Spectral detection method and system for pesticide residue concentration in plants

Abstract

The invention relates to the technical field of measuring or analyzing materials by utilizing an optical means, in particular to a spectrum detection method and a spectrum detection system for pesticide residue concentration in a plant. The fluorescence spectrum data comprises a fluorescence spectrum curve at an initial moment and fluorescence spectrum curves at different delay moments after the initial moment; and determining the corrected characteristic indexes of each influence fluorescence peak in the pesticide fluorescence peaks in the fluorescence spectrum curve at the initial moment and the characteristic indexes of other pesticide fluorescence peaks without overlapping peaks, and carrying out pesticide residue concentration measurement on the basis of the characteristic indexes. According to the invention, the measurement accuracy of the pesticide residue concentration in the plant is effectively improved.

Description

Technical Field

[0001] The present invention relates to the technical field of measuring or analyzing materials by optical means, and in particular to a spectral detection method and system for pesticide residue concentration in plants. Background Art

[0002] The problem of pesticide residues in plants is becoming increasingly serious. Traditional methods for detecting pesticide residue concentrations usually have problems such as complex operations, long time consumption, expensive equipment, and the need for professional technicians, which limits their application in large-scale screening. Spectral detection technology has gradually become a research hotspot due to its rapid, non-destructive and high sensitivity. Among them, fluorescence spectroscopy has unique advantages in pesticide residue detection due to its high selectivity and sensitivity. Fluorescence spectroscopy is based on the property that some pesticide molecules emit fluorescence under the irradiation of excitation light of a specific wavelength. It uses excitation to irradiate plants to excite the fluorescence signal of pesticide molecules, and then quantitatively analyzes pesticide residues in plants by measuring the fluorescence signal.

[0003] In the prior art, in the process of measuring pesticide residues in plants using fluorescence spectroscopy, naturally occurring fluorescent substances in plants (such as chlorophyll, flavonoids, and carotenoids) emit strong background fluorescence, which interferes with the detection of pesticide fluorescence signals and masks the fluorescence signals of pesticides. In this case, background correction can usually be used to deduct the background fluorescence intensity to extract the intensity of the target fluorescence signal for calculating the pesticide concentration. However, in actual measurements, the distribution of background fluorescence components such as chlorophyll and flavonoids in plants is not uniform, resulting in large differences in background signals between different individuals of the same plant. At the same time, if the chlorophyll fluorescence and flavonoid fluorescence in the plant sample overlap with the excitation wavelength or emission wavelength of the pesticide fluorescence signal, even after correction, there will be residual fluorescence interference, resulting in inaccurate measurement of pesticide residues. Summary of the invention

[0004] The object of the present invention is to provide a spectral detection method and system for the concentration of pesticide residues in plants, so as to solve the problem that the existing pesticide residue measurement is not accurate enough.

[0005] In order to solve the above technical problems, in a first aspect, the present invention provides a spectral detection method for the concentration of pesticide residues in plants, comprising the following steps: Acquiring fluorescence spectrum data of the plant to be detected, wherein the fluorescence spectrum data includes a fluorescence spectrum curve at an initial moment and fluorescence spectrum curves at different delayed moments after the initial moment; Determining characteristic indicators of each fluorescence peak in the fluorescence spectrum curve according to the peak distribution of each fluorescence peak in the fluorescence spectrum curve; Determining the pesticide representation degree of each fluorescence peak in the fluorescence spectrum curve at the initial moment according to the change of the characteristic index of the same fluorescence peak in the different fluorescence spectrum curves and the change of the peak curve of the same fluorescence peak; According to the pesticide expression degree, determine the pesticide fluorescence peak among the fluorescence peaks in the fluorescence spectrum curve at the initial moment, and determine the various influencing fluorescence peaks with overlapping peaks among all the pesticide fluorescence peaks, and determine the degree of influence of the influencing fluorescence peak by the overlapping peak according to the difference in the pesticide expression degree between the influencing fluorescence peak and its overlapping peak, and the offset of the influencing fluorescence peak in the fluorescence spectrum curve at different delay moments; Based on the degree of influence of the overlapping peaks and the characteristic indices corresponding to the fluorescence peaks and the overlapping peaks, the characteristic indices of each fluorescence peak influencing the fluorescence spectrum curve at the initial moment are corrected to obtain corrected characteristic indices; The pesticide residue concentration is measured according to the corrected characteristic indexes of each of the pesticide fluorescence peaks in the fluorescence spectrum curve at the initial moment that affects the fluorescence peak and the characteristic indexes of the remaining pesticide fluorescence peaks without overlapping peaks.

[0006] In combination with the first aspect above, in some possible implementations, determining a characteristic index of each fluorescence peak in the fluorescence spectrum curve includes: For any fluorescence peak in the fluorescence spectrum curve, according to the average difference between each wavelength in the fluorescence peak and the peak wavelength, and the fluorescence intensity corresponding to each wavelength in the fluorescence peak, determine the peak concentration index of the fluorescence peak; The characteristic index of the fluorescence peak is determined according to the peak concentration index of the fluorescence peak and the fluorescence intensity corresponding to the peak wavelength in the fluorescence peak, and the peak concentration index and the fluorescence intensity corresponding to the peak wavelength are both positively correlated with the characteristic index.

[0007] In combination with the first aspect above, in some possible implementations, determining the pesticide representation degree of each fluorescence peak in the fluorescence spectrum curve at the initial moment includes: Determine the fluorescence signal exhaustion time of each fluorescence peak in the fluorescence spectrum curve at the initial moment according to the change of each fluorescence peak in the fluorescence spectrum curve at the initial moment in the fluorescence spectrum curve at different delay moments, wherein the fluorescence signal exhaustion time corresponds to a delay moment; Determine the fluorescence signal attenuation time of each fluorescence peak in the fluorescence spectrum curve at the initial moment according to the time difference between the fluorescence signal exhaustion time of each fluorescence peak in the fluorescence spectrum curve at the initial moment and the initial moment; Determining the fluorescence signal change regularity index of each fluorescence peak in the fluorescence spectrum curve at the initial moment according to the change of the characteristic index of the same fluorescence peak in different fluorescence spectrum curves; According to the fluorescence signal attenuation time of each fluorescence peak in the fluorescence spectrum curve at the initial moment and the fluorescence signal change law index, the pesticide representation degree of each fluorescence peak in the fluorescence spectrum curve at the initial moment is determined, the fluorescence signal attenuation time is positively correlated with the pesticide representation degree, and the fluorescence signal change law index is negatively correlated with the pesticide representation degree.

[0008] In combination with the first aspect above, in some possible implementations, determining the fluorescence signal attenuation time of each fluorescence peak in the fluorescence spectrum curve at the initial moment includes: Determine the average value of the time difference between the fluorescence signal exhaustion time of each fluorescence peak in the fluorescence spectrum curve at the initial time and the initial time, and obtain the time difference mean; Determine the ratio of the time difference between the fluorescence signal exhaustion time of each fluorescence peak in the fluorescence spectrum curve at the initial time and the initial time to the average of the time differences, so as to obtain the fluorescence signal attenuation time of each fluorescence peak in the fluorescence spectrum curve at the initial time.

[0009] In combination with the first aspect above, in some possible implementations, determining the fluorescence signal change rule index of each fluorescence peak in the fluorescence spectrum curve at the initial moment includes: Arrange the characteristic indices of the same fluorescence peak in different fluorescence spectrum curves ending at the time when the fluorescence signal is exhausted in time sequence, and obtain a corresponding characteristic indicator sequence of each fluorescence peak in the fluorescence spectrum curve at the initial time; Determine the difference of each characteristic index according to the difference between each two adjacent characteristic indexes in the characteristic index sequence; The average value of all the characteristic indicator differences corresponding to the characteristic indicator sequence is determined, so as to obtain the fluorescence signal change regularity index of each fluorescence peak in the fluorescence spectrum curve at the initial moment.

[0010] In combination with the first aspect above, in some possible implementations, determining the degree of influence of the overlapping peaks that affects the fluorescence peak includes: Determine the average value of the difference in the pesticide expression degree between the fluorescence-affecting peak and its overlapping peak to obtain the pesticide expression degree difference value of the fluorescence-affecting peak; Determine the peak shift index of the influencing fluorescence peak according to the position change of the influencing fluorescence peak and the peak value of the fluorescence peak corresponding to the fluorescence spectrum curve at different delay times ending at the time of exhaustion of the fluorescence signal; The degree of influence of the overlapping peaks on the fluorescence peak is determined according to the pesticide expression degree difference value and the peak deviation index affecting the fluorescence peak. Both the pesticide expression degree difference value and the peak deviation index are positively correlated with the degree of influence of the overlapping peaks.

