A flexible laser ablation pool and working method

Abstract

The invention discloses a flexible laser ablation pool and a working method, comprising a laser system, a flexible ablation pool and a sample stand. The flexible ablation pool is provided with a TPR cover shell, the top of the TPR cover shell is connected to an upper support plate, the lower periphery of the TPR cover shell is connected to a lower fixed flexible ring, a plurality of full-thread screws are connected between the upper support plate and the lower fixed flexible ring, the full-thread screws adjust the height of the bottom of the TPR cover shell through a fixing nut, the bottom of the TPR cover shell is attached and sealed to the sample surface, a closed cavity is formed between the TPR cover shell and the sample, and the sample detection part becomes the base of the flexible ablation pool; the sample is placed on a sample support provided on the sample stand, clamping plates are provided on both sides of the sample support, the bottom of the sample support is connected to a rotating motor through a turntable, and the bottom of the rotating motor is connected to a lifting cylinder to control the rotation and lifting of the sample support; the invention turns a sample at a certain point of the measured sample into the base of the closed cavity of the laser ablation pool, so as to realize multi-point positioning analysis of the sample.

Description

Technical Field

[0001] The invention relates to the technical field of laser ablation and sample plasma mass spectrometry analysis, and in particular to a flexible laser ablation cell and a working method. Background Art

[0002] In-situ microanalysis has become a necessary analytical method in the fields of atomic energy, biology, medicine, chemistry, environmental science, food science, forensic medicine, criminal investigation science, chemical engineering, petrochemical engineering, geology, cosmology, etc. Its analytical methods are also constantly developing and improving, and the instruments and equipment used are different.

[0003] At present, the laser ablation cell commonly used in LA-ICP-MS can only analyze small-volume samples with a thickness of ≤1cm and a diameter of ≤4cm. In the fields of geology, environment, archaeology, etc., some large-volume, indestructible precious samples (such as ancient fossils, precious meteorites, extraterrestrial materials, large mantle inclusions, ancient ceramics, ancient jades, ancient bronzes, etc.) cannot be destructively pre-treated due to the special and rare nature of the samples. Patent ZL201710101519.2 Amorphous Laser Ablation Cell satisfies the in-situ analysis of large-volume amorphous samples to a certain extent. However, this patent still places the sample into the ablation cell like the traditional laser ablation cell. In this way, for the positioning analysis of certain parts of some samples with super-large volume or special shape, the equipment used in this patent will not meet the requirements, and it is impossible to perform fixed-point positioning analysis on such samples. Therefore, it is urgent to design a flexible laser ablation cell that combines samples and ablation cells to solve the limitation that the existing laser ablation cell can only put the sample into the ablation cell and cannot perform multi-position fixed-point positioning analysis on the sample. Summary of the invention

[0004] In view of the problems existing in the prior art, the object of the present invention is to provide a flexible laser ablation pool and a working method.

[0005] The technical solution adopted by the present invention to solve its technical problems is: a flexible laser ablation pool, including a laser system, a flexible ablation pool and a sample stand, the flexible ablation pool is provided with a TPR cover, the top of the TPR cover is connected to an upper support plate, the lower periphery of the TPR cover is connected to a lower fixed flexible ring for supporting and fixing the TPR cover, a plurality of full-thread screws are connected between the upper support plate and the lower fixed flexible ring, the full-thread screws adjust the height of the bottom of the TPR cover through a fixing nut, and are used for the bottom of the TPR cover to be attached and sealed to the sample surface, a closed cavity is formed between the TPR cover and the sample, and the plane of the sample detection part becomes the base of the flexible ablation pool;

[0006] The sample is placed on a sample support provided on the sample stand. Clamps are provided on both sides of the sample support for stably fixing the sample. The bottom of the sample support is connected to a rotating motor through a turntable. The bottom of the rotating motor is connected to a lifting cylinder for controlling the rotation and lifting of the sample support.

