JP7208882B2 - Powder sample cell, fluorescent X-ray analyzer and fluorescent X-ray analysis method - Google Patents

Description

The present invention provides a powder sample cell used for fluorescent X-ray analysis of a powder sample, a fluorescent X-ray analysis apparatus equipped with the powder sample cell, and a fluorescent X-ray analysis using the powder sample cell. It is about the method.

In the X-ray fluorescence analysis, when the object to be analyzed is a powder sample, a technique is often used in which an additive such as a binder is added to the powder sample, pressed and molded into a tablet shape, and then X-ray fluorescence analysis is performed. . This is because the powder sample must have a uniform density and a certain thickness in order to improve the measurement accuracy.

However, when an additive is added, there is a problem that, among the elements constituting the powder sample, the element overlapping with the element contained in the additive cannot be analyzed.

In the case of performing fluorescent X-ray analysis without adding an additive to a powder sample, a method of placing the powder sample on a film and performing fluorescent X-ray analysis, or a holder as shown in Patent Document 1 A technique is known in which a powder sample is inserted into the tube, covered with a film, and fluorescent X-ray analysis is performed through the film.

However, in the former method, the thickness required for quantitative analysis of the powder sample cannot be created, and the density becomes sparse, so there is a problem that accurate quantitative analysis is difficult.

The latter method has the problem that the fluorescent X-ray emitted from the powder sample is absorbed by the film before it reaches the detector, and the accuracy of analysis of elements in the wavelength range that is easily absorbed by the film is lowered. For example, since fluorescent X-rays of light elements such as Na and Mg are easily absorbed by the film, the analysis accuracy of light elements is reduced. Furthermore, when the amount of the powder sample is very small, the intensity of the fluorescent X-rays is originally weak, so the absorption of the fluorescent X-rays by the film significantly affects the analysis accuracy. In addition, in the latter method, the X-rays transmitted through the powder sample hit the bottom surface of the holder in which the powder sample is inserted and are reflected and scattered. There is also the problem of ground noise.

JP-A-2000-230912

The present invention has been made in view of the above-mentioned problems, and without additives such as binders, for example, even a light element or a trace amount of powder sample can be quantitatively analyzed with high accuracy using fluorescent X-rays. A primary object of the present invention is to provide a powder sample cell capable of

That is, the powder sample cell according to the present invention is used for fluorescent X-ray analysis in which a powder sample is irradiated with primary X-rays from above and fluorescent X-rays emitted upward from the powder sample are detected. A surrounding member having an upper surface and a lower surface, and a through hole communicating between the upper surface and the lower surface is formed at a predetermined location; and an X-ray transparent film attached to the lower surface of the surrounding member, It is characterized in that the inner peripheral surface of the through-hole and the X-ray transmissive film form a sample-accommodating space whose upper surface is open.

With such a powder sample cell, by filling the sample storage space with the powder sample, it is possible to obtain uniformity in thickness and density necessary for quantitative analysis even for powder samples to which additives such as binders cannot be added. can be done. In addition, since the upper surface of the sample storage space is open, the fluorescent X-rays emitted from the powder sample reach the detector without being absorbed by an object such as a film. It is possible to improve the accuracy of quantitative analysis also for Furthermore, since the bottom surface of the sample storage space is formed of the X-ray transparent film, it is possible to suppress reflection and scattering of X-rays from the bottom surface of the sample storage space. As a result, background noise in fluorescent X-ray detection can be reduced.

It is preferable that the X-ray transparent film contains a resin.

With such a configuration, the X-rays are less likely to be scattered by the X-ray transmission film forming the sample accommodation space, so that the background noise in fluorescent X-ray detection can be further reduced.

A specific aspect of the surrounding member is a flat plate having one or more through holes.

