Railway roadbed filler sulfur content detection device and method

Abstract

The present invention relates to a device and method for detecting the sulfur content of railway roadbed fillers, and relates to the technical field of sulfur content detection in roadbeds, and is used to solve the problems of difficulty in on-site detection of the sulfur content of railway roadbed fillers and insufficient detection accuracy. The detection device provided by the present invention includes an Rh target X-ray tube, a diffraction crystal, a spin sample stage, an optical path fixing device and a detector; the X-rays emitted by the X-ray tube are diffracted by the diffraction crystal to generate diffraction rays as a primary target to irradiate the sample surface, and at the same time, the diffraction crystal is excited to generate element characteristic X-ray fluorescence as a secondary target to irradiate the sample surface. The continuous scattered line background is greatly reduced by monochromatizing the X-rays, the signal-to-noise ratio of the element characteristic X-ray fluorescence is improved, the element characteristic X-ray fluorescence of different energy segments is excited in sections and efficiently, and the excitation of the Ca element is suppressed; combined with the multivariate nonlinear overlapping regression algorithm, the detection limit of the S element is reduced, and the rapid and accurate determination of the sulfur content under the conditions of different roadbed sample element contents is met.

Description

Technical Field

[0001] The invention relates to the technical field of sulfur content detection in roadbed, and in particular to a device and method for detecting the sulfur content of railway roadbed filler. Background Art

[0002] The sulfur content in the roadbed soil has an important impact on the road surface arching. The main element in the roadbed soil is calcium, which usually contains several tens of percent; sulfur is a trace element, which usually contains 0.01%-5%. Once the sulfur content is too high, it may cause the road base to expand and crack. Therefore, it is of great significance to master the sulfur content in the roadbed material.

[0003] The standard method for determining sulfur content is the gravimetric method (combustion method). This method is simple to operate and accurate, but requires a long time for firing and cooling, and has a long analysis cycle, which cannot meet the requirements of on-site use.

[0004] HJ780-2015 "Wavelength dispersive X-ray fluorescence spectrometry for determination of inorganic elements in soil and sediment" stipulates the wavelength dispersive X-ray fluorescence spectrometry for analyzing soil inorganic elements, including the determination of sulfur, using the tablet method, which is simple to operate and fast to analyze. However, there are matrix interference and elemental spectral interference in the element content analysis of X-ray fluorescence spectrometry. In the XRF analysis of roadbed samples, due to the high content of Ca in the sample, and Ca:K b The escape peak of 4.01keV in the energy detector (SDD) is 2.27keV, which is consistent with the S:K a 2.31keV overlap. In addition to the overlapping interference of spectral peaks, there is also the matrix absorption effect, which makes it difficult to determine the trace sulfur content in roadbed samples. Therefore, this analysis method can only be applied to soil matrices with high silica content and low Ca content; while the content of Ca and Si in roadbed soil may be high, and the relative content range of Ca and Si is uncertain. Therefore, the existing standard method has a poor detection limit for sulfur, which cannot meet the requirements for trace sulfur analysis in roadbed samples, nor can it meet the determination of sulfur in roadbed materials with large matrix differences. Summary of the invention

[0005] The invention provides a device and method for detecting the sulfur content of railway roadbed filling material, which are used to solve the problems of difficulty in on-site detection of the sulfur content of railway roadbed filling material and insufficient detection accuracy.

[0006] The invention provides a device for detecting the sulfur content of railway roadbed filler, comprising an X-ray tube, a diffraction crystal, a spin sample stage, an optical path fixing device and a detector; the X-ray tube is an Rh target X-ray tube using an Rh target material; the diffraction crystal is a fully focusing hyperbolic curved crystal prepared using a Ge (111) crystal; the X-rays emitted by the X-ray tube are diffracted by the diffraction crystal to generate diffraction rays, and the diffraction crystal is simultaneously excited to generate element characteristic X-ray fluorescence; the diffraction rays and the element characteristic X-ray fluorescence are used to irradiate a sample on the spin sample stage for detection; the optical path fixing device is used to adjust and fix the position and angle of the diffraction crystal, thereby effectively improving the excitation efficiency of the sulfur element.

