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

Abstract

The invention discloses an atmospheric particulate analysis method and device based on high and low acceleration voltage coupling analysis, and the method comprises the steps: setting three aiming points in a to-be-analyzed region, carrying out the analysis under low acceleration voltage and high acceleration voltage, and obtaining the position coordinates of a first aiming point and a second aiming point of the three aiming points and the position coordinates of a first particle and a second particle of each particle respectively; obtaining the position coordinate difference of the three aiming points; calculating and obtaining the weight of the position coordinate difference of the aiming point on the particles; calculating to obtain a predicted center coordinate of each particle during second analysis; calculating to obtain a coordinate range of each particle during secondary analysis; and searching the particles satisfying the coordinate range, and processing the analysis result of each particle to obtain the final analysis result of each particle. According to the invention, the environmental particulate matters on the filter membrane can be captured more accurately by combining the advantages of the computer-controlled scanning electron microscope-energy spectrum technology of element analysis capability under high acceleration voltage and imaging capability under low acceleration voltage.

Description

Technical Field

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

[0002] Atmospheric particulate pollution is one of the most serious environmental problems in my country in the past decade. Scanning electron microscopy combined with energy spectrum analysis is a commonly used atmospheric single particle analysis method, which can analyze and obtain the morphology and elemental composition of individual atmospheric particles. The development of computer-controlled scanning electron microscopy-energy spectrum (CCSEM-EDS) technology has realized automatic sample positioning, image acquisition and composition analysis, and has been widely used in the characterization of atmospheric particulate samples in recent years.

[0003] At present, in order to obtain better analysis results for CCSEM-EDS, there are special requirements for particulate matter sample collection and electron microscope parameter settings. First, the sampling filter membrane needs to be smooth and flat. Polycarbonate (PC) filter membrane is currently the most commonly used atmospheric particulate matter sampling filter membrane for CCSEM-EDS analysis; second, a higher acceleration voltage (such as 20keV) is selected. A lower acceleration voltage is not enough to excite high atomic number atoms in the sample to produce X-rays, thus affecting the accuracy and precision of the elemental analysis of particulate matter; in addition, in order to make the particles and the membrane have a higher contrast after imaging, the particles are often automatically identified based on the BSE detector signal threshold. However, high acceleration voltages (such as 20keV) have strong penetration ability, and it is difficult for CCSEM-EDS to identify particles (such as carbonaceous particles) with similar chemical composition to the filter membrane (such as PC), and there is a possibility of 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 an atmospheric particulate matter analysis method and device based on high and low accelerating voltage coupled analysis. The method 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 to more accurately capture environmental particulate matter on the filter membrane.

[0006] In order to achieve the above object, the present invention provides the following technical solution: an atmospheric particulate matter analysis method based on high and low accelerating voltage coupling 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 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;

[0008] Performing a second analysis on the environmental particulate matter sample by 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;

[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] According to the first particle position coordinate of each particle, obtain the distance from each particle to each of the three aiming points by calculation; according to the distance from each particle to each of the three aiming points, obtain the weight of the position coordinate difference of each of the three aiming points to each particle by calculation;

[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 of each particle and the position coordinates of each of the three aiming points through an inverse distance weighted 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 solution of the atmospheric particulate matter analysis method based on high and low acceleration voltage coupling analysis, in the process of obtaining the distance from each particle to each of the three aiming points by calculation according to 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 ith particle to the jth aiming point obtained in the first analysis; i and i is the position coordinate of the ith particle obtained from the first analysis; 1,j and1,j is the coordinate position of the j-th aiming point obtained by 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 of 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 calculation formula of the weight of each particle of the position coordinate difference of each aiming point is:

[0017]

[0018] In the formula, 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 and obtaining the predicted center coordinates of each particle when performing the second analysis by the inverse distance weighted strategy, the calculation formula for the predicted center coordinates of each particle when performing the second analysis is:

[0020]

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

[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 according to 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 ith particle obtained in the first analysis.

