A detection system combining moisture determination and laser induced breakdown spectroscopy

Abstract

The present invention relates to the field of object component detection, and discloses a water content determination and laser induced breakdown spectroscopy combined detection system, including a housing, an optical focusing unit, an optical probe, a heating component, an electronic balance, a lifting unit and a negative pressure exhaust unit. The housing is provided with a detection cavity, the detection cavity has a placement port, an irradiation port and a signal port, the electronic balance and the heating component are arranged in the detection cavity, the electronic balance is provided with a tray, the lifting unit is arranged below the tray to support the tray away from the electronic balance; the optical focusing unit has a first output end, the first output end faces the tray through the irradiation port, the optical probe has a second output end, the second output end faces the tray, the negative pressure exhaust unit is connected to the detection cavity, and the placement port is provided with a door. The beneficial effect is that the present invention can simplify the detection operation process, complete the water content and component measurement in one instrument, avoid the system error caused by moving between multiple instruments, and expand the versatility and convenience of LIBS.

Description

Technical Field

[0001] The invention relates to the field of object component detection, and in particular to a water content determination and laser induced breakdown spectroscopy combined detection system. Background Art

[0002] At present, LIBS is the abbreviation of Laser-Induced Breakdown Spectroscopy. This technology uses ultrashort pulse laser to focus on the sample surface to form plasma, and uses a spectrometer to analyze the plasma emission spectrum to identify the elemental composition of the sample, and then can identify, classify, qualitatively and quantitatively analyze the material.

[0003] The relevant technologies have the following three bottleneck problems: 1) The method of combining a single device with a spectrum-mass spectrometer does not have the ability to directly measure the moisture content of solid samples; 2) The method of combining a single device with machine learning prediction is highly dependent on the amount of historical data, and it is difficult to form a clear linear relationship between the spectrum and the results, which makes the results only valid within a single machine and difficult to achieve horizontal comparison of data from different companies. 3) The method of combining another industrial analysis device or another independent component for analysis involves two different physical systems, which takes up a large space, requires multiple movements of the sample, and the system and operation control are relatively complex. Summary of the invention

[0004] The technical problem to be solved by the present invention is that a single device combined with a spectrum-mass spectrometry method does not have the ability to directly measure the moisture content of a solid sample, requires the sample to be moved multiple times, and the system and operation control are relatively complex.

[0005] In order to solve the above technical problems, the present invention provides a moisture determination and laser induced breakdown spectroscopy combined detection system, including a shell, an optical focusing unit, an optical probe, a heating component, an electronic balance, a lifting unit and a negative pressure exhaust unit, the shell is provided with a detection cavity, the detection cavity has a placement port, an irradiation port and a signal port, the electronic balance and the heating component are both arranged in the detection cavity, the electronic balance is provided with a tray, the lifting unit is arranged below the tray to be able to support the tray away from the electronic balance; the optical focusing unit has a first output end, the first output end is toward the tray through the irradiation port, the optical probe has a second output end, the second output end is toward the tray through the signal port, the negative pressure exhaust unit is connected to the detection cavity, and the placement port is provided with a door.

[0006] In the above technical solution, the heating component includes a halogen lamp, and the halogen lamp faces the tray.

[0007] In the above technical solution, the halogen lamps are connected end to end to form a through hole, and the through hole is arranged on the same line as the irradiation port.

[0008] In the above technical solution, the lifting unit includes a push rod and a support plate, the push rod connects the shell and the support plate, and the support plate is arranged below the tray.

[0009] In the above technical solution, the support plate is provided with a through hole, the cross-sectional area of ​​the through hole is smaller than the cross-sectional area of ​​the tray, the extension direction of the push rod is collinear with the direction of the first output end, and the balance and the tray are respectively located on both sides of the through hole.

[0010] In the above technical solution, there are two push rods, which are symmetrically arranged on both sides of the support plate.

[0011] In the above technical solution, it also includes an exhaust pipe, the shell is provided with an exhaust port connected to the detection cavity, and the exhaust pipe is connected to the exhaust port and the negative pressure exhaust unit.

[0012] In the above technical solution, it also includes a temperature probe, which is arranged in the detection cavity.

[0013] In the above technical solution, the signal port is arranged at one side of the detection cavity, and the direction of the second output end forms an angle with the direction of the first output end.