With such a configuration, it is possible to easily produce the surrounding member as described above.
Moreover, when the surrounding member has a plurality of through-holes, one type of powder sample can be put into each through-hole independently, so that the powder samples are not mixed with each other. As a result, by distinguishing and analyzing these powder samples according to the positions of the through-holes, it is also possible to analyze a plurality of types of powder samples at once.

The powder sample cell further comprises a supporting member that sandwiches and supports the X-ray transmissive film between itself and the lower surface of the surrounding member, and the supporting member is provided with a hollow portion whose upper surface is open at least. It is preferable that the through-hole is positioned inside the cavity when viewed from a direction perpendicular to the X-ray transparent film.

With such a configuration, the X-ray transmissive film can be supported by the supporting member without increasing background noise in fluorescent X-ray detection. As a result, it is possible to prevent the X-ray transmissive film from coming off, and to restrain the deterioration of analysis accuracy caused by the bending of the X-ray transmissive film.
In addition, since the support member is located under the X-ray transparent film, for example, a member that scatters X-rays may be arranged under the X-ray transparent film, which is the bottom portion of the sample housing space. , it can prevent the background noise from increasing due to human error.

As a specific mode of the support member, one having a flat plate shape and the hollow portion being one or a plurality of holes penetrating in the thickness direction can be mentioned.

With this configuration, the hollow portion is formed simply by piercing the through hole in the flat plate material, so that the support member can be easily manufactured. In addition, since the cavity is a hole penetrating the support member in its thickness direction, background noise due to reflected and scattered X-rays can be further reduced compared to the case where the cavity has a bottom. .

Fluorescence comprising a powder sample cell according to the present invention, an irradiation mechanism for irradiating primary X-rays, and a detector for detecting fluorescent X-rays generated when the powder sample is irradiated with primary X-rays With an X-ray analyzer, even for powder samples that cannot be added with a binder, X-ray fluorescence analysis can be performed while ensuring the thickness and uniformity of the powder sample. Analysis accuracy can be improved.

Furthermore, if the fluorescent X-ray spectrometer is provided with a sample chamber for accommodating the powder sample cell and a decompression mechanism for reducing the pressure in the sample chamber, the decompression mechanism reduces or evacuates the sample chamber. Therefore, it is possible to suppress the absorption of the fluorescent X-rays by the air present in the sample chamber, thereby further improving the analysis accuracy.

As positions of the powder sample cell in the sample chamber, an irradiation position, which is a position at which the powder sample inserted into the powder sample cell is irradiated with primary X-rays from the irradiation mechanism, and the irradiation position. and an installation position, which is a position where the powder sample cell is placed before irradiation, is separately provided, and a moving mechanism for moving the powder sample cell between the irradiation position and the installation position is further provided. The decompression mechanism is provided with an exhaust port formed in the wall of the sample chamber for exhausting the air in the sample chamber, and the distance between the installation position and the exhaust port is greater than the distance between the irradiation position and the exhaust port. With the fluorescent X-ray spectrometer characterized by It is possible to prevent scattering from the cell.

According to the present invention, the components of a powder sample can be accurately quantitatively analyzed using fluorescent X-rays, even for a powder sample containing light elements or trace amounts, without additives such as binders. A sample cell can be provided.

1 is a diagram schematically showing the overall configuration of a fluorescent X-ray spectrometer according to this embodiment; FIG. The figure which shows typically the powder sample cell which concerns on the same embodiment. FIG. 2 is a schematic diagram of the powder sample cell according to the same embodiment as viewed from above; FIG. 2 is a schematic cross-sectional view of the powder sample cell according to the same embodiment; 4 is a flowchart showing the operation and analysis procedure of the fluorescent X-ray spectrometer of the same embodiment; FIG. 4 is a diagram schematically showing a powder sample cell according to another embodiment of the present invention; Schematic diagram and cross-sectional schematic diagram when the powder sample cell according to the other embodiment is viewed from above.

