Airborne < 210 > Po continuous sampling and monitoring system

Abstract

The invention relates to the technical field of nuclear radiation detection, and particularly discloses an airborne 210Po continuous sampling and monitoring system, which comprises a sampling module, a detection module and a signal processing and analyzing module, and is characterized in that the airborne 210Po continuous sampling and monitoring system comprises a main amplifier connected to a pre-amplifier and used for filtering, forming and further amplifying an amplified signal; the signal acquisition unit is connected to the main amplifier and is used for converting the processed analog signal into a digital signal to form an alpha energy spectrum; the main control unit is connected to the signal acquisition unit and is used for carrying out smoothing processing and peak searching processing on spectrum data of the alpha energy spectrum, discriminating a specific energy spectrum of 210Po according to an energy channel address of a peak, calculating the peak area of the characteristic peak, and calculating the activity concentration of 210Po in the sample by combining the sampling volume recorded by the sampling module and the inherent detection efficiency of the detector; and the data output and display module is connected to the signal processing and analysis module and is used for displaying the alpha energy spectrum and the 210Po activity concentration.

Description

Technical Field

[0001] This invention relates to the field of nuclear radiation detection technology, specifically to an airborne 210Po continuous sampling and monitoring system. Background Technology

[0002] The generation of 210Po nuclides in the atmosphere includes two main sources: natural and artificial. Natural radioactive nuclides 210Po are mainly produced by the decay of radon released from the Earth's surface and are adsorbed by atmospheric particulate matter in a free state to form aerosols. As for artificial sources, 210Po is a characteristic nuclide in lead-bismuth reactors, and airborne emissions are the main way it is released into the environment. Under normal conditions, 210Po is contained in lead-bismuth coolant, and the amount emitted is relatively small. However, due to the high volatility of 210Po, a lead-bismuth leak will result in the release of 210Po. According to a source term assessment of a certain nuclear facility, under normal circumstances, the activity concentration of 210Po discharged into the environment after treatment by the exhaust gas treatment system is above 10 Bq / m3.

[0003] There is relatively little research on rapid sampling and monitoring of 210Po. Existing monitoring methods measure the activity concentration of 210Po in the atmosphere by sampling and analyzing in the laboratory. This method has high accuracy, but it cannot achieve continuous sampling and monitoring, has low work efficiency, and cannot provide early warning of coolant leaks and excessive emissions. Furthermore, although 210Po is a pure alpha decay product, it is also a radon decay product (RaF), so the interference of radon and its decay products needs to be removed before monitoring and sampling. To address this, we propose an airborne 210Po continuous sampling and monitoring system. Summary of the Invention

[0004] The purpose of this invention is to provide an airborne 210Po continuous sampling and monitoring system to solve the problems mentioned in the background art that existing monitoring methods cannot achieve continuous sampling and monitoring, cannot provide early warning of coolant leakage and excessive emissions, and require the removal of radon and its decay products before monitoring and sampling.

[0005] To achieve the above objectives, the present invention provides the following technical solution: a gaseous 210Po continuous sampling and monitoring system, comprising a sampling module, which includes: a particle size filter, disposed at the gas inlet, for filtering artificial radionuclides uranium, plutonium, and natural background particles. 210 Po's large-diameter particles; a large-volume sealed stainless steel chamber connected to a particle size filter for continuously collecting gas samples via differential pressure displacement and providing a space for static decay of the collected samples; a chamber pressurization device for applying positive high pressure to the surface of the stainless steel chamber, using electrostatic accumulation to reduce the concentration of particulate matter in the gas sample. 210Po is collected onto the detector surface; the detection module includes: an ion-implanted silicon (PIPS) semiconductor detector, housed within a stainless steel cavity, for collecting... 210 The alpha particles emitted by Po generate a weak current signal through ionization; a preamplifier, connected to the PIPS semiconductor detector, is used to amplify the weak current signal; a bias voltage circuit is used to provide the operating voltage for the preamplifier; a signal processing and analysis module includes: a main amplifier, connected to the preamplifier, used to filter and shape the amplified signal and further amplify it; a signal acquisition unit, connected to the main amplifier, used to convert the processed analog signal into a digital signal to form an alpha spectrum; a main control unit, connected to the signal acquisition unit, used to smooth and peak-find the alpha spectrum data, identify the specific energy spectrum of 210Po based on the energy channel address of the peak, calculate the peak area of ​​the characteristic peak, and calculate the energy of the sample by combining the sampling volume recorded by the sampling module and the inherent detection efficiency of the detector. 210 The activity concentration of Po; a data output and display module, connected to the signal processing and analysis module, for displaying the α energy spectrum and... 210 Po activity concentration.

