Full-automatic liquid phase diffusion coefficient measuring device and method based on liquid core column lens

Abstract

The invention discloses a full-automatic liquid phase diffusion coefficient measuring device and method based on a liquid core column lens, and relates to the technical field of liquid phase mass transfer. The measuring device comprises a parallel light beam generating component, the liquid core column lens, an image collecting component and a processor; enabling the collimated parallel light beams to enter a liquid core column lens, controlling an image collection part to work through a processor, automatically collecting and obtaining a plurality of diffusion images in the diffusion process of the binary solution, processing each diffusion image through the processor, obtaining the position of the smallest light beam width in each diffusion image, and displaying the position of the smallest light beam width in the liquid core column lens. And calculating the liquid phase diffusion coefficient of the binary solution by combining the shooting time of each diffusion image and the first concentration, the second concentration and the calibration concentration input by the user. The liquid phase diffusion coefficient can be automatically measured, the method is suitable for non-professional personnel, the measurement time can be shortened, and the measurement precision can be improved.

Description

Technical Field

[0001] The present application relates to the field of liquid phase mass transfer technology, and in particular to a fully automatic liquid phase diffusion coefficient measurement device and method based on a liquid core cylindrical lens. Background Art

[0002] The liquid diffusion coefficient of a binary solution refers to the rate of transfer from a high concentration area to a low concentration area in the absence of external force. It is an important parameter for studying mass transfer processes and calculating mass transfer rates. It can provide important basic data for biomedicine, environmental protection, physical and chemical engineering, scientific research and teaching, etc. Therefore, the measurement method of the liquid diffusion coefficient through experiments has attracted particular attention and attention. Commonly used measurement methods include membrane pool method, Taylor dispersion method and optical interferometry method. However, these measurement methods cannot visualize the diffusion process of binary solutions, have slow measurement speeds, and have high requirements for instrument stability.

[0003] In order to solve the problems existing in the above three measurement methods, a liquid phase diffusion coefficient measurement method based on a liquid core cylindrical lens is currently proposed. This measurement method can capture multiple diffusion images during the diffusion process, that is, the diffusion process of the binary solution can be visualized. However, this measurement method requires manual control of the diffusion image capture process, manual processing of the diffusion image, extraction of the same width position of multiple diffusion images, and manual calculation of the liquid phase diffusion coefficient based on the same width position of the multiple diffusion images and Fick's second law, resulting in the need for the participation of professionals to perform the measurement. For non-professionals, the measurement is difficult, and the manual extraction of the same width position and the calculation of the liquid phase diffusion coefficient will result in long measurement time, poor measurement accuracy, and a large impact of human factors. There is also the problem that the same diffusion image may have multiple locations with the same width. At this time, extracting the same width position of multiple diffusion images will affect subsequent calculations, further resulting in poor measurement accuracy. Summary of the invention

[0004] The purpose of this application is to provide a fully automatic liquid phase diffusion coefficient measurement device and method based on a liquid core cylindrical lens, which can automatically complete the measurement of the liquid phase diffusion coefficient, is suitable for non-professionals, and can shorten the measurement time, improve the measurement accuracy, and provide convenience for the application and promotion of the instrument.

[0005] To achieve the above objectives, this application provides the following solutions:

[0006] In a first aspect, the present application provides a fully automatic liquid phase diffusion coefficient measuring device based on a liquid core column lens, the fully automatic liquid phase diffusion coefficient measuring device based on a liquid core column lens comprising:

[0007] A parallel light beam generating component is used to generate a collimated parallel light beam and to make the collimated parallel light beam incident on a liquid core cylindrical lens;

[0008] The liquid core cylindrical lens is filled with a binary solution; the binary solution includes a first solution and a second solution, the first solution is located above the second solution, and a first concentration of the first solution is less than a second concentration of the second solution;

[0009] An image acquisition component is used to take multiple shots of the liquid core cylindrical lens incident by the collimated parallel light beam to obtain multiple diffusion images of the binary solution during diffusion; the beam width at any lateral position in the diffusion image corresponds to the solution concentration at the height corresponding to the lateral position in the liquid core cylindrical lens;

[0010] A processor is respectively connected to the parallel light beam generating component and the image acquisition component for controlling the parallel light beam generating component to start working, controlling the image acquisition component to work based on an initial time, a time step and a number of shots input by a user, processing each diffusion image respectively to obtain the position of the thinnest light beam width in each diffusion image, and calculating the liquid phase diffusion coefficient of the binary solution based on the position of the thinnest light beam width in each diffusion image, the shooting time of each diffusion image and a first concentration, a second concentration and a calibration concentration input by a user; wherein the initial time is the time to start shooting the diffusion image, the time step is the time interval between two adjacent shootings of the diffusion image, and the calibration concentration corresponds to the thinnest light beam width.

[0011] In a second aspect, the present application provides a fully automatic liquid phase diffusion coefficient measurement method based on a liquid core column lens, which is applied to the above-mentioned fully automatic liquid phase diffusion coefficient measurement device based on a liquid core column lens, and the fully automatic liquid phase diffusion coefficient measurement method based on a liquid core column lens includes:

[0012] Issuing a first control instruction; the first control instruction is used to control the parallel light beam generating component to start working, generate a collimated parallel light beam, and inject the collimated parallel light beam into the liquid core cylindrical lens;

[0013] A second control instruction is issued based on the initial time, time step and number of shots input by the user; the second control instruction is used to control the image acquisition component to take multiple shots of the liquid core cylindrical lens incident by the collimated parallel light beam to obtain multiple diffusion images of the binary solution during diffusion; the initial time is the time to start taking the diffusion image, and the time step is the time interval between two adjacent shots of the diffusion image;

[0014] Process each diffuse image separately to obtain the position of the thinnest beam width in each diffuse image;

[0015] The liquid phase diffusion coefficient of the binary solution is calculated based on the position of the thinnest beam width in each diffusion image, the shooting time of each diffusion image, and the first concentration, the second concentration, and the calibration concentration input by the user.

