Delay double-pulse laser spectrum method and system for measuring uranium polymetallic ore elements

Abstract

The embodiment of the invention relates to the technical field of spectral component detection, and discloses a delayed double-pulse laser spectroscopy method and system for measuring uranium polymetallic ore elements, the detection method is characterized in that a first laser beam and a second laser beam are sequentially emitted, the first laser beam is projected on a sample, and stoichiometric denudation can be performed on the sample to be detected; and then a second laser beam emitted in a delayed manner is projected above the denudated area of the detection sample, and particles formed by denudation are ionized by plasmas of the second laser beam, so that elements in the particles are subjected to energy level transition and radiate corresponding spectral lines. And collecting spectral lines to measure the element content of the uranium polymetallic ore. In the spectral line acquisition process, the image information of the laser denudation plume can be acquired through the image acquisition equipment, and then the relative position of the focal points of the first laser beam and the second laser beam is adjusted based on the image information, so that more particles denudated by the first laser beam enter the plasma of the second laser beam, and the detection precision can be improved.

Description

Technical Field

[0001] The embodiments of the present application relate to the technical field of spectral component detection, and in particular to a delayed double-pulse laser spectroscopy method and system for measuring uranium polymetallic ore elements. Background Art

[0002] Uranium resources are a scarce strategic mineral resource. The exploration and development of uranium polymetallic ores are of great significance and value to national defense security and civilian energy. Rapid and accurate determination of the content of uranium and associated elements is the key to achieving efficient utilization of these strategic mineral resources. Laser induced breakdown spectroscopy (LIBS) technology is a qualitative and quantitative analysis technology that has developed rapidly in recent years. It is simple and fast to pre-treat samples, analyze multiple elements simultaneously, and detect them in real time online. It can analyze almost all elements in the periodic table. Although LIBS technology has unparalleled advantages in the application of uranium ore detection, the matrix composition of uranium polymetallic ores is complex and there are many types of minerals. For example, uranium in the ore of the Huayangchuan uranium polymetallic deposit in Shaanxi Province is mainly present in the form of niobium titanite, crystalline uranium ore and pitchblende. Niobium appears in the form of niobium titanite. Zircon is the main form of rare metal zirconium, and contains uranium, thorium and rare earth elements. At the same time, heavy metal elements such as uranium, thorium, and rare earth have many extranuclear electrons. For example, U has 92 electrons, which are distributed at multiple energy levels and sub-energy levels. When excited, these electrons will undergo energy level transitions, and the transitions between the 5f, 6d, and 7s energy levels of uranium will radiate a series of complex spectral lines. Similarly, the electronic configuration of Th atoms is 6d 2 7s 2 , it can be seen that both the 5f shell and the 6d shell are not filled with electrons, and their energy level structures are complex. When analyzing Th using LIBS, after the sample is bombarded by laser, the atoms de-excite from the high excited state to the low excited state or the ground state. Due to the large number of de-excitation paths, the radiated spectrum is more complex. The electronic configuration and spectral terms of Th are nearly energy degenerate, making it difficult to distinguish and accurately identify the characteristic spectrum of each element in spectral analysis. Therefore, the existence of matrix effects and elemental spectral line interference will greatly increase the difficulty of LIBS quantitative analysis.

[0003] Therefore, it is necessary to develop a detection method and system that can quickly and accurately determine the content of uranium and associated elements in uranium polymetallic ores. Summary of the invention

[0004] A series of simplified concepts are introduced in the Summary of the Invention, which will be further described in detail in the Detailed Description of the Invention. This part of the invention does not mean to attempt to define the key features and essential technical features of the claimed technical solution, nor does it mean to attempt to determine the scope of protection of the claimed technical solution.

[0005] The present invention aims to solve at least one of the technical problems existing in the prior art or related art.

[0006] To this end, a first aspect of the present invention provides a delayed double-pulse laser spectroscopy method for measuring uranium polymetallic ore elements.

[0007] A second aspect of the present invention provides a delayed double-pulse laser spectroscopy system for measuring uranium polymetallic ore elements.