[0006] In this system, after differential pressure replacement sampling is completed, the gas sample is allowed to remain in the large-volume sealed stainless steel cavity for a predetermined period of time to allow the short-lived radon progeny 218Po and 214Po to decay, thereby reducing their impact on... 210 Interference in Po measurement.

[0007] The positive high voltage applied by the cavity pressurization device is coordinated with the positioning of the PIPS semiconductor detector, thereby enabling... 210 Po is collected directly onto the detector surface, so that the energy of the alpha particles is not lost in the air range.

[0008] The main control module uses a five-point smoothing method with polynomial fitting shift to smooth the α-energy spectrum data. The specific smoothing formula is as follows:

[0009]

[0010] Where i is the channel number ordinal number, yi is the count of the i-th channel in the smoothed spectrum, and yi-2, yi-1, yi, yi+1, and yi+2 are the counts of the corresponding channels on the measured spectrum.

[0011] When the main control module performs peak finding processing on the α energy spectrum data, it uses a simple comparison method, which includes the following steps:

[0012] S1: First, perform a coarse selection. The criterion for determining whether there may be a peak near a certain channel is:

[0013] C(n)-B1>2|C(nW)-B1|;

[0014] C(n)-B r >2|C(n+W)-B r |;

[0015] C(n)≥C(n+1);

[0016] C(n)≥C(n-1);

[0017] Where FWHM is the number of channels corresponding to the full width of the channel at the half-peak maximum value, and W is the FWHM quantity expressed in channels, with a value of (E represents energy). For a stable and normal detector, parameters a and b are input based on the detector's inherent data. B1 and Br are respectively:

[0018]

[0019] The nth peak that meets the above conditions is considered to be possible.

[0020] S2: Determine the peak center; First, find the peak apex, searching within a smaller range of 1 W channels. Find the channel with the largest count as the peak apex. Then, within a range of 1 W channels to the left and right of the peak apex, find the peak center using the count as the weight based on the weighted average method.

[0021]

[0022] S3: Determine the basic Gaussian shape of the peak using the net counts of channels W / 2 and W / 3 to the left and right of the peak center:

[0023]

[0024] Among them, C LAVE This represents the average net count of the three channels on the left, C LAVE01 It is the net count of the left W / 2 channel;

[0025]

[0026] Among them, C LAVE21 This represents the net count for the left W / 3 channel;

[0027] This leads to the following criteria for determining the basic Gaussian shape of a peak:

[0028] C AVE0 >0.6×(C LAVE +C RAVE )

[0029] C AVE0 >GA×C LAVE1

[0030] C AVE0 >GA×C RAVE1

[0031] (C(MW)+C(M+W)) / 2>GA×(C RAVE1 +C LAVE1 ) / 4

[0032] Among them, C AVE0 For counting at the peak center, C LAVE and C RAVE For the average net count of left and right W / 2 channels, C LAVE1 and C RAVE1 The net count for single points on the left and right lanes is given, and GA is a constant.

[0033] S4: Detailed judgment of peak shape: Based on the parameters defined in the above formulas, 10 criteria for detailed judgment of peak shape are given:

[0034] C LAVE01 >0 C RAVE01 >0

[0035] C LAVE21 >0 C RAVE21 >0

[0036] C LAVE01 >1.5×C LAVE1 C RAVE01 >1.5×C RAVE1

[0037] C LAVE21 >2×C LAVE1 C RAVE21 >2×C RAVE1

[0038] C LAVE21 >C LAVE0 C RAVE21 >C RAVE01

[0039] If at least eight of the above criteria are met, it is determined to be a true peak. Based on the energy channel address of the true peak, it is then identified. 210 The characteristic peak of Po.

[0040] When calculating the peak area, the main control module uses the all-energy peak area method, subtracting the background along a linear trend. The specific steps are as follows:

[0041] S41: First determine the left and right boundary channels of the peak. Let the left and right boundary channels of the peak be L and R respectively. Then the number of channels occupied by the all-energy peak is R-L+1.