[0016] According to the specific embodiments provided in this application, this application has the following technical effects:

[0017] The present application provides a fully automatic liquid phase diffusion coefficient measurement device and method based on a liquid core column lens, comprising a parallel light beam generating component, a liquid core column lens, an image acquisition component and a processor. The parallel light beam generating component is controlled by the processor to start working, and a collimated parallel light beam is incident on the liquid core column lens. The image acquisition component is controlled by the processor to work, and the liquid core column lens incident with the collimated parallel light beam is photographed multiple times to obtain multiple diffusion images of the binary solution diffusion process. Each diffusion image is processed by the processor respectively to obtain the position of the thinnest light beam width in each diffusion image, and the liquid phase diffusion coefficient of the binary solution is calculated based on the position of the thinnest light beam width in each diffusion image, the shooting time of each diffusion image, and the first concentration, the second concentration and the calibration concentration input by the user. This application only requires the user to input parameters such as initial time, time step, number of shots, first concentration, second concentration and calibration concentration, and the processor can automatically complete the acquisition and processing of the diffusion image and the calculation of the liquid phase diffusion coefficient, thereby automatically completing the measurement of the liquid phase diffusion coefficient. The entire measurement process does not require the participation of professionals and is suitable for non-professionals. Compared with the manual extraction of the same width position and the calculation of the liquid phase diffusion coefficient, it can shorten the measurement time and improve the measurement accuracy. In addition, for extracting the position of the thinnest beam width, only one position of the thinnest beam width will be extracted from a diffusion image. Compared with the method of extracting the same width position of multiple diffusion images, which may affect subsequent calculations due to the appearance of multiple locations of the same width position, it can further improve the measurement accuracy and solve the problem that the liquid phase diffusion coefficient cannot be measured quickly and accurately, and the measurement is difficult for non-professionals. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0019] Figure 1 A schematic structural diagram of a fully automatic liquid phase diffusion coefficient measurement device based on a liquid core cylindrical lens provided in Example 1 of the present application.

[0020] Figure 2 This is a schematic diagram of the structure of the liquid core cylindrical lens provided in Example 1 of the present application; wherein, Figure 2 (a) is a real picture of the liquid core cylindrical lens. Figure 2 (b) in the figure is a diagram of the liquid core cylindrical lens model.

[0021] Figure 3 The collimated parallel light beam provided in Example 1 of the present application passes through the liquid core cylindrical lens with refractive indexes of n and 1 、n 2 、n 3 、n 4 、n 5 Schematic diagram of the image formed after a single homogeneous solution is formed.

[0022] Figure 4 This is a flow chart for calculating the liquid phase diffusion coefficient provided in Example 1 of the present application.

[0023] Figure 5 Schematic diagram of the human-computer interaction interface of the liquid phase diffusion coefficient measurement software provided in Example 1 of the present application.

[0024] Figure 6 This is a schematic diagram of extracting the position of the thinnest beam width in the diffusion image of the potassium chloride solution provided in Example 1 of the present application.

[0025] Figure 7 Schematic diagram of extracting the position of the thinnest beam width in the diffusion image of the ethylene glycol solution provided in Example 1 of the present application.

[0026] Figure 8 This is a schematic diagram of the liquid phase diffusion coefficient measurement results of 0.33 mol / L potassium chloride solution and 3 mol / L potassium chloride solution provided in Example 1 of the present application.

[0027] Fig. 9 This is a schematic diagram of the measurement results of the liquid phase diffusion coefficient of pure water and 100% pure ethylene glycol solution provided in Example 1 of the present application.

[0028] Fig.10 A schematic flow chart of a fully automatic liquid phase diffusion coefficient measurement method based on a liquid core cylindrical lens provided in Example 2 of the present application.

[0029] Fig.11 A schematic diagram of the structure of a computer device provided in Example 3 of the present application.

[0030] Reference numerals:

[0031] 1-Laser; 2-Attenuation plate; 3-Spatial filter; 4-Converging lens; 5-Width-limiting slit; 6-Liquid core cylindrical lens; 7-Image acquisition component. DETAILED DESCRIPTION

[0032] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0033] Example 1

[0034] This embodiment is used to provide a fully automatic liquid phase diffusion coefficient measurement device based on a liquid core cylindrical lens, such as Figure 1 As shown, the fully automatic liquid phase diffusion coefficient measuring device based on the liquid core cylindrical lens includes:

[0035] The parallel light beam generating component is used to generate a collimated parallel light beam and to make the collimated parallel light beam incident on the liquid core cylindrical lens 6 .

[0036] The liquid core cylindrical lens 6 is filled with a binary solution, the binary solution includes a first solution and a second solution, the first solution is located above the second solution, and the first concentration of the first solution is less than the second concentration of the second solution. When injecting, the second solution is first injected into the liquid core cylindrical lens 6, and then the first solution is injected into the liquid core cylindrical lens 6.

[0037] The image acquisition component 7 is used to take multiple shots of the liquid core column lens 6 incident with the collimated parallel light beam to obtain multiple diffusion images of the binary solution during diffusion. The beam width at any lateral position in the diffusion image corresponds to the solution concentration at the height corresponding to the lateral position in the liquid core column lens 6.

