Chloride ion detection method based on machine vision
By detecting chloride ions on lead-halide perovskite quantum dot fluorescence detection test strips and analyzing images using machine vision technology, the complex and unreal-time problems of existing chloride ion detection technology are solved, and efficient, accurate and portable chloride ion detection is achieved.
Patent Information
- Application Number
- CN202510010209.4
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-03
- Publication Date
- 2025-03-28
AI Technical Summary
The existing chloride ion detection technology has the problems of complex operation, expensive equipment, and inability to detect real-time on-site, making it difficult to meet the simple, portable and cost-effective detection needs.
Using a machine vision-based detection method, a chlorine-containing solution or gas is added to a fluorescence detection test strip of lead-halogen perovskite quantum dots, resulting in color changes. An industrial camera is used to capture images and calculate the chloride ion concentration through an image processing algorithm.
It improves detection sensitivity and accuracy, realizes automation and real-time analysis, simplifies operations, is suitable for rapid on-site inspection, and has important ecological protection significance.
Smart Images
Figure CN119715488A_ABST
Abstract
Description
Technical Field
[0001] The invention relates to a chloride ion detection method based on machine vision. Background Art
[0002] Chloride ions are widely present in water, often in the form of chloride salts such as sodium chloride, calcium chloride, potassium chloride, and magnesium chloride. However, high concentrations of chloride ions can corrode metal pipe equipment and release toxic metal substances from pipe fittings. At the same time, higher concentrations of chloride ions can cause vegetation, microorganisms, etc. to dehydrate and die. Therefore, it is necessary to monitor the concentration level of chloride ions in water. So far, the chlorine measurement techniques that have been reported and used mainly include titration, spectrophotometry, ion chromatography, electrochemical methods, etc. Although these techniques have high accuracy and precision, they involve expensive instruments, complex operations, complex wastewater pretreatment, high water quality requirements, and cannot be detected on site in real time. Therefore, it is necessary to find simple, portable and cost-effective methods and devices for detecting chloride ions in water. Summary of the invention
[0003] The present invention provides a chloride ion detection method based on machine vision in order to solve the problems existing in the above-mentioned prior art.
[0004] The technical solutions adopted in the present invention are: A method for detecting chloride ions based on machine vision comprises the following steps: 1) Adding a chlorine-containing solution or a chlorine-containing gas to a fluorescent test paper having lead halide perovskite quantum dots to obtain a color-changing test paper; 2) Take a picture of the test paper, obtain the fluorescence color change area data, and calculate the chloride ion concentration based on the color change area data.
[0005] Furthermore, the preparation method of the lead halide perovskite quantum dots is: 1) Cs 2 CO 3 , oleic acid and octadecene were heated under vacuum until Cs 2 CO 3 Completely dissolve to generate cesium oleate; then change the vacuum to nitrogen and remove impurity gases to obtain the precursor Cs-OA solution, transfer the Cs-OA solution to a glass sample bottle for storage while hot, cool it to a solid state at room temperature, and heat it to melt when it is used; 2) PbBr 2 , octadecene, oleic acid and oleylamine were stirred and mixed, and then heated under vacuum to make PbBr 2 Completely dissolved; 3) Under nitrogen protection, use a syringe to absorb the pre-heated melted Cs-OA solution, and then mix it with the completely dissolved PbBr 2Stir to mix, then cool; 4) adding n-hexane and acetone solution to the cooled solution, discarding the supernatant after centrifugation, and obtaining a solid after centrifugation; 5) The solid after centrifugation is dissolved in n-hexane to obtain a lead halide perovskite quantum dot solution.
[0006] Furthermore, the preparation method of the test paper is: diluting the concentration of the lead halide perovskite quantum dot solution to 0.1-0.3 mg / mL, evenly distributing the diluted lead halide perovskite quantum dot solution on the filter paper, and drying it.
[0007] Furthermore, in step 1), Cs 2 CO 3 The addition amount of oleic acid and octadecene is: 1~2 g Cs 2 CO 3 , 3~6 mL oleic acid, 10~20 mL octadecene.
