Road lime soil content rapid titration detection end point judgment device and use method thereof

Abstract

The invention relates to the technical field of EDTA (Ethylene Diamine Tetraacetic Acid) titration, in particular to a road lime soil content rapid titration detection end point judgment device and a use method thereof. The suction cup is matched with the band-pass optical filter and the photoresistor, so that the resistance value of the photoresistor can be changed along with the color change of a solution to be detected, the real-time current displayed by the ampere meter is changed, and when the difference percentage of the real-time current and the comparison current is observed to be less than 10%, the titration experiment reaches the titration end point; the detachable suction cup is matched with the protrusion and the clamping groove, so that the band-pass optical filter is convenient to replace, and it is guaranteed that the position of the band-pass optical filter and the position of the photoresistor are always relatively fixed so as to control variables. According to the method, the appropriate optical filter is selected to be matched with the titration experiment, optical signals are converted into electric signals for objective characterization by utilizing optical characteristics of the optical filter and the photoresistor, subjective errors of end point judgment of the titration experiment are eliminated, and the accuracy of the experiment is ensured while a part of labor force is saved.

Description

Technical Field

[0001] The invention relates to the technical field of EDTA titration, and in particular to a device for determining an endpoint of a rapid titration detection of road dust content and a method for using the device. Background Art

[0002] EDTA titration is widely used to detect the content of road dust due to its advantages such as good reproducibility, simplicity and speed, low equipment cost, and easy mastery. The content of road dust is generally obtained by determining the consumption of titration solution at the titration endpoint. However, the judgment of the titration endpoint usually involves visual observation of the color change of the sample to be tested. It is necessary to carefully observe the color of the sample to be tested each time after the sample to be tested is stable. Due to differences in color perception among operators, this process usually produces subjective errors, thereby affecting the experimental results.

[0003] The color discrimination device currently used is a color sensor. The traditional color sensor can quickly determine the type of color, but the device will be affected by the surrounding light environment when measuring color, and it cannot determine the endpoint of the titration experiment through linear calculation. At the same time, under certain specific color combinations, the color sensor cannot accurately distinguish the colors, so the color sensor cannot be directly used to determine the titration endpoint. Summary of the invention

[0004] In view of the deficiencies in the prior art, the present invention provides a device for determining an endpoint of a rapid titration detection of road dust content and a method for using the device, which solves the problem that it is difficult to accurately determine the color change of the titration endpoint by using a color sensor or observing with the human eye.

[0005] To achieve the above object, the present invention provides the following technical solutions:

[0006] The endpoint judgment device for rapid titration detection of road dust content includes a data processing module for collecting and displaying electrical signals, and a photoelectric conversion module for collecting optical signals in a solution and converting them into electrical signals;

[0007] The photoelectric conversion module includes an opaque protective hose, a suction cup for adsorbing on the bottom of a reaction container is arranged at the end of the protective hose, a bandpass filter that only allows light signals of a specific wavelength band to pass through is arranged in the suction cup, and a photoresistor that converts the light signal processed by the bandpass filter into an electrical signal and transmits it to the data processing module is arranged in the protective hose.

[0008] Preferably, the data processing module includes a box as an installation carrier, an ammeter for detecting the current passing through the photoresistor is arranged in the box, a power supply for forming a loop with the ammeter and the photoresistor is also arranged in the box, and a switch for controlling the on and off of the loop is arranged on the surface of the box.

[0009] Preferably, a connecting tube for inserting into the end of the protective hose is provided at the bottom of the suction cup, and the light signal processed by the bandpass filter can be captured by the photoresistor through the connecting tube. A protrusion is provided at the end of the connecting tube, and a card slot for cooperating and fixing with the protrusion is provided at the end of the protective hose.

[0010] Preferably, the mouth of the suction cup is provided with a detachable opaque protective cover.

