A technique for pyrolysis of ions

Abstract

The present application relates to the technical field of ion detection, and discloses a pyrolysis ion technology, which comprises the following steps: introducing a to-be-detected gas into a detection chamber, generating a controllable ionization field by means of an excitation electrode and a collection electrode; alternately applying positive and negative pulse voltages to the excitation electrode to form a positive and negative electric field to screen pyrolysis ions; monitoring the instantaneous charge amount of the collection electrode, recording the positive pulse charge peak value and the negative pulse charge valley value, obtaining a modulated charge difference through difference demodulation, and simultaneously measuring the ion arrival time interval; determining an ion arrival time window according to the electrode spacing and the pulse length, and when the modulated charge difference exceeds a threshold value and the time interval matches the window, determining that it is an effective target ion and generating a pyrolysis alarm signal; and the present application can improve the efficiency of pyrolysis ions.

Description

Technical Field

[0001] This invention relates to the field of ion detection technology, and in particular to a technique for pyrolysis of ions. Background Technology

[0002] Existing pyrolysis ion detection technologies only use a single polarity electric field for driving, which cannot achieve accurate separation and screening of positive and negative pyrolysis ions. This easily leads to mutual interference between ions and mixed detection signals, directly resulting in a significant decrease in the accuracy of target ion identification and insufficient stability of signal acquisition.

[0003] Traditional detection schemes do not incorporate time-matching mechanisms based on ion migration characteristics, nor do they eliminate background interference through charge difference demodulation. As a result, they have poor noise suppression, lack multiple verifications for alarm judgment, and suffer from prominent false alarms and missed alarms. Consequently, the detection response speed and result reliability fail to meet the standards. Therefore, improving the efficiency of pyrolysis ion detection has become an urgent problem to be solved. Summary of the Invention

[0004] This invention provides a technique for pyrolysis of ions to solve the problems mentioned in the background art.

[0005] To achieve the above objectives, the present invention provides a technique for pyrolysis of ions, comprising: A1. The gas to be tested is introduced into a detection chamber, and a controllable ionization field is generated in the detection chamber based on the excitation electrode and collection electrode placed in the detection chamber. A2. Apply positive and negative pulse voltages alternately to the excitation electrode to generate positive and reverse electric fields alternately in the controllable ionization field. The positive electric field drives the positively charged pyrolysis ions in the gas to be tested toward the collection electrode, and the reverse electric field drives the negatively charged pyrolysis ions in the gas to be tested toward the excitation electrode. The pyrolysis ions of the gas to be tested are then obtained on the collection electrode after screening. A3. Monitor the amount of instantaneous charge accumulated on the collecting electrode, and record the peak value of the positive pulse charge and the valley value of the reverse pulse charge at the end of the positive electric field and the reverse electric field, respectively. A4. Demodulate the difference between the absolute values ​​of the peak value of the positive pulse charge and the valley value of the reverse pulse charge to obtain the modulation charge difference of the gas under test, and measure the time interval from the start of the positive electric field to the occurrence of the peak value of the positive pulse charge. A5. Based on the fixed distance between the excitation electrode and the collection electrode and the fixed duration of the positive polarity pulse voltage, determine the ion arrival time window of the gas to be tested. When the modulation charge difference exceeds the preset charge threshold, match the time interval with the ion arrival time window. A6. If the time interval falls within the ion arrival time window, a pyrolysis alarm signal for the gas to be tested will be generated based on the determination that the pyrolysis ions after screening are effective target ions.

[0006] In a preferred embodiment, the step of introducing the gas to be tested into a detection chamber and generating a controllable ionization field in the detection chamber based on the excitation electrode and collection electrode placed inside the detection chamber includes: A non-radioactive ionization source is set up in the detection chamber, and the gas to be tested is subjected to gradient thermal dissociation through the non-radioactive ionization source to obtain the pre-ionized gas to be tested. Adjust the geometry of the excitation electrode and the surface potential of the collection electrode in the detection chamber, and construct a uniformly distributed ionization region in the detection chamber according to the gas to be measured after pre-ionization; Based on the electric field intensity distribution characteristics of the ionization region, the power supply frequency of the excitation electrode is dynamically adjusted to generate a controllable ionization field in the detection chamber.

[0007] In a preferred embodiment, the alternating application of positive and negative polarity pulse voltages to the excitation electrode generates alternating positive and reverse electric fields within a controllable ionization field. The positive electric field drives positively charged pyrolysis ions in the test gas toward the collecting electrode, while the reverse electric field drives negatively charged pyrolysis ions in the test gas toward the excitation electrode. The filtered pyrolysis ions of the test gas are then obtained at the collecting electrode. This process includes: Based on the molecular polarity characteristics of the gas to be tested, a pulse width modulation signal of positive polarity pulse voltage is generated; The pulse width modulation signal is transmitted to the driving circuit of the excitation electrode to control the periodic transition of the surface potential of the excitation electrode, so as to generate a positive electric field of controllable ionization. Under the influence of a positive electric field, the positively charged pyrolysis ions in the gas to be tested are driven away from the excitation electrode by the electrophoretic migration of the positively charged pyrolysis ions in the direction of the collecting electrode, and a positive migration charge is induced on the collecting electrode. When the positive electric field ends, a polarity switching command for generating a negative polarity pulse voltage is generated, reversing the potential difference between the excitation electrode and the collection electrode to construct a reverse electric field for a controllable ionization field. By using a reverse electric field, negatively charged pyrolysis ions in the gas to be tested are bound to the surface of the excitation electrode to form a space charge layer, and the reverse diffusion of negatively charged pyrolysis ions to the collection electrode is blocked, so as to obtain the pyrolysis ions after screening of the gas to be tested.

[0008] In a preferred embodiment, the step of using the electrophoretic migration of positively charged pyrolysis ions in the gas to be tested along the direction of the collecting electrode under the action of a positive electric field to drive the positively charged pyrolysis ions away from the excitation electrode and induce a positive migration charge on the collecting electrode includes: Under the influence of a positive electric field, the gas flow rate parameters in the detection chamber are monitored, and the relaxation time of positively charged pyrolysis ions in electrophoretic migration is determined based on the gas flow rate parameters. By performing time-frequency mapping on the relaxation time, the frequency modulation command of the positive polarity pulse voltage is obtained; According to the frequency modulation command, the oscillation frequency of the pulse width modulation signal is adjusted so that the switching frequency and relaxation time of the positive electric field are in the resonance range. By utilizing the electric field force within the resonance range, positively charged pyrolysis ions are driven to undergo directional acceleration, overcoming the fluid resistance generated by the flow of the gas under test. When positively charged pyrolysis ions collide with the surface of the collecting electrode, charge capture occurs on the collecting electrode, resulting in positively transferred charge on the collecting electrode.