[0042] S42: Add the counts yi of each channel within the peak to obtain the area A under the curve bounded by L and R.

[0043] S43: Subtract the trapezoidal base B, that is:

[0044]

[0045] S44: The net area of ​​the full-energy peak is:

[0046]

[0047] Among them, the main control unit calculates 210 By analyzing the full peak area of ​​the characteristic α energy spectrum of Po and combining it with the known sample volume, the concentration of [something] in the air can be quantitatively determined. 210 Po content.

[0048] The present invention has at least the following beneficial effects: its continuous sampling monitoring system enables the monitoring of airborne particles... 210 The automated and continuous monitoring of radon overcomes the problem of low efficiency in traditional analysis. The air to be tested first undergoes particle size filtration to remove large-diameter interfering particles; then it enters a large-volume sampling chamber, where the short-lived radon progeny decay naturally through settling, significantly reducing natural background interference; finally, high-voltage electrostatic accumulation technology is used to collect the target nuclide. 210 Po is directly adsorbed onto the surface of the semiconductor detector for measurement and energy spectrum analysis; finally, the system automatically processes the energy spectrum data through intelligent algorithms and identifies... 210 By analyzing the characteristic peaks of Po and calculating their activity concentrations, this invention achieves full automation from sampling to result output, greatly improving monitoring efficiency. Through physical filtration and static decay, it effectively eliminates interference from other artificial nuclides and natural radon progeny, ensuring the accuracy and specificity of the measurement results. The system can provide near real-time monitoring data, providing strong technical support for environmental radiation safety early warning and emergency response. Attached Figure Description

[0049] Figure 1 This is a flowchart of the continuous sampling and monitoring process of the present invention;

[0050] Figure 2 This is a diagram of the particle size filtration and differential pressure replacement sampling structure.

[0051] Figure 3 This is a schematic diagram of the total peak area;

[0052] Figure 4 The image shows the α-energy spectral line of a sample from a specific embodiment. Detailed Implementation

[0053] 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.

[0054] Please see Figure 1-4 The present invention provides a technical solution: an airborne... 2 A 10Po continuous sampling and monitoring system includes a sampling module comprising: a particle size filter, located at the gas inlet, for filtering artificial radionuclides uranium, plutonium, and natural background particles. 210 Po's large-diameter particles; a large-volume sealed stainless steel chamber connected to a particle size filter for continuously collecting gas samples via differential pressure displacement and providing a space for static decay of the collected samples; a chamber pressurization device for applying positive high pressure to the surface of the stainless steel chamber, using electrostatic accumulation to reduce the concentration of particulate matter in the gas sample. 210 Po is collected onto the detector surface; the detection module includes: an ion-implanted silicon (PIPS) semiconductor detector, housed within a stainless steel cavity, for collecting... 210 The alpha particles emitted by Po generate a weak current signal through ionization; a preamplifier, connected to the PIPS semiconductor detector, amplifies the weak current signal; a bias voltage circuit provides the operating voltage for the preamplifier; a signal processing and analysis module includes: a main amplifier, connected to the preamplifier, for filtering, shaping, and further amplifying the amplified signal; a signal acquisition unit, connected to the main amplifier, for converting the processed analog signal into a digital signal to form an alpha spectrum; and a main control unit, connected to the signal acquisition unit, for smoothing and peak-finding the alpha spectrum data, and identifying the peaks based on their energy addresses. 210 The specific energy spectrum of Po is calculated, and the peak area of ​​the characteristic peak is calculated. Combined with the sampling volume recorded by the sampling module and the inherent detection efficiency of the detector, the concentration of the sample is calculated. 210 The activity concentration of Po; a data output and display module, connected to the signal processing and analysis module, for displaying the α energy spectrum and... 210 Po activity concentration.

[0055] After differential pressure replacement sampling is completed, the gas sample is allowed to stand in the large-volume sealed stainless steel cavity for a predetermined period of time to allow the short-lived radon progeny 218Po and 214Po to decay, thereby reducing their impact on... 210 Interference in Po measurement.

[0056] The positive high voltage applied by the cavity pressurization device is coordinated with the positioning of the PIPS semiconductor detector, so that...210 Po is collected directly onto the detector surface, so that the energy of the alpha particles is not lost in the air range.

