A monitoring system and method for the concentration of pollen biological aerosol

Abstract

The present invention discloses a pollen biological aerosol concentration monitoring system and a monitoring method, which relate to the technical field of pollen biological aerosol concentration detection. The monitoring system includes: a power unit, a light source, a detector, a measurement chamber, and a data processing unit; the power unit is used to output negative pressure power to enable the air in the measured environment to enter the measurement chamber, so as to obtain the air to be measured; the air to be measured contains pollen particles; the light source is used to provide incident light for the air to be measured; the detector is used to receive the elastic scattering field strength signal and the fluorescence scattering field strength signal generated after the incident light irradiates the air to be measured, and convert the elastic scattering field strength signal into a first time-domain electrical pulse signal, and convert the fluorescence scattering field strength signal into a second time-domain electrical pulse signal; the data processing unit is electrically connected to the detector; the data processing unit is used to determine the number of pollen particles in the air to be measured according to the first time-domain electrical pulse signal and the second time-domain electrical pulse signal. The present invention can improve the accuracy and real-time performance of detection.

Description

Technical Field

[0001] The present invention relates to the technical field of pollen biological aerosol concentration detection, and particularly relates to a pollen biological aerosol concentration monitoring system and a monitoring method. Background Art

[0002] Traditional pollen monitoring methods mainly rely on manual sampling and microscopic analysis, which are time-consuming and laborious, and have poor real-time performance. Light scattering and fluorescence induction technologies provide an efficient and rapid method for monitoring the concentration of pollen biological aerosols, which can further improve the accuracy and real-time performance of detection. Summary of the Invention

[0003] The purpose of the present invention is to provide a pollen biological aerosol concentration monitoring system and a monitoring method, which can improve the accuracy and real-time performance of detection.

[0004] To achieve the above purpose, the present invention provides the following solutions:

[0005] A pollen biological aerosol concentration monitoring system, the monitoring system includes: a power unit, a light source, a detector, a measurement chamber, and a data processing unit;

[0006] The power unit is used to output negative pressure power to make the air in the measured environment enter the measurement chamber to obtain the air to be measured; the air to be measured contains pollen particles;

[0007] The light source is used to provide incident light for the air to be measured;

[0008] The detector is used to receive the elastic scattering field strength signal and the fluorescence scattering field strength signal generated after the incident light irradiates the air to be measured, and convert the elastic scattering field strength signal into a first time-domain electrical pulse signal, and convert the fluorescence scattering field strength signal into a second time-domain electrical pulse signal;

[0009] The data processing unit is electrically connected to the detector; the data processing unit is used to determine the number of pollen particles in the air to be measured according to the first time-domain electrical pulse signal and the second time-domain electrical pulse signal.

[0010] Optionally, the measurement chamber includes an inlet, an outlet, a light source irradiation window, and a spectral detection window;

[0011] The air to be measured enters the measurement chamber from the inlet;

[0012] The light source provides incident light for the air to be measured from the light source irradiation window;

[0013] The above detector receives the elastic scattering field strength signal and the fluorescence scattering field strength signal generated after the above incident light irradiates the pollen particles in the above air to be measured through the above spectral detection window;

[0014] The above air to be measured after being detected by the above detector exits the above measurement cavity from the above outlet.

[0015] Optionally, the above incident light is a laser.

[0016] Optionally, it further includes a host computer;

[0017] The above host computer is connected to the above data processing unit;

[0018] The above host computer is used to display the number of pollen particles in the above air to be measured at each moment within a first preset time period.

[0019] A method for monitoring the concentration of pollen biological aerosol, which is applied to the above pollen biological aerosol concentration monitoring system, and the method includes:

[0020] In response to a pollen biological aerosol concentration monitoring request, obtaining the time-domain electrical pulse signals of the elastic scattering field strength signal and the fluorescence scattering field strength signal generated after the air to be measured is irradiated by a light source;

[0021] Extracting the characteristics of the time-domain electrical pulse signal of the above elastic scattering field strength signal to obtain an elastic scattering characteristic signal;

[0022] According to the above elastic scattering characteristic signal, extracting the characteristics of the time-domain electrical pulse signal of the above fluorescence scattering field strength signal to obtain a fluorescence scattering characteristic signal;

[0023] According to the physical characteristics of pollen particles and the above fluorescence scattering characteristic signal, determining the total area of pollen particles in the above air to be measured;

[0024] According to a preset area threshold of a single pollen particle and the total area of pollen particles in the above air to be measured, determining the number of pollen particles in the above air to be measured.