[0008] In view of this, according to a first aspect of an embodiment of the present application, a delayed double-pulse laser spectroscopy method for measuring uranium polymetallic ore elements is proposed, comprising: Step 101: Projecting a first laser beam onto a sample to be detected to perform chemical measurement ablation on the sample to be detected; Step 102: Projecting a second laser beam onto the ablated area of ​​the sample to be tested, the plasma generated by the second laser beam ionizes the particles induced by the first laser beam, so that the elements in the particles undergo energy level transitions and radiate corresponding spectral lines; Step 103: Acquire image information of the laser ablation feather based on an image acquisition device; Step 104: adjusting the relative positions of the focal points of the first laser beam and the second laser beam based on the image information; Step 105: Perform laser line scanning ablation sampling on the sample to be tested, collect spectrum lines, and determine the element content of the uranium polymetallic ore.

[0009] In a feasible implementation manner, the first laser beam is a femtosecond laser beam; and the second laser beam is a nanosecond laser beam.

[0010] In a feasible embodiment, before the step of projecting the first laser beam onto the sample to be detected and performing chemical measurement ablation on the sample to be detected, the method further includes: The uranium polymetallic ore sample is ground so that the particle size of the uranium polymetallic ore is normally distributed less than or equal to 8.31 μm, and the sample powder is tableted; wherein the tableting time is greater than or equal to 5 minutes and the pressure is greater than or equal to 20 tons.

[0011] In a feasible implementation, the step of projecting a second laser beam onto the ablated area of ​​the sample to be detected includes: After the first laser beam is emitted, a second laser beam is projected; The step of determining the time delay between the first laser beam and the second laser beam comprises: The first laser beam is detected by a photodetector, and the converted electrical signal is input into a broadband oscilloscope to obtain the first electrical signal peak value; The second laser beam is detected by a photodetector, and the converted electrical signal is input into a broadband oscilloscope to obtain a second electrical signal peak value; The time delay limit of the first laser beam and the second laser beam is determined based on the difference between the first electrical signal peak value and the second electrical signal peak value.

[0012] In a feasible implementation manner, the step of adjusting the relative positions of the focal points of the first laser beam and the second laser beam based on the image information includes: Analyzing the image information to obtain the evolution characteristics of the ablation plumes of the first laser beam and the second laser beam; The relative positions of the focal points of the first laser beam and the second laser beam are adjusted so that more particles formed by ablation enter the plasma generated by the second laser beam.

[0013] According to a second aspect of an embodiment of the present application, a delayed double-pulse laser spectroscopy system for measuring uranium polymetallic ore elements is proposed, which is used to implement the delayed double-pulse laser spectroscopy method for measuring uranium polymetallic ore elements as described in any of the above technical solutions. The detection system includes: A swing table, which is used to hold samples to be tested and drive the samples to be tested to be positioned; a first laser beam emitting assembly, the first laser beam emitting assembly being used to emit the first laser beam; a second laser beam sending component, the second laser beam sending component being used to send the second laser beam; An image acquisition device is used to acquire image information of the laser ablation feather.

[0014] In a feasible implementation, the first laser beam emitting assembly includes: a femtosecond laser, and a first half-wave plate, a first polarizing plate, a reflecting mirror, and a first focusing mirror sequentially arranged along an emitting path of the femtosecond laser.

[0015] In a feasible implementation, the second laser beam emitting assembly includes: a nanosecond laser, and a second half-wave plate, a second polarizer, and a second focusing mirror arranged in sequence along an emission path of the nanosecond laser.

[0016] In a feasible implementation manner, the delayed double-pulse laser spectroscopy system for measuring uranium polymetallic ore elements further includes: a spectrometer, wherein the spectrometer is used to collect spectral signals.

[0017] In a feasible embodiment, the delayed double-pulse laser spectroscopy system for measuring uranium polymetallic ore elements further comprises: A digital delay control generator is connected to the first laser beam emitting component, the second laser beam sending component, the spectrometer and the image acquisition device.

