which they were transmitted from thereby facilitating identification of the elements in the material M. For example, "carbon may be a proxy for carbon, or the like.

Moreover, the processor 20 may be configured to process the detector data received from the detector arrangement 14 to determine relative and/or absolute concentrations of positron emitting isotopes with the so called 511 keV peak. This of course leads on to the determination of the composition of the material M. In particular, the elemental composition of the material M. More particularly, a molecular composition of the material M which may be useful to identify certain types of material. Referring to Figure 6 which shows a time differential signal acquisition 22 of PET isotope emissions over a detection time interval by way of the detector arrangement 14 which leads to a PET gamma ray spectroscopic line at 511 keV 23 as a time sequence of signals, getting weaker in time, wherein the X-axis shows the energy of the photons detected by the arrangement 14 in keV and the Y-axis shows the detector hit counts per second on the arrangement 14. In one example embodiment, the processor 20 may be configured to receive detector data from the detector arrangement 14 with similar information contained in the plot in Figure 6. The information may be in a high level as in the form illustrated in the plot in Figure 8, low level in the form of raw signal data from the detector arrangement 14, or somewhere in between.

Notwithstanding, in one example embodiment, the processor 20 may be configured to decompose the 511 keV peak into several exponential components to determine relative concentrations of PET isotopes within the 511 keV peak. In this regard, the processor 20 may be configured to process the detector data to effectively split the events (photon hit event) detected by the detector arrangement 14 over the detection time interval into variable size time slices, ensuring that there are enough events in each slice to enable accurate fitting the evolving peak parameters. It will be understood that the time slices may be time points or segments within the detection time interval. The size of the peak for each time slice divided by the time interval gives the counts per second at that point in time. This is then graphed against time to show the change in activity. When fitted as a sum of exponential decays, this gives activity and life-time for each constituent As mentioned, the processor 20 may be configured to analyse the time spectrum of the PET isotope signal strength so as to determine and/or identify various PET isotopes present in the material M.

Figure 7 shows a total number of detector events in the 511 keV peak observed within a time slice. In particular, it shows an extraction of data pertaining to isotopes of oxygen 24 (*Oxygen), carbon 26 ("'Carbon), and then Potassium 28 (*® Potassium), as well as a combined fit 29 of all components together versus time. This is an example of the analysis of the oxygen and carbon content of Kimberlite and represents a temporal decay curve or profile for the time slice. As mentioned above, the total positron emission activity may, in one example embodiment, be determined in a series of successive time slices by the processor 20. When the changing activity of photons detected over the detection time interval is graphed as function of time after irradiation, it represents the sum of the exponential decays of the positron emitting isotopes that are present in the activated or transmuted material M, each of which has a different half-life, In this regard, in one example embodiment, the processor 20 is configured to resolve the graphed signal into its exponential contributions by performing a Laplace transform on the graphed signal. This is similar to a Fourier transform, but with real instead of complex exponentials, defined as: CLA) = | Frye ta (1)

SH , wherein f represents the signal being analysed, and s represents a decay constant of a particular value, so that L{(s) becomes the entire spectrum over all s values of decay constants present in the entire time spectrum.

A Laplace transform will resolve the signal into exponential contributions where there is no prior knowledge of which contributions are present. In most reakworld situations however, there is a strong chance that prior data of the elements present in the target material may be known. In this case, the processor 20 is configured to rather resolve the detector data, particularly the time-stamped energy data in the form of one or more signal/s by fitting the same as a sum of exponentials of known life-times. In one example embodiment wherein the detector data comprises 3D tomographic images or tomograms, referred to as “PET 3D images”, each voxel in the PET 3D image may have its own time dependent exponential decay curve or profile, for example, as illustrated in Figure 7 for kimberlite, being the sum of several contributions of various PET isotopes. The processor 20 is configured to analyse each voxel for its own composition in terms of the constituent PET isotopes. Following this, the processor 20 may be configured to generate or create images for the various PET isotopes separately, leading to several images. When a structure is formed by connected voxels, then this is known as segmentation, and in this case, it is segmentation into given forms with an elemental composition. If there is a correlation between the elements in the voxel, indicative of a given molecular compound, then the activated or transmuted material can be segmented into separate shapes of molecular or material composition.

The material segmentation then occurs on a voxel-by-voxel complete analysis of each time-differential decay curve, and then connecting voxels into a form, in order to render 3D shapes of given known compositions.

The aforementioned may be performed by the processor 20.

Moreover, it will be noted that the processor 20 is configured to convert from the PET intensity to absolute PET isotopic concentrations, visualised and segmented in 3D, wherein PET intensity is the concentration of PET events, i.e. number of PET events per unit volume.

Up to this point, only relative concentrations of isotopes are known. Thus, in order to determine absolute concentrations, the processor 20 is configured to determine the foregoing by implementing two methods, internal and external calibration. For the internal calibration method, a physics model for the measurement is used. This is based on knowing several parameters. Firstly, there are the cross sections (probabilities) for the activation of specific PET isotopes, including all pathways to their formation in the activation stage, and also in the decay stage. This is constructed by a computer-implemented simulation, for example, Monte Carlo simulation. Then one has the acceptance and efficiency of the detection system. One has the flux of the incident beam of electrons from the irradiator 12 as described above, the time of acquisition and the number of events detected in a given time. One makes dynamical corrections for elapsed time since irradiation and the time of acquisition. Finally one has a relationship between observed initial activity and the density of the parent nuclei in the sample.

Ay =ApoDtkye 2) 1 — eA ky = —— (3) At ‚ wherein p is the atomic concentration of the parent nuclei © is the Monte Carlo calculated effective cross section p is the electron flux t is the irradiation time ka is the decay multiplier € is the detector efficiency A is the decay constant of the isotope The process of quantitative extraction of the elemental concentration rho from the observed initial activity Ax therefore involves modelling the real evolving energy distribution of the mixed radiation field with the energy dependent cross section to get an effective cross section, as indicated above.

One then applies the formulas (2) and (3) using the measured initial activity Ax, and calculate the elemental concentration rho.

This may comprise using computer implemented models or simulations.

Ultimately, the observed time dependent signal decomposition is related to an elemental concentration.

In the case of PET and SPECT, then this concentration will be on a per voxel (as in the detector arrangement 14(a)) or pixel (as in the detector arrangement 14(a)) case, in terms of the 3D or 2D nature of the image formation process.

In the case of the 1D system, one has a homogenised result for the whole target material M observed.

It is also possible to benchmark continuously or replace the calculational approach with an approach based on phantom standards.

The phantom material must conform as closely as possible to the actual material and the concentrations must be measured as standard concentrations by other means. Then, the real application may be cross calibrated against the phantom standards.

The system 10 may be used to detect materials of known elemental composition by identifying one or more elements therein in the manner described herein. The system 10 may be used to determine the composition of an unknown material also by identifying one or more elements therein in the manner described.

Referring to Figures 3 to 5 of the drawings where other example embodiments of material analysis system in accordance with an example embodiment of the invention are generally indicated by reference numerals 30, and 40.

As mentioned above, the system 10 may be a general or generic analysis system 10 which is configured to determine the composition of a target material M, wherein the composition of the target material M may be important for certain applications. In this regard, the system 10 may be adapted to, and/or form part of, a wider system or installation.

For example, in Figures 3 and 4, the system 10 as described herein is embadied as a coal analysis system 30 provided in a coal handling environment C which may be a coal mine, a coal fired power plant, or the like configured to analyse target material M in the form of coal C in an online fashion to determine a composition thereof.

In Figure 5, the system 10 as described herein is embodied as a mine detection system 40 which may be provided in a moveable carrier 42 to detect explosives E contained in landmines buried beneath a surface in a minefield. The material M may thus be the ground G which is irradiated or it could be the explosives E, as the case may be.