[0025] Optionally, the above determining the total area of pollen particles in the above air to be measured according to the physical characteristics of pollen particles and the above fluorescence scattering characteristic signal includes:

[0026] According to the physical characteristics of pollen particles, determining the width threshold and amplitude threshold of the fluorescence scattering characteristic signal of the above pollen particles;

[0027] Determining a characteristic interval greater than the width threshold and amplitude threshold from the above fluorescence scattering characteristic signal;

[0028] Applying the integration method to calculate the area of the above characteristic interval to obtain the total area of pollen particles in the above air to be measured.

[0029] Optionally, before performing the step of "extracting the characteristics of the time-domain electrical pulse signal of the above elastic scattering field strength signal to obtain an elastic scattering characteristic signal", the above method further includes:

[0030] Performing a noise removal operation on the time-domain electrical pulse signals of the above elastic scattering field strength signal and the above fluorescence scattering field strength signal to obtain the time-domain electrical pulse signal of the above elastic scattering field strength signal after denoising and the time-domain electrical pulse signal of the above fluorescence scattering field strength signal after denoising.

[0031] Optionally, performing a noise removal operation on the time-domain electrical pulse signals of the above elastic scattering field strength signal and the above fluorescence scattering field strength signal to obtain the time-domain electrical pulse signal of the above elastic scattering field strength signal after denoising and the time-domain electrical pulse signal of the above fluorescence scattering field strength signal after denoising includes:

[0032] Removing the noise of the time-domain electrical pulse signal of the above elastic scattering field strength signal to obtain a first denoised pulse signal;

[0033] Removing the noise of the time-domain electrical pulse signal of the above fluorescence scattering field strength signal to obtain a second denoised pulse signal;

[0034] Obtaining the device noise of the above pollen biological aerosol concentration monitoring system;

[0035] Removing the above device noise from the above first denoised pulse signal to obtain the time-domain electrical pulse signal of the above elastic scattering field strength signal after denoising;

[0036] Removing the above device noise from the above second denoised pulse signal to obtain the time-domain electrical pulse signal of the above fluorescence scattering field strength signal after denoising.

[0037] Optionally, the above method further includes:

[0038] Calculating the volume of the above air to be measured within a second preset time period according to the gas flow rate of the power unit;

[0039] Calculating the pollen biological aerosol concentration of the above air to be measured according to the number of pollen particles in the above air to be measured and the above volume.

[0040] Optionally, plotting the pollen biological aerosol concentration at each moment within a first preset time period of the above air to be measured according to the pollen biological aerosol concentration of the above air to be measured.

[0041] According to the specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0042] The present invention discloses a monitoring system and a monitoring method for the concentration of pollen biological aerosol. A power unit outputs a negative pressure power to enable the air in the measured environment to enter the measurement chamber to obtain the air to be measured; wherein, the air to be measured contains pollen particles. A light source is used to provide incident light for the air to be measured. A detector receives the elastic scattering field strength signal and the fluorescence scattering field strength signal generated after the incident light irradiates the air to be measured, converts the elastic scattering field strength signal into a first time-domain electrical pulse signal, and converts the fluorescence scattering field strength signal into a second time-domain electrical pulse signal. A data processing unit determines the number of pollen particles in the air to be measured according to the first time-domain electrical pulse signal and the second time-domain electrical pulse signal. By utilizing the physical characteristics of pollen particles and collecting the elastic scattering field strength signal and the fluorescence scattering field strength signal of pollen particles, the present invention calculates the number of pollen particles, thereby improving the accuracy and real-time performance of detection. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for use in the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention, and those of ordinary skill in the art can also obtain other drawings based on these drawings without creative efforts.