[0057] When the main control module smooths the alpha energy spectrum data, it uses a five-point smoothing method with polynomial fitting shift. The specific smoothing formula is as follows:

[0058]

[0059] Where i is the channel number ordinal number, yi is the count of the i-th channel in the smoothed spectrum, and yi-2, yi-1, yi, yi+1, and yi+2 are the counts of the corresponding channels on the measured spectrum.

[0060] When the main control module performs peak finding processing on the α energy spectrum data, it uses a simple comparison method, which includes the following steps:

[0061] S1: First, perform a coarse selection. The criterion for determining whether there may be a peak near a certain channel is:

[0062] C(n)-B1>2|C(nW)-B1|;

[0063] C(n)-B r >2|C(n+W)-B r |;

[0064] C(n)≥C(n+1);

[0065] C(n)≥C(n-1);

[0066] Where FWHM is the number of channels corresponding to the full width of the channel at the half-peak maximum value, and W is the FWHM quantity expressed in channels, with a value of (E represents energy). For a stable and normal detector, parameters a and b are input based on the detector's inherent data. B1 and Br are respectively:

[0067]

[0068] The nth peak that meets the above conditions is considered to be possible.

[0069] S2: Determine the peak center; First, find the peak apex, searching within a smaller range of 1 W channels. Find the channel with the largest count as the peak apex. Then, within a range of 1 W channels to the left and right of the peak apex, find the peak center using the count as the weight based on the weighted average method.

[0070]

[0071] S3: Determine the basic Gaussian shape of the peak using the net counts of channels W / 2 and W / 3 to the left and right of the peak center:

[0072]

[0073] Among them, C LAVE This represents the average net count of the three channels on the left, C LAVE01 It is the net count of the left W / 2 channel;

[0074]

[0075] Among them, C LAVE21 This represents the net count for the left W / 3 channel;

[0076] This leads to the following criteria for determining the basic Gaussian shape of a peak:

[0077] C AVE0 >0.6×(C LAVE +C RAVE )

[0078] C AVE0 >GA×C LAVE1

[0079] C AVE0 >GA×C RAVE1

[0080] (C(MW)+C(M+W)) / 2>GA×(C RAVE1 +C LAVE1 ) / 4

[0081] Among them, C AVE0 For counting at the peak center, C LAVE and C RAVE For the average net count of left and right W / 2 channels, C LAVE1 and C RAVE1 The net count for single points on the left and right lanes is given, and GA is a constant.

[0082] S4: Detailed judgment of peak shape: Based on the parameters defined in the above formulas, 10 criteria for detailed judgment of peak shape are given:

[0083] C LAVE01 >0 C RAVE01 >0

[0084] C LAVE21 >0 C RAVE21 >0

[0085] C LAVE01 >1.5×C LAVE1 C RAVE01 >1.5×C RAVE1

[0086] C LAVE21 >2×C LAVE1 CRAVE21 >2×C RAVE1

[0087] C LAVE21 >C LAVE0 C RAVE21 >C RAVE01

[0088] If at least eight of the above criteria are met, it is determined to be a true peak. Based on the energy channel address of the true peak, it is then identified. 210 The characteristic peak of Po.

[0089] When calculating the peak area, the main control module uses the all-energy peak area method, subtracting the background along a linear trend. The specific steps are as follows:

[0090] S41: First determine the left and right boundary channels of the peak. Let the left and right boundary channels of the peak be L and R respectively. Then the number of channels occupied by the all-energy peak is R-L+1.

[0091] S42: Add the counts yi of each channel within the peak to obtain the area A under the curve bounded by L and R.

[0092] S43: Subtract the trapezoidal base B, that is:

[0093]

[0094] S44: The net area of ​​the full-energy peak is:

[0095]

[0096] The main control unit calculates... 210 By analyzing the full peak area of ​​the characteristic α energy spectrum of Po and combining it with the known sample volume, the concentration of [something] in the air can be quantitatively determined. 210 Po content.

[0097] A specific example of the present invention is as follows:

[0098] Step 1: Use known energy nuclides to calibrate the energy spectrum measurement system to obtain the channel address of the α energy spectrum peak of different nuclides, and establish the relationship curve between α particle energy and channel address: E(i)=Gi+E0, where i is the channel number of the peak position, E(i) is the energy of the corresponding i-th channel α ray, G is the slope of the straight line, and E0 is the intercept.