[0009] In a preferred embodiment, the monitoring and collection of instantaneous charge accumulated on the electrodes, and the recording of the peak value of the positive pulse charge and the valley value of the reverse pulse charge at the end of the positive and reverse electric fields, respectively, includes: The instantaneous current signal output from the collecting electrode is subjected to impedance transformation to obtain the instantaneous voltage signal corresponding to the instantaneous current signal, and the instantaneous voltage signal is subjected to analog-to-digital conversion to obtain the digital sampling sequence of the instantaneous voltage signal; The digital sampling sequence is subjected to sliding window filtering, and the maximum voltage amplitude in the digital sampling sequence is locked at the end of the positive electric field, which is taken as the positive pulse charge peak of the positive electric field. The minimum voltage amplitude in the digital sampling sequence is locked at the end of the reverse electric field, and is used as the reverse pulse charge valley value of the reverse electric field.

[0010] In a preferred embodiment, the step of demodulating the difference between the absolute values ​​of the positive pulse charge peak and the negative pulse charge valley to obtain the modulation charge difference of the gas under test, and measuring the time interval from the start of the positive electric field to the occurrence of the positive pulse charge peak, includes: Morphological analysis was performed on the positive electric field response waveform before and after the appearance of the positive pulse charge peak to obtain the positive waveform morphological feature set of the gas under test; The reverse electric field response waveform before and after the appearance of the reverse pulse charge valley is compared with the pre-stored standard interference ion waveform template for pattern recognition to obtain the background interference characteristics of the reverse electric field response waveform. Based on the logical NOT result of the positive waveform morphology feature set and the background interference feature, the absolute values ​​of the positive pulse charge peak and the negative pulse charge valley are weighted and fused to obtain the modulation charge difference of the gas under test. The first timestamp is marked at the moment the positive electric field begins, and the second timestamp is marked at the moment the peak of the positive pulse charge appears; The time difference between the second timestamp and the first timestamp is used as the time interval from the start of the positive electric field to the occurrence of the peak of the positive pulse charge.

[0011] In a preferred embodiment, the formula for calculating the modulation charge difference is as follows: ; In the formula, To modulate the charge difference, The peak value of the positive pulse charge. The valley value of the reverse pulse charge. The preset morphological-interference coupling coefficient, This refers to the positive morphological scalar factor extracted from the set of positive waveform morphological features. This refers to the interference intensity scalar factor extracted from background interference features. To take the absolute value.

[0012] In a preferred embodiment, determining the ion arrival time window of the gas to be tested based on the fixed distance between the excitation electrode and the collection electrode and the fixed duration of the positive polarity pulse voltage, and matching the time interval with the ion arrival time window when the modulation charge difference exceeds a preset charge threshold, includes: Based on the fixed spacing between the excitation electrode and the collection electrode and the fixed duration of the positive polarity pulse voltage, combined with the ambient temperature and gas pressure parameters in the detection chamber, a standard migration time reference set for various ions in the gas to be tested is generated. Thresholds are defined on the standard migration time reference set to obtain the ion arrival time window of the gas to be measured; The amplitude of the modulation charge difference is monitored in real time. When the amplitude of the modulation charge difference exceeds the preset charge threshold, the time interval is matched with the ion arrival time window.

[0013] In a preferred embodiment, if the time interval falls within the ion arrival time window, a pyrolysis alarm signal for the gas to be tested is generated based on the determination result that the screened pyrolysis ions are valid target ions, including: Based on the matching result between the time interval and the ion arrival time window, the characteristic pulse signal of the target ion in the gas to be tested is obtained; Based on the polarity attribute of the target ion characteristic pulse signal, the corresponding target ion polarity parameter is retrieved from the preset ion polarity feature library; The polarity parameters of the target ion are compared with the charge properties of the screened pyrolysis ions to obtain the ion validity verification signal of the gas to be tested. Based on the ion validity verification signal, a pyrolysis alarm signal for the gas to be tested is generated.

[0014] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention constructs a controllable ionization field within the detection chamber and alternately applies positive and negative polarity pulse voltages to the excitation electrode, precisely driving the directional migration of positive and negative pyrolysis ions. This achieves efficient separation and screening of target ions, ensuring that the collection electrode acquires high-purity screened pyrolysis ions, thus guaranteeing the purity of the detection signal from the source. By real-time monitoring of the instantaneous charge on the collection electrode, the peak value of the positive pulse charge and the valley value of the reverse pulse charge are precisely located. Combined with a difference demodulation algorithm, the modulated charge difference is obtained, effectively extracting the valid detection signal and significantly improving the accuracy and stability of signal acquisition. Simultaneously, based on the fixed electrode spacing and the duration of the positive polarity pulse voltage, the ion arrival time window is defined, and the ion migration time interval is accurately measured, providing a standardized and scientific reference for determining the effectiveness of target ions, making the detection judgment logic more rigorous and the results more reliable.

[0015] 2. This invention employs a dual verification mechanism combining modulated charge difference threshold judgment and ion arrival time window matching. This mechanism accurately identifies effective target ions, significantly improving the accuracy and reliability of pyrolysis alarm signal generation and fundamentally optimizing detection and judgment effects. Through dynamic adjustment of electric field parameters and resonance matching of ion relaxation time, the directional migration speed of pyrolysis ions is accelerated, shortening the detection response time and comprehensively improving the operational efficiency of the detection process. The non-radioactive ionization source, combined with the construction of a uniform ionization region, ensures a safe and stable detection process while adapting to the detection characteristics of different analytes. This comprehensively improves the overall efficiency and detection quality of pyrolysis ion detection, providing efficient, stable, and accurate technical support for gas pyrolysis ion detection and achieving optimization and upgrading of the entire detection process. Attached Figure Description

[0016] Figure 1 This is a schematic flowchart of a pyrolysis ion technology provided in an embodiment of the present invention; The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0017] It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

[0018] This application provides a pyrolysis ion technology. The execution entity of this pyrolysis ion technology includes, but is not limited to, at least one of the following electronic devices that can be configured to execute the technology provided in this application: a server, a terminal, or other similar device. In other words, the pyrolysis ion technology can be executed by software or hardware installed on a terminal device or a server device. The server includes, but is not limited to, a single server, a server cluster, a cloud server, or a cloud server cluster. The server can be an independent server or a cloud server that provides basic cloud computing services such as cloud services, cloud databases, cloud computing, cloud functions, cloud storage, network services, cloud communication, middleware services, domain name services, security services, content delivery networks (CDN), and big data and artificial intelligence platforms.

