JP2020201148A - Analyzer and x-ray diffraction device - Google Patents

Abstract

To provide an analyzer that increases the efficiency of analyzing asbestos and free silicic acid in a work environment measurement.SOLUTION: An X-ray diffraction device in one embodiment of the present invention comprises: a database 22 in which the standard X-ray diffraction patterns of a large number of known substances are recorded; candidate extraction units 24, 25 for evaluating the similarity of a measured X-ray diffraction pattern obtained by analyzing a sample with the standard X-ray diffraction pattern of each substance recorded in the database and extracting a substance that indicates a standard X-ray diffraction pattern having high similarity as an identification candidate; and a display processing unit 26 for creating a display screen on which are arranged a first display column for displaying information of one or a plurality of identification candidates extracted by the candidate extraction units, a second display column for displaying information of one or a plurality of predetermined specific substances, out of the substances recorded in the database, including the result of similarity evaluation by the candidate extraction units, and a waveform display column for displaying the measured X-ray diffraction pattern, the created display screen being displayed by a display unit 4.SELECTED DRAWING: Figure 1

Description

The present invention relates to an analyzer and an X-ray diffractometer for identifying a specific substance contained in a sample.

In order to prevent health hazards for workers working in a dusty work environment, Japan is obliged to carry out work environment measurements for specific substances that may cause health hazards. .. Among such substances, an X-ray diffractometer is used for qualitative analysis and quantitative analysis of free silicic acid and asbestos (see Non-Patent Documents 1 and 2).

In the X-ray diffractometer, a sample such as powder is irradiated with X-rays having a predetermined wavelength, and diffracted X-rays generated by scattering or interfering with electrons belonging to atoms constituting the sample are detected by a detector. .. The diffraction angle at this time depends on the lattice spacing of the substance, and the diffraction intensity depends on the arrangement state and atomic species of atoms and molecules. Therefore, when the sample is irradiated with X-rays of a known wavelength and the relationship between the diffraction angle of the diffracted X-rays obtained from the sample and the X-ray intensity is obtained, a peak of the X-ray intensity is observed near a predetermined diffraction angle. The X-ray diffraction pattern to be obtained is obtained. By comparing the X-ray diffraction pattern obtained by such actual measurement with the X-ray diffraction pattern of a known substance, the substance contained in the sample can be identified (see Patent Document 1 and the like).

In the actual X-ray diffractometer described in Non-Patent Document 2 and the like, the actual X-ray diffraction pattern and the standard X-ray diffraction of various substances recorded in the database are used by the identification software operating on the computer. Substances that have been evaluated for similarity to the pattern and determined to have high similarity are displayed as identification candidates in a list on the screen of the display unit. For example, the user confirms the consistency between the X-ray diffraction pattern of the identification candidate substance and the actually measured X-ray diffraction pattern on the screen, and further, it is contained in the sample based on the knowledge and experience of the sample to be analyzed. Identify the substance in question, that is, determine whether the identification candidate is the correct substance.

JP-A-2018-21836

"Working Environment Measurement Guidebook 1 Mineral Dust / Asbestos / RCF", Japan Working Environment Measurement Association, September 25, 2018, 6th Edition "XRD-6100 Ideal for qualitative and quantitative analysis of free silicic acid and asbestos in the working environment.", [Online], Shimadzu Corporation, [Searched on March 26, 2019], Internet <URL: https: //www.an.shimadzu.co.jp/surface/xd/use04.htm ＞

However, the conventional X-ray diffractometer has the following problems.
In general, the number of substances recorded in the database for substance identification in X-ray diffraction is very large. For example, the mineral subfile of "ICDD PDF-2 2018", which is a typical powder X-ray diffraction database used for identifying asbestos and the like, contains a huge number of substances of about 30,000. In addition, many of the X-ray diffraction patterns of such a huge number of substances have considerably similar waveform shapes. As a result, a fairly large number of candidates are usually displayed as a result of an automatic search by the identification software.

When asbestos and free silicic acid contained in a powder sample such as a building material are analyzed, the sample contains a wide variety of impurities other than those target substances. Therefore, in the list of substance candidates, there are many candidates for contaminants in addition to the target substance. Since the user needs to perform the identification work while confirming the X-ray diffraction pattern one by one for such a large number of candidates, the work is very complicated and time-consuming. In addition, if the number of candidate substances on the list is limited, candidates for target substances such as asbestos and free silicic acid may be omitted from the list.

