A sampling measuring device and method for detecting atmosphere by using terahertz spectrum

Abstract

The application provides a sampling and measuring device and method for detecting atmosphere by using terahertz spectrum. The device comprises a sampling and filtering module, which is used for sampling the atmosphere to obtain target atmosphere, and filtering impurities in the target atmosphere to obtain target atmosphere meeting a first state; a monitoring and control module, which is used for monitoring the gas state of the target atmosphere in the sampling and filtering module, and controlling the target atmosphere to meet the first state when the target atmosphere is discharged from the sampling and filtering module, and monitoring the gas state of the target atmosphere meeting the first state in a sample storage and terahertz spectrum test module, and controlling the target atmosphere meeting the first state to meet a second state in the sample storage and terahertz spectrum test module; and a sample storage and terahertz spectrum test module, which is used for storing the target atmosphere meeting the second state, and testing the target atmosphere by using terahertz spectrum to obtain a test result. The application aims to improve the accuracy and sensitivity of detecting atmosphere by using terahertz spectrum.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of spectrum detection, in particular to a sampling and measuring device and method for detecting atmosphere by using terahertz spectrum. BACKGROUND

[0002] At present, the industrial production processes of building, petroleum, chemical industry, coal, and electric power are facing the problems of releasing / leaking of toxic and harmful substances such as VOCs, which brings great hidden dangers to ecological environment, people's life and property safety, and health. Since the terahertz technology has the advantages of fingerprint spectrum, wideband, high signal-to-noise ratio, and the like, some scholars have carried out researches on the application of the technology in the detection of atmospheric substances, but there is still a certain gap from the actual application. On the one hand, in the process of detecting atmosphere by using terahertz spectrum, the detection process will be disturbed by factors such as water vapor absorption, spectral line broadening under high pressure, and impurity gas components, resulting in problems such as overlapping of terahertz spectrum lines, and increasing the difficulty of spectrum feature recognition. On the other hand, the safety threshold concentration of most dangerous gases is usually low, and the terahertz vibration-rotation absorption intensity of some gas substances is also low, so it is difficult to realize the detection of target concentration. SUMMARY

[0003] Therefore, the present application provides a sampling and measuring device and method for detecting atmosphere by using terahertz spectrum. The purpose is to improve the accuracy and sensitivity of detecting atmosphere by using terahertz spectrum.

[0004] In a first aspect, the present application provides a sampling and measuring device for detecting atmosphere by using terahertz spectrum, which comprises a sampling and filtering module, a sample storage and terahertz spectrum testing module, and a monitoring and control module.

[0005] The sampling and filtering module is used for sampling atmosphere to obtain target atmosphere, and filtering impurities in the target atmosphere to obtain target atmosphere meeting a first state.

[0006] The monitoring and control module is connected with the sampling and filtering module, and is used for monitoring the gas state of the target atmosphere in the sampling and filtering module, and controlling the target atmosphere to meet the first state when being discharged from the gas outlet of the sampling and filtering module.

[0007] The monitoring and control module is connected with the sample storage and terahertz spectrum testing module, and is used for monitoring the gas state of the target atmosphere meeting the first state in the sample storage and terahertz spectrum testing module, and controlling the target atmosphere meeting the first state to meet a second state in the sample storage and terahertz spectrum testing module.

[0008] The sample storage and terahertz spectrum testing module is used for storing the target atmosphere meeting the second state, and testing the target atmosphere meeting the second state by using terahertz spectrum to obtain a test result.