[0014] Compared with the prior art, the moisture determination and laser induced breakdown spectroscopy combined detection system of the embodiment of the present invention has the following beneficial effects: an optical focusing unit, an optical probe, a heating component, an electronic balance, a lifting unit and a negative pressure exhaust unit are arranged in the detection chamber, which can complete the moisture determination and laser induced breakdown spectroscopy detection of the same sample without moving the sample multiple times; the tray can be used to place the sample, which is convenient for other instruments to process the sample; the heating component can quickly dry the sample, and the negative pressure exhaust unit can timely remove the moisture in the detection chamber to improve the accuracy of the moisture weight loss data measured by the electronic balance; the electronic balance often lifts or lowers the sample due to the change in the weight of the sample, and the lifting unit can keep the sample in a relatively stable state by supporting the tray, avoiding the sample from rising or lowering due to the weight change, which is beneficial for the optical probe and the focusing unit to focus on the sample to complete the composition measurement of the sample.

[0015] In summary, the present invention can simplify the detection operation process, complete the moisture determination and component measurement in the same instrument without significantly moving the sample, avoid the system error caused by moving between multiple instruments, and expand the versatility and convenience of LIBS. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 2 is a schematic diagram of the structure of a water content determination and laser induced breakdown spectroscopy combined detection system according to an embodiment of the present invention;

[0017] Figure 2 It is a schematic diagram of the structure decomposition of the electronic balance and the tray of an embodiment of the present invention;

[0018] In the figure, 2, optical focusing unit; 3, sample; 5, optical probe; 6, halogen lamp; 7, tray; 8, support plate; 9, push rod; 10, electronic balance; 11, housing; 12, door; 13, temperature probe; 14, exhaust port; 15, exhaust pipe; 16, negative pressure exhaust unit. DETAILED DESCRIPTION

[0019] The specific implementation of the present invention is further described in detail below in conjunction with the accompanying drawings and examples. The following examples are used to illustrate the present invention, but are not intended to limit the scope of the present invention.

[0020] In the description of the present invention, it should be understood that the terms "up", "down", "left", "right", "inside", "outside", etc. used in the present invention to indicate the orientation or position relationship are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0021] In the description of the present invention, it should be understood that the terms "connected", "connected", "fixed" and the like used in the present invention should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or a welding connection; it can be directly connected or indirectly connected through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements, unless otherwise clearly defined. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0022] If the first and second are described, they are only used to distinguish the technical features and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the sequence of the indicated technical features.

[0023] like Figure 1 and Figure 2As shown, a moisture determination and laser induced breakdown spectroscopy combined detection system according to a preferred embodiment of the present invention comprises a housing 11, an optical focusing unit 2, an optical probe 5, a heating assembly, an electronic balance 10, a lifting unit and a negative pressure exhaust unit 16, wherein the housing 11 is provided with a detection cavity, the detection cavity has a placement port, an irradiation port and a signal port, the electronic balance 10 and the heating assembly are both arranged in the detection cavity, the electronic balance 10 is provided with a tray 7, the lifting unit is arranged below the tray 7 to be able to support the tray 7 away from the electronic balance 10; the optical focusing unit 2 has a first output end, the first output end is directed toward the tray 7 through the irradiation port, the optical probe 5 has a second output end, the second output end is directed toward the tray 7 through the signal port, the negative pressure exhaust unit 16 is connected to the detection cavity, and the placement port is provided with a door 12.

[0024] It can be understood that the detection chamber is provided with an optical focusing unit 2, an optical probe 5, a heating component, an electronic balance 10, a lifting unit and a negative pressure exhaust unit 16, which can complete the moisture determination and laser induced breakdown spectroscopy detection of the same sample 3 without moving the sample 3 multiple times; the tray 7 can place the sample 3, which is convenient for other instruments to process the sample 3; the heating component can quickly dry the sample 3, and the negative pressure exhaust unit 16 can timely remove the moisture in the detection chamber to improve the accuracy of the moisture weight loss data measured by the electronic balance 10; the electronic balance 10 often lifts or lowers the sample 3 due to the change in the weight of the sample 3. The lifting unit can keep the sample 3 in a relatively stable state by supporting the tray 7, avoiding the sample 3 from rising or lowering due to the weight change, which is beneficial for the optical probe 5 optics and the focusing unit to focus on the sample 3 to complete the composition measurement of the sample 3.

[0025] In addition, the placement opening can be used for placing the sample 3 into the detection chamber, and the door 12 can close the placement opening to improve the sealing performance of the detection chamber.

[0026] To improve the accuracy of the experiment, sample 3 is a powdered tablet or a relatively flat solid block, which can be dry or wet. The height is within 10 mm when placed, and absorbent filter paper is used to touch and remove visible water stains on the surface. The weight is controlled within 20 g. The block sample 3 needs to have relatively flat upper and lower surfaces, and the bottom must be placed stably.

