Transformer oil acetylene detection method and system based on click chemistry

Abstract

The application provides a transformer oil acetylene free degassing detection method and system based on click chemistry, relates to the technical field of gas detection and analysis, and utilizes a first product generated through a first click chemistry reaction and a second product generated through a second click chemistry reaction as catalysts to trigger subsequent same cascade chemical amplification reactions, so that a single product molecule can catalyze the hydrolysis of a large amount of acid-sensitive substrates, a significant and measurable change in the conductivity of a mixed solution is realized, precise detection of extremely low concentration acetylene is realized, meanwhile, a second click chemistry reaction of a synchronous internal standard reagent and a trigger agent exists independently of the process of acetylene concentration detection, calculation of acetylene detection is performed, the final output is not a single first electric signal value, but a ratio of the first electric signal value and a second electric signal value, a signal ratio is obtained, interference factors are offset, online self-correction of acetylene detection is realized, and the high consistency and accuracy of detection results under different times and different batches of reagents are ensured.

Description

Technical Field

[0001] This invention relates to the field of gas detection and analysis technology, specifically to a method and system for detecting acetylene in transformer oil without degassing, based on click chemistry. Background Technology

[0002] Transformers are core equipment in power systems, and early warning of internal faults is crucial. Acetylene gas dissolved in transformer oil is a key characteristic gas for diagnosing serious faults such as arc discharge. Currently, online monitoring of acetylene mainly relies on technologies such as gas chromatography and photoacoustic spectroscopy. These technologies all require first removing the dissolved gas from the oil and then analyzing it. This degassing-then-detection approach necessitates monitoring devices containing complex degassing modules (such as vacuum pumps and permeation membranes), resulting in large, complex systems with high maintenance costs. Furthermore, the degassing process itself introduces delays, affecting real-time performance.

[0003] To simplify systems and achieve rapid in-situ detection, degassing-free detection methods have emerged in existing technologies, such as degassing-free optical detection, chemical detection, and material detection. For example, CN116199898A discloses a metal-organic framework material for rapid detection of acetylene and its preparation method. In its application to the detection of dissolved acetylene in transformer oil, acetylene is detected by the color change caused by the interaction of acetylene with the material. However, the detection accuracy is insufficient, and the color quantification is easily interfered with. In chemical detection methods, the cycloaddition reaction of acetylene with sodium azide consumes electrolytes, and the acetylene concentration is estimated by measuring the change in solution conductivity. However, in practical applications, since the acetylene content in transformer oil is extremely low, usually at the ppm level, the conductivity change caused by this trace reaction is extremely weak and is completely overwhelmed by the fluctuations in the conductivity of the ionic liquid itself with temperature and humidity, as well as the background noise of the detection instrument. The signal-to-noise ratio is too low, making it impossible to achieve stable and reliable quantitative measurement. Furthermore, any detection method that relies on a single physical quantity (such as absolute conductivity measurement) is difficult to overcome systematic errors caused by fluctuations in reaction conditions and catalytic activity decay, and the stability and accuracy of long-term monitoring cannot be guaranteed.

[0004] In summary, the existing technology has the following technical problems when used:

[0005] Problem 1: When using chemical methods to detect acetylene, the existing degassing-free click chemical conductivity method fails due to the extremely weak signal change, resulting in low sensitivity and poor stability for acetylene detection, and failing to provide stable and reliable quantitative measurement.

[0006] Question 2: When using chemical methods to detect acetylene, measurement errors caused by factors such as environmental fluctuations, reagent consumption, and device drift during long-term operation lead to deviations in the acetylene concentration detection results, resulting in low precision and accuracy, and failing to meet the measurement accuracy requirements. Summary of the Invention

[0007] To achieve the above objectives, the present invention provides the following technical solution: a click chemistry-based method for detecting acetylene in transformer oil without degassing, the method comprising:

[0008] The transformer oil sample to be tested is mixed with an ionic liquid in a mixing reaction chamber, and the acetylene-containing ionic liquid phase is separated.

[0009] Simultaneously add the measuring reagent and the internal standard reagent to the ionic liquid phase. Based on the first click chemical reaction of the measuring reagent in the ionic liquid phase, a first product is generated. The trigger in the internal standard reagent reacts with the second azide component to generate a second product.

[0010] After triggering the same cascade chemical amplification reaction on the first and second products respectively, hydrogen ions are released. The changes in conductivity after the reaction are measured to obtain the first and second conductivity changes.

[0011] A first electrical signal value is calculated based on the first change in conductivity, and a second electrical signal value is calculated based on the second change in conductivity. The ratio of the first electrical signal value to the second electrical signal value is then calculated to obtain the signal ratio.

[0012] Based on a pre-established standard curve showing the relationship between signal ratio and acetylene concentration, the acetylene concentration in the transformer oil sample to be tested is calculated based on the signal ratio.

[0013] Furthermore, the step of obtaining the transformer oil sample to be tested and mixing it with the ionic liquid in a mixing reaction chamber to separate the acetylene-containing ionic liquid phase includes:

[0014] A first volume of the transformer oil sample to be tested is measured and injected into a mixing reaction chamber containing a second volume of ionic liquid.

[0015] The mixing reaction chamber is heated and maintained at a preset first temperature, while stirring is performed for a first preset time, so that the acetylene in the transformer oil sample to be tested is balanced between the oil phase and the ionic liquid phase.

[0016] Stop stirring and let stand for the second preset time. After the ionic liquid phase and oil phase have completely separated, remove all of the ionic liquid phase.

[0017] Furthermore, the simultaneous addition of the measuring reagent and the internal standard reagent to the ionic liquid phase includes:

[0018] Add a third solution containing a copper catalyst to all the extracted ionic liquid phases, and simultaneously add a measuring reagent containing a known concentration of the first azide component and an internal standard reagent containing a known concentration of the second azide component and a trigger.

[0019] The temperature of the ionic liquid phase is controlled at a preset second temperature to carry out the first click chemical reaction and the second click chemical reaction, and the reaction time is a third preset time.

[0020] The first click chemical reaction is carried out in an ionic liquid phase in the presence of a copper catalyst, consuming a first azide component in an amount equal to that of acetylene to generate a first product. The second click chemical reaction is carried out simultaneously in the same reaction environment in the presence of a trigger, consuming a predetermined amount of a second azide component to generate a second product.

[0021] Furthermore, obtaining the first conductivity change value and the second conductivity change value by measuring the conductivity change after the reaction includes:

[0022] Before the start of the cascade chemical amplification reaction, the initial baseline conductivity value in the ionic liquid phase is obtained. The mixture containing the first and second products is transferred to the signal amplification reaction cell, which is pre-filled with an acid-sensitive substrate.

