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

Abstract

The application discloses a kind of full-automatic liquid-phase diffusion coefficient measuring device and method based on liquid-core column lens, it is related to liquid-phase mass transfer technical field, the measuring device includes parallel light beam generating component, liquid-core column lens, image acquisition component and processor, work by the processor control parallel light beam generating component starts, collimated parallel light beam is incident to liquid-core column lens, work by the processor control image acquisition component, automatically collect and obtain multiple diffusion images in the diffusion process of binary solution, by the processor respectively to each diffusion image is handled, obtain the position of the thinnest light beam width in each diffusion image, and combine the shooting time of each diffusion image and the first concentration, second concentration and calibration concentration input by user, calculate and obtain the liquid-phase diffusion coefficient of binary solution.The application can automatically complete the measurement of liquid-phase diffusion coefficient, be applicable to non-professional personnel, and can shorten the measurement time, improve measurement accuracy.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of liquid mass transfer, in particular to a full-automatic liquid diffusion coefficient measuring device and method based on a liquid core cylindrical lens. BACKGROUND

[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 under the action of no external force, and is an important parameter for studying mass transfer processes and calculating mass transfer rates, and can provide important basic data for the fields of biomedicine, environmental protection, physical and chemical engineering, scientific research and teaching, and therefore the measurement method for measuring the liquid diffusion coefficient through experiments is particularly concerned and valued by people, and common measurement methods include a membrane cell method, a Taylor dispersion method and an optical interference method, but these measurement methods cannot visually observe the diffusion process of the binary solution, have slow measurement speed and high requirements for the stability of instruments.

[0003] In order to solve the problems existing in the above three measurement methods, the present application provides a liquid diffusion coefficient measurement method based on a liquid core cylindrical lens, which can capture multiple diffusion images in the diffusion process, that is, visually observe the diffusion process of the binary solution, but the measurement method needs manual control of the diffusion image shooting process, manual processing of the diffusion images, extraction of the same width position of the multiple diffusion images, manual calculation of the liquid diffusion coefficient based on the same width position of the multiple diffusion images and the second Fick's law, so that the measurement needs the participation of professional personnel, and it is difficult for non-professionals to measure, and the extraction of the same width position and the calculation of the liquid diffusion coefficient by manual operation will lead to long measurement time, poor measurement precision, great influence of human factors, and the same diffusion image may have multiple width positions, so that the extraction of the same width position of the multiple diffusion images will affect the subsequent calculation, further leading to poor measurement precision. SUMMARY

[0004] The purpose of the present application is to provide a full-automatic liquid diffusion coefficient measuring device and method based on a liquid core cylindrical lens, which can automatically complete the measurement of the liquid diffusion coefficient, is suitable for non-professionals, can shorten the measurement time, improve the measurement precision, and provides convenience for the application and popularization of the instrument.

[0005] To achieve the above purpose, the present application provides the following solutions.

[0006] In a first aspect, the present application provides a full-automatic liquid diffusion coefficient measuring device based on a liquid core cylindrical lens, which comprises:

[0007] a parallel light beam generating component configured to generate a collimated parallel light beam and to cause the collimated parallel light beam to be incident on the liquid cylindrical lens;

[0008] The liquid cylindrical lens is filled with a binary solution; the binary solution comprises 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 configured to take multiple shots of the liquid cylindrical lens that is incident on the collimated parallel light beam to obtain multiple diffusion images in a diffusion process of the binary solution; a light beam width at any transverse position in the diffusion image corresponds to a solution concentration at a height corresponding to the transverse position in the liquid cylindrical lens.

[0010] a processor in communication connection with the parallel light beam generating component and the image acquisition component respectively, configured to control the parallel light beam generating component to start working, control the image acquisition component to work based on an initial time, a time step and a number of shots input by a user, process each diffusion image respectively to obtain a position of a thinnest light beam width in each diffusion image, and calculate a liquid phase diffusion coefficient of the binary solution based on the position of the thinnest light beam width in each diffusion image, a shooting time of each diffusion image, and a first concentration, a second concentration and a calibration concentration input by the user; wherein the initial time is a time at which the shooting of the diffusion image starts, the time step is a time interval between adjacent two times of shooting the diffusion image, and the calibration concentration corresponds to the thinnest light beam width.

[0011] In a second aspect, the present application provides a full-automatic liquid phase diffusion coefficient measurement method based on a liquid cylindrical lens, applied to the full-automatic liquid phase diffusion coefficient measurement device based on a liquid cylindrical lens described above, and the full-automatic liquid phase diffusion coefficient measurement method based on a liquid cylindrical lens comprises:

[0012] a first control instruction is sent; the first control instruction is used to control the parallel light beam generating component to start working, generate a collimated parallel light beam, and cause the collimated parallel light beam to be incident on the liquid cylindrical lens;

[0013] a second control instruction is sent based on an initial time, a time step and a number of shots input by a user; the second control instruction is used to control the image acquisition component to work, take multiple shots of the liquid cylindrical lens that is incident on the collimated parallel light beam to obtain multiple diffusion images in a diffusion process of the binary solution; the initial time is a time at which the shooting of the diffusion image starts, and the time step is a time interval between adjacent two times of shooting the diffusion image.