[0038] The processor is respectively connected to the parallel beam generating component and the image acquisition component 7 for controlling the parallel beam generating component to start working, and controls the image acquisition component 7 to work based on the initial time, time step and number of shots input by the user, and processes each diffusion image to obtain the position of the thinnest beam width in each diffusion image, and calculates the liquid phase diffusion coefficient of the binary solution based on the position of the thinnest beam width in each diffusion image, the shooting time of each diffusion image, and the first concentration, second concentration and calibration concentration input by the user. Among them, the initial time is the time to start shooting the diffusion image, the time step is the time interval between two adjacent diffusion images, the number of shots can be 10-20 diffusion images, and the calibration concentration corresponds to the thinnest beam width.

[0039] The parallel beam generating component of the present embodiment is used to first emit a monochromatic beam, which is a high-intensity, monochromatic, coherent beam, such as a laser, and then the monochromatic beam is processed accordingly to generate a collimated parallel beam. At this time, the parallel beam generating component may include: a laser 1 and an attenuation plate 2, a spatial filter 3, a converging lens 4 and a width-limiting slit 5 arranged in sequence along the laser propagation direction. The laser 1 may be a semiconductor laser, which is used to emit laser light and provide a light source. The attenuation plate 2 is used to attenuate the light intensity by utilizing the absorption characteristics of the material to light. The spatial filter 3 and the converging lens 4 constitute a collimated beam expansion component. The spatial filter 3 is used to filter out high-frequency information such as scattered light and stray light caused during transmission, and make the light beam output as a point light source. Ideal spherical wave, the converging lens 4 converts the point light source into parallel light, that is, when the input point light source is at the focus of the lens, parallel light is output, the width-limiting slit 5 is used to limit the beam width, the laser 1 emits a laser, the laser passes through the attenuation plate 2 and is attenuated, the attenuated laser enters the spatial filter 3 to eliminate part of the stray light, that is, the stray light is filtered out to form a point light source, and then the point light source is collimated and expanded into a beam of parallel light through the converging lens 4 to generate a collimated parallel light beam, the collimated parallel light beam passes through the width-limiting slit 5 and is incident on the liquid core column lens 6, specifically on the center position of the liquid core column lens 6, and after being refracted by the liquid core column lens 6, it is imaged on the image acquisition component 7, which is equivalent to the image acquisition component 7 performing imaging and saving in real time to obtain a diffuse image.

[0040] The liquid core cylindrical lens 6 uses the refractive index of the liquid to change the propagation path of the light, thereby measuring the refractive index and diffusion coefficient of the liquid. Figure 2 As shown, the liquid core cylindrical lens 6 is composed of two negative meniscus cylindrical lenses (also called negative meniscus lenses) glued together. It not only serves as a core imaging element, but also as a diffusion pool for the binary solution. During measurement, the liquid core cylindrical lens 6 is filled with a binary solution, the binary solution includes a first solution and a second solution, the first solution is located above the second solution, and the first concentration of the first solution is less than the second concentration of the second solution, and the collimated parallel light beam is incident on the curved surface of the liquid core cylindrical lens 6.

[0041] In this embodiment, the image acquisition component 7 can be a CMOS (Complementary Metal-Oxide-Semiconductor) camera, and the laser 1, attenuation plate 2, collimating beam expansion component, width-limiting slit 5, liquid core cylindrical lens 6, image acquisition component 7, and processor are placed in sequence.

[0042] When solutions of different concentrations are injected into the liquid core cylindrical lens 6, different concentrations correspond to different refractive indices. At this time, when the collimated parallel light beam passes through the liquid core cylindrical lens 6 for imaging, images with different beam widths will be imaged on the image acquisition component 7, such as Figure 3As shown, solutions of different concentrations are injected into the liquid core cylindrical lens 6, which is equivalent to injecting solutions of different refractive indices. Specifically, solutions with refractive indices n and n are injected respectively. 1 、n 2 、n 3 、n 4 、n 5 The solution obtained images with different beam widths and different refractive indices n 1 、n 2 、n 3 、n 4 、n 5 Corresponding to different beam widths, Figure 3 The longitudinal direction is the height direction of the liquid core cylindrical lens 6, and the white line is the light beam. Figure 3 The lateral width is the beam width. Obviously, different concentrations correspond to different refractive indices, and different refractive indices correspond to different beam widths.

[0043] When a binary solution is injected into the liquid core column lens 6, as the binary solution continues to diffuse, different diffusion images will be formed after imaging. Since a concentration gradient will be formed during the diffusion of the binary solution, the refractive indexes corresponding to the binary solutions at different heights will also be different. Therefore, there will be different beam widths in the diffusion image. The beam width at any lateral position in the diffusion image corresponds to the solution concentration at the height corresponding to the lateral position in the liquid core column lens 6, and the beam width is the longitudinal width of the beam in the diffusion image.

[0044] In this embodiment, the processor may be a host computer. In order to realize fully automatic measurement, liquid phase diffusion coefficient measurement software is installed in the processor. The diffusion image is collected by the image acquisition component 7, and the liquid phase diffusion coefficient measurement software is used to analyze and calculate to obtain the liquid phase diffusion coefficient. The liquid phase diffusion coefficient measurement software includes a beam generating module, an image acquisition module, an image processing module and a liquid phase diffusion coefficient calculation module. The beam generating module is used to control the parallel beam generating component to start working, generate a collimated parallel beam, and incident the collimated parallel beam to the liquid core column lens 6. The image acquisition module collects the diffusion image in real time. The specific parameter settings include: setting the name of the image acquisition component 7, the time step between the diffusion images and the storage location of the diffusion image. It is specifically used to control the image acquisition component 7 based on the initial time, time step and number of shots input by the user, and to take multiple shots of the liquid core column lens 6 incident with the collimated parallel beam to obtain multiple diffusion images during the diffusion process of the binary solution. The image processing module is used to process each diffusion image separately to obtain the position of the thinnest beam width in each diffusion image, so as to extract features of the diffusion image and automatically export it as a CSV file. The liquid phase diffusion coefficient calculation module automatically calculates the liquid phase diffusion coefficient. The specific parameter settings include: setting the concentration of the binary solution to be measured (the first concentration and the second concentration), the calibration solution concentration (calibration concentration), the initial time and the time step. It is specifically used to calculate the liquid phase diffusion coefficient of the binary solution based on the position of the thinnest beam width in each diffusion image, the shooting time of each diffusion image, and the first concentration, second concentration and calibration concentration input by the user.