[0026] The present invention also provides an atmospheric particle analysis device based on high-low accelerating voltage coupling analysis, which adopts the above-mentioned atmospheric particle analysis method based on high-low accelerating voltage coupling analysis, including:

[0027] A low acceleration voltage analysis module 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 on the environmental particulate matter sample through the scanning electron microscope under a low acceleration 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 acceleration voltage analysis module, used for performing a second analysis on the environmental particulate matter sample through 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;

[0029] an aiming point position coordinate difference calculation and acquisition module, used for obtaining the position coordinate difference between the first aiming point position coordinate and the second aiming point position coordinate of the three aiming points by calculation;

[0030] an aiming point position coordinate difference weight calculation and acquisition module, configured to obtain the distance from each particle to each of the three aiming points by calculation according to the first particle position coordinate of each particle; and to obtain the weight of the position coordinate difference of each of the three aiming points to each particle by calculation according to the distance from each particle to each of the three aiming points;

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

[0032] The particle final analysis result acquisition module is used to calculate and obtain 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; 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 and low acceleration voltage coupling analysis, in the aiming point position coordinate difference weight calculation acquisition module, in the process of obtaining the distance from each particle to each of the three aiming points by calculation according to 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:

[0034]

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

[0036] As a preferred solution of the atmospheric particulate matter analysis device based on high and 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 each particle of 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 calculation formula of the weight of each particle of the position coordinate difference of each aiming point is:

[0037]

[0038] In the formula, 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 prediction center coordinate calculation acquisition module, in the process of calculating and acquiring the prediction center coordinates of each particle when performing the second analysis by the inverse distance weighted strategy, the calculation formula of the prediction center coordinates of each particle when performing the second analysis is:

[0040]

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

[0042] As a preferred solution of the atmospheric particulate matter analysis device based on high and low acceleration voltage coupling analysis, 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 according to 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 ith particle obtained in the first analysis.

[0046] The present invention has the following advantages: placing an environmental particulate matter sample into a scanning electron microscope sample chamber, and setting three aiming points in the area to be analyzed; performing a first analysis on the environmental particulate matter sample by the scanning electron microscope at a low acceleration voltage, recording and obtaining 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; performing a second analysis on the environmental particulate matter sample by 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 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; obtaining the distance from each particle to each of the three aiming points by calculation according to the first particle position coordinates of each particle; obtaining the distance from each particle to the three aiming points by calculating the distance from each particle to the three aiming points; obtaining the distance from each particle to the three aiming points by calculating the distance from each particle to the three aiming points; obtaining the distance from each particle to the three aiming points by calculating the distance from each particle to the three aiming points; obtaining the distance from each particle to the three aiming points by calculating the distance from each particle to the three aiming points. The distance of each aiming point in the point, calculate and obtain the weight of each particle of the position coordinate difference of each aiming point in the three aiming points; according to the weight of each particle of the first particle position coordinate of each particle and the position coordinate difference of each aiming point in the three aiming points, calculate and obtain the predicted center coordinate of each particle when performing the second analysis through the inverse distance weighted strategy; according to the maximum particle size data of each particle and the predicted center coordinate of each particle when performing the second analysis, calculate and obtain the coordinate range of each particle when performing the second analysis; according to the coordinate range of each particle when performing the second analysis, search for particles that meet the coordinate range in the second analysis results; according to the search results, process the analysis results of each particle to obtain the final analysis results of each particle in the environmental particulate matter. The present invention aims at the problem that the traditional computer-controlled scanning electron microscope energy spectrum technology has low recognition efficiency for particles with chemical composition similar to membrane composition when analyzing environmental particulate matter samples. The present invention can combine the advantages of computer-controlled scanning electron microscope-energy spectrum technology in elemental analysis capability at high acceleration voltage and imaging capability at low acceleration voltage to more accurately capture environmental particulate matter on the filter membrane. BRIEF DESCRIPTION OF THE DRAWINGS

[0047] In order to more clearly illustrate the implementation methods of the present invention or the technical solutions in the prior art, the drawings required for the implementation methods or the prior art descriptions are briefly introduced below. Obviously, the drawings in the following description are only exemplary, and for ordinary technicians in this field, other implementation drawings can be derived from the provided drawings without creative work.

