Solution ion detection model based on evaporation energy self-power supply and application and system thereof

Abstract

The invention discloses a solution ion detection model based on evaporation energy self-power supply as well as application and a system thereof. The model comprises the following steps: diluting a standard solution of ions according to a concentration gradient to a constant volume, obtaining a series of ion standard samples, obtaining an electric signal when the ion standard samples are evaporated, sequentially converting the electric signal into an analog signal and a digital signal, carrying out imaging processing on the digital signal, obtaining a voltage-time image of the ion standard samples, and calculating the voltage-time image of the ion standard samples. And classifying and summarizing the images according to ion types and concentrations. The model can be used for on-line detection of ions in a solution, an on-line detection system provided based on the model can convert low-quality and easily-dissipated evaporation energy of solution evaporation into electric energy, and on-line detection of the solution can be achieved without sampling and sample pretreatment; the system is simple in structure and low in cost, and can meet the requirements of different detection ions, different detection limits and different precisions in the online detection process.

Description

Technical Field

[0001] The invention relates to a solution ion detection model, in particular to a solution ion detection model based on evaporation energy self-power supply and its application and system, belonging to the technical field of ion sensing. Background Art

[0002] With the rapid development of smart factories, higher requirements are placed on real-time and accurate sensing of various parameters in industrial production, and the real-time sensing of ions in solution is very important for the construction of smart factories. Existing methods for detecting ions in solution are basically non-in-situ and cannot achieve real-time detection. At the same time, common atomic absorption spectroscopy, liquid chromatography, spectrophotometer and other methods require expensive equipment and extremely professional operators, and can only take samples for detection at regular intervals, and cannot perform real-time detection and remote monitoring of the solution components in the production process. Summary of the invention

[0003] In view of the problems existing in the prior art, the first purpose of the present invention is to provide a solution ion detection model based on evaporation energy self-powered. The model converts the dissolution evaporation energy into electrical energy through a self-powered sensor. When solutions containing ions of different concentrations evaporate along the device, the surface potential changes differently, and different electrical signals are generated at both ends of the sensor. The obtained electrical signals are then converted and de-noised, thereby realizing online detection of the types and concentrations of ions in the solution.

[0004] The second object of the present invention is to provide an application of a solution ion detection model based on evaporation energy self-power supply for online detection of ions in solution.

[0005] The third object of the present invention is to provide a solution ion detection system based on evaporation energy self-powered. The detection system can convert the low-quality and easily dissipated evaporation energy of the solution into electrical energy, and has the potential to be a new energy conversion device. The system does not require an operator, can realize a self-powered ion sensing process, and can further realize real-time monitoring of the solution in the production process without the need for sampling and sample pretreatment processes; the system has a simple structure and low cost, and can meet the requirements of different detection ions, different detection limits and different precisions in the online detection process.

[0006] In order to achieve the above technical objectives, the present invention provides a solution ion detection model based on evaporation energy self-powered, comprising:

[0007] Step S1, diluting the standard solution of each ion to be detected in the test solution according to the concentration gradient to obtain a series of ion standards;

[0008] Step S2, obtaining the electrical signal of the ion standard sample during evaporation through the self-powered sensor, and converting it into a continuous analog signal;

[0009] Step S3, the analog signal is subjected to digital conversion and noise reduction processing to obtain a corresponding digital signal, and then the digital signal is processed into an image to obtain a voltage-time image of the ion standard;

[0010] Step S4, classify and summarize the voltage-time images of all ion standards according to ion types and concentrations, and obtain;

[0011] The digital conversion process is performed by a double integral conversion method; the noise reduction process is performed by a recursive filtering method.

[0012] As a preferred solution, the self-powered sensor is composed of a substrate layer, a porous structure layer and a surface functionalization layer. The solution evaporates upward through capillary tension, the evaporation energy is converted into electrical energy, and an electrical signal is obtained.

[0013] As a preferred solution, the base layer is made of an insulating material with good mechanical properties and easy processing, preferably at least one of soda-lime glass, borosilicate glass, ceramics and high molecular polymers.

