Tobacco shred moisture detection method and system based on thermal analysis and infrared combination method

Abstract

The invention discloses a tobacco shred moisture detection method and system based on a thermal analysis infrared combined method, and relates to the technical field of tobacco detection.The method comprises the steps that under the set gradient temperature rise test condition, a tobacco shred sample is tested through the thermal analysis infrared combined method, and a test curve is obtained; according to the test curve, determining heat release substances and heat absorption and release conditions in different temperature intervals, and determining a gradient temperature rise scheme according to the heat release substances and the heat absorption and release conditions; determining moisture contents and microstructure diagrams of the tobacco shred samples under different gradient heating schemes, comparing the moisture contents of the tobacco shred samples with standard moisture contents, judging whether national standard errors are met or not, and evaluating the quality of the dried tobacco shreds on the microstructure diagrams, so as to optimize the gradient heating schemes; and under the optimized gradient heating scheme, detecting the to-be-detected tobacco shreds to obtain the moisture content. The tobacco shred moisture detection efficiency is improved, the detection precision is ensured, and meanwhile, the tobacco shred drying quality can be controlled through auxiliary analysis based on the microstructure chart.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of tobacco detection, in particular to a cut tobacco moisture detection method and system based on thermal analysis infrared combined method. BACKGROUND

[0002] The statements in this section merely provide background information related to the present application and do not necessarily constitute the prior art.

[0003] In cigarette production, the overall uniformity and sensory characteristics of cut tobacco are mainly evaluated by cut tobacco moisture, in addition to which, cut tobacco moisture also affects various physical parameters, processing and production, storage and transportation, etc. of cigarettes, and is a process index highly concerned by the tobacco industry. Therefore, having precise and rapid detection capability of cut tobacco moisture is the core competitiveness of cigarette production enterprises.

[0004] At present, the existing cut tobacco moisture detection method mainly uses oven detection, which is accurate and can represent the total moisture content of cut tobacco. However, the cycle detection period of this detection method is relatively long, about 2 hours.

[0005] At present, the moisture detection method on the production line mainly uses online moisture meter detection, which has the advantage of real-time collection, but is greatly affected by the environment and the storage and transportation mode of cut tobacco, resulting in unstable moisture detection results, and is not universal for all cut tobacco products or semi-finished products.

[0006] In addition, microwave detection is also one of the common moisture detection methods, but due to changes in environmental temperature and humidity or detection samples, the microwave detection instrument needs to be verified by oven method frequently. When the verification time conflicts with production needs, the detection sample quantity is large and the time is urgent, which cannot meet the analysis and verification needs of production enterprises. Moreover, in order to avoid defects in cut tobacco quality caused by the pursuit of detection efficiency improvement, the heating rate must be strictly controlled and the cut tobacco crushing must be reduced. Therefore, there is an urgent need for a cut tobacco moisture detection method with high detection precision, strong universality, short detection period and constant detection quality. SUMMARY

[0007] In order to solve the above problems, the present application provides a cut tobacco moisture detection method and system based on thermal analysis infrared combined method, which improves the detection efficiency of cut tobacco moisture and ensures the detection precision, and the auxiliary analysis based on the microstructure diagram helps to control the cut tobacco quality.

[0008] In order to achieve the above purpose, the present application adopts the following technical solutions: In a first aspect, the present application provides a cut tobacco moisture detection method based on thermal analysis infrared combined method, comprising: under the set gradient temperature test conditions, the cut tobacco sample is tested by thermal analysis infrared combined method to obtain a test curve; According to the test curve, the heat release substance and heat absorption and release in different temperature intervals are determined, and the gradient heating scheme is determined; The moisture content and microstructure of the cut tobacco sample under different gradient heating schemes are determined, the moisture content of the cut tobacco sample is compared with the standard moisture content, whether the national standard error is met is judged, and the quality of the dried cut tobacco is evaluated according to the microstructure, so that the gradient heating scheme is optimized. Under the optimized gradient heating scheme, the moisture content of the cut tobacco to be tested is detected.