[0019] Reference Figure 1 The diagram shown is a flowchart illustrating a pyrolysis ion technology according to an embodiment of the present invention. In this embodiment, the pyrolysis ion technology includes: A1. The gas to be tested is introduced into a detection chamber, and a controllable ionization field is generated in the detection chamber based on the excitation electrode and collection electrode placed in the detection chamber. In this embodiment of the invention, the step of introducing the gas to be tested into a detection chamber and generating a controllable ionization field in the detection chamber based on the excitation electrode and collection electrode placed inside the detection chamber includes: A non-radioactive ionization source is set up in the detection chamber, and the gas to be tested is subjected to gradient thermal dissociation through the non-radioactive ionization source to obtain the pre-ionized gas to be tested. Adjust the geometry of the excitation electrode and the surface potential of the collection electrode in the detection chamber, and construct a uniformly distributed ionization region in the detection chamber according to the gas to be measured after pre-ionization; Based on the electric field intensity distribution characteristics of the ionization region, the power supply frequency of the excitation electrode is dynamically adjusted to generate a controllable ionization field in the detection chamber.

[0020] The non-radioactive ionization source is fixedly installed inside the detection chamber, placing it at the center of the chamber. After being powered on, the non-radioactive ionization source continuously generates a thermal field. By gradually increasing the output heat of the non-radioactive ionization source, the heat gradually increases at a fixed rate, gradually heating the gas to be tested. This achieves the gradual decomposition of the gas molecules, completing the gradient thermal dissociation operation of the gas to be tested, and finally obtaining the pre-ionized gas to be tested.

[0021] The excitation electrodes are installed on both sides of the inner wall of the detection chamber. The length of the excitation electrodes is adjusted to make the ends of the excitation electrodes flush with the side wall of the detection chamber. The spacing of the excitation electrodes is adjusted to make the distance between adjacent excitation electrodes consistent, thus completing the adjustment of the geometry of the excitation electrodes. The collection electrode is installed at the bottom of the detection chamber. The output voltage of the external power supply device for the collection electrode is adjusted to maintain a stable charge state on the surface of the collection electrode, thus achieving the adjustment of the surface potential of the collection electrode. When the gas to be tested flows in the detection chamber after pre-ionization, under the combined action of the excitation electrode and the collection electrode, the gas to be tested after pre-ionization forms a uniformly distributed ionization region inside the detection chamber.

[0022] The electric field intensity values ​​at different locations within the ionization region are collected and compared. When there are differences in the electric field intensity values ​​at different locations, the power supply frequency of the excitation electrode is adjusted according to the direction of change of the electric field intensity value. When the electric field intensity value is too high, the power supply frequency of the excitation electrode is reduced, and when the electric field intensity value is too low, the power supply frequency of the excitation electrode is increased. The operation of electric field intensity collection and power supply frequency adjustment is continuously performed until the electric field intensity values ​​at all locations within the ionization region are consistent, and finally a controllable ionization field of the detection chamber is generated.

[0023] The beneficial effects include achieving gradient thermal dissociation of the test gas through a non-radioactive ionization source, enabling pre-ionization of the test gas without the use of radioactive materials, thus improving the safety and environmental friendliness of the detection process. Precise adjustment of the excitation electrode geometry and the surface potential of the collection electrode allows for the formation of a uniform ionization region in the detection chamber after pre-ionization, avoiding detection deviations caused by uneven ionization region distribution. Dynamic adjustment of the excitation electrode power supply frequency based on the electric field intensity distribution of the ionization region stably constructs a controllable ionization field, ensuring the stability and consistency of the ionization process, resulting in higher accuracy and reliability of subsequent gas detection results. Furthermore, the entire implementation process is fully reproducible, with no unclear or unexecutable steps, meeting the continuous use requirements of practical detection scenarios.

[0024] A2. Apply positive and negative pulse voltages alternately to the excitation electrode to generate positive and reverse electric fields alternately in the controllable ionization field. The positive electric field drives the positively charged pyrolysis ions in the gas to be tested toward the collection electrode, and the reverse electric field drives the negatively charged pyrolysis ions in the gas to be tested toward the excitation electrode. The pyrolysis ions of the gas to be tested are then obtained on the collection electrode after screening. In this embodiment of the invention, the alternating application of positive and negative polarity pulse voltages to the excitation electrode generates alternating positive and reverse electric fields within a controllable ionization field. The positive electric field drives positively charged pyrolysis ions in the test gas toward the collecting electrode, while the reverse electric field drives negatively charged pyrolysis ions in the test gas toward the excitation electrode. The filtered pyrolysis ions of the test gas are then obtained at the collecting electrode. This process includes: Based on the molecular polarity characteristics of the gas to be tested, a pulse width modulation signal of positive polarity pulse voltage is generated; The pulse width modulation signal is transmitted to the driving circuit of the excitation electrode to control the periodic transition of the surface potential of the excitation electrode, so as to generate a positive electric field of controllable ionization. Under the influence of a positive electric field, the positively charged pyrolysis ions in the gas to be tested are driven away from the excitation electrode by the electrophoretic migration of the positively charged pyrolysis ions in the direction of the collecting electrode, and a positive migration charge is induced on the collecting electrode. When the positive electric field ends, a polarity switching command for generating a negative polarity pulse voltage is generated, reversing the potential difference between the excitation electrode and the collection electrode to construct a reverse electric field for a controllable ionization field. By using a reverse electric field, negatively charged pyrolysis ions in the gas to be tested are bound to the surface of the excitation electrode to form a space charge layer, and the reverse diffusion of negatively charged pyrolysis ions to the collection electrode is blocked, so as to obtain the pyrolysis ions after screening of the gas to be tested.

[0025] The process of using the electrophoretic migration of positively charged pyrolysis ions in the gas under a positive electric field to drive the positively charged pyrolysis ions away from the excitation electrode and induce a positive migration charge on the collection electrode includes: Under the influence of a positive electric field, the gas flow rate parameters in the detection chamber are monitored, and the relaxation time of positively charged pyrolysis ions during electrophoretic migration is determined based on the gas flow rate parameters. By performing time-frequency mapping on the relaxation time, the frequency modulation command of the positive polarity pulse voltage is obtained; According to the frequency modulation command, the oscillation frequency of the pulse width modulation signal is adjusted so that the switching frequency and relaxation time of the positive electric field are in the resonance range. By utilizing the electric field force within the resonance range, positively charged pyrolysis ions are driven to undergo directional acceleration, overcoming the fluid resistance generated by the flow of the gas under test. When positively charged pyrolysis ions collide with the surface of the collecting electrode, charge capture occurs on the collecting electrode, resulting in positively transferred charge on the collecting electrode.

[0026] To detect the molecular polarity of the gas to be tested, the gas molecule polarity detection device is used to compare it with a standard gas sample of known polarity to determine the polarity type of the gas molecules to be tested. Based on the determined polarity characteristics of the gas molecules to be tested, a pulse signal generator is started and the output polarity of the pulse signal generator is adjusted to positive. By controlling the duty cycle of the output signal of the pulse signal generator, a pulse width modulation signal of positive polarity pulse voltage is generated.

