An online continuous detection system and method for feed ingredients

Abstract

The present invention discloses an online continuous detection system and method for feed ingredients, and belongs to the field of production detection technology. The present invention makes feed particles into powder and measures the humidity, determines the ionization temperature and adjusts the electric field strength according to the humidity, and then transports the ionized ions to the repulsion device through a transmission device, and sends the ions to the analysis device by applying a pulse voltage on the repulsion electrode. The present invention obtains the type and content of the components to be tested in the feed according to the data received by the analysis device, and calibrates the activation time of the analysis device according to the collection time of the matrix ions in the feed, thereby reducing the sampling drift of the system. The present invention adjusts the detection parameters in combination with the physical form and chemical composition of the feed particles to achieve continuous detection without stopping, is suitable for large-scale production, and meets the requirements of the workshop working environment.

Description

Technical Field

[0001] The present invention relates to the technical field of production detection, and in particular to an online continuous detection system and method for feed ingredients. Background Art

[0002] Mass spectrometry can be used to detect pesticide residues, heavy metals, antibiotics, and toxins in feed. Specifically, a liquid sample is first prepared, sample ions are ionized from the liquid sample, and the composition and content of the sample ions are predicted based on their mass-to-charge ratio and signal intensity. These methods require offline liquid sample preparation, making online continuous detection difficult and unsuitable for large-scale production. Chinese Patent Application Publication No. CN109813798A discloses a method for online continuous monitoring of hazardous chemicals or rapid identification of leaked substances. This method uses a reagent-assisted vacuum ultraviolet lamp as an ionization source and operates continuously via an ion mobility spectrometer, enabling online continuous monitoring of hazardous chemicals. Simultaneously, standard gases are used to calibrate the signal intensity of the gas sample being tested in real time, continuously monitoring changes in hazardous chemical concentrations. Because feed is a solid sample, ensuring product uniformity is difficult, making online continuous detection challenging. Furthermore, the feed production environment is relatively harsh, and detection clocks and sampling times can drift over time. To prevent data drift, existing detection methods require shutdown and debugging after each detection cycle. Therefore, further improvement of the existing technology is necessary. Summary of the Invention

[0003] In order to address the defects of the online continuous detection technology in the above-mentioned feed production process, the present invention proposes an online continuous detection system and method for feed ingredients. The ionization parameters of the ionization device are adjusted according to the physical properties of the feed to adapt to feed particles with different outputs. At the same time, the activation time of the analysis device is calibrated to reduce the downtime for calibration.

[0004] The technical solution of the present invention is achieved as follows:

[0005] An online continuous detection system for feed ingredients, comprising: a detection branch, a grinding device, a pre-detection device, a sample feeding device, an air supply device, an ionization device, a transmission device, a repulsion device, a migration device, an analysis device, a data processing device, a first calibration device, and a second calibration device, wherein:

[0006] The detection branch is configured to receive feed pellets from a conveyor belt;

[0007] The grinding device is configured to convert the feed particles into feed powder;

[0008] The pre-check device is configured to measure the current moisture content of the feed powder;

[0009] The sample feeding device is configured to provide feed powder to the first channel;

[0010] The gas supply device is configured to provide a gaseous solvent to the first channel;

[0011] The ionization device is configured to ionize sample ions from the feed powder and drive the ions into the second channel;

[0012] The transmission device is configured to modulate the sample ions into an ion beam and drive the ion beam into the third channel;

[0013] The repeller is configured to adjust the flight speed of the ion beam;

[0014] The migration device is configured to direct the ion beam into the analysis device;

[0015] The analyzing device is configured to receive matrix ions and analyte ions in the ion beam;

[0016] The data processing device is configured to detect the measured content of the matrix and the measured content and mass-to-charge ratio of the component to be measured;

[0017] The first calibration device is configured to calibrate an ionization parameter of the ionization device according to a current humidity of the feed powder;

[0018] The second calibration device is configured to calibrate the activation time of the analysis device according to the measured content of the matrix.

[0019] The present invention further comprises a first suction device and a second suction device, wherein the first suction device is configured to extract the remaining feed powder and gaseous solvent from the ionization device, and the second suction device is configured to extract the gaseous solvent from the transmission device and the migration device.