[0099] use 210 Po standard samples are obtained through the formula: Calculate 210 The calibration coefficient k(Bqs) of the Poα ray peak, where: A is the activity of the standard sample (Bq), S is the area of ​​the full-energy peak, and S0 is the background count rate (counts / s).

[0100] Step 2: Close the gas inlet valve of the stainless steel sealed chamber, open the evacuation valve, start the rear vacuum pump, evacuate the stainless steel gas to a vacuum, determine the vacuum level using a differential pressure gauge, close the sampling pump and evacuation valve, and open the gas inlet valve. 210 The gas to be tested, Po, enters the stainless steel chamber through a particle size filter under the action of pressure difference.

[0101] Step 3: Close the gas inlet valve and allow the gas to be tested in the stainless steel chamber to stand for a period of time, allowing the short-lived radon progeny 218Po and 214Po to decay, thereby reducing their impact on the test gas. 210 Interference in Po measurement.

[0102] Step 4: After a period of settling, apply a positive high voltage to the stainless steel cavity to collect the static electricity. 210 Po adsorbs onto the detector surface, and the characteristic alpha particles deplete energy and generate analog signals in the gold-silicon surface barrier semiconductor detector.

[0103] Step 5: Run the α spectrometer system to smooth and peak-find the detected α energy spectrum. Based on the energy channel address of the true peak and referring to the element characteristic energy table, identify the... 210 The characteristic peak of Po.

[0104] Step Six: Determine the left and right boundary channels L and R of the peak. The number of channels occupied by the all-energy peak is then R-L+1. Add the channel counts yi within the peak, and use the total peak area method (TPA) to obtain the area under the curve with L and R as boundaries. Subtract the trapezoidal background to obtain the net area of ​​the all-energy peak:

[0105]

[0106] Where A is the total count within the peak region and B is the trapezoidal background.

[0107] Step 7, Combining 210 The Po energy scale factor k is obtained using the formula: Calculate the sample to be tested 210 The activity concentration of Poα (Bq / m3), where V is the sampling volume (m3).

[0108] Assuming the spectrometer system used is 210 The energy calibration factor k of the Po standard sample is 1.5. After inputting into the α-spectrum system and passing through particle size filter, 1 L (0.1 m) of radioactive sample is taken. 3 After static decay, a positive high voltage is applied to collect the electrostatic accumulation. 210 Po, the α signal of the sample under test is amplified, converted, and processed by energy dispersive spectroscopy to obtain 210 The energy spectrum curve of Poα rays is as follows: Figure 4 .

[0109] After subtracting the background count, the total peak area is 150 Bq / s. 210 The activity concentration of Poα radiation particles is:

[0110] It should be noted that, in this document, relational terms such as "first" and "second" are used only 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 process, method, article, or apparatus.

[0111] 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 gasborne 210Po continuous sampling monitoring system characterized by, include: The sampling module includes: The particle size filter is installed at the gas inlet to filter artificial radionuclides uranium and plutonium, as well as large-diameter particles containing 210Po in the natural background. A large-volume sealed stainless steel cavity is connected to the particle size filter device for continuously collecting the gas sample to be tested by differential pressure replacement and providing a static decay space for the collected sample. A chamber pressurization device is used to apply a positive high voltage to the surface of the stainless steel chamber, so that 210Po in the gas sample is collected to the detector surface through electrostatic accumulation. The detection module includes: An ion-implanted silicon (PIPS) semiconductor detector is disposed in the stainless steel cavity to collect alpha particles emitted by 210Po and generate a weak current signal through ionization. A preamplifier, connected to the PIPS semiconductor detector, is used to amplify the weak current signal at the primary stage. A bias voltage circuit is used to provide operating voltage for the preamplifier; The signal processing and analysis module includes: The main amplifier, connected to the preamplifier, is used to filter, shape, and further amplify the amplified signal. A signal acquisition unit, connected to the main amplifier, is used to convert the processed analog signal into a digital signal to form an α energy spectrum. The main control unit, connected to the signal acquisition unit, is used to smooth and peak-finding the spectral data of the α energy spectrum, identify the specific energy spectrum of 210Po based on the energy channel address of the peak, calculate the peak area of ​​the characteristic peak, and calculate the activity concentration of 210Po in the sample by combining the sampling volume recorded by the sampling module and the inherent detection efficiency of the detector. The data output and display module is connected to the signal processing and analysis module and is used to display the α energy spectrum and 210Po activity concentration.