It follows that the comments made above with respect to the system 10 also apply to the system 30 and 40 thus similar parts will be referred to by the same reference numerals.

In Figure 4, the coal analysis system 30 is provided in a flow path 32 of coal C in a coal fired power plant, particularly as a deviation of the main low path 32 in a sampling path

34. The sampling path 34 deviates from the main flow path 32 but re-joins the flow path 32 after interacting with the system 30. The flow paths 32, 34 may be defined by conveyor belts. These conveyor belts may form part of the system 30 thus the system 30 may be online. In general, low quality coal with a high moisture content and/or low calorific content is undesirable in a coal fired power plant and may cause damage, downtime and rolling blackouts if used for a prolonged period of time therein. Low quality coal is difficult to analyse in an online or substantially real-time fashion. Conventional methodologies to analyse coal to determine the moisture content and/or calorific content thereof involves laboratory testing simply which often includes destroying the sample and the results thereof require specialist analysis to decipher. In this regard, the coal analysis system 30 which uses the techniques described above with respect to system 10 may thus provide an advantageous way of analysing coal.

In this regard, the system 30 also comprises an irradiator 12 to irradiate coal C with photons of approximately 40 MeV, and a beam current of 55 pA thereby to activate the coal sample C by forming one or more positron emitting isotopes in the coal sample due to the interaction of photons from the irradiator 12 and one or more elements in the coal sample C, and a detector arrangement 14 which is communicatively coupled to a processor 20 which is configured to receive detector data from the detector arrangement 14 indicative of the detection of the back-to-back co-linear and co-incident 511 keV annihilation photons by the detector arrangement 14, for example, the detector arrangement 14(a) in a temporal fashion over the detection time interval.

As mentioned, the system 30 may comprise a suitable conveyor to transport the coal from the irradiator 12 to the detector arrangement 14. The conveyor may be configured to receive, for example, in an iterative fashion at predetermined or random times spread out during a period of time, a sample of coal from hold a coal sample M relative to the irradiator 12 to irradiate the coal sample C..

It will be noted that the processor 20 may be configured to process the detector data to identify individual elements present in the coal sample C based on their corresponding positron emitting isotopes, wherein the coal sample C is representative of the volume of coal C in the main flow path 32.

In the example embodiment illustrated, the system 30 is configured to determining the composition of coal C insofar as predetermined elements are concerned. In particular, the system 30, particularly the processor 20, is configured to determine an oxygen and carbon composition of the coal sample C based on the photons emitted therefrom by the positron emitting isotopes of Oxygen and Carbon, viz. *Oxygen and "Carbon, respectively. The positron emitting isotopes of oxygen representative of the oxygen present in the coal sample C may be used as a proxy for, or a marker indicative of, a moisture content of the coal sample C. This may be extended to the wider stream of coal from which the coal sample C was taken. Similarly, the positron emitting isotopes of carbon representative of carbon present in the coal sample C may be used as a proxy for, or a marker indicative of, a calorific value of the coal.

The processor 20 may be configured to generate 3D tomographic images of the elemental compositions. Moreover, the processor 20 may be configured to include a correction for real-world scenarios.

The positron emitting isotope of oxygen has a half-life of 2 min, while the positron emitting isotope of carbon has a half-life of 20 min. In this regard, the processor 20 may be configured to conceptually perform a two component fit over 5 min of data, with the strong assumption that carbon and oxygen dominate the signal composition in this time interval, which must begin within 10 seconds of the activation or transmutation by the irradiator 12 terminating. In one example embodiment, the detection time interval is selected to be 5 minutes. It follows that the coal C may be sampled every 5 minutes. The sample size need not be too small or too large and may be approximately 3 kg.

The processor 20 may be configured to extract and image separately carbon and oxygen, and segment quantitatively to moisture content and calorific value of coal, imaged in 3D substantially in a manner described above. The processor 20 is further configured to use the determined composition of the coal sample C, insofar as the oxygen and carbon composition is concerned, to determine a moisture value or measure associated with the coal based on the determined oxygen in the coal sample C, and to determine a calorific value or measure associated with the coal sample C based on the determined carbon in the coal sample C.

It will be understood to those skilled in the art that the actual mapping of oxygen and carbon 3D concentrations to moisture and calorific value may be determined through test work and quantifiable assumptions based on chemical knowledge or data. Some supplementary information based on other simultaneous information (such as an optical spectroscopy) could be collected in real time as well.

Moreover, it will be noted that in some coal analysis example embodiments only oxygen or carbon is of interest for analysis to determine either the moisture content of the coal sample C or the calorific content of the coal sample C, and not both.

If the sample C has a moisture content and/or calorific content outside of a predetermined tolerance range/s, the system 30 may be configured to generate a suitable alarm signal. The suitable alarm signal may be suitable to operate the suitable conveyor to stop the main supply of coal, or the like, for example, to prevent a coal fired power plant from burning coal, a sample of which is determined to be too moist or has an unacceptable calorific content. Instead, the alarm signal may be an audible, visual, or tactile signal operable to control a suitable audible signal means such as a suitable electrically actuated siren, visual signal means such as a light, or a suitable vibrating means. When operated on by a suitable processor, the alarm signal may be configured to generate a suitable warning message that the characteristics of the coal sample C is outside of predetermined range/s.

In this way, determining the composition of the material M also comprises determining characteristics of the material M.

In Figure 5, the system 10 is embodied in a land mine detecting system 40 configured to detect landmines underground by detecting explosive material E beneath a surface G on which the system 40 travels. The system 40 may be incorporated into a suitable armoured vehicle such as a tank, or the like.

In this regard, the system 40 also comprises an irradiator 12 mounted to a boom off the ground G to irradiate the ground over which the system 40 travels with photons of approximately 40 MeV, and a beam current of 55 uA thereby to activate positron emitting isotopes corresponding to certain elements present in explosive materials E which are contained in a landmine which may or may not be present beneath the ground being activated or transmuted. In particular, the irradiator is configured to activate positron emitting isotopes of carbon, nitrogen, oxygen, and Fluorine which are usually present in explosive materials E present in landmines.

The system 40 comprises a detector arrangement 14 which is communicatively coupled to a processor 20. Since it is not possible for the detector arrangement 14 to detect both back-to-back co-linear and co-incident 511 keV annihilation photons as the target material in the form of explosive material E is under the ground G, the detector arrangement 14 may comprise the arrangement 14(b) or 14(c) and may therefore have similar detection capabilities as described above to detect “singles” of the pairs of 511 keV annihilation photons over a detection time period.

It will be noted that the processor 20 may be configured to process the detector data received from the detector arrangement 14 to identify individual elements present in the ground being analysed based on their corresponding positron emitting isotopes. If, within the detection time period, single photon hits at different time points in the time interval indicate the presence of positron emitting isotopes of carbon, nitrogen, oxygen, and Fluorine, the processor 20 may use these isotope indications as presence of the corresponding elements in the ground which would be indicative of an undetonated landmine which must be safely removed from the ground.

To this end ‚the system 40 may be configured to generate a suitable landmine detection signal which is indicative of a landmine being detected in the area being investigated with the system 40.

The applications of the system 10 and the disclosure herein may be varied as the disclosure herein permits the detection of low Z number light elements are primarily elemental components of many organics, narcotics, plastics, and explosives. The correlation between these elements is in fact a fingerprint for these materials. Table 1 below details the light element composition of these materials in C, N and O and F.