[0020] An online continuous detection method based on the online continuous detection system for feed ingredients comprises the following steps:

[0021] Step 1: A conveyor belt continuously transports feed pellets, the conveyor belt being connected to a detection branch, wherein a grinding device and a pre-detection device are sequentially arranged in the detection branch, and the feed pellets have a matrix and at least one component to be detected;

[0022] Step 2: The grinding device produces feed powder from the feed particles, the pre-detection device measures the current moisture content of the feed powder, and calibrates at least one ionization parameter of the ionization device according to the current moisture content;

[0023] Step 3: The sample delivery device sucks feed powder from the detection branch and supplies the feed powder to the first channel, and the gas supply device supplies gas solvent to the first channel;

[0024] Step 4: The ionization device in the first channel ionizes sample ions from the feed powder based on the ionization parameters, the sample ions enter the second channel, and the remaining feed powder and gas solvent return to the detection branch;

[0025] Step 5: The transmission device in the second channel modulates the sample ions into an ion beam and drives the ion beam into the third channel;

[0026] Step 6: Apply a pulse voltage to the repeller, and the matrix ions and the ions to be measured in the ion beam pass through the repeller and the migration device respectively and enter the analysis device;

[0027] Step 7: starting the analysis device at the starting time t0, the analysis device receives the matrix ions at the first collection time t1 and receives the component ions to be measured at the second collection time t2;

[0028] Step 8: Calculate the calibration acquisition time t3 based on the mass-to-charge ratio of the matrix ions, and then calibrate the activation time t4 based on the first acquisition time t1 and the calibration acquisition time t3;

[0029] Step 9: Calculate the mass-to-charge ratio of the component to be measured according to the second acquisition time t2, generate the measured content of the component to be measured according to the signal intensity at the second acquisition time t2, output the mass-to-charge ratio and measured content of the component to be measured, and return to step 2.

[0030] In the present invention, the matrix is ​​one or more of vitamins, proteins or carbohydrates, the components to be detected are one or more of heavy metals, toxins or pesticides, and the gaseous solvent is nitrogen.

[0031] In the present invention, in step 2, the ionization parameters include ionization temperature and electric field strength, the humidity difference between the current humidity and the calibrated humidity is calculated, the compensation temperature is calculated based on the humidity difference, and the ionization temperature is calculated based on the compensation temperature. If the ionization temperature is greater than the system linear temperature, the electric field strength of the ionization device is adjusted based on the ionization temperature and the pressure of the first channel.

[0032] In the present invention, in step 6, the matrix ions and the component ions to be detected in the ion beam pass through the migration device at the first flight velocity v1 and the second flight velocity v2 respectively.

[0033] In the present invention, in step 7, the signal intensity of the matrix is ​​determined according to the reference content of the matrix, and the moment with the signal intensity is found as the first acquisition moment t1.

[0034] In the present invention, in step 8, the sampling drift Δt is calculated according to the first acquisition time t1 and the calibration acquisition time t3, and the activation time t4 = t0 + Δt.

[0035] In the present invention, in step 9, the flight time of the component ion to be measured is determined according to the activation time t4 and the second acquisition time t2, and the mass-to-charge ratio and molar mass of the component ion to be measured are calculated according to the flight time of the component ion to be measured.

[0036] In the present invention, in step 9, a response function is generated based on the response ratios at multiple different calibration contents, and then the response ratio of the component to be measured at the second acquisition time t2 is calculated, and the actual measured content of the component to be measured is determined based on the response ratio and the response function.

[0037] The online continuous detection system and method for feed ingredients implemented in the present invention have the following beneficial effects: The present invention first measures the humidity of the feed powder and adjusts the ionization temperature of the ionization device according to the humidity, so that feeds with different production humidity levels can all be effectively ionized. To avoid system response delays caused by excessively high ionization temperatures, the present invention adjusts the electric field strength at high temperatures. The present invention calibrates the activation time of the analysis device based on the difference between the matrix's calibration acquisition time and the first acquisition time, reducing the system's sampling drift and avoiding the accumulation of errors in continuous detection. The present invention adjusts the detection parameters based on the physical form and chemical composition of the feed particles to achieve continuous detection without stopping, making it suitable for large-scale production and meeting the requirements of the workshop working environment. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 is a block diagram of an online continuous detection system for feed ingredients of the present invention;

[0039] Figure 2 Schematic diagram of the structure of the online continuous detection system of feed ingredients of the present invention;

[0040] Figure 3 Schematic diagram of the detection part of the online continuous detection system for feed ingredients of the present invention;

[0041] Figure 4 Flowchart of the online continuous detection method of the present invention;

[0042] Figure 5 is a schematic diagram of the ionization device of the present invention;