[0011] The present invention also provides a device for determining the endpoint of rapid titration detection of road dust content and a method for using the device, the method comprising the following steps:

[0012] S1. Determine the initial color of the solution to be tested in the titration experiment and the color of the solution at the endpoint of the titration experiment, and select a bandpass filter corresponding to the initial color;

[0013] S2. Prepare a colorimetric solution with the same color as the endpoint solution of the titration experiment according to the standard specification, and attach the suction cup to the bottom of the container containing the colorimetric solution, turn on the switch, and obtain the comparison current;

[0014] S3, adsorb the suction cup to the bottom of the container containing the supernatant of the solution to be tested, turn on the switch, and then continuously drip the titration solution into the supernatant of the solution to be tested, and observe the real-time current;

[0015] S4, calculating the current difference percentage between the real-time current and the comparison current, and determining whether the current difference percentage is within the current difference threshold;

[0016] If not, return to step S3;

[0017] If yes, stop the titration and record the consumption of titration solution;

[0018] S5. Turn off the endpoint determination device for the rapid titration detection of road dust content.

[0019] Preferably, in step S2, the following steps are specifically included:

[0020] S21. Prepare the relevant reagents for preparing the colorimetric solution according to the standard specifications, including: distilled water, buffer and indicator;

[0021] S22, adding z milliliters of distilled water, a milliliters of buffer and b grams of indicator into the container to prepare a colorimetric solution;

[0022] in:

[0023] z=l1+l2+l3

[0024] In the above formula, l1 is the amount of the clear solution of the sample to be tested after treatment in the titration experiment in the standard specification, l2 is the amount of distilled water added to dilute the supernatant in the titration experiment in the standard specification, l3 is the amount of other liquid reagents added in the titration experiment in the standard specification, a is the amount of buffer added in the titration experiment in the standard specification; b is the amount of indicator added in the standard specification;

[0025] S23, adsorbing the suction cup to the bottom of the container containing the colorimetric solution to obtain the corresponding comparison current.

[0026] Preferably, in step S4, the current difference percentage is calculated as follows:

[0027]

[0028] In the above formula, ω represents the current difference percentage, I i It represents the real-time current during the i-th titration, and I1 is the comparison current.

[0029] Compared with the prior art, the present invention provides a device for determining the endpoint of rapid titration detection of road dust content and a method for using the device, which has the following beneficial effects:

[0030] 1. By setting the suction cup in combination with the bandpass filter and the photoresistor, the resistance of the photoresistor can change with the color of the solution during the titration experiment, so that the real-time current displayed by the ammeter changes, and the titration end point is determined by observing the real-time current, thereby eliminating the subjective error in the titration experiment, and the consumption of the titration solution can be obtained more accurately, thereby obtaining more accurate experimental results.

[0031] 2. The device disclosed in the present invention is specially used for the titration detection experiment of roadbed ash content. The endpoint of the titration experiment can be determined by linear calculation, avoiding the influence of lighting conditions, complex colors and control background on the detection results during the experiment, and improving the detection accuracy.

[0032] 3. By providing a detachable protective cover, light or foreign matter can be prevented from entering the photoelectric conversion module when the device is stored, and the filter and photoresistor can be protected from damage, thereby extending the service life of the device.

[0033] 4. The position of the bandpass filter and the position of the photoresistor in the present invention are always relatively fixed, which can achieve the purpose of controlling the variable. At the same time, the protrusion and the slot can facilitate the disassembly and replacement of the suction cup and the bandpass filter, thereby making the device more widely applicable. In addition, the device does not require high structural accuracy during the production process, and can achieve the purpose of rapid mass production. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] The drawings described herein are used to provide a further understanding of the present application and constitute a part of the present application. The illustrative embodiments of the present application and their descriptions are used to explain the present application and do not constitute an improper limitation on the present application. In the drawings:

[0035] Figure 1 It is a schematic diagram of the three-dimensional structure of the present invention;

[0036] Figure 2 is a cross-sectional schematic diagram of a data processing module of the present invention;

[0037] Figure 3 The present invention is a flow chart of a method for using the device for determining the endpoint of rapid titration detection of road dust content.