[0009] As an optional implementation, the gradient heating test conditions include: a temperature rising rate of 5 ℃ / min from room temperature to a holding temperature; constant temperature holding at the holding temperature for a set time; and a temperature rising rate of 5 ℃ / min from the holding temperature to the highest temperature.

[0010] As an optional implementation, the process of determining the gradient heating scheme includes: The heat release substance and heat absorption and release in the mass rapid loss stage, the remaining mass platform period during constant temperature holding, and the high temperature stage are determined. In the mass rapid loss stage, if the organic components escaping in the designed temperature interval exceed the set threshold or pyrolysis exothermic peak appears, the end temperature in the interval is too high, and needs to be adjusted again. In the remaining mass platform period, if the mass loss in the constant temperature interval exceeds the set threshold and pyrolysis exothermic phenomenon appears, one or more detection temperature points are selected below the holding temperature, otherwise, the detection temperature points are selected according to the mass loss change in the third stage of the temperature rising interval. In the high temperature stage, the pyrolysis substance release and heat absorption and release at the inflection point temperature are observed, if the organic component release occurs before the inflection point temperature, the selected detection temperature point is less than the inflection point temperature, otherwise, the detection temperature point is selected after the inflection point temperature, and no pyrolysis substance release occurs at the selected detection temperature point.

[0011] As an optional implementation, under different gradient heating schemes, the moisture content of the cut tobacco sample is detected by the oven method, the upper limit of the oven method test temperature does not exceed the minimum temperature of cut tobacco thermal degradation, the minimum temperature of cut tobacco thermal degradation is obtained from the mass loss, infrared spectrum and heat absorption and release curve, and there is an obvious endothermic peak in the temperature rising interval range, and no exothermic peak appears.

[0012] As an optional implementation, the process of evaluating the quality of the dried cut tobacco according to the microstructure includes observing the microstructure change of the dried cut tobacco, the wrinkles of the cut tobacco after drying are guaranteed to be stretched but without cracks, if the number and width of the cracks appearing in the wrinkles after drying according to a certain gradient heating scheme are greater than the set threshold, the scheme is discarded.

[0013] As an alternative embodiment, the moisture content of the tobacco sample is compared with the standard moisture content to determine whether the average value and single deviation meet the requirements of the national standard detection error.

[0014] In a second aspect, the present application provides a tobacco moisture detection system based on thermal analysis infrared combined method, comprising: The test module is configured to perform thermal analysis infrared combined method test on the tobacco sample under the set gradient temperature test condition to obtain a test curve. The scheme determination module is configured to determine the heat release substances and heat absorption and release conditions in different temperature intervals according to the test curve, and determine the gradient temperature scheme accordingly. The optimization module is configured to determine the moisture content and microstructure diagram of the tobacco sample under different gradient temperature schemes, compare the moisture content of the tobacco sample with the standard moisture content to determine whether the national standard error is met, and evaluate the quality of the post-cured tobacco based on the microstructure diagram, so as to optimize the gradient temperature scheme. The detection module is configured to detect the moisture content of the tobacco to be tested under the optimized gradient temperature scheme.

[0015] In a third aspect, the present application provides an electronic device comprising a memory and a processor, and computer instructions stored in the memory and running on the processor, wherein when the computer instructions are run by the processor, the method of the first aspect is completed.

[0016] In a fourth aspect, the present application provides a computer readable storage medium for storing computer instructions, wherein when the computer instructions are executed by a processor, the method of the first aspect is completed.

[0017] In a fifth aspect, the present application provides a computer program product comprising a computer program, wherein when the computer program is executed by a processor, the method of the first aspect is completed.

[0018] Compared with the prior art, the present application has the following advantages: The present application provides a tobacco moisture detection method and system based on thermal analysis infrared combined method, which uses thermal analysis infrared combined method to detect the release of substances during tobacco pyrolysis in real time, accurately controls the tobacco heat release state at any temperature point, and quickly determines the temperature program for tobacco moisture detection. The production of tobacco products or semi-finished products is selected as the experimental object, the detection time is shortened to the shortest on the basis of continuously optimizing the temperature program and controlling the cut tobacco quality through microstructure analysis, and the detection efficiency is improved. The present application uses thermal analysis technology and instrument combined technology with precise temperature control for tobacco moisture detection, improves the efficiency of tobacco moisture detection, ensures the detection accuracy, and the auxiliary analysis based on the microstructure diagram helps to control the quality of cut tobacco.