In particular, asbestos is usually contained in a small amount even if it is contained in dust or the like emitted from a construction site. Therefore, in X-ray diffraction, the three strong lines (up to the third peak in descending order of relative intensity) that characterize a substance are often small, and therefore the standard X-ray diffraction pattern of the correct substance recorded in the database. It may be difficult to identify asbestos due to its low similarity to.

The present invention has been made to solve the above problems, and an object of the present invention is to identify a specific substance such as asbestos or free silicic acid based on an analysis result such as an X-ray diffraction pattern. It is an object of the present invention to provide an analyzer and an X-ray diffractometer capable of identifying a substance efficiently and with high accuracy by reducing troublesome work by a user.

The first aspect of the analyzer according to the present invention, which has been made to solve the above problems, is an analyzer that identifies a substance contained in the sample by using a waveform pattern obtained by analyzing the sample. There,
A database containing standard waveform patterns for many known substances,
A substance that evaluates the similarity between the measured waveform pattern obtained by analyzing the sample and the standard waveform pattern of each substance recorded in the database, and shows a standard waveform pattern with high similarity. Candidate extraction unit that extracts
The first display column for displaying information on one or more identification candidates extracted by the candidate extraction unit, and the candidate for a specific one or more substances predetermined among the substances recorded in the database. A display processing unit that creates a display screen in which a second display column for displaying information on the substance including the evaluation result of similarity in the extraction unit is arranged and displays it on the display unit,
Is provided.

The first aspect of the X-ray diffractometer according to the present invention, which has been made to solve the above problems, identifies a substance contained in the sample by using the X-ray diffraction pattern obtained by analyzing the sample. X-ray diffractometer
A database containing standard X-ray diffraction patterns of many known materials, and
The similarity between the actually measured X-ray diffraction pattern obtained by analyzing the sample and the standard X-ray diffraction pattern of each substance recorded in the database is evaluated, and the standard X with high similarity is evaluated. A candidate extraction unit that extracts substances showing a line diffraction pattern as identification candidates,
The first display column for displaying information on one or more identification candidates extracted by the candidate extraction unit, and the candidate for a specific one or more substances predetermined among the substances recorded in the database. A display screen is created in which a second display column for displaying information on the substance including the evaluation result of similarity in the extraction unit and a waveform display column for displaying the actually measured X-ray diffraction pattern are arranged. The display processing unit to be displayed on the display unit and
Is provided.

In the X-ray diffractometer according to the present invention, a predetermined specific substance or a plurality of substances can be classified into asbestos and free silicic acid.

In the analyzer or X-ray diffractometer of the first aspect according to the present invention, such an object is determined in advance so that the target substance to be inspected, such as asbestos or free silicic acid, is displayed in the second display column. Even when a large number of candidate substances for contaminants with higher similarity in waveform pattern (X-ray diffraction pattern) than substances are extracted, the user can use the second display column to evaluate the similarity of the target substance. Can be confirmed. As a result, it is possible to quickly confirm the consistency of the waveform pattern as necessary from the result of the similarity evaluation of the target substance, and identify the target substance, that is, it takes less time and effort to identify whether or not the target substance is contained in the sample. You can check it efficiently with.

In addition, the similarity between the actually measured waveform pattern and the standard waveform pattern of the target substance is relatively low, and if it is displayed in the first display column, it may be displayed at a considerably lower level or displayed due to restrictions on the number of displays. According to the present invention, the target substance is displayed in the second display column, so that identification can be performed with high accuracy even if the target substance is not displayed. Furthermore, with respect to impurities other than the target substance, detailed identification work can be performed as in the conventional case based on the information displayed in the first display column.

The block diagram of the main part of the X-ray diffractometer which is one Embodiment of this invention. The explanatory view of the display processing of the automatic search result in the X-ray diffractometer of this embodiment. The figure which shows an example of the display screen of the automatic search result in the X-ray diffractometer of this embodiment.

Hereinafter, the X-ray diffractometer according to the embodiment of the present invention will be described with reference to the accompanying drawings.

FIG. 1 is a block diagram of a main part of the X-ray diffractometer of the present embodiment.
As shown in FIG. 1, the X-ray diffractometer of the present embodiment includes an X-ray diffraction measuring unit 1, a data processing unit 2, an input unit 3, and a display unit 4.