[0027] The pulse width modulation signal of the generated positive polarity pulse voltage is transmitted to the driving circuit of the excitation electrode through a dedicated signal transmission line. After receiving the pulse width modulation signal, the driving circuit controls the on / off state and amplitude of its own output voltage according to the high and low level changes of the signal. In turn, it controls the potential on the surface of the excitation electrode to undergo periodic transitions of high and low according to the periodic law of the pulse width modulation signal. Through these periodic transitions of potential, a positive electric field with controllable ionization is generated in the detection chamber.

[0028] During the continuous application of a positive electric field to the detection chamber, gas velocity sensors are installed at the inlet and outlet of the detection chamber. The gas velocity sensors collect the flow velocity data of the gas to be tested in the detection chamber in real time, which is the gas velocity parameter. Based on the collected gas velocity parameters, the magnitude of the fluid resistance generated by the flow of the gas to be tested on the positively charged pyrolysis ions is determined. Combined with the migration characteristics of the positively charged pyrolysis ions in the positive electric field, the relaxation time required for the positively charged pyrolysis ions to overcome the fluid resistance and reach a stable migration state during electrophoretic migration is determined.

[0029] The time signal corresponding to the determined relaxation time is input into the time-frequency mapping module. The time-frequency mapping module converts the time dimension signal of the relaxation time and maps the time signal into the corresponding frequency signal. Based on the mapped frequency signal and combined with the output requirements of the positive polarity pulse voltage, a frequency modulation command that can adjust the frequency of the positive polarity pulse voltage is generated.

[0030] The frequency modulation command is transmitted to the pulse signal generator. The pulse signal generator adjusts the oscillation frequency of its output pulse width modulation signal according to the frequency modulation command. It continuously adjusts the oscillation frequency and simultaneously monitors the matching status of the switching frequency and relaxation time of the positive electric field until the switching frequency and relaxation time of the positive electric field are completely matched, so that the switching frequency and relaxation time of the positive electric field are in the resonance range.

[0031] A stable and continuous electric field force is generated by the positive electric field within the resonance range. This electric field force acts directionally on the positively charged pyrolysis ions, driving the positively charged pyrolysis ions to move in a directional and accelerated manner along the direction of the positive electric field. By continuously accelerating, the kinetic energy of the positively charged pyrolysis ions is increased, so that the kinetic energy of the positively charged pyrolysis ions is sufficient to overcome the fluid resistance generated by the flow of the gas to be measured, ensuring that the positively charged pyrolysis ions can continuously migrate towards the collecting electrode.

[0032] Positively charged pyrolysis ions are continuously accelerated in a directional manner under the drive of an electric field until they collide with the surface of the collecting electrode. The surface of the collecting electrode has the ability to capture charges. When positively charged pyrolysis ions collide with the surface of the collecting electrode, the collecting electrode adsorbs and retains the positive charge carried by the ions. The captured charge information is recorded by the charge detection component of the collecting electrode to obtain the positive migration charge of the collecting electrode.

[0033] The duration of the positive electric field is set by the time control module. When the time control module detects that the duration of the positive electric field has reached the preset duration, it determines that the positive electric field has ended. At this time, the time control module triggers the polarity switching command generation module to generate a polarity switching command for a negative polarity pulse voltage. This polarity switching command is transmitted to the power supply control circuit of the excitation electrode and the collection electrode. The power supply control circuit reverses the direction of the potential difference between the excitation electrode and the collection electrode according to the command, thereby constructing a controllable ionization field in the detection chamber.

[0034] A reverse electric field continuously acts within the detection chamber. Under the influence of the electric field force of the reverse electric field, negatively charged pyrolysis ions in the gas to be tested are attracted and move towards the excitation electrode, eventually attaching to and binding to the surface of the excitation electrode. A large number of negatively charged pyrolysis ions accumulate on the surface of the excitation electrode to form a space charge layer. At the same time, the repulsive force generated by the reverse electric field acts on the negatively charged pyrolysis ions, blocking the reverse diffusion of the negatively charged pyrolysis ions towards the collection electrode, leaving only positively charged pyrolysis ions in the detection chamber, thus obtaining the pyrolysis ions after screening of the gas to be tested.

[0035] The beneficial effects include the precise generation of pulse width modulation signals based on the polarity characteristics of the gas molecules to be tested, ensuring the specificity and stability of the positive electric field. A positive electric field is constructed by controlling the periodic transitions of the potential on the surface of the excitation electrode. The relaxation time is determined by combining gas flow rate parameters, and resonance between the electric field switching frequency and the relaxation time is achieved. This effectively drives positively charged pyrolysis ions to overcome fluid resistance and complete directional migration, ensuring the effective capture of positively migrating charges. After the positive electric field ends, a reverse electric field is constructed by reversing polarity, which can precisely bind negatively charged pyrolysis ions and block their reverse diffusion, achieving efficient screening of pyrolysis ions. The entire implementation process is clear, reproducible, and free of ambiguous operational steps, effectively improving the accuracy and reliability of ion screening. This provides high-quality screened pyrolysis ions for the subsequent accurate detection of the gas to be tested, while avoiding interference from irrelevant ions, further ensuring the accuracy of the detection results.

[0036] A3. Monitor the amount of instantaneous charge accumulated on the collecting electrode, and record the peak value of the positive pulse charge and the valley value of the reverse pulse charge at the end of the positive electric field and the reverse electric field, respectively. In this embodiment of the invention, the monitoring of the instantaneous charge accumulated on the collecting electrode, and the recording of the peak value of the positive pulse charge and the valley value of the reverse pulse charge at the end of the positive and reverse electric fields, respectively, includes: The instantaneous current signal output from the collecting electrode is subjected to impedance transformation to obtain the instantaneous voltage signal corresponding to the instantaneous current signal, and the instantaneous voltage signal is subjected to analog-to-digital conversion to obtain the digital sampling sequence of the instantaneous voltage signal; The digital sampling sequence is subjected to sliding window filtering, and the maximum voltage amplitude in the digital sampling sequence is locked at the end of the positive electric field as the positive pulse charge peak value of the positive electric field. The minimum voltage amplitude in the digital sampling sequence is locked at the end of the reverse electric field, and is used as the reverse pulse charge valley value of the reverse electric field.

[0037] The instantaneous current signal output from the collecting electrode is connected to an operational amplifier circuit with high input impedance. This circuit converts the output impedance of the current signal, enabling the circuit output to generate an instantaneous voltage signal that perfectly corresponds to the changing trend of the instantaneous current signal.

[0038] The instantaneous voltage signal obtained after impedance transformation is input into an analog-to-digital converter. The value of the instantaneous voltage signal is continuously acquired at fixed time intervals, and the continuously changing instantaneous voltage signal is converted into discrete digital values ​​to form a digital sampling sequence of the instantaneous voltage signal.

[0039] The obtained digital sampling sequence is sequentially truncated into continuous data segments of fixed length. After each segment is truncated, all digital values ​​within the segment are compared one by one and the average value is calculated. Then, the average value is used to replace the digital value at the center of the corresponding data segment. This process is repeated to complete the sliding window filtering of the entire digital sampling sequence.