[0045] In order to be able to measure the liquid phase diffusion coefficient, in this embodiment, a solution of calibrated concentration is injected into the liquid core column lens 6 in advance. When the image acquisition component 7 moves to the focal plane position of the liquid core column lens 6, the acquisition plane of the image acquisition component 7 receives an image with sharp and thin straight lines of the same width, that is, the collimated parallel light beams converge into a thin straight line after passing through the liquid core column lens 6. The distance between the liquid core column lens 6 and the image acquisition component 7 is continuously adjusted until the light beam width in the image obtained by imaging is the thinnest. Therefore, in this embodiment, the distance between the liquid core column lens 6 and the image acquisition component 7 is determined according to a preset principle. The preset principle is that the calibration concentration corresponds to the thinnest light beam width. When diffusion is performed later, it can be clearly determined that the concentration corresponding to the thinnest light beam width in the diffusion image is the calibration concentration.

[0046] In order to improve the measurement accuracy, the difference between the calibration concentration and the first concentration is smaller than a preset value. The preset value can be determined according to user needs. The goal is to make the calibration concentration and the first concentration as close as possible, thereby improving the measurement accuracy.

[0047] like Figure 4 As shown, the processor is connected to the image acquisition component 7. Based on the initial time, time step and number of shots input by the user, the time interval and storage position for saving each diffusion image are set in the image acquisition module, and the diffusion images at multiple moments are acquired in real time. Considering the factors such as convection after the binary solution is injected, the binary solution is unstable and needs to wait for a certain time before the binary solution can be stable. Therefore, the initial time needs to be set. According to experience, the initial time can be selected as 1200s. Of course, the initial time can also be selected according to user needs.

[0048] After the image acquisition module completes the real-time acquisition of the diffusion image, all the acquired diffusion images enter the image processing module, which extracts the features of the position of the thinnest beam width of the diffusion image and saves the position of the thinnest beam width as a CSV file in real time. At this time, each diffusion image is processed separately to obtain the position of the thinnest beam width in each diffusion image, specifically including: for each diffusion image, the diffusion image is denoised, brightness adjusted and binarized to obtain a binarized image, in which the pixel points corresponding to the beam in the binarized image are the first color, and the pixel points corresponding to the background other than the beam are the second color; traverse each column of pixels in the binarized image, extract the number of pixels of the first color in each column of pixels, and obtain the beam width corresponding to each column of pixels; select the minimum value of all beam widths as the thinnest beam width, and record the number of pixel columns corresponding to the thinnest beam width to obtain the position of the thinnest beam width in the diffusion image, so as to extract the features of the diffusion image and read the thin layer position of each diffusion image, which is the position of the thinnest beam width.

[0049] Start the liquid-phase diffusion coefficient calculation module. The user enters the initial parameters such as the first concentration, the second concentration, the calibration concentration, the initial time and the time step in the human-computer interaction interface, clicks to run the calculation, and the liquid-phase diffusion coefficient calculation module automatically calculates and quickly gives the liquid-phase diffusion coefficient of the configured binary solution. At this time, based on the position of the thinnest beam width in each diffusion image, the shooting time of each diffusion image, and the first concentration, second concentration and calibration concentration entered by the user, the liquid-phase diffusion coefficient of the binary solution is calculated, specifically including: taking the square root of the shooting time as the independent variable, taking the position of the thinnest beam width as the dependent variable, and performing linear fitting based on the position of the thinnest beam width in each diffusion image and the shooting time of each shot image to obtain a linear fitting equation. In the process of linear fitting, the thin layer position Z and The liquid phase diffusion coefficient of the binary solution is calculated based on the slope of the linear fitting equation and the first concentration, second concentration and calibration concentration input by the user.

[0050] According to the diffusion equation of binary solution, combined with the initial conditions and boundary conditions, a concentration distribution function can be obtained. The diffusion equation is:

[0051]

[0052] Wherein, C(Z, t) is the calibration concentration corresponding to the thinnest beam width, Z is the position of the thinnest beam width, t is the time; and D is the liquid phase diffusion coefficient of the binary solution.

[0053] The initial conditions are:

[0054]

[0055] Where x is the lateral position of the diffusion image; C 1 is the first concentration; C 2 is the second concentration.

[0056] The boundary conditions are:

[0057]

[0058] Combining the initial and boundary conditions, the solution to the diffusion equation can be expressed in the form of a Gaussian error function:

[0059]

[0060] Among them, erf is the error function.

[0061] The above formula is the positional relationship between concentration and time after a binary solution has diffused for a certain period of time. Let erfinv be the inverse error function, then the above formula can be rewritten as:

[0062]

[0063] Among them, erfinv is the inverse error function.

[0064] By squaring and shifting the terms in the above formula, we can further deduce:

[0065]

[0066] By selecting the calibration concentration, the first concentration, and the second concentration, and fitting Z and The liquid phase diffusion coefficient can be calculated based on the above formula.

