Liquid sample detection method and system based on terahertz technology

Abstract

The present invention relates to the field of terahertz detection technology, and discloses a liquid sample detection method and system based on terahertz technology, including using a preset operating frequency band of a terahertz detection device to detect a liquid sample to obtain the number of components of the liquid sample in the preset operating frequency band, and setting a low frequency band, and using the terahertz detection device to detect the liquid sample again at the low frequency band to obtain the number of components of the liquid sample in the low frequency band. The present invention can clearly identify component characteristics and avoid water masking effects by setting preset operating frequency bands and low frequency bands, and realize complementary advantages by combining the high resolution of the high frequency band and the low interference characteristics of the low frequency band; for samples with high water content, the target threshold is ignored by dynamically adjusting the interference degree to avoid low similarity components being misjudged as non-existent due to water masking, thereby improving detection sensitivity.

Description

Technical Field

[0001] The present invention relates to the field of terahertz detection technology, and in particular to a liquid sample detection method and system based on terahertz technology. Background Art

[0002] The liquid sample detection method based on terahertz technology is a technology that uses terahertz waves (frequency range 0.1-10THz, between microwaves and infrared) to interact with liquid samples and realize detection by analyzing their transmission, reflection or absorption characteristics. Its technical advantages are that it does not need to contact or destroy the sample, can detect trace components, and a single measurement is usually completed in milliseconds. It can directly detect through plastic, ceramics and other packaging materials.

[0003] The detection of liquid samples based on terahertz technology does not require the liquid samples to be removed from the container. The internal components of liquid samples can be directly detected in containers such as plastic bottles and glass test tubes, which is safe, convenient and fast. However, there are also challenges and difficulties in actual detection: the strong absorption of terahertz waves by water may mask the signals of other components, especially in the 1THz frequency band. The absorption of water is dominated by small molecule vibrations and rapid relaxation, which may cause errors in the detection of components in liquid samples by terahertz detection equipment. Although thin-layer sample cells are currently used to limit liquid samples to micron-level thickness in order to significantly reduce the total absorption path length of water to retain effective signals, this method is costly and prone to contact and damage to liquid samples.

[0004] To this end, the present invention provides a liquid sample detection method and system based on terahertz technology. Summary of the invention

[0005] In view of the problems existing in the above-mentioned prior art, the purpose of the present invention is to provide a liquid sample detection method and system based on terahertz technology, so as to reduce the interference and masking degree of water in the liquid sample on other component signals without destroying the liquid sample, thereby obtaining more accurate liquid sample component detection results.

[0006] In order to achieve the above-mentioned purpose, the present invention provides the following technical solution: a liquid sample detection method based on terahertz technology, comprising the following steps:

[0007] Using a preset operating frequency band of a terahertz detection device to detect the liquid sample to obtain the number of components of the liquid sample in the preset operating frequency band, and setting a low frequency band, using the terahertz detection device to detect the liquid sample again in the low frequency band to obtain the number of components of the liquid sample in the low frequency band;

[0008] The number of components in the preset operating frequency band is compared with the number of components in the low frequency band. When the number of components in the low frequency band is less than or equal to the number of components in the preset operating frequency band, it indicates that all components in the sample can be obtained when the liquid sample is detected using the preset operating frequency band, and the detection result based on the preset operating frequency band is used as the final result; when the number of components in the low frequency band is greater than the number of components in the preset operating frequency band, it indicates that under the preset operating frequency band, the absorption of terahertz waves by water in the liquid sample masks the signals of some components, resulting in the loss of the detection result, and the low frequency band is divided into multiple frequency band ranges for detection;

[0009] According to the detection results within each frequency band, the frequency band with the highest similarity in the terahertz fingerprint library of the extra component is obtained, and the frequency band is set as a suitable frequency band;

[0010] Set an ideal similarity threshold, compare the extra components in the suitable frequency band with the similarity in the terahertz fingerprint library and the ideal similarity threshold. If the obtained similarity is greater than or equal to the ideal similarity, the detection result of the suitable frequency band will be used as the final result; if the obtained similarity is less than the ideal similarity, it means that the detection result of the liquid sample in the low frequency band cannot clearly obtain the detection signal of the extra components, and execute the secondary detection plan in the preset operating frequency band;

[0011] The secondary detection scheme in the preset operating frequency band includes the detection personnel shaking the container carrying the liquid sample and re-detecting the liquid sample at the preset operating frequency band. If the result of re-detecting the liquid sample at the preset operating frequency band still cannot detect the target component, the detection result based on the suitable frequency band will be used as the final result; if the result of re-detecting the liquid sample at the preset operating frequency band detects the target component, the similarity between the current detection result and the terahertz fingerprint library is obtained, and the similarity is compared with the similarity of the detection result obtained in the suitable frequency band, and the one with greater similarity is used as the final result according to the comparison result.