[0048] The structures, proportions, sizes, etc. illustrated in this specification are only used to match the contents disclosed in the specification so as to facilitate understanding and reading by persons familiar with the technology. They are not used to limit the conditions under which the present invention can be implemented, and therefore have no substantial technical significance. Any structural modification, change in proportion or adjustment of size shall still fall within the scope of the technical contents disclosed in the present invention without affecting the effects and purposes that can be achieved by the present invention.

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

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

[0051] Figure 3 A schematic diagram of the setting of the particulate matter sample analysis area and aiming point 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 A schematic diagram of the analysis and imaging effect of a scanning electron microscope on carbonaceous particles under low accelerating voltage (5kev) and high accelerating voltage (20kev) conditions in the atmospheric particulate matter analysis method based on high and low accelerating voltage coupling analysis provided in Example 1 of the present invention;

[0053] Figure 5 A schematic diagram showing a comparison of 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 A schematic diagram of the architecture of an atmospheric particulate matter analysis device based on high and low accelerating voltage coupled analysis provided in Example 2 of the present invention. DETAILED DESCRIPTION

[0055] The following is a description of the implementation of the present invention by specific embodiments. People familiar with the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are 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 and low accelerating voltage coupling 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 on the environmental particulate matter sample by the scanning electron microscope at a low acceleration 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 by 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;

[0060] S3, obtaining the 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. Obtain the distance from each particle to each of the three aiming points by calculation according to the first particle position coordinates of each particle; and obtain the weight of the position coordinate difference of each of the three aiming points to each particle by calculation according to the distance from each particle to each of the three aiming points;

[0062] S5, according to the weight of each particle of the first particle position coordinate and the position coordinate difference of each of the three aiming points, calculate and obtain the predicted center coordinate of each particle when performing the second analysis through an inverse distance weighted strategy;

[0063] S6. Calculate and obtain 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; search for particles that meet the coordinate range in the second analysis results based on the coordinate range of each particle when performing the second analysis; and process the analysis results of each particle based on the search results to obtain the final analysis results of 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 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;

[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 of which are composed 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 first aiming point position coordinates (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 synchronously.

[0066] In this embodiment, in step S2, the environmental particulate matter sample is analyzed for 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), and the analysis area remained the same as the first step. The position coordinates (x 2,j ,y 2,j ), where j represents the jth aiming point. The second particle position coordinates of each particle analyzed are recorded at the same time. 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 according to 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 ith particle to the jth aiming point obtained in the first analysis; i and i is the position coordinate of the ith particle obtained from the first analysis; 1,j and 1,j is the coordinate position of the j-th aiming point obtained by the first analysis.

[0074] According to 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 is calculated;

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

[0076]

[0077] In the formula, 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 by using an inverse distance weighted strategy according to the weight of each particle based on 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] In the formula, x i ′ and y i ′ are the predicted center coordinates of the particle in the second analysis; Δx j and Δy j The position coordinate differences between the first aiming point position coordinates and the second aiming point position coordinates of the three aiming points are respectively.

[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 ith particle obtained in the first analysis.

[0087] According to the coordinate range of each particle during the second analysis, search for particles that meet the coordinate range in the second analysis results; based on the search results, process the analysis results of each particle to obtain the final analysis results of each particle in the environmental particulate matter.

[0088] Specifically, based on the above coordinate range, search for particles that meet the coordinate range in the second analysis results. If the corresponding particles can be retrieved, it means that the particles have been detected in both the previous and subsequent analyses, and the final analysis result is based on the second analysis result. On the contrary, if they are not retrieved, the particles are marked as "unmatched" particles, and the single particle image, particle size and chemical composition data of the particles are recorded. Combined with the second analysis results and the particles marked as "unmatched" in the first analysis results, the atmospheric particulate matter analysis results of the two analysis modes of high and low acceleration voltages are finally obtained.