[0019] The application provides a cut tobacco moisture detection method and system based on a thermal analysis infrared combined method, adopts microscopic image analysis to assist thermal analysis-infrared combined technology to explore cut tobacco pyrolysis material release, heat absorption and release and microscopic structure change conditions in a temperature rising process, and optimizes and determines a programmed temperature rising scheme through an oven drying method, the rapid detection method shows good result reproducibility and accuracy, improves cut tobacco moisture quality detection efficiency and cut tobacco drying quality.

[0020] Advantages of the additional aspects of the application will be partially given in the following description, partially become obvious from the following description, or be known by the practice of the application. BRIEF DESCRIPTION OF DRAWINGS

[0021] In order to more clearly illustrate the technical solutions in the embodiments of the application or the prior art, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description only are the embodiments of the application, and for those skilled in the art, other drawings can be obtained without creative labor on the basis of the provided drawings.

[0022] Figure 1 A cut tobacco moisture detection method flowchart based on a thermal analysis infrared combined method is provided for the application example 1. Figure 2 A thermal gravimetric infrared combined thermal gravimetric diagram is provided for the application example 1. Figure 3 Infrared spectrograms at different weight loss times are provided for the application example 1. Figure 4 A thermal gravimetric infrared combined spectrogram is provided for the application example 1. Figure 5 A thermal gravimetric infrared combined release material release intensity two-dimensional diagram is provided for the application example 1. Figure 6 An infrared three-dimensional diagram of a thermal gravimetric infrared sample is provided for the application example 1. Figure 7 Sample microscopic structure images under different temperature rising programs are provided for the application example 1. DETAILED DESCRIPTION

[0023] The application will be further described below in combination with the drawings and examples.

[0024] It should be pointed out that the following detailed description is exemplary and aims to provide further description of the application. Unless otherwise specified, all technical and scientific terms used in this paper have the same meaning as generally understood by those skilled in the art to which the application belongs.

[0025] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that the terms "include" and "comprise" and any variations are intended to cover non-exclusive inclusions. For example, a process, method, system, product or device that includes a series of steps or units is not necessarily limited to those steps or units that are clearly listed, but may include other steps or units that are not clearly listed or inherent to these processes, methods, products or devices.

[0026] In the absence of conflict, the embodiments of the present invention and the features thereof may be combined with each other.

[0027] Example 1 In view of the difficulties of the existing tobacco moisture detection method, such as long cycle, low detection efficiency and poor universality, this embodiment provides a tobacco moisture detection method based on thermal analysis and infrared coupling method. Figure 1 As shown, it can meet the detection needs of industrial production.

[0028] The specific steps include: Under the set gradient temperature test conditions, the tobacco samples were tested by thermal analysis and infrared spectroscopy to obtain the test curve; According to the test curve, determine the heat release substances and heat absorption and release conditions in different temperature ranges, and use this to determine the gradient heating plan; Determine the moisture content and microstructure of tobacco samples under different gradient heating schemes, compare the moisture content of tobacco samples with the standard moisture content to determine whether it meets the national standard error, and evaluate the quality of the tobacco after drying based on the microstructure diagram, so as to optimize the gradient heating scheme; Under the optimized gradient heating scheme, the moisture content of the tobacco to be tested is detected.

[0029] The method of this embodiment is described in detail below.

[0030] S1: Collection of thermal analysis infrared combined method TGA-DSC-FTIR test curves of tobacco samples, such as Figures 2-4 As shown, specifically including: All tobacco samples were tested by thermal analysis and infrared spectroscopy under the same temperature and humidity environment; A three-stage gradient heating curve was designed according to the test requirements: (1) heating from room temperature (25 °C or 30 °C) to the holding temperature at a heating rate of 5 °C / min; (2) maintaining a constant temperature at the holding temperature for a set time; (3) heating from the holding temperature to the highest temperature at a heating rate of 5 °C / min.