[0014] In the present invention, there should be relatively small void channels in the porous structure layer to ensure that the solution can evaporate upward spontaneously by capillary force, thereby being able to continuously convert low-quality, easily dissipated evaporation energy into electrical energy.

[0015] As a preferred solution, the material of the porous structure layer is at least one of oxide materials, sulfide materials, carbon materials, organic biological materials and organic polymer materials.

[0016] As a preferred solution, the surface functionalization layer is highly selective to one or more specific ions and can be constructed on a porous structure layer, and its material is at least one of a chelating agent, an antibiotic, an organic salt and a coupling agent.

[0017] As a preferred solution, the electrical signal generated when the ion standard sample evaporates includes current, voltage and time.

[0018] As a preferred solution, the process of the double integral conversion method is: converting the input voltage in the analog signal into a pulse width or a pulse frequency, and then determining its digital value by a timer. The approximate formula of the conversion process is:

[0019] Formula 1: V in / V ref =m / 2 N ;

[0020] In formula 1, V in is the input analog signal, the dimension is V; V refis the reference voltage, dimension is V; m is the output digital signal, dimensionless, 2 N is the resolution.

[0021] As a preferred solution, the recursive filtering method is Kalman filtering, and its process is: under the premise of linearity and conformity to Gaussian distribution, the estimation of the state variable is updated according to the prior results and the observed value at the current moment, and the estimated value at the current moment is obtained.

[0022] The present invention also provides an application of a solution ion detection model based on evaporation energy self-power supply, which is used for online detection of cations in a solution.

[0023] The present invention also provides a solution ion detection system based on evaporation energy self-powered, which is used to implement any of the models described above, including a self-powered sensing module, an electrical signal acquisition module, an A / D conversion module, a filtering module, a remote monitoring module and a result processing module.

[0024] As a preferred solution, the self-powered sensing module includes a self-powered sensor that converts the evaporation energy of the solution into electrical energy to power other modules of the system.

[0025] As a preferred solution, the self-powered sensing module includes a plurality of self-powered sensors, and the voltage and current can be increased by circuit design methods such as series connection and parallel connection to meet the demand for power supply for the entire system. When one end of the self-powered sensor is immersed in the solution to be detected, the solution to be detected can evaporate upward spontaneously along the detection component, and the ions in the solution to be detected will change the potential on the surface of the detection component. Due to the different surface potentials of the wetted and dried parts, the detection component will produce a potential difference. When the circuit is closed, electrical energy will be generated, which can be used as a power source to provide electrical energy for other modules of the system. At the same time, the surface of the self-powered sensor in the module is sensitive to ions. When solutions containing ions of different concentrations evaporate along the device, the changes in the surface potential are different, and different electrical signals will be generated at both ends of the sensor.

[0026] As a preferred solution, the electrical signal acquisition module collects the electrical signal obtained by the power supply sensor module and converts it into an analog signal that is continuous in both time and amplitude.

[0027] As a preferred solution, the A / D conversion module converts the obtained analog signal into a digital signal with discrete time and amplitude.

[0028] As a preferred solution, the filtering module removes noise in the digital signal.

[0029] As a preferred solution, the remote monitoring module receives the digital signal after noise reduction and transmits it through at least one of a threshold port, a display port and a wireless transmission port.

[0030] As a preferred solution, the result processing module receives the signal transmitted by the remote monitoring module, calculates the ion concentration, performs visualization engineering, and outputs an image.

[0031] As a preferred solution, the remote monitoring module has a built-in single-chip microcomputer for receiving digital signals.

[0032] As a preferred solution, the threshold port is connected to a buzzer, which sounds an alarm when the received digital signal exceeds the threshold.

[0033] As a preferred solution, the display port is connected to a display to display digital signals in real time.

[0034] As a preferred solution, the wireless transmission port is connected to a Bluetooth and / or WiFi transmitter to wirelessly transmit the digital signal to the result processing module.