[0043] Figure 6 is a schematic diagram of a transmission device of the present invention;

[0044] Figure 7 is a schematic diagram of a repulsion device of the present invention;

[0045] Figure 8 is a schematic diagram of the migration device of the present invention;

[0046] Figure 9 is a mass spectrum of a preferred feed particle;

[0047] Figure 10 Schematic diagram of the clock period in which sampling drift occurs in the present invention;

[0048] Figure 11 Schematic diagram of the relationship between the various moments of the present invention;

[0049] Figure 12 is a response function diagram of the content and response ratio of the present invention;

[0050] Figure 13 Schematic diagram of various parameters in the repulsion device and migration device of the present invention.

[0051] Reference numerals in the accompanying drawings: 101 sample delivery port, 102 gas supply port, 103 vacuum ultraviolet krypton lamp, 104 transmission electrode, 105 driving electrode, 106 first aperture electrode, 107 sample delivery device, 108 first channel, 109 ionization device, 110 first suction device, 201 radio frequency transmission area, 202 second aperture electrode, 203 quadrupole, 204 electrostatic transmission area, 205 flat plate electrode, 206 slit, 207 transmission device, 208 The second channel, 209 the second suction device, 301 the repulsion electrode, 302 the repulsion zone, 303 the acceleration zone, 304 the field-free channel, 305 the first reflection zone, 306 the second reflection zone, 307 the reflection electrode, 308 the third channel, 309 the repulsion device, 310 the migration device, 311 the analysis device, 312 the data processing device, 401 the conveyor belt, 402 the detection branch, 403 the grinding device, 404 the pre-inspection device, 405 the air supply device. DETAILED DESCRIPTION

[0052] In order to more clearly understand the purpose, technical solutions and advantages of the present application, the present application is described and illustrated below in conjunction with the accompanying drawings and embodiments.

[0053] Existing continuous feed testing methods require high sample uniformity and periodic downtime for calibration, making them difficult to adapt to industrial continuous production. The present invention's online continuous feed ingredient testing system and method adjusts testing parameters based on the physical form and chemical composition of feed particles, enabling continuous testing without downtime. This system is suitable for large-scale production and meets the requirements of workshop working environments. Example 1

[0054] like Figures 1 to 3The online continuous detection system for feed ingredients of the present invention includes: a detection branch 402, a grinding device 403, a pre-detection device 404, a sample delivery device 107, an air supply device 405, an ionization device 109, a transmission device 207, a repulsion device 309, a migration device 310, an analysis device 311, a data processing device 312, a first calibration device, and a second calibration device. The detection branch 402 is configured to receive feed particles from a conveyor belt 401. The grinding device 403 is configured to convert the feed particles into feed powder. The pre-detection device 404 is configured to measure the current moisture content of the feed powder. The sample delivery device 107 is configured to supply feed powder to the first channel 108. The air supply device 405 is configured to supply a gaseous solvent to the first channel 108. The ionization device 109 is configured to ionize sample ions from the feed powder and drive the sample ions into the second channel 208. The transmission device 207 is configured to modulate the sample ions into an ion beam and drive the ion beam into the third channel 308. The repelling device 309 is configured to adjust the flight speed of the ion beam. The migration device 310 is configured to guide the matrix ions and the ions of the component to be measured through the field-free channel 304, so that the ion beam enters the analysis device. The analysis device 311 is configured to receive the matrix ions and the ions of the component to be measured in the ion beam. The data processing device 312 can be a computer and is configured to detect the measured content of the matrix and the measured content and mass-to-charge ratio of the component to be measured. The first calibration device is configured to calibrate the ionization parameters of the ionization device based on the current humidity of the feed powder. The second calibration device is configured to calibrate the activation time of the analysis device based on the measured content of the matrix. Finally, the mass spectrum and other data are displayed by the data display device. The system also includes a first suction device 110 and a second suction device 209. The first suction device 110 is configured to extract the remaining feed powder and gaseous solvent from the ionization device 109, and the second suction device 209 is configured to extract the gaseous solvent from the transmission device 207 and the migration device 310.

