Atmospheric particulate matter analysis method and device based on high and low accelerating voltage coupling analysis

Abstract

A method and device for analyzing atmospheric particulate matter based on high-low accelerating voltage coupled analysis. The method sets three aiming points in the area to be analyzed, performs analysis at low and high accelerating voltages, obtains the first and second aiming point position coordinates of the three aiming points and the first and second particle position coordinates of each particle, obtains the position coordinate difference of the three aiming points, calculates the weight of the position coordinate difference of the aiming points on the particle, calculates the predicted center coordinates of each particle when performing the second analysis, calculates the coordinate range of each particle when performing the second analysis, searches for particles that meet the coordinate range, processes the analysis results of each particle, and obtains the final analysis result of each particle. The present invention can combine the advantages of computer-controlled scanning electron microscope-energy spectrum technology in elemental analysis at high accelerating voltage and imaging at low accelerating voltage to more accurately capture environmental particulate matter on the filter membrane.

Description

Technical Field

[0001] The present invention relates to the technical field of atmospheric particulate matter analysis and detection, and in particular to an atmospheric particulate matter analysis method and device based on high-low accelerating voltage coupled analysis. Background Art

[0002] Atmospheric particulate matter pollution has been one of the most serious environmental problems in my country over the past decade. Scanning electron microscopy combined with energy dispersive spectroscopy (EDS) is a commonly used method for single-particle atmospheric analysis, capable of analyzing the morphology and elemental composition of individual atmospheric particles. The development of computer-controlled scanning electron microscopy-energy dispersive spectroscopy (CCSEM-EDS) technology has enabled automated sample positioning, image acquisition, and compositional analysis, and has been widely used in recent years for characterizing atmospheric particulate matter samples.

[0003] Currently, achieving optimal CCSEM-EDS analysis results requires specific requirements for particulate matter sample collection and electron microscope parameter settings. First, the sampling filter membrane must be smooth and flat. Polycarbonate (PC) filters are currently the most commonly used atmospheric particulate sampling filters for CCSEM-EDS analysis. Second, a higher accelerating voltage (e.g., 20 keV) must be selected. Lower accelerating voltages are insufficient to excite high-atomic-number atoms in the sample to produce X-rays, thus affecting the accuracy and precision of elemental analysis of particulate matter. Furthermore, to achieve a high contrast between the particles and the membrane after imaging, particles are often automatically identified based on the BSE detector signal threshold. However, high accelerating voltages (e.g., 20 keV) have strong penetrating power, making it difficult for CCSEM-EDS to identify particles with a chemical composition similar to that of the filter membrane (e.g., PC), potentially leading to missed identification.

[0004] Therefore, how to invent an atmospheric particulate matter analysis method based on high and low accelerating voltage coupling analysis, which can combine the advantages of scanning electron microscope energy spectrum technology in elemental analysis capability at high accelerating voltage and imaging capability at low accelerating voltage, and more accurately capture environmental particulate matter on the filter membrane, has become an urgent problem to be solved. Summary of the Invention

[0005] To this end, the present invention provides a method and apparatus for analyzing atmospheric particulate matter based on coupled analysis using high and low accelerating voltages. This method combines the advantages of scanning electron microscopy (SEM) energy-dispersive spectroscopy (EDS), which offers elemental analysis capabilities at high accelerating voltages and imaging capabilities at low accelerating voltages, to more accurately capture ambient particulate matter on filter membranes.

[0006] To achieve the above objectives, the present invention provides the following technical solution: an atmospheric particulate matter analysis method based on high-low accelerating voltage coupled analysis, comprising:

[0007] The environmental particulate matter sample is placed in a scanning electron microscope sample chamber, and three aiming points are set in the area to be analyzed; the environmental particulate matter sample is first analyzed by the scanning electron microscope at a low accelerating voltage, and the first aiming point position coordinates of the three aiming points, the first particle position coordinates of each particle, and the maximum particle size data are recorded and obtained;

[0008] Performing a second analysis on the environmental particulate matter sample using the scanning electron microscope at a high acceleration voltage, recording and obtaining the second aiming point position coordinates of the three aiming points and the second particle position coordinates of each particle;

[0009] Obtaining a position coordinate difference between the first aiming point position coordinate and the second aiming point position coordinate of the three aiming points by calculation;

[0010] Obtaining, by calculation, a distance from each particle to each of the three aiming points based on the first particle position coordinates of each particle; and obtaining, by calculation, a weight of the position coordinate difference of each of the three aiming points for each particle based on the distance from each particle to each of the three aiming points;

[0011] Obtaining the predicted center coordinates of each particle during the second analysis by calculating the weight of each particle based on the difference between the first particle position coordinates and the position coordinates of each of the three aiming points using an inverse distance weighting strategy;

[0012] Based on the maximum particle size data of each particle and the predicted center coordinates of each particle when performing the second analysis, the coordinate range of each particle when performing the second analysis is calculated; based on the coordinate range of each particle when performing the second analysis, particles that meet the coordinate range are searched in the second analysis results; based on the search results, the analysis results of each particle are processed to obtain the final analysis results of each particle in the environmental particulate matter.