Table 1: Carbon, Nitrogen and Oxygen concentrations of various compounds Explosives / narcotics scanning C N © ¢ N O Ammonium nitrate 0 2 3 Nitrocellulose 6 3 10 C-4 8 1 11 Nitroglycerine 3 3 9 RDX/HMX i 2 2 ENT 7 3 6 EGDN 2 2 ö Tetryl 7 5 8 PETN 5 4 12 Picric acid 6 3 7 Heroin 17 1 1 Morphine 17 1 3 LSD 20 3 1 Mandrax 16 2 1 Cocaine 17 1 4 is OAC, COMPOURAS ee Paraffin wax 18 ¢ © Sugar 13 0 12 Polyethylene 1 û 0 Fea{S043z — 15H0 0 0 27 Ethanol 2 0 1 Wood 22 4 12 Methanol i û i Paper 6 0 5 Water 0 0 1 Cotton 18 0 13 Ammonium acetate 2 1 2 Silk 8 5 4 Nylon 6 1 1 Orlon 6 2 ¢ Lucite 2 0 1 Wool 6 3 3 Polyurethane 5 2 1 Melamine 1 2 0 Acetamide 2 1 1 Polyester 3 0 1 Benzene 6 0 0 Aluminium oxide 0 0 3 ‘Table 9.1: Carbon, nitrogen and oxygen concentrations of various compounds.

In Figure 8, a triad of these, just C, N and O are plotted in three dimensions to illustrate the aforementioned point.

This means that any technique that could perform elemental analysis and find these correlations, would succeed in identifying one of these materials.

Adding the imaging capacity is a big improvement, as it can happen that a smuggler or similar agent could spike a sample so as to change the average composition correlations.

Imaging would then enable the elemental composition to be determined on a voxel by voxel or pixel by pixel basis, to frustrate such attempts at concealment.

Imaging endows an additional sensitivity and also a capacity to thwart attempts at concealment.

Imaging also gives a capacity to do composition identifications atthe object level.

As can be seen from the foregoing example embodiments, the applications of the technology disclosed herein to determine the composition of material may be varied and may have application far and wide, wherein the basis remains that the material being analysed is irradiated with photons at an energy level at which GDR occurs thereby to activate or transmute the material by forming positron emitting isotopes therein, wherein photons emitted as a result of positron emission are detected in a sequential fashion in the detection time interval, wherein the elemental composition and ratios thereof in the material are determined or calculated in manner described herein based on the annihilation photons detected sequentially in the detection time interval.

Though not illustrated and described in detail, the disclosure herein may be used to measure carbon agglomeration as a function of dose (neutron ageing) in reactor pressure vessel steel. In particular, it will be noted that as reactor steel ages during operation in a nuclear power reactor, it is subjected to very high neutron doses, of the order of GGrays per year. Itis of interest to study the structure of the steel to determine when it needs to be replaced. The action of neutron irradiation leads to (amongst other things) the agglomeration of the carbon in the steel. There is currently no non-destructive method to image the early formation of these carbon nodules. The determination of the composition of the steel in a manner as described herein may be used to determine agglomeration of carbon inthe steel if the positron emitting isotope of carbon is formed and 511 keV photon/s are detected and processed in a manner described herein. The disclosure as described herein may be used for the measurement of oil in drill cores for oil prospecting. Oil is carbon rich and thus the disclosure herein may be extended to provide a rapid method for on-site imaging of the 3D distribution of carbonaceous deposits in rock revealed in drill cores. Moreover, the disclosure herein may be used for the measurement of fat content in food such as meat. The distribution of fat in meat, and its overall content is another example of a carbon rich material with a spatial distribution within another material. The disclosure herein may provide a rapid method for in situ imaging of the 3D distribution of the fat content and marbling within meat.

It will be understood by those skilled in the art that the methodology described herein that the foregoing example applications of the present invention is not a closed set and may be added to. Moreover, though no further information is provided with respect to some of the foregoing applications, it will be understood by those skilled in the art.

Referring now to Figures 9 to 11 of the drawings where flow diagrams of methods in accordance with example embodiments of the invention is generally indicated by reference numerals 80, 70, and 90, respectively. The examples methods 60, 70, 90 may be described, in a non-limiting example, in use with systems of the type described in Figures 1, and 3 to 5 but nothing precludes the methods 60, 70, 90 from being used in other systems not illustrated. In Figure 9 of the drawings, a block diagram of a method for analysing a sample of a target material M in accordance with an example embodiment of the invention is generally indicated by reference numeral 80, which reference numeral may hereinafter be used to refer to the method. The method 60 may be a method associated with the operation of the systems 10, 30, 40 as described herein thus it follows that the method 60 comprises the step of irradiating, at block 62, a target material sample M with bremsstrahlung photons having an energy in a range of between 20 - 30 MeV by way of the irradiator 12 in a manner described herein. Also, as mentioned, at this energy, a giant dipole resonance (GDR) occurs due to photonuclear reactions between the photons and one or more elements present in the target material M. In this way, the irradiation step 62 may thus be an activation or transmutation step which creates positron emitting isotopes out of nearby naturally occurring isotopes in the sample material M in the manner described above. The result of activation or transmutation is that the activated or transmuted material M comprises one or more positron emitting isotopes corresponding to one or more respective parent elements in the material M.

The method 60 then comprises detecting, at block 64, one or both of the pairs of back-to-back co-linear and co-incident gamma ray photons of 511 keV by way of the detector arrangement 14. This step at block 64 may be immediately after the irradiation step

62. An important feature of the method 60 is that the photons are detected in a temporal fashion over a detection time period without holding the activated or transmuted material for a predetermined period of time to allow for dominant beta decay to occur. In this way, all relevant types of beta decay in the activated or transmuted material M is detected during the detection time interval in a temporal fashion.

The detection step may comprise time stamping the detected annihilation photons with a time within the detection time interval that the annihilation photons are detected. The time-stamped energy data as described herein may be generated in this way for the detection time interval. The time stamping of the detected annihilation photons may be done automatically by the detector arrangement 14 and/or the processor 20.

The method 60 then comprises determining, at block 68, all or part of a composition of the material M based at least on the photons detected temporally in the detection time interval, wherein the photons detected at certain times in the interval are indicative of their corresponding positron emitting isotope which in turn is indicative of the so-called parent element.

In one example embodiment, the method 60 may comprise generating a histogram of the arrival time of the photons of the appropriate energy over the detection time interval.

In other words, a histogram of the time-stamped energy data. In this way, when the arrival time of the annihilation photons are histogrammed in time bins, for example, via the processor 20, the decay pattern or profile of the activated or transmuted material M is revealed.

The time evolution of this decay or decay pattern/profile/signature is determined by the sum of all exponentially decaying components within it. These individual exponential decay components have a characteristic life-time or exponent factor, which fingerprints back to a specific isotope. The isotopes within the set are extracted by a mathematical process as previously explained. For example, if there are two components with life-time Ay and Az then the extraction process will reveal the relative amounts of each, which can be quantitatively related to their atomic concentrations.

The step 66 may include identifying one or more elements present in the material M based on the detected photons. In this regard, determining the composition of the material M may be understood to also include identifying one or more elements in the same.

The level of abstraction in determining the composition of the material M in step 66 may be varied in that it may entail determining the elemental composition of the material M as well as a molecular composition. Moreover, using the correlations mentioned previously with reference to Figure 8 the method 80 may comprise using the determined composition insofar as two or more elements are concerned to identify an unknown material. The method step 66 may also include determining the relative and/or absolute concentrations of elements in the material M as described herein based on the detected photons.

In any event, it will be appreciated that the determination step at block 66 may be proceeded by further steps of characterising the material as well as making certain decisions. For example, in the case of the system 30 and 40 described herein, the determination of the composition enables the moisture content and/or calorific content of the coal sample C to be determined or a landmine underground to be determined. This determination may be used to operate suitable equipment to extract the detected landmine or stop the processing of coal with poor characteristics as will be understood by those skilled inthe art.