[0023] Using the first and second products as catalysts, acid-sensitive substrates were hydrolyzed to continuously release hydrogen ions. The total steady-state conductivity of the current mixture after the cascade chemical amplification reaction stabilized was measured. A blank correction experiment was set up to obtain the second steady-state conductivity measurement contributed only by the second product.

[0024] The total change in steady-state conductivity before and after the reaction is measured, and the first and second conductivity changes are calculated using the difference method.

[0025] Furthermore, the step of calculating the first electrical signal value based on the acquired first conductivity change value and calculating the second electrical signal value based on the acquired second conductivity change value includes:

[0026] The first electrical signal value is obtained by linearly transforming the first conductivity change value;

[0027] After obtaining the first electrical signal value, an alkaline neutralizing solution is added to the mixture to terminate the cascade chemical amplification reaction and reset the system. Under blank conditions without acetylene, the second steady-state conductivity measurement value generated solely by the second product is obtained. The second conductivity change value is obtained by subtracting the initial baseline conductivity measurement value from the second steady-state conductivity measurement value. The second electrical signal value is obtained by linearly transforming the obtained second conductivity change value.

[0028] Calculate the quotient of the first voltage signal and the second voltage signal to obtain the signal ratio.

[0029] Furthermore, the calculation of the acetylene concentration value in the transformer oil sample based on the signal ratio includes:

[0030] N standard oil samples with known acetylene concentrations were obtained. The signal ratio of each standard oil sample was calculated. The amount of known acetylene in each standard oil sample was used as the abscissa, and the measured signal ratio was used as the ordinate. After linear regression fitting, the obtained linear equation was used as the standard curve of the relationship between the signal ratio and the acetylene concentration.

[0031] The signal ratio measured from the transformer oil sample to be tested is substituted into the linear equation of the labeled curve to calculate the amount of acetylene extracted in the ionic liquid phase.

[0032] Based on the first volume of the transformer oil sample to be tested, the amount of acetylene is converted into the acetylene concentration value in the transformer oil sample to be tested.

[0033] Furthermore, the first azide component is a tetrazolium derivative capable of generating azide groups in situ through tautomerism in an ionic liquid phase in the presence of a copper catalyst, and undergoing a first click chemical reaction with acetylene.

[0034] Furthermore, the second azide component is an azide compound with a cleavable fluorescent reporter group attached; the second click chemistry reaction is a strain-promoted azide-alkyne cycloaddition reaction, and the trigger is a ring-strained alkyne. After the reaction, the cleavable fluorescent reporter group is quantitatively released.

[0035] Furthermore, the calculation of the second electrical signal value also includes:

[0036] After the second product is generated, the ionic liquid phase is subjected to fluorescence detection.

[0037] The fluorescence intensity of the quantitatively released cleavable fluorescent reporter group is measured and used as the second electrical signal value.

[0038] Furthermore, a click chemistry-based acetylene detection system for transformer oil without degassing is provided, the system comprising:

[0039] The sample flow path and reaction control module is used to obtain the transformer oil sample to be tested and the ionic liquid are mixed in the mixing reaction chamber, and the acetylene-containing ionic liquid phase is separated.

[0040] The reagent dosing and driving module is used to simultaneously add measuring reagents and internal standard reagents to the ionic liquid phase to carry out click chemistry reactions and generate the first product and the second product.

[0041] The signal amplification and conversion module is used to trigger the same cascade chemical amplification reaction of the first product and the second product to release hydrogen ions. The change in conductivity after the reaction is measured to obtain the change in first conductivity and the change in second conductivity.

[0042] The signal acquisition and data processing module is used to calculate a first electrical signal value based on the acquired first conductivity change value, calculate a second electrical signal value based on the acquired second conductivity change value, calculate the ratio of the first electrical signal value to the second electrical signal value to obtain the signal ratio, and calculate the acetylene concentration value in the transformer oil sample to be tested through a standard curve based on the signal ratio.

[0043] The system control and human-machine interaction module is used for parameter input, control and display of the sample flow path and reaction control module, reagent dosing and driving module, signal amplification and conversion module and signal acquisition and data processing module.

[0044] This invention provides a method and system for detecting acetylene in transformer oil without degassing, based on click chemistry. It has the following beneficial effects:

[0045] 1. This invention utilizes the first product generated by the first click chemical reaction and the second product generated by the second click chemical reaction as catalysts to trigger subsequent identical cascade chemical amplification reactions. This allows a single product molecule to catalyze the hydrolysis of a large amount of acid-sensitive substrate, continuously releasing hydrogen ions. This leads to an exponential increase in the hydrogen ion concentration in the solution, ultimately manifesting as a significant and measurable change in the conductivity of the mixture. This transforms the initial weak chemical event into a macroscopic and easily measurable physical signal, providing a first conductivity change value that is proportional to the acetylene content. Thus, even for extremely low concentrations of acetylene, a clear first electrical signal value far exceeding the detection threshold is generated, overcoming the defect of being undetectable due to weak signals. This achieves highly sensitive, degassing-free direct detection of acetylene in transformer oil at ppm and even ppb levels.

[0046] 2. This invention employs a dual-channel internal standard ratio detection logic, enhancing anti-interference capabilities and long-term stability. It utilizes a second-click chemical reaction occurring synchronously with the internal standard reagent and trigger to generate a fixed amount of a second product. This reaction exists independently of the acetylene concentration detection process, but undergoes the same subsequent cascaded chemical amplification reaction and signal detection process as the measurement channel, producing a second conductivity change value and a corresponding second electrical signal value. The final output is not a single first electrical signal value, but rather the ratio of the first to the second electrical signal value. Any common interference factors affecting both reaction channels simultaneously, such as reaction rate fluctuations caused by changes in ambient temperature, batch-to-batch differences in copper catalyst activity, ionic liquid background conductivity drift, and detector gain changes, will proportionally affect the first and second electrical signal values. During the ratio calculation, common interferences are synchronously canceled out. The final signal ratio used for concentration inversion is only related to the specific reaction amount of acetylene and is independent of common noise. Through a built-in real-time reference system, online self-calibration is achieved, ensuring high consistency and accuracy of detection results across different times and batches of reagents. Attached Figure Description

[0047] Figure 1 This is a flowchart illustrating the steps of the click chemistry-based method for detecting acetylene in transformer oil without degassing, as described in this invention.

[0048] Figure 2 This is a data flow diagram of the click chemistry-based acetylene detection method for transformer oil without degassing, as described in this invention.

[0049] Figure 3 This is a diagram illustrating the architecture of the transformer oil acetylene detection system based on click chemistry, as described in this invention. Detailed Implementation

[0050] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0051] like Figures 1 to 2 As shown, a click chemistry-based method for detecting acetylene in transformer oil without degassing is described, the method comprising:

[0052] Step S100: The transformer oil sample to be tested is mixed with the ionic liquid in the mixing reaction chamber, and the acetylene-containing ionic liquid phase is separated.