[0014] each diffusion image is processed respectively to obtain a position of a thinnest light beam width in each diffusion image.

[0015] 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.

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

[0017] The application provides a full-automatic liquid-phase diffusion coefficient measuring device and method based on a liquid-core cylindrical lens. The device comprises a parallel beam generating component, a liquid-core cylindrical lens, an image collecting component, and a processor. The processor controls the parallel beam generating component to start working, and the collimated parallel beam is incident to the liquid-core cylindrical lens. The processor controls the image collecting component to work, and the liquid-core cylindrical lens incident to the collimated parallel beam is photographed multiple times to obtain multiple diffusion images in the diffusion process of the binary solution. The processor processes each diffusion image to obtain the position of the thinnest beam width in each diffusion image. 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. The application only needs the user to input the initial time, the time step, the shooting number, the first concentration, the second concentration, and the calibration concentration. The processor can automatically complete the collection and processing of the diffusion images and the calculation of the liquid-phase diffusion coefficient, so that the measurement of the liquid-phase diffusion coefficient can be automatically completed. The whole measurement process does not need the participation of professional personnel and is suitable for non-professional personnel. Compared with the manual extraction of the same width position and the calculation of the liquid-phase diffusion coefficient, the measurement time can be shortened, the measurement accuracy can be improved, and the position of the thinnest beam width is extracted. Only one position of the thinnest beam width is extracted from one diffusion image. Compared with the extraction of the same width position from multiple diffusion images, which may affect the subsequent calculation due to multiple positions of the same width, the measurement accuracy can be further improved, and the problem that the liquid-phase diffusion coefficient cannot be quickly and accurately measured and the measurement difficulty for non-professional personnel is high can be solved. BRIEF DESCRIPTION OF DRAWINGS

[0018] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed in the embodiments. Obviously, the drawings in the following description only constitute some embodiments of the application, and for those skilled in the art, other drawings can also be obtained without creative labor.

[0019] Figure 1 A structure diagram of a full-automatic liquid-phase diffusion coefficient measuring device based on a liquid-core cylindrical lens is provided for Embodiment 1 of the application.

[0020] Figure 2 The structural schematic diagram of the liquid core column lens provided for Embodiment 1 of the present application; wherein, Figure 2 (a) in the above is a real object diagram of the liquid core column lens, Figure 2 (b) in the above is a model diagram of the liquid core column lens.

[0021] Figure 3 The schematic diagram of the image formed after the collimated parallel light beam passes through the single uniform solution with refractive indexes n1, n2, n3, n4 and n5 respectively in the liquid core column lens provided for Embodiment 1 of the present application.

[0022] Figure 4 The flow chart of the calculation of the liquid phase diffusion coefficient provided for Embodiment 1 of the present application.

[0023] Figure 5 The schematic diagram of the man-machine interface of the liquid phase diffusion coefficient measurement software provided for Embodiment 1 of the present application.

[0024] Figure 6 The extraction schematic diagram of the position of the thinnest light beam width in the diffusion image of the potassium chloride solution provided for Embodiment 1 of the present application.

[0025] Figure 7 The extraction schematic diagram of the position of the thinnest light beam width in the diffusion image of the ethylene glycol solution provided for Embodiment 1 of the present application.

[0026] Figure 8 The measurement result schematic diagram of the liquid phase diffusion coefficient of the 0.33 mol / L potassium chloride solution and the 3 mol / L potassium chloride solution provided for Embodiment 1 of the present application.

[0027] Figure 9 The measurement result schematic diagram of the liquid phase diffusion coefficient of the pure water and the 100% pure ethylene glycol solution provided for Embodiment 1 of the present application.

[0028] Figure 10 The flow schematic diagram of a kind of full-automatic liquid phase diffusion coefficient measurement method based on liquid core column lens provided for Embodiment 2 of the present application.

[0029] Figure 11 The structural schematic diagram of a kind of computer equipment provided for Embodiment 3 of the present application.

[0030] Reference signs:

[0031] 1-laser; 2-attenuation sheet; 3-space filter; 4-converging lens; 5-width limiting slit; 6-liquid core column lens; 7-image acquisition component. DETAILED DESCRIPTION

[0032] With reference to the drawings of the embodiments of the present application, the technical solutions in the embodiments of the present application will be clearly and completely described. Obviously, the described embodiments are only a part of the embodiments of the present application, but not all the embodiments of the present application. Based on the embodiments of the present application, all the other embodiments obtained by those skilled in the art without creative work fall within the scope of the present application.