Referring now to Figure 10 of the drawings where another example embodiment of the method in accordance with an example embodiment of the invention is generally indicated by reference numeral 70.

The method 70 may be an expansion or a more lower level processing of the processor 20 in determining the composition of the material M in step 66 of the method described in Figure 9. The method 70 may have intervening steps which are not mentioned herein, moreover, it will be understood by those skilled in the art that the description of one means of performing the method 70 need not limit the scope of the disclosure herein.

In particular, the method 70 comprises receiving or acquiring detector data temporally over a time interval, wherein the detector data is associated with detections of photons having an energy at or around a predetermined energy level associated with annihilation photons emitted from the activated or transmuted material due to positron emissions within the activated or transmuted material. In this regard, the method 70 comprises receiving detector data in a time differential mode or time differential manner at block 72. As alluded to herein, this may be a feature of the detector arrangement 14 and/or the processor 20 as the case may be.

In one particular example embodiment, the method 70 may comprise storing or binning the received detector data associated with detections of annihilation photons from the detector arrangement 14 for the PET isotopes in time slices in the memory device. In this way, the method 70 is able to perform 511 keV counting over a time interval at block

74. The detector data binned may be the time-stamped energy data of the photons detected by the arrangement 14. It will be noted that when received from the arrangement 14, the detector data may be raw in a sense that it comprises information indicative of at least the energy of the detected photons and the number detector hits for a particular time slice. As mentioned above, spatial data may be an optional component of the detector data. Thus in its basic embodiment, for example, for a 10 second time slice, the detector data received may comprise data indicative of at least the number of photons detected in the 10 second time slice and the energy of the detected photons.

In one example embodiment, the method 70 may comprise reconstructing, at block 76, the detector data comprising the time-stamped energy detector data or time differential PET signal strength as well as the spatial data associated with the detection by the arrangement 14 as 2D or 3D position dependent image, over the detection time period P.

In the case of PET, there is a time spectrum of PET intensity for each voxel. In the case of SPECT, this is a 2D image, with a time spectrum of SPECT intensity for each pixel. In the case of no spatial resolution or no spatial data available, the time differential spectrum is a single value that applies to the entire material region being interrogated.

In this way one therefore has a richer data set than a normal PET or SPECT 3D or 2D image, as one has in addition, within the 3D voxelised or pixelated map, an entire time spectrum, now available for segmentation into elemental / molecular composition. Not that there are realisations of SPECT which are also capable of a degree of 3D rendering.

The method 70 may comprise decomposing the reconstructed time differential signal strength into several exponentials or exponential components, at block 78, wherein the elemental composition is extracted based on the exponentials or exponential components. This is done on a per voxel or per pixel basis.

As mentioned above, the general approach with unknown constituents is LaPlace transforms, given in equation (1). When there is a good appreciation of possible isotopic constituents, a suitable fitting algorithm such as a least squares algorithm is applied by the processor 20 to perform a fit, where the fit function is defined as the sum of the exponential decays for each of the possible constituents. This fit is very constrained, and it performs the job in a robust way.

In this way, the elemental composition of the material is determined in block 80 on a per voxel or per pixel basis. It will be noted that the term “composition” as described herein need not refer to an exhaustive and/or all-inclusive composition and thus may be understood to mean all or part of the composition. In particular, the term composition may be interpreted as being a partial composition of a handful of elements, typically those having positron emitting isotopes. Thus a multi-element material may only be determined to have an elemental composition, insofar as the system 10 as described herein is concerned, comprising of C, N, and O despite having other elements. However, in many cases just the presence of a handful of identified elements in specific combinations and/or concentrations may be enough to identify the material and thus additional elements therein.

Based on the elemental composition, the method 70 may comprise determining, at block 82, a molecular composition of the material M.

Once the tomographic (3D) or radiographic (2D) shape is know from step 76 on a 3D voxel or 2D pixel basis, and the elemental or molecular composition is known from the action of steps 78 - 82, then there can be a segmentation into shapes of commonality, by observing the same correlations in neighbouring voxels / pixels, and collecting such voxels / pixels into the segmented shapes. This is step 84 also carried out by the processor 20 and brings a vast increase in information, as we then have quantitative 3D visualization of composition with segmentation into shapes.

Though not illustrated, following on from block 72, it will be appreciated that in some example embodiments, for each time slice of detector data binned in a temporal fashion in the detection time interval, the method 70 may comprise generating a plurality of histograms according to energy of the photons detected. In other words, the method 70 may comprise histogramming each time slice of detector data received (and stored or binned) in the detector time interval according to energy. This may be an average energy of the detected photons over the time slice, as well as an average photon count over the time slice, as the case may be.

As mentioned herein, the energy or energy range of interest for the detected annihilation photons is around 511 keV. It follows that for each histogram, the method 70 may comprise implementing an annihilation energy range or window around 511 keV that covers a 511 keV peak, being the energy peak associated with the annihilation photons of interest. It follows that in one example embodiment, the method 70 comprises fitting the shape of the histogram within this window by a function with two components, the first of which captures the background photon hit count, and the second of which captures the size of the 511 keV peak abave the background photon hit count. The 511 keV peak size from each of these fits gives one data point.

All of the data points from all of the time slices are then plotted against their weighted average time; this graph then shows the decay profile, and can be fitted as the sum of exponential decays to extract the relative concentrations of isotopes that are present the material M as described herein.

Referring now to Figure 11 of the drawings where another example embodiment of the method in accordance with an example embodiment of the invention is generally indicated by reference numeral 90.

The method 90 is typically also associated with the processing taking place by the processor 20 in determining the composition of the activated or transmuted target material M. In particular, the method 90 illustrated is a methodology of imaging the received detector data from the detector arrangement 14, typically by way of the processor 20. Moreover, the method 90 may be a method of imaging a target material, wherein the method comprises the irradiating and detecting steps as described above with reference to the previous Figures, for example, Figure 6. The method 90 comprises determining at block 91, whether or not spatial differentiation is required at block 91.

If spatial differentiation is required, then the method 90 comprises determining, at block 92, whether or not the system 10 is able to detect the annihilation photons emitted from opposite sided of the activated or transmuted target material or object M. The term “object” may be understood as “material” herein. “Opposite sides” may be understood to mean on a top and bottom, or laterally flanking sides.

If it is possible to detect annihilation photons emitted from opposite sides of the activated or transmuted material M, then one has full spatial data associated with the LoR though detector hit locations as well as the time of the detector hits and energy level (which should be 511 keV), the method 90 comprises generating a 3D tomography or 3D PET image of the detection of the photons, at block 93.

On the other hand, if the system 10 is not able to detect photons emitted on opposite sides of the activated or transmuted material M in step 92, but is only able to detect photons emitted from the activated or transmuted material M on one side thereof, the method 90 comprises generating, at block 95, a 2D or 3D SPECT (Single Positron Emission Computed Tomography) image of the activated or transmuted material M. This may be the case where the detector arrangement 14(b) is used as a gamma camera.

It will be noted that if no spatial differentiation is required in block 91, the method 90 still comprises determining, at block 94 like block 92, whether or not the system 10 is able to detect the annihilation photons emitted from opposite sided of the activated or transmuted target material or object M.

If the system 10 is not capable of detecting annihilation photons emitted from opposite sides of the activated or transmuted material M, at block 94, the method 90 comprises counting the 511 keV photons with no imaging, at block 96, in a so-called “singles mode”, wherein the arrangement 14(c) may only detect a single photons and with energy discrimination at the 511 keV energy window only. This arrangement as described above may be the most cost-effective implementation possible if competition from sources of noise is minimal.

On the other hand, if the system 10 is indeed capable of detecting annihilation photons emitted from opposite sides of the activated or transmuted material M, at block 94, the method 90 comprises counting the 511 keV photons with no imaging, at block 98, in so called “coincidence mode”, wherein the partner photon is detected, for example, by the detector arrangement 14°(c) in coincidence condition, for noise reduction (a benefit of PET).