[0035] As a preferred solution, the A / D conversion module is a dual-integral A / D converter.

[0036] As a preferred solution, the filtering module is a Kalman filter. Kalman filtering has a small amount of calculation, is convenient for real-time processing, and has super high system accuracy and robustness. However, the prerequisite of Kalman filtering is that the system must be linear, and the noise distribution needs to be Gaussian distribution. When the system is nonlinear, Taylor expansion is required, and its computational complexity grows exponentially, and the deviation is large. In addition, even if the system is linear, when the noise is non-Gaussian, the mean square error (MSE) cannot be obtained, and only the linear minimum mean square error (LMMSE) can be obtained. In this case, the obtained LMMSE differs greatly from the MMSE (minimum mean square error), and it is difficult to achieve the stability of signal processing; and the signal acquisition method provided in the present invention is to generate a potential difference through the deposition effect of ions in the wet and dry places during the evaporation of the solution, and then generate current and electrical signals. The signal meets the requirements of composite linearity after double integral conversion, and its noise also meets the Gaussian distribution, so that the Kalman filtering method can be directly adopted, while reducing the amount of calculation, the signal quality is also greatly improved.

[0037] Compared with the prior art, the beneficial technical effects of the technical solution of the present invention are:

[0038] 1) The detection model provided by the present invention converts dissolution evaporation energy into electrical energy through a self-powered sensor. When ion solutions containing different concentrations evaporate along the device, the changes in the surface potential are different, and different electrical signals are generated at both ends of the sensor. The obtained electrical signals are then converted and denoised, thereby realizing online detection of the types and concentrations of ions in the solution.

[0039] 2) In the technical solution provided by the present invention, the analog signal is converted into a digital signal by a double integral conversion method. On the one hand, the double integral conversion can automatically offset the drift and additional noise of the input signal, thereby greatly improving its anti-interference ability and conversion accuracy. On the other hand, the time required in the double integral conversion process coincides with the stabilization time required in the solution evaporation process, which effectively offsets the defect of the low measurement rate of the double integral conversion. In addition, since the solution electrical signal collected by the present invention is generated based on the evaporation of the solution, it belongs to a linear system, and its noise belongs to a Gaussian distribution. Therefore, the use of Kalman filtering has super high system accuracy and efficiency.

[0040] 3) The detection system provided by the present invention can convert the low-quality and easily dissipated evaporation energy of the solution into electrical energy, and has the potential to be used as a new energy conversion device. The system does not require an operator and can realize a self-powered ion sensing process, thereby realizing real-time monitoring of the solution in the production process without the need for sampling and sample pretreatment processes. The system has a simple structure and low cost, and can meet the requirements of different detection ions, different detection limits and different precisions in the online detection process. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0042] Figure 1 This is a module structure diagram of a self-powered ion sensing system based on solution evaporation provided by the present invention;

[0043] Figure 2 It is a schematic diagram of the sensing process of a self-powered ion sensing system based on solution evaporation provided by the present invention;

[0044] Figure 3 It is a circuit connection diagram of the detection devices in the self-powered sensor module of the present invention (a) in series and (b) in parallel;

[0045] Figure 4 It is a working mode diagram of the detection device in the self-powered sensor module of the present invention;

[0046] Figure 5 is a voltage-time diagram of repeated detection of 1M NaCl in Example 1 of the present invention;

[0047] Figure 6 The 0.01M Pb was repeatedly detected in Example 1 of the present invention. 2+ Voltage-time diagram of . DETAILED DESCRIPTION

[0048] To make the purpose, technical solution and advantages of the present invention clearer, the technical solution of the present invention will be described in detail below. Obviously, the described embodiments are only part of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other implementation methods obtained by ordinary technicians in this field without creative work belong to the scope of protection of the present invention.

[0049] like Figure 1 As shown, a self-powered ion sensing system based on solution evaporation includes: a self-powered sensing module, an electrical signal acquisition module, an A / D conversion module, a filtering module, a remote monitoring module, and a result processing module;

[0050] The self-powered sensor module is used to detect the ions in the solution to be detected 9 in real time, and convert the evaporation energy of the solution into electrical energy, and is an electrical signal acquisition module, an A / D conversion module, a filtering module, and a remote monitoring module.