[0011] In combination with the first aspect above, in some possible implementations, the characteristic indicators affecting the fluorescence peak in the fluorescence spectrum curve at the initial moment are corrected to obtain the corrected characteristic indicators, including: Determining whether the degree of influence of the overlapping peak on the fluorescence peak is greater than a set influence degree threshold; If the degree of influence of the overlapping peak on the influencing fluorescence peak is greater than a set influence degree threshold, then according to the difference between each two adjacent characteristic indicators in the characteristic indicator sequence corresponding to the influencing fluorescence peak and the degree of influence of the overlapping peak on the influencing fluorescence peak, the characteristic indicator of the corresponding fluorescence peak in the fluorescence spectrum curve corresponding to the fluorescence signal of the overlapping peak of the influencing fluorescence peak is corrected at the moment when the fluorescence signal of the overlapping peak is exhausted, so as to obtain the corrected characteristic indicator of the influencing fluorescence peak; If the degree of influence of the overlapping peak that affects the fluorescence peak is not greater than the set influence degree threshold, then the characteristic index of the fluorescence peak influencing the fluorescence peak in the fluorescence spectrum curve at the initial moment is corrected according to the degree of influence of the overlapping peak that affects the fluorescence peak and the characteristic index of the overlapping peak that affects the fluorescence peak in the fluorescence spectrum curve at the initial moment, so as to obtain the corrected characteristic index of the fluorescence peak.

[0012] In combination with the first aspect above, in some possible implementations, the characteristic index of the fluorescence peak in the fluorescence spectrum curve corresponding to the moment when the fluorescence signal of the fluorescence peak is exhausted is corrected to obtain the corrected characteristic index affecting the fluorescence peak, and the corresponding calculation formula is: ; in, Indicates The corrected characteristic index affecting the fluorescence peak; Indicates a characteristic index of a corresponding fluorescence peak in the fluorescence spectrum curve corresponding to the moment when the fluorescence signal of the overlapping peak of the fluorescence peak is exhausted; Indicates The average decay rate of each characteristic indicator in the characteristic indicator sequence corresponding to the influencing fluorescence peak relative to the previous characteristic indicator; Indicates The degree to which the fluorescence peaks are affected by the overlapping peaks; The characteristic index affecting the fluorescence peak in the fluorescence spectrum curve at the initial moment is corrected to obtain the corrected characteristic index affecting the fluorescence peak. The corresponding calculation formula is: ; in, Indicates The corrected characteristic index affecting the fluorescence peak; The fluorescence spectrum curve at the initial moment is represented by The characteristic index that affects the fluorescence peak; The fluorescence spectrum curve at the initial moment is represented by The average of the characteristic indicators of the overlapping peaks affecting the fluorescence peak; Indicates The degree to which the fluorescence peak is affected by the overlapping peaks.

[0013] In combination with the first aspect above, in some possible implementations, measuring the pesticide residue concentration includes: The corrected characteristic index or characteristic index of the pesticide fluorescence peak in the fluorescence spectrum curve at the initial moment is used as the measurement characteristic index, and each measurement characteristic index is compared with the pre-calibrated characteristic index corresponding to the wavelength range of its pesticide fluorescence peak and the curve of the change with the pesticide concentration, so as to obtain the concentration of the pesticide component corresponding to the wavelength range of the pesticide fluorescence peak of each measurement characteristic index.

[0014] In order to solve the above technical problems, in a second aspect, the present invention also provides a spectral detection device for the concentration of pesticide residues in plants, the device comprising: A spectral data acquisition module, used to acquire fluorescence spectral data of the plant to be detected, wherein the fluorescence spectral data includes a fluorescence spectral curve at an initial moment and fluorescence spectral curves at different delayed moments after the initial moment; An optical characteristic index acquisition module, used to determine the characteristic index of each fluorescence peak in the fluorescence spectrum curve according to the peak distribution of each fluorescence peak in the fluorescence spectrum curve; A pesticide expression degree acquisition module is used to determine the pesticide expression degree of each fluorescence peak in the fluorescence spectrum curve at the initial moment according to the change of the characteristic index of the same fluorescence peak in the different fluorescence spectrum curves and the change of the peak curve of the same fluorescence peak; An influence degree acquisition module is used to determine the pesticide fluorescence peak among the fluorescence peaks in the fluorescence spectrum curve at the initial moment according to the pesticide expression degree, and determine the various influence fluorescence peaks with overlapping peaks among all the pesticide fluorescence peaks, and determine the influence degree of the influence of the overlapping peak on the influence fluorescence peak according to the difference in the pesticide expression degree between the influence fluorescence peak and its overlapping peak, and the offset of the influence fluorescence peak in the fluorescence spectrum curve at different delay moments; A characteristic index correction module, for correcting the characteristic indexes of each fluorescence peak in the fluorescence spectrum curve at the initial moment based on the degree of influence of the overlapping peaks and the characteristic indexes corresponding to the fluorescence peaks and their overlapping peaks, to obtain corrected characteristic indexes; The pesticide residue concentration measurement module is used to measure the pesticide residue concentration according to the corrected characteristic indicators of each pesticide fluorescence peak in the fluorescence spectrum curve at the initial moment and the characteristic indicators of the remaining pesticide fluorescence peaks without overlapping peaks.

[0015] To solve the above technical problems, in a third aspect, the present invention further provides a spectral detection system for pesticide residue concentration in plants, comprising a memory and a processor. The memory is used to store executable program code, and the processor is used to call and run the executable program code from the memory, so that the device executes the method in the above first aspect or any possible implementation of the first aspect.

[0016] To solve the above technical problems, in a fourth aspect, the present invention further provides a computer program product, which includes: a computer program code, when the computer program code runs on a computer, enables the computer to execute the method in the above first aspect or any possible implementation of the first aspect.

[0017] To solve the above technical problems, in a fifth aspect, the present invention further provides a computer-readable storage medium, which stores a computer program code. When the computer program code runs on a computer, the computer executes the method in the above first aspect or any possible implementation of the first aspect.

[0018] The present invention has the following beneficial effects: by utilizing multi-time fluorescence measurement, the fluorescence spectrum curves of the plant to be detected at the initial moment and at different delayed moments after the initial moment are obtained, and then according to the peak distribution of each fluorescence peak in the fluorescence spectrum curve, the characteristics of each fluorescence peak in the fluorescence spectrum curve are extracted to obtain the characteristic index of the fluorescence peak, and then according to the change of the characteristic index of the same fluorescence peak in different fluorescence spectrum curves and the change of the peak curve of the same fluorescence peak, the pesticide representation degree of each fluorescence peak in the fluorescence spectrum curve at the initial moment is determined, so as to screen out the pesticide fluorescence peaks in each fluorescence peak in the fluorescence spectrum curve at the initial moment, so as to effectively avoid the short-lived components of the plant background fluorescence, thereby enhancing the resolution of the pesticide fluorescence signal; by identifying the overlapping peaks in all the pesticide fluorescence peaks Each influencing fluorescence peak is determined according to the difference in the degree of pesticide expression between the influencing fluorescence peak and its overlapping peak, as well as the offset of the influencing fluorescence peak in the fluorescence spectrum curve at different delay times. The degree of influence of the overlapping peak reflects whether the overlapping peak is a plant background or a pesticide fluorescence peak. Therefore, based on the degree of influence of the overlapping peak and the characteristic indicators corresponding to the influencing fluorescence peak and its overlapping peak, the characteristic indicators of each influencing fluorescence peak in the fluorescence spectrum curve at the initial moment can be corrected to avoid the error caused by spectral overlap, thereby obtaining the corrected true characteristic indicators of each influencing fluorescence peak; finally, based on the true characteristic indicators of the pesticide fluorescence peak in the fluorescence spectrum curve at the initial moment, accurate pesticide residue concentration measurement is performed, which effectively improves the accuracy of pesticide residue concentration measurement. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] In order to more clearly illustrate the technical solutions and advantages in the embodiments of the present invention or the prior art, the drawings required for use in the embodiments or the prior art descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0020] Figure 1 A flowchart of the steps of a spectral detection method for pesticide residue concentration in plants according to an embodiment of the present invention; Figure 2 A schematic structural diagram of a fluorescence detection system according to an embodiment of the present invention; Figure 3 It is a schematic diagram of a fluorescence spectrum diagram according to an embodiment of the present invention. DETAILED DESCRIPTION

[0021] In order to clearly illustrate the technical features of the present invention, the present invention is described in detail below through specific implementation methods in conjunction with the accompanying drawings.

