JP2023074582A - Isotope extraction device - Google Patents

Abstract

To provide an isotope extraction device which can heat a sample such as quartz up to a temperature that enables phase transition in a short time.SOLUTION: An isotope extraction device 100a comprises: a heating furnace 10 which performs heating for extracting a carbon isotope from a sample M of quartz; and a reaction cell 90 which has such a structure that a pair of test tube-like tubes 91, 92 is vertically overlapped with each other, and holds the sample M in an internal space IS. The reaction cell 90 enables extraction gas generated in the reaction cell 90 during the reaction of the sample M to be held while avoiding the contamination of the atmospheric air and the extraction gas to be recovered by utilizing a gas recovery part 21a of a separation processing device 21 after the reaction. The heating furnace 10 comprises: a plurality of light heating devices 13 which are provided around the outer side of the reaction cell 90 and collect light for the sample M; and an interior heating device 14 provided on the inner side of the reaction cell 90.SELECTED DRAWING: Figure 1

Description

The present invention relates to an isotope extraction apparatus for releasing gaseous target substances from rocks, and more particularly to an isotope extraction apparatus suitable for extracting gasified radiocarbon from quartz by heating the quartz.

Surface radiation dating methods using radionuclides produced in the Earth's surface by cosmic ray irradiation have been developed to allow estimation of surface exposure ages or erosion rates. In particular, the surface irradiation dating method using quartz can cover a wide range of ages due to the simple composition of quartz, chemical and physical stability, and multiple cosmic ray origin nuclides ¹⁰ Be, ²⁶ Al, and ¹⁴ C. Therefore, it is expected to be promising and is being put to practical use.

For example, a high-temperature furnace is used to extract ¹⁴ C from quartz as CO, etc., followed by oxidation of the CO to _CO2 , followed by purification of the _CO2 , and from the resulting _CO2 the abundance of the target nuclide ¹⁴ C is known (Non-Patent Documents 1 and 2). This technique is advantageous in that the sample used for the abundance determination of ¹⁴ C can also be used for the subsequent analysis of other cosmic-ray origin nuclides ¹⁰ Be and ²⁶ Al. There is also a method of using LiBO ₂ to flux quartz by heating at a relatively low temperature (Non-Patent Documents 1 and 3), but the sample used for the quantification of ¹⁴ C is used for the analysis of other cosmic ray origin nuclides. can no longer be used.

When extracting ¹⁴ C from quartz as CO or the like, it is desirable to heat quartz to a temperature at which the quartz undergoes a phase transition in a short period of time.

N.A. Lifton, et al., Geochimica et Cosmochimica Acta, Vol.65, No.12 (2001), pp.1953-1969 Y. Yokoyama, et al., Nuclear Instruments and Methods in Physics Research B223-224 (2004) 253-258 N.A. Lifton, et al., Nuclear Instruments and Methods in Physics Research B361 (2015) 381-386

SUMMARY OF THE INVENTION It is an object of the present invention to provide an isotope extraction apparatus capable of heating a sample such as quartz to a temperature at which a phase transition occurs in a short period of time.

In order to achieve the above object, an isotope extraction apparatus according to the present invention has a structure in which a heating furnace for performing heating for extracting carbon isotopes from a quartz sample and a pair of test tube-like tubes are vertically stacked. and a reaction cell for holding the quartz sample in an internal space, the reaction cell holding the extraction gas generated in the reaction cell during the reaction of the quartz sample while avoiding atmospheric contamination, and separating the extraction gas after the reaction. The gas can be recovered by using the gas recovery part of the processing apparatus, and the heating furnace includes a plurality of light heating devices that are provided around the outer periphery of the reaction cell and heat the quartz sample by condensing light. and an internal heating device provided inside the cell.

In the above-described isotope extraction apparatus, the quartz sample can be efficiently heated in the reaction cell by the irradiation heating from the outside of the reaction cell by the light heating device and the heating from the inside by the internal heating device. As a result, the quartz sample can be heated to a temperature at which the quartz sample undergoes phase transition in a short period of time, and the occurrence of contamination can be prevented.