[0038] In the figure: 1. Photoelectric conversion module; 11. Protective hose; 12. Suction cup; 13. Bandpass filter; 14. Photoresistor; 15. Connecting tube; 16. Protrusion; 17. Card slot; 18. Protective cover; 2. Data processing module; 21. Box; 22. Ammeter; 23. Power supply; 24. Switch. DETAILED DESCRIPTION

[0039] The following will describe the implementation methods of the present application in detail with the help of accompanying drawings and examples, so that the implementation process of how the present application uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0040] In order to solve the problem that it is difficult to accurately determine the color change of the titration endpoint by color sensors or human eyes, the present invention provides a device for determining the endpoint of rapid titration detection of road dust content, such as Figure 1 and Figure 2 As shown, by converting the optical signal into an electrical signal, the color change in the solution is monitored, and the endpoint of the titration experiment is quantitatively determined according to the current change. The road dust content rapid titration detection endpoint judgment device includes a data processing module 2 for collecting and displaying electrical signals, and also includes a photoelectric conversion module 1 for collecting the optical signal in the solution and converting it into an electrical signal. In the titration experiment, the color of the solution will change as the titration experiment proceeds, so the color change can be converted into a current change by the photoelectric conversion module 1, so as to more accurately judge the endpoint of the titration experiment;

[0041] The photoelectric conversion module 1 includes a light-proof protective hose 11, and a suction cup 12 for adsorbing on the bottom of the reaction container is arranged at the end of the protective hose 11. Generally, the suction cup 12 is adsorbed on the bottom of the solution reaction container to prevent external light from entering the suction cup 12 to cause interference, so that the light in the suction cup 12 is all reflected or refracted light of the solution. A bandpass filter 13 is arranged in the suction cup 12, which only allows light signals of a specific band to pass through. The optical characteristics of the bandpass filter 13 are used to shield visible light of other bands, and the wavelength change of light is converted into the intensity change of light in disguise. A photoresistor 14 is arranged in the protective hose 11 to convert the light signal processed by the bandpass filter 13 into an electrical signal and transmit it to the data processing module 2. A wiring harness for electrical signal transmission is arranged inside the protective hose 11. At the same time, the protective hose can prevent external light from entering the device to ensure the accuracy of the experimental results; therefore, the current in the loop will change with the change of the color of the solution in the titration experiment, and the endpoint of the titration experiment can be judged by observing the real-time current.

[0042] In order to further illustrate the structure of the data processing module 2 so that it can meet the demand for displaying current data, the data processing module 2 includes a box 21 as an installation carrier, and an ammeter 22 for detecting the current passing through the photoresistor 14 is arranged in the box 21. A power supply 23 for forming a loop with the ammeter 22 and the photoresistor 14 is also arranged in the box 21. A switch 24 for controlling the on and off of the loop is arranged on the surface of the box 21. The change of current can be known by the indication of the ammeter 22, and of course it can also be displayed by other electronic display screens.

[0043] Since the samples to be tested in different titration experiments change color differently during the titration experiments, different bandpass filters 13 need to be replaced according to different experimental scenarios. In order to facilitate the replacement of the bandpass filter 13, a connecting tube 15 for inserting into the end of the protective hose 11 is provided at the bottom of the suction cup 12. The light signal processed by the bandpass filter 13 can be captured by the photoresistor 14 through the connecting tube 15. A protrusion 16 is provided at the end of the connecting tube 15, and a card slot 17 fixed with the protrusion 16 is provided at the end of the protective hose 11. Through the mutual cooperation of the protrusion 16 and the card slot 17, the suction cup and the bandpass filter 13 can be replaced.

[0044] When the device is stored, light or foreign matter may enter the photoelectric conversion module 1, thereby damaging the bandpass filter and the photoresistor. Therefore, a detachable opaque protective cover 18 is provided at the mouth of the suction cup 12, so that it can block light or prevent foreign matter from entering the photoelectric conversion module 1 when the device is stored, thereby protecting the bandpass filter and the photoresistor from damage, thereby extending the service life of the device.