[0018] Compared with the prior art, the present invention has at least the following beneficial effects: The delayed double-pulse laser spectroscopy method for measuring the elements of uranium polymetallic ores provided in the embodiment of the present application successively emits a first laser beam and a second laser beam. The first laser beam is projected onto the sample, which will perform stoichiometric ablation on the sample to be detected, reducing the negative impact of the sample matrix effect; then the delayed second laser beam will be projected above the ablated area of ​​the detected sample, and the particles formed by the ablation of the first laser beam will be ionized by the plasma of the second laser beam, so that the elements in the particles undergo energy level transitions and radiate corresponding spectral lines. In this case, the spectral lines are collected to determine the element content of the uranium polymetallic ores. In the process of spectral line collection, the image information of the laser ablation plume can be collected by an image acquisition device, and then the positions of the first laser beam and the second laser beam are adjusted based on the image information, so that more particles ablated by the first laser are distributed in the plasma of the second laser beam, which can improve the detection accuracy.

[0019] The above description is only an overview of the technical solution of the present invention. In order to more clearly understand the technical means of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the present invention more obvious and easy to understand, the specific implementation methods of the present invention are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Various other advantages and benefits will become apparent to those of ordinary skill in the art by reading the detailed description of the preferred embodiments below. The accompanying drawings are only for the purpose of illustrating the preferred embodiments and are not to be considered as limiting the present application. Also, the same reference symbols are used throughout the accompanying drawings to represent the same components. In the accompanying drawings: Figure 1 A schematic flowchart of the steps of a delayed double-pulse laser spectroscopy method for measuring uranium polymetallic ore elements according to an embodiment of the present application; Figure 2 A timing control diagram of a delayed double-pulse laser spectroscopy method for measuring uranium polymetallic ore elements according to an embodiment of the present application; Figure 3 A schematic structural diagram of a delayed double-pulse laser spectroscopy system for measuring uranium and polymetallic ore elements according to an embodiment of the present application.

[0021] in, Figure 3 The corresponding relationship between the reference numerals and the component names is as follows: 210 a swing table, 220 a first laser beam emitting component, 230 a second laser beam emitting component, 240 an image acquisition device, 250 a spectrometer, 260 a digital delay control generator; 221 a first half-wave plate, 222 a first polarizing plate, 223 a reflecting mirror, 224 a first focusing mirror, 225 a femtosecond laser; 231 second half-wave plate, 232 second polarizing plate, 233 second focusing mirror, 234 nanosecond laser. DETAILED DESCRIPTION

[0022] In the following description, a large number of specific details are given to provide a more thorough understanding of the technical solutions provided by the present invention. However, it is obvious to those skilled in the art that the technical solutions provided by the present invention can be implemented without one or more of these details.

[0023] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should also be understood that when the terms "comprise" and / or "include" are used in this specification, it indicates the presence of features, integral bodies, steps, operations, elements and / or components, but does not exclude the presence or addition of one or more other features, integral bodies, steps, operations, elements, components and / or combinations thereof.

[0024] Now, exemplary embodiments according to the present invention will be described in more detail with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in a variety of different forms and should not be interpreted as being limited to the embodiments set forth herein. It should be understood that these embodiments are provided to make the disclosure of the present invention thorough and complete, and to fully convey the concept of these exemplary embodiments to those of ordinary skill in the art.

[0025] like Figure 1 As shown, according to the first aspect of the embodiment of the present application, a delayed double-pulse laser spectroscopy method for measuring uranium polymetallic ore elements is proposed, comprising: Step 101: Projecting a first laser beam onto a sample to be detected to perform chemical measurement ablation on the sample to be detected; Step 102: Projecting a second laser beam onto the ablated area of ​​the sample to be tested, the plasma generated by the second laser beam ionizes the particles induced by the first laser beam, so that the elements in the particles undergo energy level transitions and radiate corresponding spectral lines; Step 103: Acquire image information of the laser ablation feather based on an image acquisition device; Step 104: adjusting the relative positions of the focal points of the first laser beam and the second laser beam based on the image information; Step 105: Perform laser line scanning ablation sampling on the sample to be tested, collect spectrum lines, and determine the element content of the uranium polymetallic ore.

