WO2004088296A1

WO2004088296A1 - Fluorescent x-ray analyzer

Info

Publication number: WO2004088296A1
Application number: PCT/JP2004/003229
Authority: WO
Inventors: Yasuhiro Ayukawa; Megumi Ono; Yukio Sako
Original assignee: Rigaku Industrial Corporation
Priority date: 2003-03-28
Filing date: 2004-03-11
Publication date: 2004-10-14
Also published as: CN100464182C; CN1739022A; JPWO2004088296A1; JP3726161B2

Abstract

A fluorescent X-ray analyzer adapted for helium replacement, which is easy to replace a partition film between a sample chamber and an irradiation chamber, and prevents air in the sample chamber from flowing into the irradiation chamber during analysis. A first frame body (21) is hermetically attached to a wall (4) so that its window (21a) lies over the window (4a) of the wall (4) between a sample chamber (3) and an irradiation chamber (8), with a partition film (9) disposed to cover the window (21a) of the first frame body. A second frame body (23) is disposed so that its window (23a) lies over the window (21a) of the first frame body with a partition film (9) held therebetween. And one the frame bodies (21, 23) is a permanent magnet, and the other is made of a material which can be attracted thereby. The frame bodies (21, 23) hold the periphery of the partition film (9) therebetween, and the second frame body (23) is removably attachable to the first frame body (21).

Description

X-ray fluorescence analyzer

Technical field

The present invention relates to an X-ray fluorescence spectrometer that performs analysis in a helium atmosphere. Background art

Conventionally, there is a fluorescent X-ray analyzer that performs analysis in a helium atmosphere (the X-ray optical path is in a helium atmosphere) as shown in Fig. 2. This device is a bottom-illuminated type in which primary X-rays 6 are irradiated from below sample 1, and an X-ray source 7 is stored below sample room 3 in which sample 1 is exchangeably stored in the atmosphere. An irradiation chamber 8 is provided, and a spectroscopic chamber 14 in which the light separating element 11 and the detector 13 are housed in communication with the irradiation chamber 8 is provided. Since the irradiation chamber 8 and the spectroscopic chamber 14 are replaced with helium, the absorption of the fluorescent X-rays 10 and 12 is smaller than that in the air atmosphere, and the fluorescent X-rays 10 and Weak detection even with weak X-ray fluorescence. Here, a partition wall film 9 that allows X-rays 6 and 10 to pass through is provided in a window 4 provided in a wall section 4 that separates a sample chamber 3 in an air atmosphere and an irradiation chamber 8 in a helium atmosphere (hereinafter, window means an opening). However, in this case, it means a hole formed in the wall 4). As the partition film 9, a thin polymer film such as a polyimide film is used so that absorption of X-rays 6 and 10 is small. A liquid sample la is analyzed in a helium atmosphere. In this case, the liquid sample 1a is supplied to the liquid sample holder 2 having a window member 2a at the bottom through which X-rays 6 and 10 pass. The sample is put into a sample 1 in the whole 1a, 2 and placed on the partition film 9 in the sample room 3 in the atmosphere. The liquid sample 1a leaking to the outside of the window member 2a of the liquid sample holder 2 and the contaminants in the air may adhere to the partition wall film 9, and in this case, the partition wall film 9 is thin and easily broken. It is not really possible to clean the parts without damaging them, so they need to be replaced.

As a first conventional X-ray fluorescence analyzer corresponding to the exchange of the partition membrane, there is one described in JP-A-2003-254919. In this device, the partition wall film is handled by being attached to a ring-shaped support plate, and further, the peripheral portion is sandwiched in the thickness direction by the upper portion and the lower portion of the ring-shaped holder, so that the whole is a partition wall film cartridge. Upper part of holder And the lower part of the holder are connected by screws or the like. Therefore, it is necessary to prepare a new partition membrane by attaching it to the support plate in advance for the replacement of the partition membrane. At the time of replacement, remove the entire partition membrane cartridge from the device, remove the screws, disconnect the connection between the upper and lower holders, replace the partition membrane with a new one for the support plate, and screw down. Then, the obtained partition membrane cartridge is sandwiched between the upper and lower holders, and the resulting partition membrane cartridge is mounted on the apparatus. The partition membrane force cartridge is mounted so as to cover the window provided on the wall section separating the sample chamber and the irradiation chamber. At this time, the space between the partition membrane cartridge (the lower part of the holder) and the wall section is provided. Sealed with 〇 ring.