[0053] First, a first volume of the transformer oil sample to be tested is measured and injected into a mixing reaction chamber containing a second volume of ionic liquid;

[0054] Then, the mixing reaction chamber is heated and maintained at a preset first temperature, while stirring is performed for a first preset time, so that the distribution of acetylene in the transformer oil sample to be tested is balanced between the oil phase and the ionic liquid phase.

[0055] Finally, stop stirring and let it stand for the second preset time. After the ionic liquid phase and the oil phase have completely separated, take out all the ionic liquid phase. Through separation, the ionic liquid phase that has completed acetylene extraction is physically separated from a large amount of transformer oil phase, thereby obtaining a pure test solution rich in acetylene and completely eliminating the interference of oil phase on subsequent precision chemical reactions. After separation, in the mixing reaction chamber, it can be clearly observed that the upper layer is a clear transformer oil phase and the lower layer is a slightly more viscous ionic liquid phase. There is a flat horizontal interface between the two phases. Through the outlet valve located at the bottom of the mixing reaction chamber, gravity or a micro pump is used to slowly and completely transfer all the lower ionic liquid phase to the subsequent click chemical reaction chamber. Precise control is required to avoid the aspiration of the upper oil phase. The click chemical reaction chamber is used to carry out the click chemical reaction in step S200.

[0056] The transformer oil sample to be tested is an untreated insulating oil obtained from the circulating oil circuit of a running power transformer, oil tank, or online monitoring system through a sampling valve. Its main components are mineral oil or synthetic ester base oil, and it contains trace amounts of characteristic gases. The target analyte of this method is acetylene, with a concentration range typically between 0.1 ppm and 10 ppm.

[0057] The ionic liquid used in this embodiment is a hydrophobic ionic liquid with a high partition coefficient, high chemical stability, and low viscosity for acetylene. Specifically, it is 1-butyl-3-methylimidazolium bis(trifluoromethanesulfonyl)imide salt. The ionic liquid is used as an extractant. It utilizes its limited miscibility with the transformer oil phase and its preferential solubility for acetylene molecules to efficiently extract and enrich trace amounts of acetylene in the transformer oil phase into the ionic liquid phase. Furthermore, due to its extremely low vapor pressure, the degassing step is avoided. The ionic liquid is loaded into the ionic liquid storage tank of the system during system initialization and transported to the mixing reaction chamber through the fluid pipeline.

[0058] The first and second volumes are set to ensure acetylene extraction efficiency and meet the sensitivity requirements of subsequent detection. Typically, the volume of the transformer oil sample to be tested is set to 10 mL-50 mL (the first volume), and the volume of the ionic liquid is set to 1 mL-5 mL (the second volume). Maintaining the ratio of the first to second volumes between 10:1 and 5:1 ensures that a sufficient amount of acetylene is extracted into the ionic liquid phase while keeping the ionic liquid phase volume small, facilitating subsequent reagent addition and signal amplification, thus achieving effective enrichment.

[0059] Regarding the first temperature and the first preset time, since increasing the temperature can reduce the viscosity of the transformer oil phase and the ionic liquid phase, accelerate the mass transfer of acetylene molecules, and shorten the extraction equilibrium time, the first temperature is generally set to 40-60℃, and the first preset time is the stirring time, which is set according to the time required to reach the distribution equilibrium, usually 10-30 minutes; it is completed in the mixing reaction chamber of the system with temperature control and stirring functions, and the temperature is precisely maintained by the temperature control device.

[0060] The second preset time is after stirring is stopped, and the mixture needs to stand to allow the ionic liquid phase (density about 1.4-1.6 g / cm³) and the transformer oil phase (density about 0.8-0.9 g / cm³) with significant density differences to completely separate into two phases under the action of gravity. The second preset time is generally set to 5-15 minutes to ensure a clear interface between the two phases.

[0061] In step S200, a measuring reagent and an internal standard reagent are simultaneously added to the ionic liquid phase. Based on the first click chemical reaction of the measuring reagent in the ionic liquid phase, a first product is generated. The trigger in the internal standard reagent reacts with the second azide component in a second click chemical reaction to generate a second product.

[0062] The measuring reagent is a solution containing the first azide component, the core component of which can be 5-azido-1-methyltetrazazole. The first azide component is a tetrazazole derivative that can efficiently undergo a cycloaddition reaction with acetylene by in-situ generation of azide groups through tautomerism under copper catalysis. It is a specific reactant for acetylene, and its consumption corresponds to the amount of acetylene. In actual use, the measuring reagent is a pre-prepared organic reagent solution with a precisely calibrated concentration, which is stored in the measuring reagent storage tank of the system.

[0063] The internal standard reagent is a mixed solution containing the second azide component and the trigger. The internal standard reagent is used to provide an internal standard reaction channel that is independent of acetylene but undergoes the same subsequent process. The second azide component is used as the substrate of the internal standard reaction, and the trigger is used as its specific reactant. In actual use, the internal standard reagent is a stable solution in which the two are mixed at a fixed stoichiometric ratio and stored in the internal standard reagent storage tank of the system.

[0064] The second azide component is selected from substances that do not react with acetylene but can undergo a rapid and quantitative click reaction with a specific trigger to produce a detectable signal. In practice, azide compounds with cleavable fluorescent reporter groups are selected. In this method, DBCO-Cy5-azide is selected, which is a dibenzocyclooctylene-azide compound linked with a Cy5 fluorescent group. This substance has extremely low reactivity with acetylene under copper-free conditions, which can ensure selectivity.

[0065] The trigger is a highly reactive ring-strained alkyne that can specifically and efficiently undergo a strain-promoted azido-alkyne cycloaddition reaction with the second azide component in the internal standard reagent. This reaction does not require copper catalysis and is extremely fast. Through this reaction, a fluorescent reporter group (Cy5) attached to the second azide component can be quantitatively released, thereby generating a fixed amount of internal standard signal that can be used to trigger subsequent cascade amplification or direct fluorescence detection. The trigger is specifically BCN-PEG4-alkyne, a bicyclic [6.1.0]nonyne derivative with high ring strain.

[0066] Step S201: Add a third solution containing a copper catalyst to all the extracted ionic liquid phases, and simultaneously add a measuring reagent and an internal standard reagent. The measuring reagent contains a first azide component of known concentration, and the internal standard reagent contains a second azide component and a trigger of known concentration.