[0022] Embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although certain embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be construed as being limited to the embodiments described herein, which are instead provided for a more thorough and complete understanding of the present invention. It should be understood that the drawings and embodiments of the present invention are only for exemplary purposes and are not intended to limit the scope of protection of the present invention.

[0023] It should be understood that the various steps described in the method embodiments of the present invention may be performed in different orders and / or in parallel. In addition, the method embodiments may include additional steps and / or omit the steps shown. The scope of the present invention is not limited in this respect.

[0024] The term "including" and its variations used herein are open inclusions, i.e., "including but not limited to". The term "based on" means "based at least in part on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". The relevant definitions of other terms will be given in the following description.

[0025] It should be noted that the concepts such as "first" and "second" mentioned in the present invention are only used to distinguish different devices, modules or units, and are not used to limit the order or interdependence of the functions performed by these devices, modules or units.

[0026] Although operations or steps are described in a specific order in the drawings in the embodiments of the present invention, it should not be understood that it is required to perform these operations or steps in the specific order shown or in a serial order, or that all the operations or steps shown must be performed to obtain the desired results. In the embodiments of the present invention, these operations or steps may be performed in series; these operations or steps may also be performed in parallel; or some of these operations or steps may be performed.

[0027] At the same time, it is understood that the data involved in the technical solution of the present invention (including but not limited to the data itself, the acquisition or use of the data) shall comply with the requirements of the relevant laws, regulations and relevant provisions. Unless otherwise defined, all technical and scientific terms used in the present invention have the same meanings as those generally understood by technicians in the technical field of the present invention, and all parameters or indicators in the formulas involved in the present invention are normalized values ​​that eliminate the influence of dimensions.

[0028] In order to solve the problem of inaccurate existing pesticide residue measurements, an embodiment of the present invention provides a spectral detection method and system for pesticide residue concentration in plants. By utilizing multi-time point fluorescence measurement, fluorescence spectrum curves at the initial moment and different delayed moments after the initial moment are obtained, and these fluorescence spectrum curves are analyzed to distinguish between plant background fluorescence signals and pesticide fluorescence signals. By considering the influence of overlapping peaks on pesticide fluorescence signals, a more accurate pesticide residue concentration is obtained, thereby effectively improving the measurement accuracy of pesticide residue concentration.

[0029] A spectral detection method and system for pesticide residue concentration in plants provided by an embodiment of the present invention will be described in detail below in conjunction with the accompanying drawings.

[0030] Figure 1 FIG. 1 is a schematic diagram showing a basic flow chart of a spectral detection method for pesticide residue concentration in plants provided by an embodiment of the present invention. Figure 1 As shown, the method specifically comprises the following steps: Step S100: Acquire fluorescence spectrum data of the plant to be detected, wherein the fluorescence spectrum data includes a fluorescence spectrum curve at an initial moment and fluorescence spectrum curves at different delayed moments after the initial moment.

[0031] In the process of fluorescence spectrum detection of the plants to be tested, pesticide residues and plant background (chlorophyll, flavonoids, carotenoids, etc.) may form characteristic fluorescence peaks. When performing simple background correction, the spectrum peaks obtained from different background detections at different locations of the plant will be different. If there are overlapping peaks, it will cause greater errors. Therefore, in order to ensure more accurate acquisition of the concentration of pesticide residues in plants, based on the difference in plant background and pesticide fluorescence lifetime, the fluorescence lifetime of plant background fluorescence (such as chlorophyll, flavonoids) is usually short (nanosecond level), while pesticide molecules may have a longer fluorescence lifetime (microsecond level). Different delay times are used to obtain fluorescence signals to distinguish pesticides from plant background signals.

[0032] Based on the above analysis, when it is necessary to measure the pesticide residue concentration of plants, the fluorescence spectrum data of the plants to be detected are collected by using a fluorescence detection system through multi-time point fluorescence measurement to obtain the fluorescence spectrum data of the plants to be detected. The fluorescence spectrum data includes the fluorescence spectrum curve at the initial moment and the fluorescence spectrum curves at different delayed moments after the initial moment.

[0033] In this embodiment, when the fluorescence spectrum data of the plant to be detected is collected by using the fluorescence detection system, Figure 2As shown in the figure, the fluorescence detection system uses the FLS1000 fluorescence spectrometer as the detection equipment, and selects light-emitting diodes (LEDs) of different wavelengths as the excitation light source. Then, according to the fluorescence characteristics of the pesticide molecules that may be contained in the plants to be detected, the excitation wavelength is selected, and the surface of the individual plants to be detected is gradually irradiated by adjusting the wavelength range of the LED light source (420-700nm) to ensure that the fluorescence response band of the target pesticide is covered. After receiving the fluorescence signal emitted by the plant to be detected through the filter, the fluorescence spectrometer starts the time-resolved mode for acquisition. In order to record the dynamic changes of the fluorescence signal, the acquisition is delayed at a time interval of 2ns to ensure that the instantaneous intensity changes of the fluorescence decay process can be captured at each delayed moment. The entire acquisition process lasts long enough until the fluorescence signal is completely decayed below the noise level. The data acquisition software records the raw data of the fluorescence intensity changes over time collected by the fluorescence spectrometer in real time, and stores the data in digital form. During the acquisition process, the noise level and background light need to be monitored to ensure data quality. The stored raw data is processed by computer software and plotted into a fluorescence spectrum diagram, which includes the fluorescence spectrum curve at the initial moment and the fluorescence spectrum curves at different delayed moments after the initial moment. These fluorescence spectrum curves reflect the change of fluorescence intensity over time and can be used to analyze the fluorescence lifetime characteristics of different components. At the same time, they show the fluorescence intensity distribution at different wavelengths, which can be used to determine the position and range of the characteristic fluorescence peak of the pesticide.

[0034] For ease of understanding, Figure 3 A schematic diagram of a fluorescence spectrum is given. In this fluorescence spectrum, there are two obvious fluorescence peaks at the initial moment (i.e., time 0). The left fluorescence peak disappears at about 6 nanoseconds as time goes by, which is the background signal; while the right fluorescence peak decays as time goes by but always exists, which is more likely to be pesticide.

[0035] The fluorescence spectrum curve at the initial moment (i.e., the moment when time is 0) and the fluorescence spectrum curves at different delayed moments after the initial moment included in the fluorescence spectrum diagram obtained by the fluorescence detection system constitute the fluorescence spectrum data of the plant to be detected. It should be understood that Figure 2 The fluorescence detection system provided is only a specific acquisition system structure. On the basis of ensuring that the fluorescence spectrum data of the plant to be detected can be obtained, other fluorescence detection systems can also be used to collect the fluorescence spectrum data, which is not specifically limited here.

[0036] Step S200: determining a characteristic index of each fluorescence peak in the fluorescence spectrum curve according to the peak distribution of each fluorescence peak in the fluorescence spectrum curve.

[0037] The fluorescence spectrum curve at the initial moment has not been attenuated, while the fluorescence spectrum curve at different delay moments will gradually attenuate with the extension of time. For the plant background fluorescence in the fluorescence spectrum curve, its decay rate is faster and the fluorescence lifetime is shorter, while for the pesticide fluorescence in the fluorescence spectrum curve, its decay rate is slower and the fluorescence lifetime is longer, thereby achieving the distinction between plant background fluorescence and pesticide fluorescence. However, in the fluorescence spectrum curve, if the concentration of pesticide residues is weak, its fluorescence lifetime will also decrease. In order to prevent the fluorescence peak of pesticides with lower concentrations from being misjudged as background signals, and to facilitate the subsequent measurement of pesticide concentrations, it is necessary to obtain the characteristic indicators of each fluorescence peak based on the peak distribution of each fluorescence peak in the fluorescence spectrum curve.