[0008] Furthermore, in step 2), PbBr 2 , octadecene, oleic acid and oleylamine are added in an amount of: 0.1~0.2g PbBr 2 , 10~20 mL octadecene, 0.5~1.5 mL oleic acid, 0.5~1.5 mL oleylamine.
[0009] Furthermore, in step 2), a luminescent metal compound is also added. After the luminescent metal compound is added, step 5) finally obtains a lead halide perovskite quantum dot solution doped with a luminescent metal element.
[0010] Furthermore, the added amount of the luminescent metal compound is: 0.01~0.05g; the luminescent metal compound is: one or more of: manganese bromide, europium oxide, cerium oxide, terbium bromide, and antimony oxide.
[0011] Furthermore, the process of calculating the chloride ion concentration based on the test paper photo is as follows: S1: Perform linear fitting on the prepared standard curve to obtain the relationship between the color change area value and the chloride ion concentration; S2: Use an industrial camera to photograph the test paper to obtain an image of the test paper; S3: grayscale, denoise and enhance the acquired image; S4: using an image processing algorithm to analyze the color change region of the test paper in the image, and calculating the color change area value of the region; S5: According to the relationship fitted in step S1, the calculated color change area value is input into the relationship to obtain the corresponding chloride ion concentration value; S6: The detected chloride ion concentration is displayed through the IPS touch screen, and the relevant concentration trend and historical data analysis are provided.
[0012] Further, in S1, the relationship between the color change area value and the chloride ion concentration is obtained by the following steps: S11: preparing solutions of chloride ion concentrations of different concentrations, and dropping them onto a fluorescent test paper of lead halide perovskite quantum dots to obtain a test paper with color change; S12: Use ultraviolet light with a wavelength of 365nm to illuminate the test paper to stimulate the color that can be captured by the industrial camera; S13: Using an industrial camera to photograph the test paper after excitation, and obtaining an image of the color change area on the surface of the test paper; S14: Performing color analysis on the captured image, calculating the area value of the color change region, and recording the color change area values corresponding to solutions with different chloride ion concentrations; S15: Linearly fit the color change area values under different concentrations of chloride ion solutions with the corresponding chloride ion concentrations to obtain a relationship between the color change area value and the chloride ion concentration, and write the relationship into the program for subsequent detection.
[0013] Furthermore, in S4, the process of analyzing the color change area by the image processing algorithm is as follows: Use image threshold segmentation method to separate the color change area from the background; Use the Canny edge detection algorithm to extract the contours of the color change area; The calculation process of the color change area value of the color change area is: According to the outline of the extracted color change area, count the number of pixels it contains; The actual area value of the color change area is obtained by multiplying the number of pixels by the unit area.
[0014] The present invention has the following beneficial effects: 1) The present invention significantly improves the detection sensitivity by combining the lead halide perovskite quantum dot fluorescence detection paper with an industrial camera. The area of color change can accurately reflect the subtle changes in chloride ion concentration with high accuracy.
[0015] 2) The device of the present invention analyzes the image data collected by the industrial camera in real time through the main controller, automatically calculates the chloride ion concentration and displays the result, eliminating the tedious steps of manual analysis and greatly improving the detection efficiency.
[0016] 3) The detection of chloride ions in wastewater of the present invention can be used in the fields of environmental monitoring, water quality analysis, etc., and is of great significance to ecological protection.
[0017] 4) The present invention is simple to operate, convenient to carry, and can be used for on-site rapid detection. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] Figure 1 It is a schematic structural diagram of the detection device of the present invention.
[0019] Figure 2 It is a structural schematic diagram of the detection device of the present invention from another viewing angle.
[0020] Figure 3 Fluorescence spectrum of lead halide perovskite quantum dot test paper under excitation from 450 nm to 600 nm.
[0021] Lead halide perovskite quantum dots after adding different concentrations of chloride ions: ( Figure 4a )Fluorescence spectrum;( Figure 4b ) Image under ultraviolet light corresponding to the concentration relationship of chloride ion detection.