[0067] The third solution is specifically a copper sulfate solution reduced by sodium ascorbate, comprising copper sulfate, sodium ascorbate, and a buffer component. Copper sulfate provides a source of divalent copper ions, while sodium ascorbate reduces the divalent copper ions to catalytically active monovalent copper ions. The third solution provides the monovalent copper ions necessary for the first click chemical reaction, which can greatly accelerate the cycloaddition reaction rate of azide and acetylene, allowing it to proceed rapidly and quantitatively at room temperature or slightly above room temperature.

[0068] The addition of a third solution preloads a catalyst for the upcoming first-click chemical reaction, ensuring the reaction system possesses catalytic activity. The added measuring reagent provides a quantitative azide reactant that reacts with the extracted acetylene in the ionic liquid; the acetylene will react with excess azide groups, consuming an amount of azide equal to the amount of acetylene. The added internal standard reagent provides all reactants for the internal standard channel at once. The second azide component will rapidly react with a known concentration of triggering agent contained in the reagent, generating a fixed amount of the second product. This reaction is independent of the acetylene concentration, providing a stable internal reference signal for the entire detection process.

[0069] In step S202, the temperature of the ionic liquid phase is controlled at a preset second temperature, and a first click chemical reaction and a second click chemical reaction are carried out, with the reaction time being a third preset time; the first azide component in the measuring reagent undergoes a first click chemical reaction with acetylene to generate a first product; the second azide component in the internal standard reagent undergoes a second click chemical reaction with the trigger to generate a second product;

[0070] The first-click chemical reaction takes place in an ionic liquid phase in the presence of a copper catalyst, consuming an equimolar amount of the first azide component and generating the first product. In the first-click chemical reaction, the reactants are acetylene and the first azide component, the catalyst is monovalent copper ions provided by the third solution, and the product is the first product P.A It is a 1,4-disubstituted 1,2,3-triazole derivative, specifically 1-methyl-5-(1,2,3-triazol-4-yl)tetrazazole; under the catalysis of monovalent copper ions, the terminal alkyne hydrogen of acetylene is activated and undergoes a [3+2] cycloaddition reaction with the azide to generate a stable triazole ring. The first-click chemical reaction has the characteristics of high selectivity, high efficiency and high yield; the amount of azide consumed in the reaction is theoretically exactly equal to the initial total amount of acetylene in the ionic liquid phase; the reaction is carried out in the presence of excess first azide component, and the reaction terminates naturally when the limited acetylene is completely consumed. The complete reaction can be guaranteed by a third preset time that is greater than the theoretical complete reaction time.

[0071] The second click chemical reaction, in the presence of a trigger, proceeds synchronously with the first click chemical reaction in the same reaction environment, consuming a pre-defined amount of the second azide component and generating the second product. During the second click chemical reaction, the reactants are the second azide component from the internal standard reagent and the trigger in the same bottle. Under catalyst-free conditions, the second product is generated, which includes the formation of a stable triazole cycloadduct and the release of free Cy5 fluorescent molecules from the adduct through quantitative cleavage. The second click chemical reaction is a strain-promoted azide-alkyne cycloaddition reaction. The high ring strain of the trigger greatly reduces the reaction energy barrier of the cycloaddition, allowing it to react instantaneously with the second azide component at room temperature to generate a triazole ring, releasing the fluorescent reporter group Cy5 simultaneously. The amount of the second azide component and trigger consumed is determined by the initial concentration and volume of the internal standard reagent, which is a fixed internal standard constant and is independent of the initial total amount of acetylene.

[0072] Specifically, regarding the second temperature and the third preset time, the second temperature is set to ensure that both click chemical reactions proceed at the optimal rate while avoiding side reactions and excessive volatilization of ionic liquids; generally, the second temperature is set to 25-35℃. The third preset time is the time required to ensure that both click chemical reactions proceed fully to completion. For the first click chemical reaction, it is necessary to ensure that trace amounts of acetylene react completely. For the second click chemical reaction, which is extremely fast, the third preset time is generally set to 20-60 minutes to ensure that the reaction is complete and that a certain amount of the first and second products are generated.

[0073] The fixed internal scalar constant is the specific amount of the second azide component consumed by the second click chemical reaction in each complete detection cycle, expressed in moles or micromoles. Since the second click chemical reaction is carried out quantitatively and the amount of trigger is precisely controlled, the amount of the second product generated by the reaction is fixed and constant. This fixed amount is the fixed internal scalar constant.

[0074] When preparing the internal standard reagent, the concentration of the second azide component... Both the trigger concentration and the reaction trigger concentration are known parameters. To ensure complete reaction, the trigger is generally set in excess relative to the second azide component. Simultaneously, under the control of the system's reagent addition and drive module, a fixed volume is injected into the ionic liquid phase each time via a high-precision micro-injection pump or metering valve. The internal standard reagent, therefore, each time the amount of the second azide component added is measured, i.e., when the internal standard constant C is fixed, is determined by the formula... The conclusion is as follows.

[0075] In step S300, the first product and the second product are subjected to the same cascade chemical amplification reaction to release hydrogen ions. The change in conductivity after the reaction is measured to obtain the first conductivity change value and the second conductivity change value.

[0076] In step S301, the mixture containing the first and second products generated in step S203 is transferred to a signal amplification reaction cell, and an acid-sensitive substrate is pre-placed in the signal amplification reaction cell; temperature control and stirring are activated, and the temperature control device in the signal amplification reaction cell rapidly raises the temperature of the mixture and keeps it constant at the preset optimal catalytic temperature (e.g., 35°C). At the same time, magnetic stirring is activated to ensure uniform mixing. The acid-sensitive substrate pre-placed in the cell quickly dissolves and comes into contact with the catalyst, and the cascade chemical amplification reaction is immediately initiated; the first and second products are used as catalysts to catalyze the hydrolysis reaction of the acid-sensitive substrate, continuously releasing hydrogen ions.

[0077] The signal amplification reaction cell includes a sealed reaction cell made of glass or chemically inert polymer, a pair of high-precision platinum electrodes integrated into the cell wall (forming a conductivity detector), a precision temperature sensor, and a micro magnetic stir bar. This provides a uniform, stable, and controllable microenvironment for subsequent cascade chemical amplification reactions, ensuring that the first and second products can efficiently and synchronously catalyze the same acid-sensitive substrate for hydrolysis, thereby converting trace chemical events into macroscopic and easily detectable conductivity change signals.