[0012] In some embodiments, when the number of components in a preset operating frequency band is compared with the number of components in a low frequency band, when the number of components in the low frequency band is less than or equal to the number of components in the preset operating frequency band, the detection result based on the preset operating frequency band will be used as the final result; when the number of components in the low frequency band is greater than the number of components in the preset operating frequency band, it indicates that under the preset operating frequency band, the absorption of terahertz waves by water in the liquid sample masks the signals of some components, resulting in the loss of the detection results.

[0013] In some embodiments, the specific method of dividing the low frequency band into multiple frequency band ranges and detecting them is: dividing the frequency band range of the low frequency band into n frequency band ranges, and using a terahertz detection device to detect the excess components in the liquid sample in each frequency band range, and the frequency band width of each frequency band range does not exceed 0.1.

[0014] In some embodiments, when the number of components in the low frequency band is greater than the number of components in the preset operating frequency band, it indicates that the water in the liquid sample has obvious absorption interference on the terahertz wave, and also reflects that the water content in the liquid sample is high. At this time, the ignore target threshold will be used to replace the preset terahertz fingerprint library trusted similarity threshold.

[0015] In some embodiments, the setting method of ignoring the target threshold is: subtracting the number of components M detected in the low frequency band from the number of components N detected in the preset operating frequency band to obtain the interference degree D=MN, and then obtaining the ignoring target threshold T by using the preset terahertz fingerprint library trusted similarity threshold T0 and the interference degree D. ignore =T0-k×D, where k is the interference sensitivity coefficient, which indicates the adjustment amplitude of each additional component to the threshold, and sets the minimum tolerance threshold T min , in order to prevent misjudgment caused by too low a threshold, and combined with the minimum tolerance threshold T min Get the target ignoring threshold T ignore =max(T0-k×D,T min ).

[0016] The present invention also provides the following technical solution: a liquid sample detection system based on terahertz technology, comprising a dual detection module, a low frequency division module, a frequency band matching module and a result feedback module;

[0017] The dual detection module includes using a preset operating frequency band of a terahertz detection device to detect a liquid sample to obtain the number of components of the liquid sample in the preset operating frequency band, and setting a low frequency band, and using the terahertz detection device to detect the liquid sample again in the low frequency band to obtain the number of components of the liquid sample in the low frequency band;

[0018] The low frequency division module includes comparing the number of components in the preset operating frequency band with the number of components in the low frequency band, and when the number of components in the low frequency band is greater than the number of components in the preset operating frequency band, dividing the low frequency band into a plurality of frequency band ranges and detecting them;

[0019] The frequency band matching module includes obtaining the frequency band range with the highest similarity in the terahertz fingerprint library of the extra component according to the detection results within each frequency band range, and setting the frequency band range to a suitable frequency band;

[0020] The result feedback module includes setting an ideal similarity threshold, comparing the similarity of the extra components in the suitable frequency band with the similarity in the terahertz fingerprint library and the ideal similarity threshold, and making corresponding responses according to the comparison results.

[0021] The present invention further provides a computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, and the computer program is executed by a processor to implement the above-mentioned liquid sample detection method based on terahertz technology.

[0022] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0023] Firstly, the present invention can clearly identify the characteristics of components and avoid the water masking effect by setting the preset operating frequency band and the low frequency band, combining the high resolution of the high frequency band and the low interference characteristics of the low frequency band, thereby achieving complementary advantages.

[0024] Secondly, the present invention divides the low frequency band into multiple frequency band ranges and matches them with the terahertz fingerprint library to find the frequency band with the most significant component absorption characteristics, thereby improving the credibility of the detection results.