[0044] Figure 1 It is a schematic plan view of a monitoring system for the concentration of pollen biological aerosol provided by an embodiment of the present invention;

[0045] Figure 2 It is a flow chart for collecting elastic light scattering and laser-induced fluorescence signals;

[0046] Figure 3 It is a schematic diagram of the principle of laser-induced fluorescence;

[0047] Figure 4 It is a schematic flow chart of a method for monitoring the concentration of pollen biological aerosol;

[0048] Figure 5 It is a flow chart of a method for monitoring the concentration of pollen biological aerosol provided by another embodiment;

[0049] Figure 6 It is a flow chart for signal preprocessing;

[0050] Figure 7 It is a flow chart for data monitoring and analysis;

[0051] Figure 8 It is a signal diagram of a kind of pollen collected;

[0052] Figure 9 It is a signal diagram of another kind of pollen collected.

[0053] Symbol Explanation:

[0054] Measurement chamber — 1, spectral detection window — 2, light source irradiation window — 3, pollen particle — 4. Specific Embodiment

[0055] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts shall fall within the protection scope of the present invention.

[0056] The object of the present invention is to provide a pollen biological aerosol concentration monitoring system and a monitoring method, aiming to improve the accuracy and real-time performance of detection.

[0057] To make the above objects, features, and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0058] Embodiment 1

[0059] As Figure 1 shown, a pollen biological aerosol concentration monitoring system in this embodiment includes: a power unit, a light source, a detector, a measurement chamber 1, and a data processing unit.

[0060] The power unit is used to output negative pressure power to make the air in the measured environment enter the measurement chamber 1 to obtain the air to be measured; the air to be measured contains pollen particles 4.

[0061] The light source is used to provide incident light for the air to be measured.

[0062] The detector is used to receive the elastic scattering field strength signal and the fluorescence scattering field strength signal generated after the incident light irradiates the air to be measured, and convert the elastic scattering field strength signal into a first time-domain electrical pulse signal, and convert the fluorescence scattering field strength signal into a second time-domain electrical pulse signal.

[0063] The data processing unit is electrically connected to the detector; the data processing unit is used to determine the number of pollen particles 4 in the air to be measured according to the first time-domain electrical pulse signal and the second time-domain electrical pulse signal.

[0064] In practical applications, as Figure 2 shown, under the action of an air pump, particles in the environment pass through the photosensitive area one by one. After colliding with the incident light, corresponding elastic scattering light and induced fluorescence scattering light will be generated. These signals represent the physical parameters and biological activities of the particles. Whether the measured particles are pollen can be calculated through these signals.

[0065] Among them, the measurement chamber 1 includes an inlet, an outlet, a light source irradiation window 3 and a spectral detection window 2; the air to be measured enters the measurement chamber 1 from the inlet; the light source provides incident light for the air to be measured from the light source irradiation window 3; the detector receives, from the spectral detection window 2, the elastic scattering field strength signal and the fluorescence scattering field strength signal generated after the incident light irradiates the pollen particles 4 in the air to be measured; the air to be measured after being detected by the detector leaves the measurement chamber 1 from the outlet.

[0066] Optionally, the incident light is a laser.

[0067] In addition, it further includes a host computer; the host computer is connected to the data processing unit; the host computer is used to display the number of pollen particles 4 in the air to be measured at each moment within a first preset time period.

[0068] As Figure 3 shown, pollen is active and is a kind of bioaerosol. The particle contains organic molecules characterizing biological activity such as phenylalanine, tyrosine, tryptophan, nicotinamide adenine dinucleotide (NADH), and riboflavin. Under the induction of laser light, it will generate intrinsic fluorescence. The method of using the intrinsic fluorescence characteristic to distinguish the biological attributes of biological particles such as pollen and bacteria is called laser-induced intrinsic fluorescence detection method. Most non-biological particles can be distinguished from the characteristic of whether they can excite intrinsic fluorescence, and a preliminary classification of biological particles such as pollen and bacteria and non-biological particles is carried out. Endogenous fluorescence is also called autofluorescence, which is a kind of photoluminescence phenomenon existing in substances themselves, that is, when a certain substance is excited by an electromagnetic wave incident field and enters a high-energy state, and then returns to the ground state within a very short time and emits emission light with a longer wavelength than the incident field.