[0078] Acid-sensitive substrates are compounds that can undergo specific hydrolysis and quantitatively release hydrogen ions under the action of a catalyst. The presence information of a single catalyst molecule is amplified tens of thousands of times and converted into a measurable change in ion concentration. In this embodiment, the molecules of the first and second products are designed to have esterase-mimicking activity, such as phosphatase-mimicking activity. Each product molecule acts as a catalyst, which can repeatedly and efficiently hydrolyze thousands of substrate molecules. The acid-sensitive substrate is specifically p-nitrophenol phosphate (pNPP). During the hydrolysis reaction, under the catalysis of the first or second product with phosphatase-mimicking activity, the phosphate ester bond in the pNPP molecule is hydrolyzed and broken to generate p-nitrophenol (pNP) and hydrogen phosphate ions. The released hydrogen phosphate ions will further undergo proton dissociation in the aqueous solution, resulting in a net increase in the concentration of free hydrogen ions in the system. The catalytic hydrolysis process has high specificity and efficiency. Each catalyst molecule converts thousands of substrate molecules per minute, thereby generating a hydrogen ion concentration change value that can be accurately detected by a conductivity electrode in a short time.

[0079] The signal amplification of the first and second products is carried out synchronously in the same reaction tank and the same mixture at the same time. Chemical groups simulating the active center of natural phosphatase are precisely introduced into the molecular structures of both the first and second products. During the hydrolysis reaction, each catalyst molecule of the first or second product is not consumed during the reaction and can be cyclically catalyzed to continuously hydrolyze pNPP into pNP and hydrogen phosphate ions, accompanied by the release of net hydrogen ions. The total amount of hydrogen ions released by the first product is proportional to its initial concentration, that is, proportional to the amount of acetylene. The total amount of hydrogen ions released by the second product is determined by its fixed internal scalar constant.

[0080] Step S302: Measure the total change in steady-state conductivity before and after the reaction, and calculate the first conductivity change value and the second conductivity change value;

[0081] First, before the cascade chemical amplification reaction begins, the initial baseline conductivity in the ionic liquid phase is measured. After the cascaded chemical amplification reaction reaches steady state, the current measured total steady-state conductivity of the mixture is measured using a conductivity detector. Through the blank correction experiment in step S402, the measured value of the second steady-state conductivity contributed solely by the second product is obtained. ;

[0082] Then, calculate the total change in steady-state conductivity measurements. , Total steady-state conductivity measurement The measured value represents the change in hydrogen ion concentration contributed by both the first and second products. The total change in steady-state conductivity is calculated from this change. It includes the hydrogen ion contribution shared by both;

[0083] Finally, the change in first conductivity value , ; Second conductivity change value , .

[0084] The initial baseline conductivity measurement refers to the inherent conductivity value of the system before the start of the cascade chemical amplification reaction, that is, when the mixture containing the first and second products has just been injected into the signal amplification reaction cell but the acid-sensitive substrate has not yet been catalytically hydrolyzed. After the temperature of the signal amplification reaction cell stabilizes, the integrated high-precision conductivity detector measures and records the stable reading, which serves as the calculation benchmark for all subsequent conductivity changes. This reading is used to deduct the contribution of background components such as ionic liquids and residual reagents to the conductivity, thereby ensuring that the measurement signal originates purely from the hydrogen ions released by the catalytic hydrolysis reaction.

[0085] The total steady-state conductivity measurement refers to the stable conductivity reading of the mixture after the cascade chemical amplification reaction has been fully carried out and reached kinetic equilibrium, that is, after the rate of hydrogen ion generation and various consumption rates have reached equilibrium. It reflects the total concentration of hydrogen ions produced by the co-catalytic hydrolysis of the first and second products and is the key raw data for calculating the total reaction signal.

[0086] To ensure that the signal amplification efficiency of the two products in the two measurement channels and the internal standard channel is the same, the setup is mainly based on the homology of molecular structures and the absolute identity of the reaction environment, and includes the following process:

[0087] First, in terms of molecular design, the catalytic active centers of the first and second products are constructed using the same chemical skeleton and ligand structure (e.g., both are based on 1,2,3-triazole and connected with the same double zinc ion chelating group), which ensures at the molecular level that the two have almost identical catalytic kinetic parameters.

[0088] Secondly, in terms of process control, the scale-up reactions of the two products are carried out in the same physicochemical environment, namely, they are mixed and reacted in the same signal amplification reaction tank, the catalytic amplification process occurs within the same time window, the catalytic reaction temperature is maintained constant by the same high-precision temperature control device, the initial concentration and total amount of acid-sensitive substrate are fixed, the ionic strength and pH of the solution are kept consistent through a buffer system, and the stirring speed is constant to ensure the same mass transfer rate. Through condition control, any factors that may affect the catalytic efficiency (such as temperature and diffusion) have the same effect on the first and second products, thus ensuring that the amplification factor K is equal both theoretically and experimentally.

[0089] Step S400: Calculate the first electrical signal value based on the obtained first conductivity change value, calculate the second electrical signal value based on the obtained second conductivity change value, and calculate the ratio of the first electrical signal value to the second electrical signal value to obtain the signal ratio.

[0090] Step S401: Obtain the first conductivity change value, linearly convert the first conductivity change value into a first voltage signal based on the internal circuit of the conductivity detector, and convert it into a digital quantity, i.e., the first electrical signal value, by the ADC.

[0091] The first conductivity change value refers to the portion of conductivity increment contributed by the acetylene-dependent first product catalytic amplification reaction in the measurement channel. It is calculated through step S302 and includes the portion attributable to the first product from the change between the initial baseline of the reaction and the total steady-state conductivity measurement value, which includes contributions from both the first and second products. That is, the conductivity increment purely derived from acetylene. It serves as a direct electrical signal input for quantifying acetylene content and is used to connect chemical and electrical quantities.

[0092] First electrical signal value It is the core digital signal used for final concentration calculation and characterizing the specific reaction amount of acetylene. It includes a digitized first voltage signal output by an analog-to-digital converter (ADC) that corresponds to the change in first conductivity. The first electrical signal value is used as the molecule in the ratio calculation, and its size is directly proportional to the amount of acetylene.

[0093] The first voltage signal is an analog electrical quantity. It is a continuous voltage output by the conductivity detection circuit after linearly converting the first conductivity change value, which facilitates circuit transmission and processing.

[0094] In step S402, after obtaining the first electrical signal value, an alkaline neutralizing solution is added to the mixture to terminate the cascade chemical amplification reaction and reset the system. Under blank conditions without acetylene, only the internal standard reagent is added, without adding the measuring reagent and the third solution. Steps S200 to S302 are repeated to obtain the second steady-state conductivity measurement value generated solely by the second product. The change in second conductivity is obtained by subtracting the initial baseline conductivity measurement from the second steady-state conductivity measurement. The internal circuitry of the conductivity detector linearly converts this second conductivity change value into a second voltage signal, which is then converted into a digital quantity, namely the second electrical signal value S, by the ADC. B .

