CN106872256B - Amorphous laser ablation pond - Google Patents

Abstract

The invention provides an amorphous laser ablation pool, which includes a closed cavity, the cavity is composed of a TP casing and a base at the bottom of the casing, the top of the TP casing is provided with a through hole, and the edge of the through hole is provided with wrapping, The transparent observation window is embedded in the edging of the top of the TP case. The observation window is equipped with a calcium fluoride window and a local extraction tube. The base is equipped with a sample positioning plate, and the upper surface of the sample positioning plate is provided with a set of positioning pins. There is a positioning pin assembly, the side wall of the base is provided with a carrier gas inlet and a carrier gas exhaust port, and magnets are provided under the sample positioning plate and in the depression of the base. The shape and volume of samples placed inside the amorphous laser ablation sample cell provided by the present invention are free, and can provide non-destructive analysis for samples. When used in conjunction with LA‑ICP‑MS, samples of any size and shape can be placed without positional effects, and can be placed More routine samples, less frequency of sample change, no position effect, improve the accuracy and work efficiency of analysis and testing.

Description

Amorphous laser ablation cell

technical field

The invention relates to an amorphous laser ablation pool, which belongs to the field of laser ablation plasma light and mass spectrometry analysis.

Background technique

LA-ICP-MS in-situ microanalysis (in-situ microanalysis) is one of the main testing techniques for obtaining trace elements and isotopes of samples in different fields. It not only avoids the tedious and time-consuming wet chemical digestion process, but also can Revealing the details of micron-scale element/isotope spatial changes in solid matter, with the advantages of in-situ, real-time, fast, accurate, and non-destructive analysis, as well as high sensitivity and spatial resolution, it has become a research hotspot in in-situ micro-area testing technology in recent years. It provides important support for innovative research in many fields such as metallurgy, environment, biology, chemistry, criminal investigation and archaeology. However, due to the limitation of the volume of the current ablation cell, the standard LA-ICP-MS laser ablation system can only perform non-destructive analysis on small volume samples with a thickness of ≤1 cm and a diameter of ≤4 cm. However, in the research fields of geology and environment, large-volume precious and indestructible samples (such as ancient fossils, precious meteorites, extraterrestrial materials, large mantle enclaves, etc.) and large-volume physical evidence samples (such as ancient ceramics) in the fields of archaeology and criminal investigation , ancient jade, copper, etc.), due to the particularity and rareness of the samples, destructive pretreatment cannot be performed. This problem is the bottleneck problem that restricts the LA-ICP-MS in situ micro-area non-destructive analysis of large-volume precious and unbreakable samples. .

Contents of the invention

In order to solve the deficiencies of the prior art, the present invention provides an amorphous laser ablation sample cell, the shape and volume of the sample placed inside are free, and it combines the advantages of closed and open ablation cells, which can be used for geology, environment, materials, etc. Provide non-destructive analysis of large-volume and special-shaped samples in the fields of biology, criminal investigation, archaeology, etc.; combining the amorphous laser ablation sample cell with LA-ICP-MS (laser ablation inductively coupled plasma mass spectrometry), you can place samples of any size and shape The sample has no position effect, which solves the problem of signal diffusion and dilution due to the large volume of the ablation cell in the laser micro-analysis sampling, and the memory effect caused by the gravity deposition of aerosols in places where the airflow is weak; at the same time , the amorphous laser ablation sample cell can place more conventional samples, reduce the frequency of sample change, have no position effect, and improve the accuracy and work efficiency of analysis and testing.

The technical solution adopted by the present invention to solve the technical problem is: an amorphous laser ablation pool is provided, including a closed cavity, the cavity is composed of a bell-shaped TP casing and a base at the bottom opening of the TP casing, The top of the TP case is provided with a through hole, and the edge of the through hole is provided with wrapping, and the transparent observation window is embedded in the wrapping on the top of the TP case through interference fit, and a circular through hole is provided in the center of the observation window. A round pie-shaped calcium fluoride window is embedded in the through hole, and the calcium fluoride window and the through hole are sealed and fixed by an O-ring. The observation window is provided with a sampling channel, and a sealing ball is installed in the sampling channel. The local extraction tube is inserted into the central inner hole of the sealing ball and moves back and forth along the axial direction of the local extraction tube; the upper surface of the base is a concave structure, and a sample positioning plate is placed in the depression; the upper surface of the sample positioning plate is provided with a A set of positioning pin counterbore, wherein at least one positioning pin counterbore is placed with a positioning pin assembly, the positioning pin assembly is composed of more than one positioning pin connected up and down end to end, one end of the positioning pin is a round head, and the other end is a The positioning counterbore matching the round head, the positioning pin at the bottom is directly inserted into the positioning pin counterbore of the sample positioning plate; the side wall of the base is provided with a carrier gas inlet and a carrier gas exhaust port, and the sample positioning plate A magnet is respectively provided at the two ends of one of the diameters below, and a magnet is respectively provided at the corresponding positions of the recesses of the base.

The number of sealing balls in the injection channel is 2.