[0013] As a preferred embodiment of the atmospheric particulate matter analysis method based on high-low acceleration voltage coupling analysis, in the process of calculating the distance from each particle to each of the three aiming points based on the first particle position coordinates of each particle, the calculation formula for the distance from each particle to each of the three aiming points is:

[0014]

[0015] Where, d i,j is the distance from the i-th particle to the j-th aiming point obtained from the first analysis; x i and y i is the position coordinate of the i-th particle obtained from the first analysis; 1,j and y1,j is the coordinate position of the j-th aiming point obtained from the first analysis.

[0016] As a preferred solution of the atmospheric particulate matter analysis method based on high and low acceleration voltage coupling analysis, in the process of calculating the weight of each particle by the position coordinate difference of each of the three aiming points based on the distance from each particle to each of the three aiming points, the calculation formula for the weight of each particle by the position coordinate difference of each aiming point is:

[0017]

[0018] Where w i,j The weight of the coordinate difference calculated for the j-th aiming point on the i-th particle.

[0019] As a preferred solution of the atmospheric particulate matter analysis method based on high and low acceleration voltage coupling analysis, in the process of calculating the predicted center coordinates of each particle during the second analysis using the inverse distance weighted strategy, the calculation formula for the predicted center coordinates of each particle during the second analysis is:

[0020]

[0021] Where x i ′ and y i ′ are the predicted center coordinates of the particle in the second analysis; Δx j and Δy j are position coordinate differences between the first aiming point position coordinates and the second aiming point position coordinates of the three aiming points.

[0022] As a preferred solution of the atmospheric particulate matter analysis method based on high and low acceleration voltage coupling analysis, in the process of calculating and obtaining the coordinate range of each particle during the second analysis based on the maximum particle size data of each particle, the coordinate range expression is:

[0023] x i ′-D i ≤x≤x i ′+D i

[0024] y i ′-D i ≤y≤y i ′+D i

[0025] Where D i is the maximum particle size of the i-th particle obtained in the first analysis.

[0026] The present invention also provides an atmospheric particulate matter analysis device based on high-low accelerating voltage coupled analysis, which uses the above-mentioned atmospheric particulate matter analysis method based on high-low accelerating voltage coupled analysis, including:

[0027] A low accelerating voltage analysis module is configured to place an environmental particulate matter sample into a scanning electron microscope sample chamber and set three aiming points in the area to be analyzed; perform a first analysis of the environmental particulate matter sample using the scanning electron microscope at a low accelerating voltage, and record and obtain the first aiming point position coordinates of the three aiming points, the first particle position coordinates of each particle, and the maximum particle size data;

[0028] a high accelerating voltage analysis module, configured to perform a second analysis of the environmental particulate matter sample using the scanning electron microscope under a high accelerating voltage, and record and obtain the second aiming point position coordinates of the three aiming points and the second particle position coordinates of each particle;

[0029] an aiming point position coordinate difference calculation and acquisition module, configured to obtain, by calculation, a position coordinate difference between the first aiming point position coordinate and the second aiming point position coordinate of the three aiming points;

[0030] an aiming point position coordinate difference weight calculation and acquisition module, configured to calculate, based on the first particle position coordinate of each particle, a distance from each particle to each of the three aiming points; and calculate, based on the distance from each particle to each of the three aiming points, a weight of the position coordinate difference of each of the three aiming points for each particle;

[0031] a particle predicted center coordinate calculation and acquisition module, configured to calculate and acquire the predicted center coordinates of each particle during the second analysis using an inverse distance weighted strategy based on a weight assigned to each particle by a difference between the first particle position coordinates of each particle and the position coordinates of each of the three aiming points;

[0032] The particle final analysis result acquisition module is used to calculate the coordinate range of each particle when performing the second analysis based on the maximum particle size data of each particle and the predicted center coordinates of each particle when performing the second analysis; based on the coordinate range of each particle when performing the second analysis, search for particles that meet the coordinate range in the second analysis results; and based on the search results, process the analysis results of each particle to obtain the final analysis result of each particle in the environmental particulate matter.

[0033] As a preferred solution of the atmospheric particulate matter analysis device based on high-low acceleration voltage coupling analysis, in the aiming point position coordinate difference weight calculation and acquisition module, in the process of calculating and acquiring the distance from each particle to each of the three aiming points based on the first particle position coordinates of each particle, the calculation formula for the distance from each particle to each of the three aiming points is:

[0034]

[0035] Where, d i,j is the distance from the i-th particle to the j-th aiming point obtained from the first analysis; x i and y i is the position coordinate of the i-th particle obtained from the first analysis; 1,j and y 1,j is the coordinate position of the j-th aiming point obtained from the first analysis.

[0036] As a preferred solution of the atmospheric particulate matter analysis device based on high-low acceleration voltage coupling analysis, in the aiming point position coordinate difference weight calculation and acquisition module, in the process of calculating and acquiring the weight of the position coordinate difference of each of the three aiming points for each particle based on the distance from each particle to each of the three aiming points, the calculation formula of the weight of the position coordinate difference of each aiming point for each particle is:

[0037]

[0038] Where w i,j The weight of the coordinate difference calculated for the j-th aiming point on the i-th particle.