[0033] Embodiment 1

[0034] The present embodiment is used to provide a full-automatic liquid-phase diffusion coefficient measuring device based on a liquid-core cylindrical lens, as shown in the accompanying drawings. Figure 1 The full-automatic liquid-phase diffusion coefficient measuring device based on a liquid-core cylindrical lens comprises:

[0035] A parallel light beam generating component is configured 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 internally filled with a binary solution, which comprises 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 being injected, 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] An image acquisition component 7 is configured to take multiple shots of the liquid-core cylindrical lens 6 incident on the collimated parallel light beam to obtain multiple diffusion images in a diffusion process of the binary solution, and the light beam width of any transverse position in the diffusion image corresponds to the solution concentration at the height corresponding to the transverse position in the liquid-core cylindrical lens 6.

[0038] A processor is communicatively connected with the parallel light beam generating component and the image acquisition component 7, respectively, and is configured to control the parallel light beam generating component to start working, to control the image acquisition component 7 to work based on an initial time, a time step and a number of shots input by a user, to process each diffusion image respectively to obtain the position of the thinnest light beam width in each diffusion image, and to calculate 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 the first concentration, the second concentration and the calibration concentration input by the user. The initial time is the time at which the diffusion image starts to be shot, the time step is the time interval between adjacent two shots of the diffusion image, the number of shots can be 10-20 diffusion images, and the calibration concentration corresponds to the thinnest light beam width.

[0039] The parallel light beam generating component of the embodiment is used to first emit a monochromatic light beam, which is a kind of high-intensity, monochromatic and coherent light beam, such as a laser, and then perform corresponding processing on the monochromatic light beam to generate a collimated parallel light beam. At this time, the parallel light beam generating component can include a laser 1 and, arranged in sequence along the laser propagation direction, an attenuating sheet 2, a spatial filter 3, a converging lens 4 and a width-limiting slit 5. The laser 1 can be a semiconductor laser, which is used to emit a laser to provide a light source. The attenuating sheet 2 is used to attenuate the light intensity by using the light absorption characteristics of a substance. The spatial filter 3 and the converging lens 4 form a collimating and expanding assembly. The spatial filter 3 is used to filter out scattered light, stray light and other high-frequency information caused during transmission, and make the light beam output an ideal spherical wave as a point light source. The converging lens 4 converts the point light source into parallel light, that is, when the input point light source is at the focal point of the lens, the output is parallel light. The width-limiting slit 5 is used to limit the width of the light beam. The laser 1 emits a laser, which is attenuated by the attenuating sheet 2. The attenuated laser enters the spatial filter 3 to eliminate part of the stray light, that is, to filter out the stray light, forming a point light source. The point light source is then collimated and expanded into a parallel light by the converging lens 4, generating a collimated parallel light beam. The collimated parallel light beam enters the liquid core lens 6 through the width-limiting slit 5, and specifically enters the center position of the liquid core lens 6. After refraction by the liquid core lens 6, an image is formed on the image acquisition component 7, which is equivalent to being imaged by the image acquisition component 7 and being saved in real time, obtaining a diffusion image.

[0040] The liquid core lens 6 changes the propagation path of light by using the refractive index of the liquid, and realizes the measurement of the refractive index and the diffusion coefficient of the liquid, as shown in Figure 2 The liquid core lens 6 is composed of two negative meniscus cylindrical lenses (also known as negative meniscus lenses) and is used not only as a core imaging element but also as a diffusion cell for a binary solution. During measurement, a binary solution is filled into the liquid core lens 6, the binary solution including a first solution and a second solution, the first solution being located above the second solution and the first concentration of the first solution being less than the second concentration of the second solution. The collimated parallel light beam is incident on the curved surface of the liquid core lens 6.

[0041] In the embodiment, the image acquisition component 7 can be a CMOS (Complementary Metal-Oxide-Semiconductor) camera. The laser 1, the attenuating sheet 2, the collimating and expanding assembly, the width-limiting slit 5, the liquid core lens 6, the image acquisition component 7 and the processor are placed in sequence.

[0042] When different concentrations of solutions are injected into the liquid core lens 6, different concentrations will correspond to different refractive indices. At this time, when the collimated parallel light beam is imaged through the liquid core lens 6, an image with different light beam widths will be imaged on the image acquisition component 7, as shown in Figure 3As shown, different concentrations of solutions are injected into the liquid core column lens 6, which is equivalent to injecting solutions with different refractive indexes. Specifically, solutions with refractive indexes of n1, n2, n3, n4, and n5 are injected respectively, and images with different beam widths are obtained. Different refractive indexes n1, n2, n3, n4, and n5 correspond to different beam widths. Figure 3 The longitudinal direction is the height direction of the liquid core column lens 6, and the white line is the light beam. The width of the white line in the transverse direction is the beam width. Figure 3 Obviously, different concentrations correspond to different refractive indexes, and different refractive indexes correspond to different beam widths.