[0007] Specifically, the lower fixed flexible ring is provided with a threaded hole compatible with the full-thread screw, which is used to fix the bottom of the full-thread screw to the lower fixed flexible ring. The upper support plate and the lower fixed flexible ring are provided with a through hole at a relative position, and the upper part of the full-thread screw passes through the through hole. The full-thread screw and the upper and lower support plates are respectively provided with an upper fixing nut and a lower fixing nut, which are used to control the distance between the upper support plate and the lower fixed flexible ring on each side by adjusting the upper fixing nut and the lower fixing nut.

[0008] Specifically, an observation window is provided in the middle of the upper support plate, and calcium fluoride glass is installed in the observation window. The laser beam of the laser system enters the closed cavity through the calcium fluoride glass. The laser beam is emitted by a laser emitter provided in the laser system. The laser system is fixed together with the flexible ablation pool, and the laser beam is used to irradiate the bottom center position of the flexible ablation pool.

[0009] Specifically, a monitoring bracket is installed on the upper support plate and at the observation window, and a fixed-point monitoring camera is installed on the monitoring bracket. The fixed-point monitoring camera is connected to the monitoring host for imaging. The fixed-point monitoring camera is focused on the center position of the bottom of the flexible erosion pool irradiated by the laser beam, and is used to fine-tune the measured point on the sample to coincide with the laser beam irradiation point.

[0010] Specifically, the TPR housing is also provided with an air inlet hole and an air outlet hole for controlling the inlet and outlet of carrier gas.

[0011] Specifically, the upper surface of the sample support is covered with a plastic-sprayed steel plate or a plastic-sprayed aluminum alloy plate, and the bottom of the sample support is installed on a turntable, which is connected to a rotating motor for controlling the rotation of the sample support to adjust the sample detection position through the rotating motor. The bottom of the rotating motor is installed on a motor fixing plate, and the bottom of the motor fixing plate is installed on the top of the cylinder rod of the lifting cylinder. The bottom of the lifting cylinder is fixed on a moving base, and the lifting cylinder is used to control the lifting of the sample support. A plurality of moving wheels with a brake structure are installed at the bottom of the moving base.

[0012] Specifically, the sample support adopts a hollow structure, and two splint motors are staggered inside the sample support. The splint motor is connected to a lead screw, and the other end of the lead screw is installed on the side wall of the sample support through a bearing. A nut seat is threaded on the lead screw, and the upper part of the nut seat is connected to a splint support rod. The splint support rod passes through a slide groove provided on the sample support, and the top of the splint support rod is connected to a splint, which is used for the splint motor to control the movement of the splint through the lead screw and the nut seat.

[0013] Specifically, the splint motor, the rotating motor and the lifting cylinder are all electrically connected to an electric control box, and the electric control box is installed on the mobile base.

[0014] A method for operating a flexible laser ablation cell comprises the following steps:

[0015] 1) Mark the test point on the sample to be tested, place the sample to be tested on the sample support, control the clamping plate motor through the control button in the electric control box, so that the clamping plates on both sides clamp or support the fixed sample, push the sample stand to the bottom of the flexible erosion tank through the moving wheel, control the lifting cylinder through the control button in the electric control box, control the sample to contact the bottom of the TPR cover, and then control the rotating motor to make the marked point on the sample to be tested located inside the TPR cover;

[0016] 2) The image of the test point of the sample to be tested is monitored by the monitoring host, and the sample to be tested is fine-tuned through the operation steps in step 1 so that the marked point is located at the center of the image, that is, the marked point is located at the irradiation point of the laser beam, and the monitoring host records the position of the focal length of the fixed-point monitoring camera;

[0017] 3) For the concave part of the sample surface, adjust the upper fixing nut and the lower fixing nut here so that the bottom of the TPR cover goes down to the concave part. Similarly, for the convex part of the sample surface, adjust the upper fixing nut and the lower fixing nut here so that the bottom of the TPR cover is lifted up and close to the convex part.