A set of positioning pin assemblies is radially evenly distributed on the surface of the sample positioning plate from the center of the sample positioning plate.

A sealing and fixing ring is provided between the TP casing and the base.

The bottom of the TP cover is provided with hemming, and the side wall of the base is provided with two positioning grooves for fixing the hemming structure and a fixing buckle fixed with a knurled thumb screw. The snaps are the same distance from both positioning slots.

The side wall of the base is provided with 1 carrier gas inlet and 3 carrier gas outlets, and the distance between adjacent carrier gas outlets and adjacent carrier gas inlets and carrier gas outlets is the same.

The beneficial effect that the present invention has based on its technical scheme is:

(1) The base of the outer cavity of the amorphous laser ablation pool of the present invention, the observation window and the transparent elastic casing made of special TP synthetic materials form a self-sealing, and there is almost no element precipitation in the ablation cavity, which ensures an extremely low process background;

(2) The amorphous laser ablation cell of the present invention can place samples of any size and shape without position effect. By assembling positioning pin components to meet the adjustment of different angles and heights, in order to achieve accurate local positioning, large-volume or special-shaped samples, The matching between the base of the outer cavity and the TP cover can realize the function, which solves the problem of signal diffusion and dilution caused by the large volume of the ablation cell in the laser micro-area analysis and sampling, and the problem of aerosol generation in places where the airflow is weak. Bottleneck problems such as memory effect and long cleaning time caused by gravity deposition;

(3) The amorphous laser ablation cell of the present invention places more conventional samples and has no position effect, and adjusts the position of each special sample to be collected to the best acquisition position through the local extraction device, effectively improving the sampling time and greatly Reduce cleaning time, sample change time, reduce fractionation, improve the accuracy and work efficiency of analysis and testing.

Description of drawings

Fig. 1 is a schematic diagram of the overall structure of the amorphous laser ablation cell of the present invention.

Fig. 2 is a schematic diagram of the structure of the TP casing of the amorphous laser ablation cell of the present invention.

Fig. 3 is a schematic diagram of the structure of the sample positioning plate of the amorphous laser ablation cell of the present invention.

Fig. 4 is a schematic diagram of the base of the amorphous laser ablation cell of the present invention.

Fig. 5 is a schematic diagram of the observation window structure of the amorphous laser ablation cell of the present invention.

In the figure: 1-observation window, 2-TP cover, 3-base, 4-sealing fixed ring, 5-sample positioning plate, 6-calcium fluoride window, 7-O-type sealing ring, 8-local extraction tube, 9-Sealing ball, 10-Location pin, 11-Fixed buckle, 12-Knurled thumb screw, 13-Carrier gas inlet, 14-Carrier gas exhaust, 15-Location pin counterbore, 16-Location Slot, 17-through hole, 18-encapsulation on the top of the TP case, 19-encapsulation on the bottom of the TP case, 20-magnet, 21-injection channel.

detailed description

The present invention will be further described below in conjunction with drawings and embodiments.

Referring to Fig. 1 to Fig. 5, the present invention provides an amorphous laser ablation pool, comprising a closed cavity, the cavity is composed of a bell-shaped TP casing 2 and a base 3 at the bottom opening of the casing, the TP casing The top of the shell 2 is provided with a transparent observation window 1. The specific implementation method is that the top of the TP case is provided with a through hole, and the edge of the through hole is provided with a wrapping edge. The transparent observation window is embedded in the wrapping 18 on the top of the TP case through interference fit.

A transparent observation window 1 is sealed and embedded in the observation window through hole 18, and a circular through hole 17 is arranged in the center of the observation window 1, and a round pie-shaped calcium fluoride window 6 is embedded in the through hole 17, and the calcium fluoride window 6 and the through hole 17 are sealed and fixed by an O-ring 7 . The observation window 1 is provided with a sampling channel 21, and a sealing ball 9 is installed in the sampling channel. The number of sealing balls in the sampling channel can be 2, which are respectively close to the two ends of the sampling channel 21, and the partial extraction tube 8 is interspersed. In the central inner holes of the two sealing balls 9 and along the axial direction of the partial extraction pipe 8, move back and forth.

The upper surface of the base 3 is a concave structure, and a sample positioning disc 5 is placed in the depression; a group of positioning pin counterbores 15 are provided on the upper surface of the sample positioning disc, and a positioning pin assembly is placed in at least one positioning pin counterbore 15, The locating pin assembly is composed of more than one locating pin 10 connected up and down end to end. One end of the locating pin 10 is a round head, and the other end is a positioning counterbore matching the round head. The lowermost locating pin 10 is directly inserted into the sample. In the counterbore 15 of the positioning pin of the positioning plate 5; the side wall of the base 3 is provided with a carrier gas inlet 13 and a carrier gas exhaust 14. The number of the carrier gas inlet 13 and the carrier gas outlet 14 on the side wall of the base 3 is 1 and 3 respectively, the adjacent carrier gas outlet 14 and the adjacent carrier gas inlet 13 and The carrier gas exhaust ports 14 have the same distance and are distributed on the side wall at 90°, which can ensure rapid and uniform exhaust.