[0026] The delayed double-pulse laser spectroscopy method for measuring the elements of uranium polymetallic ores provided in the embodiment of the present application successively emits a first laser beam and a second laser beam. The first laser beam is projected onto the sample to perform stoichiometric ablation on the sample to be detected, and then the delayed second laser beam is projected above the ablated area of ​​the sample to be detected. The particles formed by the ablation of the first laser beam will be ionized by the plasma of the second laser beam, so that the elements in the particles undergo energy level transitions and radiate corresponding spectral lines. In this case, the element content of the uranium polymetallic ores can be determined by collecting spectral lines. In the process of collecting spectral lines, the image information of the laser ablation plume can be collected by an image acquisition device, and then the positions of the first laser beam and the second laser beam can be adjusted based on the image information, so that more particles ablated by the first laser are distributed in the plasma of the second laser beam, which can improve the detection accuracy.

[0027] The delayed double-pulse laser spectroscopy method for measuring the elements of uranium polymetallic ores provided in the embodiment of the present application is based on the non-confocal laser induced breakdown spectroscopy technology of the first laser beam and the second laser beam. The uranium polymetallic ores sample is scanned and ablated by the first laser beam, the negative impact of the sample matrix effect is reduced, and the uniformity and representativeness of the ablation area are improved. Then, the second laser beam causes energy level transitions of the elements in the particles and radiates corresponding spectral lines, thereby improving the intensity and stability of the laser induced breakdown spectroscopy signal, reducing the matrix effect in the analysis of uranium polymetallic ores, and enhancing the analysis accuracy. At the same time, the image information of the laser ablation plume is recorded by ultrafast imaging, which provides a new perspective for studying the mechanism of the influence of the uranium polymetallic ores matrix on the spectral signal. This technology can be widely used in the resource exploration of uranium polymetallic ores, the quality control of the nuclear fuel cycle, and the real-time and accurate analysis in the process of nuclear waste treatment. It has important industrial and scientific research value, and provides new technical support for the efficient use of uranium resources.

[0028] The delayed double-pulse laser spectroscopy method for measuring uranium polymetallic ore elements provided in the embodiment of the present application is intended to reduce the matrix effect in the analysis of uranium polymetallic ore samples and reveal its influence mechanism. Considering the complexity of the matrix of uranium polymetallic ore samples, the embodiment of the present application adopts ultrafast laser, such as femtosecond laser, and ablation can effectively reduce the ablation inhomogeneity caused by thermal expansion or non-uniform thermal diffusion of the matrix, thereby improving the accuracy and reproducibility of the analysis results; after the second laser beam is emitted, the excited atoms and ions of the plasma will undergo transitions and radiate specific spectral lines after being excited by the nanosecond laser. Based on this, by successively emitting the first laser beam and the second laser beam, the intensity of the spectral signal can be maximized, the influence of the matrix effect can be reduced, and more accurate and stable analysis results can be provided. Combined with the acquisition of image information by the image acquisition device, the spatial morphology of the double-pulse ablation plume (plasma, shock wave, ablation particles) at different times can be recorded synchronously or delayed, and the mechanism of the uranium polymetallic ore matrix affecting the spectral signal to varying degrees can be studied from the mesoscopic field.

[0029] The delayed double-pulse laser spectroscopy method for measuring elements in uranium polymetallic ores provided in the embodiments of the present application performs laser line scanning ablation sampling on the sample, collects spectral lines, and determines the element content of the uranium polymetallic ores. Based on this, a line scanning analysis test is performed on the uranium polymetallic ore cake sample, and the spectral signals induced by multiple laser pulses are superimposed, which helps to improve the element spectral resolution, collect element signals that are more representative, and the analysis results are more reliable.

[0030] In a feasible implementation manner, the first laser beam is a femtosecond laser beam; and the second laser beam is a nanosecond laser beam.

[0031] It can be understood that the first laser beam may also be other types of ultrafast lasers.

[0032] In this technical solution, the types of the first laser beam and the second laser beam are further provided. The first laser beam is a femtosecond laser beam. The extremely short time scale of the femtosecond pulse of the femtosecond laser beam (usually at the femtosecond level) makes the interaction time between the first laser beam and the sample extremely short. In this way, most of the laser energy of the first laser beam is used to directly evaporate or break down the material, rather than causing heat diffusion to the surrounding area, which can improve the uniformity and representativeness of the ablation area. The femtosecond laser can produce nanoscale sample microparticles without element fractionation effect, reducing the negative impact of the matrix effect. The second laser beam is a nanosecond laser beam. The selection of the nanosecond laser beam can efficiently ionize the sample nanoparticles and radiate the corresponding element spectrum.