[0039] As a preferred solution of the atmospheric particulate matter analysis device based on high and low acceleration voltage coupling analysis, in the particle predicted center coordinate calculation and acquisition module, in the process of calculating and acquiring the predicted center coordinates of each particle during the second analysis using the inverse distance weighted strategy, the calculation formula for the predicted center coordinates of each particle during the second analysis is:

[0040]

[0041] Where x i ′ and y i ′ are the predicted center coordinates of the particle in the second analysis; Δx j and Δy j are position coordinate differences between the first aiming point position coordinates and the second aiming point position coordinates of the three aiming points.

[0042] As a preferred solution of the atmospheric particulate matter analysis device based on high and low acceleration voltage coupled analysis, in the particle final analysis result acquisition module, in the process of calculating and obtaining the coordinate range of each particle during the second analysis based on the maximum particle size data of each particle, the coordinate range expression is:

[0043] x i ′-D i ≤x≤x i ′+D i

[0044] y i ′-D i ≤y≤y i ′+D i

[0045] Where D i is the maximum particle size of the i-th particle obtained in the first analysis.

[0046] The present invention has the following advantages: an environmental particulate matter sample is placed in a scanning electron microscope sample chamber, and three aiming points are set in the area to be analyzed; the environmental particulate matter sample is analyzed for the first time by the scanning electron microscope at a low acceleration voltage, and the first aiming point position coordinates of the three aiming points, the first particle position coordinates of each particle and the maximum particle size data are recorded and obtained; the environmental particulate matter sample is analyzed for the second time by the scanning electron microscope at a high acceleration voltage, and the second aiming point position coordinates of the three aiming points and the second particle position coordinates of each particle are recorded and obtained; the position coordinate difference between the first aiming point position coordinates and the second aiming point position coordinates of the three aiming points is obtained by calculation; the distance of each particle to each of the three aiming points is obtained by calculation according to the first particle position coordinates of each particle; the maximum particle size data of each particle to the three aiming points is obtained according to the maximum particle size data of each particle to the three aiming points The method comprises the following steps: calculating the distance between each aiming point in the three aiming points, obtaining the weight of each particle for the position coordinate difference of each aiming point in the three aiming points; calculating the predicted center coordinate of each particle during the second analysis based on the first particle position coordinate of each particle and the weight of each particle for the position coordinate difference of each aiming point in the three aiming points; calculating the coordinate range of each particle during the second analysis based on the maximum particle size data of each particle and the predicted center coordinate of each particle during the second analysis; searching the second analysis results for particles that meet the coordinate range based on the coordinate range of each particle during the second analysis; processing the analysis results of each particle based on the search results to obtain the final analysis result of each particle in the environmental particulate matter. The present invention addresses the problem that conventional computer-controlled scanning electron microscope (CEM) energy spectrum technology has low efficiency in identifying particles with similar chemical composition to membrane composition when analyzing environmental particulate matter samples. The present invention combines the advantages of CEM-EDSEM technology in elemental analysis at high accelerating voltage and imaging at low accelerating voltage to more accurately capture environmental particulate matter on the filter membrane. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] To more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for the embodiments or the description of the prior art. Obviously, the drawings described below are merely exemplary, and those skilled in the art can, without inventive effort, derive other implementation drawings based on the provided drawings.

[0048] The structures, proportions, sizes, etc. illustrated in this specification are intended solely to complement the contents disclosed herein and to facilitate understanding and reading by persons skilled in the art. They are not intended to limit the conditions under which the present invention may be implemented and therefore have no substantive technical significance. Any structural modifications, changes in proportions, or adjustments in sizes, without affecting the efficacy and objectives of the present invention, shall remain within the scope of the technical contents disclosed herein.

[0049] Figure 1 A schematic flow chart of an atmospheric particulate matter analysis method based on high-low accelerating voltage coupled analysis provided in Example 1 of the present invention;

[0050] Figure 2 Schematic diagram of specific implementation steps of the atmospheric particulate matter analysis method based on high-low accelerating voltage coupled analysis provided in Example 1 of the present invention;

[0051] Figure 3 Schematic diagram of the particulate matter sample analysis area and aiming point settings in the atmospheric particulate matter analysis method based on high and low accelerating voltage coupled analysis provided in Example 1 of the present invention;

[0052] Figure 4 Schematic diagram of the imaging effect of carbonaceous particles analyzed by a scanning electron microscope under low accelerating voltage (5 keV) and high accelerating voltage (20 keV) conditions in the atmospheric particulate matter analysis method based on high-low accelerating voltage coupled analysis provided in Example 1 of the present invention;

[0053] Figure 5 Schematic diagram comparing the proportion of carbonaceous particles (C-rich) in the second analysis (high accelerating voltage) results and the proportion in the high- and low-accelerating voltage coupled analysis results in the atmospheric particulate matter analysis method based on high- and low-accelerating voltage coupled analysis provided in Example 1 of the present invention;

[0054] Figure 6 Schematic diagram of the architecture of an atmospheric particulate matter analysis device based on high-low accelerating voltage coupled analysis provided in Example 2 of the present invention. DETAILED DESCRIPTION

[0055] The following describes the implementation of the present invention using specific embodiments. Those skilled in the art will readily understand the other advantages and benefits of the present invention from the disclosure herein. Obviously, the embodiments described are only a portion of the present invention, not all of it. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are intended to fall within the scope of protection of the present invention.