[0038] In this embodiment, according to the peak distribution of each fluorescence peak in the fluorescence spectrum curve, the characteristic index of each fluorescence peak in the fluorescence spectrum curve is determined, and the implementation steps include: For any fluorescence peak in the fluorescence spectrum curve, according to the average difference between each wavelength in the fluorescence peak and the peak wavelength, and the fluorescence intensity corresponding to each wavelength in the fluorescence peak, determine the peak concentration index of the fluorescence peak; The characteristic index of the fluorescence peak is determined according to the peak concentration index of the fluorescence peak and the size of the fluorescence intensity corresponding to the peak wavelength in the fluorescence peak. The peak concentration index and the size of the fluorescence intensity corresponding to the peak wavelength are both positively correlated with the characteristic index.

[0039] For the above steps, as an example, for any fluorescence spectrum curve in the fluorescence spectrum curves at the initial moment and at different delayed moments after the initial moment, the fluorescence peaks of the fluorescence spectrum curve are obtained by the find_peaks function. At this time, the characteristic index of each fluorescence peak can be expressed as: ; in, represents the first Characteristic index of each fluorescence peak; represents the first The fluorescence intensity corresponding to the peak wavelength within each fluorescence peak; represents the first Peak concentration index of each fluorescence peak; represents the first The fluorescence peak wavelength; represents the first The peak wavelength within each fluorescence peak; represents the first The fluorescence peak The fluorescence intensity corresponding to the wavelength; represents the first The number of wavelengths within the fluorescence peak, i.e. The number of data points within a fluorescence peak.

[0040] In the above calculation formula, by calculating the first The average value of the product of the wavelength difference between the different fluorescence intensities in each fluorescence peak and the peak fluorescence intensity and the corresponding spectral fluorescence intensity is used to reflect the The concentration of the fluorescence peak distribution, combined with the The peak fluorescence intensity within the fluorescence peak, that is, the fluorescence intensity corresponding to the peak wavelength, is used to determine the The characteristic index of the fluorescence peak is The shape characteristics of each fluorescence peak are quantified.

[0041] Step S300: Determine the pesticide representation degree of each fluorescence peak in the fluorescence spectrum curve at the initial moment according to the change of the characteristic index of the same fluorescence peak in the different fluorescence spectrum curves and the change of the peak curve of the same fluorescence peak.

[0042] Since the life span of plant background fluorescence in the fluorescence spectrum curve is short, while the life span of pesticide fluorescence is long, by analyzing the change of the peak curve of the same fluorescence peak in different fluorescence spectrum curves, the life span of each fluorescence peak in the fluorescence spectrum curve at the initial moment can be identified, so as to determine the possibility that each fluorescence peak in the fluorescence spectrum curve at the initial moment belongs to pesticide fluorescence, thereby achieving the distinction between pesticide fluorescence and plant background fluorescence. At the same time, even if the concentration of pesticide residues in plants is weak, the change difference of the shape of the spectrum curve is small during the attenuation process of its fluorescence signal, that is, the difference in the change of characteristic indicators over time is small, while the attenuation difference of the plant background fluorescence signal is large. Therefore, combined with the characteristic indicators of each fluorescence peak changing over time, it can also assist in determining the possibility that each fluorescence peak in the fluorescence spectrum curve at the initial moment belongs to pesticide fluorescence, thereby ultimately achieving accurate distinction between pesticide fluorescence and plant background fluorescence.

[0043] In this embodiment, the pesticide representation degree of each fluorescence peak in the fluorescence spectrum curve at the initial moment is determined, and the implementation steps include: Determine the fluorescence signal exhaustion time of each fluorescence peak in the fluorescence spectrum curve at the initial moment according to the change of each fluorescence peak in the fluorescence spectrum curve at the initial moment in the fluorescence spectrum curve at different delay moments, wherein the fluorescence signal exhaustion time corresponds to a delay moment; Determine the fluorescence signal attenuation time of each fluorescence peak in the fluorescence spectrum curve at the initial moment according to the time difference between the fluorescence signal exhaustion time of each fluorescence peak in the fluorescence spectrum curve at the initial moment and the initial moment; Determining the fluorescence signal change regularity index of each fluorescence peak in the fluorescence spectrum curve at the initial moment according to the change of the characteristic index of the same fluorescence peak in different fluorescence spectrum curves; According to the fluorescence signal attenuation time of each fluorescence peak in the fluorescence spectrum curve at the initial moment and the fluorescence signal change law index, the pesticide representation degree of each fluorescence peak in the fluorescence spectrum curve at the initial moment is determined, the fluorescence signal attenuation time is positively correlated with the pesticide representation degree, and the fluorescence signal change law index is negatively correlated with the pesticide representation degree.

[0044] For the above steps, as an example, since the fluorescence reaction at the initial moment is the strongest, for any fluorescence peak in the fluorescence spectrum curve at the initial moment, the fluorescence peak is recorded as the target fluorescence peak. According to the wavelength range of the target fluorescence peak, the corresponding fluorescence peaks representing the same fluorescence peak in the fluorescence spectrum curve at each delayed moment can be determined. According to the changes of these corresponding fluorescence peaks, the fluorescence signal exhaustion time of the target fluorescence peak can be determined. Considering that the peak value change after the fluorescence peak exhaustion time is very small, while the peak value change in the previous attenuation process is large, the fluorescence signal exhaustion time is determined by comparing the difference between the peak value difference of each corresponding fluorescence peak and its two adjacent corresponding fluorescence peaks. In this embodiment, the fluorescence intensity corresponding to the peak wavelength of each corresponding fluorescence peak of the target fluorescence peak is determined, and the absolute value of the difference between the fluorescence intensity corresponding to the peak wavelength of each corresponding fluorescence peak and its two corresponding fluorescence peaks before and after is determined, which are recorded as the first difference absolute value and the second difference absolute value, respectively. The absolute value of the difference between the first difference absolute value and the second difference absolute value is calculated, which is recorded as the third difference absolute value. Since there are multiple corresponding fluorescence peaks in the fluorescence spectrum curve of the target fluorescence peak at each delayed moment, a third difference absolute value will correspond to a corresponding fluorescence peak at a delayed moment. Therefore, the maximum value of all the third difference absolute values ​​corresponding to the target fluorescence peak is determined, and the delayed moment of the corresponding fluorescence peak corresponding to the maximum value is taken as the fluorescence signal exhaustion moment of the target fluorescence peak.

[0045] Furthermore, according to the time difference between the exhaustion time of the fluorescence signal of each fluorescence peak in the fluorescence spectrum curve at the initial time and the initial time, the attenuation time of the fluorescence signal of each fluorescence peak in the fluorescence spectrum curve at the initial time is determined, and the corresponding calculation formula is: ; in, The fluorescence spectrum curve at the initial moment The fluorescence signal decay time of each fluorescence peak; The fluorescence spectrum curve at the initial moment The moment when the fluorescence signal of a fluorescence peak is exhausted; The fluorescence spectrum curve at the initial moment The initial moment of the fluorescence peak; The fluorescence spectrum curve at the initial moment The moment when the fluorescence signal of a fluorescence peak is exhausted; The fluorescence spectrum curve at the initial moment The initial moment of the fluorescence peak; Indicates the number of fluorescence peaks in the fluorescence spectrum curve at the initial moment; The fluorescence spectrum curve at the initial moment The difference in the timing of the fluorescence peaks; represents the mean of the time differences.

[0046] In the above calculation formula, by calculating the fluorescence spectrum curve at the initial moment The total time from the fluorescence peak to the disappearance of the fluorescence signal , and the total duration The average time for the fluorescence signals of all fluorescence peaks in the fluorescence spectrum curve at the initial moment to disappear Make a ratio to the total time Normalization is performed to obtain the fluorescence spectrum curve at the initial moment. The fluorescence signal decay time of the first fluorescence peak is used to characterize the The lifetime of each fluorescence peak. The longer the lifetime, the The more fluorescence peaks there are, the more likely it is pesticide fluorescence. The more fluorescence peaks there are, the more likely they are plant background fluorescence.