[0033] In a feasible embodiment, before the step of projecting the first laser beam onto the sample to be tested and ablation of the sample to be tested, the method also includes: grinding the uranium polymetallic ore sample so that the normal distribution of the particle size of the uranium polymetallic ore is less than or equal to 8.31 μm, and tableting the sample powder; wherein the tableting time is greater than or equal to 5 minutes, and the pressure is greater than or equal to 20 tons.

[0034] In this technical solution, a sample preparation step is further provided before the first laser beam is projected, wherein the uranium polymetallic ore sample is fully ground to make the particle size of the uranium polymetallic ore sample small enough in normal distribution, and the sample powder is fully pressed into tablets, so that the element spectrum signal intensity of the sample detection is high and the repeatability is high. If the sample particle size is greater than 8.31 μm and the sample particles are not fully pressed into cakes, the element spectrum signal intensity will be low and the repeatability will be poor, making it difficult to find the element characteristic spectrum lines used for quantitative calculation of element content.

[0035] In a feasible embodiment, the step of projecting a second laser beam onto the ablated area of ​​the sample to be tested includes: projecting the second laser beam after the first laser beam is emitted; wherein, the step of determining the time delay between the first laser beam and the second laser beam includes: detecting the first laser beam through a photodetector, inputting the converted electrical signal into a broadband oscilloscope, and obtaining a first electrical signal peak; detecting the second laser beam through a photodetector, inputting the converted electrical signal into a broadband oscilloscope, and obtaining a second electrical signal peak; and determining the time delay limit of the first laser beam and the second laser beam based on the difference between the first electrical signal peak and the second electrical signal peak.

[0036] In this technical solution, the timing of the first laser beam and the second laser beam being emitted is further provided, and the first laser beam (femtosecond laser) and the second laser beam (nanosecond laser) need to be delayed and controlled. According to the plasma attenuation theoretical model, the plasma generated by the femtosecond laser is active in a short time, and the nanosecond laser needs to arrive within this time window to ensure that it effectively excites the plasma. If the delay is too long, the plasma will decay to a state where it cannot be excited, thereby greatly reducing the excitation effect. Therefore, it is crucial to accurately adjust the delay time of the femtosecond and nanosecond lasers. Based on this, the control method provided by the embodiment of the present application is used to obtain the laser pulses of the first laser beam and the second laser beam respectively, and then the converted electrical signal is input into a broadband oscilloscope, so that the first electrical signal peak and the second electrical signal peak can be obtained, and the difference between the first electrical signal peak and the second electrical signal peak can be obtained, and the time delay limit of the two laser pulses is determined. The timing of the second laser beam being emitted is determined based on the time delay limit of the two laser pulses, ensuring that the two laser beams interact in the optimal time window, fully exciting the plasma of different elements, and further improving the detection accuracy. It can be understood that if the delay is too long, the plasma will decay to a state where it cannot be excited, thereby greatly reducing the excitation effect. Therefore, it is very important to accurately adjust the delay time between the first laser beam and the second laser beam.

[0037] In some examples, the photodetector may be a high-speed response photodetector capable of quickly responding to a detected light signal to provide detection efficiency.

[0038] It is understandable that there also needs to be a time delay between the second laser beam and the spectrum acquisition. The first laser beam ablates the elements in the sample particles, and after being excited by the second nanosecond laser beam, it will undergo energy level transitions and radiate spectral lines of specific wavelengths, and the spectral signal intensity decays over time. Therefore, the time delay between the second laser beam and the spectrum acquisition also needs to be precisely controlled to capture the optimal spectral signal intensity.

[0039] In some examples, such as Figure 2 As shown, the timing control diagram is shown. Figure 2 Where t0 is the exposure start time of the image acquisition device, tend is the exposure end time of the image acquisition device, t fs is the time when the first laser beam is emitted, t ns The time for the second laser beam to be emitted can be controlled by the digital delay control generator (DG645) to control the pulse of the first laser beam, the pulse of the second laser beam, the detection light pulse, the CCD camera of the image acquisition device, and the start-up delay time of the spectrometer. The oscilloscope measures the delay time between light pulses, and the internal response time of the spectrometer and the CCD camera is known. The exposure time of the CCD camera is 300µs, covering the entire duration of the first laser beam inducing uranium polymetallic ore plasma and the second laser beam breaking down the plasma. The relative action time of the pulse of the first laser beam and the pulse of the second laser beam is adjusted to explore the influence on the atomic emission spectrum in the uranium polymetallic ore, and the start-up time of the ns detection light is adjusted to detect the morphological changes of each plasma shock wave.