In a specific aspect of the present invention, in the above-described isotope extraction apparatus, the reaction cell is a double-structured quartz tube, the internal space of which is airtight in a closed state, and a cavity for holding the quartz sample. , a gas extraction part provided in the upper part of the cavity and connected to the outside to release gas generated from the quartz sample, and an access recess for inserting the internal heating device inside. In this case, the quartz sample held in the cavity can be efficiently heated, and the carbon isotope can be efficiently extracted while maintaining the vacuum state.

In still another aspect of the invention, the light heating device has a halogen lamp and a mirror. In this case, a predetermined region can be efficiently heated by irradiating and heating with a plurality of halogen lamps.

In yet another aspect of the invention, the internal heating device includes a tungsten heater. In this case, even a narrow space inside the reaction cell can be efficiently heated.

In yet another aspect of the invention, the gas extractor has a light-absorbing barrier zone. In this case, heat leakage from the reaction cell can be suppressed. As a result, the O-ring provided in the gas extractor for maintaining a high vacuum can be kept sound.

In yet another aspect of the invention, the gas extractor has a groove for an O-ring fitting for connection with an external device. In this case, a high vacuum can be maintained by attaching an O-ring to the groove to prevent leakage due to pressure and vacuum.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure explaining the outline|summary of the whole isotope extraction analysis apparatus containing a heating furnace. It is a partial cross-sectional plan view of a heating furnace. FIG. 4 is a side view for explaining the structure of the reaction cell; (A)-(C) illustrate the elements inserted into the access recess of the reaction cell. It is a flowchart explaining the outline|summary of the analysis method using an isotope extraction analyzer.

[Embodiment]
Hereinafter, an embodiment of an isotope extraction analysis device 100 including an isotope extraction device 100a according to the present invention will be described with reference to the drawings.

As shown in FIG. 1 , the isotope extraction analysis device 100 includes a heating furnace 10 , a separation processing device 21 , a nuclide measurement device 22 and a control device 30 . The isotope extraction analysis device 100 includes, as elements associated with the heating furnace 10, an external heating drive device 40, a radiation thermometer drive device 50, an internal heating drive device 60, a temperature detection circuit 70, an inert gas supply device 80, and the like. . In the isotope extraction analysis device 100, the heating furnace 10, the external heating driving device 40, the radiation thermometer driving device 50, the internal heating driving device 60, the temperature detection circuit 70, the inert gas supply device 80, the separation processing device 21, and The control device 30 constitutes an isotope extraction device 100a.

As shown in FIGS. 1 and 2, the heating furnace 10 includes a container 11, a lid block 12, a plurality of light heating devices 13, an internal heating device 14, and a radiation thermometer 15. FIG. The heating furnace 10 is supported by a frame 16 in the air. A reaction cell 90 can be detachably attached to the heating furnace 10 . Note that in FIG. 1, the heating furnace 10 is shown as a cross section taken along the line AA in FIG.

The container 11 has a cylindrical main body 11a and a cylindrical support portion 11b. The front ends 13a of the six light heating devices 13 are embedded in the openings 11c formed in the side surface of the main body 11a. In addition, the light heating devices 13 are arranged at regular intervals around the axis AX along a plane perpendicular to the axis AX of the reaction cell 90 . The main body 11a of the container 11 fixes each light heating device 13 airtightly from the surroundings. Each optical heating device 13 irradiates heating light containing infrared rays so as to be focused toward the central region of the container 11 . The lid block 12 is a cylindrical member and seals the upper opening 11 d of the container 11 . The lid block 12 has a hole 12a in the center through which the reaction cell 90 is inserted, and airtightly fixes the reaction cell 90 from the surroundings. As a result, the tip of the reaction cell 90 is set in the central region of the container 11 . A tip of a radiation thermometer 15 is embedded at one place on the bottom of the container 11 .

The container 11 and the lid block 12 are made of aluminum and have water cooling channels (not shown) therein. By water-cooling the container 11 and the lid block 12, the light heating device 13 and the reaction cell 90 can be cooled, and the deterioration of the later-described O-ring R attached to the light heating device 13 and the reaction cell 90 can be suppressed. can. In the container 11 and the lid block 12, the surface of the base material is coated with a gold thin film. This thin film efficiently reflects heating light including infrared rays from the light heating device 13 , prevents heating of the container 11 , and assists heating of the lower end 90 b of the reaction cell 90 .