[0022] Figure 5 Fluorescent quantum dots doped with rare metal elements, lead halide perovskite quantum dots, react with chloride ion aqueous solution. DETAILED DESCRIPTION
[0023] The present invention will be further described below in conjunction with the accompanying drawings. Example 1
[0024] like Figure 1 and Figure 2 The hardware equipment of the present invention includes: a rack 1, an IPS touch screen 2, an industrial camera 3, an LED white light bar 4, an ultraviolet light bar 5, a testing table 6 and a main controller. The IPS touch screen 2, the industrial camera 3, the LED light bar 4, and the ultraviolet light bar 5 are all electrically connected to the main controller (not shown in the figure).
[0025] The industrial camera 3 is used to collect the color change area change value presented by the chloride ion concentration of the wastewater to be tested and transmit it back to the main controller for processing, thereby obtaining the chloride ion concentration of the wastewater to be tested and displaying the result on the IPS touch screen 2.
[0026] The LED white light strip 4 and the ultraviolet light strip 5 are arranged on the upper side of the frame 1 to provide a stable light source and brightness, wherein the wavelength of the ultraviolet light strip 5 is 220-380nm, and the detection table 6 is a platform with a square depression in the center for placing the test paper.
[0027] The main controller uses an AI artificial intelligence development board, which has powerful image processing capabilities and deep learning algorithm support. It is used to process the image data collected by the industrial camera 3 in real time and perform color change area analysis and chloride ion concentration detection. The development board uses GPU acceleration to achieve efficient image processing and data calculation, ensuring the real-time and accuracy of the system.
[0028] The IPS touch screen 2 is used to display the chloride ion concentration value of the wastewater to be tested, and has a human-computer interaction function, allowing the user to input relevant parameters and set them. The IPS touch screen 2 interacts with the main controller through a graphical interface to display the chloride ion concentration change trend and historical data storage information in real time.
[0029] The industrial camera 3 is a CMOS camera with high resolution and high speed acquisition performance, and is used to collect the image data of the tested paper in real time. The collected image data is processed and analyzed by the master controller to determine the color change area caused by the change in chloride ion concentration in the wastewater. Example 2
[0030] Preparation of lead halide perovskite quantum dot solution without luminescent metal elements: 1) Add 1.6291 g Cs into a 100 mL glass three-necked flask. 2 CO 3 , 5 mL OA and 15 mL ODE were heated at 150 °C under vacuum for about 1 h until Cs 2 CO 3 Completely dissolved to generate cesium oleate. Then, change the vacuum to nitrogen to remove the remaining impurity gas in the system. After 30 minutes, 20 mL of 0.5 mmol / mL Cs-OA solution can be obtained. Transfer the solution to a glass sample bottle while it is hot and store it. Cool it to a solid state at room temperature and heat it to 100 °C to melt it when it is used.
[0031] 2) Weigh 0.1468 g of lead bromide (PbBr 2 ), pipette 15 mL of octadecene (ODE), 1 mL of oleic acid (OA), and 1 mL of oleylamine (OAM) and mix them into a 100 mL three-necked flask, and put in a magnetic stirrer. First, evacuate for 30 min, then heat in a heating mantle at 120 °C under vacuum for 30 min to make PbBr 2 Completely dissolved.
[0032] 3) Under nitrogen protection, insert a thermometer into the three-necked flask in step 2) and, when it comes into contact with the solution in the flask, raise the temperature to 150°C. Use a syringe to draw 0.2 mL of the pre-heated and melted Cs-OA solution and immediately inject it into the flask. Stir for 5 s and then quickly transfer the solution out of the flask and cool it in an ice water bath.
[0033] 4) Add 10 mL of n-hexane and 15 mL of acetone solution to the cooled solution, centrifuge at 11,000 rpm, and discard the supernatant in the centrifuge tube.
[0034] 5) After centrifugation of the above solution, the solid was dissolved in n-hexane to obtain a 0.6 mg / mL solution without Glowing Gold Elemental Lead halide perovskite quantum dot solution.