The X-ray diffraction measurement unit 1 includes an X-ray irradiation unit 11 including an X-ray tube, a goniometer 12, a sample holder 13, and an X-ray detection unit 14. The sample 15 is installed so that its surface is at the center of the goniometer 12. The goniometer 12 has an angle θ formed by the X-rays incident on the sample 15 from the X-ray irradiation unit 11 and the surface (crystal plane) of the sample 15 and the emitted X-rays toward the surface of the sample 15 and the X-ray detection unit 14. The sample holder 13 and the X-ray detector 14 are rotated so that the angles θ formed are always equal to each other. An X-ray diffraction pattern can be obtained by performing such angle scanning and obtaining the relationship between the rotation angle 2θ and the X-ray intensity.
The X-ray diffraction measuring unit 1 may be an energy dispersion type X-ray diffractometer instead of such an angle scanning type X-ray diffractometer.

The data processing unit 2 includes an X-ray diffraction pattern creation unit 21, an identification database 22, a specific substance information storage unit 23, a substance search processing unit 24, a pattern similarity evaluation unit 25, and a search result display processing unit 26 as functional blocks. And so on. The identification database 22 may be used according to the type of the substance to be analyzed, and when analyzing asbestos / free silicic acid, which will be described later, the identification database 22 may be, for example, the above-mentioned "ICDD PDF-2 2018". Mineral subfiles can be used. In FIG. 1, the identification database 22 is included in the data processing unit 2, but the identification database 22 may be provided outside the data processing unit 2 so as to be accessible from the data processing unit 2.

Normally, the substance of the data processing unit 2 is a personal computer in which dedicated data processing software is installed, and the functions of the above functional blocks are achieved by operating the software on the computer. can do.

Next, a characteristic processing operation in the case of analyzing asbestos / free silicic acid using the X-ray diffractometer of the present embodiment will be described with reference to FIGS. 1 and 2. FIG. 2 is an explanatory diagram of display processing of an automatic search result in the X-ray diffractometer of the present embodiment.

The X-ray diffraction measurement unit 1 executes X-ray diffraction on the sample 15 to be analyzed, and the data obtained by the X-ray detection unit 14 is input to the data processing unit 2. In the data processing unit 2, the X-ray diffraction pattern creation unit 21 creates a waveform graph of an X-ray diffraction pattern in which the horizontal axis is the diffraction angle and the vertical axis is the X-ray intensity. Further, the X-ray diffraction pattern creation unit 21 executes peak detection according to a predetermined peak detection algorithm in the graph, and obtains a line peak corresponding to each detected peak. The position of the line peak indicates the diffraction angle, and the height of the line peak indicates the X-ray intensity at the diffraction angle.

The substance search processing unit 24 reads out the compound information recorded in the identification database 22 in order, and the pattern similarity evaluation unit 25 obtains a standard X-ray diffraction pattern associated with each compound by the above-mentioned actual measurement. The index value (hereinafter referred to as "similarity") indicating the similarity of the waveform shape or the line peak pattern is calculated according to a predetermined algorithm by comparing with the obtained X-ray diffraction pattern. The higher the similarity, the larger the similarity. In the conventional X-ray diffractometer, for example, compounds having a similarity equal to or higher than a predetermined threshold value are selected from all the compounds recorded in the identification database 22, and are listed as candidate substances in descending order of similarity. It is displayed on the screen of the display unit 4. On the other hand, in the apparatus of this embodiment, the following characteristic processing is performed.

As shown in FIG. 2A, the identification database 22 contains related information such as a compounding formula and information such as a standard X-ray diffraction pattern for a huge number of compounds. On the other hand, the specific substance information storage unit 23 stores information on a specific compound designated in advance corresponding to the asbestos / free silicic acid analysis among the compounds recorded in the identification database 22. Since the information stored in the specific substance information storage unit 23 may be associated with the information stored in the identification database 22, for example, only the compound name or a number for specifying each compound (example). As the card number shown in FIG. 3 described later, only the card number) may be stored. Alternatively, as shown in FIG. 2B, the same information contained in the identification database 22 may be stored for the specified specific compound.