[0009] Optionally, the sample injection filtering module comprises a gas pipeline, a flow collector, a physical filter, a gas pump, a flow monitoring controller, a temperature and humidity sensor, and a bellows; the gas pipeline comprises a catalytic filter;

[0010] The gas inlet end of the gas pipeline is connected with the flow collector; the gas outlet end of the gas pipeline is connected with the physical filter; the gas outlet end of the physical filter is connected with the flow monitoring controller; the gas outlet end of the flow monitoring controller is connected with the pipe segment where the temperature and humidity sensor is arranged; the gas outlet end of the pipe segment where the temperature and humidity sensor is arranged is connected with the bellows; the monitoring control module is connected with the flow monitoring controller through a data transmission link; the monitoring control module is connected with the temperature and humidity sensor through a data transmission link;

[0011] The gas pipeline is used to meet the sampling requirements of the target sampling type by replacing and / or increasing or decreasing the number;

[0012] The catalytic filter is used to convert impurities in the target atmosphere that satisfy a first set condition with the absorption frequency of the to-be-detected substance into substances with the target absorption frequency, and is used to filter particulate matters in the target atmosphere that satisfy a second set condition;

[0013] The physical filter is used to filter water vapor in the target atmosphere that has passed through the catalytic filter, and is used to filter particulate matters in the target atmosphere that satisfy the second set condition;

[0014] The gas pump is used to provide negative pressure for sampling of the target atmosphere;

[0015] The bellows is used to adjust the target sampling point of the flow collector according to the sampling requirements;

[0016] The temperature and humidity sensor is used to monitor the temperature and humidity of the target atmosphere and send the monitoring results to the monitoring control module;

[0017] The flow monitoring controller is used to monitor the flow of the target atmosphere and control the flow of the target atmosphere in response to the control command of the monitoring control module.

[0018] Optionally, the catalytic filter comprises a condenser pipe, a filter bed chamber, a catalyst, glass wool, and a heater;

[0019] The condenser pipe is used to cool the target atmosphere after catalytic filtering;

[0020] The filter bed chamber is used to provide a catalytic space of a preset size and reduce the flow rate of the gas;

[0021] The heater comprises a resistance wire and a temperature controller, and the monitoring control module is connected to the temperature controller through a data transmission link.

[0022] The heater is configured to control the catalytic temperature of the catalytic target atmosphere in response to a control command of the monitoring control module.

[0023] Optionally, the sample storage and terahertz spectrum testing module comprises a terahertz multi-pass gas absorption cell, an adjusting base, an electronic manometer, and a nitrogen cylinder.

[0024] The terahertz multi-pass gas absorption cell is configured to store the target atmosphere in the second state and provide a space for terahertz spectrum testing.

[0025] The adjusting base is configured to adjust the exit angle of the terahertz light.

[0026] The manometer is configured to monitor the pressure in the terahertz multi-pass gas absorption cell and send the monitoring result to the monitoring control module.

[0027] The nitrogen cylinder is configured to provide nitrogen to the terahertz multi-pass gas absorption cell to replace impurity gases in the terahertz multi-pass gas absorption cell.

[0028] Optionally, the terahertz multi-pass gas absorption cell comprises a barrel, a shielding barrel, an incident-side terahertz mirror, an exit-side terahertz mirror, an incident-side flange cover assembly, and an exit-side flange cover assembly.

[0029] The incident-side terahertz mirror is configured to provide an entrance for the incident terahertz light.

[0030] The exit-side terahertz mirror is configured to provide an exit for the exit terahertz light.

[0031] The shielding barrel is configured to absorb scattered terahertz light.

[0032] Optionally, the incident-side terahertz mirror and the exit-side terahertz mirror are both spherical mirrors.

[0033] The concave surfaces of the incident-side terahertz mirror and the exit-side terahertz mirror are opposite to each other, and the principal axes coincide and the concave sections are parallel to each other.

[0034] Optionally, the barrel comprises a pressure monitoring hole, a pumping hole, an atmospheric air inlet hole, a nitrogen gas inlet hole, a first stop valve, a second stop valve, and a third stop valve.

[0035] The first stop valve is configured to control the opening and closing of the pumping hole.

[0036] The second stop valve is configured to control the opening and closing of the atmospheric air inlet hole.

[0037] The third stop valve is configured to control the opening and closing of the nitrogen gas inlet hole.