A powder sample cell 1 and a fluorescent X-ray analyzer 100 according to an embodiment of the present invention will be described below with reference to the drawings. It should be noted that the powder sample cell 1 and the fluorescent X-ray analyzer 100 described below do not limit the present invention to the following unless otherwise specified. Also, the sizes and positional relationships of members shown in each drawing may be deformed for easy understanding.

The X-ray fluorescence spectrometer 100 of this embodiment is for analyzing trace amounts of powder such as sand, rocks, minerals, or pharmaceuticals, and as shown in FIG. and detects the fluorescent X-rays emitted upward from the powder sample P to perform quantitative analysis of the elements contained in the sample. It is an analyzer. In this specification, "upward" includes not only the vertical direction but also the oblique direction with respect to the vertical direction.

Specifically, the X-ray fluorescence spectrometer 100 includes a powder sample cell 1 containing a powder sample P, a sample chamber 2 containing the powder sample cell 1, and the An X-ray irradiation mechanism 3 that irradiates a powder sample P with primary X-rays, and a detection unit that detects fluorescent X-rays generated from the powder sample P by irradiation of the primary X-rays from the X-ray irradiation mechanism 3. 4 and an information processing device 5 for quantitatively analyzing the components in the powder sample P based on the fluorescent X-rays detected by the detection unit 4 .
Each part will be described below.

The powder sample cell 1 accommodates the powder sample P as described above. Details of the powder sample cell 1 will be described later.

The sample chamber 2 has therein an irradiation position 2a, which is the position of the powder sample cell 1 when the powder sample P is irradiated with X-rays.

The X-ray irradiation mechanism 3 includes, for example, an X-ray generator 31 and an X-ray conduit 32 that guides the X-rays generated by the X-ray generator 31 to the powder sample P. As shown in FIG.

The X-ray generator 31 has, for example, an X-ray tube, and generates X-rays by exciting a target metal with thermal electrons generated from the X-ray tube.

The X-ray conduit 32 irradiates the primary X-rays generated by the X-ray generator 31 with a narrowed irradiation diameter to the powder contained in the powder sample cell 1 arranged at the irradiation position 2a. It is for irradiating the body sample P with primary X-rays, for example, from vertically above.

The detection section 4 includes, for example, a detector 41 and an output section for outputting a signal from the detector 41 to the information processing device 5 .
The detector 41 is, for example, a Silicon Drift Detector (SDD) or the like.
The output unit detects, for example, a charge corresponding to the magnitude of energy generated by the incidence of fluorescent X-rays generated from the powder sample P on the detector 41, and outputs the detected charge to the magnitude of the charge. Digital Pulse Processor (DPP) or the like that converts to a trapezoidal wave signal having a height corresponding to .

The information processing device 5 includes, for example, an irradiation control unit 51 that controls the X-ray irradiation mechanism 3 and an analysis unit 52 that performs X-ray analysis based on the output signal output from the detection unit 4. be.

The analysis unit 52 quantitatively analyzes the elements in the powder sample P, for example, based on the number of trapezoidal wave signal detections counted for each peak value output by the signal output unit of the detection unit 4. .

This information processing device 5 physically consists of a computer main body comprising a CPU, a memory, an A/D converter, a D/A converter, a communication port, etc., input means such as a keyboard and a mouse connected to the computer main body, and It consists of a display. By installing a predetermined program in the memory, the information processing device 5 functions as the irradiation control section 51 and the analysis section 52, as shown in FIG.

2 to 4, the powder sample cell 1 used in this embodiment includes, for example, a surrounding member 11 surrounding the powder sample P from the side and a It comprises an X-ray permeable film 12 and a support member 13 for supporting the X-ray permeable film 12 .

The surrounding member 11 is, for example, a flat plate having one or more through holes 111 . In this embodiment, as an example, as shown in FIGS. 2 to 4, one acrylic plate having a thickness of 2 mm and four cylindrical through-holes 111 having an inner diameter of 1.5 mm are used. ing. The material of the surrounding member 11 has a desired strength, transmits X-rays with little scattering, and does not contain the element to be analyzed contained in the powder sample P. is preferred.