[0047] After determining the characteristic index of each fluorescence peak in each fluorescence spectrum curve through the above steps, the characteristic index of the same fluorescence peak in different fluorescence spectrum curves ending at the time when the fluorescence signal is exhausted is arranged in order from front to back, that is, the characteristic index of any fluorescence peak in the fluorescence spectrum curve at the initial moment and the corresponding fluorescence peak in the fluorescence spectrum curve at each delayed moment ending at the time when the fluorescence signal is exhausted is arranged, so as to obtain the characteristic index sequence of each fluorescence peak in the fluorescence spectrum curve at the initial moment. Then, according to the difference between each adjacent two characteristic indexes in the characteristic index sequence, the change law of the characteristic index of the fluorescence peak over time is quantified, and the fluorescence signal change law index of each fluorescence peak in the fluorescence spectrum curve at the initial moment is determined. The corresponding calculation formula is: ; in, The fluorescence spectrum curve at the initial moment The fluorescence signal change regularity index of each fluorescence peak; and They represent the fluorescence spectrum curve at the initial moment. The first in the characteristic index sequence of the fluorescence peak The characteristic index and characteristic indicators; The fluorescence spectrum curve at the initial moment The total number of characteristic indicators in the characteristic indicator sequence of each fluorescence peak.

[0048] In the above calculation formula, for the same fluorescence peak in the fluorescence spectrum curve at the initial moment and at different delayed moments after the initial moment, the characteristic index difference of the fluorescence peaks at two adjacent moments is calculated until the fluorescence signal is exhausted. The average of is used to represent the overall decay rate of the fluorescence peak signal. This indicates that the greater the decay rate, the more likely the corresponding fluorescence peak is the fluorescence peak of the plant background.

[0049] For each fluorescence peak in the fluorescence spectrum curve at the initial moment, the greater the fluorescence signal change law, the more likely the corresponding fluorescence peak is a pesticide fluorescence peak, and the longer the fluorescence signal lifetime, the more likely it is a pesticide fluorescence peak. Therefore, according to the fluorescence signal attenuation time of each fluorescence peak in the fluorescence spectrum curve at the initial moment and the fluorescence signal change law index, the pesticide representation degree of each fluorescence peak in the fluorescence spectrum curve at the initial moment can be determined, and the corresponding calculation formula is: ; in, The fluorescence spectrum curve at the initial moment The degree of pesticide expression of each fluorescence peak; The fluorescence spectrum curve at the initial moment The fluorescence signal change regularity index of each fluorescence peak; The fluorescence spectrum curve at the initial moment The fluorescence signal decay time of each fluorescence peak; Represents an exponential function with the natural constant e as base.

[0050] In the above calculation formula, the first The smaller the value of the fluorescence signal change law index of the first fluorescence peak, the The more the fluorescence signal change law of the first fluorescence peak conforms to the attenuation characteristics of pesticides, and the The longer the fluorescence signal decay time of a fluorescence peak is, the The greater the probability that the fluorescence peak is the corresponding fluorescence peak of the pesticide.

[0051] Step S400: Determine the pesticide fluorescence peak among the fluorescence peaks in the fluorescence spectrum curve at the initial moment according to the pesticide expression degree, and determine the influencing fluorescence peaks of overlapping peaks among all the pesticide fluorescence peaks, and determine the degree to which the influencing fluorescence peak is affected by the overlapping peak according to the difference in the pesticide expression degree between the influencing fluorescence peak and its overlapping peak, and the offset of the influencing fluorescence peak in the fluorescence spectrum curve at the different delayed moments.

[0052] A pesticide expression level threshold is preset, and the specific value of the pesticide expression level threshold can be reasonably set as needed. In this embodiment, the pesticide expression level threshold is set to 0.7. The pesticide expression level of each fluorescence peak in the fluorescence spectrum curve at the initial moment is compared with the pesticide expression level threshold. If the pesticide expression level is greater than the pesticide expression level threshold, the corresponding fluorescence peak is determined as the pesticide fluorescence peak, otherwise the corresponding fluorescence peak is determined as the plant background fluorescence peak, so that the pesticide fluorescence peak in each fluorescence peak in the fluorescence spectrum curve at the initial moment can be determined.

[0053] After obtaining the pesticide fluorescence peaks in each fluorescence peak in the fluorescence spectrum curve at the initial moment, if there is no interference, the pesticide residue concentration in the plant can be obtained based on the characteristic indicators of these pesticide fluorescence peaks. However, due to the interference in the actual measurement, the interference of environmental noise can be eliminated by the change law of the fluorescence peak over time, and other types of interference, such as some pesticide fluorescence peaks and plant background fluorescence peaks or other pesticide fluorescence peaks forming overlapping bands, then the pesticide concentration represented by some pesticide fluorescence peaks will be affected by the plant background fluorescence peak or other pesticide fluorescence peaks. There will be errors. For example, the overlap of plant background fluorescence peaks and pesticide fluorescence peaks will lead to the enhancement of pesticide signals and fail to accurately reflect the actual pesticide concentration. At this time, it is necessary to calibrate the characteristic indicators of these pesticide fluorescence peaks.

[0054] Therefore, the various influencing fluorescence peaks with overlapping peaks among all the pesticide fluorescence peaks in the fluorescence spectrum curve at the initial moment are determined. The influencing fluorescence peak refers to the pesticide fluorescence peak that will be affected by other fluorescence peaks, and the overlapping peak is the other fluorescence peak that affects the influencing fluorescence peak. The specific method of determining the various influencing fluorescence peaks with overlapping peaks among all the pesticide fluorescence peaks in the fluorescence spectrum curve at the initial moment can be reasonably selected as needed. For example, whether the pesticide fluorescence peak is an influencing fluorescence peak with overlapping peaks can be determined based on the waveform symmetry on both sides of the peak of each pesticide fluorescence peak. If the symmetry of the waveform on both sides of the peak is low, the pesticide fluorescence peak is considered to be an influencing fluorescence peak, and at the same time, the fluorescence peaks with the same low waveform symmetry on both sides of the peak adjacent to the influencing fluorescence peak are regarded as overlapping peaks of the influencing fluorescence peak.

[0055] After determining the influencing fluorescence peaks of the overlapping peaks among all the pesticide fluorescence peaks, the center position of the influencing fluorescence peak after the overlap will be shifted due to the influence of the overlapping peak, and the larger the shift position, the more it means that the influencing fluorescence peak is affected by the overlapping peak. At the same time, the greater the difference in the pesticide representation degree between the influencing fluorescence peak and its overlapping peak, the faster the overlapping peak decays. The more the influencing fluorescence peak is affected by the overlapping peak, the less its fluorescence signal can represent the actual pesticide residue level.

[0056] In this embodiment, the degree to which the influencing fluorescence peak is affected by the overlapping peak is determined according to the difference in the pesticide expression degree between the influencing fluorescence peak and its overlapping peak, and the offset of the influencing fluorescence peak in the fluorescence spectrum curve at the different delay times, and the implementation steps include: Determine the average value of the difference in the pesticide expression degree between the fluorescence-affecting peak and its overlapping peak to obtain the pesticide expression degree difference value of the fluorescence-affecting peak; Determine the peak shift index of the influencing fluorescence peak according to the position change of the influencing fluorescence peak and the peak value of the fluorescence peak corresponding to the fluorescence spectrum curve at different delay times ending at the time of exhaustion of the fluorescence signal; The degree of influence of the overlapping peaks on the fluorescence peak is determined according to the pesticide expression degree difference value and the peak deviation index affecting the fluorescence peak. Both the pesticide expression degree difference value and the peak deviation index are positively correlated with the degree of influence of the overlapping peaks.

[0057] For the above steps, as an example, for each fluorescence peak that has an overlapping peak among all the pesticide fluorescence peaks in the fluorescence spectrum curve at the initial moment, since each fluorescence peak that has an impact may be affected by more than one overlapping peak at the same time, the absolute value of the difference between the impact fluorescence peak and each of its overlapping peaks is determined, and the average value of the absolute value of the difference between the impact fluorescence peak and its respective overlapping peaks is used as the difference value of the pesticide representation degree of the impact fluorescence peak. At the same time, the position of the peak value of the impact fluorescence peak and the corresponding fluorescence peak in the fluorescence spectrum curve at different delayed moments up to the moment when the fluorescence signal is exhausted is determined, and then the distance between the positions of each two adjacent peaks is calculated, the average value of all distances is determined, and the average distance is obtained, and the average distance is used as the peak deviation index of the impact fluorescence peak.