[0007] By using a Rh target X-ray tube and a fully focused hyperboloidal curved crystal prepared from a Ge(111) crystal, the Rh:L a 2.70keV single energy ray diffracts and focuses on the sample spot (i.e. the measurement point), Rh:L a The energy of the radiation has a high excitation efficiency for light elements. At the same time, the emission spectrum of the Rh target X-ray tube excites the element characteristic X-ray fluorescence of the Ge(111) crystal. The element characteristic X-ray fluorescence of the excited Ge(111) simultaneously serves as a secondary target to irradiate the sample surface. The monochromatic diffraction excitation eliminates the background interference of the scattered rays generated by the sample in the emission spectrum of the X-ray tube, and efficiently excites the element characteristic X-ray fluorescence of different energy segments in sections, suppresses the excitation of some elements, such as Ca, thereby reducing the detection limit of sulfur and improving the accuracy of detection.

[0008] In one embodiment, the diffracted ray is a monochromatic diffraction ray Rh:L a 2.70keV rays, the characteristic X-ray fluorescence of the element is Ge:K a 9.88keV, Ge:K b 10.98keV element characteristic X-ray fluorescence. Segmented and efficient excitation of element characteristic X-ray fluorescence in different energy ranges, Rh:L a 2.70keV rays can efficiently excite S and suppress the excitation of Ca elements, thereby reducing the detection limit of sulfur and improving the accuracy of detection.

[0009] In one embodiment, it also includes a crystal adjustment mechanism, which is used to adjust the installation position of the diffraction crystal to meet the Bragg diffraction conditions and improve the excitation efficiency of the sulfur element.

[0010] In one embodiment, a sample changing component is further included. The sample changing component is arranged at the bottom of the sample stage. The sample changing component moves up and down to drive the spin sample stage to leave the sample measuring position, so that sample replacement can be facilitated.

[0011] In one embodiment, the spin sample stage further comprises a spin component and a sample stage, wherein the spin component is used to connect and drive the sample stage to rotate. When testing the sample, the spin component can drive the sample stage and the sample thereon to rotate, thereby ensuring the uniformity of the irradiated sample and the accuracy of the test.

[0012] The present invention also provides a method for detecting the sulfur content of railway roadbed filler, which uses the above-mentioned detection device to detect the sulfur content of railway roadbed filler.

[0013] There are matrix interference and element line interference in the element content analysis of X-ray fluorescence spectrometry. In the XRF analysis of roadbed samples, due to the high content of Ca in the samples, the Ca:K b The escape peak of 4.01keV in the energy detector (SDD) is 2.27keV, which is consistent with the S:K a 2.31keV overlap, which results in the characteristic X-ray fluorescence intensity detected by the detector not being entirely contributed by the sulfur element, so a special algorithm must be used to accurately correct the influence of the calcium escape peak. In addition to the overlapping interference of spectral peaks, there is also a matrix absorption effect. For example, the characteristic X-ray fluorescence intensity of the same content of sulfur elements in different silicon-based, calcium-based or silicon-calcium mixed-based rocks will also lead to different intensities due to different matrices. Therefore, the influence of different matrices on the characteristic X-ray fluorescence intensity of sulfur elements must also be corrected or eliminated using a special algorithm. Different matrices, element spectral line interference, etc. all cause difficulties in the determination of trace sulfur content in roadbed samples. If the above-mentioned influencing factors are not considered, it is impossible to eliminate or correct the above-mentioned effects by only using the traditional simple linear regression of intensity and content, which will lead to erroneous detection results and give erroneous judgments. The present invention adopts a multivariate nonlinear overlapping regression algorithm, establishes the influence coefficient between elements and the correction equation through a large number of sample analyses, and obtains the influence factors of different matrices and spectral line overlap interference for elimination or correction, thereby obtaining a quantitative result with higher accuracy.

[0014] In one embodiment, the method for detecting the sulfur content of railway roadbed filler comprises the following steps:

[0015] Prepare a standard sample containing sulfur and calcium, and measure the standard sample using the detection device to obtain the counting rate intensity of sulfur in the standard sample, Ca:K a Line count rate intensity and Ca:K b Line count rate intensity;

[0016] According to the counting rate intensity of sulfur element, Ca:K a Line count rate intensity and Ca:K b Line count rate intensity, calculated using the multivariate nonlinear overlapping regression algorithm to obtain the calculated intensity of sulfur in the standard sample;

[0017] The sulfur calibration curve is established with the percentage of sulfur in the standard sample as the horizontal axis and the calculated intensity of sulfur in the standard sample as the vertical axis.