[0067] The calculation formula of liquid phase diffusion coefficient is:

[0068]

[0069] Where D is the liquid diffusion coefficient; k is the slope of the linear fitting equation; erfinv is the inverse error function; C(Z, t) is the calibration concentration, Z is the position of the thinnest beam width, and t is time; C 1 is the first concentration; C 2 is the second concentration.

[0070] In this embodiment, the processor has a human-computer interaction interface, such as Figure 5 As shown, the human-computer interaction interface includes an input box, an operation box, and a result display box. The input box is used for the user to input initial parameters. The initial parameters include the first concentration (i.e. Figure 5 The upper liquid concentration in), the second concentration (i.e. Figure 5 concentration in the lower solution), calibration concentration, initial time and time step, run frame (i.e. Figure 5 The Run Calculation in the Result Display Box is used to start the processor after the user clicks it, and the Result Display Box is used to show the user the liquid phase diffusion coefficient of the binary solution (i.e. Figure 5 The original data and the fitting line can also be displayed. The original data are the position of the thinnest beam width of each diffusion image and the shooting time of each diffusion image. The fitting line is the fitting line obtained by fitting the original data with the square root of the shooting time as the horizontal coordinate and the position of the thinnest beam width as the vertical coordinate. The original image example with the thin layer position marked can also be displayed. The original image example with the thin layer position marked is a diffusion image in which the position of the thinnest beam width is marked. The calculated error function A value can also be displayed. The error function A value is The linear fit equation can also be displayed.

[0071] The collimated parallel light beam is imaged on the image acquisition component 7 through the liquid core column lens 6 to obtain a diffusion image of the binary solution. The diffusion image is collected in real time by the liquid phase diffusion coefficient measurement software, and the diffusion image is automatically processed to obtain the fitting curve and linear fitting equation of the position and time of the thinnest light beam width, and the liquid phase diffusion coefficient is further calculated. The user enters the configured binary solution concentration, the calibration concentration of the calibration solution, the initial time, and the time step in the human-computer interaction interface, and the liquid phase diffusion coefficient can be calculated with one click to quickly obtain the required liquid phase diffusion coefficient. The diffusion image of the binary solution is obtained in real time through the liquid core column lens 6 and the liquid phase diffusion coefficient measurement software, and the liquid phase diffusion coefficient is automatically measured by extracting the features of the diffusion image. The fully automatic liquid phase diffusion coefficient measurement device has the characteristics of simple operation, accurate measurement, and short measurement time.

[0072] At present, there is no device specifically used to measure the liquid phase diffusion coefficient, so it is very necessary to invent a fully automatic liquid phase diffusion coefficient measuring device. This embodiment discloses a fully automatic liquid phase diffusion coefficient measuring device based on a liquid core column lens, which relates to the field of liquid phase diffusion coefficient measurement of binary solutions. The measuring device includes: a laser 1, an attenuation plate 2, a spatial filter 3, a converging lens 4, a width-limiting slit 5, a liquid core column lens 6, an image acquisition component 7, a processor, and liquid phase diffusion coefficient measurement software. The laser 1 emits a laser, which passes through the attenuation plate 2, the spatial filter 3, the converging lens 4, and the width-limiting slit 5 to form a collimated parallel light beam. The collimated parallel light beam passes through the liquid core column lens 6 to form an image on the image acquisition component 7 to obtain a diffusion image of the binary solution. The fully automatic liquid phase diffusion coefficient measuring device and the combined The liquid phase diffusion coefficient measurement software for automatically measuring the liquid phase diffusion coefficient is developed by combining the feature processing of the diffusion image. By using the liquid phase diffusion coefficient measurement software, the diffusion image can be collected in real time, and the features of the collected diffusion image can be extracted, and the liquid phase diffusion coefficient can be further automatically calculated. The use of the liquid phase diffusion coefficient measurement software can reduce the reading error caused by human factors, greatly shorten the measurement time, and develop a human-computer interaction interface. By using the fully automatic liquid phase diffusion coefficient measurement device, not only can the liquid phase diffusion coefficient of the binary solution be measured accurately and quickly, but also non-professionals can quickly and accurately measure the liquid phase diffusion coefficient.

[0073] This embodiment mainly adopts Figure 1 The fully automatic liquid phase diffusion coefficient measuring device shown obtains diffusion images at different times, and automatically calculates the liquid phase diffusion coefficient through the liquid phase diffusion coefficient measurement software by the position change of the thinnest light beam width in the diffusion image with time. In the following, this embodiment uses the fully automatic liquid phase diffusion coefficient measuring device to measure potassium chloride aqueous solution and ethylene glycol aqueous solution as an example to calculate their diffusion coefficients.

[0074] like Figure 4 As shown, the specific steps include:

[0075] (1) Build a fully automatic liquid phase diffusion coefficient measurement device.

[0076] The fully automatic liquid phase diffusion coefficient measurement device used in this example is Figure 1As shown, it is divided into five parts: 1) a light source component consisting of a low-power semiconductor laser with a laser wavelength λ=589nm and a maximum power of 20mw and an attenuation plate 2, which emits a monochromatic laser beam; 2) a collimating and expanding component consisting of a 40x microscope objective, a spatial filter 3 with an aperture of 15μm pinhole and a converging lens 4 with a focal length of 500mm, which collimates and expands the monochromatic laser beam to obtain a collimated parallel beam; 3) a width-limiting slit 5 with adjustable width, which serves as a width-limiting element for the collimated parallel beam; 4) a liquid core column lens 6 as an imaging element and a liquid phase diffusion cell; 5) an image acquisition component 7 based on a CMOS camera, with a resolution of 4090×3072pixel and a pixel size of 5.5×5.5 microns.