Since the specific compound differs depending on the purpose of analysis such as asbestos / free silicic acid analysis, for example, the manufacturer of this device or the manufacturer providing data processing software should determine a specific compound in advance for each analysis purpose. It should be. In that case, when the user indirectly or directly selects the analysis purpose by using the application software according to the analysis purpose, a specific compound suitable for the analysis purpose may be automatically selected. In addition, the user may newly specify a specific compound, or delete or add a part of a specific compound that has already been registered.

As an example, in the case of asbestos / free silicic acid analysis, a compound as described in Non-Patent Document 1 may be defined as a specific compound. Specifically, the compounds (substances) classified as free silicic acid include quartz (Q), cristobalite (Cr), tridimite (Tr) and the like. In addition, as compounds (substances) classified as asbestos, chrysotile (Chr), crocidolite (Cro), amosite (Amo), tremolite (Tre), actinolite (Act), anthophyllite (Ant), sepiolite (Se), etc. Is included.

The substance search processing unit 24 and the pattern similarity evaluation unit 25 actually measure the standard X-ray diffraction pattern associated with each compound recorded in the identification database 22 as in the conventional device. Compare with the pattern and calculate the similarity of the waveform shape or line peak pattern according to a predetermined algorithm. Therefore, the degree of similarity can be obtained for each compound recorded in the identification database 22.

The search result display processing unit 26 creates a search result display screen 100 as shown in FIG. 2C. On the search result display screen 100, a profile display field 101, a processed graph display field 102, a specific compound list display field 103, and a general compound list display field 104 are arranged. In the profile display field 101, a waveform graph (profile) of the X-ray diffraction pattern obtained by actual measurement is displayed. Since this profile is obtained before the processing by the substance search processing unit 24 is executed, when the sample or the like to be identified is specified on the search result display screen 100, the profile is displayed in the profile display field 101.

In the specific compound list display column 103, a list showing a list of compound-related information and similarities for the above-mentioned specific compound is displayed. The similarity cannot be obtained until the processing by the substance search processing unit 24 is completed, but since the compounds in the list displayed in the specific compound list display column 103 are fixed, the profile display column 101 as described above. At the same time that the profile is displayed in the specific compound list display field 103, a list in which other compound-related information is posted except for the similarity information may be displayed.

In the general compound list display column 104, a list showing compound-related information and similarity is displayed for compounds whose similarity is equal to or higher than a predetermined threshold among all the compounds recorded in the identification database 22. Will be done. The compounds displayed in this list are not determined until the treatment by the substance search processing unit 24 is completed and the similarity is obtained. Therefore, the list is displayed after the time when the processing by the substance search processing unit 24 is completed and the similarity is obtained.

Further, the processed graph display column 102 is designated by the user in the graph of the line peak calculated from the actually measured X-ray diffraction pattern, the list displayed in the specific compound list display column 103 and the general compound list display column 104. The line peak graph of the standard X-ray diffraction pattern of the compound, the peak difference graph which is the result of calculating the difference between the above two line peak graphs, and the superimposition of the peak graphs of all the compounds determined to be contained, Etc. are displayed. These graphs are used when the user confirms the X-ray diffraction pattern of the candidate substance extracted as a result of the search in detail and identifies the compound.

Similarity of X-ray diffraction pattern to each compound (for example, compounds A, B, C, ... In FIG. 2A) recorded in the identification database 22 by the substance search processing unit 24 and the pattern similarity evaluation unit 25. When the degree is obtained, the search result display processing unit 26 selects a compound having a similarity equal to or higher than a predetermined threshold among all the compounds, and creates a list as a candidate substance in descending order of similarity. It is displayed in the general compound list display field 104.

In parallel with this, the search result display processing unit 26 transfers the substance search processing unit 24 for each compound (for example, the compounds a, b, c, ... In FIG. 2B) stored in the specific substance information storage unit 23. And the similarity calculated by the pattern similarity evaluation unit 25 is selected, a list of specific compounds is created, and the list is displayed in the specific compound list display column 103. Alternatively, as described above, when the profile is displayed in the profile display field 101 and the list is displayed in the specific compound list display field 103 at the same time, the similarity of each compound is added to the list.