[0038] Optionally, the incident-side flange cover assembly comprises a flange cover, a viewing window tube, a plano-convex lens, and a light hole flange; the flange cover is connected to the viewing window tube; the light hole flange is connected to the viewing window tube through a flange; and the plano-convex lens is sealed between the light hole flange and the viewing window.

[0039] The emission-side flange cover assembly comprises a flange cover, a viewing window tube, a plano-convex lens, and a light hole flange; the flange cover is connected to the viewing window tube; the light hole flange is connected to the viewing window tube through a flange; and the plano-convex lens is sealed between the light hole flange and the viewing window.

[0040] Optionally, the adjusting base comprises a base plate, a telescopic column, a fixed-length column, a slide rail, and a hinge.

[0041] The base plate is connected to the telescopic column and the fixed-length column, respectively; the upper end of the telescopic column is connected to the slide rail; the slide rail is fixed to the lower end of the cylinder; the fixed-length column is connected to the cylinder through the hinge; and the telescopic column adjusts the angle between the cylinder and the horizontal plane by adjusting the length of the telescopic column through a rotating nut.

[0042] The sampling and measuring device for detecting atmosphere by using terahertz spectrum provided by the embodiment of the present application. The sampling and filtering module is used to sample the atmosphere and filter the impurities in the sampled atmosphere to obtain target atmosphere meeting the first state; the monitoring and control module is used to monitor the gas state of the target atmosphere in the sampling and filtering module and control the target atmosphere to meet the first state when being discharged from the gas outlet of the sampling and filtering module; the monitoring and control module is used to monitor the gas state of the target atmosphere meeting the first state in the sampling and storing and terahertz spectrum testing module and control the target atmosphere meeting the first state to meet the second state in the sampling and storing and terahertz spectrum testing module, so that the target atmosphere can be accurately detected by using terahertz spectrum; the sampling and storing and terahertz spectrum testing module is used to store the target atmosphere meeting the second state and test the target atmosphere meeting the second state by using terahertz spectrum to obtain a test result.

[0043] In a second aspect, the present application provides a sampling and measuring method for detecting atmosphere by using terahertz spectrum, which comprises the following steps:

[0044] Close the first stop valve, the second stop valve, the third stop valve, the gas pump and the nitrogen cylinder valve of the sampling and measuring device for detecting atmosphere by terahertz spectrum, which is the sampling and measuring device for detecting atmosphere by terahertz spectrum described in the first aspect of the application; Start the monitoring control module, and preset the heating temperature of the heater and the control flow of the flow monitoring controller;

[0045] By opening the gas pump and the first stop valve, the terahertz multi-pass gas absorption cell is vacuumed;

[0046] After the terahertz multi-pass gas absorption cell is vacuumed, the first stop valve and the gas pump are closed;

[0047] By opening the third stop valve and the nitrogen cylinder valve, nitrogen gas with a set pressure is injected into the terahertz multi-pass gas absorption cell;

[0048] By closing the third stop valve and the nitrogen cylinder valve, and starting the gas pump and the first stop valve, the terahertz multi-pass gas absorption cell is vacuumed;

[0049] By opening the second stop valve, a target atmosphere in a first state with a set volume is extracted into the terahertz multi-pass gas absorption cell;

[0050] By closing the second stop valve, the target atmosphere in the first state is extracted from the terahertz multi-pass gas absorption cell to a target atmosphere in a second state;

[0051] When the target atmosphere in the second state is in the terahertz multi-pass gas absorption cell, the first stop valve is closed;

[0052] By irradiating terahertz light to the terahertz multi-pass gas absorption cell, the target atmosphere in the second state in the terahertz multi-pass gas absorption cell is subjected to terahertz spectrum test, and a test result is obtained. BRIEF DESCRIPTION OF DRAWINGS

[0053] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the description of the embodiments of the present application. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can also be obtained by those skilled in the art without creative labor.