[0077] (2) Prepare the required solution

[0078] At room temperature (25°C), pure ethylene glycol solution, 99.9% potassium chloride solid particles and pure water are used to prepare the test solution. In this example, the test solutions are: a group of binary solutions of 0.33mol / L potassium chloride solution and 3mol / L potassium chloride solution, and a group of binary solutions of pure water and 100% pure ethylene glycol solution. The concentrations corresponding to the test solutions are the upper liquid concentration and the lower liquid concentration required to be input in the human-computer interaction interface. For example, for the diffusion system of the binary solution of 0.33mol / L potassium chloride solution and 3mol / L potassium chloride solution, the upper liquid concentration is the concentration of 0.33mol / L potassium chloride solution, and the lower liquid concentration is the concentration of 3mol / L potassium chloride solution. For the diffusion system of the binary solution of pure water and 100% pure ethylene glycol solution, the upper liquid concentration is the concentration of pure water, and the lower liquid concentration is the concentration of 100% pure ethylene glycol solution.

[0079] Before injecting the binary solution into the liquid core column lens 6, calibration is required. At room temperature (25°C), the calibration solution is added to the liquid core column lens 6, and the position of the CMOS camera is adjusted so that the image of the calibration solution contains a bright, sharp bright line, that is, the beam width is the thinnest at this time. For the diffusion system of a binary solution of 0.33mol / L potassium chloride solution and 3mol / L potassium chloride solution, 0.487mol / L potassium chloride solution is used for calibration, and for the diffusion system of a binary solution of pure water and 100% pure ethylene glycol solution, 5% ethylene glycol solution is used for calibration.

[0080] The refractive index n of the solution to be tested was measured using an Abbe refractometer with an accuracy of 0.0002. The relationship between the prepared solution and the refractive index is shown in Table 1.

[0081] Table 1 Relationship between the prepared solution and the refractive index

[0082] Potassium chloride solution concentration Refractive index (n) Ethylene glycol solution concentration Refractive index (n) 0.33 mol / L potassium chloride 1.3364 Pure aqueous solution 1.3333 3mol / L potassium chloride 1.3600 100% pure ethylene glycol solution 1.4296 0.487mol / L potassium chloride 1.3376 5% ethylene glycol solution 1.3389

[0083] As the binary diffusion process proceeds, the liquid phase diffusion coefficient of the binary solution can be calculated by extracting the characteristics of the thinnest beam width at the refractive index position of the calibration solution and obtaining the functional relationship between the position of the thinnest beam width and time.

[0084] (3) A fully automatic liquid phase diffusion coefficient measurement device is constructed, which includes a semiconductor laser, an attenuation plate 2, a spatial filter 3, a converging lens 4, a width-limiting slit 5, a liquid core column lens 6, an image acquisition component 7 and a processor. After the required solution is configured, the liquid phase diffusion coefficient measurement software is started, and the initial time, time step, number of shots, diffusion image storage location, etc. are input to perform real-time acquisition of the diffusion image.

[0085] (4) Based on the image characteristics of the liquid phase diffusion coefficient measured by the imaging method, the collected diffusion image is processed by denoising, brightness processing and binarization processing through the image processing module of the liquid phase diffusion coefficient measurement software.

[0086] (5) Feature extraction is performed on the processed diffusion image. Since 0.487 mol / L potassium chloride solution is used for calibration, the features extracted in this example include: the position where the refractive index of 0.487 mol / L potassium chloride solution is 1.3376, that is, the position where the thinnest beam width of the diffusion image is extracted, such as Figure 6 As shown in FIG. 1 , the intersection of the red line and the white line in the diffuse image is the feature position (i.e., the position of the thinnest beam width). Since 5% ethylene glycol solution is used for calibration, the features extracted in this example include: the position where the refractive index of 5% ethylene glycol solution is 1.3389, that is, the position of the thinnest beam width of the diffuse image is extracted, such as Figure 7 As shown, the intersection of the red line and the white line in the diffusion image is the feature position. Figure 6 and Figure 7 These are only example images of this embodiment. During the measurement process, multiple diffusion images need to be processed.

[0087] (6) After the image processing module completes the image processing process, the liquid phase diffusion coefficient calculation module performs automatic calculation. By inputting the upper liquid concentration, lower liquid concentration, calibration concentration, initial time, and time step in the human-computer interaction interface of the liquid phase diffusion coefficient measurement software, and clicking Run Calculation, the relationship between the thin layer position and time can be obtained, and the measurement result of the liquid phase diffusion coefficient can be obtained, such as Figure 8 and Fig. 9 shown.

[0088] The liquid phase diffusion coefficients of two groups of binary solutions, namely, 0.33 mol / L potassium chloride solution and 3 mol / L potassium chloride solution and pure water and 100% pure ethylene glycol solution, were calculated by using liquid phase diffusion coefficient measurement software and are shown in Table 2.

[0089] Table 2 Measurement results of potassium chloride and ethylene glycol solution

[0090]

[0091] In Table 2, the literature value refers to the liquid phase diffusion coefficient given in existing literature.

[0092] By measuring the liquid phase diffusion coefficients of 0.33 mol / L potassium chloride solution and 3 mol / L potassium chloride solution, as well as the liquid phase diffusion coefficients of pure water and 100% pure ethylene glycol solution, their relative errors are within 5%, proving the accuracy of the measuring device.

[0093] The present embodiment provides an instrument for automatically measuring the liquid phase diffusion coefficient based on a liquid core column lens 6, and adopts a lens imaging method to obtain a diffusion image of a binary solution. After a collimated parallel light beam passes through the liquid core column lens 6, a diffusion image is formed on its focal plane. By automatically collecting the diffusion image, automatically extracting the thin layer position, and automatically measuring the liquid phase diffusion coefficient, the measurement operation becomes simpler, the calculation result becomes more accurate, and non-professionals can also measure the liquid phase diffusion coefficient, which greatly shortens the time required for measuring the liquid phase diffusion coefficient and significantly improves work efficiency.