[0035] The detection of lead halide perovskite quantum dots was expanded to prepare fluorescent detection test paper and the detection application of chloride ions was studied. The lead halide perovskite quantum dot solution was diluted to 0.1 mg / mL, and the cut filter paper (cellulose paper) was soaked to distribute the diluted lead halide perovskite quantum dots on the paper. After drying, the lead halide perovskite quantum dot fluorescent detection test paper with fluorescent emission was obtained. Figure 3 , Fluorescence spectrum of lead halide perovskite quantum dot test paper under excitation from 450 nm to 600 nm.
[0036] The difference between adding luminescent metal elements and not adding luminescent metal elements is that the color changes during detection are different. The undoped ones change from green to blue, while the doped ones change from orange-red to purple. Example 3
[0037] Preparation of lead halide perovskite quantum dot solution without luminescent metal elements: 1) Add 1.9467 g Cs into a 100 mL glass three-necked flask. 2 CO 3 , 6 mL OA and 20 mL ODE were heated at 160 °C under vacuum for about 0.75 h until Cs 2 CO 3 Completely dissolved to generate cesium oleate. Then, the vacuum was changed to nitrogen to remove the remaining impurity gas in the system, and 26 mL of 0.7 mmol / mL Cs-OA precursor solution was obtained. The solution was transferred to a glass sample bottle for storage while hot, cooled to solid at room temperature, and heated to melt before use.
[0038] 2) Weigh 1.9868 g of lead bromide (PbBr 2 ), pipette 20 mL of octadecene (ODE), 1.5 mL of oleic acid (OA), and 1.5 mL of oleylamine (OAM), mix and add into a 100 mL three-necked flask, and put in a magnetic stirrer, first evacuate for 60 min, then heat in a heating mantle at 160°C under vacuum for 60 min to make PbBr 2 Completely dissolved.
[0039] 3) Under nitrogen protection, insert the thermometer into the three-necked flask in step 2). When the temperature reaches 150-200 °C, use a syringe to absorb 0.2 mL of Cs-OA solution that has been heated and melted in advance, and immediately inject it into the flask. After stirring for 10 seconds, quickly transfer the solution out of the flask and cool it in an ice water bath.
[0040] 4) Add 10 mL of n-hexane and 15 mL of acetone solution to the cooled solution, centrifuge at 11,000 rpm, and discard the supernatant in the centrifuge tube.
[0041] 5) After centrifuging the above solution, the solid was dissolved in n-hexane to obtain a lead halide perovskite quantum dot solution without luminescent metal elements with a concentration of 1 mg / mL.
[0042] The detection of lead halide perovskite quantum dots was expanded to prepare fluorescent detection test paper and the detection application of chloride ions was studied. The lead halide perovskite quantum dot solution was diluted to 0.3 mg / mL, and the cut filter paper (cellulose paper) was soaked to distribute the diluted lead halide perovskite quantum dots on the paper. After drying, the lead halide perovskite quantum dot fluorescent detection test paper with fluorescent emission was obtained. Example 4
[0043] Preparation of lead halide perovskite quantum dot solution doped with luminescent metal elements 1) Add 1.2218 g Cs into a 100 mL glass three-necked flask. 2 CO 3 , 3 mL OA and 10 mL ODE were heated at 120 °C under vacuum for about 0.5 h until Cs 2 CO 3 Completely dissolved to generate cesium oleate. Then, change the vacuum to nitrogen to remove the remaining impurity gas in the system. After 60 minutes, 13 mL of 0.25 mmol / mL Cs-OA solution can be obtained. Transfer the solution to a glass sample bottle for storage while it is hot, cool it to a solid state at room temperature, and heat it to 100 °C to melt it when it is used. 2) Weigh 0.11101 g of lead bromide (PbBr 2 ), pipette 10 mL ODE, 0.5 mL OA, 0.5 mL OAM and 0.016 g luminescent metal compound, mix and add into a 100 mL three-necked flask, put in a magnetic stirrer, evacuate for 60 min, then heat in a heating mantle at 160 °C under vacuum for 60 min to make PbBr 2 Completely dissolved; 3) Under nitrogen protection, insert the thermometer into the three-necked flask in step 2) and touch the solution in the flask. When the temperature reaches 200°C, use a syringe to absorb 0.1 mL of the Cs-OA solution that has been heated and melted in advance, and immediately inject it into the flask. After stirring for 5 seconds, quickly transfer the solution out of the flask and cool it in an ice water bath. 4) Add 5 mL of n-hexane and 10 mL of acetone solution to the cooled solution, centrifuge at 11,000 rpm, and discard the supernatant in the centrifuge tube; 5) After centrifuging the above solution, the solid is dissolved in n-hexane to obtain a lead halide perovskite quantum dot solution doped with a luminescent metal element.