[0018] 4) After carefully adjusting the TPR cover, fill the small gap between the sample and the TPR cover with plasticine to form a closed cavity between the TPR cover and the sample, then turn on the laser transmitter to allow the laser beam to enter the closed cavity through the observation window and hit the sample, and then analyze the sample using the LA-MC-ICPMS device or LA-IR-ICPMS device;

[0019] 5) After one part of the sample is tested, the rotation and movement of the sample is controlled by the lifting cylinder, the rotating motor and the moving wheel, the next point to be tested on the sample is selected, and the height of the point to be tested of the sample in the flexible ablation tank is adjusted according to the position of the focal length of the fixed-point monitoring camera recorded by the monitoring host, so that the height of each test point is consistent, that is, the height of the laser beam irradiated on the sample is consistent, and steps 1-4 are repeated for sample detection and analysis.

[0020] The present invention has the following beneficial effects:

[0021] The flexible laser ablation cell and working method designed in the present invention convert the sample "plane" where a certain point of the measured sample is located into the base of the closed cavity of the laser ablation cell. This design greatly relaxes the volume and shape of the measured sample, and adjusts the posture of the measured sample and quickly replaces the detection point through the designed adjustable sample stand, so as to achieve quick replacement of the detection point for fixed-point positioning analysis and realize multi-point positioning analysis of the sample; there is no position effect, so the accuracy of sample analysis is guaranteed; a number of full-thread screws are arranged around the designed ablation cell, so as to facilitate the height adjustment of the flexible fixing ring at the bottom of the TPR cover shell according to the concave and convex surface of the sample, so that the bottom edge of the TPR cover wall is in better contact with the sample surface, and the multi-point positioning analysis of samples with extra-large volume or special shape is realized through the sealing of plasticine. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a schematic diagram of the overall structure of the flexible laser ablation cell.

[0023] Figure 2 It is a schematic diagram of the structure of the flexible erosion pool.

[0024] Figure 3 This is a top view of the flexible denudation pond.

[0025] Figure 4 It is a schematic diagram of the transmission structure of the splint.

[0026] In the figure: 1-flexible ablation pool; 2-sample stand; 3-laser system; 4-sample; 101-PTR cover; 102-upper support plate; 103-lower fixed flexible ring; 104-full-thread screw; 105-upper fixing nut; 106-lower fixing nut; 107-sealed cavity; 108-inlet pipe hole; 109-outlet pipe hole; 110-observation window; 111-calcium fluoride glass; 201-sample support; 202-rotating motor; 203-motor fixing plate; 204-lifting cylinder; 205-clamp; 206-clamp motor; 207-screw; 208-nut seat; 209-bearing; 210-clamp support rod; 211-electric control box; 212-movable base; 213-moving wheel; 301-laser emitter; 302-laser beam. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely further describe the technical solutions in the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0028] like Figure 1-4As shown, a flexible laser ablation pool includes a laser system 3, a flexible ablation pool 1 and a sample stand 2, wherein the flexible ablation pool 1 is provided with a TPR housing 101, the top of the TPR housing 101 is connected to an upper support plate 102, the lower periphery of the TPR housing 101 is connected to a lower fixed flexible ring 103 for supporting and fixing the TPR housing 101, a plurality of full-thread screws 104 are connected between the upper support plate 102 and the lower fixed flexible ring 103, and the lower fixed flexible ring 103 is provided with threaded holes adapted to the full-thread screws 104, for fixing the bottom of the full-thread screws 104 to the lower fixed flexible ring 103 On the fixed flexible ring 103, a through hole is provided at the relative position between the upper support plate 102 and the lower fixed flexible ring 103, and the upper part of the full-thread screw 104 passes through the through hole. The full-thread screw 104 and the upper and lower parts of the upper support plate 102 are respectively provided with an upper fixing nut 105 and a lower fixing nut 106, which are used to control the distance between each upper support plate 102 and the lower fixed flexible ring 103 by adjusting the upper fixing nut 105 and the lower fixing nut 106. The lower fixed flexible ring 103 adopts a soft ring made of TPR material, and the TPR cover 101 and the lower fixed flexible ring 103 can be integrally formed. The full-thread screw 104 adjusts the height of the bottom of the TPR cover 101 and the lower fixed flexible ring 103 through the fixing nut, and is used for the bottom of the TPR cover 101 to be attached and sealed to the surface of the sample 4, and a closed cavity 107 is formed between the TPR cover 101 and the sample 4, and the plane of the detection part of the sample 4 becomes the base of the flexible erosion pool 1.