It turns out the coincidence condition on the 511 keV gamma ray is good at reducing background radiation from any non-PET radiation, as it is dominantly the PET radiation that will have a pair of co-incident photons.

In this way, various imaging schemes may be used to image the positron emitting isotopes in the material M.

Referring now to Figure 12 of the drawings which shows a diagrammatic representation of the machine in the example of a computer system 100 within which a set of instructions, for causing the machine to perform any one or more of the methodologies discussed herein, may be executed. In other example embodiments, the machine operates as a standalone device or may be connected (e.g., networked) to other machines. In a networked example embodiment, the machine may operate in the capacity of a server or a client machine in server-client network environment, or as a peer machine in a peer-to-peer (or distributed) network environment. The machine may be a personal computer (PC), a tablet PC, a set-top box (STB), a Personal Digital Assistant (PDA), a cellular telephone, a web appliance, a network router, switch or bridge, or any machine capable of executing a set of instructions (sequential or otherwise) that specify actions to be taken by that machine. Further, while only a single machine is illustrated for convenience, the term “machine” shall also be taken to include any collection of machines, including virtual machines, that individually or jointly execute a set (or multiple sets) of instructions to perform any one or more of the methodologies discussed herein.

In any event, the example computer system 100 includes a processor 102 (e.g., a central processing unit (CPU), a graphics processing unit (GPU) or both), a main memory

104 and a static memory 106, which communicate with each other via a bus 108. The computer system 100 may further include a video display unit 110 (e.g., a liquid crystal display (LCD) or a cathode ray tube (CRT)). The computer system 100 also includes an alphanumeric input device 112 (e.g., a keyboard), a user interface (Ul) navigation device 114 {e.g., a mouse, or touchpad), a disk drive unit 116, a signal generation device 118 (e.g., a speaker) and a network interface device 120. The disk drive unit 16 includes a non-transitory machine-readable medium 122 storing one or more sets of instructions and data structures (e.g., software 124) embodying or utilised by any one or more of the methodologies or functions described herein. The software 124 may also reside, completely or at least partially, within the main memory 104 and/or within the processor 102 during execution thereof by the computer system 100, the main memory 104 and the processor 102 also constituting machine-readable media. The software 124 may further be transmitted or received over a network 126 via the network interface device 120 utilising any one of a number of well-known transfer protocols (e.g., HTTP). Although the machine-readable medium 122 is shown in an example embodiment to be a single medium, the term "machine-readable medium" may refer to a single medium or multiple medium (e.g., a centralized or distributed memory store, and/or associated caches and servers) that store the one or more sets of instructions. The term "machine- readable medium" may also be taken to include any medium that is capable of storing, encoding or carrying a set of instructions for execution by the machine and that cause the machine to perform any one or more of the methodologies of the present invention, or that is capable of storing, encoding or carrying data structures utilised by or associated with such a set of instructions. The term "machine-readable medium" may accordingly be taken to include, but not be limited to, solid-state memories, optical and magnetic media, and carrier wave signals.

The invention as disclosed herein provides a novel elemental or molecular analytical technique, which can be used in a 3D or 2D or simple counting mode.

It will be understood by those skilled in the art that there may be many advantages to the methodology and system described herein, for example:

1. Bulk Analysis (Volume) - the activation step penetrates up to 160 mm sample thickness, and the 511 keV photon can escape from such a thickness, so the method is a bulk analysis method, not a surface analysis or a skin analysis method. Non-penetrating methods would have to grind or powder the sample in order to get the analysis result. Can be implemented in a quasi-online scenario, in that there is rapid (5 min) processing of batch extracted samples.

2. For higher Z elements, there is Instrumental Neutron Activation Analysis (INAA). This uses a 252-Cf source of neutrons, and the sample becomes activated and then banks of gamma ray detectors identify isotopes through their fingerprint gamma ray radiation. This can also do bulk samples (volume) but it cannot do carbon and oxygen. Moreover, as described herein, use of neutrons to activate material is undesirable, particularly when the present disclosure presents a “cleaner” alternative.

3. There are more complex nuclear activation methods, but these have not really left the laboratory whereas as mention the method and system disclosed herein can be implemented in an online scenario.

4. X ray fluorescence and X ray transmission (XRF and XRT) are prior art technologies used to analyse material. The former is a surface or at most a thin skin depth method which is not used for the lighter elements. The latter has poor resolution for elemental signatures even in multi-energy incarnations. It would not compete with a PET technique in many cases. These techniques can be evaluated on a case by case basis. Can be implemented in an online scenario.

5. Optical Reflection Spectrometry, Raman Spectrometry, Laser Fluorescence, other optical methods. These would also be surface methods or thin layer methods, and so would require sample processing for bulk samples. They would not be typically an online method as is the case in the method and system disclosed herein.

6. If imaging and non-destructive aspects are important for a bulk analysis, there is probably no competitor technique.

7. Unlike the MinPET application previously mentioned, the present disclosure does not seek to differentiate between different PET isotopes within a sample during detection based on differences in isotope life-times where different waiting times in a hold hopper or other hold system is employed before detection in a very short time window. Here we will have a specially tailored time window and then time differential or temporal data acquisition.

8. The determination of the composition of a target material as described herein may have widespread applications in a range of industries as an alternate, substantially online analysis tool, wherein the determination of the composition of the material may have further knock on processing, as the case may be.

Claims

CONCLUSIESCONCLUSIONS

1. Werkwijze voor het analyseren van materiaal, de werkwijze omvattende: het bestralen van een doelmateriaal met fotonen met een energie binnen een vooraf bepaald energiebereik waarbij een dipool reuzeresonantie (“giant dipole resonance”) (GDR) optreedt teneinde het doelmateriaal te activeren of te transmuteren als gevolg van fotonucleaire reacties tussen de fotonen en één of meer elementen die aanwezig zijn in het doelmateriaal; het detecteren van fotonen met een vooraf bepaald energieniveau dat wordt uitgestraald door het geactiveerde of getransmuteerde doelmateriaal als gevolg van positronannihilatie in het geactiveerde of getransmuteerde doelmateriaal, waarbij de fotonen worden gedetecteerd op een temporele wijze in een detectietijdinterval na bestraling; en het bepalen van een samenstelling van het doelmateriaal gebaseerd op ten minste de fotonen die temporeel in het detectietijdinterval worden gedetecteerd.A method of analyzing material, the method comprising: irradiating a target material with photons at an energy within a predetermined energy range wherein a giant dipole resonance (GDR) occurs to activate or activate the target material transmuting as a result of photonuclear reactions between the photons and one or more elements present in the target material; detecting photons of a predetermined energy level radiated from the activated or transmuted target material as a result of positron annihilation in the activated or transmuted target material, wherein the photons are detected in a temporal manner in a detection time interval after irradiation; and determining a composition of the target material based on at least the photons detected temporally in the detection time interval.

2. Werkwijze volgens conclusie 1, waarbij de werkwijze omvat het identificeren van het doelmateriaal gebaseerd op de bepaalde samenstelling ervan.The method of claim 1, wherein the method comprises identifying the target material based on its determined composition.

3. Werkwijze volgens conclusie 1 of conclusie 2, waarbij de werkwijze omvat het tijdmerken van fotonen die zijn gedetecteerd in het detectietijdinterval.The method of claim 1 or claim 2, wherein the method comprises time marking photons detected in the detection time interval.

4. Werkwijze volgens een van de voorgaande conclusies, waarbij de werkwijze omvat het continu detecteren van fotonen gedurende het detectietijdinterval, een vooraf bepaalde tijd na het bestralen van het doelmateriaal.A method according to any preceding claim, wherein the method comprises continuously detecting photons during the detection time interval, a predetermined time after irradiating the target material.