The reaction cell 90 shown in FIG. 3 is used in a state of being evacuated to a vacuum, and holds a quartz sample M in the reduced pressure space at the lower end 90 b of the reaction cell 90 . The reaction cell 90 is made of quartz glass, and consists of a pair of test tube-like tubes 91 and 92 stacked inside and outside. That is, the reaction cell 90 is a double-structured quartz tube, one of which constitutes the inner tube 91 and the other constitutes the outer tube 92 . Each tube 91, 92 has a cylindrical wall portion 91a, 92a and a hemispherical bottom portion 91b, 92b, and the upper ends of both tubes 91, 92 are airtightly joined.

Reaction cell 90 has cavity 93 , gas extraction 94 , and access recess 95 .

The hollow portion 93 is a body portion sandwiched between the outer tube 92 and the inner tube 91 and has an internal space IS. The cavity 93 is airtight when the internal space IS is closed. The internal space IS has a cylindrical space with a substantially uniform thickness and a bottom space with a thickness equal to or smaller than that of the cylindrical space. The cavity 93 has a sample storage space SS at the lower end 90b of the reaction cell 90 in the internal space IS. A sample M is held in the sample storage space SS.

The gas extraction part 94 has a passage Pa and is connected to the upper part of the outer tube 92 in the hollow part 93 of the reaction cell 90 so as to communicate with the internal space IS. The gas extractor 94 extends obliquely upward from the outer tube 92 . The gas extractor 94 is connected to the external recovery line ML shown in FIG. 1 and discharges the gas generated from the sample M to the gas recovery section 21a of the separation processing apparatus 21, which will be described later. The gas extractor 94 holds the extracted gas generated in the reaction cell 90 during the reaction of the sample M while avoiding atmospheric contamination, and recovers the extracted gas after the reaction using the gas recovery unit 21a of the separation processing device 21. make it possible to The extraction gas is held in the reaction cell 90 by separating the gas recovery section 21a and the reaction cell 90 using a needle valve provided in the recovery line ML that connects the gas extraction section 94 and the gas recovery section 21a. ing. A vacuum pump (not shown) is provided in the recovery line ML to reduce the pressure in the reaction cell 90 .

The gas extractor 94 has a cylindrical shape and has a light-absorbing shielding zone 94a in the center. The shielding zone 94a is arranged so as to surround the passage Pa. The shielding zone 94a is formed by joining an opaque quartz tube separately in the gas extraction part 94, and blocks the heating light that propagates through the reaction cell 90 and leaks to the separation processing device 21, specifically the gas recovery part 21a side. Thus, heating and deterioration of the gas recovery portion 21a connected to the connection portion 94b at the tip of the gas extraction portion 94 are prevented. Also, by providing the shielding zone 94a, the O-ring R provided in the gas extraction part 94 for maintaining a high vacuum can be kept sound. An annular groove 94c is formed outside the connection portion 94b of the gas extraction portion 94 . The groove 94c is an O-ring joint for connecting with the gas recovery unit 21a of the separation processing device 21, which is an external device, via the recovery line ML, and can be fitted with an O-ring R that enables an airtight connection. I have to. A high vacuum can be maintained by attaching an O-ring R to the groove 94c to prevent leakage due to pressurization and vacuum. As the O-ring R, for example, an O-ring made of a fluororubber material such as Viton O-ring (registered trademark) is used.

An access recess 95 is formed at the lower end of the inner tube 91 so as to protrude into the sample storage space SS. The access recess 95 is connected to the upper end 90a of the reaction cell 90 via the center side of the inner tube 91. As shown in FIG. The internal heating device 14 is inserted into the access recess 95 .

Since the reaction cell 90 has the structure described above, it is possible to efficiently heat the sample M held in the cavity 93 and to efficiently extract the carbon isotope while maintaining the vacuum state.

As an example of the dimensions of the reaction cell 90, the length of the outer shape of the cavity 93 in the direction of the axis AX is, for example, 25 cm, and the length of the outer shape in the radial direction is, for example, 20 cm. The inner diameter of the hollow portion 93, that is, the interval between the outer tube 92 and the inner tube 91, is substantially uniform in the portion extending in the direction of the axis AX, and is, for example, 5.5 mm. It is narrower than the extended portion. The radial length of the inner side of the cavity 93, that is, the access recess 95 is, for example, 9 mm. The length of the gas extractor 94 is, for example, 8.5 cm.