[0025] Thirdly, for samples with high water content, the present invention dynamically adjusts the target ignoring threshold by the interference degree (the difference in the number of low-frequency components and the preset frequency band components), thereby avoiding the misjudgment of low-similarity components as non-existent due to water masking, thereby improving the detection sensitivity.

[0026] Fourthly, the design of the present invention is suitable for direct detection in the original state of the liquid, avoiding chemical reagent treatment or drying steps, retaining sample integrity, and is suitable for scenarios such as medical, food, and security inspections that require non-destructive testing, solving the limitations of traditional terahertz technology in detecting high-water-content liquids. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 It is a schematic diagram of the flow of the liquid sample detection method based on terahertz technology of the present invention;

[0028] Figure 2 It is a module schematic diagram of the liquid sample detection system based on terahertz technology of the present invention. DETAILED DESCRIPTION

[0029] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0030] It is to be understood that the term "one" should be understood as "at least one" or "one or more", that is, in one embodiment, the number of an element may be one, while in another embodiment, the number of the element may be multiple, and the term "one" should not be understood as a limitation on the quantity.

[0031] See also Figure 1 The present invention provides a liquid sample detection method based on terahertz technology, the method comprising the following steps:

[0032] The liquid sample is detected using the preset operating frequency band of the terahertz detection device to obtain the number of components of the liquid sample in the preset operating frequency band, and a low frequency band is set, and the liquid sample is detected again using the terahertz detection device in the low frequency band to obtain the number of components of the liquid sample in the low frequency band; in the low frequency band, the frequency band used by the terahertz detection device will be lower than the preset operating frequency band. As a higher frequency band, the preset operating frequency band has stronger penetration and higher resolution, and can more clearly detect the component characteristics in the liquid sample, and in the low frequency band, the absorption coefficient of water is lower, so that the terahertz detection device can more sensitively detect the components in the water, so as to effectively reduce the masking of the detection signal by water. For example: for the detection of ethanol, methanol and amino acid components in liquids, these components have outstanding absorption characteristics in the frequency band of 1-1.5THz, and also have certain absorption characteristics in the frequency band below 1.5THz. The preset operating frequency band can be set to 1-1.5THz, and the number of component types of the liquid sample detected by the terahertz detection equipment in the preset operating frequency band is 2. The low frequency band is set to 0.1-1THz. This is because the absorption coefficient of water will be significantly reduced at frequencies below 1THz. The number of component types of the liquid sample detected by the terahertz detection equipment in the low frequency band is set to 3.

[0033] Then, the number of components in the preset operating frequency band is compared with the number of components in the low frequency band. When the number of components in the low frequency band is less than or equal to the number of components in the preset operating frequency band, it indicates that all components in the sample can be obtained when the liquid sample is tested using the preset operating frequency band, while some components may not be obvious enough due to their low absorption coefficient in the low frequency band. The test personnel can use the test result of the preset operating frequency band as the final result; and when the number of components in the low frequency band is greater than the number of components in the preset operating frequency band, it indicates that under the preset operating frequency band, the absorption of terahertz waves by water in the liquid sample masks the signals of some components, resulting in the loss of the test results. At this time, the low frequency band should be divided into multiple frequency band ranges, and each frequency band should be tested according to the frequency band range. The detection results within the segment range are used to obtain the frequency band range with the highest similarity with the terahertz fingerprint library of the extra component, and the frequency band range is set to a suitable frequency band. Specifically, the frequency band range is equally divided into n frequency band ranges according to the frequency band range of the low frequency band, and the terahertz detection equipment is used to detect the extra components in the liquid sample in each frequency band range, and the frequency band width of each frequency band range (that is, the difference between the upper limit and the lower limit) does not exceed 0.1 to ensure fine segmentation; using the terahertz fingerprint library to compare the similarity of the detection results is a very effective way. The terahertz fingerprint library contains a large number of absorption characteristic spectra of known molecules in different frequency bands. By comparing the detected sample spectral features with the existing molecular spectra in the library, the similarity between the sample and the standard library spectrum can be quantified.