[0040] When the continuous state of the positive electric field is detected to have ended, the update operation of the digital sampling sequence is immediately stopped. From the digital sampling sequence after sliding window filtering, all values ​​are compared one by one in descending order to determine the voltage amplitude with the largest value. This amplitude is locked as the positive pulse charge peak value of the positive electric field.

[0041] When the continuous state of the reverse electric field is detected to have terminated, the update operation of the digital sampling sequence is immediately stopped. From the digital sampling sequence after sliding window filtering, all values ​​are compared one by one in ascending order to determine the voltage amplitude with the smallest value. This amplitude is locked as the reverse pulse charge valley value of the reverse electric field.

[0042] The beneficial effects are as follows: by performing impedance transformation and analog-to-digital conversion on the output signal of the collecting electrode, the changing characteristics of the instantaneous current signal can be completely preserved and converted into a processable digital sampling sequence. By using a filtering method that slides and truncates data segments of fixed length and replaces the center value with the average value, abnormal values ​​in the digital sampling sequence can be effectively eliminated, ensuring the stability and accuracy of the data. At the end of the forward and reverse electric fields, the maximum and minimum voltage amplitudes in the corresponding sequences are locked respectively, which can accurately obtain the peak value of the forward pulse charge and the valley value of the reverse pulse charge, avoiding the interference of signal fluctuations on the results during the continuous electric field. The entire signal processing flow is clear and reproducible, and can stably achieve accurate extraction and identification of electric field-related charge signal characteristics, providing a reliable basis for subsequent data judgment.

[0043] A4. Demodulate the difference between the absolute values ​​of the peak value of the positive pulse charge and the valley value of the reverse pulse charge to obtain the modulation charge difference of the gas under test, and measure the time interval from the start of the positive electric field to the occurrence of the peak value of the positive pulse charge. In this embodiment of the invention, the step of demodulating the difference between the absolute values ​​of the positive pulse charge peak and the negative pulse charge valley to obtain the modulation charge difference of the gas under test, and measuring the time interval from the start of the positive electric field to the occurrence of the positive pulse charge peak, includes: Morphological analysis was performed on the positive electric field response waveform before and after the appearance of the positive pulse charge peak to obtain the positive waveform morphological feature set of the gas under test; The reverse electric field response waveform before and after the appearance of the reverse pulse charge valley is compared with the pre-stored standard interference ion waveform template for pattern recognition to obtain the background interference characteristics of the reverse electric field response waveform. Based on the logical NOT result of the positive waveform morphology feature set and the background interference feature, the absolute values ​​of the positive pulse charge peak and the negative pulse charge valley are weighted and fused to obtain the modulation charge difference of the gas under test. The first timestamp is marked at the moment the positive electric field begins, and the second timestamp is marked at the moment the peak of the positive pulse charge appears; The time difference between the second timestamp and the first timestamp is used as the time interval from the start of the positive electric field to the occurrence of the peak of the positive pulse charge.

[0044] The formula for calculating the modulation charge difference is as follows: ; In the formula, To modulate the charge difference, The peak value of the positive pulse charge. The valley value of the reverse pulse charge. The preset morphological-interference coupling coefficient, This refers to the positive morphological scalar factor extracted from the set of positive waveform morphological features. This refers to the interference intensity scalar factor extracted from background interference features. To take the absolute value.

[0045] When the electric field driving signal continuously transitions from a positive driving level state to a negative driving level state, and the duration of the negative driving level state reaches the duration for determining the stability of the electric field state, this moment is the end time of the positive electric field.

[0046] The stable electric field state determination time was determined through multiple electric field switching experiments. In the experiment, the shortest duration during which the signal no longer fluctuated after the electric field level switching was recorded. This time was used as a fixed determination time to eliminate the influence of level jitter at the moment of electric field switching on the determination of time.

[0047] When the electric field driving signal continuously transitions from the reverse driving level state to the non-reverse driving level state, and the duration of the non-reverse driving level state reaches the duration for determining the stability of the electric field state, this moment is the end time of the reverse electric field.

[0048] The positive electric field response waveforms are retrieved for a fixed duration before and after the occurrence of the positive pulse charge peak. This fixed duration is determined through typical response experiments of the gas under test to ensure complete coverage of the complete change process of the signal under the action of the positive electric field. The rising trend, falling trend, waveform duration, and waveform amplitude distribution of this waveform segment are analyzed and recorded one by one. All the characteristic data obtained from the analysis and recording are summarized and combined to obtain the positive waveform morphology feature set of the gas under test.

[0049] The reverse electric field response waveform, with a fixed duration before and after the occurrence of the reverse pulse charge valley, is compared point-by-point with a pre-stored standard interfering ion waveform template. The preset waveform matching allowable range is calibrated through multiple interfering ion detection experiments. The maximum allowable difference between the interfering waveform obtained from multiple experiments and the template waveform is used as a fixed judgment range. When the numerical difference at the corresponding point of the waveform is within the preset waveform matching allowable range, the waveform feature is determined to be a matching feature. All matching features are summarized to obtain the background interference features of the reverse electric field response waveform.

[0050] At the instant when the positive electric field is started and the electric field driving signal reaches the electric field start-up judgment level, the electric field start-up judgment level is the lowest level value at which the electric field can be stably established. This level value is determined by hardware circuit testing. The moment of this instant is marked and stored. The time after this mark is the first timestamp marked when the positive electric field starts.

[0051] At the instant the positive pulse charge peak is detected, the moment of that instant is marked and stored. The time after this mark is the second timestamp of the moment the positive pulse charge peak appears.

[0052] The time difference is calculated by comparing the time value corresponding to the second timestamp with the time value corresponding to the first timestamp. The time difference is obtained by subtracting the earlier time value from the later time value. This time difference is the time interval between the start of the positive electric field and the time when the peak of the positive pulse charge appears.

[0053] The modulated charge difference is the quantitative characteristic value of the gas under test obtained from the final calculation of the formula. This value is calculated by integrating the parameters in the formula in sequence according to the specified calculation steps, and is used to intuitively characterize the difference in effective charge response of the gas under test under the action of an electric field.

[0054] The positive pulse charge peak originates from the maximum voltage amplitude in the digital sampling sequence after sliding window filtering, which is locked at the end of the positive electric field. This amplitude is the core feature value extracted after the instantaneous current signal output by the collecting electrode under the action of the positive electric field is transformed into an instantaneous voltage signal through impedance transformation, and then converted into a digital sampling sequence through analog-to-digital conversion.

[0055] The reverse pulse charge valley value is derived from the minimum voltage amplitude in the digital sampling sequence after sliding window filtering, which is locked at the end of the reverse electric field. This amplitude is the core feature value extracted after the instantaneous current signal output by the collecting electrode under the action of the reverse electric field is transformed into an instantaneous voltage signal through impedance transformation, and then converted into a digital sampling sequence through analog-to-digital conversion.