[0058] Therefore, according to the pesticide representation degree difference value and peak shift index corresponding to each influencing fluorescence peak with overlapping peaks among all the pesticide fluorescence peaks in the fluorescence spectrum curve at the initial moment, the degree of influence of each influencing fluorescence peak with overlapping peaks among all the pesticide fluorescence peaks in the fluorescence spectrum curve at the initial moment can be determined, and the corresponding calculation formula is: ; in, Indicates that there are overlapping peaks among all the pesticide fluorescence peaks in the fluorescence spectrum curve at the initial moment. The degree to which the fluorescence peak is affected by the overlapping peaks; Indicates that there are overlapping peaks among all the pesticide fluorescence peaks in the fluorescence spectrum curve at the initial moment. A peak shift index that affects the fluorescence peak; Indicates that there are overlapping peaks among all the pesticide fluorescence peaks in the fluorescence spectrum curve at the initial moment. The pesticides that affect the fluorescence peaks represent the degree of difference.

[0059] In the above calculation formula, the first peak with overlapping peaks among all the pesticide fluorescence peaks in the fluorescence spectrum curve at the initial moment is calculated. The difference value of the pesticide expression level and the peak shift index that affect the fluorescence peak are used to determine the The greater the difference value of the pesticide degree and the peak shift index, the greater the influence of the overlapping peaks on the fluorescence peak. The higher the degree to which an influencing fluorescence peak is affected by its overlapping peak, the greater the corresponding value of the degree of influence of the overlapping peak.

[0060] Step S500: based on the degree of influence of the overlapping peaks and the characteristic indices corresponding to the fluorescence peaks and their overlapping peaks, correct the characteristic indices of each fluorescence peak influencing the fluorescence spectrum curve at the initial moment to obtain corrected characteristic indices.

[0061] For each influencing fluorescence peak in the fluorescence spectrum curve at the initial moment, the shape of the spectrum curve at the moment when the overlapping peak disappears is a real characteristic peak. If the overlapping peak is a plant background fluorescence peak, that is, the influencing fluorescence peak is greatly affected by the overlapping peak, then the attenuation difference between the overlapping peak and the influencing fluorescence peak representing the pesticide fluorescence signal is too large. When the overlapping peak disappears, the influencing fluorescence peak representing the pesticide fluorescence signal has only undergone a weak signal attenuation. Therefore, the characteristic index of the influencing fluorescence peak in the fluorescence spectrum curve at the initial moment can be corrected according to the attenuation of the characteristic index of the influencing fluorescence peak and the degree of influence of the overlapping peak on the influencing fluorescence peak, so as to obtain the corrected characteristic index. If the overlapping peak is another pesticide fluorescence peak, that is, the influencing fluorescence peak is less affected by the overlapping peak, since both the influencing fluorescence peak and the overlapping peak have a long fluorescence lifetime, as time goes by, the attenuation rate of their characteristic indexes can represent the real attenuation law. At this time, the characteristic index of the influencing fluorescence peak in the fluorescence spectrum curve at the initial moment can be corrected according to the influence relationship between each other.

[0062] In this embodiment, based on the degree of influence of the overlapping peaks and the characteristic indicators corresponding to the fluorescence peaks and their overlapping peaks, the characteristic indicators of the respective fluorescence peaks influencing the fluorescence spectrum curve at the initial moment are corrected to obtain the corrected characteristic indicators, and the implementation steps include: Determining whether the degree of influence of the overlapping peak on the fluorescence peak is greater than a set influence degree threshold; If the degree of influence of the overlapping peak on the influencing fluorescence peak is greater than a set influence degree threshold, then according to the difference between each two adjacent characteristic indicators in the characteristic indicator sequence corresponding to the influencing fluorescence peak and the degree of influence of the overlapping peak on the influencing fluorescence peak, the characteristic indicator of the corresponding fluorescence peak in the fluorescence spectrum curve corresponding to the fluorescence signal of the overlapping peak of the influencing fluorescence peak is corrected at the moment when the fluorescence signal of the overlapping peak is exhausted, so as to obtain the corrected characteristic indicator of the influencing fluorescence peak; If the degree of influence of the overlapping peak that affects the fluorescence peak is not greater than the set influence degree threshold, then the characteristic index of the fluorescence peak influencing the fluorescence peak in the fluorescence spectrum curve at the initial moment is corrected according to the degree of influence of the overlapping peak that affects the fluorescence peak and the characteristic index of the overlapping peak that affects the fluorescence peak in the fluorescence spectrum curve at the initial moment, so as to obtain the corrected characteristic index of the fluorescence peak.

[0063] For the above steps, as an example, a threshold value of influence degree is preset, and the value of the threshold value of influence degree can be reasonably set as needed. In this embodiment, the value of the threshold value of influence degree is set to 0.5. For each fluorescence peak influencing the fluorescence spectrum curve at the initial moment, it is determined whether the degree of influence of the overlapping peak on the fluorescence peak influencing the fluorescence peak is greater than the set threshold value of influence degree. At this time, there are two situations: If the degree of influence of the overlapping peak on the influencing fluorescence peak is greater than the set influence degree threshold, it means that the overlapping peak as a whole is a plant background fluorescence peak, then the absolute value of the difference between each characteristic indicator in the characteristic indicator sequence corresponding to the influencing fluorescence peak and the previous characteristic indicator is determined, and the ratio of the absolute value of the difference to the previous characteristic indicator is calculated, and the ratio is the decay rate of each characteristic indicator in the characteristic indicator sequence, and the average value of all decay rates corresponding to the characteristic indicator sequence is determined to obtain the average decay rate. Then, according to the average decay rate and the degree of influence of the overlapping peak on the influencing fluorescence peak, the characteristic index of the fluorescence peak in the fluorescence spectrum curve corresponding to the exhaustion moment of the fluorescence signal of the overlapping peak is corrected, so as to obtain the corrected characteristic index of the influencing fluorescence peak, and the corresponding calculation formula is: ; in, Indicates The corrected characteristic index affecting the fluorescence peak; Indicates a characteristic index of a corresponding fluorescence peak in the fluorescence spectrum curve corresponding to the moment when the fluorescence signal of the overlapping peak of the fluorescence peak is exhausted; Indicates The average decay rate of each characteristic indicator in the characteristic indicator sequence corresponding to the influencing fluorescence peak relative to the previous characteristic indicator; Indicates The degree to which the fluorescence peak is affected by the overlapping peaks.

[0064] In the above calculation formula, A characteristic index that affects the corresponding fluorescence peak in the fluorescence spectrum curve corresponding to the moment when the fluorescence signal of its overlapping peak is exhausted For this The real characteristic index that affects the fluorescence peak after attenuation. If there are multiple overlapping peaks, the fluorescence signal exhaustion time of the overlapping peak refers to the last fluorescence signal exhaustion time among the fluorescence signal exhaustion times of all overlapping peaks. Since the overlapping peaks are formed by the plant background fluorescence signal as a whole and decay too fast, it is necessary to deduct the cumulative interference of the plant background fluorescence signal by the average attenuation rate and the degree of influence of the overlapping peaks, so as to obtain the first A real characteristic indicator that affects the fluorescence peak.

[0065] If the degree of influence of the overlapping peak on the influencing fluorescence peak is not greater than the set influence degree threshold, it means that the overlapping peak is a pesticide fluorescence peak as a whole. Then, according to the degree of influence of the overlapping peak on the influencing fluorescence peak and the characteristic index of the overlapping peak on the influencing fluorescence peak in the fluorescence spectrum curve at the initial moment, the characteristic index of the influencing fluorescence peak in the fluorescence spectrum curve at the initial moment is corrected, so as to obtain the corrected characteristic index of the influencing fluorescence peak. The corresponding calculation formula is: ; in, Indicates The corrected characteristic index affecting the fluorescence peak; The fluorescence spectrum curve at the initial moment is represented by The characteristic index that affects the fluorescence peak; The fluorescence spectrum curve at the initial moment is represented by The average of the characteristic indicators of the overlapping peaks affecting the fluorescence peak; Indicates The degree to which the fluorescence peak is affected by the overlapping peaks.

[0066] In the above calculation formula, since the overlapping peak is the pesticide fluorescence peak as a whole, its decay time is relatively long, and the reference significance of the characteristic index affecting the fluorescence peak after the overlapping peak completely disappears is relatively small. Therefore, the characteristic index of each fluorescence peak affecting the fluorescence peak in the fluorescence spectrum curve at the initial moment is subtracted from the influence caused by the overlapping peak to obtain the final true characteristic index.