[0045] This embodiment also provides a method for using the device for quickly titrating the end point of road dust content to quantitatively determine whether the titration experiment has reached the end point, such as Figure 3 As shown, the method comprises the following steps:

[0046] S1, determine the initial color of the solution to be tested in the titration experiment and the solution color at the end point of the titration experiment, and select the bandpass filter 13 corresponding to the initial color; according to the color change of the calcium content at the end point of the titration experiment in the test procedure for inorganic binder stabilized materials for highway engineering from red to blue, select the red bandpass filter 13 for matching;

[0047] S2, prepare a blue colorimetric solution with the same color as the titration endpoint of the solution to be tested according to the standard specification, adsorb the suction cup 12 on the bottom of the container containing the colorimetric solution, turn on the switch 24 to obtain the comparison current, specifically including the following steps:

[0048] S21. According to the standard specifications, prepare the relevant reagents for the preparation of the colorimetric solution with the same color as the endpoint solution of the titration experiment, including: distilled water, buffer solution and indicator; relevant reagents and a method for preparing the reagents:

[0049] Distilled water;

[0050] 20% sodium hydroxide solution: Dissolve 20 grams of sodium hydroxide in 80 milliliters of distilled water;

[0051] Calcium indicator: 0.2 g of calcium reagent sodium carboxylate and 20 g of potassium sulfate dried at 105°C are mixed and ground into powder and stored in a brown wide-mouth bottle;

[0052] S22, adding z milliliters of distilled water, a milliliters of buffer and b grams of indicator into the container to prepare a colorimetric solution;

[0053] in:

[0054] z=l1+l2+l3

[0055] In the above formula, l1 is the amount of the clear liquid of the sample to be tested after treatment in the titration experiment in the standard specification, l2 is the amount of distilled water added to dilute the upper clear liquid in the titration experiment in the standard specification, l3 is the amount of other reagents added in the titration experiment in the standard specification, a is the amount of buffer added in the titration experiment in the standard specification; b is the amount of indicator added in the standard specification; the specific name of the standard specification varies according to the different experimental fields and objects, such as "Test Procedures for Stabilized Materials of Inorganic Binders for Highway Engineering";

[0056] For example, in the EDTA titration experiment of calcium content in the test procedures for inorganic binder stabilized materials for highway engineering, z=180 ml is calculated, l1 is the amount of 25 ml of the clear solution of the sample to be tested after treatment in the standard specification; l2 is the amount of distilled water added to dilute the upper clear solution in the standard specification, 150 ml; l3 is the amount of triethanolamine solution added in the standard specification, 5 ml; a is the amount of 20% sodium hydroxide buffer added in the standard specification, 5 ml; b is the amount of calcium indicator added in the standard specification, 0.2 g

[0057] S23, adsorb the suction cup 12 on the bottom of the container containing the colorimetric solution, and turn on the switch 24 to obtain the comparison current.

[0058] S3, adsorb the suction cup 12 on the bottom of the container containing the supernatant of the solution to be tested, then continuously drip the titration solution into the supernatant of the solution to be tested, and observe the real-time current, which is displayed in real time by the ammeter 22;

[0059] S4, calculating the current difference percentage between the real-time current and the comparison current, and determining whether the current difference percentage is within the current difference threshold;

[0060] If not, return to step S3;

[0061] If yes, stop the titration and record the consumption of titration solution;

[0062] The current difference percentage is calculated as:

[0063]

[0064] In the above formula, ω represents the current difference percentage, I i It represents the real-time current during the i-th titration, and I1 is the comparison current.

[0065] S5. Turn off the endpoint determination device for the rapid titration detection of road dust content.

[0066] It should be noted that, in this article, the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or apparatus.