The light heating device 13 is a combination of a halogen lamp 13b and a mirror 13c. The light heating device 13 collects the heating light emitted from the halogen lamp 13 b and converges it on the lower end 90 b of the reaction cell 90 . A predetermined region can be efficiently heated by irradiating and heating with a plurality of halogen lamps 13b. The halogen lamp 13b is an inert gas such as nitrogen or argon to which a small amount of a halogen gas such as iodine or bromine is added, and is sealed inside the bulb. Luminescence is maintained by a gaseous halogen cycle. The power of the halogen lamp 13b is, for example, 450W. The mirror 13c has a spherical or ellipsoidal reflecting surface and efficiently reflects the heating light. The reflecting surface of the mirror 13c is coated with, for example, a gold thin film. Note that the mirror is not limited to one that performs surface reflection, and may be one that utilizes back surface reflection.

The internal heating device 14 has a thermocouple 14a shown in FIG. 4(A), a tungsten heater 14b shown in FIG. 4(B), and an inert gas introduction pipe 14c shown in FIG. 4(C). Since the internal heating device 14 includes the tungsten heater 14b, even the narrow space inside the reaction cell 90 can be efficiently heated.

The thermocouple 14a is formed by joining a lead wire T1 of Pt and a lead wire T2 of Rh at their ends, and both lead wires T1 and T2 are covered with quartz glass tubes T3 and T4 for short-circuit prevention, respectively. The tungsten heater 14b has a coil portion C1 arranged at the tip and a pair of conducting wires C2 and C3 extending from the coil portion C1. One conducting wire C2 is covered with a quartz glass tube C4 for short circuit prevention. . A tungsten wire is used as the coil portion C1, and wires obtained by connecting a tungsten wire and a nickel wire, for example, are used as the conducting wires C2 and C3 extending from the coil portion C1. The maximum outer diameter of the tungsten heater 14b is, for example, 6 mm. A thermocouple 14a and an inert gas introduction pipe 14c are inserted into the coil portion C1 at the tip. The inert gas introduction pipe 14c is made of quartz glass and has a ventilation hole E. The inert gas introduction pipe 14c supplies Ar gas at a predetermined flow rate to the periphery of the coil portion C1 of the tungsten heater 14b through the ventilation hole E. As shown in FIG. Ar gas prevents the tungsten heater 14b from being oxidized. Since the internal heating device 14 has the inert gas introduction pipe 14c and the quartz glass tubes T3, T4, and C4, deterioration of the thermocouple 14a and the tungsten heater 14b can be prevented under extremely high temperatures.

The external heating driving device 40 operates under the control of the control device 30, adjusts the lighting timing, lighting time, etc. of the light heating device 13, and enables rapid and accurate heating of the lower end 90b of the reaction cell 90. FIG. The external heating driving device 40 operates while feeding back the measurement results from the radiation thermometer 15 and the thermocouple 14a, and raises the sample M held in the sample storage space SS to a target temperature, specifically 1550°C to 1650°C. heat to The shorter the time required for temperature rise, the better. Specifically, heating to the target temperature, specifically the temperature at which quartz undergoes phase transition, is achieved in 5 to 10 minutes. Since the shorter the time required for temperature rise, the less contamination, ^{the 14} C detection accuracy can be improved. The sample M is obtained by pulverizing a rock containing the target nuclide and purifying it into quartz, and is heated by the optical heating device 13 until a target phase transition occurs. Sample M was taken at a destination, specifically quartz containing ¹⁴ C generated in situ. Sample M releases ¹⁴ C or CO gas containing ¹⁴ C when heated until the desired phase transition occurs.

The radiation thermometer driving device 50 operates under the control of the control device 30, and measures the surface temperature of the lower end 90b of the reaction cell 90, that is, the temperature of the sample M held in the sample storage space SS without contact. The internal heating driving device 60 operates under the control of the control device 30, and auxiliary heats the lower end 90b of the reaction cell 90 by adjusting the energization of the tungsten heater 14b. By the tungsten heater 14b, the sample M can be uniformly heated, and phase transition leakage of the input sample M can be eliminated. The temperature detection circuit 70 operates under the control of the control device 30, and measures the temperature of the lower end 90b of the reaction cell 90 from inside via the thermocouple 14a. The inert gas supply device 80 operates under the control of the control device 30 and prevents the tungsten heater 14b from oxidizing while the sample M is being heated.