[0031] Other test conditions are set as follows: test atmosphere: air; carrier gas flow rate: 40 mL / min; interface transmission temperature: 170 ℃ (variable); gas cell temperature: 170 ℃, and infrared spectrum frequency range: 600-4500 cm -1 .

[0032] As an alternative embodiment, the room temperature is set to 25-30 ℃, preferably 25 ℃, 27 ℃ or 30 ℃, but is not limited thereto, and can be set by those skilled in the art according to actual detection requirements.

[0033] As an alternative embodiment, the holding temperature is set to 100-130 ℃, preferably 100 ℃, but is not limited thereto, and can be set by those skilled in the art according to actual detection requirements.

[0034] As an alternative embodiment, the holding temperature is kept constant for 30-45 min, preferably 45 min, but is not limited thereto, and can be set by those skilled in the art according to actual detection requirements.

[0035] As an alternative embodiment, the maximum temperature is set to 200-300 ℃, preferably 200 ℃, 250 ℃ or 300 ℃, but is not limited thereto, and can be set by those skilled in the art according to actual detection requirements.

[0036] As an alternative embodiment, the sample mainly involves: cut tobacco products or semi-finished products.

[0037] S2: Screening of the gradient temperature rising scheme for cut tobacco moisture detection.

[0038] Different cut tobacco products have three main change stages under the temperature rising test conditions.

[0039] The first stage is a rapid mass loss stage, mainly the release of moisture or volatile components; The second stage is a remaining mass platform stage during the constant temperature holding; The third stage is a high temperature stage, and part of the cut tobacco begins to have thermal degradation, and the residual mass decreases obviously.

[0040] Based on this, the heat release substances and heat absorption and release conditions in different temperature intervals are determined based on the TGA-DSC-FTIR test curve, and the gradient temperature rising scheme is screened by monitoring the mass loss change of cut tobacco under different temperature rising test conditions; specifically: (1) The temperature interval, release substance and heat absorption and release condition of the rapid mass loss stage are determined; (2) The temperature interval, substance release and heat absorption and release condition of the remaining mass platform stage are determined; (3) Clear the release of matter and heat absorption and release of high temperature stage.

[0041] In this embodiment, as shown in Figures 5-6 With the aid of infrared spectrum and heat absorption and release spectrum of heat release substance, it is preliminarily distinguished whether there is water evaporation or organic matter thermal decomposition weight loss in different temperature rising or holding stages, and the gradient temperature rising scheme of the oven method experiment is optimized and determined based on this.

[0042] The optimization of the gradient temperature rising scheme should comply with the following principles: (1) In the first stage of rapid mass loss, in addition to the escape of water and volatile components, there is a significant endothermic peak, and no exothermic peak or a large amount of organic component substance cracking escape. If a large amount of organic component escapes or a thermal decomposition exothermic peak appears in the designed temperature range, it is proved that the end point temperature of the temperature rising range is too high, and the temperature or time needs to be adjusted.

[0043] (2) In the second stage, whether there is rapid mass loss in the holding interval, if rapid mass loss and significant thermal decomposition exothermic phenomenon appear in the holding interval, it is proved that a large amount of organic component is pyrolyzed and escapes, then the detection temperature point is selected below the holding temperature, and the holding time needs to be optimized. Select one or more different temperature points, otherwise, the mass loss change in the third temperature rising interval can be observed.

[0044] (3) In the third stage, the release of pyrolysis substance and heat absorption and release at the inflection point temperature are mainly observed. If the organic component releases before the inflection point temperature, the selected temperature is less than the inflection point temperature, and one or more temperature points are selected and the holding time is optimized. Otherwise, the temperature point can be selected after the inflection point temperature, but it is ensured that there is no release of pyrolysis substance at the temperature point.

[0045] (4) Steps (2) and (3) can be repeated to set the gradient temperature rising program.

[0046] S3: Under different gradient temperature rising schemes, the moisture content and microstructure of the cut tobacco sample are detected by the oven method, the detection time is calculated by summarizing the moisture detection results of the cut tobacco under different temperature rising schemes, and the microstructure is observed.