The X-ray transmissive film 12 is, for example, a film having a predetermined X-ray transmittance, and is preferably made of a material capable of suppressing X-ray scattering caused by the X-ray transmissive film 12 as much as possible. Specifically, the X-ray permeable film 12 contains one or more resins selected from the group consisting of polyethylene, polypropylene, polyethylene terephthalate, and the like. In this embodiment, a film made of polyethylene is used as an example of the X-ray transparent film 12 .
The thickness of the X-ray transparent film 12 is preferably 250 μm or less, more preferably 30 μm or less, because X-ray scattering caused by the X-ray transparent film 12 can be suppressed more effectively when the thickness is small.

The support member 13 has, for example, a hollow portion 131 formed in a flat plate made of the same material as the surrounding member 11 described above. In this embodiment, the hollow portion 131 is, for example, a hollow hole that vertically penetrates the support member and is larger than the through hole 111 formed in the surrounding member 11. is. In this embodiment, as with the surrounding member 11, an acrylic plate having a thickness of 4.0 mm and four cylindrical holes having an inner diameter of 10 mm are used. The hollow hole is formed so that the central position of the hollow hole formed in the supporting member 13 and the central position of the through hole 111 formed in the surrounding member 11 are aligned. By configuring in this way, for example, as shown in FIG. It is positioned. In this embodiment, the support member 13 is configured to sandwich and support the X-ray permeable film 12 with the surrounding member 11 .
The material of the support member 13 preferably has a desired strength and transmits X-rays with little scattering.

The inner peripheral surface of the through hole 111 formed in the surrounding member 11 and the upper surface of the X-ray transmissive film 12 form a sample containing space 1a for containing the sample.

Another feature of the X-ray fluorescence spectrometer according to this embodiment is that the sample chamber 2 includes an opening/closing door 21 for taking in and out the powder sample cell 1, and a powder sample inside the sample chamber 2. A movement mechanism 22 for moving the cell 1 is provided, and the fluorescent X-ray spectrometer 100 further includes a decompression mechanism 6 .

The opening/closing door 21 is, for example, an acrylic sliding door. The inside of the sample chamber 2 can be hermetically sealed by closing the opening/closing door 21 .

The moving mechanism 22 has, for example, a stage 221 and a motor 222 . More specifically, for example, the stage 221 is configured to move when the motor 222 rotates in response to an instruction from the movement control unit 53 provided in the information processing device 5 .

The powder sample cell 1 is installed on the stage 221, and the powder sample cell 1 moves as the stage 221 moves. Here, the moving direction is the horizontal direction, and the moving mechanism 22 moves the irradiation position 2a, which is the position of the powder sample cell 1 when irradiating the powder sample P with X-rays, and the opening/closing door 21. The powder sample cell 1 is horizontally moved between an installation position 2b, which is a position where the powder sample cell 1 is installed, and which is set below. In this embodiment, the irradiation position 2a and the installation position 2b are set at different positions in the sample chamber 2, respectively.

The decompression mechanism 6 includes, for example, an exhaust port 61 formed in the wall of the sample chamber 2 , a vacuum pump connected to the exhaust port 61 for decompressing the inside of the sample chamber 2 , and the exhaust port 61 . It is provided with a valve or the like disposed between the vacuum pump and releasing the decompressed state in the sample chamber 2 by opening the inside of the sample chamber 2 to the atmosphere.

In this embodiment, the exhaust port 61 is arranged such that the distance between the installation position 2b and the exhaust port 61 is greater than the distance between the irradiation position 2a and the exhaust port 61. It is

Using the powder sample cell 1 and the fluorescent X-ray analyzer configured as described above, the method and procedure for performing the fluorescent X-ray analysis of the powder sample P will be described below with reference to FIG. In this embodiment, an X-ray analysis microscope (XGT-7200) manufactured by Horiba, Ltd. is used as an example of the X-ray fluorescence analyzer.