[0029] An observation window 110 is provided in the middle of the upper support plate 102, and a calcium fluoride glass 111 is installed in the observation window 110. The laser beam 302 of the laser system 3 enters the closed cavity 107 through the calcium fluoride glass 111, and the laser beam 302 is emitted by the laser emitter 301 provided by the laser system 3. A monitoring bracket is installed on the upper support plate 102 and at the observation window 110. A fixed-point monitoring camera is installed on the monitoring bracket. The fixed-point monitoring camera is connected to the monitoring host for imaging. The fixed-point monitoring camera is focused at the bottom center position of the flexible ablation pool 1 irradiated by the laser beam, and is used to fine-tune the point to be measured on the sample 4 to coincide with the point irradiated by the laser beam, so as to achieve accurate positioning of the point to be measured on the sample. The TPR cover 101 is also provided with an air inlet pipe hole 108 and an air outlet pipe hole 109, which are used to control the inlet and outlet of the carrier gas, so as to bring the aerosol formed by the laser ablation sample into the analysis system.

[0030] Due to the different shapes of the samples 4, the curved shapes of the test points of the samples 4 are also different. When the lowest point of the TPR cover 101 is the same, the position of the test point of the steeper curved surface of the sample 4 will be higher, and the test point of the flatter curved surface will be lower. According to the position of the focal length of the fixed-point monitoring camera recorded by the monitoring host, and through the cooperation of the entire full-thread screw 104, the center point (sample test point) of each measurement is at the same height, ensuring the optimal laser ablation height of the sample 4 and a good sample ablation effect.

[0031] The sample 4 is placed on a sample support 201 provided on the sample stand 2. The upper surface of the sample support 201 is covered with a plastic-sprayed steel plate or a plastic-sprayed aluminum alloy plate. The bottom of the sample support 201 is installed on a turntable. The turntable is connected to a rotating motor 202, which is used to control the rotation of the sample support 201 to adjust the detection position of the sample 4 through the rotating motor 202. The bottom of the rotating motor 202 is installed on a motor fixing plate 203. The bottom of the motor fixing plate 203 is installed on the top of the cylinder rod of the lifting cylinder 204. The bottom of the lifting cylinder 204 is fixed on a moving base 212, which is used for the lifting cylinder 204 to control the lifting of the sample support 201. A plurality of moving wheels 213 with a brake structure are installed at the bottom of the moving base 212, which are used to control the movement of the sample stand 2 and fix the position of the sample stand 2 through a brake device.

[0032] There are splints 205 on both sides of the sample support 201 for stably fixing the sample 4. The sample support 201 adopts a hollow structure. Two splint motors 206 are staggered inside the sample support 201. The splint motor 206 is connected to the lead screw 207. The other end of the lead screw 207 is installed on the side wall of the sample support 201 through a bearing 209. A nut seat 208 is threaded on the lead screw 207. The upper part of the nut seat 208 is connected to a splint support rod 210. The splint support rod 210 passes through a slide groove provided on the sample support 201. The top of the splint support rod 210 is connected to the splint 205, and the splint motor 206 is used to drive the lead screw 207 to rotate forward and reverse, and drive the nut seat 208 and the splint support rod 210 to move in the slide groove, thereby controlling the movement of the splint 205.

[0033] The splint motor 206, the rotating motor 202 and the lifting cylinder 204 are all electrically connected to the electric control box 211, which is installed on the mobile base 212. A controller is provided in the electric control box 211, and the controller controls the operation of the above-mentioned driving components by controlling the on and off of the relay.