[0094] Example 2

[0095] This embodiment provides a fully automatic liquid phase diffusion coefficient measurement method based on a liquid core column lens, which is applied to the fully automatic liquid phase diffusion coefficient measurement device based on a liquid core column lens described in Example 1. Fig.10 As shown, the fully automatic liquid phase diffusion coefficient measurement method based on the liquid core cylindrical lens includes:

[0096] S1: issuing a first control instruction; the first control instruction is used to control the parallel light beam generating component to start working, generate a collimated parallel light beam, and make the collimated parallel light beam incident on the liquid core cylindrical lens.

[0097] S2: issuing a second control instruction based on the initial time, time step and number of shots input by the user; the second control instruction is used to control the operation of the image acquisition component, and to take multiple shots of the liquid core cylindrical lens incident by the collimated parallel light beam to obtain multiple diffusion images during the diffusion process of the binary solution; the initial time is the time to start taking the diffusion image, and the time step is the time interval between two adjacent shots of the diffusion image.

[0098] S3: Process each diffusion image separately to obtain the position of the thinnest beam width in each diffusion image.

[0099] S4: Calculate the liquid phase diffusion coefficient of the binary solution based on the position of the thinnest beam width in each diffusion image, the shooting time of each diffusion image, and the first concentration, the second concentration, and the calibration concentration input by the user.

[0100] Among them, each diffuse image is processed respectively to obtain the position of the thinnest beam width in each diffuse image, specifically including: for each diffuse image, denoising, brightness adjustment and binarization are performed on the diffuse image to obtain a binary image, in which the pixel points corresponding to the light beam in the binary image are the first color, and the pixel points corresponding to the background other than the light beam are the second color; traversing each column of pixel points in the binary image, extracting the number of pixel points of the first color in each column of pixel points, and obtaining the beam width corresponding to each column of pixel points; selecting the minimum value of all beam widths as the thinnest beam width, and recording the number of pixel columns corresponding to the thinnest beam width, to obtain the position of the thinnest beam width in the diffuse image.

[0101] Among them, based on the position of the thinnest beam width in each diffusion image, the shooting time of each diffusion image, and the first concentration, second concentration and calibration concentration input by the user, the liquid phase diffusion coefficient of the binary solution is calculated, specifically including: taking the square root of the shooting time as the independent variable, taking the position of the thinnest beam width as the dependent variable, performing linear fitting based on the position of the thinnest beam width in each diffusion image and the shooting time of each diffusion image, to obtain a linear fitting equation; using the slope of the linear fitting equation and the first concentration, second concentration and calibration concentration input by the user to calculate the liquid phase diffusion coefficient of the binary solution.

[0102] The calculation formula of liquid phase diffusion coefficient is:

[0103]

[0104] Where D is the liquid diffusion coefficient; k is the slope of the linear fitting equation; erfinv is the inverse error function; C(Z, t) is the calibration concentration, Z is the position of the thinnest beam width, and t is time; C 1 is the first concentration; C 2 is the second concentration.

[0105] Among them, the initial time is 1200s.

[0106] Example 3

[0107] In an exemplary embodiment, a computer device is provided. The computer device may be a server or a terminal. The internal structure diagram thereof may be as follows: Fig.11As shown. The computer device includes a processor, a memory, an input / output interface (Input / Output, referred to as I / O) and a communication interface. The processor, the memory and the input / output interface are connected through a system bus, and the communication interface is connected to the system bus through the input / output interface. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system, a computer program and a database. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The database of the computer device is used to store data. The input / output interface of the computer device is used to exchange information between the processor and an external device. The communication interface of the computer device is used to communicate with an external terminal through a network connection. When the computer program is executed by the processor, a fully automatic liquid phase diffusion coefficient measurement method based on a liquid core column lens is implemented.

[0108] Those skilled in the art will understand that Fig.11 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0109] In an exemplary embodiment, a computer device is provided, including a memory and a processor, wherein a computer program is stored in the memory, and when the processor executes the computer program, the fully automatic liquid phase diffusion coefficient measurement method based on the liquid core cylindrical lens in Example 2 is implemented.

[0110] Example 4

[0111] In an exemplary embodiment, a computer-readable storage medium is provided, storing a computer program, which, when executed by a processor, implements the fully automatic liquid phase diffusion coefficient measurement method based on a liquid core cylindrical lens in Example 2.

[0112] Example 5

[0113] In an exemplary embodiment, a computer program product is provided, including a computer program, which, when executed by a processor, implements the fully automatic liquid phase diffusion coefficient measurement method based on a liquid core cylindrical lens in Example 2.

[0114] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, stored data, displayed data, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of relevant data must comply with relevant regulations.

[0115] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0116] This article uses specific examples to illustrate the principles and implementation methods of this application. The description of the above embodiments is only used to help understand the method and core ideas of this application. At the same time, for those skilled in the art, according to the ideas of this application, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting this application.