[0089] In this embodiment, considering the high uncertainty of high atomic number elements under low accelerating voltage conditions, the present invention divides the first analyzed particles into two categories: carbonaceous particles (C-rich) and others (Other), and 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 only under high accelerating voltage, the computer-controlled scanning electron microscope energy spectrum technology can be used in PM1 and PM2. 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 according to the first particle position coordinates of each particle; obtains the maximum particle size data of each particle from the first aiming point position coordinates of each particle to the three aiming points according to the maximum particle size data of each particle. The weight of each particle of the position coordinate difference of each of the three aiming points is calculated; the predicted center coordinates of each particle when the second analysis is performed are calculated by the inverse distance weighting strategy according to the first particle position coordinate of each particle and the weight of each particle of the position coordinate difference of each of the three aiming points; the coordinate range of each particle when the second analysis is performed is calculated according to the maximum particle size data of each particle and the predicted center coordinates of each particle when the second analysis is performed; the particles that meet the coordinate range are searched in the second analysis results according to the coordinate range of each particle when the second analysis is performed; the analysis results of each particle are processed according to the search results to obtain the final analysis results of each particle in the environmental particulate matter. The present invention aims at the problem that the traditional computer-controlled scanning electron microscope energy spectrum technology has low recognition efficiency for particles with chemical compositions similar to membrane compositions when analyzing environmental particulate matter samples. The present invention can combine the advantages of computer-controlled scanning electron microscope-energy spectrum technology in elemental analysis capability at high acceleration voltage and imaging capability at low acceleration voltage to more accurately capture environmental particulate matter on the filter membrane.

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

[0092] It should be noted that the above describes some embodiments of the present disclosure. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recorded in the claims can be performed in an order different from that in the above embodiments and still achieve the desired results. In addition, the processes depicted in the accompanying drawings do not necessarily require the specific order or continuous order shown to achieve the desired results. In some 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 and low accelerating voltage coupling analysis, comprising:

[0095] The low acceleration voltage analysis module 001 is used to place the environmental particulate matter sample into the scanning electron microscope sample chamber and set three aiming points in the area to be analyzed; perform a first analysis on the environmental particulate matter sample through the scanning electron microscope under a low acceleration 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 is used to perform a second analysis on the environmental particulate matter sample through the scanning electron microscope under a high acceleration 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;

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

[0098] The aiming point position coordinate difference weight calculation and acquisition module 004 is used to obtain the distance from each particle to each of the three aiming points by calculation according to the first particle position coordinate of each particle; and to obtain the weight of the position coordinate difference of each of the three aiming points to each particle according to the distance from each particle to each of the three aiming points;

[0099] The particle prediction center coordinate calculation and acquisition module 005 is used to calculate and acquire the prediction center coordinate of each particle when performing the second analysis by using an inverse distance weighted strategy according to the weight of each particle based on the difference between the first particle position coordinate of each particle and the position coordinate of each of the three aiming points;

[0100] The particle final analysis result acquisition module 006 is used to calculate and obtain 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; 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 obtaining the distance from each particle to each of the three aiming points by calculation according to the first particle position coordinate of each particle, the calculation formula of the distance from each particle to each of the three aiming points is:

[0102]

[0103] Where, d i,j is the distance from the ith particle to the jth aiming point obtained in the first analysis; i and i is the position coordinate of the ith particle obtained from the first analysis; 1,j and 1,j is the coordinate position of the j-th aiming point obtained by 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 to each particle according to 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 to each particle is:

[0105]

[0106] In the formula, 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 prediction center coordinate calculation and acquisition module 005, in the process of calculating and acquiring the prediction center coordinate of each particle when performing the second analysis by the inverse distance weighted strategy, the calculation formula of the prediction center coordinate of each particle when performing the second analysis is:

[0108]

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

[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 according to 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 ith 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 in the previous part of the present application, and will not be repeated here.

[0115] Example 3

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

[0117] The computer-readable storage medium may be any available medium that can be accessed by a computer or a data storage device such as a server or a data center that includes one or more available media. The available medium may be a magnetic medium (e.g., a floppy disk, a hard disk, a tape), an optical medium (e.g., a DVD), or a semiconductor medium (e.g., a solid-state drive (SSD)).

[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 via 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 implemented by reading software codes stored in a memory. The memory can be integrated in the processor or can be 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 site, computer, server or data center by wired (e.g., coaxial cable, optical fiber, digital subscriber line (DSL)) or wireless (e.g., infrared, wireless, microwave, etc.) mode to another website site, computer, server or data center.