[0055] Reference Figure 2 The system first transports a small amount of feed particles on the conveyor belt to the grinding device 403 through the detection branch 402. The grinding device 403 grinds the feed particles into powder. At the same time, the pre-detection device 404 measures the current humidity of the feed powder and compares it with the calibration humidity. The ionization parameters in the ionization device 109 are calibrated through the first calibration device. Figure 3The sample delivery device draws feed powder from the grinding device 403, which then enters the first channel 108 through the sample delivery port. Simultaneously, the gas supply device 405 provides solvent gas to the first channel 108 from the gas supply port. The ionizer 109 in the first channel 108 transports the ionized sample ions to the second channel 208. The ion beam is then focused and modulated by the transmission device 207 in the second channel 208 and enters the third channel 308. The ions are then transported to the migration device 310 by the repelling device 309 in the third channel 308. The ions moving within the migration device 310 are reflected and enter the analysis device 311. The analysis device 311 receives these ions and transmits the data to the data processing device 312. The data processing device 312 analyzes and processes the data, creates a mass spectrum, and calculates the content of the component to be measured. To maintain the sensitivity of the instrument, the entire system must be maintained in a high vacuum environment to ensure that the ions have a sufficient free path and avoid collisions with neutral gas molecules during flight, which would affect the ion flight time. The present invention uses the first suction device 110 and the second suction device 209 to maintain a high vacuum environment in the system. At the same time, the present invention uses the second calibration device to calibrate the activation time of the analysis device 311.

[0056] The present invention adjusts the ionization temperature of the ionizer 109 based on the current humidity, ensuring effective ionization of feeds of varying production humidity. To prevent system response delays caused by excessively high ionization temperatures, the present invention adjusts the electric field strength at elevated temperatures. The present invention locates the corresponding first acquisition time t1 based on the signal intensity of the substrate. This first acquisition time t1 is then used to calibrate the activation time of the analysis device 311 using the time-of-flight calibration, mitigating the impact of sampling drift on the detection results. Example 2

[0057] like Figures 4 to 12 The online continuous detection method of the feed ingredient online continuous detection system of the present invention includes the following steps.

[0058] Step 1: A conveyor belt continuously transports feed pellets, which are connected to a detection branch. This detection branch is equipped with a grinding device and a pre-detection device. The feed pellets contain a matrix and at least one component to be detected. The matrix is ​​one or more of vitamins, proteins, or carbohydrates. The component to be detected is one or more of heavy metals, toxins, or pesticides. The gaseous solvent is nitrogen.

[0059] Step 2: The grinding device converts the feed particles into feed powder. The pre-detection device measures the current humidity of the feed powder and calibrates at least one ionization parameter of the ionization device based on the current humidity. Maintaining consistent humidity during the feed powder production process can affect the subsequent ionization process, so the relevant ionization parameters need to be adjusted based on the humidity to offset this effect. This embodiment calculates the difference between the current humidity and the calibration humidity, calculates a compensation temperature based on this humidity difference, and then calculates the ionization temperature based on the compensation temperature. If the ionization temperature exceeds the system linear temperature, the electric field strength of the ionization device 109 is adjusted based on the ionization temperature and the pressure of the first channel 108. For example, the calibration humidity is 12% and the system linear temperature is 50°C. If the powder humidity is too high, the ionization temperature is appropriately increased to facilitate water evaporation and reduce water vapor interference with subsequent component detection. However, when the ionization temperature is too high, the initial kinetic energy of the ionized ions is high. Furthermore, the pressure of the first channel 108 affects the collision frequency between ions, thereby affecting the ion diffusion rate. Therefore, the electric field strength of the ionization device 109 needs to be readjusted to reduce the negative effects of these two effects.

[0060] Specifically, the current humidity H1 of the feed powder is measured by the pre-detection device 404, and then the humidity difference H´=H1-H0 is calculated based on the calibrated humidity H0. The compensation coefficient k is set, and its value is, for example, k=0.1°C. The compensation temperature T´=kH´ is calculated based on the humidity difference H´ and the compensation coefficient k, and then the ionization temperature is adjusted to T1=T0+T´ based on the compensation temperature T´ and the calibrated ionization temperature T0. The system linear temperature T2 for stable operation of the system, if the ionization temperature T1 is greater than the system linear temperature T2, then the electric field strength is adjusted based on the difference between the ionization temperature T1 and the system linear temperature T2 and the pressure P1 of the first channel 108. The adjusted electric field strength is E´=E0+α(T1-T2)+βP1, where E0 is the calibrated electric field strength, which is approximately 6×10 6 V / m. α and β are temperature adjustment coefficient and pressure adjustment coefficient respectively, and their values ​​are, for example, α=-0.8×10 6 V / (m·℃), β=-0.2×10 5 V / (m·Pa).