[0027] like Figure 2 As shown, specifically, the bottom of the tray 7 has a protruding structure, which is not limited to a conical shape, and is used to connect and fix the weight sensor of the electronic balance 10. The material of the tray 7 is not limited to Teflon material or metal material. Specifically, before the test, sulfuric acid paper or other weighing paper is preferably placed on the tray 7 and peeled and zeroed for calibration.

[0028] Accordingly, the electronic balance 10 has a structure matching the protruding structure, so that the support plate 8 can be fixed on the electronic balance 10, preferably but not limited to a conical shape. The electronic balance 10 can be customized and modified from a conventional electronic balance 10, and the bottom has a leveling capability.

[0029] like Figure 1 As shown, further, the heating component includes a halogen lamp 6 , and the halogen lamp 6 faces the tray 7 .

[0030] It is understood that the halogen lamp 6 has high thermal efficiency and can quickly dry the sample 3 to improve the accuracy of the water weight loss data. The halogen lamp 6 is preferably a halogen infrared lamp source with a power of not less than 300W, and the maximum width of the lamp tube must be less than the width of the openable and closable operating door 12.

[0031] like Figure 1 As shown, further, the halogen lamps 6 are connected end to end to form a through hole, and the through hole is arranged on the same line as the irradiation port.

[0032] It can be understood that the halogen lamps 6 are connected end to end to form a through hole, which is beneficial for the light beam to pass through the irradiation hole and can also make the sample 3 evenly heated during the heating process of the sample 3.

[0033] Furthermore, the lifting unit includes a push rod 9 and a support plate 8 , wherein the push rod 9 connects the housing 11 and the support plate 8 , and the support plate 8 is disposed below the tray 7 .

[0034] Furthermore, the support plate 8 is provided with a through hole, the cross-sectional area of ​​the through hole is smaller than the cross-sectional area of ​​the tray 7, the extension direction of the push rod 9 is collinear with the direction of the first output end, and the balance and the tray 7 are respectively located on both sides of the through hole.

[0035] It can be understood that the hole allows the weight sensor of the electronic balance 10 to pass through on the one hand, and on the other hand, it can prevent the support plate 8 from interfering with the tray 7 and affecting the determination result and the accuracy of the measurement result when the electronic balance 10 drives the tray 7 to rise and fall.

[0036] Preferably, the material of the support plate 8 includes, but is not limited to, Teflon and metal, and can withstand heat up to 50°C without deformation. The shape of the support plate 8 is preferably an oblate cylinder, and the top surface of the support plate 8 is preferably treated as a non-smooth surface with a certain anti-slip effect. The bottom surface of the support plate 8 is preferably connected to the push rod 9 at least four circumferentially arranged fixed points.

[0037] Specifically, the push rod 9 can be an electric push rod 9 or a hydraulic push rod 9, the bottom of which is fixed to the inner side of the bottom of the detection space shell 11, preferably fixed by a snap; the top is connected to the fixed point below the support plate 8, preferably a soft connection.

[0038] Preferably, there are two push rods 9 symmetrically arranged on both sides of the support plate 8 .

[0039] Furthermore, it also includes an exhaust pipe 15 . The housing 11 is provided with an exhaust port 14 connected to the detection chamber. The exhaust pipe 15 connects the exhaust port 14 and the negative pressure exhaust unit 16 .

[0040] It is understandable that the negative pressure exhaust unit 16 provides negative pressure to the exhaust port 14 through the exhaust hose, so as to extract evaporated water during rapid drying and to extract floating particles in the detection space during component analysis.

[0041] Furthermore, it also includes a temperature probe 13, which is arranged in the detection cavity. The temperature probe 13 can detect the temperature in the detection cavity.

[0042] Furthermore, the signal port is arranged at one side of the detection cavity, and the direction of the second output end forms an angle with the direction of the first output end.

[0043] In one embodiment, the moisture determination process of the present invention is: adjust the lifting unit to lower the support plate 8 to a safe position where it does not contact the tray 7; open the operating door 12, and place the sulfuric acid paper or other anti-fouling pad used to pad the sample 3 on the tray 7; close the operating door 12, and perform data peeling operation on the electronic balance 10; open the operating door 12 after zeroing, carefully move in the sample 3, and close the operating door 12; the electronic balance 10 records the starting weight W1; start the heating component and the negative pressure exhaust unit 16, and the temperature probe 13 maintains real-time temperature monitoring. By adjusting the power of the heating component and the power of the negative pressure exhaust unit 16, the overall temperature of the detection chamber is controlled to be constant at 40°C or higher; when the data recorded by the electronic balance 10 no longer decreases, record the end weight W2; the received basis moisture content of the sample 3 is (W2-W1) / W1, and the sample 3 can be regarded as an air-dry basis state at this time; after the recording is completed, turn off the heating component but keep the negative pressure exhaust unit 16 turned on.