The separation processing device 21 has a gas recovery section 21a and a separation processing section 21b. The separation processing device 21 operates under the control of the control device 30, and oxidizes and purifies the extracted gas recovered by the gas recovery section 21a.

The gas recovery unit 21a recovers the extraction gas retained in the reaction cell 90, specifically the gas extraction unit 94, during the reaction from the gas extraction unit 94 after the reaction. The gas recovery unit 21a recovers the extracted gas by cooling the cryogenic trap with liquid nitrogen, for example.

The separation processing section 21b is connected to the gas recovery section 21a by a processing line NL. The separation processing unit 21b converts the CO gas containing ¹⁴ C generated in situ into CO ₂ gas by oxidizing it under a carrier gas, and removes unnecessary gas components using a trap or the like. The separation processing unit 21b graphitizes the CO ₂ gas containing ¹⁴ C and the like.

The nuclide measurement device 22 measures ^14C . The nuclide measurement device 22 is, for example, an accelerator mass spectrometry (AMS) provided in a separate building, and measures the amount of ¹⁴ C, ^{12 C, etc. from graphite containing 14 C} , etc. at the atomic number level. .

An example of a sample M extraction and analysis method using the isotope extraction analyzer 100 will be described below with reference to FIG.

First, quartz, which is the sample M, is pretreated (step S11). Specifically, rock is crushed, quartz is beneficiated and washed. The pretreated sample M is stored in the sample storage space SS of the reaction cell 90 . As the sample M, for example, a quartz sample collected from deep underground that does not contain in situ generated ¹⁴ C can be used in order to measure the background level. Also, known quartz samples whose ¹⁴ C concentration has reached radial equilibrium can be used to measure the extraction efficiency. Measurement results of these samples can be used for calibration of other samples.

Next, the reaction cell 90 containing the sample M is heated by the heating furnace 10 to extract ¹⁴ C (step S12). Specifically, the sample M is heated at, for example, 450° C. or 500° C. under vacuum to remove meteoric ¹⁴ C from the atmosphere that causes contamination. Thereafter, the reaction cell 90 is filled with a carrier gas composed of oxygen or O ₂ —CO ₂ —He, and the sample M is heated under vacuum at, for example, 1550° C. or 1650° C. for about 10 minutes to generate ¹⁴ C in situ. Alternatively, a CO component containing ¹⁴ C is recovered from the gas extraction portion 94 of the reaction cell 90 . Specifically, during the reaction of the sample M, the extraction gas is retained in the gas extraction part 94 while avoiding atmospheric contamination. After the reaction of the sample M, the needle valve provided in the recovery line ML is opened to open the recovery line ML, and the gas recovery unit 21a incorporated in the separation processing apparatus 21 extracts using a low-temperature trap cooled by liquid nitrogen. Collect gas. As described above, by extracting ¹⁴ C generated in situ under a high vacuum in a short time, the generation of ¹⁴ C derived from the atmosphere can be prevented, and the generation of contamination can be prevented. .

Next, in the separation processing unit 21b of the separation processing device 21, the extracted ¹⁴ C or CO is oxidized (step S13). Specifically, the gas generated from the sample M is oxidized by a catalytic reaction using a carrier gas composed of, for example, oxygen or O ₂ —CO ₂ —He and platinum to generate CO ₂ .

Next, in the separation processing section 21b of the separation processing device 21, the oxidized CO ₂ is purified (step S14). Specifically, gases other than water vapor and CO ₂ are removed from the gas that has passed through step S13 by means of a trap or the like.

Next, in the separation processing section 21b of the separation processing device 21, the refined CO ₂ is graphitized by reduction with a metal catalyst (step S15). Specifically, purified CO ₂ and H ₂ are mixed and reduced using iron as a catalyst to produce graphite. Graphite may also be produced by a reduction reaction of purified CO ₂ using a combination of zinc and iron or cobalt as a catalyst. The graphite generated by the separation processing device 21 is packed by pressing graphite powder into an aluminum tube and attached to the analysis unit of the nuclide measuring device 22 .

Finally, the graphitized C is used to quantify C in the nuclide measuring device 22 (step S16). Specifically, by irradiating a target with positive cesium ions using AMS, negative ion carbon is generated from graphite. Analyze the mass of the isotopes. In AMS, the mass can be sorted by passing it through a magnetic field and the isotope ratios of, for example, ¹⁴ C, ¹³ C, ¹² C can be measured.