[0040] In a feasible embodiment, the step of adjusting the relative position of the first laser beam and the second laser beam based on the image information includes: analyzing the image information to obtain the evolution characteristics of the erosion feathers of the first laser beam and the second laser beam; adjusting the relative position of the focus of the first laser beam and the second laser beam to allow more particles formed by erosion to enter the plasma generated by the second laser beam.

[0041] In this technical solution, specific steps for adjusting the relative positions of the two laser foci are further provided. The evolution characteristics of the erosion plume can be obtained through image information, and then the relative positions of the foci of the first laser beam and the second laser beam are adjusted to allow more particles to enter the plasma generated by the second laser beam, so that more particles are ionized by the plasma of the second laser, which can make the detection more representative.

[0042] like Figure 3 As shown, according to the second aspect of the embodiment of the present application, a delayed double-pulse laser spectroscopy system for measuring uranium polymetallic ore elements is proposed, which is used to implement the delayed double-pulse laser spectroscopy method for measuring uranium polymetallic ore elements as in any of the above technical solutions. The detection system includes: a swing table 210, the swing table 210 is used to hold the sample to be detected and drive the sample to be detected to be positioned; a first laser beam emitting component 220, the first laser beam emitting component 220 is used to emit a first laser beam; a second laser beam sending component, the second laser beam sending component is used to send a second laser beam; an image acquisition device 240, the image acquisition device 240 is used to obtain image information of the laser ablation plume.

[0043] The delayed double-pulse laser spectroscopy system for measuring uranium and polymetallic elements provided in the embodiments of the present application is used to implement the delayed double-pulse laser spectroscopy method for measuring uranium and polymetallic elements as described in any of the above-mentioned technical solutions. Therefore, the delayed double-pulse laser spectroscopy system for measuring uranium and polymetallic elements has all the beneficial effects of the delayed double-pulse laser spectroscopy method for measuring uranium and polymetallic elements as described in the above-mentioned technical solutions.

[0044] By using the delayed double-pulse laser spectroscopy system for measuring the elements of uranium polymetallic ore provided by the embodiment of the present application, the prepared sample is first placed on the swing table 210, and then the position of the sample is adjusted by the swing table 210, and then the first laser beam emitting component 220 is turned on, and the first laser beam emitting component 220 emits a first laser beam projected on the sample, which will perform stoichiometric ablation on the sample to be detected, and then the second laser beam delayed by the second laser beam sending component 230 will be projected above the ablated area of ​​the detection sample, and the particles formed by the ablation of the first laser beam will be ionized by the plasma of the second laser beam, so that the elements in the particles undergo energy level transitions and radiate corresponding spectral lines. In this case, the spectral lines are collected to determine the element content of the uranium polymetallic ore. In the process of spectral line collection, the image information of the laser ablation plume can be collected by the image acquisition device 240, and then the positions of the first laser beam and the second laser beam are adjusted based on the image information, so that more particles ablated by the first laser are distributed in the plasma of the second laser beam, which can improve the detection accuracy.

[0045] In some examples, the stage 210 may be a three-dimensional stage to facilitate adjusting the position of the sample.

[0046] like Figure 3 As shown, in a feasible implementation, the first laser beam emitting assembly 220 includes: a femtosecond laser 225 and a first half-wave plate 221 , a first polarizer 222 , a reflector 223 and a first focusing mirror arranged in sequence along the emission path of the femtosecond laser 225 .

[0047] In this technical solution, the structural composition of the first laser beam emitting component 220 is further provided. The first laser beam emitting component 220 may include a femtosecond laser 225 and a first half-wave plate 221, a first polarizer 222, a reflector 223 and a first focusing mirror arranged in sequence along the emission path of the femtosecond laser 225. The femtosecond laser 225 is used to emit a femtosecond laser. The first half-wave plate 221 and the first polarizer 222 are used to attenuate and regulate laser energy. The propagation direction of the femtosecond laser can be adjusted by the reflector 223 to facilitate the projection of the femtosecond laser onto the sample. Then, the light beam can be focused and projected onto the sample by the first focusing mirror, which is beneficial to chemical metrological ablation of the sample.