[0095] Among them, the second electrical signal value It is a core digital signal used to characterize a fixed internal scalar, including a second voltage signal output by an analog-to-digital converter corresponding to the change in second conductivity, or a digital fluorescence intensity reading directly output by a fluorescence detector. There are two ways to obtain the second electrical signal value: one is through fluorescence detection, directly detecting the fluorescent group (such as Cy5) released after the reaction of the second azide component. This fluorescence intensity is proportional to the amount of the second product and the detection is rapid, eliminating the need for time-consuming secondary amplification reactions and conductivity measurements, allowing for direct and rapid acquisition of the second electrical signal value; the other method is to calculate it by subtracting the initial baseline conductivity measurement from the second steady-state conductivity measurement. This method requires an additional blank amplification experiment cycle. The choice between the two methods depends on the reagent requirements. For example, in systems requiring rapid online monitoring, direct fluorescence detection can be used to obtain the second electrical signal value.

[0096] When calculating the second electrical signal value by fluorescence detection, fluorescence detection is performed on the ionic liquid phase after the second product is generated; the fluorescence intensity value of the quantitatively released cleavable fluorescent reporter group is measured, and this fluorescence intensity value is used as the second electrical signal value.

[0097] The second steady-state conductivity measurement is a measured physical quantity, referring to the conductivity reading after the amplification is triggered solely by the internal standard reaction and the equilibrium is reached;

[0098] The second conductivity change value refers to the conductivity increment caused by a fixed amount of the second product alone in the internal standard channel, which is a fixed value independent of the acetylene concentration. It is used to provide a real-time, built-in reference signal and to correct system fluctuations.

[0099] The second voltage signal is an analog electrical quantity, which is the continuous voltage output corresponding to the second conductivity change value;

[0100] The second electrical signal value is a final digital quantity, which is the result of the second voltage signal after ADC conversion, or a direct digital reading of fluorescence intensity;

[0101] Alkaline neutralizing solution is a high-buffer capacity alkaline buffer solution, such as a 0.5 mol / L tris(hydroxymethyl)aminomethane buffer solution, used to rapidly and thoroughly neutralize all hydrogen ions generated in a cascade chemical amplification reaction, restoring the pH of the reaction system to its initial state (e.g., pH 7.0), thereby immediately terminating the hydrolysis catalytic reaction and resetting the conductivity to a level close to the initial baseline, preparing for subsequent individual measurements in the internal standard channel or the next detection cycle of the system.

[0102] Step S403: Calculate the quotient of the first voltage signal and the second voltage signal to obtain the signal ratio R. ;

[0103] For the first voltage signal With the second voltage signal , , Where K is the same amplification factor, G is the same conductance-to-voltage conversion factor, n is the amount of acetylene, and C is a fixed internal scalar constant; therefore Therefore, the amplification factor is canceled out in the ratio operation, and the signal ratio R is only proportional to the amount of acetylene n, while all common factors affecting K, such as temperature fluctuations and catalyst efficiency, are irrelevant. The larger the R value, the higher the acetylene concentration in the transformer oil sample to be tested.

[0104] Step S500: Based on the pre-established standard curve showing the correspondence between the signal ratio and the acetylene concentration, the acetylene concentration value in the transformer oil sample to be tested is calculated based on the signal ratio.

[0105] First, obtain N standard oil samples with known acetylene concentrations, and sequentially execute steps S100 to S404 to calculate the signal ratio of each standard oil sample. With the amount of known acetylene in each standard oil sample as the abscissa and the measured signal ratio as the ordinate, perform linear regression fitting, and the resulting linear equation is used as the standard curve of the relationship between the signal ratio and the acetylene concentration.

[0106] The linear equation is: Where n represents the amount of acetylene calculated from the curve, in mol or μmol; R is the measured signal ratio; a is the fitting slope, in mol, which is theoretically equal to the set fixed internal scalar constant C, i.e., a≈C; b is the fitting intercept, in mol, which reflects the background response of the system. The parameters a and b of the equation are stored in the system's memory.

[0107] Then, the signal ratio measured from the transformer oil sample to be tested is substituted into the linear equation of the standard curve to calculate the amount of acetylene extracted in the ionic liquid phase; the amount of acetylene n refers to the total number of acetylene gas molecules extracted from the oil sample to be tested and ultimately participating in the reaction, in moles.

[0108] Finally, based on the first volume of the transformer oil sample to be tested, the amount of acetylene is converted into the acetylene concentration value in the transformer oil sample to be tested; the unit of the final output acetylene concentration value is usually the volume fraction commonly used in the field of transformer oil dissolved gas analysis, namely ppm (μL / L), which represents the number of microliters of acetylene gas dissolved in each liter of oil under standard conditions.

[0109] After obtaining the amount of acetylene, n, it is converted using the initial volume of the transformer oil sample to be tested. The formula is as follows: ;

[0110] in, This is the molar volume of the gas, usually taken as 22.4 L / mol, which is an approximation under standard conditions. This involves converting the amount of substance to the gas volume (liters) under standard conditions, and then multiplying by 10. 6 This is to convert the unit to microliters. The concentration of acetylene in the oil sample. The amount of acetylene, expressed in mol, is obtained through a linear equation. Calculated; This is the initial volume of the transformer oil sample to be tested, i.e., the first volume, in L; the final result is the acetylene concentration in the oil expressed in ppm, which is displayed or output by the system.

[0111] In this embodiment, the difference between setting the signal ratio to determine the concentration and directly amplifying the signal to determine the concentration lies in the different anti-interference logic of the measurement principle;

[0112] If the concentration is measured by directly amplifying the signal, it is measuring an absolute physical signal, such as directly measuring the total change in the final steady-state conductivity value. Furthermore, by directly converting it into concentration through a single-point calibration curve, all the effects of influencing factors, including target reaction, environmental fluctuations, and system drift, are superimposed on this single signal. Therefore, any minute disturbances such as temperature changes, catalyst deactivation, and detector sensitivity decay will be directly misjudged as changes in acetylene concentration, resulting in large drift, poor stability, and low long-term reliability of the measurement results. This is the fundamental reason for the failure of existing methods in the background technology.

[0113] The signal ratio determination concentration of this invention measures the relative proportion of two signals. By introducing an internal standard channel that undergoes the exact same physicochemical path, any interference with the main measurement channel S is eliminated. A The common interferences will affect the second electrical signal value of the internal standard channel in exactly the same proportion. By calculating the ratio, these common interference factors are mathematically precisely canceled out. In the end, the signal ratio R is only sensitive to the difference between the two channels, that is, only sensitive to the specific reaction amount of acetylene. Therefore, the common noise is removed in principle, the specific signal is extracted, and a powerful self-correction function is achieved, thereby obtaining extremely high long-term stability, repeatability and anti-environment interference ability.