[0051] Specifically, the self-powered sensing module includes a plurality of detection components 10, wherein the connection between the detection components 10 is at least one of series connection and parallel connection. When one end of the detection component 10 is immersed in the solution 9 to be detected, the solution 9 to be detected can evaporate spontaneously along the detection component 10, and the ions in the solution 9 to be detected will change the surface potential of the detection component 10. Since the surface potentials of the wetted and dried parts are different, the detection component 9 will generate a potential difference, and voltage and current will be generated when the circuit is closed. When solutions with different concentrations of ions evaporate along the device, the changes in the surface potential are different, and different electrical signals will be generated at both ends of the detection component 9. The electrical signal acquisition module collects these signals and transmits the electrical signals to a distant computer in real time through the remote monitoring module.

[0052] More specifically, the detection component 9 includes a substrate 12, a porous structure layer 13, and a surface functionalization layer 14. During specific implementation, various optimization layers and packaging structures may be added.

[0053] More specifically, the base layer 12 is made of insulating material with good mechanical properties and easy processing, and can be one or more of soda-lime glass, borosilicate glass, ceramics, and high molecular polymers.

[0054] More specifically, the size of the pore channels in the porous structure layer 13 can ensure that the solution to be detected 9 can evaporate upward spontaneously by capillary force. The use of a porous structure can make the solution to be detected 9 evaporate upward spontaneously based on the capillary force of the detection component 10, so that the low-quality, easily dissipated evaporation energy can be continuously converted into electrical energy. At the same time, the surface of the detection device is sensitive to ions, and the output electrical signal will change with the ion composition and concentration in the evaporating solution. The circuit design of multiple detection components 10 in series and / or parallel allows the voltage and current to be amplified to meet the needs of the electrical signal acquisition module and the remote monitoring module for the computer.

[0055] More specifically, the porous structure layer 13 is made of oxide materials (CuO, TiO 2 、Al 2 O 3 , Fe 2 O 3 , Mn 3 O 4 、ZnO、SnO 2 , Fe 3 O 4 、SiO 2 etc.), sulfide materials (MoS 2 , WS 2 etc.), carbon materials (carbon black, carbon nanotubes, graphene, etc.), organic biomaterials, organic polymer materials, etc.

[0056] More specifically, the surface functionalized layer 14 is a material that can select one or more specific ions and can be connected to the porous structure layer 13. In specific implementation, the surface functionalization of the material can be improved to meet the selectivity requirements of the actual detection component 9 for ions.

[0057] The electrical signal acquisition module is used to continuously acquire different electrical signals generated by the detection component 9 in the self-powered sensor module.

[0058] The A / D conversion module adopts a dual-integral A / D converter to convert the analog signal collected in the electrical signal collection module into a digital signal.

[0059] The filtering module uses a Kalman filter to remove noise in the digital signal, making the entire output signal smoother.

[0060] The remote monitoring module can generate an alarm when the concentration of the solution is too high or too low by connecting a buzzer to the single-chip microcomputer; connect an OLED display screen to display the generated electrical signal in real time; and connect a Bluetooth wireless transmission serial port to enable the electrical signal to be wirelessly transmitted to the PC serial port in real time.

[0061] The result processing module inputs the obtained digital electrical signal into the corresponding ion concentration model, calculates the corresponding ion concentration, and performs a visual graphical output display;

[0062] The ion concentration model in the result processing module is obtained by the following method: selecting a detection device with a suitable sensitive layer according to the type of ion to be monitored, selecting different standard concentration solutions corresponding to the ion to be measured, and measuring the corresponding electrical signals at each standard concentration; drawing a standard function model relationship based on different standard concentrations and corresponding electrical signals to obtain the ion concentration model corresponding to the ion, and storing it in a computer program for subsequent call-up, so as to realize monitoring and adjustment of the production process.