[0044] The detection of lead halide perovskite quantum dots was expanded to prepare fluorescent detection test paper and the detection application of chloride ions was studied. The lead halide perovskite quantum dot solution was diluted to 0.1 mg / mL, and the cut filter paper (cellulose paper) was soaked to distribute the diluted lead halide perovskite quantum dots on the paper. After drying, the lead halide perovskite quantum dot fluorescent detection test paper with fluorescent emission was obtained. Example 5
[0045] The process of detecting chloride ions by the lead halide perovskite quantum dot fluorescence test paper doped with luminescent metal elements is as follows: 1. Chloride ion detection method like Figure 5 When using the lead halide perovskite quantum dot fluorescence test paper to detect chloride ions, 3 to 5 drops of sample solution are added to the lead halide perovskite quantum dot fluorescence test paper or a gas containing chloride ions is passed to the lead halide perovskite quantum dot fluorescence test paper. When chloride ions are present in the solution, the color of the lead halide perovskite quantum dot fluorescence test paper changes significantly, and its fluorescence intensity or the area of color change varies with the concentration of chloride ions. When the test paper is irradiated with an ultraviolet lamp with a wavelength of 365nm, a fluorescent signal that can be captured by an industrial camera can be stimulated. The image of the color change area of the test paper is collected and analyzed by the machine vision system, and the concentration of chloride ions in the sample can be quickly and accurately calculated by combining the standard fitting curve of the color change area value and the chloride ion concentration. Therefore, the lead halide perovskite quantum dot fluorescence test paper can easily and quickly detect whether a sample has chloride ions.
[0046] 2. Chloride ion detection system based on machine vision equipment to detect chloride ions (1) Add 3 to 5 drops of chloride ion sample solution to the lead halide perovskite quantum dot fluorescence detection test paper, with a concentration gradient of chloride ions (6000 to 10000 ppm). After one minute, use clean filter paper to absorb the excess liquid on the surface of the test paper, and place the test paper under ultraviolet light; (2) Preparation of standard curve: Using a chloride ion detection system based on machine vision, place the test paper under ultraviolet light (365 nm). After turning on the equipment, the industrial camera takes a fluorescent image of the test paper. The collected image is processed by the main controller, including the identification of the color change area and the calculation of the area value. Figure 4a and Figure 4b, record the color change area value and the corresponding chloride ion concentration data under different concentration gradients (6000~10000ppm), and perform linear fitting on the data to generate a standard curve between the color change area value and the chloride ion concentration. Perform linear fitting on the prepared standard curve to obtain the relationship between the color change area value and the chloride ion concentration. The fitting formula is: y=3382.68x-2090.67 (x is the color change area value, y is the chloride ion concentration).
[0047] The fitted standard curve is stored in the equipment program for subsequent concentration detection of samples. The detection limit of the equipment is 100ppm.
[0048] (3) Sample testing The chloride ion sample solution to be tested is treated according to the above steps, and then dripped onto the lead halide perovskite quantum dot fluorescence detection test paper. After standing for one minute, the excess liquid on the surface is absorbed with filter paper, and the test paper is placed under ultraviolet light (365 nm). After turning on the equipment, the industrial camera collects images of the test paper, grayscales, denoises, and enhances the acquired images; according to the fitted relationship, the calculated color change area value is input into the relationship to obtain the corresponding chloride ion concentration value.