First, a powder sample P is put into the sample storage space 1a of the powder sample cell 1 (S1). At this time, after putting the powder sample P into the sample storage space 1a of the powder sample cell 1 so that the powder sample P has a uniform thickness in the sample storage space 1a, the powder sample P is vibrated or moved upward. It is also possible to press the mixture evenly with a stick or the like so that there is no gap. For example, when using a powder sample cell 1 as shown in FIG. 2, one powder sample cell 1 has a plurality of sample storage spaces 1a. may contain powder samples P of different types.

After the powder sample P is accommodated in the powder sample cell 1 in this way, the powder sample cell 1 is installed at the installation position 2b in the sample chamber 2 through the opening/closing door 21 of the sample chamber 2 (S2).

With the powder sample cell 1 placed at the installation position 2b and the opening/closing door 21 closed as described above, the pressure in the sample chamber 2 is reduced by the pressure reducing mechanism 6 (S3).
Specifically, with the inside of the sample chamber 2 connected to the vacuum pump through the exhaust port 61 , the vacuum pump is operated to gently remove the air in the sample chamber 2 to the outside of the sample chamber 2 . Evacuate to vacuum.

After confirming that the pressure in the sample chamber 2 has been reduced to a predetermined pressure, the movement control unit 53 controls the movement mechanism 22 to move the powder sample cell 1 from the installation position 2b. It is moved to the irradiation position 2a (S4).

Next, the irradiation control unit 51 causes the X-ray irradiation mechanism 3 to irradiate the powder sample P accommodated in the powder sample cell 1 with X-rays from the X-ray irradiation mechanism 3 . Fluorescent X-rays generated when the irradiated X-rays strike the powder sample P are detected by the detection unit 4 by scanning the sample (S5). At this time, the primary X-rays transmitted through the powder sample P may be received by, for example, a transmitted X-ray receiving section 42 provided in the detection section 4 or the like.
An example of X-ray irradiation and detection conditions is as follows: X-ray tube voltage: 30 kV, tube current: 1.0 mA, irradiation diameter: 100 μm, X-ray working distance: 1 mm, scan range: 0.512 mm square, analysis time: may be set to 1000 seconds. Since it is preferable to scan only the portion of the powder sample P, the scanning range can be appropriately changed according to the inner diameter of the through hole. It goes without saying that other conditions may be changed as appropriate according to the analysis target.

The analysis unit 52 quantitatively analyzes the components of the powder sample P based on the intensity of the fluorescent X-rays detected by the detection unit 4 (S6). In this embodiment, the analysis unit 52 quantitatively analyzes the components of the powder sample P by FPM (Fundamental parameter method). For example, a geochemical reference material or the like is used as a standard sample, calibration is performed using the integrated spectrum of this standard material, and then quantitative analysis of the powder sample P to be measured is performed.

When the analysis is completed, the powder sample cell 1 is returned from the irradiation position 2a to the installation position 2b by the moving mechanism 22 (S7). After that, the sample chamber 2 is released to the atmosphere by the valve or the like provided in the decompression mechanism 6, and the decompression state is released (S8). Next, the analysis is completed by taking out the powder sample cell 1 from the opening/closing door 21 (S9).

According to the powder sample cell 1 and the fluorescent X-ray analyzer configured as described above, the following effects can be obtained.

Even without adding an additive such as a binder to the powder sample P, just by inserting the powder sample P into the through-hole 111 of the acrylic plate, it is held by the inner peripheral surface of the through-hole 111 and the film, and the density is uniform. A certain amount of thickness can be secured. Therefore, the accuracy of quantitative analysis using fluorescent X-rays is improved.