[0034] Combined with the above example, since the number of component types of the liquid sample detected in the low frequency band is 3, which is greater than the number of component types of the liquid sample detected in the preset operating frequency band, 2, it can be determined that the absorption of terahertz waves by water in the liquid sample causes the loss of 1 component detection result in the preset operating frequency band. Then the low frequency band (0.1-1THz) can be divided into 9 frequency bands, and the liquid sample can be tested in each frequency band. The specific test results can be referred to the following table:

[0035] Frequency range 0.1-0.2 0.2-0.3 0.3-0.4 0.4-0.5 0.5-0.6 0.6-0.7 0.7-0.8 0.8-0.9 0.9-1.0 Similarity results / / / 45% 65% 75% 60% 35% /

[0036] According to the above test results, the highest similarity with the terahertz fingerprint library is 75%, and the corresponding frequency band is 0.6-0.7THz. Therefore, the frequency band is set to a suitable frequency band, and the test result of the suitable frequency band is used as the final result of the component;

[0037] At the same time, an ideal similarity threshold is set to compare the size of the extra components in the suitable frequency band with the similarity in the terahertz fingerprint library and the ideal similarity threshold, and respond accordingly based on the comparison result. The significance of setting an ideal similarity threshold is that when the detection result of the suitable frequency band is used as the final result, since the suitable frequency band is a frequency band within the low frequency band, although the low frequency band has less interference, the signal in the low frequency band is weak and the resolution is relatively poor. Therefore, the detection result under the suitable frequency band may lack sufficient clarity and cannot provide sufficient information about the components in the liquid.

[0038] Specifically, after detecting the extra components in the suitable frequency band, its spectral characteristics are matched with the terahertz fingerprint library, and the obtained similarity is compared with the ideal similarity threshold. If the obtained similarity is greater than or equal to the ideal similarity, it means that the detection signal result of the extra components in the suitable frequency band is clear enough and can relatively completely present the absorption characteristics of the components. The detection result based on the suitable frequency band will be used as the final result. If the obtained similarity is less than the ideal similarity, it means that the detection result of the liquid sample in the low frequency band cannot clearly obtain the detection signal of the extra components. At this time, a secondary detection plan should be executed in the preset operating frequency band.

[0039] The secondary detection scheme in the preset operating frequency band specifically includes: the detection personnel shake the container carrying the liquid sample, and re-detect the liquid sample in the preset operating frequency band. This is because in the initial detection, the absorption signal of water in the liquid sample is strong, which masks the signal of the target component. After shaking the container, the arrangement of water molecules will change in the container, making the liquid sample more evenly mixed. The redistribution of the dissolved substances inside may make the absorption signal of the target component in the preset operating frequency band more obvious, so that the detection personnel can detect the target component in the preset operating frequency band;

[0040] After the above steps, the terahertz detection device is used to detect the liquid sample. If the target component cannot be detected after the re-test of the liquid sample under the preset operating frequency band, the test result of the suitable frequency band will be used as the final result; if the target component is detected after the re-test of the liquid sample under the preset operating frequency band, the similarity between the current test result and the terahertz fingerprint library is obtained, and the similarity is compared with the similarity of the test result obtained in the suitable frequency band, and the one with greater similarity is used as the final result according to the comparison result. After the above steps, if the test result of the suitable frequency band is relatively vague, you can try to change the result again, so as to obtain a clearer result. For example, the ideal similarity threshold can be set to 80%. In combination with the above embodiment, the similarity result under the suitable frequency band (0.6-0.7THz) is 75%, which means that the detection signal result under the suitable frequency band is fuzzy and not ideal. Therefore, it is necessary to execute a secondary detection scheme in the preset operating frequency band. After setting the execution scheme, the target component is detected by re-detecting the liquid sample under the preset operating frequency band, and its similarity with the terahertz fingerprint library is 78%. The result is compared with the similarity result of 75% under the suitable frequency band, and the result of re-detecting the liquid sample under the preset operating frequency band should be selected as the final result;

[0041] In addition, an ignore target threshold can also be set. After obtaining the similarity between the components in the liquid sample and the terahertz fingerprint library, the terahertz detection device will judge whether the detection signal is credible based on the degree of similarity, that is, whether the component exists in the liquid sample. For example, if the preset credible similarity threshold for the terahertz fingerprint library is 70%, then all detection results with a similarity lower than 70% will be ignored, and the terahertz detection device will judge that the component does not exist in the liquid sample. However, when detecting a liquid sample with a high water content, since water has a masking effect on other components in the liquid sample, after the terahertz detection device obtains the similarity between the spectral characteristics of the components in the water and the terahertz fingerprint library, the similarity will be reduced due to the masking of water. This results in that when the water content of the liquid sample is high, water will reduce the similarity score of the components in the liquid and cause the components to be omitted in the detection. In order to avoid the above problems, a dynamically adjustable ignore target threshold should be set to replace the preset credible similarity threshold for the terahertz fingerprint library.