[0114] like Figure 3 As shown, the transformer oil acetylene detection system based on click chemistry includes a sample flow path and reaction control module, a reagent dosing and driving module, a signal amplification and conversion module, a signal acquisition and data processing module, and a system control and human-computer interaction module.

[0115] The sample flow path and reaction control module is used to obtain the transformer oil sample to be tested and mix it with the ionic liquid in the mixing reaction chamber, and separate the ionic liquid phase containing acetylene. The sample flow path and reaction control module includes an oil sample quantitative injection pump, an ionic liquid storage tank, a mixing reaction chamber with temperature control and stirring functions, and a phase separation unit. The oil sample quantitative injection pump is used to extract and inject a first volume of the transformer oil sample to be tested into the mixing reaction chamber. The mixing reaction chamber is used to hold a second volume of ionic liquid and perform the extraction process in step S100. The phase separation unit is used to perform the separation and transfer of the ionic liquid phase in step S100.

[0116] The reagent dosing and driving module is used to simultaneously add the measuring reagent and the internal standard reagent to the ionic liquid phase. Based on the first click chemical reaction of the measuring reagent in the ionic liquid phase, a first product is generated, and the trigger in the internal standard reagent undergoes a second click chemical reaction with the second azide component to generate a second product. The reagent dosing and driving module includes at least three independent microfluidic driving units, which are respectively connected to the copper catalyst storage tank, the measuring reagent storage tank, and the internal standard reagent storage tank. Each microfluidic driving unit is configured to precisely inject the third solution, the measuring reagent, and the internal standard reagent according to the timing and dosage of steps S201 and S202.

[0117] The signal amplification and conversion module is used to trigger the same cascade chemical amplification reaction on the first product and the second product respectively to release hydrogen ions. By measuring the change in conductivity after the reaction, the first conductivity change value and the second conductivity change value are obtained. The signal amplification and conversion module includes a signal amplification reaction cell, a conductivity detector integrated therein, and a temperature control device. The signal amplification reaction cell receives a mixture containing the first product and the second product and executes the cascade chemical amplification reaction in step S301. The conductivity detector is used to perform the conductivity measurement in step S302.

[0118] The signal acquisition and data processing module is used to calculate a first electrical signal value based on the acquired first conductivity change value, calculate a second electrical signal value based on the acquired second conductivity change value, calculate the ratio of the first electrical signal value to the second electrical signal value to obtain a signal ratio, and calculate the acetylene concentration value in the transformer oil sample to be tested based on the pre-established standard curve of the correspondence between the signal ratio and the acetylene concentration. The signal acquisition and data processing module includes an analog-to-digital converter, a microprocessor, and a memory. The analog-to-digital converter is connected to the conductivity detector and is used to digitize the voltage signal. The microprocessor is programmed to control the timing of the entire system and execute the ratio calculation in step S403 and the concentration inversion calculation in step S500. The memory is used to store the standard curve and linear equation parameters in step S500.

[0119] The system control and human-machine interaction module includes a main controller, an input device, and a display device. The main controller coordinates the operation of the sample flow path and reaction control module, as well as the reagent dosing and drive module. The input device is used to set parameters, and the display device is used to present the final acetylene concentration in the transformer oil sample to be tested.

[0120] In this embodiment, the first product generated by the first click chemical reaction and the second product generated by the second click chemical reaction both serve as catalysts to trigger the same subsequent cascade chemical amplification reaction. This allows a single product molecule to catalyze the hydrolysis of a large amount of acid-sensitive substrate, continuously releasing hydrogen ions. This leads to an exponential increase in the hydrogen ion concentration in the solution, which is ultimately reflected in a significant and measurable change in the conductivity of the mixture. This transforms the initial weak chemical event into a macroscopic and easily measurable physical signal, providing a first conductivity change value that is proportional to the acetylene content. This allows for the generation of a clear first electrical signal value far exceeding the detection threshold, even for extremely low concentrations of acetylene. This overcomes the defect of being undetectable due to weak signals and achieves highly sensitive, direct detection of acetylene in transformer oil at the ppm or even ppb level without degassing.

[0121] The dual-channel internal standard ratio detection logic enhances anti-interference capability and long-term stability. Utilizing the second click chemical reaction occurring simultaneously with the internal standard reagent and trigger, a fixed amount of the second product is generated. This reaction exists independently of the acetylene concentration detection process, but undergoes the same subsequent cascade chemical amplification reaction and signal detection process as the measurement channel, producing a second conductivity change value and a corresponding second electrical signal value. The final output is not a single first electrical signal value, but rather the ratio of the first to the second electrical signal value. Any common interference factors affecting both reaction channels simultaneously, such as reaction rate fluctuations caused by ambient temperature changes, batch-to-batch differences in copper catalyst activity, ionic liquid background conductivity drift, and detector gain changes, will proportionally affect the first and second electrical signal values. During the ratio calculation, common interferences are synchronously canceled out. The final signal ratio used for concentration inversion is only related to the specific reaction amount of acetylene and is independent of common noise. Through a built-in real-time reference system, online self-calibration is achieved, ensuring high consistency and accuracy of detection results across different times and batches of reagents.

[0122] This application also provides an electronic device. The electronic device may include one or more processors and one or more memories. The memories store computer-readable code that, when executed by the one or more processors, can perform the click chemistry-based acetylene detection method and system for transformer oil without degassing, as described above.

[0123] The methods and systems according to the embodiments of this application can also be implemented using the architecture of the electronic device shown in this application. The electronic device may include a bus, one or more CPUs, ROM, RAM, a communication port connected to a network, input / output, a hard disk, etc. The storage device in the electronic device, such as a ROM or hard disk, may store the click chemistry-based acetylene detection method and system for transformer oil without degassing provided in this application. Furthermore, the electronic device may also include a user interface. Of course, the architecture shown in this application is merely exemplary; when implementing different devices, one or more components of the electronic device shown in this application may be omitted according to actual needs.

[0124] It should be noted that, in this document, relational terms such as "first" and "second" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising a reference structure" does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes the element.

[0125] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A click chemistry-based method for detecting acetylene in transformer oil without degassing, characterized in that, The method includes: The transformer oil sample to be tested is mixed with an ionic liquid in a mixing reaction chamber, and the acetylene-containing ionic liquid phase is separated. Simultaneously add the measuring reagent and the internal standard reagent to the ionic liquid phase. Based on the first click chemical reaction of the measuring reagent in the ionic liquid phase, a first product is generated. The trigger in the internal standard reagent reacts with the second azide component to generate a second product. After triggering the same cascade chemical amplification reaction on the first and second products respectively, hydrogen ions are released. The changes in conductivity after the reaction are measured to obtain the first and second conductivity changes. A first electrical signal value is calculated based on the first change in conductivity, and a second electrical signal value is calculated based on the second change in conductivity. The ratio of the first electrical signal value to the second electrical signal value is then calculated to obtain the signal ratio. Based on a pre-established standard curve showing the relationship between signal ratio and acetylene concentration, the acetylene concentration in the transformer oil sample to be tested is calculated based on the signal ratio.