[0018] The detection device is used to measure the railway roadbed filler sample to obtain the count rate intensity of sulfur element, Ca:K a Line count rate intensity and Ca:K b Line count rate intensity;

[0019] According to the counting rate intensity of sulfur element, Ca:K a Line count rate intensity and Ca:K b Line count rate intensity, calculated using the multivariate nonlinear overlapping regression algorithm formula to obtain the calculated intensity of sulfur in the filler sample;

[0020] The corrected content of sulfur in the filler sample is obtained by calculation based on the calculated intensity of sulfur in the filler sample and the calibration curve.

[0021] The present invention combines monochromatic X-ray fluorescence spectroscopy with a multivariate nonlinear overlapping regression algorithm, that is, taking into account a variety of influencing factors, to meet the requirements of rapid and accurate determination of sulfur content under conditions of different roadbed sample element contents.

[0022] In one embodiment, the multivariate nonlinear overlapping regression algorithm formula is:

[0023] S2=((S1+3)×0.803)×(C1+C2),

[0024] Among them, S2 is the calculated intensity of sulfur, S1 is the count rate intensity of sulfur, and C1 is Ca:K a Line count rate intensity, C2 is Ca:K b Line count rate intensity.

[0025] In one embodiment, the calibration curve is:

[0026] S0=(A1× S2)+A0,

[0027] Where: S0 is the corrected content of sulfur element, S2 is the calculated intensity of sulfur element, A1 is the slope of the calibration curve, and A0 is the intercept of the calibration curve.

[0028] In one embodiment, the standard sample includes a matrix and sulfur element added to the matrix, and the matrix is ​​pure CaCO3 or a mixture of CaCO3 and SiO2.

[0029] Compared with the prior art, the advantages of the present invention are that the present invention adopts a fully focused hyperbolic curved crystal prepared by a Rh target X-ray tube and a Ge (111) crystal, and the fully focused hyperbolic curved crystal prepared by the Ge (111) crystal meets the Bragg condition and is arranged on the Rowland circle from the exit point of the Rh target X-ray tube to the focal point of the sample, and the monochromatic diffraction Rh:L a 2.70keV rays, the Rh target X-ray tube emits Rh:L a The 2.70keV single energy ray diffracts and focuses on the sample spot. At the same time, the emission spectrum of the Rh target X-ray tube excites the elemental characteristic X-ray fluorescence of the Ge(111) crystal. The excited Ge:K a 9.88keV and Ge:K b The 10.98keV element characteristic X-ray fluorescence also serves as a secondary target to irradiate the sample surface. The X-ray incident on the sample includes Rh:L a 2.70keV, Ge:K a 9.88keV, Ge:K b 10.98keV monochromatic X-ray. The railway roadbed filler sulfur content detection device of the present invention greatly reduces (or even eliminates) the continuous scattered line background, greatly improves the signal-to-noise ratio of element characteristic X-ray fluorescence, and efficiently excites element characteristic X-ray fluorescence in different energy segments in sections, suppressing the excitation of some elements, such as Ca.

[0030] The invention breaks through the simple linear regression of traditional intensity and content by combining monochromatic X-ray fluorescence spectroscopy with a multivariate nonlinear overlapping regression algorithm, and adopts a multivariate nonlinear overlapping regression algorithm to eliminate and correct the influence of interferences of different matrices and spectral lines, so as to achieve accurate quantification of characteristic X-ray fluorescence intensity and content of sulfur element; adopts a hyperbolic curved crystal for monochromatic excitation to reduce the detection limit of S, so as to achieve accurate quantification of low-content sulfur element; combines the hyperbolic curved crystal and the multivariate nonlinear overlapping algorithm to cope with different types of roadbed materials, has wider adaptability, fast nondestructive detection, low cost, and meets the requirements of fast and accurate determination of sulfur content under conditions of different roadbed sample element contents. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Hereinafter, the present invention will be described in more detail based on embodiments and with reference to the accompanying drawings.

[0032] Figure 1 2 is a schematic structural diagram of a device for detecting sulfur content in railway roadbed filler in an embodiment of the present invention;

[0033] Figure 2 Schematic diagram of the optical path of the device for detecting the sulfur content of railway roadbed filler in an embodiment of the present invention;

[0034] Figure 3 is the Rh target X-ray tube emission spectrum and Rh:La Monochromatize the incident spectrum.