As a result, in the case of asbestos / free silicic acid analysis, compound-related information and X-ray diffraction for compounds of interest to users such as quartz, cristovalite, tridimite, chrysotile, crocidolite, amosite, tremolite, actinolite, anthophyllite, and sepiolite A list including the similarity of the pattern as information is displayed in the specific compound list display column 103 separately from the list of other compounds. In the list displayed in the specific compound list display column 103, the order of each compound may be rearranged in descending order of similarity value, or the compounds may be arranged in a predetermined order regardless of the magnitude of similarity. Good. In any case, even for compounds in which the amount contained in the sample is very small and the similarity between the actually measured X-ray diffraction pattern and the standard X-ray diffraction pattern is low, the list in the specific compound list display column 103 The compound information and similarity of the compound are displayed in.

FIG. 3 is a diagram showing an example of an actual search result display screen 100. The graphs or lists as described above are displayed in the display fields 101 to 104 in the search result display screen 100, respectively. R in the list is a value corresponding to the degree of similarity.

In this way, when the user specifies one compound in the list displayed in the specific compound list display field 103 or in the list in the general compound list display field 104 by a click operation by the input unit 3, the search result display processing unit 26 is a peak obtained by calculating the difference between the line peak graph obtained from the standard X-ray diffraction pattern of the specified compound and the line peak graph obtained from the measured X-ray diffraction pattern. The difference graph is displayed in the graph display field 102 after processing. By checking these graphs, the user can examine in detail whether or not the sample contains a specific compound in the list displayed in, for example, the specific compound list display field 103.

On the other hand, in the list displayed in the general compound list display column 104, compound-related information and similarities for various compounds including compounds other than asbestos and free silicic acid are displayed in descending order of similarity. .. Therefore, the identification work for impurities contained in the sample, such as the main substance of the building material, can be performed in the same manner as in the conventional case. When it is not necessary to analyze compounds other than asbestos and free silicic acid, the list displayed in the general compound list display field 104 may be ignored.

The substance search processing unit 24 and the pattern similarity evaluation unit 25 give priority to the degree of similarity between the standard X-ray diffraction pattern of each compound stored in the specific substance information storage unit 23 and the actually measured X-ray diffraction pattern. The search result display processing unit 26 displays the result in the list in the specific compound list display field 103, and then displays the X-ray diffraction pattern for each compound recorded in the identification database 22. The similarity may be calculated. This makes it possible to quickly confirm the search results for specific compounds classified as asbestos and free silicic acid.

It should be noted that the above embodiment is an example of the present invention, and it is clear that the present invention is included in the claims even if it is appropriately modified, changed or added within the scope of the present invention.

For example, in the description of the above embodiment, the X-ray diffractometer was used for the analysis of asbestos and free silicic acid in the working environment measurement, but it is also conceivable to use the X-ray diffractometer for the analysis in other fields such as product quality control. Be done. In the case of product quality control, one or more compounds to be controlled or reported may be selected as a specific compound, whereby the work efficiency of quality control can be improved.

Further, in the above embodiment, the analyzer according to the present invention is applied to an X-ray diffractometer, but in the present invention, a graph showing some waveform shape by analyzing a sample, for example, an X-ray absorption spectrum or an absorption spectrum. , Acquire a mass spectrum, or chromatogram, compare its waveform shape, peak position, etc. with a standard graph of a known substance, evaluate the similarity, and identify the substance based on the result. It can also be applied to the analyzer of.

[Various aspects]
It will be apparent to those skilled in the art that the exemplary embodiments described above are specific examples of the following embodiments.

The first aspect of the analyzer according to the present invention is an analyzer that identifies a substance contained in the sample by using a waveform pattern obtained by analyzing the sample.
A database containing standard waveform patterns for many known substances, and
A substance that evaluates the similarity between the measured waveform pattern obtained by analyzing the sample and the standard waveform pattern of each substance recorded in the database, and shows a standard waveform pattern with high similarity. Candidate extraction unit that extracts
The first display column for displaying information on one or more identification candidates extracted by the candidate extraction unit, and the candidate for a specific one or more substances predetermined among the substances recorded in the database. A display processing unit that creates a display screen in which a second display column for displaying information on the substance including the evaluation result of similarity in the extraction unit is arranged and displays it on the display unit,
Is provided.