[0067] Although embodiments of the present invention have been shown and described, it will be appreciated by those skilled in the art that various changes, modifications, substitutions and variations may be made to the embodiments without departing from the principles and spirit of the present invention, and that the scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A device for determining the endpoint of rapid titration detection of road dust content, comprising a data processing module (2) for collecting and displaying electrical signals, characterized in that: It also includes a photoelectric conversion module (1) for collecting light signals in the solution and converting them into electrical signals; The photoelectric conversion module (1) comprises a light-proof protective hose (11); a suction cup (12) for adsorbing on the bottom of a reaction container is arranged at the end of the protective hose (11); a bandpass filter (13) for allowing only light signals of a specific wavelength band to pass is arranged in the suction cup (12); and a photoresistor (14) for converting light signals processed by the bandpass filter (13) into electric signals and transmitting the electric signals to the data processing module (2) is arranged in the protective hose (11).

2. The device for determining the endpoint of rapid titration detection of road dust content according to claim 1, characterized in that: The data processing module (2) comprises a box (21) as a mounting carrier, an ammeter (22) for detecting the magnitude of a current passing through a photoresistor (14) is arranged inside the box (21), a power supply (23) for forming a circuit with the ammeter (22) and the photoresistor (14) is also arranged inside the box (21), and a switch (24) for controlling the on / off of the circuit is arranged on the surface of the box (21).

3. The device for determining the endpoint of rapid titration detection of road dust content according to claim 1, characterized in that: A connecting tube (15) for inserting into the end of the protective hose (11) is arranged at the bottom of the suction cup (12); the optical signal processed by the bandpass filter (13) can be captured by the photoresistor (14) through the connecting tube (15); a protrusion (16) is arranged at the end of the connecting tube (15); and a slot (17) for cooperating and fixing with the protrusion (16) is arranged at the end of the protective hose (11).

4. The device for determining the endpoint of rapid titration detection of road dust content according to claim 1, characterized in that: The mouth of the suction cup (12) is provided with a detachable opaque protective cover (18).

5. The method for using the device for rapid titration detection endpoint determination of road dust content according to any one of claims 1 to 4, characterized in that: The method comprises the following steps: S1, determining the initial color of the solution to be tested in the titration experiment and the color of the solution at the end point of the titration experiment, and selecting a bandpass filter (13) corresponding to the initial color; S2. Prepare a colorimetric solution with the same color as the endpoint solution of the titration experiment according to standard specifications, and adsorb the suction cup (12) to the bottom of the container containing the colorimetric solution, turn on the switch (24), and obtain the comparison current; S3, adsorbing the suction cup (12) on the bottom of the container containing the supernatant of the solution to be tested, then continuously dripping the titration solution into the supernatant of the solution to be tested, and observing the real-time current; S4, calculating the current difference percentage between the real-time current and the comparison current, and determining whether the current difference percentage is within the current difference threshold; If not, return to step S3; If yes, stop the titration and record the consumption of titration solution; S5. Turn off the endpoint determination device for the rapid titration detection of road dust content.

6. The method of use according to claim 5, characterized in that: In step S2, the following steps are specifically included: S21. Prepare the relevant reagents for preparing the colorimetric solution according to the standard specifications, including: distilled water, buffer and indicator; S22, adding z milliliters of distilled water, a milliliters of buffer and b grams of indicator into the container to prepare a colorimetric solution; in: z＝l1+l2+l3 In the above formula, l1 is the amount of the clear solution of the sample to be tested after treatment in the titration experiment in the standard specification, l2 is the amount of distilled water added to dilute the supernatant in the titration experiment in the standard specification, l3 is the amount of other liquid reagents added in the titration experiment in the standard specification, a is the amount of buffer added in the titration experiment in the standard specification; b is the amount of indicator added in the standard specification; S23, adsorb the suction cup to the bottom of the container containing the colorimetric solution to obtain the comparison current.

7. The method of use according to claim 5, characterized in that: In step S4, the current difference percentage is calculated as: In the above formula, ω represents the current difference percentage, I i It represents the real-time current during the i-th titration, and I1 is the comparison current.

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