[0035] Reference numerals:

[0036] 1. X-ray tube; 2. Air inlet; 3. Sealed cavity; 4. Diffraction crystal; 5. Crystal adjustment knob; 6. Detector; 7. Sample stage; 8. Lip seal; 9. Spinning component; 10. Sample changing assembly; 11. Sample measurement point; 12. Rh target; 13. Optical path fixing device; 14. Sample. DETAILED DESCRIPTION

[0037] In order to make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be clearly and completely described below.

[0038] In the description of this specification, the description with reference to the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples" 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 representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials or characteristics described may be combined in any one or more embodiments or examples in a suitable manner. In addition, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples, without contradiction.

[0039] The words "first", "second" and similar terms used in the present disclosure are only used for descriptive purposes and do not indicate any order, quantity or importance, but are only used to distinguish different parts. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of the features. In the description of the present invention, the meaning of "multiple" is at least two, such as two, three, etc., unless otherwise clearly and specifically defined. Words such as "include" or "comprise" mean that the elements before the word include the elements listed after the word, and do not exclude the possibility of also covering other elements. "Up", "down", "left", "right" and the like are only used to indicate relative positional relationships. When the absolute position of the described object changes, the relative positional relationship may also change accordingly.

[0040] In the present disclosure, when a specific device is described as being located between a first device and a second device, there may or may not be an intermediate device between the specific device and the first device or the second device. When a specific device is described as being connected to other devices, the specific device may be directly connected to the other device without an intermediate device, or may not be directly connected to the other device but have an intermediate device.

[0041] All terms (including technical terms or scientific terms) used in the present disclosure have the same meanings as those understood by ordinary technicians in the field to which the present disclosure belongs, unless otherwise specifically defined. It should also be understood that terms defined in general dictionaries, such as general dictionaries, should be interpreted as having meanings consistent with their meanings in the context of the relevant technology, and should not be interpreted in an idealized or extremely formal sense, unless explicitly defined herein.

[0042] like Figure 1 , Figure 2 As shown, the present invention provides a device for detecting the sulfur content of railway roadbed filler, which is mainly composed of an X-ray tube 1, a diffraction crystal 4, a spinning sample stage, an optical path fixing device, a detector 6 and a sealed cavity 3. The sealed cavity 3 has a closed space, which is a vacuum space, a helium-filled space or a hydrogen-filled space. The X-ray tube 1 is fixed on one side of the sealed cavity 3, and the detector 6 is fixed on the other side of the sealed cavity 3. The spinning sample stage includes a sample stage 7 and a spinning component 9 for driving the sample stage to rotate. The sample stage 7 and the diffraction crystal 4 are fixed in the sealed cavity 3, so that the optical path and the sample 14 are in a vacuum or atmosphere protection to ensure the accuracy of the test. The detector 6 is preferably a semiconductor detector SDD. The X-ray tube 1 is an Rh target X-ray tube using an Rh target material, and preferably, the Rh target X-ray tube is a micro-focus spot Rh target X-ray tube. The diffraction crystal 4 is a fully focusing hyperbolic curved crystal prepared using Ge (111) crystal. The X-rays emitted by the X-ray tube 1 are diffracted by the diffraction crystal 4 to generate diffraction rays, and at the same time excite the diffraction crystal 4 to generate element characteristic X-ray fluorescence; the diffraction rays and crystal element characteristic X-ray fluorescence are used to irradiate the sample 14 on the sample stage 7 for detection.