[0061] Step 3: The sample delivery device draws feed powder from the detection branch and supplies it to the first channel, while the gas supply device supplies a gaseous solvent to the first channel. Feed powder enters the first channel 108 from the sample delivery port 101, and the gaseous solvent enters the first channel 108 from the gas supply port 102. When ionizing the powder, the powder needs to be dissolved in the gaseous solvent to ensure a more uniform diffusion of the powder in the first channel 108, facilitating the ionization operation. In this embodiment, nitrogen is used as the gaseous solvent because it is extremely stable and will not be ionized during the powder ionization process, thus not affecting the final detection results.

[0062] Step 4: The ionization device in the first channel ionizes sample ions from the feed powder based on the ionization parameters. The sample ions enter the second channel, and the remaining feed powder and gas solvent return to the detection branch. Figure 5 As shown, the ionization device 109 includes a vacuum ultraviolet krypton lamp 103 and an ionization zone. The vacuum ultraviolet krypton lamp 103 is mounted directly to the left of the ionization zone, with its light window facing the central aperture of the first aperture electrode 106, ensuring that the light beam passes through the entire ionization zone. The ionization zone is located between the vacuum ultraviolet krypton lamp 103 and the first aperture electrode 106. From left to right, a drive electrode 105 and three transmission electrodes 104 are arranged. A DC voltage is applied to the drive electrode 105 and the first aperture electrode 106, forming a uniform DC electric field along the central axis of the ionization zone. This electric field is the ionization field, which drives the ionized feed powder ions into the second channel 208.

[0063] To ensure the sensitivity of the instrument during the ionization process, it is necessary to increase the injection volume of the sample to be tested and the gaseous solvent, which will cause the air pressure in the first channel 108 to remain at a relatively high state. The interior of the migration device 310 needs to be in a high vacuum environment to ensure that the ions have a sufficient free path and do not collide with neutral gas molecules during flight, thereby affecting the ion flight time. Therefore, in order to ensure that the interior of the migration device 310 is in a high vacuum environment, the entire system needs to be evacuated. In this embodiment, a first suction device 110 is used to extract the remaining feed powder and gaseous solvent from the ionization device 109, and a second suction device 209 is used to extract the gaseous solvent from the transmission device and the migration device.

[0064] Step 5: The transmission device in the second channel modulates the sample ions into an ion beam and drives the ion beam into the third channel. Figure 6 As shown, the transmission device 207 is divided into two parts, a radio frequency transmission area 201 and an electrostatic transmission area 204 , by the first aperture electrode 106 , the second aperture electrode 202 , and the slit 206 .

[0065] There is a quadrupole in the RF transmission zone 201. The quadrupole 203 is composed of four parallel cylindrical electrodes arranged symmetrically. By applying RF voltages of opposite phases to two opposing cylindrical electrodes, a periodic RF electric field is formed inside the quadrupole 203. When the ion beam enters the RF transmission zone 201 from the ionization zone, it will gradually converge on the central axis of the quadrupole 203 in space under the action of the RF electric field, reducing the initial spatial divergence and initial energy divergence of the ion beam, and having a cooling and focusing effect on the ion beam. Then, under the action of the DC electric field formed by the voltage difference between the first aperture electrode 106 and the second aperture electrode 202, the ion beam is driven to the electrostatic transmission zone 204.

[0066] In the electrostatic transmission zone 204, there is a flat lens. The flat lens is an ion lens formed by an electrostatic field, and its effect on ions is similar to the effect of a convex lens on a light beam in an optical system. In this embodiment, the flat lens is composed of four rectangular flat electrodes 205, wherein the first and last electrodes are applied with the same voltage, and the middle two electrodes are applied with another identical voltage. The central potential of the two middle electrodes and the first and last electrodes form a two-dimensional single lens system. After the ion beam is cooled and focused by the quadrupole 203, its energy and angular divergence are relatively small. After passing through the electrostatic transmission zone 204, the flat lens further weakens the ion beam's vertical velocity and further reduces its divergence angle, compressing multiple ions into a nearly parallel ion beam with a rectangular cross-sectional area. Driven by the electric field formed by the voltage difference between the second aperture electrode 202 and the slit 206, the ion beam is driven into the third channel 308.