In the powder sample cell 1, the upper surface of the sample storage space 1a is open, and no film or the like for fixing the powder sample P is pasted thereon.
If a film or the like is attached to the upper surface of the conventional powder sample cell, the fluorescent X-rays emitted upward from the powder sample P inserted into the sample storage space 1a will be absorbed. , the detection intensity of fluorescent X-rays deteriorates, and the measurement accuracy drops. In particular, when the powder sample P is trace powder such as precious sand, rock, mineral, pharmaceutical, etc., it often contains light elements such as Na and Mg as main components and trace components. Fluorescent X-rays with short wavelengths generated from light elements such as Na and Mg are easily absorbed by the film, so if the upper surface of the sample storage space 1a is covered with the film, the detection intensity will drop significantly.
On the other hand, according to the powder sample cell 1 according to the present embodiment, the fluorescent light emitted upward from the powder sample P is not attached to the upper surface of the sample storage space 1a by covering the upper surface of the sample storage space 1a. Since the X-rays reach the detector 41 without being absorbed, it is possible to accurately measure elements with wavelengths that are easily absorbed. In addition, when the amount of the powder sample P is very small, the intensity of the generated fluorescent X-rays is weak, so that the absorption of the fluorescent X-rays by the film or the like causes a marked deterioration in measurement accuracy. Fluorescent X-rays generated upward from the powder sample P reach the detector 41 without being absorbed by a film or the like, so that even a very small amount of the powder sample P can be quantitatively analyzed with high accuracy. can.

Furthermore, since the bottom surface of the sample storage space 1a is formed of the X-ray transmissive film 12, scattering of X-rays by the bottom surface of the sample storage space 1a can be suppressed. As a result, background noise in fluorescent X-ray analysis can be reduced.

The support member 13 is provided, and the center position of the hollow hole formed in the support member 13 and the center position of the through hole 111 formed in the surrounding member 11 are made to coincide. Therefore, a hollow portion 131 is formed under the sample housing space 1a, and a member that reflects X-rays does not come into direct contact with the bottom of the X-ray transmissive film 12. As shown in FIG. As a result, background noise in fluorescent X-ray analysis can be reduced more reliably. In addition, since the hollow portion 131 is a hollow hole vertically penetrating the support member, scattering of X-rays by the bottom surface of the hollow portion 131 can also be suppressed.

Since the hollow hole formed in the supporting member 13 is formed to be larger than the through hole 111 formed in the surrounding member 11, even if the supporting member 13 is arranged with a slight deviation, the sample accommodating space is maintained. The cavity 131 can be more reliably positioned under 1a.
Furthermore, since the hollow hole is formed to be larger than the through hole 111 formed in the surrounding member 11, the powder sample P accommodated in the sample accommodation space 1a reflects the light toward the support member 13. Therefore, it is possible to prevent the X-rays from hitting the supporting member 13 directly below the sample accommodating space 1a. As a result, noise in fluorescent X-ray analysis due to reflection and scattering of X-rays by the support member can be reduced.

Since the powder sample cell 1 is formed with four sample storage spaces 1a, each of the four sample storage spaces 1a can store powder samples P of different types. Since the position of each of the four sample storage spaces 1a in the powder sample cell 1 can be easily identified, a plurality of types of powder samples P can be analyzed in one analysis operation. .

Since the decompression mechanism 6 is provided, the inside of the sample chamber 2 can be decompressed, for example, into a vacuum state. When the sample P is to be analyzed, the absorption of X-rays by air can be suppressed, and the accuracy of analysis can be further improved.

The exhaust port 61 is arranged such that the distance between the installation position 2b and the exhaust port 61 is larger than the distance between the irradiation position 2a and the exhaust port 61. , the powder sample held in the powder sample cell 1 by the air flow in the sample chamber 2 when the sample chamber 2 is decompressed or the decompressed state in the sample chamber 2 is released. It is possible to suppress the scattering of P as much as possible.