[0056] Example 1

[0057] See also Figure 1 and Figure 2 Embodiment 1 of the present invention provides an atmospheric particulate matter analysis method based on high-low accelerating voltage coupled analysis, comprising:

[0058] S1. Place an environmental particulate matter sample into a scanning electron microscope sample chamber and set three aiming points in the area to be analyzed; perform a first analysis of the environmental particulate matter sample using the scanning electron microscope at a low accelerating voltage, and record and obtain the first aiming point position coordinates of the three aiming points, the first particle position coordinates of each particle, and the maximum particle size data;

[0059] S2. performing a second analysis on the environmental particulate matter sample using the scanning electron microscope at a high acceleration voltage, recording and obtaining the second aiming point position coordinates of the three aiming points and the second particle position coordinates of each particle;

[0060] S3. Obtaining a position coordinate difference between the first aiming point position coordinate and the second aiming point position coordinate of the three aiming points by calculation;

[0061] S4. Obtaining, by calculation, the distance from each particle to each of the three aiming points based on the first particle position coordinates of each particle; and obtaining, by calculation, the weight of the position coordinate difference of each of the three aiming points for each particle based on the distance from each particle to each of the three aiming points;

[0062] S5. Calculate the predicted center coordinates of each particle during the second analysis using an inverse distance weighted strategy based on a weight assigned to each particle by a difference between the first particle position coordinates and the position coordinates of each of the three aiming points.

[0063] S6. Calculate and obtain the coordinate range of each particle during the second analysis based on the maximum particle size data of each particle and the predicted center coordinates of each particle during the second analysis; search the second analysis results for particles that meet the coordinate range based on the coordinate range of each particle during the second analysis; and process the analysis results of each particle based on the search results to obtain a final analysis result for each particle in the environmental particulate matter.

[0064] In this embodiment, in step S1, an environmental particulate matter sample is placed in a scanning electron microscope sample chamber, and three aiming points are set in the area to be analyzed; the environmental particulate matter sample is first analyzed by the scanning electron microscope at a low acceleration voltage, and the first aiming point position coordinates of the three aiming points, the first particle position coordinates of each particle, and the maximum particle size data are recorded and obtained;

[0065] Specifically, the environmental particulate matter sample is placed in the scanning electron microscope sample chamber, and the sample is first analyzed at a low acceleration voltage (5kev). During the analysis, the sample stage is prohibited from rotating and tilting. The environmental particulate matter samples in this embodiment are 4 environmental particulate matter samples collected in Beijing using a polycarbonate filter membrane. Carbonaceous particles (C-rich) have similar chemical compositions to polycarbonate filter membranes, both consisting of C and O elements. Therefore, taking the analysis effect of carbonaceous particles as an example, three aiming points should be set in the area to be analyzed during sample analysis, such as Figure 3 And record the coordinates of the first aiming point of the three aiming points (x 1,j ,y 1,j ), where j represents the jth aiming point. The first particle position coordinates and maximum particle size data of each particle are recorded simultaneously.

[0066] In this embodiment, in step S2, the environmental particulate matter sample is analyzed a second time by the scanning electron microscope under a high acceleration voltage, and the second aiming point position coordinates of the three aiming points and the second particle position coordinates of each particle are recorded and obtained;

[0067] Specifically, the second analysis of the atmospheric particulate matter sample was performed under high acceleration voltage (20kev) conditions, and the analysis area remained the same as the first step. The position coordinates of the second aiming point of the three aiming points (x 2,j ,y 2,j ), where j represents the jth aiming point. At the same time, the second particle position coordinates of each particle analyzed are recorded. The imaging effect of carbonaceous particles under 5kev and 20kev conditions is as follows Figure 4 shown.

[0068] In this embodiment, in step S3, the position coordinate difference between the first aiming point position coordinate and the second aiming point position coordinate of the three aiming points is obtained by calculation;

[0069] Specifically, the coordinate difference (Δx j ,Δy j ), where Δx j =x 2,j -x 1,j , Δy j =x 2,j -x 1,j .

[0070] In this embodiment, in step S4, the distance from each particle to each of the three aiming points is obtained by calculation based on the first particle position coordinates of each particle;

[0071] Specifically, the calculation formula for the distance from each particle to each of the three aiming points is:

[0072]

[0073] Where, d i,j is the distance from the i-th particle to the j-th aiming point obtained from the first analysis; x i and y i is the position coordinate of the i-th particle obtained from the first analysis; 1,j and y 1,j is the coordinate position of the j-th aiming point obtained from the first analysis.