[0054] Figure 1 is a schematic diagram of a sampling and measuring device for detecting atmosphere by terahertz spectrum according to an embodiment of the present application;

[0055] Figure 2 is a schematic diagram of a terahertz multi-pass gas absorption cell in a sampling and measuring device for detecting atmosphere by terahertz spectrum according to an embodiment of the present application;

[0056] Figure 3 is another schematic view of a terahertz multi-pass gas cell in a sampling and measuring device for detecting atmosphere by terahertz spectroscopy according to an embodiment of the present application.

[0057] BRIEF DESCRIPTION OF DRAWINGS

[0058] Gas pipeline 1; pipeline connection flange 2; clamp 3; rubber gasket 4; current collector 5; catalytic filter 6; condenser tube 6-1; filter bed chamber 6-2; catalyst 6-3; filter material glass wool 6-4; heater 7; resistance wire 7-1; temperature controller 7-2; data transmission link 7-3; physical filter 8; filter bed chamber 8-1; condenser tube 8-2; desiccant 8-3; glass wool 8-4; air pump 9; flow monitoring controller 10; flow meter 10-1; flow control valve 10-2; data transmission link 10-3; bellows 11; temperature and humidity sensor 12; terahertz multi-pass gas cell 13; barrel 13-1; shielding cylinder 13-2; incident side terahertz mirror 13-3; exit side terahertz mirror 13-4; incident side flange cover assembly 13-5; exit side flange cover assembly 13-6; adjustment base 14; base plate 14-1; telescopic column 14-2; fixed length column 14-3; slide rail 14-4; hinge 14-5; first stop valve 13-1-3; second stop valve 13-1-5; third stop valve 13-1-7; 13-1-1 pressure monitoring hole; 13-1-2 air extraction hole; 13-1-4 sample inlet hole; 13-1-6 nitrogen gas inlet hole; 13-5-1 flange cover, 13-5-2 observation window tube, 13-5-3 plano-convex lens, 13-5-4 light hole flange; electronic manometer 15; pressure sensor 15-1; pressure display 15-2; data transmission line 15-3; nitrogen cylinder 16; nitrogen cylinder valve 16-1; data receiver 17; computer 18. DETAILED DESCRIPTION

[0059] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are some embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work fall within the scope of protection of the present application.

[0060] Figure 1 is a schematic view of a sampling and measuring device for detecting atmosphere by terahertz spectroscopy according to an embodiment of the present application. Referring to Figure 1 , the present application provides a sampling and measuring device for detecting atmosphere by terahertz spectroscopy, which comprises: a sample inlet filtering module, a sample storage and terahertz spectroscopy testing module, and a monitoring control module.

[0061] The sampling and filtering module is configured to sample the atmosphere to obtain target atmosphere, and filter impurities in the target atmosphere to obtain target atmosphere meeting a first state.

[0062] The monitoring and control module is connected with the sampling and filtering module, and is configured to monitor the gas state of the target atmosphere in the sampling and filtering module, and control the target atmosphere to meet the first state when being discharged from the gas outlet of the sampling and filtering module.

[0063] The monitoring and control module is connected with the sampling and filtering module, and is configured to monitor the gas state of the target atmosphere in the sampling and filtering module, and control the target atmosphere to meet the first state when being discharged from the gas outlet of the sampling and filtering module.

[0064] The monitoring and control module is connected with the sampling and filtering module, and is configured to monitor the gas state of the target atmosphere in the sampling and filtering module, and control the target atmosphere to meet the first state when being discharged from the gas outlet of the sampling and filtering module.