[0043] When a binary solution is injected into the liquid core column lens 6, different diffusion images are formed after imaging as the binary solution continuously diffuses. Since a concentration gradient is formed during the diffusion of the binary solution, the refractive indexes of the binary solution at different heights are also different. Therefore, the diffusion images have different beam widths. The beam width at any transverse position in the diffusion image corresponds to the concentration of the solution at the height corresponding to the transverse position in the liquid core column lens 6. The beam width is the width of the light beam in the longitudinal direction in the diffusion image.

[0044] In this embodiment, the processor can be a host computer. In order to realize full-automatic measurement, the processor is installed with liquid phase diffusion coefficient measurement software. Diffusion images are collected by the image collection component 7 and analyzed and calculated by the liquid phase diffusion coefficient measurement software to obtain the liquid phase diffusion coefficient. The liquid phase diffusion coefficient measurement software includes a light beam generation module, an image collection module, an image processing module and a liquid phase diffusion coefficient calculation module. The light beam generation module is used to control the parallel light beam generation component to start working, generate a collimated parallel light beam, and make the collimated parallel light beam incident to the liquid core column lens 6. The image collection module collects diffusion images in real time. The specific parameter settings include setting the name of the image collection component 7, the time step between diffusion images and the saving position of diffusion images. Specifically, the image collection component 7 is controlled to work based on the initial time, time step and number of shots input by the user, the liquid core column lens 6 is shot multiple times after being incident to the collimated parallel light beam, and multiple diffusion images in the diffusion process of the binary solution are obtained. The image processing module is used to process each diffusion image respectively to obtain the position of the thinnest light beam width in each diffusion image, so as to extract the 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 concentration of the calibration solution (the calibration concentration), the initial time and the time step. Specifically, 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.

[0045] In order to measure the liquid phase diffusion coefficient, the calibration concentration solution is injected into the liquid core column lens 6 in advance in this embodiment. When the image collection component 7 moves to the focal plane position of the liquid core column lens 6, the collection plane of the image collection component 7 receives an image with a straight line that is thin and has the same width at this time, that is, the collimated parallel light beam converges 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 collection component 7 is continuously adjusted until the light beam width in the obtained image is thinnest. Therefore, in this embodiment, the distance between the liquid core column lens 6 and the image collection component 7 is determined according to a preset principle. The preset principle is that the calibration concentration corresponds to the thinnest light beam width. The concentration corresponding to the thinnest light beam width in the diffusion image can be determined as the calibration concentration when the diffusion is performed subsequently.

[0046] In order to improve the measurement accuracy, the difference between the calibration concentration and the first concentration is less than a preset value. The preset value can be determined according to user demand. The target is to make the calibration concentration and the first concentration as close as possible, so as to improve the measurement accuracy.

[0047] As shown in Figure 4 The processor is connected to the image acquisition component 7, sets the time interval and the saving position of each diffusion image in the image acquisition module based on the initial time, the time step and the number of shots input by the user, and acquires the diffusion images at multiple time points in real time. Considering the convection and other factors after the binary solution is injected, the binary solution is unstable and needs to be waited for a certain time before it can be stabilized, so 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 the user's needs.

[0048] After the real-time acquisition of the diffusion images is completed through the image acquisition module, all the acquired diffusion images enter the image processing module, the image processing module extracts the feature of the position of the thinnest light beam width from the diffusion images, and saves the position of the thinnest light beam width as a CSV file in real time. At this time, each diffusion image is processed respectively to obtain the position of the thinnest light beam width in each diffusion image, which specifically includes: for each diffusion image, denoising, brightness adjustment and binarization processing are performed on the diffusion image to obtain a binarized image, the pixel points corresponding to the light beam in the binarized image are a first color, and the pixel points corresponding to the background other than the light beam are a second color; each column of pixel points in the binarized image is traversed, the number of pixel points of the first color in each column of pixel points is extracted, and the light beam width corresponding to each column of pixel points is obtained; the minimum value of all the light beam widths is selected as the thinnest light beam width, and the column number of the pixel points corresponding to the thinnest light beam width is recorded to obtain the position of the thinnest light beam width in the diffusion image, so as to extract the feature of the diffusion image, and read the thin layer position of each diffusion image, which is the position of the thinnest light beam width.