[0069] In practical applications, the particles in the measured environment, under the action of the air flow power source, enter the measurement chamber 1 in the form of a continuous air flow carrying monodisperse particles. The measured particles pass through the measurement light area formed by the overlap of the measurement spot and the sample flow one by one, and simultaneously generate elastic scattering light that can characterize the particle size parameters of the measured single particle and endogenous fluorescence that characterizes the content of fluorescent substances in the measured particles. The photodetector and the analysis and identification algorithm are used to acquire and analyze the optical signal information and judge the characteristics of the measured particles in real time, identify the pollen particles 4 and other particles, and retain the measured pollen data.

[0070] The air pump serves as a power unit, and the power unit serves as the power source of the pollen bioaerosol concentration monitoring system, providing a stable negative pressure power for the pollen bioaerosol concentration monitoring system to collect samples, so that the particles in the measured environment can continuously pass through the photosensitive area; the light source can provide a stable incident electromagnetic field for the spectral measurement of pollen. When the incident photons collide with the pollen particles entrained in the sample airflow, corresponding elastic scattering fields and fluorescence scattering fields are generated; at this time, these field intensity signals representing the physical parameters and biological activity of the measured particles are collected and received by the photoelectric detector, and enter the data processing unit in the form of time-domain electrical pulse signals; the data processing unit extracts and processes the useful information in the continuous pulse signal; finally, these data representing the information of pollen and other small particles in the measured environment are uploaded to the host computer for display.

[0071] Example 2

[0072] like Figure 4 As shown, the present invention further provides a method for monitoring the concentration of pollen bioaerosols, which is applied to the pollen bioaerosol concentration monitoring system in Example 1. The method includes steps S1 to S5.

[0073] Step S1: In response to a pollen bioaerosol concentration monitoring request, a time-domain electrical pulse signal of an elastic scattering field intensity signal and a fluorescent scattering field intensity signal generated when the air to be measured is irradiated by a light source is obtained.

[0074] In practical applications, a combination of a photoelectric detector and an acquisition card is used. The particles to be measured pass through the measurement light zone formed by the overlap of the measurement light spot and the sample flow one by one, and at the same time, elastic scattered light that can characterize the particle size parameters of the single particle to be measured and endogenous fluorescence that characterizes the content of fluorescent substances in the particles to be measured are generated. These light are received by the photoelectric detector and enter the data processing unit in the form of a time-domain electrical pulse signal. Useful information in the continuous pulse signal is extracted and processed, for example, noise in the signal is removed to obtain useful information.

[0075] Before executing step S2, Figure 5 As shown, the method further includes step S10:

[0076] Step S10: De-noising the time-domain electrical pulse signals of the elastic scattering field intensity signal and the fluorescent scattering field intensity signal to obtain de-noised time-domain electrical pulse signals of the elastic scattering field intensity signal and the fluorescent scattering field intensity signal.

[0077] S10 specifically includes:

[0078] Step S101: removing noise from a time-domain electrical pulse signal of an elastic scattering field intensity signal to obtain a first denoised pulse signal.

[0079] Step S102: Remove the noise of the time-domain electrical pulse signal of the fluorescence scattering field strength signal to obtain a second denoised pulse signal.

[0080] As a specific embodiment, since the optical path module and the acquisition card module inherently carry certain noise, preprocessing is required to distinguish the noise from the particle signal and perform further operations on the particle signal.

[0081] Step S103: Obtain the device noise of the pollen biological aerosol concentration monitoring system in Embodiment 1.

[0082] As a specific embodiment, as Figure 6 shown, calibrate a set of device noise data through blank sampling. Calculate the device noise using the five-point moving average method or other methods.

[0083] Device blank sampling signal: , where K is the acquisition signal of the scattered light channel, is the signal acquired by the acquisition card once, i = 0, 1, 2,..., n - 1, k[0] represents k0 acquired once in the acquisition signal K of the scattered light channel, and k[i] represents k acquired once in the acquisition signal K of the scattered light channel i . For example, for an acquisition card with a sampling rate of 20M, the single acquisition time is 50ns, that is, data is acquired every 50ns.

[0084] Due to the limitation of five-point linear smoothing, it is impossible to smooth and denoise the boundary signals. Therefore, boundary expansion is performed at the boundary, such as .