5. Werkwijze volgens een van de voorgaande conclusies, waarbij de stap van het bepalen van de samenstelling van het doelmateriaal omvat het bepalen van een samenstelling van elementen van het doelmateriaal.A method according to any preceding claim, wherein the step of determining the composition of the target material comprises determining a composition of elements of the target material.

6. Werkwijze volgens conclusie 5, waarbij de stap van het bepalen van de samenstelling van elementen van het doelmateriaal omvat het identificeren van één of meer elementen die in specifieke concentraties aanwezig zijn in het doelmateriaal gebaseerd op fotonen die worden geëmitteerd door één of meer daarbij behorende positron emitterende isotopen in het geactiveerde of getransmuteerde doelmateriaal gedurende het detectietijdinterval.The method of claim 5, wherein the step of determining the composition of elements of the target material comprises identifying one or more elements present in specific concentrations in the target material based on photons emitted by one or more associated therewith positron-emitting isotopes in the activated or transmuted target material during the detection time interval.

7. Werkwijze volgens conclusie 5 of 6, waarbij de stap van het bepalen van de samenstelling van het doelmateriaal omvat het identificeren van een type molecuul in het doelmateriaal door middel van het correleren van de bepaalde samenstelling van elementen teneinde samenstellingen van elementen van moleculen te kennen.The method of claim 5 or 6, wherein the step of determining the composition of the target material comprises identifying a type of molecule in the target material by correlating the determined composition of elements to know compositions of elements of molecules .

8. Werkwijze volgens conclusie 7, waarbij de stap van het identificeren van ten minste één type molecuul dat aanwezig is in het doelmateriaal wordt voorafgegaan door de stap van het bepalen van één of meer elementen die aanwezig zijn in het doelmateriaal, waarbij elke molecuul een onderscheidende samenstelling van elementen heeft.The method of claim 7, wherein the step of identifying at least one type of molecule present in the target material is preceded by the step of determining one or more elements present in the target material, each molecule having a distinctive composition of elements.

9. Werkwijze volgens een van de voorgaande conclusies, waarbij het geactiveerde of getransmuteerde doelmateriaal één of meer positron emitterende isotopen omvat die corresponderen met één of meer elementen die aanwezig zijn in het doelmateriaal.The method of any preceding claim, wherein the activated or transmuted target material comprises one or more positron emitting isotopes corresponding to one or more elements present in the target material.

10. Werkwijze volgens conclusie 9, waarbij elk positron emitterend isotoop in het geactiveerde of getransmuteerde doelmateriaal een verschillend temporeel vervalprofiel heeft en de snelheid waarmee elk positron emitterend isotoop vervalt en positronen emitteert afhankelijk is van de karakteristieke halfwaardetijd of levensduur.The method of claim 9, wherein each positron-emitting isotope in the activated or transmuted target material has a different temporal decay profile and the rate at which each positron-emitting isotope decays and emits positrons is dependent on its characteristic half-life or lifetime.

11. Werkwijze volgens conclusie 10, waarbij de werkwijze omvat het identificeren van een element gebaseerd op de fotonen die worden gedetecteerd in de detectietijdperiode en de temporele vervalprofielen van de positron emitterende isotopen.The method of claim 10, wherein the method comprises identifying an element based on the photons detected in the detection time period and the temporal decay profiles of the positron-emitting isotopes.

12. Werkwijze volgens een van de volgende conclusies, waarbij de werkwijze omvat het genereren van een gereconstrueerd 3D tomografisch beeld of tomogram gebaseerd op de fotonen die worden gedetecteerd in het detectietijdinterval, waarbij het gereconstrueerde 3D tomografisch beeld of tomogram indicatief of illustratief is voor de samenstelling van het doelmateriaal; en/of waarbij de werkwijze omvat het genereren van een 2D beeld gebaseerd op de fotonen die worden gedetecteerd in het detectietijdinterval, waarbij het gereconstrueerde 2D beeld illustratief is voor de samenstelling van het doelmateriaal.The method of any of the following claims, wherein the method comprises generating a reconstructed 3D tomographic image or tomogram based on the photons detected in the detection time interval, the reconstructed 3D tomographic image or tomogram being indicative or illustrative of the composition of the target material; and/or wherein the method comprises generating a 2D image based on the photons detected in the detection time interval, the reconstructed 2D image being illustrative of the composition of the target material.

13. Werkwijze volgens een van de voorgaande conclusies, waarbij de werkwijze omvat het detecteren van fotonen die worden geëmitteerdc, door middel van een geschikte detectoropstelling, en het bepalen van de samenstelling van het doelmateriaal door middel van één of meer processoren die communicerend zijn gekoppeld met de detectoropstelling teneinde detectorgegevens van de detectoropstelling die indicatief zijn voor de fotonen die worden gedetecteerd in het detectietijdinterval te ontvangen.A method according to any one of the preceding claims, wherein the method comprises detecting photons being emitted, by means of a suitable detector arrangement, and determining the composition of the target material by means of one or more processors communicatively coupled with the detector array to receive detector data from the detector array indicative of the photons detected in the detection time interval.

14. Werkwijze volgens conclusie 13, waarbij de werkwijze omvat het detecteren van fotonen op verschillende tijden gedurende het detectietijdinterval, waarbij de processor is geconfigureerd teneinde de detectorgegevens die gedurende het detectietijdinterval zijn ontvangen in een reeks van successieve tijdsegmenten te verwerken teneinde de samenstelling van het doelmateriaal te bepalen.The method of claim 13, wherein the method comprises detecting photons at different times during the detection time interval, the processor being configured to process the detector data received during the detection time interval in a series of successive time segments to determine the composition of the target material to decide.

15. Werkwijze volgens conclusie 13 of 14, waarbij de werkwijze omvat het ontleden van de detectorgegevens in een veelheid van exponentiële componenten teneinde relatieve concentraties van elementen in de samenstelling van het doelmateriaal te bepalen.The method of claim 13 or 14, wherein the method comprises parsing the detector data into a plurality of exponential components to determine relative concentrations of elements in the composition of the target material.

16. Werkwijze volgens een van de voorgaande conclusies, waarbij het doelmateriaal kool is, waarbij de stap van het bepalen van de samenstelling van de kool omvat het bepalen van een hoeveelheid zuurstof en/of koolstof die aanwezig is in het geactiveerde of getransmuteerde doelmateriaal gebaseerd op ten minste fotonen die temporeel worden gedetecteerd in het detectietijdinterval van positron emitterende isotopen van zuurstof en koolstof die aanwezig zijn in de kool als gevolg van fotonucleaire reacties tussen de fotonen in een vooraf bepaald energiebereik waarbij een GDR optreedt en zuurstof en koolstof in de kool, waarbij de werkwijze omvat het bepalen van een vochtgehalte en/of calorische waarde van de kool, of benaderingswaarden daarvan, waarbij de bepaalde hoeveelheid zuurstof gelieerd is aan het vochtgehalte van de kool, en de bepaalde hoeveelheid koolstof gelieerd is aan de calorische waarde van de kool.A method according to any preceding claim, wherein the target material is carbon, wherein the step of determining the composition of the carbon comprises determining an amount of oxygen and/or carbon present in the activated or transmuted target material based on at least photons detected temporally in the detection time interval of positron-emitting isotopes of oxygen and carbon present in the carbon as a result of photonuclear reactions between the photons in a predetermined energy range at which a GDR occurs and oxygen and carbon in the carbon, wherein the method comprises determining a moisture content and/or calorific value of the coal, or approximate values thereof, wherein the determined amount of oxygen is linked to the moisture content of the coal, and the determined amount of carbon is linked to the calorific value of the coal.