2. The method for detecting acetylene in transformer oil without degassing based on click chemistry according to claim 1, characterized in that, The process of obtaining the transformer oil sample to be tested and mixing it with the ionic liquid in a mixing reaction chamber to separate the acetylene-containing ionic liquid phase includes: A first volume of the transformer oil sample to be tested is measured and injected into a mixing reaction chamber containing a second volume of ionic liquid. The mixing reaction chamber is heated and maintained at a preset first temperature, while stirring is performed for a first preset time, so that the acetylene in the transformer oil sample to be tested is balanced between the oil phase and the ionic liquid phase. Stop stirring and let stand for the second preset time. After the ionic liquid phase and oil phase have completely separated, remove all of the ionic liquid phase.

3. The method for detecting acetylene in transformer oil without degassing based on click chemistry according to claim 2, characterized in that, The simultaneous addition of the measuring reagent and the internal standard reagent to the ionic liquid phase includes: Add a third solution containing a copper catalyst to all the extracted ionic liquid phases, and simultaneously add a measuring reagent containing a known concentration of the first azide component and an internal standard reagent containing a known concentration of the second azide component and a trigger. The temperature of the ionic liquid phase is controlled at a preset second temperature to carry out the first click chemical reaction and the second click chemical reaction, and the reaction time is a third preset time. The first click chemical reaction is carried out in an ionic liquid phase in the presence of a copper catalyst, consuming a first azide component in an amount equal to that of acetylene to generate a first product. The second click chemical reaction is carried out simultaneously in the same reaction environment in the presence of a trigger, consuming a predetermined amount of a second azide component to generate a second product.

4. The method for detecting acetylene in transformer oil without degassing based on click chemistry according to claim 1, characterized in that, The step of obtaining the first and second conductivity change values ​​by measuring the conductivity change after the reaction includes: Before the start of the cascade chemical amplification reaction, the initial baseline conductivity value in the ionic liquid phase is obtained. The mixture containing the first and second products is transferred to the signal amplification reaction cell, which is pre-filled with an acid-sensitive substrate. Using the first and second products as catalysts, acid-sensitive substrates were hydrolyzed to continuously release hydrogen ions. The total steady-state conductivity of the current mixture after the cascade chemical amplification reaction stabilized was measured. A blank correction experiment was set up to obtain the second steady-state conductivity measurement contributed only by the second product. The total change in steady-state conductivity before and after the reaction is measured, and the first and second conductivity changes are calculated using the difference method.

5. The method for detecting acetylene in transformer oil without degassing based on click chemistry according to claim 4, characterized in that, The calculation of the first electrical signal value based on the acquired first conductivity change value and the calculation of the second electrical signal value based on the acquired second conductivity change value include: The first electrical signal value is obtained by linearly transforming the first conductivity change value; After obtaining the first electrical signal value, an alkaline neutralizing solution is added to the mixture to terminate the cascade chemical amplification reaction and reset the system. Under blank conditions without acetylene, the second steady-state conductivity measurement value generated solely by the second product is obtained. The second conductivity change value is obtained by subtracting the initial baseline conductivity measurement value from the second steady-state conductivity measurement value. The second electrical signal value is obtained by linearly transforming the obtained second conductivity change value. Calculate the quotient of the first voltage signal and the second voltage signal to obtain the signal ratio.

6. The method for detecting acetylene in transformer oil without degassing based on click chemistry according to claim 1, characterized in that, The acetylene concentration value in the transformer oil sample to be tested, calculated based on the signal ratio, includes: N standard oil samples with known acetylene concentrations were obtained. The signal ratio of each standard oil sample was calculated. The amount of known acetylene in each standard oil sample was used as the abscissa, and the measured signal ratio was used as the ordinate. After linear regression fitting, the obtained linear equation was used as the standard curve of the relationship between the signal ratio and the acetylene concentration. The signal ratio measured from the transformer oil sample to be tested is substituted into the linear equation of the labeled curve to calculate the amount of acetylene extracted in the ionic liquid phase. Based on the first volume of the transformer oil sample to be tested, the amount of acetylene is converted into the acetylene concentration value in the transformer oil sample to be tested.

7. The method for detecting acetylene in transformer oil without degassing based on click chemistry according to claim 3, characterized in that, The first azide component is a tetrazolium derivative that can generate azide groups in situ through tautomerism in the presence of a copper catalyst in an ionic liquid phase and undergo a first click chemical reaction with acetylene.

8. The method for detecting acetylene in transformer oil without degassing based on click chemistry according to claim 3, characterized in that, The second azide component is an azide compound with a cleavable fluorescent reporter group attached; the second click chemistry reaction is a strain-promoted azide-alkyne cycloaddition reaction, and the trigger is a ring-strained alkyne. After the reaction, the cleavable fluorescent reporter group is quantitatively released.

9. The method for detecting acetylene in transformer oil without degassing based on click chemistry according to claim 8, characterized in that, The calculation of the second electrical signal value also includes: After the second product is generated, the ionic liquid phase is subjected to fluorescence detection. The fluorescence intensity of the quantitatively released cleavable fluorescent reporter group is measured and used as the second electrical signal value.

10. A transformer oil acetylene detection system based on click chemistry without degassing, characterized in that, The system includes: The sample flow path and reaction control module is used to obtain the transformer oil sample to be tested and the ionic liquid are mixed in the mixing reaction chamber, and the acetylene-containing ionic liquid phase is separated. The reagent dosing and driving module is used to simultaneously add measuring reagents and internal standard reagents to the ionic liquid phase to carry out click chemistry reactions and generate the first product and the second product. The signal amplification and conversion module is used to trigger the same cascade chemical amplification reaction of the first product and the second product to release hydrogen ions. The change in conductivity after the reaction is measured to obtain the change in first conductivity and the change in second conductivity. The signal acquisition and data processing module is used to calculate a first electrical signal value based on the acquired first conductivity change value, calculate a second electrical signal value based on the acquired second conductivity change value, calculate the ratio of the first electrical signal value to the second electrical signal value to obtain the signal ratio, and calculate the acetylene concentration value in the transformer oil sample to be tested through a standard curve based on the signal ratio. The system control and human-machine interaction module is used for parameter input, control and display of the sample flow path and reaction control module, reagent dosing and driving module, signal amplification and conversion module and signal acquisition and data processing module.

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