[0085] Perform denoising processing through signal expansion:

[0086] ;

[0087] Where: is the current point of the signal values of two points on each side of is the smoothed signal.

[0088] Find the noise baseline of the smoothed signal using the moving average method:

[0089] Select a window size of 5, remove the maximum and minimum values in the window, calculate the average value of the window, and move the window in steps of the window size to calculate the window average value. Finally, average all the average values to calculate the noise baseline.

[0090] Step S104: Remove the device noise in the first denoised pulse signal to obtain the time-domain electrical pulse signal of the denoised elastic scattering field strength signal.

[0091] Step S105: Remove the device noise from the second denoised pulse signal to obtain the time-domain electrical pulse signal of the fluorescence scattering field strength signal after denoising.

[0092] Step S2: Extract the characteristics of the time-domain electrical pulse signal of the elastic scattering field strength signal to obtain the elastic scattering characteristic signal.

[0093] The acquired signal can be regarded as a one-dimensional vector V. After the measured particle passes through the photosensitive area, the scattered optical signal is received by the photoelectric converter and converted into an electrical signal, which is then acquired by the acquisition card as an analog electrical signal, where this signal is defined as M. And the analog electrical signal is denoised by the calibrated device noise, and the denoised signal is regarded as a one-dimensional vector V. Perform a first-order difference on the vector V:

[0094] ; where represents the analog electrical signal acquired by the acquisition card once.

[0095] , where where, v i represents the analog electrical signal of the scattered light passing through the photoelectric converter acquired by the acquisition card once. For example, an acquisition card with a sampling rate of 20M samples data once every 50ns, that is, once every 50ns. V(i + 1) represents the data at the (i + 1)-th index in the vector V. X is the data vector after the first-order difference.

[0096] Perform a sign operation on the function after the difference and determine the sign of the trend:

[0097] ;

[0098] and , then ;

[0099] and , then ;

[0100] where, represents each data of the data vector X after the first-order difference; i is the vector index.

[0101] Adjust the sign according to the trend signal, and preset an upward (downward) flag threshold (usually take 1 - 2). When the number of consecutive upward signals of the Trend function is not greater than , then this signal is regarded as a downward trend.

[0102]

[0103] After performing a first-order difference on the Trend function to obtain R = diff(Trend), traverse the obtained difference function R. If R(i) = 2, then i + 1 is the characteristic signal of the elastic light scattering signal.

[0104] ;

[0105] Step S3: According to the elastic scattering characteristic signal, extract the characteristics of the time-domain electrical pulse signal of the fluorescence scattering field strength signal to obtain the fluorescence scattering characteristic signal.

[0106] In practical applications, information such as the characteristic signal of laser-induced fluorescence can be extracted based on the signal characteristics of the elastic light scattering signal. By finding the characteristic signal of the scattered light signal on the scattered signal M above and using the device noise baseline as a reference standard, the continuous signals found on both sides of the characteristic signal index are regarded as the characteristic intervals. According to the physical principle, the scattered light signal and the fluorescence signal of the same pollen passing through the photosensitive area are simultaneous, so the electrical signals collected by the acquisition card are synchronous. Therefore, the index of the characteristic interval of the scattered light signal can be directly moved to the fluorescence signal to find the characteristic interval of the fluorescence signal.

[0107] Step S4: Determine the total area of the pollen particles in the air to be measured according to the physical properties of the pollen particles and the fluorescence scattering characteristic signal.

[0108] S4 includes:

[0109] Step S41: Determine the width threshold and amplitude threshold of the fluorescence scattering characteristic signal of the pollen particles according to the physical properties of the pollen particles.

[0110] In practical applications, the width and amplitude characteristics of the laser-induced fluorescence characteristic signal can be extracted according to the physical properties of the particles.

[0111] The width of the characteristic interval of the electrical signal of the scattered light collected by the acquisition card is related to the light intensity of the photoelectric converter, and the magnitude of the scattered light intensity is related to the particle size. Due to the synchronism, the width of the characteristic interval of the fluorescence can be determined.