17. Werkwijze volgens een van de voorgaande conclusies, waarbij het detectietijdinterval is verbonden met een vervaltijdconstane van één of meer positron emitterende isotopen, corresponderend met één of meer elementen in het doelmateriaal.A method according to any preceding claim, wherein the detection time interval is associated with a decay time constant of one or more positron emitting isotopes, corresponding to one or more elements in the target material.

18. Werkwijze volgens conclusie 17, waarbij het detectietijdinterval is gekozen uit tussen één derde van de vervaltijdconstante tot drie keer de vervaltijdconstante van één of meer positron emitterende isotopen die corresponderen met één of meer elementen in het doelmateriaal.The method of claim 17, wherein the detection time interval is selected from between one third of the decay time constant to three times the decay time constant of one or more positron emitting isotopes corresponding to one or more elements in the target material.

19. Systeem voor het analyseren van materiaal, het systeem omvattende: een bestraling sinrichting die is geconfigureerd teneinde een doelmateriaal te bestralen met fotonen met een energie binnen een vooraf bepaald energiebereik waarbij een dipool reuzeresonantie (‘giant dipole resonance”) (GDR) optreedt teneinde het doelmateriaal te activeren of te transmuteren als gevolg van fotonucleaire reacties tussen de fotonen en één of meer elementen die aanwezig zijn in het doelmateriaal; een detectoropstelling die een detectiezone definieert die is geconfigureerd teneinde fotonen te detecteren met een vooraf bepaald energieniveau die zijn geëmitteerd uit het geactiveerd of getransmuteerd doelmateriaal dat zich bevindt in de detectiezone als gevolg van positronannihilatie in het geactiveerde of getransmuteerde doelmateriaal, waarbij de fotonen temporeel in een detectietijdinterval na bestraling worden gedetecteerd; een geheugeninrichting die gegevens opslaat; en ten minste één processor die communicerend is gekoppeld aan de detectoropstelling en de geheugenopslaginrichting, waarbij de één of meer processoren zijn geconfigureerd teneinde een samenstelling van het doelmateriaal te bepalen gebaseerd op ten minste detectorgegevens van de detectoropstelling die indicatief zijn voor de fotonen die temporeel in het detectietijdinterval door de detectoropstelling zijn gedetecteerd.A material analysis system, the system comprising: an irradiation device configured to irradiate a target material with photons having an energy within a predetermined energy range wherein a giant dipole resonance (GDR) occurs so as to activate or transmute the target material as a result of photonuclear reactions between the photons and one or more elements present in the target material; a detector arrangement defining a detection zone configured to detect photons of a predetermined energy level emitted from the activated or transmuted target material located in the detection zone as a result of positron annihilation in the activated or transmuted target material, wherein the photons are temporally in a detection time interval after irradiation are detected; a memory device that stores data; and at least one processor communicatively coupled to the detector array and the memory storage device, the one or more processors configured to determine a composition of the target material based on at least detector data from the detector array indicative of the photons temporally present in the detection time interval have been detected by the detector arrangement.

20. Systeem volgens conclusie 19, waarbij de ten minste ene processor is geconfigureerd teneinde de samenstelling van het doelmateriaal te bepalen door middel van het bepalen van een samenstelling van elementen van het doelmateriaal.The system of claim 19, wherein the at least one processor is configured to determine the composition of the target material by determining a composition of elements of the target material.

21. Systeem volgens conclusie 20, waarbij de samenstelling van elementen van het doelmateriaal wordt bepaald door het identificeren van een of meer elementen die aanwezig zijn in het doelmateriaal, in het bijzonder concentraties gebaseerd op fotonen die worden geëmitteerd door bijbehorende één of meer positron emitterende isotopen in het geactiveerde of getransmuteerde doelmateriaal gedurende het detectietijdinterval, indien dat al het geval is.The system of claim 20, wherein the composition of elements of the target material is determined by identifying one or more elements present in the target material, in particular concentrations based on photons emitted by associated one or more positron emitting isotopes in the activated or transmuted target material during the detection time interval, if any.

22. Systeem volgens conclusie 20 of 21, waarbij de ten minste ene processor is geconfigureerd teneinde de samenstelling van het doelmateriaal te bepalen door middel van het identificeren van een type molecuul in het doelmateriaal door middel van het correleren van de bepaalde samenstelling van elementen teneinde samenstellingen van elementen van moleculen te kennen.The system of claim 20 or 21, wherein the at least one processor is configured to determine the composition of the target material by identifying a type of molecule in the target material by correlating the determined composition of elements to determine compositions of elements of molecules.

23. Systeem volgens een van de conclusies 19 tot en met 22, waarbij het geactiveerd of getransmuteerd doelmateriaal één of meer positron emitterende isotopen omvat die corresponderen met één of meer elementen die aanwezig zijn in het doelmateriaal, waarbij elke positon emitterende isotoop in het geactiveerd of getransmuteerd doelmateriaal een verschillend temporeel vervalprofiel heeft en fotonen emitteert op verschillende tijden in het detectietijdinterval.The system of any one of claims 19 to 22, wherein the activated or transmuted target material comprises one or more positron emitting isotopes corresponding to one or more elements present in the target material, each positron emitting isotope in the activated or transmuted target material has a different temporal decay profile and emits photons at different times in the detection time interval.

24. Systeem volgens conclusie 23, waarbij de ten minste ene processor is geconfigureerd teneinde een element te identificeren op basis van de fotonen die worden gedetecteerd in de detectietijdperiode en de temporele vervalprofielen van de positron emitterende isotoop.The system of claim 23, wherein the at least one processor is configured to identify an element based on the photons detected in the detection time period and the temporal decay profiles of the positron-emitting isotope.

25. Systeem volgens een van de conclusies 19 tot en met 24, waarbij de detectoropstelling is geconfigureerd teneinde tegengestelde co-lineaire en/of samenvallende gammastraalfotonen van een vooraf bepaald energieniveau die worden geëmitteerd uit het geactiveerd of getransmuteerd doelmateriaal continu te detecteren gedurende het detectietijdinterval, waarbij de detectorgegevens ten minste tijdgemerkte energiegegevens omvatten die behoren bij het foton dat is gedetecteerd door de detectoropstelling.The system of any one of claims 19 to 24, wherein the detector arrangement is configured to continuously detect opposing co-linear and/or coincident gamma-ray photons of a predetermined energy level emitted from the activated or transmuted target material during the detection time interval, wherein the detector data includes at least time-marked energy data associated with the photon detected by the detector array.

26. Systeem volgens een van de conclusies 19 tot en met 25, waarbij de ten minste ene processor is geconfigureerd teneinde een gereconstrueerd 3D tomografisch beeld of tomogram gebaseerd op de fotonen die worden gedetecteerd in het detectietijdinterval te genereren, waarbij het gereconstrueerd 3D tomografisch beeld of tomogram illustratief is voor de samenstelling van het doelmateriaal; en/of waarbij de ten minste ene processor is geconfigureerd teneinde een 2D beeld te genereren gebaseerd op de fotonen die worden gedetecteerd in het detectietijdinterval, waarbij het gereconstrueerd 2D beeld illustratief is voor de samenstelling van het doelmateriaal.The system of any of claims 19 to 25, wherein the at least one processor is configured to generate a reconstructed 3D tomographic image or tomogram based on the photons detected in the detection time interval, the reconstructed 3D tomographic image or tomogram tomogram is illustrative of the composition of the target material; and/or wherein the at least one processor is configured to generate a 2D image based on the photons detected in the detection time interval, the reconstructed 2D image being illustrative of the composition of the target material.