[0056] The absolute value extraction method involves reading the original values ​​of the positive pulse charge peak and the reverse pulse charge valley, removing the positive and negative attributes of the two values, and retaining only the magnitude of the values ​​themselves, thus completing the extraction of the absolute value of a single feature value.

[0057] The preset morphology-interference coupling coefficient was determined by fitting historical data from multiple sets of experimental tests on the target gas and standard interference ion control experiments. During the experiment, the electric field driving parameters and detection environment parameters were fixed, and the effective charge response data under different waveform morphologies and interference intensities were recorded. After matching and sorting multiple sets of corresponding data, the fixed value of the coefficient was determined to unify and coordinate the influence of waveform morphology characteristics and background interference characteristics on the calculation results.

[0058] The positive morphological scalar factor is extracted from the positive waveform morphological features obtained from the positive electric field response waveform analysis. By uniformly quantifying and integrating multiple feature data such as the trend of waveform rise, trend of waveform fall, waveform duration, and amplitude distribution, the multi-dimensional morphological features are transformed into a single scalar value. The integration is based on the fixed correlation rules between the waveform morphology of the gas under test and the charge response.

[0059] The interference intensity scalar factor is extracted from the background interference features obtained by the reverse electric field response waveform pattern identification. The interference matching state is converted into a single scalar value by quantifying the matching degree between the reverse electric field response waveform and the pre-stored standard interference ion waveform template point by point. The quantification is based on the difference judgment rule between the interference waveform and the waveform to be measured.

[0060] The operation within the parentheses first reads the positive morphological scalar factor and the interference intensity scalar factor, subtracts the latter value from the former value to obtain the feature difference, then multiplies the difference with the morphological-interference coupling coefficient to obtain the product result, and finally adds the product result to the value 1 to complete the calculation of the overall value within the parentheses.

[0061] The overall formula first calculates the difference between the absolute value of the peak value of the positive pulse charge and the absolute value of the valley value of the reverse pulse charge. Then, it multiplies this difference by the value calculated in parentheses. The final product is the modulation charge difference.

[0062] This formula can correlate and fuse the peak value of the positive pulse charge and the valley value of the reverse pulse charge obtained from the previous signal processing with the positive waveform morphological feature set and background interference features obtained from waveform analysis. It eliminates the interference of positive and negative voltage attributes on the calculation results through absolute value operation, balances the influence weight of the gas waveform characteristics and background interference through the morphology-interference coupling coefficient, and achieves the logical non-elimination effect of background interference through scalar factor difference operation. This ensures that the calculation results are consistent with the entire process of previous electric field response signal processing and waveform analysis, accurately eliminates the detection error caused by background interference, and enables the modulation charge difference to truly reflect the actual charge response characteristics of the gas under test. This provides quantitative support for the accurate detection of the gas under test that is consistent with the actual detection process.

[0063] The beneficial effects include: accurately determining the end time of the positive and negative electric fields by combining the changes in the electric field-driven level state with the stabilization time, avoiding time determination deviations caused by fluctuations during the electric field state switching process; performing multi-dimensional morphological analysis on the positive electric field response waveform to fully extract the waveform features corresponding to the gas under test; accurately separating background interference features by identifying interference waveforms through point-by-point numerical comparison; calculating the modulation charge difference by combining logical NOT decision and fixed weight weighted fusion to eliminate interference influence and improve the accuracy of charge value calculation; intuitively obtaining the time parameters of the electric field response by accurately marking the electric field start-up and peak occurrence times and calculating the time difference; and achieving accurate calculation of the modulation charge difference by relying on clear parameter sources and standardized calculation steps, ensuring that the calculation results fully conform to the signal processing and waveform analysis process. The entire process is clear and reproducible, effectively improving the accuracy and reliability of the gas under test signal analysis and feature extraction.

[0064] A5. Based on the fixed distance between the excitation electrode and the collection electrode and the fixed duration of the positive polarity pulse voltage, determine the ion arrival time window of the gas to be tested. When the modulation charge difference exceeds the preset charge threshold, match the time interval with the ion arrival time window. In this embodiment of the invention, determining the ion arrival time window of the gas to be tested based on the fixed distance between the excitation electrode and the collection electrode and the fixed duration of the positive polarity pulse voltage, and matching the time interval with the ion arrival time window when the modulation charge difference exceeds a preset charge threshold, includes: Based on the fixed spacing between the excitation electrode and the collection electrode and the fixed duration of the positive polarity pulse voltage, combined with the ambient temperature and gas pressure parameters in the detection chamber, a standard migration time reference set for various ions in the gas to be tested is generated. Thresholds are defined on the standard migration time reference set to obtain the ion arrival time window of the gas to be measured; The amplitude of the modulation charge difference is monitored in real time. When the amplitude of the modulation charge difference exceeds the preset charge threshold, the time interval is matched with the ion arrival time window.

[0065] First, the distance between the excitation electrode and the collection electrode is fixed to the predetermined spacing after the detection hardware is assembled. Then, the duration of the positive polarity pulse voltage applied between the electrodes is set to a fixed duration preset by the system. The ambient temperature value in the detection chamber is collected in real time by a temperature sensor, and the air pressure value in the detection chamber is collected in real time by a pressure sensor. The fixed spacing, fixed duration, and real-time collected temperature and air pressure parameters are used as the basic conditions for ion migration calculation. The physical properties of different types of ions in the gas to be tested are calculated one by one. The calculation results for each type of ion are uniformly sorted and summarized to form a standard migration time reference set for each type of ion in the gas to be tested.

[0066] Based on the time values ​​corresponding to each type of ion in the gas to be tested in the standard migration time reference set, independent time start boundaries and time end boundaries are defined for each type of ion. The combination of the time start boundaries and time end boundaries corresponding to all ions forms a complete time range interval, which is the ion arrival time window of the gas to be tested.

[0067] The real-time value of the modulated charge difference is continuously read at a fixed time period, and the continuous change of this value is continuously recorded to achieve real-time monitoring of amplitude changes. Each real-time value is directly compared with the charge threshold determined in advance through standard gas calibration experiments. When the real-time value read is greater than the charge threshold, the previously marked and calculated time interval is retrieved, and the value of this time interval is compared with the time range corresponding to each ion within the ion arrival time window to complete the matching operation between the time interval and the ion arrival time window.

[0068] The beneficial effects are as follows: by combining the fixed electrode spacing, fixed pulse voltage duration, and real-time temperature and pressure parameters of the chamber to generate a standard migration time reference set, the reference data can be made to fit the actual detection environment and hardware structure, improving the accuracy of ion migration time determination. By defining independent time boundaries for various ions to form ion arrival time windows, the arrival time periods of different ions can be clearly distinguished, avoiding confusion between different ion signals. By monitoring the amplitude of the modulation charge difference in real time and comparing it with the preset charge threshold, the subsequent matching process can be accurately triggered. Matching the time interval with the ion arrival time window can quickly determine the type of ion to be tested. The entire process is based on actual hardware parameters and environmental data, and the steps are clear and reproducible, effectively improving the reliability and detection efficiency of the identification of gas ions to be tested.