[0112] The magnitude of the fluorescence signal is related to organic molecules such as phenylalanine, tyrosine, tryptophan, nicotinamide adenine dinucleotide (NADH), and riboflavin that characterize biological activity inside the particles. Therefore, after meeting the threshold of a specific signal amplitude, this signal can be determined as the characteristic signal of the fluorescence signal. (This method is to remove the outliers caused by the noise of the fluorescence signal F)

[0113] Step S42: Determine the characteristic intervals greater than the width threshold and amplitude threshold from the fluorescence scattering characteristic signal.

[0114] Step S43: Apply the integration method to calculate the area of the characteristic interval, and obtain the total area of the pollen particles in the air to be measured.

[0115] In practical applications, under the condition that the laser-induced fluorescence characteristic signal satisfies the signal width and amplitude, the laser-induced fluorescence signal in the characteristic region is calculated according to the integration method. Specifically, to avoid the interference of fluorescence signal noise on the experimental results, the present invention uses the integration method to calculate the area of the fluorescence signal in the characteristic region.

[0116] ;

[0117] Considering that the single acquisition time of the acquisition card is fixed, the above formula can be simplified as:

[0118] ;

[0119] where x0, x1,... x n is the single electrical signal of the fluorescence signal within the characteristic interval; a and b are the left and right boundaries of the interval respectively; f(x) is the integration function, the interval [a, b] is divided into n equal parts, f(x0) = f(a), f(x n ) = f(b),

[0120] , f(x i ) is the corresponding function value.

[0121] Step S5: Determine the number of pollen particles in the air to be measured according to a preset area threshold of a single pollen particle and the total area of the pollen particles in the air to be measured.

[0122] In practical applications, according to the result calculated from the characteristic region, a pollen area threshold is preset in advance. Under the condition of meeting the requirements, it can be determined as pollen, and the signal of the characteristic region is saved, and the scattering signal and fluorescence signal of the characteristic region are saved (to reduce the memory consumption of the device).

[0123] In addition, the pollen bioaerosol concentration monitoring method further includes:

[0124] Calculate the volume of the air to be measured within the second preset time period according to the gas flow rate of the power unit; calculate the pollen bioaerosol concentration of the air to be measured according to the number and volume of the pollen particles in the air to be measured.

[0125] In practical applications, the number of pollen can be calculated according to the above formula. Since the gas flow rate (S) inhaled by the device is constant, the volume of the gas inhaled within the corresponding time (T) can be calculated, and the pollen bioaerosol concentration (C) can be calculated.

[0126] ;

[0127] Among them, the unit of S is L / min, T is s, and C is particles per cubic meter.

[0128] According to the concentration of pollen bioaerosol in the air to be measured, plot the concentration of pollen bioaerosol at each moment within the first preset time period for the air to be measured. Use a data visualization tool to plot a time series graph of the pollen bioaerosol concentration, etc. For example, calculate the concentration of pollen bioaerosol at different times according to the above.

[0129] Use the Internet of Things card technology to send the data to the cloud to generate a real-time pollen bioaerosol concentration map and distribution map. Combined with big data and artificial intelligence technologies, the pollen monitoring device can achieve more accurate prediction of the pollen bioaerosol concentration and improve the automation and intelligence level of the monitoring system. For example, as Figure 7 shown, at the server side, combine weather factors and environmental factors (such as temperature, humidity, and pressure) through a time series ARIMA model to analyze and predict the future pollen bioaerosol concentration, improving the automation and intelligence level of the monitoring system. Specifically, according to the number of pollen grains retrieved each time, the number of pollen grains retrieved can be accumulated every ten minutes, and the accumulated pollen number is transmitted. It also includes environmental factors: longitude, latitude, temperature, humidity, pressure, wind speed, wind direction, etc. Visualize the accumulated pollen data to generate a pollen time series graph, and save the accumulated pollen data and environmental factors (that is, longitude, latitude, temperature, humidity, pressure, wind speed, wind direction, etc.) as a json file. In addition, the web side can draw a pollen distribution map, concentration map, and pollen prediction map according to the transmitted data.