2. A gasborne 210Po continuous sampling monitor system according to claim 1, characterised in that: After differential pressure replacement sampling is completed, the gas sample is allowed to stand in the large-volume sealed stainless steel cavity for a predetermined period of time to allow the short-lived radon progeny 218Po and 214Po to decay, thereby reducing their interference with the 210Po measurement.

3. A continuous sampling airborne 210Po monitoring system according to claim 1, wherein: The positive high pressure applied by the cavity pressurization device, in conjunction with the positioning of the PIPS semiconductor detector, allows 210Po to be directly collected onto the detector surface, thus ensuring that the energy of the alpha particles is not substantially lost in the air range.

4. A gasborne 210Po continuous sampling monitor system according to claim 1, wherein: When the main control module smooths the α-energy spectrum data, it uses a five-point smoothing method with polynomial fitting shift. The specific smoothing formula is as follows: Where i is the channel number ordinal number, yi is the count of the i-th channel in the smoothed spectrum, and yi-2, yi-1, yi, yi+1, and yi+2 are the counts of the corresponding channels on the measured spectrum.

5. A continuous sampling airborne 210Po monitoring system according to claim 1, wherein: When the main control module performs peak finding processing on the α energy spectrum data, it uses a simple comparison method to find the peaks, including the following steps: S1: First, perform a coarse selection. The criterion for determining whether there may be a peak near a certain channel is: C(n)-B1>2|C(nW)-B1|; C(n)-B r C(n+W)-B r | C(n)≥C(n+1); C(n)≥C(n-1); where FWHM is the full width of the channel corresponding to the half maximum of the peak, and W is the FWHM expressed in channels, which takes the value (E is energy), for a stable normal detector, the parameters a, b are input according to the intrinsic data of the detector, B1, Br are respectively: The nth peak that meets the above conditions is considered to be possible. S2: Determine the peak center; first find the peak vertex, find it in a smaller 1 W channel range, find the maximum channel of the count as the peak vertex, and then find the peak center in the 1 W channel range left and right of the peak vertex according to the weight average method with the count as the weight: S3: Judge the basic Gaussian shape of the peak, and use the net count of W / 2 channels and W / 3 channels left and right of the peak center to judge: where C LAVE represents the left 3-channel average net count, C LAVE01 is the left W / 2-channel net count; where C LAVE21 represents the left W / 3 net count; Thus, the following criteria for judging the basic Gaussian shape of the peak are generated: C AVE0 >0.6×(C LAVE +C RAVE ) C AVE0 >GA×C LAVE1 C AVE0 >GA×C RAVE1 (C(M-W) + C(M+W)) / 2 > GA x (C RAVE1 + C LAVE1 ) / 4 where C AVE0 is the peak center count, C LAVE and C RAVE are the left and right W / 2 channel average net counts, and C LAVE1 and C RAVE1 are the left and right channel single point net counts, and GA is a constant; S4: Detailed judgment of peak shape: 10 criteria for detailed judgment of peak shape are given by the parameters defined in the above formula: C LAVE01 >0 C LAVE01 >0 C LAVE21 >0 C RAVE21 >0 C LAVE01 >1.5×C LAVE1 C RAVE01 >1.5×C RAVE1 C LAVE21 >2×C LAVE1 C RAVE21 >2×C RAVE1 C LAVE21 >C LAVE0 C RAVE21 >C RAVE01 If the above at least 8 criteria are satisfied, it is determined as a true peak, and according to the energy channel address of the true peak, the characteristic peak of Po is identified 210 Po.

6. A continuous sampling airborne 210Po monitoring system according to claim 1, wherein: When the main control module calculates the peak area, the total peak area method is adopted, and the background is deducted according to the trend of the straight line, and the specific steps are as follows: S41: First determine the left and right boundary channels of the peak, and set the left and right channels of the peak as L and R respectively, then the channel number occupied by the total peak is R-L+1; S42: Add the counts yi in each lane within the peak, i.e. obtain the area A under the side of the curve bounded by L and R: S43: Subtract the trapezoidal background B, that is: S44: The net area of the total peak is:

7. A continuous sampling airborne 210Po monitoring system according to claim 1, wherein: The main control unit quantitatively determines the content of 210Po in the air by calculating the total peak area of the 210Po characteristic alpha spectrum and combining the known sampling volume.

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