[0074] Calculate, based on the distance from each particle to each of the three aiming points, a weight of the position coordinate difference of each of the three aiming points on each particle;

[0075] Specifically, the calculation formula for the weight of each particle based on the position coordinate difference of each aiming point is:

[0076]

[0077] Where w i,j The weight of the coordinate difference calculated for the j-th aiming point on the i-th particle.

[0078] In this embodiment, in step S5, the predicted center coordinates of each particle during the second analysis are calculated using an inverse distance weighted strategy based on the weight of each particle obtained by calculating the difference between the first particle position coordinates of each particle and the position coordinates of each of the three aiming points.

[0079] Specifically, the calculation formula for the predicted center coordinates of each particle during the second analysis is:

[0080]

[0081] Where x i ′ and y i ′ are the predicted center coordinates of the particle in the second analysis; Δx j and Δy j are position coordinate differences between the first aiming point position coordinates and the second aiming point position coordinates of the three aiming points.

[0082] In this embodiment, in step S6, the coordinate range of each particle when performing the second analysis is calculated based on the maximum particle size data of each particle and the predicted center coordinates of each particle when performing the second analysis;

[0083] Specifically, the coordinate range expression is:

[0084] x i ′-D i≤x≤x i ′+D i

[0085] y i ′-D i ≤y≤y i ′+D i

[0086] Where D i is the maximum particle size of the i-th particle obtained in the first analysis.

[0087] According to the coordinate range of each particle during the second analysis, particles that meet the coordinate range are searched in the second analysis results; according to the search results, the analysis results of each particle are processed to obtain the final analysis results of each particle in the environmental particulate matter.

[0088] Specifically, based on the above coordinate range, the second analysis results are searched for particles that fit within this coordinate range. If a corresponding particle can be retrieved, it indicates that the particle was detected in both analyses, and the final analysis result is based on the second analysis result. Conversely, if no particle is retrieved, the particle is marked as "unmatched" and its single particle image, particle size, and chemical composition data are recorded. The second analysis results are combined with the particles marked as "unmatched" in the first analysis results to obtain the final atmospheric particulate matter analysis results that combine both high and low accelerating voltage analysis modes.

[0089] In this embodiment, considering the high uncertainty of high atomic number elements under low accelerating voltage conditions, the present invention divides the particles analyzed in the first analysis into two categories: carbonaceous particles (C-rich) and others (Other). The second analysis (under high accelerating voltage) divides the particles into different types according to the main elements of the particles. Based on the present invention, the analysis capability of carbonaceous particles can be significantly improved. Compared with the analysis under high accelerating voltage alone, the computer-controlled scanning electron microscope energy spectrum technology can be used to analyze PM1 and PM2.5 particles. 2.5-1 The detection ability of carbonaceous particles in the particle size segment was improved by 39.8% and 88.4% on average. Figure 5 shown.

[0090] In summary, the present invention places an environmental particulate matter sample into a scanning electron microscope sample chamber, and sets three aiming points in the area to be analyzed; performs a first analysis on the environmental particulate matter sample by the scanning electron microscope at a low acceleration voltage, records and obtains the first aiming point position coordinates of the three aiming points, the first particle position coordinates of each particle, and the maximum particle size data; performs a second analysis on the environmental particulate matter sample by the scanning electron microscope at a high acceleration voltage, records and obtains the second aiming point position coordinates of the three aiming points and the second particle position coordinates of each particle; obtains the position coordinate difference between the first aiming point position coordinates and the second aiming point position coordinates of the three aiming points by calculation; obtains the distance from each particle to each of the three aiming points by calculation based on the first particle position coordinates of each particle; obtains the maximum particle size data based on the distance from each particle to the three aiming points The method comprises the following steps: calculating the distance between each aiming point and the weight of each particle for the position coordinate difference of each of the three aiming points; calculating the predicted center coordinate of each particle during the second analysis based on the first particle position coordinate of each particle and the weight of the position coordinate difference of each of the three aiming points for each particle using an inverse distance weighting strategy; calculating the coordinate range of each particle during the second analysis based on the maximum particle size data of each particle and the predicted center coordinate of each particle during the second analysis; searching the second analysis results for particles that meet the coordinate range based on the coordinate range of each particle during the second analysis; processing the analysis results of each particle based on the search results to obtain the final analysis result of each particle in the environmental particulate matter. The present invention addresses the problem that conventional computer-controlled scanning electron microscope energy spectrum technology has low efficiency in identifying particles with chemical compositions similar to those of membranes when analyzing environmental particulate matter samples. The present invention combines the advantages of computer-controlled scanning electron microscope-energy spectrum technology in elemental analysis capabilities at high accelerating voltages and imaging capabilities at low accelerating voltages to more accurately capture environmental particulate matter on the filter membrane.

[0091] It should be noted that the method of the embodiments of the present disclosure can be performed by a single device, such as a computer or server. The method of the embodiments of the present disclosure can also be applied in a distributed scenario, where multiple devices cooperate to perform the method. In such a distributed scenario, one of the multiple devices may only perform one or more steps of the method of the embodiments of the present disclosure, and the multiple devices will interact with each other to complete the method.