[0047] The highest upper limit of the oven method test temperature does not exceed the minimum temperature of the cut tobacco thermal degradation, and the minimum temperature of the cut tobacco thermal degradation is obtained by comprehensive analysis of the mass loss, infrared spectrum and heat absorption and release curve. There is a significant endothermic peak in the temperature rising curve range, and no exothermic peak appears.

[0048] S4: The national standard oven method detection experiment is carried out for comparison, and the moisture content of the cut tobacco sample is detected in the same test environment as the thermal analysis infrared combined method, The current cut tobacco product moisture detection method includes: (1) The temperature of the blast oven is set to 100°C. Open the sample box cover and place the sample box and the sample box cover together in the middle layer of the oven. Blast dry for 30 minutes. Cover the sample box and take it out and place it in a desiccator. After cooling to room temperature, weigh it to the nearest 0.001g and record it as m0.

[0049] (2) Place the sample box immediately in the desiccator. Mix the sample evenly, take 5±0.3g and place it in a sample box of known weight, cover it and weigh it to the nearest 0.001g, record it as M; (3) Place the prepared sample in the dryer immediately, repeat the above steps to prepare two samples, mark and record them; open the lid of the sample box and place it in the middle layer of the oven for forced air drying. The density of the sample box should be no less than 1 / 120cm 2 .

[0050] (4) When the temperature rises and remains at (100 ± 2)°C, start timing. When the time reaches 2 h, remove the sample box with the lid closed and quickly place it in a desiccator. After cooling to room temperature, weigh it to the nearest 0.001 g, recording it as m. The formula for calculating the moisture content of cut tobacco is: X = [(Mm) / (M-m0)] × 100%.

[0051] S5: Optimization of tobacco moisture detection method.

[0052] According to the determined heating program and test duration, the national standard oven method test experiment and the microstructure test experiment are carried out simultaneously for comparison, and the experimental results are summarized and compared; first, in terms of data, according to the error requirements of the national standard for testing the moisture content of tobacco, the moisture content of the tobacco sample is compared with the standard moisture content tested by the national standard method to determine whether the national standard error is met, that is, to compare whether the test average value and the single deviation meet the requirements of the national standard test error.

[0053] In terms of microstructure, the microstructure of tobacco samples under different heating programs was analyzed to observe the changes in the microstructure of the dried tobacco, such as Figure 7 As shown, after drying, tobacco wrinkles are guaranteed to be stretched but crack-free. However, if the microstructure after a certain drying temperature program shows a significant number of cracks (excluding leaf pores) in the wrinkles, and if the number and width of the cracks exceed the set threshold, the detection temperature program method is discarded. Avoid the pursuit of time efficiency. Rapid heating rates can lead to excessive dehydration of tobacco, which in actual production results in a high amount of raw material breakage and waste of raw materials in production and processing.

[0054] Therefore, the optimal gradient heating scheme is selected by comprehensively considering the moisture detection data and the quality of the dried tobacco. The optimal gradient heating scheme is a drying heating program that has the highest detection efficiency while ensuring the optimal quality of the dried tobacco. Microstructure analysis is used to screen the samples dried by the heating program, so as to ensure that the dried tobacco has a good expansion without cracks and reduce the production of broken tobacco. Finally, the selected optimal detection method is tested in different experimental environments for a long time to verify the rationality of the detection method.

[0055] Embodiment 2 The embodiment provides a moisture detection system for tobacco based on a thermal analysis infrared combined method, which comprises: A test module configured to perform thermal analysis infrared combined method test on the tobacco sample under the set gradient heating test condition to obtain a test curve; A scheme determination module configured to determine the heat release substances and the heat absorption and release in different temperature intervals according to the test curve, and determine the gradient heating scheme based on the same; An optimization module configured to determine the moisture content and the microstructure of the tobacco sample under different gradient heating schemes, compare the moisture content of the tobacco sample with the standard moisture content, determine whether the national standard error is met, and evaluate the quality of the dried tobacco based on the microstructure, so as to optimize the gradient heating scheme; A detection module configured to detect the moisture content of the tobacco to be tested under the optimized gradient heating scheme.