[0043] By using a Rh target X-ray tube and a fully focused hyperbolic curved crystal prepared by a Ge (111) crystal, the fully focused hyperbolic curved crystal prepared by the Ge (111) crystal meets the Bragg diffraction condition and is arranged on the Rowland circle from the exit point of the Rh target X-ray tube to the focusing point of the sample 14, and the Rh:L emitted by the Rh target X-ray tube is a The 2.70keV single energy ray is diffracted and focused to the sample spot (i.e., the sample point 11), stimulating the characteristic X-ray of the sample, which is received by the detector 6 and the element content of the sample is analyzed. The Rh:L emitted by the full-focusing hyperbolic curved crystal diffraction Rh target X-ray tube made of Ge (111) crystal a , adjust the crystal adjustment knob 5 so that the diffraction Rh:L a The diffraction efficiency is maximized, Rh:L a The ray energy has a high excitation efficiency for light elements, Rh:L a2.70keV rays can efficiently excite S elements and suppress the excitation of Ca elements, thereby reducing the detection limit of sulfur and improving the accuracy of detection. Monochromatic diffraction excitation eliminates the background interference of scattered rays generated by the sample in the X-ray tube emission spectrum. The use of hyperbolic curved crystal monochromatic excitation technology greatly improves the signal-to-noise ratio of element characteristic X-ray fluorescence and the element peak-to-background ratio (see Figure 3 ). At the same time, the emission spectrum of the Rh target X-ray tube excites the elemental characteristic X-ray fluorescence of the Ge(111) crystal. The elemental characteristic X-ray fluorescence of Ge(111) after being excited also serves as a secondary target to irradiate the surface of sample 14. The X-ray incident on sample 14 includes Rh:L a 2.70keV, Ge:K a 9.88keV, Ge:K b 10.98keV monochromatic X-rays greatly reduce (or even eliminate) the background of continuous scattered rays, greatly improve the signal-to-noise ratio of element characteristic X-ray fluorescence, efficiently excite element characteristic X-ray fluorescence in different energy segments in sections, suppress the excitation of some elements, such as Ca, thereby reducing the detection limit of sulfur and improving the accuracy of detection. When testing the sample 14, the spin component 9 can drive the sample stage 7 and the sample 14 thereon to rotate, ensuring the uniformity of the irradiated sample 14 and the accuracy of the test.

[0044] In some embodiments, a crystal adjustment mechanism is further provided, which may be a crystal adjustment knob 5 installed on the sealed cavity 3. By rotating the crystal adjustment knob 5, the initially installed crystal can be adjusted to ensure that the crystal is in a theoretical position to meet the Bragg diffraction condition. For example, by rotating the crystal adjustment knob 5, the outgoing X-rays of the Rh target X-ray tube 1 are incident on the diffraction crystal 4 at an incident angle of 44.68°, and the diffraction crystal 4 diffracts to generate a monochromatic diffraction Rh:L a 2.70keV rays, simultaneously exciting the diffraction crystal 4 to emit Ge:K a 9.88keV, Ge:K b 10.98keV element characteristic X-ray fluorescence, after adjustment, tighten the optical path fixing device 13 to fix the position and angle of the diffraction crystal, so that the optical path system is stable, ensuring that the instrument optical path is stable at the best diffraction efficiency to excite sulfur element, and at the same time, it is convenient to carry the instrument and effectively prevent shock.

[0045] In some embodiments, a sample changing component 10 is also provided, and the sample changing component 10 is fixed below the sealed cavity 3, and the sample table 7 is provided on the top of the sample changing component 10, and the pressed sample 14 is placed on the sample table 7. The sample changing component 10 moves up and down to drive the sample table 7 and the sample 14 to leave the sampling position for sample 14 replacement.

[0046] In some embodiments, the sealed cavity 3 is further provided with a lip seal 8 and an air inlet 2. The spin component 9 and the sealed cavity 3 can be sealed by the lip seal 8; when the enclosed space is a helium-filled space or a hydrogen-filled space, the air inlet 2 is used to add helium or hydrogen to the enclosed space; when the enclosed space is a helium-filled space or a vacuum space, the air inlet 2 is used to evacuate. By providing the lip seal 8 and the air inlet 2, it is ensured that the test atmosphere is vacuum or atmosphere protection.

[0047] The present invention also provides a method for detecting the sulfur content of railway roadbed filler, which uses a detection device for detection and a multivariate nonlinear overlapping regression algorithm to calculate the sulfur content of the railway roadbed filler, wherein the multivariate refers to the counting rate intensity of sulfur element, Ca:K a Line count rate intensity, Ca:K b Line count rate intensity and calculated intensity of sulfur element; the formula of multivariate nonlinear overlapping regression algorithm is: S2=((S1+3)×0.803)×(C1+C2), where S2 is the calculated intensity of sulfur element, S1 is the count rate intensity of sulfur element, C1 is Ca:K a Line count rate intensity, C2 is Ca:K b Line count rate intensity; the overlap algorithm is to obtain the counting intensity of sulfur element and then recalibrate, with the percentage of sulfur element in the standard sample as the horizontal coordinate and the calculated intensity of sulfur element in the standard sample as the vertical coordinate, to establish a calibration curve of sulfur element, the calibration curve is: S0=(A1×S2)+A0, where S0 is the calibration content of sulfur element, A1 is the slope of the calibration curve, A0 is the intercept of the calibration curve, and S2 is the calculated intensity of sulfur element. The method for detecting sulfur content in railway roadbed filler can specifically include the following steps:

[0048] Step 1: Prepare a standard sample containing sulfur and calcium elements, and measure the standard sample through a detection device to obtain the counting rate intensity of sulfur element in the standard sample, Ca:K a Line count rate intensity and Ca:K b Line count rate intensity.