[0092] It should be noted that the above description is limited to some embodiments of the present disclosure. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in an order different from that described in the above embodiments and still achieve the desired results. Furthermore, the processes depicted in the accompanying drawings do not necessarily require the specific order or sequential order shown to achieve the desired results. In certain embodiments, multitasking and parallel processing are also possible or may be advantageous.

[0093] Example 2

[0094] See also Figure 6 Embodiment 2 of the present invention provides an atmospheric particulate matter analysis device based on high-low accelerating voltage coupled analysis, comprising:

[0095] The low accelerating voltage analysis module 001 is used to place an environmental particulate matter sample into a scanning electron microscope sample chamber and set three aiming points in the area to be analyzed; perform a first analysis of the environmental particulate matter sample using the scanning electron microscope at a low accelerating voltage, and record and obtain the first aiming point position coordinates of the three aiming points, the first particle position coordinates of each particle, and the maximum particle size data;

[0096] a high acceleration voltage analysis module 002 for performing a second analysis of the environmental particulate matter sample using the scanning electron microscope under a high acceleration voltage, recording and obtaining the second aiming point position coordinates of the three aiming points and the second particle position coordinates of each particle;

[0097] An aiming point position coordinate difference calculation and acquisition module 003 is configured to obtain, by calculation, a position coordinate difference between the first aiming point position coordinate and the second aiming point position coordinate of the three aiming points;

[0098] an aiming point position coordinate difference weight calculation and acquisition module 004, configured to calculate, based on the first particle position coordinate of each particle, a distance from each particle to each of the three aiming points; and calculate, based on the distance from each particle to each of the three aiming points, a weight of the position coordinate difference of each of the three aiming points for each particle;

[0099] a particle predicted center coordinate calculation and acquisition module 005, configured to calculate the predicted center coordinates of each particle during the second analysis using an inverse distance weighted strategy based on a weight assigned to each particle by a difference between the first particle position coordinates of each particle and the position coordinates of each of the three aiming points;

[0100] The particle final analysis result acquisition module 006 is used to calculate the coordinate range of each particle during the second analysis based on the maximum particle size data of each particle and the predicted center coordinates of each particle during the second analysis; based on the coordinate range of each particle during the second analysis, search for particles that meet the coordinate range in the second analysis results; and based on the search results, process the analysis results of each particle to obtain the final analysis result of each particle in the environmental particulate matter.

[0101] In this embodiment, in the aiming point position coordinate difference weight calculation and acquisition module 004, in the process of calculating and acquiring the distance from each particle to each of the three aiming points based on the first particle position coordinate of each particle, the calculation formula for the distance from each particle to each of the three aiming points is:

[0102]

[0103] Where, d i,j is the distance from the i-th particle to the j-th aiming point obtained from the first analysis; x i and y i is the position coordinate of the i-th particle obtained from the first analysis; 1,j and y 1,j is the coordinate position of the j-th aiming point obtained from the first analysis.

[0104] In this embodiment, in the aiming point position coordinate difference weight calculation and acquisition module 004, in the process of calculating and acquiring the weight of the position coordinate difference of each of the three aiming points for each particle based on the distance from each particle to each of the three aiming points, the calculation formula for the weight of the position coordinate difference of each aiming point for each particle is:

[0105]

[0106] Where w i,j The weight of the coordinate difference calculated for the j-th aiming point on the i-th particle.

[0107] In this embodiment, in the particle predicted center coordinate calculation and acquisition module 005, in the process of calculating and acquiring the predicted center coordinates of each particle during the second analysis using the inverse distance weighted strategy, the calculation formula for the predicted center coordinates of each particle during the second analysis is:

[0108]

[0109] Where x i ′ and y i′ are the predicted center coordinates of the particle in the second analysis; Δx j and Δy j are position coordinate differences between the first aiming point position coordinates and the second aiming point position coordinates of the three aiming points.

[0110] In this embodiment, in the particle final analysis result acquisition module 006, in the process of calculating and acquiring the coordinate range of each particle during the second analysis based on the maximum particle size data of each particle, the coordinate range expression is:

[0111] x i ′-D i ≤x≤x i ′+D i

[0112] y i ′-D i ≤y≤y i ′+D i

[0113] Where D i is the maximum particle size of the i-th particle obtained in the first analysis.

[0114] It should be noted that the information interaction, execution process, etc. between the modules / units of the above-mentioned system are based on the same concept as the method embodiment in Example 1 of the present application, and the technical effects they bring are the same as those of the method embodiment of the present application. For specific contents, please refer to the description in the method embodiment shown above in the present application, and no further details will be given here.

[0115] Example 3

[0116] Embodiment 3 of the present invention provides a non-transitory computer-readable storage medium, in which the program code of an atmospheric particulate matter analysis method based on high-low acceleration voltage coupling analysis is stored. The program code includes instructions for executing the atmospheric particulate matter analysis method based on high-low acceleration voltage coupling analysis of embodiment 1 or any possible implementation thereof.