[0130] Figure 8 and Figure 9 are respectively schematic diagrams of signals of different pollens collected by the device. The abscissa is time (or the number of signals collected by the acquisition card each time), the ordinate is the signal voltage, the left side is the 405 scattering signal, and the right side is the 520 fluorescence signal. According to the spectrum, it can be clearly seen that the positions of the characteristic values of the fluorescence signal and the scattering signal are the same, which conforms to the physical principle discussed in Embodiment 1. In addition, it can be found that the greater the scattering signal intensity, the wider the signal width, indicating that the particle diameter is larger, so the induced fluorescence signal is larger, which satisfies the spectrum trend. Further, in the subsequent optimization process, it can be considered to distinguish pollen types according to the width of the abscissa interval.

[0131] The present invention obtains the concentration signal of pollen biological aerosol through elastic light scattering and laser-induced fluorescence technology, processes and analyzes the concentration signal of pollen biological aerosol to obtain the actual concentration value of pollen biological aerosol, enabling the present invention to operate in real time in the environment and provide accurate pollen biological aerosol concentration data, realizing efficient, accurate and real-time pollen monitoring, improving the automation degree of pollen monitoring, and providing data support for allergy patients, medical institutions and other users who need pollen biological aerosol concentration data, having broad application prospects and market value.

[0132] The technical features of the above embodiments can be combined arbitrarily. For the sake of concise description, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, it should be considered as the scope recorded in this specification.

[0133] Specific examples are used in this article to elaborate on the principle and implementation manner of the present invention. The description of the above embodiments is only used to help understand the method and its core idea of the present invention; at the same time, for those of ordinary skill in the art, according to the idea of the present invention, there will be changes in the specific implementation manner and application scope. In summary, the content of this specification should not be construed as a limitation to the present invention.

Claims

1. A pollen biological aerosol concentration monitoring system, characterized in that, The monitoring system includes: a power unit, a light source, a detector, a measurement chamber, and a data processing unit; The power unit is used to output a negative pressure power so that the air in the measured environment enters the measurement chamber to obtain the air to be measured; the air to be measured contains pollen particles; The light source is used to provide incident light for the air to be measured; The detector is used to receive the elastic scattering field strength signal and the fluorescence scattering field strength signal generated after the incident light irradiates the air to be measured, and generate a time-domain electrical pulse signal of the elastic scattering field strength signal and a time-domain electrical pulse signal of the fluorescence scattering field strength signal; The data processing unit is electrically connected to the detector; the data processing unit is used to determine the number of pollen particles in the air to be measured according to the time-domain electrical pulse signal of the elastic scattering field strength signal and the time-domain electrical pulse signal of the fluorescence scattering field strength signal, specifically including: Extract the characteristics of the time-domain electrical pulse signal of the elastic scattering field strength signal to obtain an elastic scattering characteristic signal; According to the elastic scattering characteristic signal, extract the characteristics of the time-domain electrical pulse signal of the fluorescence scattering field strength signal to obtain a fluorescence scattering characteristic signal; According to the physical properties of pollen particles and the fluorescence scattering characteristic signal, determine the total area of pollen particles in the air to be measured, specifically including: According to the physical properties of pollen particles, determine the width threshold and amplitude threshold of the fluorescence scattering characteristic signal of the pollen particles; Determine the characteristic interval greater than the width threshold and amplitude threshold from the fluorescence scattering characteristic signal; Apply the integration method to calculate the area of the fluorescence signal under the characteristic interval to obtain the total area of pollen particles in the air to be measured. The specific formula for calculating the area of the fluorescence signal under the characteristic interval is: Among them, x0, x1,... x n is the electrical signal of a single fluorescence signal within the characteristic interval; a and b are the left and right boundaries of the interval respectively; f(x) is the integral function, dividing the interval [a, b] into n equal parts, f(x0) = f(a), f(x n ) = f(b), , f(x i ) is the corresponding function value; According to a preset area threshold of a single pollen particle and the total area of pollen particles in the air to be measured, determine the number of pollen particles in the air to be measured.

2. The pollen biological aerosol concentration monitoring system according to claim 1, characterized in that, The measurement chamber includes an inlet, an outlet, a light source irradiation window, and a spectral detection window; The air to be measured enters the measurement chamber from the inlet; The light source provides incident light for the air to be measured from the light source irradiation window; The detector receives the elastic scattering field strength signal and the fluorescence scattering field strength signal generated after the incident light irradiates the pollen particles in the air to be measured from the spectral detection window; The air to be measured after being detected by the detector leaves the measurement chamber from the outlet.