As a second conventional fluorescent X-ray analyzer corresponding to the replacement of the partition membrane, there is one described in Japanese Patent No. 2943033. In this apparatus, the X-ray permeable sheet corresponding to the partition wall film is sandwiched between the outer frame and the inner frame formed in the annular body, and the whole becomes a sample cell table. Since it is simply fitted into the frame, it is removable. In addition, the entire sample cell table is simply placed on the measurement site of the bench on which it is to be placed, so it is removable.

In the first conventional X-ray fluorescence spectrometer, since the structure of the partition membrane force cartridge including the partition membrane is complicated and difficult to disassemble, it is not easy to replace the partition membrane. On the other hand, in the second conventional X-ray fluorescence spectrometer, the sample cell table including the partition wall is detachable from the measurement site of the bench, and the sample cell table itself can be easily assembled and disassembled. Therefore, it is easy to exchange the partition film. However, it is not assumed that the irradiation room and the spectroscopy room will be replaced by a space, and the entire sample cell table is simply placed on the measurement site of the bench, and there is no particular seal between the two. If this is done, the air in the sample chamber may flow into the irradiation chamber and the spectroscopic chamber during analysis, and X-ray absorption may increase. Disclosure of the invention

The present invention has been made in view of the above-mentioned conventional problems, and in a fluorescent X-ray analyzer that performs analysis in a helicopter atmosphere, a diaphragm for separating a sample chamber and an irradiation chamber and allowing X-rays to pass therethrough is easily replaced. Air in the sample chamber flows to the irradiation chamber and the spectroscopy chamber during analysis. The purpose is to provide something that is unlikely to enter.

In order to achieve the above object, the present invention provides a sample chamber in which a sample is exchangeably stored in an air atmosphere, an irradiation chamber in which an X-ray source for irradiating a sample with primary X-rays is stored. It houses a partition wall film that is arranged so as to cover the window provided on the wall that separates the sample chamber and the irradiation chamber and allows X-rays to pass through, and a detection means for spectrally detecting and detecting fluorescent X-rays generated from the sample. An X-ray fluorescence spectrometer, comprising: a spectroscopic chamber communicating with the irradiation chamber, wherein the irradiation chamber and the spectroscopic chamber are replaced by a helm.

A first frame having a window is hermetically attached to the wall so that the window overlaps the window of the wall, and covers the window of the first frame overlapping the window of the wall. The partition film is arranged as described above, and the second frame having a window is arranged such that the window overlaps the window of the first frame with the partition film interposed therebetween. Further, one of the first frame and the second frame is made of a permanent magnet, and the other is made of a material that is attracted to the permanent magnet, so that the first frame and the second frame are The peripheral portion of the partition wall film is sandwiched in the thickness direction, and the second frame is detachable from the first frame hermetically attached to the wall.

In the X-ray fluorescence spectrometer according to the present invention, the partition wall film is sandwiched between the first frame and the second frame, but the first frame is airtight to the wall separating the sample chamber and the irradiation chamber. Since the second frame is detachable from the first frame, the partition membrane can be easily replaced, and the air in the sample chamber is transferred to the irradiation chamber and the spectroscopic chamber during analysis. There is no danger of inflow. Here, it is preferable that the first frame and the second frame are plate-shaped, one of which is made of a magnet sheet, and the other is made of iron. Further, it is preferable that the partition film is made of polyester. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is an enlarged view of the vicinity of a partition film in an X-ray fluorescence spectrometer according to one embodiment of the present invention.