[0067] Step S600: measuring the pesticide residue concentration according to the corrected characteristic indexes of each of the pesticide fluorescence peaks in the fluorescence spectrum curve at the initial moment and the characteristic indexes of the remaining pesticide fluorescence peaks without overlapping peaks.

[0068] After obtaining the real characteristic indicators of each pesticide fluorescence peak in the fluorescence spectrum curve at the initial moment through the above steps, the accurate measurement of the pesticide residue concentration in the plant can be achieved based on these real characteristic indicators.

[0069] In this embodiment, the pesticide residue concentration is measured according to the corrected characteristic indexes of each of the pesticide fluorescence peaks in the fluorescence spectrum curve at the initial moment that affect the fluorescence peak and the characteristic indexes of the remaining pesticide fluorescence peaks without overlapping peaks, and the implementation steps include: The corrected characteristic index or characteristic index of the pesticide fluorescence peak in the fluorescence spectrum curve at the initial moment is used as the measurement characteristic index, and each measurement characteristic index is compared with the pre-calibrated characteristic index corresponding to the wavelength range of its pesticide fluorescence peak and the curve of the change with the pesticide concentration, so as to obtain the concentration of the pesticide component corresponding to the wavelength range of the pesticide fluorescence peak of each measurement characteristic index.

[0070] For the above steps, as an example, for each pesticide component, the relationship between the characteristic index of the pesticide fluorescence peak corresponding to the fluorescence spectrum curve of the pesticide component under standard conditions and the pesticide concentration is fitted to obtain a pre-calibrated characteristic index change curve with the pesticide concentration. When obtaining the change curve, the fluorescence spectrum curve of the pesticide sample with different known concentrations of the pesticide component can be obtained. The fluorescence spectrum curve refers to the fluorescence spectrum curve without time delay. Since each pesticide component corresponds to a specific band in the fluorescence spectrum curve, the pesticide fluorescence peak corresponding to the pesticide component in the fluorescence spectrum curve can be determined, and the characteristic index of the pesticide fluorescence peak of the pesticide component is obtained in the same way as the initial characteristic index of each fluorescence peak in the fluorescence spectrum curve in the above step S200. Different known concentrations are used as the horizontal coordinates, and the characteristic index corresponding to the different known concentrations is used as the vertical coordinate. The curve fitting of the relationship between the characteristic index and the pesticide concentration is performed, so as to obtain the calibrated characteristic index of the pesticide component with the change curve of the pesticide concentration. In this way, the calibrated characteristic index change curve of different types of pesticide components with the pesticide concentration can be obtained.

[0071] On this basis, when it is necessary to measure the pesticide residue concentration of the plant to be detected, the corrected characteristic index or characteristic index of the pesticide fluorescence peak in the fluorescence spectrum curve at the initial moment in the fluorescence spectrum data of the plant to be detected is used as a measurement characteristic index, and the measured characteristic index is compared with the pre-calibrated characteristic index corresponding to the wavelength range of the corresponding pesticide fluorescence peak and the change curve of the pesticide concentration, so as to obtain the concentration of the pesticide component corresponding to the measured characteristic index. In this way, the concentration of the pesticide component corresponding to each pesticide fluorescence peak in the fluorescence spectrum curve at the initial moment in the fluorescence spectrum data of the plant to be detected can be determined, and finally the accurate measurement of the pesticide residue concentration can be achieved.

[0072] Based on the same inventive concept, an embodiment of the present invention further provides a spectral detection device for the concentration of pesticide residues in plants, the device comprising: A spectral data acquisition module, used to acquire fluorescence spectral data of the plant to be detected, wherein the fluorescence spectral data includes a fluorescence spectral curve at an initial moment and fluorescence spectral curves at different delayed moments after the initial moment; An optical characteristic index acquisition module, used to determine the characteristic index of each fluorescence peak in the fluorescence spectrum curve according to the peak distribution of each fluorescence peak in the fluorescence spectrum curve; A pesticide expression degree acquisition module is used to determine the pesticide expression degree of each fluorescence peak in the fluorescence spectrum curve at the initial moment according to the change of the characteristic index of the same fluorescence peak in the different fluorescence spectrum curves and the change of the peak curve of the same fluorescence peak; An influence degree acquisition module is used to determine the pesticide fluorescence peak among the fluorescence peaks in the fluorescence spectrum curve at the initial moment according to the pesticide expression degree, and determine the various influence fluorescence peaks with overlapping peaks among all the pesticide fluorescence peaks, and determine the influence degree of the influence of the overlapping peak on the influence fluorescence peak according to the difference in the pesticide expression degree between the influence fluorescence peak and its overlapping peak, and the offset of the influence fluorescence peak in the fluorescence spectrum curve at different delay moments; A characteristic index correction module, for correcting the characteristic indexes of each fluorescence peak in the fluorescence spectrum curve at the initial moment based on the degree of influence of the overlapping peaks and the characteristic indexes corresponding to the fluorescence peaks and their overlapping peaks, to obtain corrected characteristic indexes; The pesticide residue concentration measurement module is used to measure the pesticide residue concentration according to the corrected characteristic indicators of each pesticide fluorescence peak in the fluorescence spectrum curve at the initial moment and the characteristic indicators of the remaining pesticide fluorescence peaks without overlapping peaks.

[0073] It should be noted that the device provided in the above embodiment is only illustrated by the division of the above functional modules. In actual applications, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the computer device can be divided into different functional modules to complete all or part of the functions described above.

[0074] Based on the same inventive concept, an embodiment of the present invention also provides a spectral detection system for the concentration of pesticide residues in plants, the system comprising: a memory, a processor, and a computer program stored in the memory and running on the processor, wherein when the processor executes the computer program, the system can execute any one of the spectral detection methods for the concentration of pesticide residues in plants introduced above.

[0075] The embodiment of the present invention can divide the system into functional modules according to the above method example. For example, each functional module can be corresponded to, or two or more functions can be integrated into one processing module. The above integrated module can be implemented in the form of hardware. It should be noted that the division of modules in this embodiment is schematic and is only a logical function division. There may be other division methods in actual implementation.

[0076] Based on the same inventive concept, an embodiment of the present invention also provides a computer program product, which includes: computer program code, when the computer program code runs on a computer, the computer executes any one of the spectral detection methods for pesticide residue concentration in plants introduced above.

[0077] Based on the same inventive concept, an embodiment of the present invention also provides a computer-readable storage medium, which stores a computer program code. When the computer program code runs on a computer, the computer executes any of the spectral detection methods for pesticide residue concentrations in plants introduced above.

[0078] It should be noted that the above-described embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit the same. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that the technical solutions described in the aforementioned embodiments may still be modified, or some of the technical features may be replaced by equivalents. Such modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present invention, and should all be included in the protection scope of the present invention.

Claims

1. A spectral detection method for pesticide residue concentration in plants, characterized in that: The following steps are involved: Acquiring fluorescence spectrum data of the plant to be detected, wherein the fluorescence spectrum data includes a fluorescence spectrum curve at an initial moment and fluorescence spectrum curves at different delayed moments after the initial moment; Determining characteristic indicators of each fluorescence peak in the fluorescence spectrum curve according to the peak distribution of each fluorescence peak in the fluorescence spectrum curve; Determining the pesticide representation degree of each fluorescence peak in the fluorescence spectrum curve at the initial moment according to the change of the characteristic index of the same fluorescence peak in the different fluorescence spectrum curves and the change of the peak curve of the same fluorescence peak; According to the pesticide expression degree, determine the pesticide fluorescence peak among the fluorescence peaks in the fluorescence spectrum curve at the initial moment, and determine the various influencing fluorescence peaks with overlapping peaks among all the pesticide fluorescence peaks, and determine the degree of influence of the influencing fluorescence peak by the overlapping peak according to the difference in the pesticide expression degree between the influencing fluorescence peak and its overlapping peak, and the offset of the influencing fluorescence peak in the fluorescence spectrum curve at different delay moments; Based on the degree of influence of the overlapping peaks and the characteristic indicators corresponding to the fluorescence peaks and the overlapping peaks, the characteristic indicators of each fluorescence peak influencing the fluorescence spectrum curve at the initial moment are corrected to obtain corrected characteristic indicators; The pesticide residue concentration is measured according to the corrected characteristic indexes of each of the pesticide fluorescence peaks in the fluorescence spectrum curve at the initial moment that affects the fluorescence peak and the characteristic indexes of the remaining pesticide fluorescence peaks without overlapping peaks.