[0048] like Figure 3As shown, in a feasible implementation, the second laser beam emitting assembly includes: a nanosecond laser 234 and a second half-wave plate 231 , a second polarizer 232 , and a second focusing mirror 233 arranged in sequence along the emission path of the nanosecond laser 234 .

[0049] In the technical solution, the structural composition of the second laser beam emitting assembly is further provided, and the second laser beam emitting assembly may include a nanosecond laser 234, a second half-wave plate 231, a second polarizer 232, and a second focusing mirror 233. During use, the nanosecond laser 234 emits nanosecond laser light, the second half-wave plate 231 and the second polarizer 232 are used to attenuate and regulate the laser energy, and then the light beam can be focused and projected onto the sample through the second focusing mirror 233, which is conducive to the generation of plasma to ionize the particles induced by the first laser beam.

[0050] like Figure 3 As shown, in a feasible implementation, the delayed double-pulse laser spectroscopy system for measuring the elements of uranium polymetallic ore further includes: a spectrometer 250, and the spectrometer 250 is used to collect spectral signals. Such an arrangement facilitates the determination of the element content of uranium polymetallic ore.

[0051] It can be understood that the spectrometer 250 can be a high-resolution spectrometer, and the high-resolution spectrometer can be connected to a deep learning module. The deep learning module can perform data processing and optimization, which can further improve the detection efficiency.

[0052] like Figure 3 As shown, in a feasible embodiment, the delayed double-pulse laser spectroscopy system for measuring uranium polymetallic ore elements also includes: a digital delay control generator 260, connected to the first laser beam emitting component 220, the second laser beam sending component, the spectrometer 250 and the image acquisition device 240.

[0053] In this technical solution, the delayed double-pulse laser spectroscopy system for measuring uranium polymetallic ore elements may also include a digital delay control generator 260, through which the first laser beam emitting component 220, the second laser beam emitting component, the spectrometer 250 and the image acquisition device 240 may be controlled to work synchronously or asynchronously, so as to obtain the best double-pulse laser delay time, the acquisition time of the spectrometer 250 and the image information time of capturing the transient erosion feather morphology.

[0054] like Figure 3As shown, in some examples, the image acquisition device 240 may include a CCD camera, based on which the image acquisition device 240 can accurately record the dynamic process of delayed femtosecond-nanosecond double-pulse laser ablation of uranium polymetallic ore samples. The digital delay control generator 260 controls the delay time between the femtosecond laser 225, the nanosecond laser 234 and the flash lamp. The device can synchronously or delay the recording of the spatial morphology of the double-pulse ablation plume (plasma, shock wave, ablation particles) at different times, and study the mechanism of the uranium polymetallic ore matrix affecting the spectral signal to different degrees from the mesoscopic field.

[0055] In the present invention, the terms "first", "second", and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance; the term "plurality" refers to two or more, unless otherwise clearly defined. The terms "installed", "connected", "connected", "fixed", etc. should be understood in a broad sense. For example, "connected" can be a fixed connection, a detachable connection, or an integral connection; "connected" can be a direct connection or an indirect connection through an intermediate medium. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0056] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by terms such as “upper”, “lower”, “left”, “right”, “front” and “back” are based on the directions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or unit referred to must have a specific direction, be constructed and operated in a specific orientation, and therefore, cannot be understood as a limitation on the present invention.

[0057] In the description of this specification, the description of the terms "one embodiment", "some embodiments", "specific embodiments", etc. means that the specific features, structures, materials or characteristics described in conjunction with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representation of the above terms does not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described can be combined in any one or more embodiments or examples in a suitable manner.