[0065] In the embodiment of the present application, the sampling and filtering module is configured to sample the atmosphere to obtain target atmosphere, and filter impurities in the target atmosphere to obtain target atmosphere meeting a first state. In the sampling and filtering module, the impurities in the target atmosphere obtained by sampling are filtered, and the impurities in the target atmosphere having the same and / or similar absorption frequency as the target substance to be tested by the terahertz spectrum are converted into substances having no absorption or smaller absorption in the terahertz frequency band, so as to obtain target atmosphere meeting a first state. The target atmosphere meeting the first state indicates that the temperature of the target atmosphere reaches the set temperature and the set humidity when the target atmosphere enters the sampling and terahertz spectrum testing module, and the impurities in the target atmosphere having the same and / or similar absorption frequency as the target substance to be tested by the terahertz spectrum have been converted into substances having no absorption or smaller absorption in the terahertz frequency band.

[0066] In the process of obtaining target atmosphere meeting a first state by the sampling and filtering module, the monitoring and control module connected with the sampling and filtering module is configured to monitor the gas state of the target atmosphere in the sampling and filtering module in real time, and control the target atmosphere to meet the first state when being discharged from the gas outlet of the sampling and filtering module.

[0067] After the target atmosphere in the first state enters the sample storage and terahertz spectrum test module from the sample filtering module, the monitoring control module connected with the sample storage and terahertz spectrum test module monitors the gas state of the target atmosphere in the first state in the sample storage and terahertz spectrum test module in real time, and controls the sample storage and terahertz spectrum test module to process the target atmosphere in the first state, so that the target atmosphere in the first state is in the second state in the sample storage and terahertz spectrum test module. The second state represents that the target atmosphere in the first state reaches the pressure required for terahertz spectrum test in the sample storage and terahertz spectrum test module. The sample storage and terahertz spectrum test module is used for storing the target atmosphere in the second state, providing a test space for terahertz spectrum test, and performing terahertz spectrum test on the target atmosphere in the second state to obtain a final test result.

[0068] The sampling and measuring device for detecting atmosphere by terahertz spectrum provided by the embodiments of the present application. The sample filtering module is used for sampling atmosphere and filtering impurities in the sampled atmosphere to obtain target atmosphere in the first state. The monitoring control module is used for monitoring the gas state of the target atmosphere in the sample filtering module and controlling the target atmosphere to be in the first state when being discharged from the outlet of the sample filtering module. The monitoring control module is used for monitoring the gas state of the target atmosphere in the first state in the sample storage and terahertz spectrum test module and controlling the target atmosphere in the first state to be in the second state in the sample storage and terahertz spectrum test module, so that the target atmosphere can be accurately detected by terahertz spectrum. The sample storage and terahertz spectrum test module is used for storing the target atmosphere in the second state and performing terahertz spectrum test on the target atmosphere in the second state to obtain a test result.

[0069] In the application, the sample injection filter module comprises a gas pipeline, a flow collector, a physical filter, a gas pump, a flow monitoring controller, a temperature and humidity sensor and a bellows; the gas pipeline comprises a catalytic filter; the gas inlet end of the gas pipeline is connected with the flow collector; the gas outlet end of the gas pipeline is connected with the physical filter; the gas outlet end of the physical filter is connected with the flow monitoring controller; the gas outlet end of the flow monitoring controller is connected with a pipe section where the temperature and humidity sensor is arranged; the gas outlet end of the pipe section where the temperature and humidity sensor is arranged is connected with the bellows; the monitoring control module is connected with the flow monitoring controller through a data transmission link; the monitoring control module is connected with the temperature and humidity sensor through a data transmission link; the gas pipeline is used to meet the sampling requirements of a target sampling type by replacing and / or increasing or decreasing the number; the catalytic filter is used to convert impurities in the target atmosphere, which satisfy a first set condition with the absorption frequency of the to-be-detected substance, into substances with the target absorption frequency, and is used to filter particulate matters in the target atmosphere, which satisfy a second set condition in particle size; the physical filter is used to filter water vapor in the target atmosphere that has passed through the catalytic filter, and is used to filter particulate matters in the target atmosphere, which satisfy the second set condition in particle size; the gas pump is used to provide negative pressure for sampling of the target atmosphere; the bellows is used to adjust the target sampling point of the flow collector according to sampling requirements; the temperature and humidity sensor is used to monitor the temperature and humidity of the target atmosphere and send the monitoring result to the monitoring control module; and the flow monitoring controller is used to monitor the flow of the target atmosphere and control the flow of the target atmosphere in response to a control command of the monitoring control module.