[0063] In specific implementation, when a part of the entire detection component 10 is placed in the solution 9 to be detected, different electrical signals are generated as solutions of different concentrations evaporate upward from the detection component 10. The electrical signals are transmitted to the single-chip microcomputer through the wire 11 for electrical signal collection and remote wireless data transmission to the computer end. The electrical signals obtained by the computer end are input into the corresponding ion concentration model, the corresponding ion concentration is calculated, and a visual graphical output is displayed to further monitor and guide the production process.

[0064] The detection component 10 is described in detail by taking the porous CuO film as the porous structure layer 13 as an example:

[0065] The preparation of the detection assembly 10 includes the following steps:

[0066] 1. Porous CuO film as porous structure layer 13: A porous CuO film was prepared on a substrate 12 (glass) by drop casting and thermal oxidation;

[0067] 2. Preparation of surface functional layer: T-DETA was used to functionalize the porous CuO membrane by immersion method.

[0068] Example 1

[0069] Self-powered detection of solution salinity:

[0070] The detection component 10 is immersed in salt water. Since the CuO film is a porous structure, the solution can evaporate upward through capillary force. When NaCl contacts CuO, the surface potential of CuO changes. Therefore, a potential difference is generated between the part of the CuO film where the solution evaporates and the part of the CuO film where the solution does not evaporate. When an external circuit is connected to the wetted and dry parts, electrons will flow through the external circuit, generating a voltage, such as Figure 4 shown.

[0071] When one end of the detection device 10 is immersed in the test solution 9 containing NaCl, the electrical signal acquisition module 2 continuously collects the generated electrical signal, and converts the analog signal into a digital signal through the A / D conversion module 3 and the filtering module 4, and wirelessly transmits the data to the result processing module 6 through the remote monitoring module 5, and substitutes the obtained data into the existing ion concentration model to obtain the concentration of NaCl in the test solution.

[0072] It should be noted that the electrical signal obtained in this embodiment is a linear system, and the noise after double integral conversion also conforms to Gaussian distribution, and Kalman filtering is used for noise reduction processing.

[0073] One end of the detection device produced in different batches was immersed in the prepared 1MNaCl solution. The trend and value of the electrical signal generated by four consecutive tests fluctuated within a certain range, indicating that this detection device can be widely used for NaCl detection. When one end of the detection device was immersed in the test solution, the electrical signal could be continuously and stably generated after 90s. The electrical signal generated by 1MNaCl was 313mV, with a relative error of ±0.90%. Figure 5 shown.

[0074] Example 2

[0075] Pb 2+ Self-powered sensing:

[0076] T-DETA can be used with Cu 2+ and Pb 2+ Ions form chelate complexes, when containing Pb 2+ When the solution evaporates along the functionalized porous CuO film, Pb 2+ It is chemically adsorbed by complexing with T-DETA, changing the surface potential of the porous CuO film and generating an electrical signal to the outside.

[0077] It should be noted that the electrical signal obtained in this embodiment is a linear system, and the noise after double integral conversion also conforms to Gaussian distribution, and Kalman filtering is used for noise reduction processing.

[0078] Immerse one end of the detection devices produced in different batches into the configured 0.01M Pb 2+ The trend and value of the electrical signal generated by five consecutive tests in the solution fluctuate within a certain range, indicating that this detection device can be widely used in Pb 2+ When one end of the detection device is immersed in the solution to be tested, the electrical signal can be continuously and stably generated after 30 seconds. 2+ The generated electrical signal is 110mV, with a relative error of ±3.26%. Figure 6 shown.

[0079] It can be seen from Examples 1 and 2 that when the detection component 9 containing ions of different types and concentrations evaporates, a stable electrical signal can be continuously generated in a relatively short period of time. The type and concentration of ions contained in the water can be well judged through the detection results, confirming the feasibility and practicality of the self-powered ion sensing system based on solution evaporation.