[0034] A method for operating a flexible laser ablation cell comprises the following steps:

[0035] 1) Mark the test point on the sample 4 to be tested, place the sample 4 to be tested on the sample support 201, control the clamping plate motor 206 through the control button in the electric control box 211, so that the clamping plates 205 on both sides clamp or support the fixed sample 4, push the sample stand 2 to the bottom of the flexible erosion pool 1 through the moving wheel 213, control the lifting and lowering of the lifting cylinder 204 through the control button in the electric control box 211, control the sample 4 to contact the bottom of the TPR cover 101, and then control the rotating motor 202 to make the center of the position to be tested of the sample 4 located inside the TPR cover 101;

[0036] 2) The image of the test point of the sample 4 is monitored by the monitoring host, and the sample 4 is fine-tuned through the operation steps in step 1 so that the marking point is located at the center of the image, that is, the marking point is located at the irradiation point of the laser beam 302, and the monitoring host records the position of the focal length of the fixed-point monitoring camera;

[0037] 3) The upper fixing nut 105 and the lower fixing nut 106 are adjusted at the concave part of the surface of the sample 4, so that the bottom of the TPR cover 101 is pushed downward into the concave part. Similarly, the upper fixing nut 105 and the lower fixing nut 106 are adjusted at the convex part of the surface of the sample 4, so that the bottom of the TPR cover 101 is lifted upward and closely attached to the convex part.

[0038] 4) After carefully adjusting the TPR cover 101, fill the small gap between the sample and the TPR cover 101 with plasticine to form a closed cavity 207 between the TPR cover 101 and the sample 4, then turn on the laser transmitter 301, so that the laser beam 302 enters the closed cavity 207 through the observation window 110 and hits the sample 4, and the sample is analyzed by the LA-MC-ICPMS device or the LA-IR-ICPMS device;

[0039] 5) After one detection of sample 4 is completed, the rotation and movement of sample 4 are controlled by the lifting cylinder 204, the rotating motor 202 and the moving wheel 213, the next detection point on sample 4 is selected, and according to the position of the focal length of the fixed-point monitoring camera recorded by the monitoring host, the height of the point to be tested of sample 4 in the flexible erosion tank 1 is adjusted to make the height of each detection point consistent, that is, the height of the laser beam 302 irradiated on the sample 4 is consistent, and steps 1-4 are repeated to perform sample detection and analysis.

[0040] The present invention is not limited to the above-mentioned implementation modes, and anyone should be aware of the structural changes made under the enlightenment of the present invention, and all those having the same or similar technical solutions as the present invention fall within the protection scope of the present invention.

[0041] The techniques, shapes, and structural parts not described in detail in the present invention are all well-known techniques.

Claims

1. A flexible laser ablation cell, characterized in that: It includes a laser system, a flexible ablation pool and a sample stand. The flexible ablation pool is provided with a TPR cover. The top of the TPR cover is connected to an upper support plate. The lower periphery of the TPR cover is connected to a lower fixed flexible ring for supporting and fixing the TPR cover. A plurality of full-thread screws are connected between the upper support plate and the lower fixed flexible ring. The full-thread screws adjust the height of the bottom of the TPR cover through a fixing nut. The bottom of the TPR cover is attached and sealed to the sample surface. A closed cavity is formed between the TPR cover and the sample. The plane of the sample detection part becomes the base of the flexible ablation pool. An observation window is provided in the middle of the upper support plate, and calcium fluoride glass is installed in the observation window. The laser beam of the laser system enters the closed cavity through the calcium fluoride glass. The laser beam is emitted by a laser emitter provided in the laser system. The laser system is fixed together with the flexible ablation pool, and the laser beam is used to irradiate the bottom center position of the flexible ablation pool; The lower fixed flexible ring is provided with a threaded hole adapted to the full-thread screw, which is used to fix the bottom of the full-thread screw to the lower fixed flexible ring. A through hole is provided at a relative position between the upper support plate and the lower fixed flexible ring, and the upper part of the full-thread screw passes through the through hole. An upper fixing nut and a lower fixing nut are respectively provided on the full-thread screw and above and below the upper support plate, which are used to control the distance between the upper support plate and the lower fixed flexible ring on each side by adjusting the upper fixing nut and the lower fixing nut; The sample is placed on a sample support provided on the sample stand. Clamps are provided on both sides of the sample support for stably fixing the sample. The bottom of the sample support is connected to a rotating motor through a turntable. The bottom of the rotating motor is connected to a lifting cylinder for controlling the rotation and lifting of the sample support.