Claims

1. A fully automatic liquid phase diffusion coefficient measurement device based on a liquid core cylindrical lens, characterized in that: The fully automatic liquid phase diffusion coefficient measuring device based on the liquid core cylindrical lens comprises: A parallel light beam generating component is used to generate a collimated parallel light beam and to make the collimated parallel light beam incident on a liquid core cylindrical lens; The liquid core cylindrical lens is filled with a binary solution; the binary solution includes a first solution and a second solution, the first solution is located above the second solution, and a first concentration of the first solution is less than a second concentration of the second solution; An image acquisition component is used to take multiple shots of the liquid core cylindrical lens incident by the collimated parallel light beam to obtain multiple diffusion images of the binary solution during diffusion; the beam width at any lateral position in the diffusion image corresponds to the solution concentration at the height corresponding to the lateral position in the liquid core cylindrical lens; A processor is respectively connected to the parallel light beam generating component and the image acquisition component for controlling the parallel light beam generating component to start working, controlling the image acquisition component to work based on an initial time, a time step and a number of shots input by a user, processing each diffusion image respectively to obtain the position of the thinnest light beam width in each diffusion image, and calculating the liquid phase diffusion coefficient of the binary solution based on the position of the thinnest light beam width in each diffusion image, the shooting time of each diffusion image and a first concentration, a second concentration and a calibration concentration input by a user; wherein the initial time is the time to start shooting the diffusion image, the time step is the time interval between two adjacent shootings of the diffusion image, and the calibration concentration corresponds to the thinnest light beam width.

2. The fully automatic liquid phase diffusion coefficient measuring device based on liquid core cylindrical lens according to claim 1 is characterized in that: The parallel light beam generating component comprises: a laser, and an attenuation plate, a spatial filter, a converging lens and a width-limiting slit which are sequentially arranged along the laser propagation direction.

3. The fully automatic liquid phase diffusion coefficient measuring device based on liquid core cylindrical lens according to claim 1 is characterized in that: The distance between the liquid core cylindrical lens and the image acquisition component is determined according to a preset principle, and the preset principle is that the calibration concentration corresponds to the thinnest light beam width.

4. The fully automatic liquid phase diffusion coefficient measuring device based on liquid core cylindrical lens according to claim 1 is characterized in that: The difference between the calibration concentration and the first concentration is less than a preset value.

5. The fully automatic liquid phase diffusion coefficient measuring device based on liquid core cylindrical lens according to claim 1 is characterized in that: The processor has a human-computer interaction interface, which includes an input box, an operation box and a result display box. The input box is used for the user to input initial parameters, the operation box is used to start the processor after the user clicks, and the result display box is used to display the liquid phase diffusion coefficient of the binary solution to the user; wherein the initial parameters include initial time, time step, number of shots, first concentration, second concentration and calibration concentration.

6. A fully automatic liquid phase diffusion coefficient measurement method based on a liquid core cylindrical lens, applied to the fully automatic liquid phase diffusion coefficient measurement device based on a liquid core cylindrical lens according to any one of claims 1 to 5, characterized in that: The fully automatic liquid phase diffusion coefficient measurement method based on the liquid core cylindrical lens comprises: Issuing a first control instruction; the first control instruction is used to control the parallel light beam generating component to start working, generate a collimated parallel light beam, and inject the collimated parallel light beam into the liquid core cylindrical lens; A second control instruction is issued based on the initial time, time step and number of shots input by the user; the second control instruction is used to control the image acquisition component to take multiple shots of the liquid core cylindrical lens incident by the collimated parallel light beam to obtain multiple diffusion images of the binary solution during diffusion; the initial time is the time to start taking the diffusion image, and the time step is the time interval between two adjacent shots of the diffusion image; Process each diffuse image separately to obtain the position of the thinnest beam width in each diffuse image; The liquid phase diffusion coefficient of the binary solution is calculated based on the position of the thinnest beam width in each diffusion image, the shooting time of each diffusion image, and the first concentration, the second concentration, and the calibration concentration input by the user.

7. The fully automatic liquid phase diffusion coefficient measurement method based on liquid core cylindrical lens according to claim 6 is characterized in that: Each diffuse image is processed separately to obtain the position of the thinnest beam width in each diffuse image, including: For each diffusion image, denoising, brightness adjustment and binarization are performed on the diffusion image to obtain a binarized image; in the binarized image, the pixel points corresponding to the light beam are of a first color, and the pixel points corresponding to the background other than the light beam are of a second color; Traversing each column of pixels in the binary image, extracting the number of pixels of the first color in each column of pixels, and obtaining the beam width corresponding to each column of pixels; The minimum value of all the beam widths is selected as the thinnest beam width, and the number of pixel columns corresponding to the thinnest beam width is recorded to obtain the position of the thinnest beam width in the diffuse image.

8. The fully automatic liquid phase diffusion coefficient measurement method based on liquid core cylindrical lens according to claim 6 is characterized in that: Based on the position of the thinnest beam width in each diffusion image, the shooting time of each diffusion image, and the first concentration, the second concentration, and the calibration concentration input by the user, the liquid phase diffusion coefficient of the binary solution is calculated, specifically including: Taking the square root of the shooting time as the independent variable and the position of the thinnest beam width as the dependent variable, a linear fitting is performed based on the position of the thinnest beam width in each diffusion image and the shooting time of each diffusion image to obtain a linear fitting equation; The liquid phase diffusion coefficient of the binary solution is calculated based on the slope of the linear fitting equation and the first concentration, the second concentration and the calibration concentration input by the user.

9. The fully automatic liquid phase diffusion coefficient measurement method based on liquid core cylindrical lens according to claim 8, characterized in that: The calculation formula of liquid phase diffusion coefficient is: Wherein, D is the liquid phase diffusion coefficient; k is the slope of the linear fitting equation; erfinv is the inverse error function; C(Z, t) is the calibration concentration, Z is the position of the thinnest beam width, t is the time; C1 is the first concentration; C2 is the second concentration.

10. The fully automatic liquid phase diffusion coefficient measurement method based on liquid core cylindrical lens according to claim 6, characterized in that: The initial time is 1200s.

Images