[0042] Furthermore, the setting method of ignoring the target threshold is that when the number of components in the low frequency band is greater than the number of components in the preset operating frequency band, it indicates that the water in the liquid sample has obvious absorption interference on the terahertz wave, and also reflects that the water content in the liquid sample is high. At this time, the ignoring target threshold will be used to replace the preset terahertz fingerprint library trusted similarity threshold. The number of components detected in the preset operating frequency band Difference to get interference degree , and then through the preset credible similarity threshold of the terahertz fingerprint library The degree of interference Get the ignore target threshold ,in, is the interference sensitivity coefficient, which indicates the adjustment amplitude of each additional component to the threshold, and sets the minimum tolerance threshold To prevent misjudgment due to too low a threshold, combined with the minimum tolerance threshold Get the ignore target threshold , for example, to set the number of components detected in the preset operating frequency band 3, the number of components detected in the low frequency band If it is 2, the interference degree Set to 1 to set the preset credible similarity threshold for the terahertz fingerprint library The interference sensitivity coefficient is 70%. 5%, we can get the target ignoring threshold Therefore, when detecting liquid samples, the components whose spectral features are 65% similar to the terahertz fingerprint library are retained and identified as corresponding components, while the results whose spectral features are less than 65% similar to the terahertz fingerprint library are ignored. Through this scheme, the requirements for the similarity between the spectral feature detection results and the fingerprint library can be relaxed when there is strong water interference in the liquid sample, so as to balance the detection sensitivity and accuracy.

[0043] In general, the present invention aims to design a liquid sample detection method based on terahertz technology, the purpose of which is to reduce the interference of water in the liquid sample on the detection results of other component signals, so that the liquid sample can obtain more accurate detection results without being damaged. Specifically, the liquid sample is first detected through a preset operating frequency band to obtain the number of components in the initial liquid sample, and then the liquid sample is detected again through a low frequency band with a lower absorption coefficient of water. By setting a low frequency band (0.1-1THz), the absorption interference of water molecules on terahertz waves is reduced by utilizing the characteristic of low absorption coefficient of water in the low frequency band, so as to more sensitively detect the signals of other components in the water, and the high resolution of the preset operating frequency band (1-1.5THz) and the low frequency band can be combined. The low-interference characteristic can not only clearly identify the characteristics of the components, but also avoid the water masking effect, thereby achieving complementary advantages; and the low-frequency band is divided into multiple frequency band ranges and matched with the terahertz fingerprint library, so as to find the frequency band with the most significant component absorption characteristics, thereby improving the credibility of the detection results; and for samples with high water content, the target threshold is dynamically adjusted by the interference degree (the difference in the number of low-frequency and preset frequency band components) to avoid low-similarity components being misjudged as non-existent due to water masking, thereby improving the detection sensitivity. The design of the present invention is suitable for direct detection in the original state of the liquid, avoiding chemical reagent treatment or drying steps, retaining the integrity of the sample, and is suitable for medical, food, security inspection and other scenarios requiring non-destructive testing, which solves the limitations of traditional terahertz technology in the detection of high-water-content liquids.