In the isotope extraction apparatus 100a, the sample M in the reaction cell 90 is efficiently heated by the irradiation heating from the outside of the reaction cell 90 by the light heating device 13 and the heating from the inside by the internal heating device 14. It can be carried out. As a result, the temperature can be raised to a temperature at which the sample M such as quartz undergoes a phase transition in a short period of time, and the occurrence of contamination can be prevented. Further, since the isotope extraction apparatus 100a does not use a solvent in the process of extracting carbon isotopes, the sample M can be reused for extraction of other isotopes after extraction of carbon isotopes.

The isotope extraction analysis device 100 incorporating the isotope extraction device 100a can be used as a sample extraction analysis system for surface irradiation dating. exposure age can be measured.

〔others〕
Although the present invention has been described with reference to the embodiments, the present invention is not limited to the above embodiments. For example, the halogen lamp 13b is used as the light heating device 13, but other light sources such as an infrared carbon lamp and a laser may be used. When a laser is used as the light source, the irradiation area is more localized than the halogen lamp 13b.

Further, in the above embodiment, six light heating devices 13 are arranged around the axis AX of the reaction cell 90, but the arrangement and number can be changed as appropriate. Also, the optical heating device 13 may be arranged in two stages.

In the above-described embodiment, the shielding zone 94a provided in the gas extraction part 94 of the reaction cell 90 is formed by joining an opaque quartz tube separately. It may be formed by fusing opaque glass to a quartz tube.

In the above embodiment, the heating temperature and heating time in the heating furnace 10 can be changed as appropriate.

DESCRIPTION OF SYMBOLS 10... Heating furnace 11... Container 11a... Main body 11b... Support part 12... Lid block 12a... Hole 13... Light heating device 13b... Halogen lamp 13c... Mirror 14... Internal heating device 14a... Thermocouple 14b Tungsten heater 14c Inert gas introduction pipe 15 Radiation thermometer 16 Frame 21 Separation device 21a Gas recovery unit 21b Separation unit 22 Nuclide measuring device 30... Control device 40... External heating drive device 50... Radiation thermometer drive device 60... Internal heating drive device 70... Temperature detection circuit 80... Inert gas supply device 90... Reaction cell 91... Inner tube 91a, 92a Wall portion 91b, 92b Bottom portion 92 Outer tube 93 Cavity portion 94 Gas extraction portion 94a Barrier zone 94b Connection portion 94c Groove 95 Access concave portion 100 Isotope extraction and analysis device 100a Isotope extraction device C1 Coil section C2, C3 Lead wire C4 Quartz glass IS Internal space R O ring SS Sample storage space T1, T2 Lead wire, T3...Quartz glass tube

Claims (6)

a heating furnace for heating to extract carbon isotopes from quartz samples;
a reaction cell having a structure in which a pair of test tube-like tubes are stacked vertically and holding the quartz sample in an internal space;
with
The reaction cell holds the extracted gas generated in the reaction cell during the reaction of the quartz sample while avoiding atmospheric contamination, and recovers the extracted gas after the reaction using the gas recovery unit of the separation processing apparatus. enable
The heating furnace has a plurality of light heating devices provided around the outside of the reaction cell for heating the quartz sample by collecting light, and an internal heating device provided inside the reaction cell. Isotope extractor. The reaction cell is a double-structured quartz tube, and includes a hollow portion that is airtight with the internal space closed and holds the quartz sample, and a hollow portion that is provided above the hollow portion and is connected to the outside. 2. The isotope extraction device according to claim 1, comprising a gas extraction part for releasing gas generated from said quartz sample by means of a gas extraction part, and an access recess for inserting said internal heating device inside. 3. Isotope extraction apparatus according to any one of claims 1 and 2, wherein the optical heating device comprises a halogen lamp and a mirror. The isotope extraction device according to any one of claims 1 to 3, wherein the internal heating device includes a tungsten heater. The isotope extraction device according to any one of claims 2 to 4, wherein the gas extraction unit has a light-absorbing shielding zone. The isotope extraction device according to any one of claims 2 to 5, wherein the gas extraction part has a groove for an O-ring joint for connection with an external device.

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