[0117] Computer-readable storage media can be any available medium that can be accessed by a computer or a data storage device such as a server or data center that includes one or more available media. The available media can be magnetic media (e.g., floppy disks, hard disks, magnetic tapes), optical media (e.g., DVDs), or semiconductor media (e.g., solid-state drives (SSDs)).

[0118] Example 4

[0119] Embodiment 4 of the present invention provides an electronic device, including: a memory and a processor;

[0120] The processor and the memory communicate with each other through a bus; the memory stores program instructions that can be executed by the processor, and the processor calls the program instructions to execute the atmospheric particulate matter analysis method based on high and low acceleration voltage coupling analysis of Example 1 or any possible implementation thereof.

[0121] Specifically, the processor can be implemented by hardware or by software. When implemented by hardware, the processor can be a logic circuit, an integrated circuit, etc.; when implemented by software, the processor can be a general-purpose processor, which is implemented by reading software code stored in a memory. The memory can be integrated into the processor or located outside the processor and exist independently.

[0122] In the above embodiments, it can be implemented in whole or in part by software, hardware, firmware or any combination thereof. When implemented using software, it can be implemented in whole or in part in the form of a computer program product. The computer program product includes one or more computer instructions. When the computer program instructions are loaded and executed on a computer, the process or function described in the embodiment of the present invention is generated in whole or in part. The computer can be a general-purpose computer, a special-purpose computer, a computer network, or other programmable devices. The computer instructions can be stored in a computer-readable storage medium, or transmitted from one computer-readable storage medium to another computer-readable storage medium. For example, the computer instructions can be transmitted from a website, computer, server or data center to another website, computer, server or data center via a wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode.

[0123] Obviously, those skilled in the art will appreciate that the various modules or steps of the present invention described above can be implemented using a general-purpose computing device, centralized on a single computing device, or distributed across a network of multiple computing devices. Alternatively, they can be implemented using program code executable by a computing device, which can then be stored in a storage device and executed by the computing device. In some cases, the steps shown or described can be performed in a different order than that shown, or can be fabricated as separate integrated circuit modules, or multiple modules or steps can be fabricated as a single integrated circuit module. Thus, the present invention is not limited to any particular combination of hardware and software.

[0124] Although the present invention has been described in detail above using general descriptions and specific embodiments, it will be apparent to those skilled in the art that modifications and improvements may be made thereto. Therefore, such modifications and improvements, without departing from the spirit of the present invention, are intended to be within the scope of protection claimed herein.

Claims

1. An atmospheric particulate matter analysis method based on high and low accelerating voltage coupling analysis, characterized in that: include: The environmental particulate matter sample is placed in a scanning electron microscope sample chamber, and three aiming points are set in the area to be analyzed; the environmental particulate matter sample is first analyzed by the scanning electron microscope at a low accelerating voltage, and the first aiming point position coordinates of the three aiming points, the first particle position coordinates of each particle, and the maximum particle size data are recorded and obtained; Performing a second analysis on the environmental particulate matter sample using the scanning electron microscope at a high acceleration voltage, recording and obtaining the second aiming point position coordinates of the three aiming points and the second particle position coordinates of each particle; Obtaining a position coordinate difference between the first aiming point position coordinate and the second aiming point position coordinate of the three aiming points by calculation; Obtaining, by calculation, a distance from each particle to each of the three aiming points based on the first particle position coordinates of each particle; and obtaining, by calculation, a weight of the position coordinate difference of each of the three aiming points for each particle based on the distance from each particle to each of the three aiming points; Obtaining the predicted center coordinates of each particle during the second analysis by calculating the weight of each particle based on the difference between the first particle position coordinates and the position coordinates of each of the three aiming points using an inverse distance weighting strategy; Based on the maximum particle size data of each particle and the predicted center coordinates of each particle when performing the second analysis, the coordinate range of each particle when performing the second analysis is calculated; based on the coordinate range of each particle when performing the second analysis, particles that meet the coordinate range are searched in the second analysis results; based on the search results, the analysis results of each particle are processed to obtain the final analysis results of each particle in the environmental particulate matter.

2. The atmospheric particulate matter analysis method based on high and low accelerating voltage coupled analysis according to claim 1, characterized in that: In the process of obtaining the distance from each particle to each of the three aiming points by calculation based on the first particle position coordinates of each particle, the calculation formula for the distance from each particle to each of the three aiming points is: Where, d i,j is the distance from the i-th particle to the j-th aiming point obtained from the first analysis; x i and y i is the position coordinate of the i-th particle obtained from the first analysis; 1,j and y 1,j is the coordinate position of the j-th aiming point obtained from the first analysis.

3. The atmospheric particulate matter analysis method based on high and low accelerating voltage coupled analysis according to claim 2, characterized in that: In the process of calculating the weight of each particle based on the position coordinate difference of each of the three aiming points according to the distance from each particle to each of the three aiming points, the weight of each particle based on the position coordinate difference of each aiming point is calculated as follows: Where w i,j The weight of the coordinate difference calculated for the j-th aiming point on the i-th particle.