[0056] It should be noted that the above modules correspond to the steps described in Embodiment 1, and the above modules have the same examples and application scenarios as the corresponding steps, but are not limited to the content disclosed in Embodiment 1. It should be noted that the above modules as part of the system can be executed in a computer system such as a set of computer executable instructions.

[0057] In more embodiments, the following are also provided: An electronic device comprising a memory and a processor, and computer instructions stored in the memory and running on the processor, when the computer instructions are run by the processor, the method described in Embodiment 1 is completed. For brevity, it will not be repeated here.

[0058] It should be understood that in the embodiment, the processor can be a central processing unit CPU, and the processor can also be other general-purpose processors, digital signal processors DSPs, application-specific integrated circuits ASICs, ready-to-program gate arrays FPGA or other programmable logic devices, discrete gates or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor, etc.

[0059] The memory can include read-only memory and random access memory, and provide instructions and data to the processor, a portion of the memory can also include non-volatile random access memory. For example, the memory can also store device type information.

[0060] A computer readable storage medium for storing computer instructions, which are executed by a processor to complete the method described in embodiment 1.

[0061] The method in embodiment 1 can be directly embodied as a hardware processor to complete, or be completed by a combination of hardware and software modules in the processor. The software module can be located in a storage medium mature in the art such as random access memory, flash memory, read-only memory, programmable read-only memory, or electrically erasable programmable memory, register, etc. The storage medium is located in the memory, and the processor reads the information in the memory to complete the steps of the above method in combination with the hardware. To avoid repetition, it will not be described in detail here.

[0062] A computer program product comprising a computer program, which, when executed by a processor, implements the method described in embodiment 1.

[0063] The present application also provides at least one computer program product tangibly stored on a non-transitory computer readable storage medium. The computer program product includes computer executable instructions, such as those included in program modules, executed by devices at a destination real or virtual processor to perform processes / methods as described above. Generally, program modules include routines, programs, libraries, objects, classes, components, data structures, etc. that perform particular tasks or implement particular abstract data types. In various embodiments, the functionality of program modules can be combined or split between program modules as desired. Machine executable instructions for program modules can be executed within a local or distributed device. In a distributed device, program modules can be located in local and remote storage media.

[0064] Computer program code for carrying out operations of the present application can be written in one or more programming languages. These computer program codes can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus, so that the program codes cause the functions / operations specified in the flowcharts and / or block diagrams to be performed when the computer or other programmable data processing apparatus executes the program codes. The program codes can be executed entirely on the computer, partially on the computer, as a standalone software package, partially on the computer and partially on a remote computer, or entirely on a remote computer or server.

[0065] In the context of the present application, the computer program code or related data can be carried by any suitable carrier to enable the device, apparatus or processor to perform the various processes and operations described above. Examples of carriers include signals, computer readable media, and the like. Examples of signals can include electrical, optical, radio, sound or other forms of propagated signals, such as carrier waves, infrared signals, and the like.

[0066] Those skilled in the art can understand that the units and algorithm steps of the examples described in combination with the embodiments can be realized by electronic hardware or a combination of electronic hardware and computer software. Whether the functions are realized in hardware or software manner depends on the specific application and design constraints of the technical solutions. The skilled person can use different methods to realize the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0067] Although the specific embodiments of the present application are described above in combination with the drawings, it is not a limitation on the scope of protection of the present application. Those skilled in the art should understand that various modifications or variations made by those skilled in the art without creative labor on the basis of the technical solutions of the present application are still within the scope of protection of the present application.

Claims

1. A method for detecting moisture in cut tobacco based on thermal analysis and infrared coupling, characterized in that: include: Under the set gradient temperature test conditions, the tobacco samples were tested by thermal analysis and infrared spectroscopy to obtain the test curve; According to the test curve, determine the heat release substances and heat absorption and release conditions in different temperature ranges, and use this to determine the gradient heating plan; Determine the moisture content and microstructure of tobacco samples under different gradient heating schemes, compare the moisture content of tobacco samples with the standard moisture content to determine whether it meets the national standard error, and evaluate the quality of the tobacco after drying based on the microstructure diagram, so as to optimize the gradient heating scheme; Under the optimized gradient heating scheme, the moisture content of the tobacco to be tested is detected.