[0067] Step 6: Apply pulse voltage to the repelling device, and the matrix ions and the ions to be measured in the ion beam pass through the repelling device and the migration device respectively and enter the analysis device. There is a repelling device and a migration device in the third channel. Figure 7 As shown, the repelling device 309 includes a repelling region 302 and an accelerating region 303. The repelling region 302 includes a repelling electrode 301. When the ion beam passes through the slit 206 and enters the third channel 308, a pulse voltage is applied to the repelling electrode 301, forming an electric field between the repelling electrode and the electrode grid, which can repel the ion beam into the accelerating region 303. The voltage difference between the electrode grids then forms an electric field in the accelerating region 303, causing the matrix ions and the component ions to be detected to pass through the migration device 310 at a first flight velocity v1 and a second flight velocity v2, respectively.

[0068] like Figure 8 As shown, migration device 310 includes field-free channel 304, first reflection area 305, and second reflection area 306. Migration device 310 has a reflection electrode 307. Under the different voltages of electrode grid and reflection electrode 307, an electric field is formed in first reflection area 305 and second reflection area 306, and there is no electric field in field-free channel. When matrix ions and component ions to be measured enter migration device 310, because the electric field of electrode grid is 0, ions continue to maintain their original speed in field-free channel. When entering first reflection area 305 and second reflection area 306, ions will return to field-free channel 304 under the action of electric field. In this process, the speed of matrix ions and component ions to be measured in the horizontal direction is constant, and the speed in the vertical direction is first reduced to 0 and then returns to the original speed, but in opposite directions.

[0069] Step 7: Start the analysis device at the starting time t0, and the analysis device receives the matrix ions at the first collection time t1 and the component ions to be measured at the second collection time t2. The analysis device 311 is used to collect and amplify the ion signals and then transmit them to the data processing device 312. A mass spectrum is generated based on the intensity of the ion signals received from the starting time t0. In order to prevent the high-frequency signal from being reflected during the transmission process, it is necessary to set the impedance value of the load to match the internal impedance of the power supply. The data processing device 312 is started synchronously with the analysis device 311, receives the ion signal processed by the analysis device 311 and converts it into a pulse signal, and then compares the pulse signal with a preset threshold value to draw a mass spectrum with the flight time as the horizontal coordinate and the ion signal intensity of each mass-to-charge ratio as the vertical coordinate, as shown in FIG. Figure 9 shown.

[0070] In the present invention, the matrix accounts for a large proportion and has a stable content. The present invention determines the signal intensity of the matrix based on the relationship between the base content of the matrix and the signal intensity. The first acquisition time t1 is the basis for adjusting other time parameters to prevent other fragment ions from interfering with the determination of the acquisition time. The signal intensity of the matrix is ​​determined based on the base content of the matrix, and the moment with this signal intensity is found in the mass spectrum as the first acquisition time t1. The ions corresponding to the other multiple second acquisition times t2 in the mass spectrum are the component ions to be measured.

[0071] Step 8: Calculate the calibration acquisition time t3 based on the mass-to-charge ratio of the matrix ions, and then calibrate the activation time t4 based on the first acquisition time t1 and the calibration acquisition time t3. Figure 10 、 Figure 11 As shown, a detection cycle includes the sample delivery, ionization, and flight phases. In the continuous detection of the present invention, the set start time is equal to the initial activation time. However, as the operating time of the repulsion device 309 and the analysis device 311 increases, sampling drift occurs between adjacent detection cycles, causing a significant difference between the set start time and the activation time, affecting the flight time detection. To reduce the impact of sampling drift on the detection results in step 9, the activation time needs to be calibrated.

[0072] The theoretical flight time t of the matrix ions is calculated based on the mass-to-charge ratio of the matrix ions and the relationship between the mass-to-charge ratio and flight time of the ions in Example 3. The calibration acquisition time t3 = t0 + t is determined based on the starting time t0. The sampling drift Δt = t1 - t3 is calculated based on the time difference between the first acquisition time t1 and the calibration acquisition time t3. The activation time t4 = t0 + Δt is then calculated based on the starting time t0.

[0073] Step 9: Calculate the mass-to-charge ratio of the component to be measured according to the second acquisition time t2, generate the measured content of the component to be measured according to the signal intensity at the second acquisition time t2, output the mass-to-charge ratio and measured content of the component to be measured, and return to step 2.