[0044] The laser induced breakdown spectroscopy detection process of the present invention is: adjust the lifting unit to raise the support plate 8, and then lift the tray 7 to a stable position that does not contact the electronic balance 10, and the position is lower than the intersection of the optical axes of the optical focusing unit 2 and the optical probe 5; turn on the optical focusing unit 2, so that the non-laser focusing light beam is irradiated to the surface of the sample 3, and the height of the lifting unit is fixed when the minimum spot is reached to complete the optical focusing; the optical focusing unit 2 is switched to a pulsed laser, and the surface of the sample 3 is started to be detected and irradiated, and the optical probe 5 continues to collect the spectral signal of the sample 3; after the detection is completed, turn off the pulsed laser, open the operating door 12, and take the sample 3 together with the padding paper from the tray 7 to enter the next detection, or close the operating door 12 and the negative pressure exhaust unit 16 to stop the detection.

[0045] In summary, the embodiment of the present invention provides a moisture determination and laser induced breakdown spectroscopy combined detection system, in which an optical focusing unit 2, an optical probe 5, a heating component, an electronic balance 10, a lifting unit and a negative pressure exhaust unit 16 are arranged in the detection chamber, which can complete the moisture determination and laser induced breakdown spectroscopy detection of the same sample 3, without the need to move the sample 3 multiple times; the tray 7 can place the sample 3, which is convenient for other instruments to process the sample 3; the heating component can quickly dry the sample 3, and the negative pressure exhaust unit 16 can timely remove the moisture in the detection chamber to improve the accuracy of the moisture weight loss data measured by the electronic balance 10; the electronic balance 10 often lifts or lowers the sample 3 due to the change in the weight of the sample 3, and the lifting unit can keep the sample 3 in a relatively stable state by supporting the tray 7, avoiding the sample 3 from rising or falling due to the weight change, which is beneficial for the optical probe 5 and the focusing unit to focus on the sample 3 to complete the composition measurement of the sample 3.

[0046] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and substitutions can be made without departing from the technical principles of the present invention. These improvements and substitutions should also be regarded as the scope of protection of the present invention.

Claims

1. A water content determination and laser induced breakdown spectroscopy combined detection system, characterized in that: The electronic device comprises a housing, an optical focusing unit, an optical probe, a heating component, an electronic balance, a lifting unit and a negative pressure exhaust unit, wherein the housing is provided with a detection cavity, the detection cavity has a placement port, an irradiation port and a signal port, the electronic balance and the heating component are both arranged in the detection cavity, the electronic balance is provided with a tray, the lifting unit is arranged below the tray so as to support the tray away from the electronic balance; the optical focusing unit has a first output end, the first output end is directed toward the tray through the irradiation port, the optical probe has a second output end, the second output end is directed toward the tray through the signal port, the negative pressure exhaust unit is communicated with the detection cavity, and the placement port is provided with a door; The lifting unit includes a push rod and a support plate, wherein the push rod connects the housing and the support plate, and the support plate is disposed below the tray; The support plate is provided with a through hole, the cross-sectional area of ​​the through hole is smaller than the cross-sectional area of ​​the tray, the extension direction of the push rod is collinear with the direction of the first output end, and the balance and the tray are respectively located on both sides of the through hole; It also includes an exhaust pipe, the shell is provided with an exhaust port connected to the detection cavity, and the exhaust pipe is connected to the exhaust port and the negative pressure exhaust unit.

2. The moisture determination and laser induced breakdown spectroscopy combined detection system according to claim 1 is characterized in that: The heating assembly includes a halogen lamp directed toward the tray.

3. The moisture determination and laser induced breakdown spectroscopy combined detection system according to claim 2 is characterized in that: The halogen lamps are connected end to end to form a through hole, and the through hole is arranged on the same line as the irradiation port.

4. The moisture determination and laser induced breakdown spectroscopy combined detection system according to claim 1 is characterized in that: The number of the push rods is two, which are symmetrically arranged on both sides of the support plate.

5. The moisture determination and laser induced breakdown spectroscopy combined detection system according to claim 1 is characterized in that: It also includes a temperature probe, which is arranged in the detection cavity.

6. The water content determination and laser induced breakdown spectroscopy combined detection system according to any one of claims 1 to 5, characterized in that: The signal port is arranged at one side of the detection cavity, and the direction of the second output end forms an angle with the direction of the first output end.

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