A group of said positioning pin assemblies is radially evenly distributed on the surface of the sample positioning plate 5 from the center of the sample positioning plate 5 .

A magnet is respectively provided at the two ends of a diameter of the sample positioning plate 5 , and a magnet 20 is provided at the corresponding position of the depression of the base.

A sealing ring 4 is provided between the TP case 2 and the base 3 .

The bottom of the TP case 2 is provided with a hemming 19, and the side wall of the base is provided with two positioning grooves 16 for fixing the hemming 19 at the bottom of the TP case and a knurled thumb screw 12 for fixing The fixed buckle 11, the distance from the fixed buckle 11 to the two positioning grooves is the same.

The use process of an amorphous laser ablation cell of the present invention is as follows: when getting a sample, adjust the positioning pin on the sample positioning plate to a suitable position and height, put the sample on the positioning pin, and put the sealing and fixing ring on the TP cover On the lower hemming structure of the shell, place the hemming structure of the TP cover in the positioning groove of the base, press the sealing and fixing ring through the knurled hand screw and the fixing buckle, and the thrust of the inclined plane makes the air seal. A calcium fluoride window equipped with an O-ring seal is placed in the through hole in the center of the observation window to seal it. Open the carrier gas exhaust port, and pass the carrier gas (inert gas such as argon or helium) through the carrier gas inlet for about 30 seconds to discharge the air in the chamber to avoid the remaining air causing the instrument to turn off, and then close the carrier gas exhaust mouth. The laser lens is fixed, and the sample is laser ablated through the calcium fluoride window lens. The aerosol ablated by the laser is led to the mass spectrometer through the local extraction device for subsequent analysis. During the process, the local extraction device can move back and forth to adjust the best position.

The invention provides an amorphous laser ablation sample pool, the shape and volume of the sample placed inside are free, and it has the advantages of both closed and open ablation pools, and can be used in geology, environment, materials, biology, criminal investigation, archaeology and other fields. Provide non-destructive analysis of large volume and special shape samples; the combination of amorphous laser ablation sample cell and LA-ICP-MS (laser ablation inductively coupled plasma mass spectrometry) can place samples of any size and shape without position effect, solving the problem of In the laser micro-area analysis and sampling, due to the large volume of the ablation cell, the problem of signal diffusion and dilution, and the gravity deposition of the aerosol in the place where the gas flow is weak will cause the memory effect and other problems; at the same time, the amorphous laser ablation sample cell More conventional samples can be placed, the frequency of sample change is reduced, there is no position effect, and the accuracy and work efficiency of analysis and testing are improved.

Claims (6)

1. a kind of amorphous laser ablation pond, including airtight cavity, it is characterised in that：The cavity is covered by bell TP cases and TP Base composition at shell bottom opening, the TP cases top are provided with through hole, and through hole edge is provided with bound edge, and transparent windows pass through For interference fit in the bound edge at the top of TP cases, the center of the observation window is provided with a manhole, and one is inlaid with through hole Round pie calcium fluoride windows, between the calcium fluoride windows and through hole by O-ring seal seal fix, observation window be provided with into Sample duct, ball sealer is provided with sample introduction duct, and local extraction tube is interspersed in the central bore of the ball sealer and carried along local Take the movable axially back and forth of pipe；The upper surface of the base is sunk structure, and it is equipped with Sample location disk in being recessed；Sample location Disk upper surface is provided with one group of alignment pin counterbore, and pin assembly, the positioning are placed with wherein at least one alignment pin counterbore Pin assemblies are made up of alignment pin of more than one head and the tail connection up and down, and one end of the alignment pin be round end, the other end for and circle The positioning counterbore of head matching, the alignment pin of bottom are directly inserted in the alignment pin counterbore of Sample location disk；The base side wall Provided with carrier gas air inlet and carrier gas exhaust outlet, the end positions below the Sample location disk positioned at one bar diameter are respectively equipped with One magnet, the depression relevant position of base are respectively provided with a magnet.

2. amorphous laser ablation pond according to claim 1, it is characterised in that：Ball sealer number in the sample introduction duct Measure as 2.

3. amorphous laser ablation pond according to claim 1, it is characterised in that：Pin assembly is with sample described in one group The radial surface for being uniformly distributed in Sample location disk in the center of positioning disk.

4. amorphous laser ablation pond according to claim 1, it is characterised in that：It is provided between the TP cases and base Seal retainer ring.

5. amorphous laser ablation pond according to claim 1, it is characterised in that：The TP casing bases are provided with bound edge, The base side wall is externally provided with two locating slots for being used to fix the binding structure and one is fixed with annular knurl hand the turn of the screw Fixed card buckle, the fixed card buckle is identical to the distance of two locating slots.

6. amorphous laser ablation pond according to claim 1, it is characterised in that：The base side wall is provided with 1 carrier gas Air inlet and 3 carrier gas exhaust outlets, adjacent carrier gas exhaust outlet and adjacent carrier gas air inlet and carrier gas exhaust outlet are apart from phase Together.