[0058] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. For those skilled in the art, the present invention may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A delayed double-pulse laser spectroscopy method for measuring uranium polymetallic ore elements, characterized in that: include: Step 101: Projecting a first laser beam onto a sample to be detected to perform chemical measurement ablation on the sample to be detected; Step 102: Projecting a second laser beam onto the ablated area of ​​the sample to be tested, wherein the plasma generated by the second laser beam ionizes the particles induced by the first laser beam, so that the elements in the particles undergo energy level transitions and radiate corresponding spectral lines; Step 103: Acquire image information of the laser ablation feather based on an image acquisition device; Step 104: adjusting the relative positions of the focal points of the first laser beam and the second laser beam based on the image information; Step 105: Perform laser line scanning ablation sampling on the sample to be tested, collect spectrum lines, and determine the element content of the uranium polymetallic ore.

2. The delayed double-pulse laser spectroscopy method for measuring uranium polymetallic ore elements according to claim 1, characterized in that: The first laser beam is a femtosecond laser beam; The second laser beam is a nanosecond laser beam.

3. The delayed double-pulse laser spectroscopy method for measuring uranium polymetallic ore elements according to claim 1, characterized in that: Before the step of projecting the first laser beam onto the sample to be detected and performing chemical measurement ablation on the sample to be detected, the step further includes: The uranium polymetallic ore sample is ground so that the particle size of the uranium polymetallic ore is normally distributed less than or equal to 8.31 μm, and the sample powder is tableted; wherein the tableting time is greater than or equal to 5 minutes and the pressure is greater than or equal to 20 tons.

4. The delayed double-pulse laser spectroscopy method for measuring uranium polymetallic ore elements according to claim 1, characterized in that: The step of projecting a second laser beam onto the ablated area of ​​the sample to be detected comprises: After the first laser beam is emitted, projecting the second laser beam; Wherein, the step of determining the time delay between the first laser beam and the second laser beam comprises: The first laser beam is detected by a photodetector, and the converted electrical signal is input into a broadband oscilloscope to obtain a first electrical signal peak value; The second laser beam is detected by a photoelectric detector, and the converted electrical signal is input into a broadband oscilloscope to obtain a second electrical signal peak value; The time delay between the first laser beam and the second laser beam is determined based on the difference between the first electrical signal peak value and the second electrical signal peak value.

5. The delayed double-pulse laser spectroscopy method for measuring uranium polymetallic ore elements according to claim 1, characterized in that: The step of adjusting the relative positions of the focal points of the first laser beam and the second laser beam based on the image information comprises: Analyzing the image information to obtain the evolution characteristics of the ablation plumes of the first laser beam and the second laser beam; The relative positions of the focal points of the first laser beam and the second laser beam are adjusted so that more particles formed by ablation enter the plasma generated by the second laser beam.

6. A delayed double-pulse laser spectroscopy system for measuring uranium polymetallic ore elements, characterized in that: For implementing the delayed double-pulse laser spectroscopy method for measuring uranium polymetallic ore elements according to any one of claims 1 to 5, the detection system comprises: A swing table, which is used to hold samples to be tested and drive the samples to be tested to be positioned; a first laser beam emitting assembly, the first laser beam emitting assembly being used to emit the first laser beam; a second laser beam sending component, the second laser beam sending component being used to send the second laser beam; An image acquisition device is used to acquire image information of the laser ablation feather.

7. The delayed double-pulse laser spectroscopy system for measuring uranium polymetallic ore elements according to claim 6, characterized in that: The first laser beam emitting assembly comprises: a femtosecond laser, and a first half-wave plate, a first polarizing plate, a reflecting mirror and a first focusing mirror which are sequentially arranged along an emitting path of the femtosecond laser.

8. The delayed double-pulse laser spectroscopy system for measuring uranium polymetallic ore elements according to claim 6, characterized in that: The second laser beam emitting assembly includes: a nanosecond laser, and a second half-wave plate, a second polarizing plate, and a second focusing mirror arranged in sequence along the emitting path of the nanosecond laser.

9. The delayed double-pulse laser spectroscopy system for measuring uranium polymetallic ore elements according to claim 6, characterized in that: Also includes: A spectrometer is used to collect spectral signals.

10. The delayed double-pulse laser spectroscopy system for measuring uranium polymetallic ore elements according to claim 9, characterized in that: Also includes: A digital delay control generator is connected to the first laser beam emitting component, the second laser beam sending component, the spectrometer and the image acquisition device.

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