[0123] Obviously, those skilled in the art should understand that the above modules or steps of the present invention can be implemented by a general computing device, they can be concentrated on a single computing device, or distributed on a network composed of multiple computing devices, and optionally, they can be implemented by a program code executable by a computing device, so that they can be stored in a storage device and executed by the computing device, and in some cases, the steps shown or described can be executed in a different order than here, or they can be made into individual integrated circuit modules, or multiple modules or steps therein can be made into a single integrated circuit module for implementation. Thus, the present invention is not limited to any specific combination of hardware and software.

[0124] Although the present invention has been described in detail above by general description and specific embodiments, it is obvious to those skilled in the art that some modifications or improvements can be made to the present invention. Therefore, these modifications or improvements made without departing from the spirit of the present invention all belong to the scope of protection claimed by the present invention.

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 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; Performing a second analysis on the environmental particulate matter sample by 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; 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; According to the first particle position coordinate of each particle, obtain the distance from each particle to each of the three aiming points by calculation; according to the distance from each particle to each of the three aiming points, obtain the weight of the position coordinate difference of each of the three aiming points to each particle by calculation; 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 of each particle and the position coordinates of each of the three aiming points through an inverse distance weighted 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 coupling analysis according to claim 1 is characterized in that: In the process of obtaining the distance from each particle to each of the three aiming points by calculation according to 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 ith particle to the jth aiming point obtained in the first analysis; i and i is the position coordinate of the ith particle obtained from the first analysis; 1,j and 1,j is the coordinate position of the j-th aiming point obtained by the first analysis.

3. The atmospheric particulate matter analysis method based on high and low accelerating voltage coupling analysis according to claim 2 is characterized in that: In the process of calculating and obtaining the weight of each particle by 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 calculation formula of the weight of each particle by the position coordinate difference of each aiming point is: In the formula, 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 coupling analysis according to claim 3 is characterized in that: In the process of calculating and obtaining the predicted center coordinates of each particle when performing the second analysis by the inverse distance weighted strategy, the calculation formula of the predicted center coordinates of each particle when performing the second analysis is: In the formula, x i ′ and y i ′ are the predicted center coordinates of the particle in the second analysis; Δx j and Δy j The position coordinate differences between the first aiming point position coordinates and the second aiming point position coordinates of the three aiming points are respectively.

5. The atmospheric particulate matter analysis method based on high and low accelerating voltage coupling analysis according to claim 4 is characterized in that: In the process of calculating and obtaining the coordinate range of each particle during the second analysis according to 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 ith particle obtained in the first analysis.

6. An atmospheric particle analysis device based on high and low accelerating voltage coupling analysis, using the atmospheric particle analysis method based on high and low accelerating voltage coupling analysis described in claims 1-5 above, characterized in that: include: A low acceleration voltage analysis module 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 on the environmental particulate matter sample through the scanning electron microscope under a low acceleration 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 acceleration voltage analysis module, used for performing a second analysis on the environmental particulate matter sample through 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; an aiming point position coordinate difference calculation and acquisition module, used for obtaining the position coordinate difference between the first aiming point position coordinate and the second aiming point position coordinate of the three aiming points by calculation; an aiming point position coordinate difference weight calculation and acquisition module, configured to obtain the distance from each particle to each of the three aiming points by calculation according to the first particle position coordinate of each particle; and to obtain the weight of the position coordinate difference of each of the three aiming points to each particle by calculation according to the distance from each particle to each of the three aiming points; a particle prediction center coordinate calculation and acquisition module, configured to calculate and acquire the prediction center coordinate of each particle during the second analysis by using an inverse distance weighted strategy according to the weight of each particle based on the difference between the first particle position coordinate of each particle and the position coordinate of each of the three aiming points; The particle final analysis result acquisition module is used to calculate and obtain 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; 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 coupling analysis according to claim 6, characterized in that: In the aiming point position coordinate difference weight calculation and acquisition module, in the process of obtaining the distance from each particle to each of the three aiming points by calculation according to 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 ith particle to the jth aiming point obtained in the first analysis; i and i is the position coordinate of the ith particle obtained from the first analysis; 1,j and 1,j is the coordinate position of the j-th aiming point obtained by the first analysis.

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

10. The atmospheric particulate matter analysis device based on high and low accelerating voltage coupling 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 according to 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 ith particle obtained in the first analysis.

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