27. Systeem volgens een van de conclusies 19 tot en met 26, waarbij de detectoropstelling is samengesteld teneinde fotonen te detecteren op verschillende tijden gedurende het tijdinterval, waarbij de ten minste ene processor is geconfigureerd teneinde de detectorgegevens die worden ontvangen gedurende het detectietijdinterval in een reeks van successieve tijdsegmenten te verwerken teneinde de samenstelling van het doelmateriaal te bepalen.The system of any one of claims 19 to 26, wherein the detector arrangement is configured to detect photons at different times during the time interval, the at least one processor configured to sequence the detector data received during the detection time interval. of successive time segments to determine the composition of the target material.

28. Systeem volgens een van de conclusies 19 tot en met 27, waarbij de ten minste ene processor is geconfigureerd teneinde de detectorgegevens omvattende detectiesignalen te ontleden in een veelheid van exponentiële componenten teneinde relatieve concentraties van elementen in de samenstelling van het doelmateriaal te bepalen.The system of any one of claims 19 to 27, wherein the at least one processor is configured to parse the detector data comprising detection signals into a plurality of exponential components to determine relative concentrations of elements in the composition of the target material.

29. Systeem volgens een van de conclusies 19 tot en met 28, waarbij de ten minste ene processor is geconfigureerd teneinde de samenstelling van het doelmateriaal te bepalen door middel van het vergelijken van de detectorgegevens met vooraf bepaalde detectorgegevens die zijn verbonden aan verschillende materialen.The system of any one of claims 19 to 28, wherein the at least one processor is configured to determine the composition of the target material by comparing the detector data with predetermined detector data associated with different materials.

30. Systeem volgens een van conclusies 19 tot en met 29, waarbij het detectietijdinterval is verbonden met een vervaltijdconstante van een of meer positron emitterende isotopen, corresponderend met één of meer elementen in het doelmateriaal.The system of any one of claims 19 to 29, wherein the detection time interval is associated with a decay time constant of one or more positron emitting isotopes, corresponding to one or more elements in the target material.

31. Systeem volgens conclusie 30, waarbij het detectietijdinterval is gekozen uit één derde van de vervaltijdconstante tot drie keer de vevaltijdconstante van één of meer positron emitterende isotopen, corresponderend met één of meer elementen in het doelmateriaal.The system of claim 30, wherein the detection time interval is selected from one third of the decay time constant to three times the decay time constant of one or more positron emitting isotopes, corresponding to one or more elements in the target material.

32. Systeem volgens een van de conclusies 19 tot en met 31, waarbij het doelmateriaal kool is, waarbij de processor is geconfigureerd teneinde de samenstelling van de kool te bepalen door middel van het bepalen van een hoeveelheid van zuurstof en/of koolstof die aanwezig is in het geactiveerd of getransmuteerd doelmateriaal, gebaseerd op ten minste fotonen die temporeel worden gedetecteerd in het detectietijdinterval van positron emitterende isotopen van zuurstof en koolstof die aanwezig zijn in het doelmateriaal als gevolg van fotonucleaire reacties tussen de fotonen in een vooraf bepaald energiebereik waarbij een GDR optreedt en zuurstof en koolstof in de kool, waarbij de processor is geconfigureerd teneinde een vochtgehalte en/of een calorische waarde van de kool te bepalen, of benaderingen daarvan, waarbij de bepaalde hoeveelheid zuurstof het vochtgehalte van de kool vertegenwoordigt, en de bepaalde hoeveelheid koolstof de calorische waarde van de kool vertegenwoordigt.The system of any of claims 19 to 31, wherein the target material is carbon, wherein the processor is configured to determine the composition of the carbon by determining an amount of oxygen and/or carbon present in the activated or transmuted target material, based on at least photons detected temporally in the detection time interval of positron-emitting isotopes of oxygen and carbon present in the target material as a result of photonuclear reactions between the photons in a predetermined energy range at which a GDR occurs and oxygen and carbon in the carbon, wherein the processor is configured to determine a moisture content and/or a calorific value of the carbon, or approximations thereof, wherein the determined amount of oxygen represents the moisture content of the carbon, and the determined amount of carbon represents the calorific value of the cabbage.

33. Permanent door een computer leesbaar medium waarop een permanente set van door een computer uitvoerbare instructies is opgeslagen, die, wanneer zij worden uitgevoerd op een of meer geschikte computers het volgende teweegbrengt: het ontvangen van detectorgegevens van een detectoropstelling die is verbonden met fotonen van een vooraf bepaald energieniveau die temporeel in een detectietijdinterval worden gedetecteerd door middel van een detectoropstelling van een geactiveerd of getransmuteerd doelmateriaal dat fotonen als gevolg van positronannihilatie in het materiaal emitteert; en het verwerken van de detectorgegevens teneinde een samenstelling van het doelmateriaal te bepalen ten minste op basis van detectorgegevens van de detectoropstelling die indicatief zijn voor de fotonen die temporeel in het detectietijdinterval zijn gedetecteerd door middel van de detectoropstelling.33. Permanent computer readable medium storing a permanent set of computer executable instructions which, when executed on one or more suitable computers, causes: receiving detector data from a detector array associated with photons of a predetermined energy level to be detected temporally in a detection time interval by means of a detector array of an activated or transmuted target material that emits photons due to positron annihilation in the material; and processing the detector data to determine a composition of the target material based at least on detector data from the detector array indicative of the photons detected temporally in the detection time interval by the detector array.

34. Werkwijze voor het analyseren van een doelmateriaal, de werkwijze omvattende:34. A method of analyzing a target material, the method comprising:

het ontvangen van detectorgegevens van een detectoropstelling die is verbonden met fotonen van een vooraf bepaald energieniveau die temporeel in een detectietijdinterval worden gedetecteerd door middel van een detectoropstelling van een geactiveerd of getransmuteerd doelmateriaal dat fotonen als gevolg van positronannihilatie in het materiaal emitteert; en het verwerken van de detectorgegevens teneinde een samenstelling van het doelmateriaal te bepalen ten minste op basis van detectorgegevens van de detectoropstelling die indicatief zijn voor de fotonen die temporeel in het detectietijdinterval zijn gedetecteerd door middel van de detectoropstelling.receiving detector data from a detector array associated with photons of a predetermined energy level detected temporally in a detection time interval by means of a detector array of an activated or transmuted target material that emits photons due to positron annihilation in the material; and processing the detector data to determine a composition of the target material based at least on detector data from the detector array indicative of the photons detected temporally in the detection time interval by the detector array.

35. Systeem voor het analyseren van materiaal, het systeem omvattende: een geheugeninrichting waarin gegevens worden opgeslagen; en ten minste één processor die communicerend is gekoppeld aan de geheugeninrichting, waarbij de ten minste ene processor is geconfigureerd teneinde: detectorgegevens te ontvangen van een detectoropstelling die is verbonden met fotonen van een vooraf bepaald energieniveau die temporeel in een detectietijdinterval worden gedetecteerd door middel van een detectoropstelling van een geactiveerd of getransmuteerd doelmateriaal dat fotonen als gevolg van positronannihilatie in het materiaal emitteert; en de detectorgegevens te verwerken teneinde een samenstelling van het doelmateriaal te bepalen ten minste op basis van detectorgegevens van de detectoropstelling die indicatief zijn voor de fotonen die temporeel in het detectietijdinterval zijn gedetecteerd door middel van de detectoropstelling.A material analyzing system, the system comprising: a memory device in which data is stored; and at least one processor communicatively coupled to the memory device, the at least one processor being configured to: receive detector data from a detector array associated with photons of a predetermined energy level detected temporally in a detection time interval by means of a detector arrangement of an activated or transmuted target material which emits photons as a result of positron annihilation in the material; and process the detector data to determine a composition of the target material based at least on detector data from the detector array indicative of the photons detected temporally in the detection time interval by the detector array.