FIG. 2 is a schematic diagram showing an X-ray fluorescence spectrometer that performs analysis in a helium atmosphere. BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, a configuration of the X-ray fluorescence analyzer according to one embodiment of the present invention will be described. First, as shown in Fig. 2, this device is a bottom-illuminated type in which primary X-rays 6 are irradiated from below the sample 1, as in the device described in the prior art. 8. An X-ray fluorescence spectrometer comprising a partition film 9 and a spectroscopic chamber 14, wherein the irradiation chamber 8 and the spectroscopic chamber 14 are replaced with helium. The sample chamber 3 is formed of a space surrounded by a wall 4 that separates the sample chamber 3 from the irradiation chamber 8 and a lid 5 that is openably and closably mounted on the upper part of the sample chamber 3 via a seal member. Sample 1 is exchangeably stored. The irradiation chamber 8 accommodates an X-ray source 7 such as an X-ray tube for irradiating the sample 1 with primary X-rays 6. Here, the partition wall film 9 is a polyester film having a thickness of 1.5 m. The partition wall film 9 is arranged so as to cover the circular window 4 a provided on the wall portion 4 and allows the X-rays 6 and 10 to pass therethrough. The spectroscopic chamber 14 communicates with the irradiation chamber 8 and includes a spectroscopic element 11 for separating the fluorescent X-rays 10 generated from the sample 1 and a detector 13 for detecting the separated fluorescent X-rays 12. Detection means 11 and 13 are stored. The spectroscopic element 11 and the detector 13 are rotated while maintaining a fixed angular relationship by an interlocking means such as a goniometer (not shown).

Here, as described above, the analysis target is, for example, a liquid sample 1a, and the liquid sample 1a is a liquid sample holder 2 having a window member 2a at the bottom portion through which X-rays 6 and 10 pass. The sample is put in the whole la, 2 and is displayed as a sample 1, and is placed on the partition film 9 in the sample chamber 3 in the atmosphere. The liquid sample holder 2 has a cylindrical main body 2b, two window members 2a arranged to cover the upper and lower openings thereof, and a window member 2a which is fitted into the upper and lower outer peripheries of the main body 2b, respectively. It is composed of two ring-shaped mounting members 2c that sandwich the peripheral portion.

As shown in FIG. 1 which is an enlarged view, the first frame 21 having a circular window 21 a and a first frame 21 having a circular window 21 a is configured as shown in FIG. 1 which is an enlarged view. Is air-tightly attached to the wall portion 4 by, for example, bonding so as to overlap the circular window 4a of the wall portion 4 (so that the openings are connected in the vertical direction). Then, a partition wall film 9 is arranged so as to cover the window 21 a of the first frame body 21, and further, a second plate having a circular shape having a thickness of 0.5 mm and having a circular window 23 a is provided. The second frame 23 is arranged such that the window 23 a overlaps the circular window 21 a of the first frame 21 with the partition wall 9 interposed therebetween. First frame 2 The outer diameters of the first and second frame members 23 are the same, and each of the windows 21a and 23a is the same circle as the outer circumference.

Here, the first frame 21 is made of a permanent magnet, for example, a magnet sheet (a permanent magnet made by dispersing a magnetic material in a flexible sheet of rubber or synthetic resin), and the second frame 23 is made of a permanent magnet. Since the first frame 21 and the second frame 23 are made of a material adsorbed to the permanent magnet, for example, iron, the first frame 21 and the second frame 23 sandwich the peripheral portion of the partition wall film 9 in the thickness direction thereof and the second frame. The body 23 is detachable from the first frame 21 airtightly attached to the wall 4. Conversely, the second frame 23 may be made of a permanent magnet, and the first frame may be made of a material that is attracted to the permanent magnet. Note that in FIGS. 1 and 2, the lines visible behind the paper are not shown for ease of understanding.