[0044] See also Figure 2 , the present invention provides a liquid sample detection system based on terahertz technology, including a dual detection module, a low frequency division module, a frequency band matching module and a result feedback module;

[0045] The dual detection module includes using a preset operating frequency band of a terahertz detection device to detect a liquid sample to obtain the number of components of the liquid sample in the preset operating frequency band, and setting a low frequency band, and using the terahertz detection device to detect the liquid sample again in the low frequency band to obtain the number of components of the liquid sample in the low frequency band;

[0046] The low-frequency division module includes comparing the number of components in the preset operating frequency band with the number of components in the low frequency band, and when the number of components in the low frequency band is greater than the number of components in the preset operating frequency band, dividing the low frequency band into multiple frequency band ranges, and using a terahertz detection device to detect the excess components in the liquid sample in each frequency band range;

[0047] The frequency band matching module includes obtaining the frequency band range with the highest similarity in the terahertz fingerprint library of the extra component according to the detection results within each frequency band range, and setting the frequency band range to a suitable frequency band;

[0048] The result feedback module includes setting an ideal similarity threshold, comparing the similarity of the extra components in the suitable frequency band with the similarity in the terahertz fingerprint library and the ideal similarity threshold, and making corresponding responses according to the comparison results.

[0049] The embodiments disclosed in the present invention, the process described above with reference to the flowchart can be implemented as a computer software program. The embodiments disclosed in the present invention include a computer program product, which includes a computer program carried on a computer-readable medium, and the computer program contains a program code for executing the method shown in the flowchart. In such an embodiment, the computer program can be downloaded and installed from the network through the communication part, and / or installed from a removable medium. When the computer program is executed by the central processing unit, the above functions defined in the method of the present application are executed. It should be noted that the computer-readable medium mentioned above in the present application can be a computer-readable signal medium or a computer-readable storage medium or any combination of the above two. The computer-readable storage medium can be, for example, but not limited to, a system, device or device of an electrical, magnetic, optical, electromagnetic, infrared segment, or semiconductor, or any combination of the above. More specific examples of computer-readable storage media can include, but are not limited to: an electrical connection with one or more wire segments, a portable computer disk, a hard disk, a random access memory, a read-only memory, an erasable programmable read-only memory, an optical fiber, a portable compact disk read-only memory, an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present application, a computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, apparatus, or device. In the present application, a computer-readable signal medium may include a data signal propagated in a baseband or as part of a carrier wave, which carries a computer-readable program code. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium, which may send, propagate, or transmit a program for use by or in combination with an instruction execution system, apparatus, or device. The program code contained on the computer-readable medium may be transmitted using any suitable medium, including but not limited to: wireless segments, wire segments, optical cables, RF, etc., or any suitable combination of the above.

[0050] The flow chart and block diagram in the accompanying drawings illustrate the possible architecture, function and operation of the system, method and computer program product according to various embodiments of the present invention. In this regard, each square box in the flow chart or block diagram can represent a module, a program segment or a part of a code, and the module, the program segment or a part of the code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the square box can also occur in a sequence different from that marked in the accompanying drawings. For example, two square boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each square box in the block diagram and / or flow chart, and the combination of the square boxes in the block diagram and / or flow chart can be implemented with a dedicated hardware-based system that performs the specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0051] Those skilled in the art should understand that the above description is only a specific implementation mode of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be covered by the protection scope of the present application.

Claims

1. A liquid sample detection method based on terahertz technology, characterized in that: The steps include: Using a preset operating frequency band of a terahertz detection device to detect the liquid sample to obtain the number of components of the liquid sample in the preset operating frequency band, and setting a low frequency band, using the terahertz detection device to detect the liquid sample again in the low frequency band to obtain the number of components of the liquid sample in the low frequency band; The number of components in the preset operating frequency band is compared with the number of components in the low frequency band. When the number of components in the low frequency band is less than or equal to the number of components in the preset operating frequency band, it indicates that all components in the sample can be obtained when the liquid sample is detected using the preset operating frequency band, and the detection result based on the preset operating frequency band is used as the final result; when the number of components in the low frequency band is greater than the number of components in the preset operating frequency band, it indicates that under the preset operating frequency band, the absorption of terahertz waves by water in the liquid sample masks the signals of some components, resulting in the loss of the detection result, and the low frequency band is divided into multiple frequency band ranges for detection; According to the detection results within each frequency band, the frequency band with the highest similarity in the terahertz fingerprint library of the extra component is obtained, and the frequency band is set as a suitable frequency band; Set the ideal similarity threshold, compare the extra components in the suitable frequency band with the similarity in the terahertz fingerprint library and the ideal similarity threshold. If the obtained similarity is greater than or equal to the ideal similarity, the detection result of the suitable frequency band will be used as the final result; If the obtained similarity is less than the ideal similarity, it means that the detection result of the liquid sample in the low frequency band cannot clearly obtain the detection signal of the additional component, and the secondary detection scheme is executed in the preset operating frequency band; The secondary detection scheme at the preset operating frequency band includes the detection personnel shaking the container carrying the liquid sample and re-detecting the liquid sample at the preset operating frequency band. If the result of the re-detection of the liquid sample at the preset operating frequency band still cannot detect the target component, the detection result of the appropriate frequency band will be used as the final result; If the target component is detected in the retest of the liquid sample under the preset operating frequency band, the similarity between this test result and the terahertz fingerprint library is obtained, and the similarity is compared with the similarity of the test result obtained in the appropriate frequency band, and the one with greater similarity is taken as the final result based on the comparison result.