2. The spectral detection method for pesticide residue concentration in plants according to claim 1, characterized in that: Determining characteristic indicators of each fluorescence peak in the fluorescence spectrum curve includes: For any fluorescence peak in the fluorescence spectrum curve, determining the peak concentration index of the fluorescence peak according to the average difference between each wavelength in the fluorescence peak and the peak wavelength, and the fluorescence intensity corresponding to each wavelength in the fluorescence peak; The characteristic index of the fluorescence peak is determined according to the peak concentration index of the fluorescence peak and the fluorescence intensity corresponding to the peak wavelength in the fluorescence peak, and the peak concentration index and the fluorescence intensity corresponding to the peak wavelength are both positively correlated with the characteristic index.

3. The spectral detection method for pesticide residue concentration in plants according to claim 1, characterized in that: Determining the pesticide representation degree of each fluorescence peak in the fluorescence spectrum curve at the initial moment comprises: Determine the fluorescence signal exhaustion time of each fluorescence peak in the fluorescence spectrum curve at the initial moment according to the change of each fluorescence peak in the fluorescence spectrum curve at the initial moment in the fluorescence spectrum curve at different delay moments, wherein the fluorescence signal exhaustion time corresponds to a delay moment; Determine the fluorescence signal attenuation time of each fluorescence peak in the fluorescence spectrum curve at the initial moment according to the time difference between the fluorescence signal exhaustion time of each fluorescence peak in the fluorescence spectrum curve at the initial moment and the initial moment; Determining the fluorescence signal change regularity index of each fluorescence peak in the fluorescence spectrum curve at the initial moment according to the change of the characteristic index of the same fluorescence peak in different fluorescence spectrum curves; According to the fluorescence signal attenuation time of each fluorescence peak in the fluorescence spectrum curve at the initial moment and the fluorescence signal change law index, the pesticide representation degree of each fluorescence peak in the fluorescence spectrum curve at the initial moment is determined, the fluorescence signal attenuation time is positively correlated with the pesticide representation degree, and the fluorescence signal change law index is negatively correlated with the pesticide representation degree.

4. The spectral detection method for pesticide residue concentration in plants according to claim 3, characterized in that: Determining the fluorescence signal decay time of each fluorescence peak in the fluorescence spectrum curve at the initial moment includes: Determine the average value of the time difference between the fluorescence signal exhaustion time of each fluorescence peak in the fluorescence spectrum curve at the initial time and the initial time, and obtain the time difference mean; Determine the ratio of the time difference between the fluorescence signal exhaustion time of each fluorescence peak in the fluorescence spectrum curve at the initial time and the initial time to the average of the time differences, so as to obtain the fluorescence signal attenuation time of each fluorescence peak in the fluorescence spectrum curve at the initial time.

5. The spectral detection method for pesticide residue concentration in plants according to claim 3, characterized in that: Determining the fluorescence signal change regularity index of each fluorescence peak in the fluorescence spectrum curve at the initial moment includes: Arrange the characteristic indices of the same fluorescence peak in different fluorescence spectrum curves ending at the time when the fluorescence signal is exhausted in time sequence, and obtain a corresponding characteristic indicator sequence of each fluorescence peak in the fluorescence spectrum curve at the initial time; Determine the difference of each characteristic index according to the difference between each two adjacent characteristic indexes in the characteristic index sequence; The average value of all the characteristic indicator differences corresponding to the characteristic indicator sequence is determined, so as to obtain the fluorescence signal change regularity index of each fluorescence peak in the fluorescence spectrum curve at the initial moment.

6. The spectral detection method for pesticide residue concentration in plants according to claim 3, characterized in that: Determining the degree to which the fluorescence peak is affected by the overlapping peaks comprises: Determine the average value of the difference in pesticide expression degree between the fluorescence-affecting peak and its overlapping peak to obtain the pesticide expression degree difference value of the fluorescence-affecting peak; Determine the peak shift index of the influencing fluorescence peak according to the position change of the influencing fluorescence peak and the peak value of the fluorescence peak corresponding to the fluorescence spectrum curve at different delay times ending at the time of exhaustion of the fluorescence signal; The degree of influence of the overlapping peaks on the fluorescence peak is determined according to the pesticide expression degree difference value and the peak deviation index affecting the fluorescence peak. Both the pesticide expression degree difference value and the peak deviation index are positively correlated with the degree of influence of the overlapping peaks.

7. The spectral detection method for pesticide residue concentration in plants according to claim 5, characterized in that: Correcting each characteristic index affecting the fluorescence peak in the fluorescence spectrum curve at the initial moment to obtain a corrected characteristic index includes: Determining whether the degree of influence of the overlapping peak on the fluorescence peak is greater than a set influence degree threshold; If the degree of influence of the overlapping peak on the influencing fluorescence peak is greater than a set influence degree threshold, then according to the difference between each two adjacent characteristic indicators in the characteristic indicator sequence corresponding to the influencing fluorescence peak and the degree of influence of the overlapping peak on the influencing fluorescence peak, the characteristic indicator of the corresponding fluorescence peak in the fluorescence spectrum curve corresponding to the fluorescence signal of the overlapping peak of the influencing fluorescence peak is corrected at the moment when the fluorescence signal of the overlapping peak is exhausted, so as to obtain the corrected characteristic indicator of the influencing fluorescence peak; If the degree of influence of the overlapping peak that affects the fluorescence peak is not greater than the set influence degree threshold, then the characteristic index of the fluorescence peak influencing the fluorescence peak in the fluorescence spectrum curve at the initial moment is corrected according to the degree of influence of the overlapping peak that affects the fluorescence peak and the characteristic index of the overlapping peak that affects the fluorescence peak in the fluorescence spectrum curve at the initial moment, so as to obtain the corrected characteristic index of the fluorescence peak.

8. The spectral detection method for pesticide residue concentration in plants according to claim 7, characterized in that: The characteristic index of the fluorescence peak in the fluorescence spectrum curve corresponding to the moment when the fluorescence signal of the fluorescence peak is exhausted is corrected to obtain the corrected characteristic index of the fluorescence peak. The corresponding calculation formula is: ； in, Indicates The corrected characteristic index affecting the fluorescence peak; Indicates a characteristic index of a corresponding fluorescence peak in the fluorescence spectrum curve corresponding to the moment when the fluorescence signal of the overlapping peak of the fluorescence peak is exhausted; Indicates The average decay rate of each characteristic indicator in the characteristic indicator sequence corresponding to the influencing fluorescence peak relative to the previous characteristic indicator; Indicates The degree to which the fluorescence peaks are affected by the overlapping peaks; The characteristic index affecting the fluorescence peak in the fluorescence spectrum curve at the initial moment is corrected to obtain the corrected characteristic index affecting the fluorescence peak. The corresponding calculation formula is: ； in, Indicates The corrected characteristic index affecting the fluorescence peak; The fluorescence spectrum curve at the initial moment is represented by The characteristic index that affects the fluorescence peak; The fluorescence spectrum curve at the initial moment is represented by The average of the characteristic indicators of the overlapping peaks affecting the fluorescence peak; Indicates The degree to which the fluorescence peak is affected by the overlapping peaks.

9. The spectral detection method for pesticide residue concentration in plants according to claim 1, characterized in that: Conduct pesticide residue concentration measurements, including: The corrected characteristic index or characteristic index of the pesticide fluorescence peak in the fluorescence spectrum curve at the initial moment is used as the measurement characteristic index, and each measurement characteristic index is compared with the pre-calibrated characteristic index corresponding to the wavelength range of its pesticide fluorescence peak and the curve of the change with the pesticide concentration, so as to obtain the concentration of the pesticide component corresponding to the wavelength range of the pesticide fluorescence peak of each measurement characteristic index.

10. A spectral detection system for pesticide residue concentration in plants, characterized in that: It comprises a memory, a processor and an executable computer program stored in the memory and run on the processor, wherein the processor executes the spectral detection method for the concentration of pesticide residues in plants as described in any one of claims 1 to 9 when executing the computer program.

Images