In addition, the present invention is not limited to the above embodiments.
For example, the surrounding member is not limited to one having four through-holes formed in a single flat plate acrylic plate as described above, and for example, a plurality of cylindrical members as shown in FIGS. It may be a cylindrical body of The number of through-holes and cylindrical bodies provided in one powder sample cell may be one or any number of two or more, and is not limited. When a plurality of through-holes or cylindrical bodies are provided, if the distance between the plurality of through-holes or cylindrical bodies is set to be larger than the irradiation width of the X-rays guided by the X-ray tube, each X-rays can be irradiated while distinguishing between the through-hole and the sample containing space corresponding to the cylindrical body.
The shape of the sample housing space is not limited to the cylindrical shape described above, and may be a prismatic shape, a deformed cylindrical shape, or the like.

The support member is not limited to the one described above. For example, as shown in FIGS. It is good also as something like a frame provided with one or more. When a support member having such a shape is used, the X-ray permeable film may be supported by being sandwiched between the surrounding member and the support member, or the X-ray permeable film may be placed only on the support member. A cylindrical surrounding member as described above may be fixed on the X-ray permeable film stretched by fixing the X-ray transparent film.

The cavity formed in the support member does not necessarily have to penetrate the support member, and has a bottom as long as X-ray scattering by the bottom surface of the cavity does not become background noise in fluorescent X-ray analysis. It is good also as a crevice of. The shape of the hollow portion is not limited to the cylindrical shape described above, and may be a prismatic shape, an irregular cylindrical shape, or the like.

The inner diameter and height of the through-hole 111 or the cylindrical body are not limited to those described above, and may be appropriately changed depending on the amount of the powder sample P to be analyzed. The inner diameter of the through-hole 111 and the cylindrical body is preferably 0.5 mm or more and 5 mm or less. In some cases, the inner diameter may be 4 mm or the like.
Similarly, the through-hole 111 or the height of the cylindrical body may be appropriately changed depending on the amount of the powder sample P to be analyzed. The height of the through hole 111 or the cylindrical body is preferably 0.1 mm or more and 4 mm or less. , and if the weight is 100 mg, the height may be set to 3 mm or the like.
In addition, the ratio of the inner diameter to the height described above may be changed as appropriate depending on the amount of the powder sample P to be analyzed. ) is preferably in the range of 0.75 to 2.

As an actual experimental example using the powder sample cell and the fluorescent X-ray analyzer according to the present invention, a plurality of types of geochemical reference materials were used as the powder sample P under the conditions described above. The amount of the body sample P was changed to 1 mg, 10 mg, and 100 mg, and the average and standard deviation of the quantitative values of each constituent element were determined when each measurement was repeated five times. As a result, even when 1 mg of powder sample P was used, the certified amount of each element in each geochemical reference material and the calculated quantitative value of each element were in very good agreement. It has been confirmed that the standard deviation does not change much compared to the case of using body samples.

The support member may be made of the same material as the surrounding member, or may be made of a different material.

Although it is preferable that the fluorescent X-ray spectrometer includes the moving mechanism and the pressure reducing mechanism, these are not essential constituent elements.

The powder sample may be filled up to the upper surface of the sample-accommodating space, but it is not necessary to fill the sample-accommodating space up to the upper surface. It is sufficient to put the powder sample in such an amount that it can be filled. When quantitative analysis is performed using FPM as in the above-described embodiment, the upper surface of the surrounding member and the upper surface of the sample-accommodating space are arranged so as to form the same plane in order to further improve analysis accuracy. Preferably, the powder sample is packed up to the upper surface of the sample-accommodating space. In particular, when a soil sample such as sand or rock is to be analyzed, the powder sample often contains many elements such as carbon and hydrogen that do not affect fluorescent X-ray analysis. Therefore, when a soil sample is to be analyzed, for example, by using a material containing a large amount of elements such as carbon and hydrogen that do not affect fluorescent X-ray analysis for the surrounding member, the sample It is preferable to match the density of the powder sample in the housing space with the density of the surrounding member.
In addition, various modifications and combinations of embodiments may be made without departing from the gist of the present invention.