[0049] The liquid phase diffusion coefficient calculation module is started, the user inputs 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 the run 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 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, the liquid phase diffusion coefficient of the binary solution is calculated, which specifically includes: taking the square root of the shooting time as the independent variable and the position of the thinnest light beam width as the dependent variable, linear fitting is performed based on the position of the thinnest light beam width in each diffusion image and the shooting time of each shot image to obtain a linear fitting equation, and the curve of the thin layer position Z and can be drawn in the process of linear fitting; the slope of the linear fitting equation and the first concentration, the second concentration and the calibration concentration input by the user are used to calculate the liquid phase diffusion coefficient of the binary solution.

[0050] According to the diffusion equation of binary solution, a concentration distribution function can be obtained by combining initial condition and boundary condition, and 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 time; D is the liquid phase diffusion coefficient of binary solution.

[0053] The initial condition is:

[0054]

[0055] wherein x is the lateral position of the diffusion image; C1 is the first concentration; C2 is the second concentration.

[0056] The boundary condition is:

[0057]

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

[0059]

[0060] wherein erf is the error function.

[0061] The above formula is the position-time relationship of concentration after the binary solution diffuses for a certain time, and let erfinv be the inverse error function, then the above formula can be rewritten as:

[0062]

[0063] wherein erfinv is the inverse error function.

[0064] Square and move the term of the above formula, and further deduce to obtain:

[0065]

[0066] By selecting the calibration concentration, the first concentration and the second concentration, and fitting the relationship between Z and , the liquid phase diffusion coefficient can be calculated according to the above formula.

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

[0068]

[0069] 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 narrowest beam width, t is the time; C1 is the first concentration; C2 is the second concentration.

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

[0071] The collimated parallel light beam is imaged on the image acquisition component 7 by the liquid core lens 6 to obtain the diffusion image of the binary solution, the diffusion image is collected in real time by the liquid phase diffusion coefficient measurement software, the diffusion image is automatically processed to obtain the fitting curve of the position of the narrowest beam width and the time and the linear fitting equation, and the liquid phase diffusion coefficient is further calculated, the user inputs 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, so that the liquid phase diffusion coefficient can be calculated one key, the required liquid phase diffusion coefficient is quickly obtained, the diffusion image of the binary solution is obtained in real time by the liquid core lens 6 and the liquid phase diffusion coefficient measurement software, and the automatic measurement of the liquid phase diffusion coefficient is carried out by feature extraction of the diffusion image, the full-automatic liquid phase diffusion coefficient measurement device has the characteristics of simple operation, accurate measurement and short measurement time.

[0072] Currently, there is no dedicated device for measuring the diffusion coefficient of liquid phases; therefore, the invention of a fully automated liquid phase diffusion coefficient measuring device is essential. This embodiment discloses a fully automated liquid phase diffusion coefficient measuring device based on a liquid-core lens, relating to the field of measuring the liquid phase diffusion coefficient of binary solutions. The measuring device sequentially includes: a laser 1, an attenuator 2, a spatial filter 3, a converging lens 4, a width-limiting slit 5, a liquid-core lens 6, an image acquisition unit 7, a processor, and liquid phase diffusion coefficient measurement software. The laser 1 emits a laser beam, which passes through the attenuator 2, spatial filter 3, converging lens 4, and width-limiting slit 5 to form a collimated parallel beam. This collimated parallel beam is then imaged onto the image acquisition unit 7 by the liquid-core lens 6 to obtain a diffusion image of the binary solution. The image is then processed by the fully automated liquid phase diffusion coefficient measuring device and combined with… A software program for automatically measuring the liquid diffusion coefficient was developed based on the feature processing of diffusion images. This software can acquire diffusion images in real time, extract features from the acquired diffusion images, and then automatically calculate the liquid diffusion coefficient. Using this software can reduce reading errors caused by human factors, greatly shorten the measurement time, and develop a human-computer interaction interface. By using this fully automatic liquid diffusion coefficient measuring device, not only can the liquid diffusion coefficient of binary solutions be measured accurately and quickly, but non-professionals can also measure the liquid diffusion coefficient quickly and accurately.

[0073] This embodiment mainly uses... Figure 1 The fully automatic liquid diffusion coefficient measuring device shown acquires diffusion images at different times. By observing the change in the position of the narrowest beam width in the diffusion image over time, the liquid diffusion coefficient is automatically calculated by the liquid diffusion coefficient measuring software. In the following embodiment, the diffusion coefficients of potassium chloride aqueous solution and ethylene glycol aqueous solution are calculated using the fully automatic liquid diffusion coefficient measuring device.

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

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

[0076] The fully automated liquid diffusion coefficient measuring device used in this example is as follows: Figure 1As shown, it is divided into five parts: 1) the light source assembly composed of a low-power semiconductor laser with a wavelength of 589 nm and a maximum power of 20 mw and an attenuator 2, emitting a monochromatic laser beam; 2) the collimating and expanding assembly composed of a 40 times microscope objective, a spatial filter 3 with a pinhole aperture of 15 μm, and a converging lens 4 with a focal length of 500 mm, which collimates and expands the monochromatic laser beam to obtain a collimated parallel light beam; 3) a width-adjustable width-limiting slit 5 as a width-limiting element of the collimated parallel light 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 4090×3072 pixels and a pixel size of 5.5×5.5 microns.