[0049] The image processing algorithm is used to analyze the color change area of the lead halide perovskite quantum dot fluorescence detection test paper in the image and calculate the color change area value of the area. The specific process is as follows: 1. Image acquisition and preprocessing: First, the industrial camera captures the fluorescence image of the test paper after it is excited by ultraviolet light and transmits it to the main controller for processing. To ensure accurate analysis, the image will undergo the following preprocessing steps: Grayscale: Convert a color image to a grayscale image to reduce color noise and highlight areas with color changes.
[0050] Denoising: Use image denoising algorithms (such as Gaussian blur, mean filtering, etc.) to remove noise from the image to ensure that the color change area is clearly visible.
[0051] Contrast enhancement: Enhance the contrast of color-changing areas by contrast stretching or histogram equalization to make them stand out more.
[0052] 2. Identification of color change areas: Threshold segmentation: According to the preset threshold, based on the gray value or color difference (for example, the characteristic wavelength of the fluorescence color change), the image threshold segmentation method is used to separate the color change area from the background. Specifically, a suitable threshold is selected to mark the pixels in the color change area of the image as foreground and the rest as background.
[0053] Region extraction: The region with color changes in the image is extracted through a segmentation algorithm (such as a contour detection algorithm) to ensure that the background area is not mistakenly identified as a changed region.
[0054] 3. Region edge detection and contour extraction: The Canny edge detection algorithm is used to extract the outline of the color change area. This can accurately determine the outer boundary of the color change area. The extracted outline will be used as the boundary of the color change area for subsequent area calculations.
[0055] 4. Area calculation: Pixel counting: According to the outline of the extracted color change area, count the number of pixels it contains. These pixels represent the area of color change.
[0056] Area estimation: Each pixel represents a certain actual area (based on the known relationship between camera resolution and image size), and the actual area value of the color change area can be obtained by multiplying the number of pixels by the unit area.
[0057] 5. Area data recording and output: The calculated relationship between the color change area value and the chloride ion concentration (obtained by standard curve fitting) is input into the system to further calculate the corresponding chloride ion concentration.
[0058] The area value can also be stored in the device for data analysis, historical data comparison and trend chart display.
[0059] 6. Result display and feedback: The calculated area value and chloride ion concentration value will be displayed on the IPS touch screen of the device, and the user can view it in real time.
[0060] Through the above image processing and algorithm steps, the system can accurately analyze the concentration of chloride ion samples and calculate the concentration of chloride ions based on the area of the color change region, providing an efficient and accurate solution for wastewater detection.
[0061] The above description is only a preferred embodiment of the present invention. It should be pointed out that a person skilled in the art can make several improvements without departing from the principle of the present invention, and these improvements should also be regarded as within the protection scope of the present invention.
Claims
1. A method for detecting chloride ions based on machine vision, characterized in that: The following steps are involved: 1) Adding a chlorine-containing solution or a chlorine-containing gas to a fluorescent test paper having lead halide perovskite quantum dots to obtain a color-changing test paper; 2) Take a picture of the test paper, obtain the fluorescence color change area data, and calculate the chloride ion concentration based on the color change area data.
2. The method for detecting chloride ions based on machine vision according to claim 1, characterized in that: The preparation method of the lead halide perovskite quantum dots is: 1) Cs2CO3, oleic acid and octadecene are heated under vacuum conditions until Cs2CO3 is completely dissolved to generate cesium oleate; then, the vacuum is changed to nitrogen and impurity gases are removed to obtain a precursor Cs-OA solution, and the Cs-OA solution is transferred to a glass sample bottle for storage while hot, cooled to a solid state at room temperature, and then heated to melt when used; 2) PbBr2, octadecene, oleic acid and oleylamine are stirred and mixed, and then heated under vacuum conditions to completely dissolve PbBr2; 3) Under nitrogen protection, use a syringe to absorb the pre-heated melted Cs-OA solution, then stir and mix it with the completely dissolved PbBr2, and then cool it; 4) adding n-hexane and acetone solution to the cooled solution, discarding the supernatant after centrifugation, and obtaining a solid after centrifugation; 5) The solid after centrifugation is dissolved in n-hexane to obtain a lead halide perovskite quantum dot solution.