[0074] The flight time t2-t4 of the component ion to be measured is obtained based on the difference between the second acquisition time t2 and the activation time t4 in the mass spectrum. The calibrated activation time t4 refers to the actual excitation time of the pulse voltage in the repulsion device 309. The mass-to-charge ratio of the component ion to be measured collected at the second acquisition time t2 is calculated based on the relationship between the mass-to-charge ratio of the ion and the ion flight time in Example 3, and then the molar mass is determined. Specifically, in the process of ionization of the feed component molecule in this embodiment, the feed component molecule will lose an electron and become an ion with a unit positive charge. The mass of the electron can be ignored, so the mass of the ion is equal to the molecular mass, and the molecular mass can be obtained by calculating the ion mass. Therefore, the mass-to-charge ratio of the component ion to be measured is multiplied by the charge number 1 to obtain the mass of the component ion to be measured. Since the mass of the ion is equal to the molecular mass, the molecular mass of the component to be measured can be obtained, and the molecular mass of different components is different. The obtained molecular mass of the component to be measured is then multiplied by the Avogadro constant to obtain the molar mass of the component molecule to be measured. The Avogadro constant N A Take 6.02×10 23 , and then determine the type of component to be tested based on the molar mass.

[0075] The response ratio η of a certain component refers to the ratio of the signal intensity σ corresponding to the component to the total signal intensity σ0 in the mass spectrum, that is, η=σ / σ0. Collect the response ratios under multiple different calibration contents, establish a coordinate system with the response ratio η as the horizontal coordinate and the content λ as the vertical coordinate, and mark the response ratio of the component and the corresponding calibration content in the coordinate system. These points are fitted into a smooth curve through the correlation fitting algorithm to obtain the relationship between the content λ and the response ratio η, that is, the response function λ=f(η). The response function is only related to the characteristics of the system itself. The present invention does not limit the correlation fitting algorithm. This embodiment uses the least squares method for fitting, and the fitting results are as follows. Figure 12 The signal intensity σ at the second acquisition time t2 is read from the mass spectrum and its ratio σ / σ0 to the total signal intensity σ0 is calculated to obtain the response ratio η of the component to be tested. Substituting this into the response function λ=f(η) yields the actual measured content of the corresponding component to be tested in the feed. Example 3

[0076] This example further discloses a preferred method for calculating the mass-to-charge ratio of the present invention.

[0077] The relationship between the length and field strength of each part of the repulsion device 309 and the migration device 310 and the starting position of the ion beam are as follows: Figure 13As shown in FIG. 1 . L1, L2, L3, L4, and L5 represent the lengths of the repulsion zone 302, the acceleration zone 303, the field-free channel 304, the first reflection zone 305, and the second reflection zone 306, respectively. E1, E2, E3, E4, and E5 represent the electric field strengths of the repulsion zone 302, the acceleration zone 303, the field-free channel 304, the first reflection zone 305, and the second reflection zone 306, respectively. Z is the distance between the starting position of the ion in the repulsion zone 302 and the electrode grid, and z is numerically the same as the distance from the slit 206 to the electrode grid. Since the mass of a single ion is small and the flight time is very short, the influence of gravity on ion motion can be ignored, and E3 is the field strength of the field-free channel 304, so E3=0.

[0078] Assume that t5, t6, t7, t8, and t9 are the times during which the ions move in the five fields during their ascent, the ion mass is m, and the charge carried is q. When the ions enter the third channel 308, their vertical velocity is first accelerated by the repulsion zone 302 and the acceleration zone 303. When the ions enter the field-free channel 304, they maintain a constant velocity. Then, under the action of the first reflection zone 305 and the second reflection zone 306, they are first decelerated to 0 and then accelerated in the opposite direction. When they enter the field-free channel 304 again, they maintain a constant velocity until they enter the analysis device 311. However, their horizontal velocity remains unchanged during the flight. Based on the ion motion relationship, the following relationship can be derived:

[0079] ; ; ; ; .

[0080] Since the longitudinal flight trajectories in the migration device 310 are equivalent in the upward and downward directions, the flight time t of the ions after entering the third channel 308 and flying to the analysis device 311 is 10 =t5+t6+2(t7+t8+t9). Substituting t5, t6, t7, t8, and t9 into the above expression, we can obtain the relationship between the mass-to-charge ratio of the ion and the flight time. The mass-to-charge ratio of the component ion to be measured can then be determined based on the flight time t2-t4.