[0077] (2) Configuration of the required solution

[0078] At room temperature (25℃), the test solution was prepared by using pure ethylene glycol solution, 99.9% potassium chloride solid particles and pure water. In this example, the test solution was: 0.33 mol / L potassium chloride solution and 3 mol / L potassium chloride solution, this group of binary solutions, pure water and 100% pure ethylene glycol solution, this group of binary solutions. The concentration corresponding to the test solution is the upper liquid concentration and the lower liquid concentration required to be input by the human-computer interaction interface. For example, for the diffusion system of 0.33 mol / L potassium chloride solution and 3 mol / L potassium chloride solution, the upper liquid concentration is the concentration of 0.33 mol / L potassium chloride solution, and the lower liquid concentration is the concentration of 3 mol / L potassium chloride solution. For the diffusion system 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℃), 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 and sharp bright line, that is, the light beam width is the thinnest at this time. For the diffusion system of 0.33 mol / L potassium chloride solution and 3 mol / L potassium chloride solution, 0.487 mol / L potassium chloride solution is used for calibration. For the diffusion system of pure water and 100% pure ethylene glycol solution, 5% ethylene glycol solution is used for calibration.

[0080] The refractive index n of the test solution was measured by an Abbe refractometer with a precision of 0.0002. The relationship between the prepared solution and the refractive index is shown in Table 1.

[0081] Table 1 Relationship between prepared solution and 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 water solution 1.3333 3 mol / L potassium chloride 1.3600 100% pure ethylene glycol solution 1.4296 0.487 mol / L potassium chloride 1.3376 5% ethylene glycol solution 1.3389

[0083] With the progress of binary diffusion process, the function relationship between the position of the thinnest light beam width and time is obtained by feature extraction of the thinnest light beam width at the refractive index position of the calibration solution, and the liquid phase diffusion coefficient of the binary solution can be calculated.

[0084] (3) The full-automatic liquid phase diffusion coefficient measuring device is sequentially composed of a semiconductor laser, an attenuator 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, and after the required solution is configured, the liquid phase diffusion coefficient measuring software is started, and the initial time, the time step, the number of shots, the diffusion image storage position and the like are input, so that the diffusion image is collected in real time.

[0085] (4) According to the image characteristics of the liquid phase diffusion coefficient measurement, the collected diffusion image is processed by the image processing module of the liquid phase diffusion coefficient measurement software through the means of denoising, brightness processing and binarization processing.

[0086] (5) The diffusion image after processing is extracted, and since the 0.487 mol / L potassium chloride solution is used for calibration, the features extracted in this example include: the position corresponding to the refractive index of 1.3376 of the 0.487 mol / L potassium chloride solution, that is, the position of the thinnest light beam width of the diffusion image is extracted, as shown in FIG. 5, the intersection of the red line and the white line in the diffusion image is the feature position (i.e. the position of the thinnest light beam width), and since the 5% ethylene glycol solution is used for calibration, the features extracted in this example include: the position corresponding to the refractive index of 1.3389 of the 5% ethylene glycol solution, that is, the position of the thinnest light beam width of the diffusion image is extracted, as shown in FIG. 6, the intersection of the red line and the white line in the diffusion image is the feature position, Figure 6 Figure 7 and Figure 6 and Figure 7 are only example images of this embodiment, and multiple diffusion images need to be processed during the measurement process.

[0087] (6) After the image processing module completes the image processing process, the liquid phase diffusion coefficient is automatically calculated by the liquid phase diffusion coefficient calculation module, the upper liquid concentration, the lower liquid concentration, the calibration concentration, the initial time, the time step are input in the man-machine interaction interface of the liquid phase diffusion coefficient measurement software, and the measurement result of the liquid phase diffusion coefficient can be obtained by clicking the running calculation, and the relationship between the thin layer position and the time is obtained, as shown in FIG. 7 and FIG. 8. Figure 8 and Figure 9 .

[0088] The liquid phase diffusion coefficients of the two groups of binary solutions obtained by the liquid phase diffusion coefficient measurement software for the group of binary solutions of 0.33 mol / L potassium chloride solution and 3 mol / L potassium chloride solution and the group of binary solutions of pure water and 100% pure ethylene glycol solution 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 the existing literature.