[0070] In the embodiment of the application, the sample injection filter module comprises a gas pipeline 1, a flow collector 5, a physical filter 8, a gas pump 9, a flow monitoring controller 10, a temperature and humidity sensor 12 and a bellows 11; and the gas pipeline 1 comprises a catalytic filter 6.

[0071] In the embodiment of the present application, the gas pipeline 1 is connected to the flow collector 5 at the inlet end. The gas pipeline 1 is connected to the physical filter 8 at the outlet end. The outlet end of the physical filter 8 is connected to the flow monitor controller 10. The outlet end of the flow monitor controller 10 is connected to the pipe section where the temperature and humidity sensor 12 is arranged. The outlet end of the pipe section where the temperature and humidity sensor 12 is arranged is connected to the corrugated pipe 11. The monitoring control module is connected to the flow monitor controller 10 through a data transmission link. The monitoring control module is connected to the temperature and humidity sensor 12 through a data transmission link. The gas pipeline 1 is used to meet the sampling requirements of the target sampling type by replacing and / or increasing or decreasing the number of the gas pipeline 1. For example, when sampling the atmosphere at different positions, the flow collector 5 in front of the gas pipeline 1 is placed at the corresponding position to sample the atmosphere by increasing or decreasing the number of the gas pipeline 1. When a longer path is needed to cool the sampled atmosphere, a longer gas pipeline 1 can be replaced or the number of the gas pipeline 1 can be increased to make the transmission path longer and better cool the sampled atmosphere. The catalytic filter 6 is used to convert impurities in the target atmosphere whose absorption frequency meets the first set condition with the target substance to be measured into substances with the target absorption frequency, and to filter particulate matter in the target atmosphere whose particle size meets the second set condition. The impurities meeting the first set condition represent that the absorption frequency of the impurities is the same as the absorption frequency of the target substance, or the deviation between the two is within the set range. The particle size meeting the second set condition represents that the diameter of the particulate matter exceeds the set value. The physical filter 8 is used to filter water vapor in the target atmosphere that has passed through the catalytic filter 6, and to further filter particulate matter in the target atmosphere whose particle size meets the second set condition to prevent the problem of insufficient filtration of the catalytic filter 6. The gas pump 9 is used to provide negative pressure for sampling the target atmosphere. The corrugated pipe 11 is used to adjust the target sampling point of the flow collector 5 according to the sampling requirements. Specifically, the corrugated pipe 11 is a flexible pipe that can change direction at will, so that when sampling the atmosphere at different positions is needed, the flow collector 5 can be adjusted to point to the position based on the attribute of the corrugated pipe changing direction at will. The temperature and humidity sensor 12 is used to monitor the temperature and humidity of the target atmosphere and send the monitoring results to the monitoring control module. Specifically, it is used to monitor the temperature and humidity of the target atmosphere flowing into the sample storage and terahertz spectrum test module. If the temperature and humidity sensor 12 is at room temperature ± 5℃ and the relative humidity is greater than 1%, the flow control valve is adjusted to reduce the flow rate of the target atmosphere, or the physical filter 8 is increased to make the temperature and humidity reach the ideal conditions.

[0072] The flow monitoring controller 10 is used for monitoring the flow of the target atmosphere, and controlling the flow of the target atmosphere in response to the control command of the monitoring control module, so as to make the temperature and humidity of the target atmosphere reaching the sample storage and terahertz spectrum test module finally meet the first state by controlling the flow of the target atmosphere.