[0080] It can be understood that the same or similar parts of the above embodiments can be referenced to each other, and the contents not described in detail in some embodiments can refer to the same or similar contents in other embodiments.

[0081] Although the embodiments of the present invention have been shown and described above, it is to be understood that the above embodiments are exemplary and are not to be construed as limitations of the present invention. A person skilled in the art may change, modify, replace and vary the above embodiments within the scope of the present invention.

Claims

1. A solution ion detection model based on evaporation energy self-powered, characterized in that: include: Step S1, diluting the standard solution of each ion to be detected in the test solution according to the concentration gradient to obtain a series of ion standard samples; Step S2, obtaining the electrical signal of the ion standard sample during evaporation through the self-powered sensor, and converting it into a continuous analog signal; Step S3, the analog signal is subjected to digital conversion and noise reduction processing to obtain a corresponding digital signal, and then the digital signal is processed into an image to obtain a voltage-time image of the ion standard; Step S4, classify and summarize the voltage-time images of all ion standards according to ion types and concentrations; the digital conversion process is performed by double integral conversion; the noise reduction process is performed by recursive filtering.

2. A solution ion detection model based on evaporation energy self-power supply according to claim 1, characterized in that: The self-powered sensor consists of a substrate layer, a porous structure layer and a surface functional layer. The solution evaporates upward through capillary tension, converts evaporation energy into electrical energy, and obtains electrical signals. The electrical signals when the ion standard evaporates include current, voltage and time.

3. A solution ion detection model based on evaporation energy self-power supply according to claim 1, characterized in that: The process of the double integral conversion method is: converting the input voltage in the analog signal into a pulse width or a pulse frequency, and then determining its digital value by a timer. The approximate formula of the conversion process is: Formula 1: V in / V ref =m / 2 N ; In formula 1, V in is the input analog signal, the dimension is V; V ref is the reference voltage, dimension is V; m is the output digital signal, dimensionless, 2 N is the resolution.

4. A solution ion detection model based on evaporation energy self-power supply according to claim 1, characterized in that: The recursive filtering method is Kalman filtering, and its process is: under the premise of linearity and conformity to Gaussian distribution, the estimation of state variables is updated according to the priori results and the observed values ​​at the current moment, and the estimated value at the current moment is obtained.

5. The application of a solution ion detection model based on evaporation energy self-power supply according to any one of claims 1 to 4, characterized in that: Used for online detection of ions in solution.

6. A solution ion detection system based on evaporation energy self-powered, characterized in that: The model used to implement any one of claims 1 to 4 comprises a self-powered sensing module, an electrical signal acquisition module, an A / D conversion module, a filtering module, a remote monitoring module and a result processing module.

7. The solution ion detection system based on evaporation energy self-power supply according to claim 6, characterized in that: The self-powered sensing module includes a self-powered sensor, which converts the evaporation energy of the solution into electrical energy to power other modules of the system; the electrical signal acquisition module collects the electrical signal obtained by the self-powered sensing module and converts it into an analog signal with continuous time and amplitude; The A / D conversion module converts the obtained analog signal into a digital signal which is discrete in both time and amplitude; The filtering module removes noise from the digital signal; the remote monitoring module receives the digital signal after noise reduction and transmits it through at least one of a threshold port, a display port and a wireless transmission port; The result processing module receives the signal transmitted by the remote monitoring module, calculates the ion concentration, performs visualization engineering, and outputs an image.

8. The solution ion detection system based on evaporation energy self-power supply according to claim 7, characterized in that: The remote monitoring module has a built-in single-chip microcomputer for receiving digital signals; the threshold port is connected to a buzzer, which sounds an alarm when the received digital signal exceeds the threshold; the display port is connected to a display to display the digital signal in real time; the wireless transmission port is connected to a Bluetooth and / or WiFi transmitter to wirelessly transmit the digital signal to the result processing module.

9. The solution ion detection system based on evaporation energy self-power supply according to claim 6, characterized in that: The A / D conversion module is a dual-integral A / D converter; The filtering module is a Kalman filter.

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