2. The method for detecting moisture in cut tobacco based on thermal analysis and infrared coupling as claimed in claim 1, characterized in that: The gradient temperature test conditions include: heating from room temperature to the holding temperature at a heating rate of 5°C / min; maintaining the holding temperature at a constant temperature for a set time; and heating from the holding temperature to the maximum temperature at a heating rate of 5°C / min.

3. The method for detecting moisture in cut tobacco based on thermal analysis and infrared coupling as claimed in claim 1, characterized in that: The process of determining the gradient heating scheme includes: Determine the heat release substances and heat absorption and release during the rapid mass loss stage, the residual mass plateau period when kept at a constant temperature, and the high temperature stage; During the rapid mass loss stage, if the organic components released within the designed temperature range exceed the set threshold or a thermal exothermic peak occurs, the endpoint temperature within the range is too high and needs to be readjusted; During the remaining mass plateau period, if the mass loss in the constant temperature interval exceeds the set threshold and thermal exotherm occurs, one or more detection temperature points are selected below the holding temperature. Otherwise, selection is made based on the mass loss change in the heating interval in the third stage. In the high-temperature stage, the release of pyrolysis substances and the absorption and release of heat at the inflection point temperature are observed. If the release of organic components occurs before the inflection point temperature, the selected detection temperature point is lower than the inflection point temperature; otherwise, the detection temperature point is selected after the inflection point temperature, and no pyrolysis substances are released at the selected detection temperature point.

4. The method for detecting moisture in cut tobacco based on thermal analysis and infrared coupling as claimed in claim 1, characterized in that: The moisture content of tobacco samples was detected by the oven method under different gradient heating schemes. The upper limit of the oven method test temperature did not exceed the minimum temperature of thermal degradation of tobacco. The minimum temperature of thermal decomposition of tobacco was obtained from the mass loss, infrared spectrum and endothermic and exothermic curves. There was an obvious endothermic peak in the heating range, and no exothermic peak appeared.

5. The method for detecting moisture in cut tobacco based on thermal analysis and infrared coupling as claimed in claim 1, characterized in that: The process of evaluating the quality of dried tobacco using the microstructure diagram includes observing the changes in the microstructure of the dried tobacco. After drying, the wrinkles of the tobacco are guaranteed to be stretched but without cracks. If the microstructure after drying of a certain gradient heating scheme shows that the number and width of cracks at the folds are greater than the set threshold, the scheme will be abandoned.

6. The method for detecting moisture in cut tobacco based on thermal analysis and infrared coupling as claimed in claim 1, characterized in that: Compare the moisture content of the tobacco sample with the standard moisture content to determine whether the average value and single deviation meet the national standard test error requirements.

7. A tobacco moisture detection system based on thermal analysis and infrared coupling method, characterized in that: include: The testing module is configured to perform a thermal analysis and infrared combined method test on the tobacco sample under set gradient temperature rising test conditions to obtain a test curve; The scheme determination module is configured to determine the heat-releasing substances and heat absorption and release conditions in different temperature ranges according to the test curve, and thereby determine the gradient heating scheme; The optimization module is configured to determine the moisture content and microstructure of tobacco samples under different gradient heating schemes, compare the moisture content of the tobacco samples with the standard moisture content to determine whether the national standard error is met, and evaluate the quality of the tobacco after drying based on the microstructure, thereby optimizing the gradient heating scheme; The detection module is configured to detect the moisture content of the tobacco to be tested under the optimized gradient heating scheme.

8. An electronic device, characterized in that: The method comprises a memory and a processor, and computer instructions stored in the memory and executed on the processor, wherein when the computer instructions are executed by the processor, the method according to any one of claims 1 to 6 is completed.

9. A computer-readable storage medium, characterized in that Used to store computer instructions, which, when executed by a processor, complete the method according to any one of claims 1 to 6.

10. A computer program product, characterized in that The invention comprises a computer program, which is used to implement the method according to any one of claims 1 to 6 when the computer program is executed by a processor.

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