[0049] Since the main element in roadbed soil is calcium, the content is usually several tens of percent; sulfur is a trace element, the content is usually in the range of 0.01%-5%; and Ca:K b The 4.01keV escape peak is Ca:K b -E2.27keV, with S:K a 2.31keV cannot be resolved by detector 6, thus affecting the detection limit of sulfur element and spectrum analysis.

[0050] In order to cope with different matrix types of roadbed materials, different matrix types such as pure CaCO3, CaCO3:SiO2=3:1, CaCO3:SiO2=1:1, and CaCO3:SiO2=1:3 were prepared. Different contents of sulfur were added to different matrix materials to obtain standard samples, thereby verifying the adaptability of the multivariate nonlinear overlapping regression algorithm.

[0051] The main influencing factors of S test are the fluorescence intensity of S, the intensity of Ca and the intensity of SiO2. Through principal component analysis, it is found that the main influencing factors are the intensity of S and the intensity of Ca. Therefore, it can be simplified to only consider the relationship between the fluorescence intensity of S and Ca. That is, the determination of S content is mainly caused by the Ca content, and has little influence on other factors. This may be because Ca:K b The escape peak energy is 2.27keV, which is similar to S:K a There are more overlaps at 2.31keV, which also increases the adaptability of the regression model, whether it is dealing with Ca+Si matrix or other main matrix types.

[0052] Step 2: Based on the counting rate intensity of sulfur element, Ca:K in the standard sample a Line count rate intensity and Ca:K b The line count rate intensity is calculated by the multivariate nonlinear overlapping regression algorithm formula to obtain the calculated intensity of sulfur element in the standard sample. The multivariate nonlinear overlapping regression algorithm formula is:

[0053] S2=((S1+3)×0.803)×(C1+C2),

[0054] Among them, S2 is the calculated intensity of sulfur, S1 is the count rate intensity of sulfur, and C1 is Ca:K a Line count rate intensity, C2 is Ca:K b Line count rate intensity.

[0055] Step 3: Establish a calibration curve for sulfur with the percentage of sulfur in the standard sample as the horizontal axis and the calculated intensity of sulfur in the standard sample as the vertical axis.

[0056] Step 4: Measure the railway roadbed filler sample through the detection device to obtain the counting rate intensity of sulfur element in the filler sample, Ca:K a Line count rate intensity and Ca:K b Line count rate intensity.

[0057] Step 5: Based on the count rate intensity of sulfur element, Ca:K in the filler sample obtained in step 4 a Line count rate intensity and Ca:K bThe line count rate intensity is calculated by the multivariate nonlinear overlapping regression algorithm formula to obtain the calculated intensity of sulfur element in the filler sample.

[0058] Step 6: According to the calculated intensity of sulfur in the filler sample, the corrected content of sulfur in the filler sample is calculated through the calibration curve. Specifically, the calculated intensity of sulfur in the filler sample obtained in step 5 is substituted into the calibration curve to calculate the corrected content of sulfur in the filler sample. The calibration curve is:

[0059] S0=(A1×S2)+A0,

[0060] Wherein: S0 is the corrected content of sulfur element, A1 is the slope of the calibration curve, A0 is the intercept of the calibration curve, and S2 is the calculated intensity of sulfur element.

[0061] The multivariate nonlinear overlapping regression algorithm formula and calibration curve are used to establish the influence coefficient between elements and the calibration curve through the analysis of a large number of samples, so as to obtain quantitative results with higher accuracy.

[0062] Table 1 shows the S determination results under different matrix conditions, and Table 2 shows the S recalibration results after considering the Ca test results. For filler samples with sulfur content S < 0.1%, the relative deviation is controlled at 30%; for filler samples with sulfur content ≥ 0.1%, the relative deviation is controlled at 25%, which meets the quality control requirements for rapid quantitative analysis of sulfur content in railway subgrade fillers.