2. The liquid sample detection method based on terahertz technology according to claim 1, characterized in that: When comparing the number of components in the preset operating frequency band with the number of components in the low frequency band, when the number of components in the low frequency band is less than or equal to the number of components in the preset operating frequency band, the detection result of the preset operating frequency band will be used as the final result; when the number of components in the low frequency band is greater than the number of components in the preset operating frequency band, it indicates that under the preset operating frequency band, the absorption of terahertz waves by water in the liquid sample masks the signals of some components, resulting in the loss of detection results.

3. The liquid sample detection method based on terahertz technology according to claim 1, characterized in that: The specific method of dividing the low frequency band into multiple frequency band ranges and detecting them is: dividing the frequency band range of the low frequency band into n frequency band ranges, and using terahertz detection equipment to detect the extra components in the liquid sample in each frequency band range, and the frequency band width of each frequency band range does not exceed 0.

1.

4. The liquid sample detection method based on terahertz technology according to claim 1, characterized in that: When the number of components in the low frequency band is greater than the number of components in the preset operating frequency band, it indicates that the water in the liquid sample has obvious absorption interference on the terahertz wave, and also reflects that the water content in the liquid sample is high. At this time, the ignore target threshold will be used to replace the preset terahertz fingerprint library trusted similarity threshold.

5. The liquid sample detection method based on terahertz technology according to claim 4, characterized in that: The method for setting the target ignoring threshold is as follows: the number of components M detected in the low frequency band is subtracted from the number of components N detected in the preset operating frequency band to obtain the interference degree D=MN, and then the target ignoring threshold T is obtained by the preset terahertz fingerprint library trusted similarity threshold T0 and the interference degree D. ignore =T0-k×D, where k is the interference sensitivity coefficient, which indicates the adjustment amplitude of each additional component to the threshold, and sets the minimum tolerance threshold T min , in order to prevent misjudgment caused by too low a threshold, and combined with the minimum tolerance threshold T min Get the target ignoring threshold T ignore =max(T0-k×D,T min ).

6. A liquid sample detection system based on terahertz technology, characterized in that: The liquid sample detection method based on terahertz technology according to any one of claims 1 to 5 comprises a dual detection module, a low frequency division module, a frequency band matching module and a result feedback module; The dual detection module includes using a preset operating frequency band of a terahertz detection device to detect a liquid sample to obtain the number of components of the liquid sample in the preset operating frequency band, and setting a low frequency band, and using the terahertz detection device to detect the liquid sample again in the low frequency band to obtain the number of components of the liquid sample in the low frequency band; The low frequency division module includes comparing the number of components in the preset operating frequency band with the number of components in the low frequency band, and when the number of components in the low frequency band is greater than the number of components in the preset operating frequency band, dividing the low frequency band into a plurality of frequency band ranges and detecting them; The frequency band matching module includes obtaining the frequency band range with the highest similarity in the terahertz fingerprint library of the extra component according to the detection results within each frequency band range, and setting the frequency band range to a suitable frequency band; The result feedback module includes setting an ideal similarity threshold, comparing the similarity of the extra components in the suitable frequency band with the similarity in the terahertz fingerprint library and the ideal similarity threshold, and making corresponding responses according to the comparison results.

7. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores a computer program, and the computer program is executed by a processor to implement the liquid sample detection method based on terahertz technology as described in any one of claims 1 to 5.

Images