[0081] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. An online continuous detection method using an online continuous detection system for feed ingredients, characterized in that: The online continuous detection system of feed ingredients comprises: a detection branch, a grinding device, a pre-inspection device, a sample delivery device, an air supply device, an ionization device, a transmission device, a repulsion device, a migration device, an analysis device, a data processing device, a first calibration device, and a second calibration device, wherein the detection branch is configured to receive feed particles from a conveyor belt; the grinding device is configured to make feed particles into feed powder; the pre-inspection device is configured to measure the current humidity of the feed powder; the sample delivery device is configured to provide feed powder to the first channel; the air supply device is configured to provide gas solvent to the first channel; the ionization device is configured to ionize a sample from the feed powder. ions and drive the ions into the second channel; the transmission device is configured to modulate the sample ions into an ion beam and drive the ion beam into the third channel; the repelling device is configured to adjust the flight speed of the ion beam; the migration device is configured to guide the ion beam into the analysis device; the analysis device is configured to receive the matrix ions and the ions of the component to be measured in the ion beam; the data processing device is configured to detect the measured content of the matrix and the measured content and mass-to-charge ratio of the component to be measured; the first calibration device is configured to calibrate the ionization parameters of the ionization device according to the current humidity of the feed powder; the second calibration device is configured to calibrate the activation time of the analysis device according to the measured content of the matrix, The online continuous detection method comprises the following steps: Step 1: A conveyor belt continuously transports feed particles, the conveyor belt is connected to a detection branch, a grinding device and a pre-detection device are sequentially arranged in the detection branch, and the feed particles have a matrix and at least one component to be detected; Step 2: The grinding device makes feed particles into feed powder, the pre-detection device measures the current humidity of the feed powder, and calibrates at least one ionization parameter of the ionization device according to the current humidity; Step 3: The sample delivery device inhales feed powder from the detection branch and provides the feed powder to the first channel, and the gas supply device provides gas solvent to the first channel; Step 4: the ionization device in the first channel ionizes sample ions from the feed powder based on the ionization parameters, the sample ions enter the second channel, and the remaining feed powder and gas solvent return to the detection branch; Step 5: The transmission device in the second channel modulates the sample ions into an ion beam and drives the ion beam into the third channel; Step 6: applying a pulse voltage to the repelling device, and the matrix ions and the component ions to be measured in the ion beam pass through the repelling device and the migration device respectively and enter the analysis device; Step 7: starting the analysis device at the start time t0, the analysis device receives the matrix ions at the first collection time t1 and receives the component ions to be measured at the second collection time t2; Step 8: Calculate the calibration acquisition time t3 according to the mass-to-charge ratio of the matrix ions, and then calibrate the activation time t4 according to the first acquisition time t1 and the calibration acquisition time t3; Step 9: Calculate the mass-to-charge ratio of the component ion to be measured according to the second acquisition time t2, generate the measured content of the component to be measured according to the signal intensity at the second acquisition time t2, output the mass-to-charge ratio and the measured content of the component to be measured, and return to step 2.

2. The online continuous detection method according to claim 1, characterized in that: The matrix is ​​one or more of vitamins, proteins or carbohydrates, the components to be detected are one or more of heavy metals, toxins or pesticides, and the gas solvent is nitrogen.

3. The online continuous detection method according to claim 1, characterized in that: In step 2, the ionization parameters include ionization temperature and electric field strength. The humidity difference between the current humidity and the calibrated humidity is calculated, the compensation temperature is calculated according to the humidity difference, and the ionization temperature is calculated according to the compensation temperature. If the ionization temperature is greater than the system linear temperature, the electric field strength of the ionization device is adjusted according to the ionization temperature and the pressure of the first channel.

4. The online continuous detection method according to claim 1, characterized in that: In step 6, the matrix ions and the component ions to be detected in the ion beam pass through the migration device at the first flight speed v1 and the second flight speed v2 respectively.

5. The online continuous detection method according to claim 1, characterized in that: In step 7, the signal intensity of the matrix is ​​determined according to the reference content of the matrix, and a time with the signal intensity is found as the first acquisition time t1.

6. The online continuous detection method according to claim 5, characterized in that: In step 8, the sampling drift Δt is calculated according to the first acquisition time t1 and the calibration acquisition time t3, and the activation time t4 = t0 + Δt.

7. The online continuous detection method according to claim 6, characterized in that: In step 9, the flight time of the component ion to be measured is determined according to the activation time t4 and the second acquisition time t2, and the mass-to-charge ratio and molar mass of the component ion to be measured are calculated according to the flight time of the component ion to be measured.

8. The online continuous detection method according to claim 7, characterized in that: In step 9, a response function is generated according to the response ratios at multiple different calibrated contents, and then the response ratio of the component to be measured at the second acquisition time t2 is calculated, and the actual measured content of the component to be measured is determined according to the response ratio and the response function.

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