2. The flexible laser ablation cell according to claim 1, characterized in that: A monitoring bracket is installed on the upper support plate and at the observation window, and a fixed-point monitoring camera is installed on the monitoring bracket. The fixed-point monitoring camera is connected to the monitoring host for imaging. The fixed-point monitoring camera is focused at the center position of the bottom of the flexible erosion pool irradiated by the laser beam, and is used to fine-tune the measured point on the sample to coincide with the laser beam irradiation point.

3. The flexible laser ablation cell according to claim 1, characterized in that: The TPR housing is also provided with an air inlet and an air outlet for controlling the inlet and outlet of carrier gas.

4. The flexible laser ablation cell according to claim 1, characterized in that: The upper surface of the sample support is covered with a plastic-sprayed steel plate or a plastic-sprayed aluminum alloy plate, and the bottom of the sample support is installed on a turntable, which is connected to a rotating motor for controlling the rotation of the sample support to adjust the sample detection position through the rotating motor. The bottom of the rotating motor is installed on a motor fixing plate, and the bottom of the motor fixing plate is installed on the top of the cylinder rod of the lifting cylinder. The bottom of the lifting cylinder is fixed on a moving base, and the lifting cylinder is used to control the lifting of the sample support. A plurality of moving wheels with a brake structure are installed at the bottom of the moving base.

5. The flexible laser ablation cell according to claim 4, characterized in that: The sample support adopts a hollow structure, and two splint motors are staggered inside the sample support. The splint motor is connected to a lead screw, and the other end of the lead screw is installed on the side wall of the sample support through a bearing. A nut seat is threaded on the lead screw, and the upper part of the nut seat is connected to a splint support rod. The splint support rod passes through a slide groove provided on the sample support, and the top of the splint support rod is connected to a splint, which is used for the splint motor to control the movement of the splint through the lead screw and the nut seat.

6. The flexible laser ablation cell according to claim 5, characterized in that: The clamping plate motor, the rotating motor and the lifting cylinder are all electrically connected to an electric control box, and the electric control box is installed on the mobile base.

7. The working method of the flexible laser ablation cell according to any one of claims 1 to 6, characterized in that: The following steps are involved: 1) Mark the test point on the sample to be tested, place the sample to be tested on the sample support, control the clamping plate motor through the control button in the electric control box, so that the clamping plates on both sides clamp or support the fixed sample, push the sample stand to the bottom of the flexible erosion pool through the moving wheel, control the lifting cylinder through the control button in the electric control box, control the sample to contact the bottom of the TPR cover, and then control the rotating motor to make the marked point on the sample to be tested located inside the TPR cover; 2) Monitor the image of the test point of the sample to be tested through the monitoring host, and fine-tune the sample to be tested through the operation steps in step 1 so that the marked point is located at the center of the image, that is, the marked point is located at the irradiation point of the laser beam, and the monitoring host records the position of the focal length of the fixed-point monitoring camera; 3) For the concave part of the sample surface, adjust the upper fixing nut and the lower fixing nut here so that the bottom of the TPR cover goes down to the concave part. Similarly, for the convex part of the sample surface, adjust the upper fixing nut and the lower fixing nut here so that the bottom of the TPR cover is lifted up and close to the convex part. 4) After carefully adjusting the TPR cover, fill the small gap between the sample and the TPR cover with plasticine to form a closed cavity between the TPR cover and the sample, then turn on the laser transmitter to allow the laser beam to enter the closed cavity through the observation window and hit the sample, and then analyze the sample using the LA-MC-ICPMS device or LA-IR-ICPMS device; 5) After the detection of one sample is completed, the rotation and movement of the sample are controlled by the lifting cylinder, rotating motor and moving wheel, and the next point to be tested on the sample is selected. According to the position of the focal length of the fixed-point monitoring camera recorded by the monitoring host, the height of the sample's point to be tested in the flexible ablation tank is adjusted to make the height of each detection point consistent, that is, the height of the laser beam irradiated on the sample is consistent, and steps 1-4 are repeated for sample detection and analysis.

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