In this apparatus, as shown in FIG. 2, the following pipes, valves and pumps are provided to replace the irradiation chamber 8 and the spectroscopic chamber 14 with helium. Helium is introduced from the helium tank (not shown) to the irradiation chamber 8 and the spectroscopic chamber 14 through the helium flow valve 16 A through the helium flow valve 16 A. The vacuum pipe 17B is evacuated to the irradiation chamber 8 and the spectroscopic chamber 14 by the vacuum pump 17 through the vacuum valve 16B. The spectroscopic chamber leak pipe 15 C opens the irradiation chamber 8 and the spectroscopic chamber 14 to the atmosphere via the spectroscopic chamber leak valve 16 C. The sample chamber leak pipe 15D opens the sample chamber 3 to the atmosphere via the sample chamber leak valve 16D. The bypass pipe 15E connects the spectroscopic chamber leak pipe 15C and the sample chamber leak pipe 15D via a bypass valve 16E.

Next, the operation of this device will be described. First, in Fig. 2, before placing sample 1 in sample chamber 3, the helium flow valve 16A, the spectroscopic chamber leak valve 16C and the sample chamber leak valve 16D are closed, and the vacuum valve 16B and Open the bypass valve 16 E and evacuate the irradiation chamber 8, the spectroscopic chamber 14 and the sample chamber 3 by the vacuum pump 17. When the specified degree of vacuum is reached, the vacuum valve 16 B is closed, the vacuum pump 17 is stopped, the helium flow valve 16 A is opened, and the irradiation chamber 8 and the spectroscopic chamber 14 and the sample chamber 3 are opened. Introduce a helm to Then, the bypass valve 16E is closed, and the spectroscopic chamber leak valve 16C is opened, and helium flows into the irradiation chamber 8 and the spectroscopic chamber 14 at a low flow rate. With this, the helium substitution in the irradiation chamber 8 and the spectroscopic chamber 14 was Complete. In addition, the sample chamber 3 is also evacuated or helium is introduced in order to prevent the partition wall film 9 from being damaged by a pressure difference between the sample chamber 3 and the irradiation chamber 8 and the spectroscopic chamber 14. It is.

On the other hand, by opening the sample chamber leak valve 16 D and opening the lid 5, the sample chamber 3 can exchange the sample 1 in the air atmosphere. Specifically, it is placed on the second frame 23 (FIG. 1), and the lid 5 is closed. Thereafter, the sample chamber 3 is maintained in the atmosphere, and the irradiation chamber 8 and the spectroscopy chamber 14 are maintained in a helium atmosphere with a slightly higher pressure. Can be exchanged for analysis.

In order to quickly complete the helium replacement in the irradiation chamber 8 and the spectroscopic chamber 14, vacuum was drawn.However, without vacuuming, a large amount of helium was flowed at a high flow rate to expel air, and then a low flow rate was obtained. Helium replacement may be carried out by flowing in In this case, it takes time for the helium substitution to be completed (the displacement of air reaches the limit and the absorption of X-rays stabilizes), but without evacuating the irradiation chamber 8 and the spectroscopic chamber 14, Therefore, the procedure is simple because the evacuation of the sample chamber 3 and the replacement of helium are not required.

If the partition wall membrane 9 is contaminated for the reasons described above and needs to be replaced, stop the device, stop the flow of helium, open the lid 5 and remove the sample 1 from the device. The second frame 23 of 1 is taken out of the device against the suction force from the first frame 21. If the contaminated partition film 9 comes under the second frame 23, peel off the partition film 9 and remove it if it remains on the first frame 21. Peel off membrane 9 and remove from device.

Then, for example, an end portion is cut out into a substantially square shape from a polyester film having a width larger than the outer diameter of the first and second frames 21 and 23 to form a new partition wall film 9. Place so as to cover 1 frame 2 1. Further, the second frame 23 is placed thereon so that the outer periphery of the second frame 23 is aligned with the outer periphery of the first frame 21, and the partition wall film 9 is held by the attraction force from the first frame 21. . When the sandwiched partition wall film 9 is wrinkled, the peripheral portion of the partition wall film 9 that protrudes outside the first and second frames 21 and 23 is pulled and extended. Now that the replacement of the partition film 9 has been completed, the helium substitution described above is performed, and the test is performed. The analysis can be continued with room 3 as the air atmosphere.