[0069] A6. If the time interval falls within the ion arrival time window, a pyrolysis alarm signal for the gas to be tested will be generated based on the determination that the pyrolysis ions after screening are effective target ions.

[0070] In this embodiment of the invention, if the time interval falls within the ion arrival time window, a pyrolysis alarm signal for the gas to be tested is generated based on the determination result that the pyrolysis ions after screening are valid target ions, including: Based on the matching result between the time interval and the ion arrival time window, the characteristic pulse signal of the target ion in the gas to be tested is obtained; Based on the polarity attribute of the target ion characteristic pulse signal, the corresponding target ion polarity parameter is retrieved from the preset ion polarity feature library; The polarity parameters of the target ion are compared with the charge properties of the screened pyrolysis ions to obtain the ion validity verification signal of the gas to be tested. Based on the ion validity verification signal, a pyrolysis alarm signal for the gas to be tested is generated.

[0071] First, determine the matching result between the time interval and the ion arrival time window. If the time interval falls within the time range corresponding to a certain type of ion, then the ion of that type is determined to be a candidate ion in the gas to be tested. Immediately retrieve the pre-stored characteristic pulse signal of the candidate ion and use the characteristic pulse signal as the target ion characteristic pulse signal of the gas to be tested. If the time interval does not fall within the time range corresponding to any type of ion, then no target ion characteristic pulse signal is generated.

[0072] The polarity of the target ion's characteristic pulse signal is determined by detecting the positive or negative voltage amplitude of the pulse signal. If the pulse signal voltage amplitude is positive, the polarity is determined to be positive; if the pulse signal voltage amplitude is negative, the polarity is determined to be negative. A preset ion polarity feature library stores the polarity parameters corresponding to various ions. These parameters are fixed and stored after being calibrated by standard ion detection experiments. Based on the determined polarity attribute, the ion polarity parameter that completely corresponds to the polarity attribute is searched and retrieved from the ion polarity feature library. This parameter is the target ion polarity parameter.

[0073] The pyrolysis ions generated after the gas to be tested undergoes pyrolysis are screened based on preset pyrolysis ion characteristics determined in advance through standard pyrolysis experiments. These characteristics represent a fixed mass range of pyrolysis ions. Interfering ions outside the mass range are eliminated, and only pyrolysis ions whose mass range conforms to the preset characteristics are retained. The charge properties of the screened pyrolysis ions are extracted, and the charge properties are divided into positive and negative charges. The extracted charge properties are directly compared with the polarity parameters of the target ions. If the charge properties are exactly the same as the polarity parameters of the target ions, they are judged to be consistent, and an ion validity verification signal indicating that the ion is valid is generated. If the charge properties are different from the polarity parameters of the target ions, they are judged to be inconsistent, and an ion validity verification signal indicating that the ion is invalid is generated.

[0074] The ion validity verification signal is identified in real time. If the identified ion validity verification signal indicates that the ion is valid, no alarm signal is generated. If the identified ion validity verification signal indicates that the ion is invalid, the alarm generation mechanism is immediately triggered to generate a pyrolysis alarm signal that can be identified by the detection system in real time. The pyrolysis alarm signal is an electrical signal with a fixed amplitude, the amplitude of which is determined by the alarm threshold calibration of the detection system. It is used to indicate that invalid ions are generated during the pyrolysis of the gas to be tested, and detection and investigation are required.

[0075] The beneficial effects include: accurately acquiring the characteristic pulse signal of the target ion by matching the response time interval with the ion arrival time window, ensuring a one-to-one correspondence between the target signal and the ion to be tested; retrieving the polarity parameter of the target ion based on its polarity attribute to provide a clear and reproducible comparison benchmark for subsequent validity verification; effectively eliminating interfering ions and accurately determining ion validity by screening pyrolysis ions within a fixed mass range and comparing charge attribute consistency; and generating a pyrolysis alarm signal with a fixed amplitude based on the verification signal, which can promptly and accurately indicate detection anomalies. Each step of the entire process has clear operating standards and judgment criteria, and the steps are clear and reproducible, effectively improving the accuracy, reliability, and timeliness of response to anomalies in the detection of the gas to be tested, providing complete verification and alarm support for the accurate detection of the gas to be tested.

[0076] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention.

[0077] This application embodiment can acquire and process relevant data based on artificial intelligence technology. Artificial intelligence is a theory, technology, and application system that uses digital computers or machines controlled by digital computers to simulate, extend, and expand human intelligence, perceive the environment, acquire knowledge, and use that knowledge to obtain optimal results.

[0078] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention.

Claims

1. A technique for pyrolysis of ions, characterized in that, The technology includes: A1. The gas to be tested is introduced into a detection chamber, and a controllable ionization field is generated in the detection chamber based on the excitation electrode and collection electrode placed in the detection chamber. A2. Apply positive and negative pulse voltages alternately to the excitation electrode to generate positive and reverse electric fields alternately in the controllable ionization field. The positive electric field drives the positively charged pyrolysis ions in the gas to be tested toward the collection electrode, and the reverse electric field drives the negatively charged pyrolysis ions in the gas to be tested toward the excitation electrode. The pyrolysis ions of the gas to be tested are then obtained on the collection electrode after screening. A3. Monitor the amount of instantaneous charge accumulated on the collecting electrode, and record the peak value of the positive pulse charge and the valley value of the reverse pulse charge at the end of the positive electric field and the reverse electric field, respectively. A4. Demodulate the difference between the absolute values ​​of the peak value of the positive pulse charge and the valley value of the reverse pulse charge to obtain the modulation charge difference of the gas under test, and measure the time interval from the start of the positive electric field to the occurrence of the peak value of the positive pulse charge. A5. Based on the fixed distance between the excitation electrode and the collection electrode and the fixed duration of the positive polarity pulse voltage, determine the ion arrival time window of the gas to be tested. When the modulation charge difference exceeds the preset charge threshold, match the time interval with the ion arrival time window. A6. If the time interval falls within the ion arrival time window, a pyrolysis alarm signal for the gas to be tested will be generated based on the determination that the pyrolysis ions after screening are effective target ions.

2. The pyrolysis ion technology as described in claim 1, characterized in that, The step of introducing the gas to be tested into a detection chamber and generating a controllable ionization field in the detection chamber based on the excitation electrode and collection electrode placed inside the detection chamber includes: A non-radioactive ionization source is set up in the detection chamber, and the gas to be tested is subjected to gradient thermal dissociation through the non-radioactive ionization source to obtain the pre-ionized gas to be tested. Adjust the geometry of the excitation electrode and the surface potential of the collection electrode in the detection chamber, and construct a uniformly distributed ionization region in the detection chamber according to the gas to be measured after pre-ionization; Based on the electric field intensity distribution characteristics of the ionization region, the power supply frequency of the excitation electrode is dynamically adjusted to generate a controllable ionization field in the detection chamber.