A first aspect of the X-ray diffractometer according to the present invention is an X-ray diffractometer that identifies a substance contained in the sample by using an X-ray diffraction pattern obtained by X-ray diffraction analysis of the sample. hand,
A database containing standard X-ray diffraction patterns of many known materials, and
The similarity between the actually measured X-ray diffraction pattern obtained by analyzing the sample and the standard X-ray diffraction pattern of each substance recorded in the database is evaluated, and the standard X with high similarity is evaluated. A candidate extraction unit that extracts substances showing a line diffraction pattern as identification candidates,
The first display column for displaying information on one or more identification candidates extracted by the candidate extraction unit, and the candidate for a specific one or more substances predetermined among the substances recorded in the database. A display screen is created in which a second display column for displaying information on the substance including the evaluation result of similarity in the extraction unit and a waveform display column for displaying the actually measured X-ray diffraction pattern are arranged. The display processing unit to be displayed on the display unit and
Is provided.

According to the analyzer or the X-ray diffractometer according to the first aspect, by appropriately defining one or more specific substances according to the purpose of analysis and the like, the waveform pattern (X) is compared with the specific substance. Even when many candidate substances for contaminants with higher similarity of (X-ray diffraction pattern) are extracted, the user confirms the result of similarity evaluation of a specific substance from the information displayed in the second display column. can do. As a result, it is possible to identify the target substance, that is, to efficiently confirm whether or not the target substance is contained in the sample with little effort. That is, it is possible to reduce the work load of the user for identifying the substance in the sample and shorten the work time.

In addition, even if the similarity of the waveform pattern (X-ray diffraction pattern) is low because the amount of the target substance in the sample is very small, such a substance can be identified as a candidate substance without omission. It can be performed. As a result, the substance in the sample can be identified with high accuracy. Of course, it is possible to carry out detailed identification work on impurities other than the target substance as in the conventional case.

The X-ray diffractometer according to the second aspect of the present invention is the X-ray diffractometer according to the first aspect, wherein the specific one or more substances are substances classified into asbestos and free silicic acid. be able to.

According to this second aspect, qualitative analysis and quantitative analysis of asbestos and free silicic acid in the working environment measurement can be efficiently performed.

1 ... X-ray diffraction measurement unit 11 ... X-ray irradiation unit 12 ... Goniometer 13 ... Sample holder 14 ... X-ray detection unit 15 ... Sample 2 ... Data processing unit 21 ... X-ray diffraction pattern creation unit 22 ... Identification database 23 ... Identification Material information storage unit 24 ... Material search processing unit 25 ... Pattern similarity evaluation unit 26 ... Search result display processing unit 3 ... Input unit 4 ... Display unit 100 ... Search result display screen 101 ... Profile display field 102 ... Post-processing graph display field 103 ... Specific compound list display field 104 ... General compound list display field

Claims (3)

An analyzer that identifies substances contained in the sample by using the waveform pattern obtained by analyzing the sample.
A database containing standard waveform patterns for many known substances, and
A substance that evaluates the similarity between the measured waveform pattern obtained by analyzing the sample and the standard waveform pattern of each substance recorded in the database, and shows a standard waveform pattern with high similarity. Candidate extraction unit that extracts
The first display column for displaying information on one or more identification candidates extracted by the candidate extraction unit, and the candidate for a specific one or more substances predetermined among the substances recorded in the database. A display processing unit that creates a display screen in which a second display column for displaying information on the substance including the evaluation result of similarity in the extraction unit is arranged and displays it on the display unit,
An analyzer equipped with. An X-ray diffractometer for identifying a substance contained in a sample by using an X-ray diffraction pattern obtained by X-ray diffraction analysis of the sample.
A database containing standard X-ray diffraction patterns of many known materials, and
The similarity between the actually measured X-ray diffraction pattern obtained by analyzing the sample and the standard X-ray diffraction pattern of each substance recorded in the database is evaluated, and the standard X with high similarity is evaluated. A candidate extraction unit that extracts substances showing a line diffraction pattern as identification candidates,
The first display column for displaying information on one or more identification candidates extracted by the candidate extraction unit, and the candidate for a specific one or more substances predetermined among the substances recorded in the database. A display screen is created in which a second display column for displaying information on the substance including the evaluation result of similarity in the extraction unit and a waveform display column for displaying the actually measured X-ray diffraction pattern are arranged. The display processing unit to be displayed on the display unit and
An X-ray diffractometer comprising. The X-ray diffractometer according to claim 2, wherein the specific one or more substances are substances classified into asbestos and free silicic acid.

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