As described above, in the X-ray fluorescence spectrometer of the present embodiment, the partition film 9 is sandwiched between the first frame 21 and the second frame 23, but the first frame 21 is the sample. Since the second frame 23 is detachably attached to the first frame 21 and the second frame 23 is mounted airtightly on the wall 4 separating the chamber 3 and the irradiation chamber 8, the partition wall film 9 can be easily replaced. In addition, there is no possibility that the air in the sample chamber 3 flows into the irradiation chamber 8 and the spectroscopic chamber 14 (FIG. 2) during the analysis. Also, the first frame 21 and the second frame 23 are plate-shaped, one of which is a magnet seater, and the other is made of iron, so that it can be configured simply and inexpensively. Here, between the sample 1 and the partition wall film 9, that is, between the lower window member 2a and the partition wall film 9, the liquid sample 1a leaked to the outside of the window member 2a is formed on the partition wall film 9. A certain amount of space is required so that adhesion and contamination are small. On the other hand, since this space is a part of the sample chamber 3 in the atmosphere, it is usually filled with air, and absorbs and attenuates the fluorescent X-rays 10 (FIG. 2) generated from the sample 1, so from this viewpoint, Thinner is better. Considering the overall consideration, the thickness of this space should be adjusted to about 0.5 mm, but in this embodiment, since this space is the window 23 a of the second frame 23, The thickness of the plate-shaped second frame 23 can be adjusted easily and accurately.

Further, in the present embodiment, an inexpensive polyester film can be used for the partition wall film 9. In the past, expensive polyimide films resistant to X-ray exposure were often used, but in practice, they had to be replaced due to contamination before the end of their life. Therefore, if the partition film 9 can be easily replaced as in the present embodiment, it is more reasonable to use a material that is not so strong against X-ray exposure but is inexpensive, for example, a polyester film for the partition film 9. And preferred.

In the above embodiment, the wavelength dispersive X-ray fluorescence analyzer in which the detecting means 11 and 13 in FIG. 2 are composed of the spectroscopic element 11 and the detector 13 is taken as an example. The present invention can be similarly applied to an energy dispersive X-ray fluorescence spectrometer in which the detecting means is constituted by a detector such as an SSD and does not include a spectroscopic element.

Claims

The scope of the claims

1. A sample chamber in which samples are exchangeably stored in the atmosphere

An irradiation chamber for accommodating an X-ray source for irradiating the sample with primary X-rays,

A partition wall film that is arranged so as to cover a window provided in a wall part that separates the sample chamber and the irradiation chamber and that allows X-rays to pass therethrough;

A detection unit for spectrally detecting and detecting fluorescent X-rays generated from the sample, and comprising a spectroscopic chamber communicating with the irradiation chamber;

In the fluorescent X-ray analyzer in which the irradiation room and the spectroscopic room are replaced by a helm, a first frame having a window is hermetically attached to a wall so that the window overlaps a window of the wall,

The partition film is arranged so as to cover a window of a first frame body overlapping a window of the wall portion, and a second frame body having a window is provided in the first frame with the window sandwiching the partition film. It is placed so that it overlaps the body window,

One of the first frame and the second frame is made of a permanent magnet, and the other is made of a material that is attracted to the permanent magnet, so that the first frame and the second frame are A fluorescent material, which sandwiches a peripheral portion of the partition wall film in a thickness direction thereof, and wherein the second frame is detachably attached to a first frame hermetically attached to the wall. X-ray analyzer.

2. In Claim 1,

An X-ray fluorescence spectrometer wherein the first frame and the second frame are plate-like, one of which is made of a magnet sheet, and the other is made of iron.

3. In claim 1,

An X-ray fluorescence analyzer in which the partition wall film is made of polyester.