[0063] Table 1: S determination results under different matrix conditions

[0064]

[0065] Table 2: S recalibration results after considering Ca test results

[0066]

[0067] Although the present invention has been described with reference to preferred embodiments, various modifications may be made thereto and parts thereof may be replaced by equivalents without departing from the scope of the present invention. In particular, the various technical features mentioned in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present invention is not limited to the specific embodiments disclosed herein, but includes all technical solutions falling within the scope of the claims.

Claims

1. A device for detecting sulfur content in railway roadbed filler, characterized in that: The invention comprises an X-ray tube, a diffraction crystal, a spin sample stage, an optical path fixing device and a detector; the X-ray tube is an Rh target X-ray tube using an Rh target material; the diffraction crystal is a fully focusing hyperboloidal curved crystal prepared using a Ge (111) crystal; the X-rays emitted by the X-ray tube are diffracted by the diffraction crystal to generate diffraction rays, and the diffraction crystal is excited to generate element characteristic X-ray fluorescence at the same time; the diffraction rays and the element characteristic X-ray fluorescence are used to irradiate a sample on the spin sample stage for detection; the optical path fixing device is used to adjust and fix the position and angle of the diffraction crystal; The detection method of the railway roadbed filler sulfur content detection device comprises the following steps: Prepare a standard sample containing sulfur and calcium, and measure the standard sample using the detection device to obtain the counting rate intensity of sulfur in the standard sample, Ca:K a Line count rate intensity and Ca:K b Line count rate intensity; According to the counting rate intensity of sulfur element, Ca:K a Line count rate intensity and Ca:K b Line count rate intensity, calculated using the multivariate nonlinear overlapping regression algorithm to obtain the calculated intensity of sulfur in the standard sample; The sulfur calibration curve is established with the percentage of sulfur in the standard sample as the horizontal axis and the calculated intensity of sulfur in the standard sample as the vertical axis. The detection device is used to measure the railway roadbed filler sample to obtain the count rate intensity of sulfur element, Ca:K a Line count rate intensity and Ca:K b Line count rate intensity; According to the counting rate intensity of sulfur element, Ca:K a Line count rate intensity and Ca:K b Line count rate intensity, calculated using the multivariate nonlinear overlapping regression algorithm to obtain the calculated intensity of sulfur in the filler sample; The corrected content of sulfur in the filler sample is obtained by calculation based on the calculated intensity of sulfur in the filler sample and the correction curve.

2. The railway roadbed filler sulfur content detection device according to claim 1 is characterized in that: The diffraction ray is a monochromatic diffraction Rh:L a 2.70keV rays, the characteristic X-ray fluorescence of the element is Ge:K a 9.88keV, Ge:K b 10.98keV element characteristic X-ray fluorescence.

3. The railway roadbed filler sulfur content detection device according to claim 1 or 2, characterized in that: It also includes a crystal adjustment mechanism, which is used to adjust the installation position of the diffraction crystal to meet the Bragg diffraction condition.

4. The railway roadbed filler sulfur content detection device according to claim 1 or 2, characterized in that: It also includes a sample changing component, which is arranged at the bottom of the spin sample stage. The sample changing component moves up and down to drive the spin sample stage to leave the sample measuring position for sample replacement.

5. The device for detecting sulfur content in railway roadbed filler according to claim 1, characterized in that: The spin sample stage comprises a spin component and a sample stage, wherein the spin component is used to connect and drive the sample stage to rotate.

6. The device for detecting sulfur content in railway roadbed filler according to claim 1, characterized in that: The multivariate nonlinear overlapping regression algorithm formula is: S2=((S1+3)×0.803)×(C1+C2), Among them, S2 is the calculated intensity of sulfur, S1 is the count rate intensity of sulfur, and C1 is Ca:K a Line count rate intensity, C2 is Ca:K b Line count rate intensity.

7. The device for detecting sulfur content in railway roadbed filler according to claim 1 or 6, characterized in that: The calibration curve is: S0=(A1× S2)+A0, Where: S0 is the corrected content of sulfur element, S2 is the calculated intensity of sulfur element, A1 is the slope of the calibration curve, and A0 is the intercept of the calibration curve.

8. The device for detecting sulfur content in railway roadbed filler according to claim 1, characterized in that: The standard sample comprises a matrix and sulfur element added into the matrix, wherein the matrix is ​​pure CaCO3 or a mixture of CaCO3 and SiO2.

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