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

[0093] The embodiment provides an instrument for automatically measuring a liquid phase diffusion coefficient based on a liquid core column lens 6. A binary solution diffusion image is obtained by using a lens imaging method. After a collimated parallel light beam passes through the liquid core column lens 6, a diffusion image is formed on a focal plane. Through automatic acquisition of the diffusion image, automatic extraction of a thin layer position, and automatic measurement of the liquid phase diffusion coefficient, the measurement operation becomes simpler, the calculation result is more accurate, non-professionals can also realize measurement of the liquid phase diffusion coefficient, the time required for measuring the liquid phase diffusion coefficient is greatly shortened, and the work efficiency is significantly improved.

[0094] Embodiment 2

[0095] The embodiment provides a full-automatic liquid phase diffusion coefficient measurement method based on a liquid core column lens, which is applied to the full-automatic liquid phase diffusion coefficient measurement device based on the liquid core column lens described in Embodiment 1, as shown in the figure, the full-automatic liquid phase diffusion coefficient measurement method based on the liquid core column lens comprises the following steps. Figure 10

[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 to the liquid core column lens.

[0097] S2: issuing a second control instruction based on an initial time, a time step and a number of photographs input by a user; the second control instruction is used to control the image acquisition component to work, photograph the liquid core column lens incident to the collimated parallel light beam multiple times, and obtain multiple diffusion images in a binary solution diffusion process; the initial time is a time for starting to photograph the diffusion images, and the time step is a time interval between adjacent two times of photographing the diffusion images.

[0098] S3: processing each diffusion image respectively to obtain a position of a thinnest light beam width in each diffusion image.

[0099] ​S4: calculating 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] The position of the thinnest beam width in each diffusion image is obtained by processing each diffusion image, specifically including: for each diffusion image, performing denoising, brightness adjustment processing, and binarization processing on the diffusion image to obtain a binarization image, wherein the pixel points corresponding to the light beam in the binarization image 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 pixel points in the binarization image, extracting the number of pixel points of the first color in each column of pixel points to obtain 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 pixel point column corresponding to the thinnest beam width to obtain the position of the thinnest beam width in the diffusion image.

[0101] 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, 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, 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; and taking the slope of the linear fitting equation and the first concentration, the second concentration, and the calibration concentration input by the user to calculate the liquid-phase diffusion coefficient of the binary solution.

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

[0103]

[0104] 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, and t is the time; C1 is the first concentration; and C2 is the second concentration.

[0105] The initial time is 1200s.

[0106] Example 3

[0107] In an exemplary embodiment, a computer device, which can be a server or a terminal, is provided, and an internal structure diagram of the computer device can be as shown in FIG. 1. Figure 11As shown in the figure. The computer device includes a processor, a memory, an input / output interface (Input / Output, referred to as I / O) and a communication interface. Among them, the processor, the memory and the input / output interface are connected through the system bus, and the communication interface is connected to the system bus through the input / output interface. Among them, the processor of the computer device is used to provide computing and control capability. 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 the external device. The communication interface of the computer device is used to communicate with the terminal outside through the network connection. The computer program is executed by the processor to realize a kind of full-automatic liquid-phase diffusion coefficient measurement method based on liquid core column lens.

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

[0109] In one exemplary embodiment, a computer device is provided, comprising a memory and a processor, the memory stores a computer program, and the processor executes the computer program to realize the full-automatic liquid-phase diffusion coefficient measurement method based on liquid core column lens in embodiment 2.

[0110] Embodiment 4

[0111] In one exemplary embodiment, a computer readable storage medium is provided, which stores a computer program, and the computer program is executed by a processor to realize the full-automatic liquid-phase diffusion coefficient measurement method based on liquid core column lens in embodiment 2.

[0112] Embodiment 5

[0113] In one exemplary embodiment, a computer program product is provided, comprising a computer program, and the computer program is executed by a processor to realize the full-automatic liquid-phase diffusion coefficient measurement method based on liquid core column lens in embodiment 2.

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

[0115] Any combination of the technical features of the above embodiments can be made. In order to make the description simple, all possible combinations of the technical features in the above embodiments are not described, but as long as the combination of the technical features does not exist, it should be considered as the scope of the present application.

[0116] The principles and implementation modes of the present application are described by applying specific examples herein, and the above embodiment description is only used to help understand the method and its core idea of the present application; at the same time, for those skilled in the art, according to the idea of the present application, the specific implementation mode and application range will be changed. In view of the above, the content of the present application should not be understood as a limitation.