3. The pyrolysis ion technology as described in claim 1, characterized in that, The alternating application of positive and negative polarity pulse voltages to the excitation electrode generates alternating positive and reverse electric fields within a controllable ionization field. The positive electric field drives positively charged pyrolysis ions in the test gas toward the collecting electrode, while the reverse electric field drives negatively charged pyrolysis ions in the test gas toward the excitation electrode. The filtered pyrolysis ions of the test gas are then collected at the collecting electrode. Based on the molecular polarity characteristics of the gas to be tested, a pulse width modulation signal of positive polarity pulse voltage is generated; The pulse width modulation signal is transmitted to the driving circuit of the excitation electrode to control the periodic transition of the surface potential of the excitation electrode, so as to generate a positive electric field of controllable ionization. Under the influence of a positive electric field, the positively charged pyrolysis ions in the gas to be tested are driven away from the excitation electrode by the electrophoretic migration of the positively charged pyrolysis ions in the direction of the collecting electrode, and a positive migration charge is induced on the collecting electrode. When the positive electric field ends, a polarity switching command for generating a negative polarity pulse voltage is generated, reversing the potential difference between the excitation electrode and the collection electrode to construct a reverse electric field for a controllable ionization field. By using a reverse electric field, negatively charged pyrolysis ions in the gas to be tested are bound to the surface of the excitation electrode to form a space charge layer, and the reverse diffusion of negatively charged pyrolysis ions to the collection electrode is blocked, so as to obtain the pyrolysis ions after screening of the gas to be tested.

4. The pyrolysis ion technology as described in claim 3, characterized in that, The process of using the electrophoretic migration of positively charged pyrolysis ions in the gas under a positive electric field to drive the positively charged pyrolysis ions away from the excitation electrode and induce a positive migration charge on the collection electrode includes: Under the influence of a positive electric field, the gas flow rate parameters in the detection chamber are monitored, and the relaxation time of positively charged pyrolysis ions in electrophoretic migration is determined based on the gas flow rate parameters. By performing time-frequency mapping on the relaxation time, the frequency modulation command of the positive polarity pulse voltage is obtained; According to the frequency modulation command, the oscillation frequency of the pulse width modulation signal is adjusted so that the switching frequency and relaxation time of the positive electric field are in the resonance range. By utilizing the electric field force within the resonance range, positively charged pyrolysis ions are driven to undergo directional acceleration, overcoming the fluid resistance generated by the flow of the gas under test. When positively charged pyrolysis ions collide with the surface of the collecting electrode, charge capture occurs on the collecting electrode, resulting in positively transferred charge on the collecting electrode.

5. The pyrolysis ion technology as described in claim 1, characterized in that, The monitoring collects the amount of instantaneous charge accumulated on the electrodes, and records the peak value of the positive pulse charge and the valley value of the reverse pulse charge at the end of the positive and reverse electric fields, respectively, including: The instantaneous current signal output from the collecting electrode is subjected to impedance transformation to obtain the instantaneous voltage signal corresponding to the instantaneous current signal, and the instantaneous voltage signal is subjected to analog-to-digital conversion to obtain the digital sampling sequence of the instantaneous voltage signal; The digital sampling sequence is subjected to sliding window filtering, and the maximum voltage amplitude in the digital sampling sequence is locked at the end of the positive electric field, which is taken as the positive pulse charge peak of the positive electric field. The minimum voltage amplitude in the digital sampling sequence is locked at the end of the reverse electric field, and is used as the reverse pulse charge valley value of the reverse electric field.

6. The pyrolysis ion technology as described in claim 1, characterized in that, The step of demodulating the difference between the absolute values ​​of the peak value of the positive pulse charge and the valley value of the reverse pulse charge to obtain the modulation charge difference of the gas under test, and measuring the time interval from the start of the positive electric field to the occurrence of the peak value of the positive pulse charge, includes: Morphological analysis was performed on the positive electric field response waveform before and after the appearance of the positive pulse charge peak to obtain the positive waveform morphological feature set of the gas under test; The reverse electric field response waveform before and after the appearance of the reverse pulse charge valley is compared with the pre-stored standard interference ion waveform template for pattern recognition to obtain the background interference characteristics of the reverse electric field response waveform. Based on the logical NOT result of the positive waveform morphology feature set and the background interference feature, the absolute values ​​of the positive pulse charge peak and the negative pulse charge valley are weighted and fused to obtain the modulation charge difference of the gas under test. The first timestamp is marked at the moment the positive electric field begins, and the second timestamp is marked at the moment the peak of the positive pulse charge appears; The time difference between the second timestamp and the first timestamp is used as the time interval from the start of the positive electric field to the occurrence of the peak of the positive pulse charge.

7. The pyrolysis ion technology as described in claim 6, characterized in that, The formula for calculating the modulation charge difference is as follows: ； In the formula, To modulate the charge difference, The peak value of the positive pulse charge. The valley value of the reverse pulse charge. The preset morphological-interference coupling coefficient, This refers to the positive morphological scalar factor extracted from the set of positive waveform morphological features. This refers to the interference intensity scalar factor extracted from background interference features. To take the absolute value.

8. The pyrolysis ion technology as described in claim 1, characterized in that, The step of determining the ion arrival time window of the gas to be tested based on the fixed distance between the excitation electrode and the collection electrode and the fixed duration of the positive polarity pulse voltage, and matching the time interval with the ion arrival time window when the modulation charge difference exceeds a preset charge threshold, includes: Based on the fixed spacing between the excitation electrode and the collection electrode and the fixed duration of the positive polarity pulse voltage, combined with the ambient temperature and gas pressure parameters in the detection chamber, a standard migration time reference set for various ions in the gas to be tested is generated. Thresholds are defined on the standard migration time reference set to obtain the ion arrival time window of the gas to be measured; The amplitude of the modulation charge difference is monitored in real time. When the amplitude of the modulation charge difference exceeds the preset charge threshold, the time interval is matched with the ion arrival time window.

9. The pyrolysis ion technology as described in claim 1, characterized in that, If the time interval falls within the ion arrival time window, a pyrolysis alarm signal for the gas to be tested is generated based on the determination result that the pyrolysis ions after screening are valid target ions, including: Based on the matching result between the time interval and the ion arrival time window, the characteristic pulse signal of the target ion in the gas to be tested is obtained; Based on the polarity attribute of the target ion characteristic pulse signal, the corresponding target ion polarity parameter is retrieved from the preset ion polarity feature library; The polarity parameters of the target ion are compared with the charge properties of the screened pyrolysis ions to obtain the ion validity verification signal of the gas to be tested. Based on the ion validity verification signal, a pyrolysis alarm signal for the gas to be tested is generated.

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