3. The pollen biological aerosol concentration monitoring system according to claim 1, wherein The incident light is a laser.

4. The pollen biological aerosol concentration monitoring system according to claim 1, characterized in that, It further includes a host computer; The host computer is connected to the data processing unit; The host computer is used to display the number of pollen particles in the air to be measured at each moment within a first preset time period.

5. A method for monitoring the concentration of pollen biological aerosol, characterized in that, The method includes: In response to a pollen biological aerosol concentration monitoring request, obtain the time-domain electrical pulse signals of the elastic scattering field strength signal and the fluorescence scattering field strength signal generated after the air to be measured is irradiated by the light source; Extract the characteristics of the time-domain electrical pulse signal of the elastic scattering field strength signal to obtain an elastic scattering characteristic signal; According to the elastic scattering characteristic signal, extract the characteristics of the time-domain electrical pulse signal of the fluorescence scattering field strength signal to obtain a fluorescence scattering characteristic signal; Determine the total area of the pollen particles in the air to be measured according to the physical characteristics of the pollen particles and the fluorescence scattering characteristic signals, specifically including: Determine the width threshold and amplitude threshold of the fluorescence scattering characteristic signals of the pollen particles according to the physical characteristics of the pollen particles; Determine the characteristic intervals greater than the width threshold and amplitude threshold from the fluorescence scattering characteristic signals; Apply the integration method to calculate the area of the fluorescence signals in the characteristic intervals to obtain the total area of the pollen particles in the air to be measured; the specific formula for calculating the area of the fluorescence signals in the characteristic intervals is: Among them, x0, x1,... x n is the electrical signal of a single fluorescence signal within the characteristic interval; a and b are the left and right boundaries of the interval respectively; f(x) is the integral function, dividing the interval [a, b] into n equal parts, f(x0)=f(a), f(x n ) = f(b), , f(x i ) is the corresponding function value; Determine the number of pollen particles in the air to be measured according to a preset area threshold of a single pollen particle and the total area of the pollen particles in the air to be measured.

6. The pollen biological aerosol concentration monitoring method according to claim 5, characterized in that, Before performing the step of "extracting the characteristics of the time-domain electrical pulse signals of the elastic scattering field strength signals to obtain elastic scattering characteristic signals", the method further includes: Perform noise removal operations on the time-domain electrical pulse signals of the elastic scattering field strength signals and the fluorescence scattering field strength signals to obtain the time-domain electrical pulse signals of the denoised elastic scattering field strength signals and the time-domain electrical pulse signals of the denoised fluorescence scattering field strength signals.

7. The pollen biological aerosol concentration monitoring method according to claim 6, characterized in that, Performing noise removal operations on the time-domain electrical pulse signals of the elastic scattering field strength signals and the fluorescence scattering field strength signals to obtain the time-domain electrical pulse signals of the denoised elastic scattering field strength signals and the time-domain electrical pulse signals of the denoised fluorescence scattering field strength signals includes: Remove the noise of the time-domain electrical pulse signals of the elastic scattering field strength signals to obtain the first denoised pulse signals; Remove the noise of the time-domain electrical pulse signals of the fluorescence scattering field strength signals to obtain the second denoised pulse signals; Obtain the equipment noise of the pollen biological aerosol concentration monitoring system according to any one of claims 1-4; Remove the equipment noise in the first denoised pulse signals to obtain the time-domain electrical pulse signals of the denoised elastic scattering field strength signals; Remove the equipment noise in the second denoised pulse signals to obtain the time-domain electrical pulse signals of the denoised fluorescence scattering field strength signals.

8. The pollen biological aerosol concentration monitoring method according to claim 5, characterized in that The method further includes: Calculate the volume of the air to be measured in the second preset time period according to the gas flow rate of the power unit; Calculate the concentration of the pollen biological aerosol in the air to be measured according to the number of pollen particles in the air to be measured and the volume; 9. The pollen biological aerosol concentration monitoring method according to claim 8, characterized in that, Draw the concentration of the pollen biological aerosol at each moment in the first preset time period of the air to be measured according to the concentration of the pollen biological aerosol in the air to be measured.

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