Claims

1. A full-automatic liquid-phase diffusion coefficient measuring device based on liquid-core column lens, characterized in that, The full-automatic liquid-phase diffusion coefficient measuring device based on a liquid-core column lens comprises: a parallel light beam generating component for generating a collimated parallel light beam and making the collimated parallel light beam incident to a liquid-core column lens; the liquid-core column lens is internally filled with a binary solution; the binary solution comprises 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 collecting component for taking multiple shots of the liquid-core column lens incident to the collimated parallel light beam to obtain multiple diffusion images in a diffusion process of the binary solution; a light beam width of any transverse position in the diffusion image corresponds to a solution concentration at a height corresponding to the transverse position in the liquid-core column lens; a processor in communication connection with the parallel light beam generating component and the image collecting component respectively, for controlling the parallel light beam generating component to start working, controlling the image collecting 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 a position of a thinnest light beam width in each diffusion image, and calculating a liquid-phase diffusion coefficient of the binary solution based on the position of the thinnest light beam width in each diffusion image, a shooting time of each diffusion image and a first concentration, a second concentration and a calibration concentration input by the user; wherein the initial time is a time of starting to shoot the diffusion images, the time step is a time interval of adjacent two times of shooting the diffusion images, and the calibration concentration corresponds to the thinnest light beam width.

2. The liquid-core-column-lens-based fully-automatic liquid-phase diffusion coefficient measurement apparatus according to claim 1, wherein The parallel light beam generating component comprises a laser, an attenuation sheet, a spatial filter, a converging lens and a width-limiting slit arranged in sequence along a laser propagation direction.

3. The liquid-core-column-lens-based fully automated liquid-phase diffusion coefficient measurement apparatus according to claim 1, wherein A distance between the liquid-core column lens and the image collecting 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 liquid-core-column-lens-based fully automated liquid-phase diffusion coefficient measurement apparatus according to claim 1, wherein A difference between the calibration concentration and the first concentration is less than a preset value.

5. The liquid-core-column-lens-based fully automated liquid-phase diffusion coefficient measurement apparatus according to claim 1, wherein The processor has a human-computer interaction interface, the human-computer interaction interface comprises an input box, a running box and a result display box, the input box is used for inputting initial parameters by a user, the running box is used for starting the processor after being clicked by the user, and the result display box is used for showing the liquid-phase diffusion coefficient of the binary solution to the user; wherein the initial parameters comprise the initial time, the time step, the number of shots, the first concentration, the second concentration and the calibration concentration.

6. A full-automatic liquid-phase diffusion coefficient measuring method based on liquid-core column lens, using the full-automatic liquid-phase diffusion coefficient measuring device based on liquid-core column lens according to any one of claims 1-5, characterized in that, The full-automatic liquid-phase diffusion coefficient measuring method based on the liquid-core column lens comprises: sending a first control instruction; the first control instruction is used for controlling the parallel light beam generating component to start working, generating a collimated parallel light beam, and making the collimated parallel light beam incident to a liquid-core column lens; issuing a second control instruction based on the initial time, the time step and the number of shots input by the user; the second control instruction is used to control the image acquisition component to work, and the liquid-core cylindrical lens irradiated by the collimated parallel light beam is shot multiple times to obtain multiple diffusion images in the binary solution diffusion process; the initial time is the time at which the diffusion image is started to be shot, and the time step is the time interval between adjacent two times of shooting the diffusion image; processing each diffusion image respectively to obtain the position of the thinnest light beam width in each diffusion image; 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 the first concentration, the second concentration and the calibration concentration input by the user.

7. The liquid-core-column-lens-based fully automated liquid-phase diffusion coefficient measurement method according to claim 6, wherein, processing each diffusion image respectively to obtain the position of the thinnest light beam width in each diffusion image, specifically including: for each diffusion image, performing denoising, brightness adjustment processing and binarization processing on the diffusion image to obtain a binarized image; the pixel points corresponding to the light beam in the binarized image 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 pixel points in the binarized image, extracting the number of pixel points of the first color in each column of pixel points to obtain the light beam width corresponding to each column of pixel points; selecting the minimum value of all the light beam widths as the thinnest light beam width, and recording the pixel point column corresponding to the thinnest light beam width to obtain the position of the thinnest light beam width in the diffusion image.

8. The liquid-core-column-lens-based fully automated liquid-phase diffusion coefficient measurement method according to claim 6, wherein, 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 the first concentration, the second concentration and the calibration concentration input by the user, specifically including: taking the square root of the shooting time as the independent variable and the position of the thinnest light beam width as the dependent variable, performing linear fitting based on the position of the thinnest light beam width in each diffusion image and the shooting time of each diffusion image to obtain a linear fitting equation; calculating the liquid-phase diffusion coefficient of the binary solution 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 liquid-core-column-lens-based fully automated liquid-phase diffusion coefficient measurement method according to claim 8, wherein, The formula for calculating the liquid-phase diffusion coefficient is: ； wherein, is the liquid phase diffusion coefficient; is the slope of the linear fit equation; is the inverse error function; is the calibration concentration, is the position of the narrowest beam width, is time; is the first concentration; is the second concentration.

10. The liquid-core-column-lens-based fully automated liquid-phase diffusion coefficient measurement method according to claim 6, wherein, The initial time is 1200s.

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