3. The method for detecting chloride ions based on machine vision as claimed in claim 2, characterized in that: The preparation method of the test paper is: diluting the concentration of the lead halide perovskite quantum dot solution to 0.1-0.3 mg / mL, evenly distributing the diluted lead halide perovskite quantum dot solution on the filter paper, and drying it.
4. The method for detecting chloride ions based on machine vision as claimed in claim 2, characterized in that: In step 1), the added amounts of Cs2CO3, oleic acid and octadecene are: 1-2 g Cs2CO3, 3-6 mL oleic acid, and 10-20 mL octadecene.
5. The method for detecting chloride ions based on machine vision as claimed in claim 2, characterized in that: In step 2), the added amounts of PbBr2, octadecene, oleic acid and oleylamine are: 0.1-0.2 g PbBr2, 10-20 mL octadecene, 0.5-1.5 mL oleic acid, and 0.5-1.5 mL oleylamine.
6. The method for detecting chloride ions based on machine vision as claimed in claim 2, characterized in that: In step 2), a luminescent metal compound is also added. After the luminescent metal compound is added, step 5) finally obtains a lead halide perovskite quantum dot solution doped with a luminescent metal element.
7. The method for detecting chloride ions based on machine vision according to claim 6, characterized in that: The addition amount of the luminescent metal compound is: 0.01-0.05 g; the luminescent metal compound is: one or more of manganese bromide, europium oxide, cerium oxide, terbium bromide, and antimony oxide.
8. The method for detecting chloride ions based on machine vision according to claim 1, characterized in that: The process of calculating the chloride ion concentration based on the test paper photo is as follows: S1: Perform linear fitting on the prepared standard curve to obtain the relationship between the color change area value and the chloride ion concentration; S2: Use an industrial camera to photograph the test paper to obtain an image of the test paper; S3: grayscale, denoise and enhance the acquired image; S4: using an image processing algorithm to analyze the color change region of the test paper in the image, and calculating the color change area value of the region; S5: According to the relationship fitted in step S1, the calculated color change area value is input into the relationship to obtain the corresponding chloride ion concentration value; S6: The detected chloride ion concentration is displayed through the IPS touch screen, and the relevant concentration trend and historical data analysis are provided.
9. The method for detecting chloride ions based on machine vision according to claim 8, characterized in that: In S1, the relationship between the color change area value and the chloride ion concentration is obtained by the following steps: S11: preparing solutions of chloride ion concentrations of different concentrations, and dropping them onto a fluorescent test paper of lead halide perovskite quantum dots to obtain a test paper with color change; S12: Use ultraviolet light with a wavelength of 365nm to illuminate the test paper to stimulate the color that can be captured by the industrial camera; S13: Using an industrial camera to photograph the test paper after excitation, and obtaining an image of the color change area on the surface of the test paper; S14: Performing color analysis on the captured image, calculating the area value of the color change region, and recording the color change area values corresponding to solutions with different chloride ion concentrations; S15: Linearly fit the color change area values under different concentrations of chloride ion solutions with the corresponding chloride ion concentrations to obtain a relationship between the color change area value and the chloride ion concentration, and write the relationship into the program for subsequent detection.
10. The method for detecting chloride ions based on machine vision according to claim 8, characterized in that: In S4, the process of image processing algorithm analyzing the color change area is as follows: Use image threshold segmentation method to separate the color change area from the background; Use the Canny edge detection algorithm to extract the contours of the color change area; The calculation process of the color change area value of the color change area is: According to the outline of the extracted color change area, count the number of pixels it contains; The actual area value of the color change area is obtained by multiplying the number of pixels by the unit area.