4. The atmospheric particulate matter analysis method based on high and low accelerating voltage coupled analysis according to claim 3, characterized in that: In the process of calculating and obtaining the predicted center coordinates of each particle during the second analysis by the inverse distance weighted strategy, the calculation formula for the predicted center coordinates of each particle during the second analysis is: Where x i ′ and y i ′ are the predicted center coordinates of the particle in the second analysis; Δx j and Δy j are position coordinate differences between the first aiming point position coordinates and the second aiming point position coordinates of the three aiming points.

5. The atmospheric particulate matter analysis method based on high and low accelerating voltage coupled analysis according to claim 4, characterized in that: In the process of calculating and obtaining the coordinate range of each particle during the second analysis based on the maximum particle size data of each particle, the coordinate range expression is: x i ′-D i ≤x≤x i ′+D i y i ′-D i ≤y≤y i ′+D i Where D i is the maximum particle size of the i-th particle obtained in the first analysis.

6. An atmospheric particulate matter analysis device based on high-low accelerating voltage coupling analysis, using the atmospheric particulate matter analysis method based on high-low accelerating voltage coupling analysis according to any one of claims 1 to 5, characterized in that: include: A low accelerating voltage analysis module is configured to place an environmental particulate matter sample into a scanning electron microscope sample chamber and set three aiming points in the area to be analyzed; perform a first analysis of the environmental particulate matter sample using the scanning electron microscope at a low accelerating voltage, and record and obtain the first aiming point position coordinates of the three aiming points, the first particle position coordinates of each particle, and the maximum particle size data; a high accelerating voltage analysis module, configured to perform a second analysis of the environmental particulate matter sample using the scanning electron microscope under a high accelerating voltage, and record and obtain the second aiming point position coordinates of the three aiming points and the second particle position coordinates of each particle; an aiming point position coordinate difference calculation and acquisition module, configured to obtain, by calculation, a position coordinate difference between the first aiming point position coordinate and the second aiming point position coordinate of the three aiming points; an aiming point position coordinate difference weight calculation and acquisition module, configured to calculate, based on the first particle position coordinate of each particle, a distance from each particle to each of the three aiming points; and calculate, based on the distance from each particle to each of the three aiming points, a weight of the position coordinate difference of each of the three aiming points for each particle; a particle predicted center coordinate calculation and acquisition module, configured to calculate and acquire the predicted center coordinates of each particle during the second analysis using an inverse distance weighted strategy based on a weight assigned to each particle by a difference between the first particle position coordinates of each particle and the position coordinates of each of the three aiming points; The particle final analysis result acquisition module is used to calculate the coordinate range of each particle when performing the second analysis based on the maximum particle size data of each particle and the predicted center coordinates of each particle when performing the second analysis; based on the coordinate range of each particle when performing the second analysis, search for particles that meet the coordinate range in the second analysis results; and based on the search results, process the analysis results of each particle to obtain the final analysis result of each particle in the environmental particulate matter.

7. The atmospheric particulate matter analysis device based on high and low accelerating voltage coupled analysis according to claim 6, characterized in that: In the aiming point position coordinate difference weighted calculation and acquisition module, in the process of calculating and acquiring the distance from each particle to each of the three aiming points based on the first particle position coordinate of each particle, the calculation formula for the distance from each particle to each of the three aiming points is: Where, d i,j is the distance from the i-th particle to the j-th aiming point obtained from the first analysis; x i and y i is the position coordinate of the i-th particle obtained from the first analysis; 1,j and y 1,j is the coordinate position of the j-th aiming point obtained from the first analysis.

8. The atmospheric particulate matter analysis device based on high and low accelerating voltage coupled analysis according to claim 7, characterized in that: In the aiming point position coordinate difference weight calculation and acquisition module, in the process of calculating and acquiring the weight of the position coordinate difference of each of the three aiming points for each particle based on the distance from each particle to each of the three aiming points, the calculation formula for the weight of the position coordinate difference of each aiming point for each particle is: Where w i,j The weight of the coordinate difference calculated for the j-th aiming point on the i-th particle.

9. The atmospheric particulate matter analysis device based on high and low accelerating voltage coupled analysis according to claim 8, characterized in that: In the particle predicted center coordinate calculation and acquisition module, in the process of calculating and acquiring the predicted center coordinates of each particle during the second analysis using the inverse distance weighted strategy, the calculation formula for the predicted center coordinates of each particle during the second analysis is: Where x i ′ and y i ′ are the predicted center coordinates of the particle in the second analysis; Δx j and Δy j are position coordinate differences between the first aiming point position coordinates and the second aiming point position coordinates of the three aiming points.

10. The atmospheric particulate matter analysis device based on high and low accelerating voltage coupled analysis according to claim 9, characterized in that: In the particle final analysis result acquisition module, in the process of calculating and acquiring the coordinate range of each particle during the second analysis based on the maximum particle size data of each particle, the coordinate range expression is: x i ′-D i ≤x≤x i ′+D i y i ′-D i ≤y≤y i ′+D i Where D i is the maximum particle size of the i-th particle obtained in the first analysis.

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