DESCRIPTION OF SYMBOLS 100... X-ray fluorescence analyzer 1... Powder sample cell 11... Surrounding member 111... Through hole 12... X-ray permeable membrane 13... Supporting member 131... Cavity part 1a . Apparatus 2 ... Sample chamber 6 ... Decompression mechanism 61 ... Exhaust port

Claims (9)

It is used for fluorescent X-ray analysis for irradiating a powder sample with primary X-rays from above and detecting fluorescent X-rays emitted upward from the powder sample,
a surrounding member having an upper surface and a lower surface, and having a through hole formed at a predetermined location for communicating between the upper surface and the lower surface;
and an X-ray transparent film attached to the lower surface of the surrounding member,
A sample housing space is formed by the inner peripheral surface of the through-hole and the X-ray transmissive film, and only the upper surface is open ;
a support member that sandwiches and supports the X-ray transparent film between itself and the lower surface of the surrounding member;
The powder sample cell, wherein the support member is provided with a hollow portion whose upper surface is open at least, and the through hole is positioned inside the hollow portion when viewed from a direction perpendicular to the X-ray transparent film. . 2. A powder sample cell according to claim 1, wherein said X-ray transparent film contains a resin. 3. The powder sample cell according to claim 1, wherein said surrounding member is a flat plate having one or more through-holes. 2. The powder sample cell according to claim 1 , wherein the supporting member is a flat plate-like member having one or more holes through which the hollow portion extends vertically. It is used for fluorescent X-ray analysis for irradiating a powder sample with primary X-rays from above and detecting fluorescent X-rays emitted upward from the powder sample,
a surrounding member having an upper surface and a lower surface, and having a through hole formed at a predetermined location for communicating between the upper surface and the lower surface;
and an X-ray transparent film attached to the lower surface of the surrounding member,
a powder sample cell in which a sample storage space whose top surface is open is formed by the inner peripheral surface of the through hole and the X-ray transparent film;
an X-ray irradiation mechanism for irradiating the powder sample with primary X-rays;
a detection unit for detecting fluorescent X-rays generated when the powder sample is irradiated with primary X-rays ,
A fluorescent X-ray spectrometer , wherein the X-ray irradiation mechanism narrows down the irradiation diameter of the primary X-rays . 6. The fluorescent X-ray spectrometer according to claim 5 , comprising a sample chamber for accommodating said powder sample cell, and a decompression mechanism for depressurizing said sample chamber. As positions of the powder sample cell in the sample chamber, an irradiation position, which is a position at which the powder sample inserted into the powder sample cell is irradiated with primary X-rays from the irradiation mechanism, and the irradiation position. is provided separately and an installation position, which is a position where the powder sample cell is placed before irradiation, is set,
further comprising a moving mechanism for moving the powder sample cell between the irradiation position and the installation position;
The decompression mechanism has an exhaust port formed on the wall of the sample chamber for exhausting air from the sample chamber, and the distance between the installation position and the exhaust port is greater than the distance between the irradiation position and the exhaust port. 7. The fluorescent X-ray spectrometer according to claim 6 . A fluorescent X-ray analysis method, comprising using the powder sample cell according to any one of claims 1 to 4 . a surrounding member having an upper surface and a lower surface, and having a through hole formed at a predetermined location for communicating between the upper surface and the lower surface;
and an X-ray transparent film attached to the lower surface of the surrounding member,
A fluorescent X-ray analysis method using a powder sample cell, characterized in that the inner peripheral surface of the through-hole and the X-ray transparent film form a sample housing space whose upper surface is open,
inserting a powder sample into the powder sample cell;
A fluorescent X-ray analysis method characterized by irradiating a powder sample with focused primary X-rays from above, and detecting fluorescent X-rays emitted upward from the powder sample.

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