[0073] In the embodiment of the present application, the gas pipeline 1 is a hollow stainless steel cavity, and the cavity section is a circular ring. Preferably, the inner circle radius of the circular ring of the cavity section of the gas pipeline 1 is preferably 10 mm, and the circular ring width is preferably 2 mm. The gas pipeline 1 is split type, and can be replaced or adjusted in length by increasing or decreasing the number according to the actual sampling requirements such as use time, type of gas to be measured, test distance, etc. The gas pipeline 1 is connected by pipeline connection flange 2 and clamp 3, and rubber gasket is placed between different sections of the gas pipeline to ensure air tightness. The current collector 5 is installed at the gas inlet end of the gas pipeline 1, which is used to reduce the vortex and improve the stability of the atmosphere entering the gas pipeline 1.

[0074] In the embodiment of the present application, the physical filter 8 is a hollow stainless steel cavity, and the cavity section is a circular ring. The middle position of the physical filter 8 is a filter bed chamber 8-1, and the inner diameter of the section circular ring at the position of the filter bed chamber 8-1 is increased by a set size to provide more catalytic space and reduce the gas flow rate, thereby improving the filtering effect. The two sides of the physical filter 8 are condenser pipes 8-2 for cooling the target atmosphere with increased temperature after catalytic filtration. Dry agent 8-3 is placed in the middle of the filter bed chamber 8-1, and glass wool 8-4 is placed on both sides of the dry agent 8-3. The set size of the increased inner diameter of the section circular ring at the position of the filter bed chamber 8-1 can be set according to the actual application scene, which is not specifically limited here. The dry agent 8-3 is made of one of silica gel, activated alumina and calcium chloride, which is used to remove water vapor in the target atmosphere and generated in the catalytic filtration process.

[0075] In the embodiment of the present application, the monitoring control module includes a data receiver 17 and a computer 18. The data receiver 17 is used to receive the temperature, flow, air pressure and other data monitored by the heater 7, the temperature and humidity sensor 12, the flow monitoring controller 10 and the electronic air gauge 15. The computer 18 is used to display the changes of the temperature, flow, air pressure and other signals, and is used to issue instructions to the heater 7, the flow monitoring controller 10 and the air pump 9 to control the temperature, flow and other parameters.

[0076] In the present application, the catalytic filter comprises: a condenser, a filter bed chamber, a catalyst, glass wool and a heater; the condenser is used for cooling the target atmosphere after catalytic filtration; the filter bed chamber is used for providing a preset size of catalytic space and reducing the gas flow rate; the heater comprises a resistance wire and a temperature controller, the monitoring control module is connected with the temperature controller through a data transmission link; and the heater is used for controlling the catalytic temperature of the target atmosphere in response to the control command of the monitoring control module.

[0077] In the embodiment of the present application, the catalytic filter 6 is a hollow stainless steel cavity, and the cross section of the cavity is a circular ring. The catalytic filter 6 has condensers 6-1 on both sides. The condenser 6-1 at the inlet of the gas is used to cool the target atmosphere, and the condenser 6-1 at the outlet of the gas is used to cool the target atmosphere after catalytic filtration. The inner radius and width of the cross section of the condenser 6-1 are the same as those of the cross section of the gas pipeline 1.

[0078] The middle position of the catalytic filter 6 is a filter bed chamber 6-2. The inner radius of the cross section of the filter bed chamber 6-2 at the position is increased by a preset size, which is used to provide a larger catalytic space and reduce the gas flow rate, thereby improving the catalytic conversion efficiency. The preset size of the increased inner radius of the cross section of the filter bed chamber 6-2 at the position can be adjusted according to the actual application scenario, which is not limited here; the inner radius of the circular ring of the filter bed chamber is preferably 20 mm, and the width of the circular ring is preferably 2 mm. The filter bed chamber 6-2 is placed in the middle of the filter bed chamber 6-2, and the catalyst 6-3 is placed on both sides of the filter bed chamber 6-2. The glass wool 6-4 is used to remove large-particle-size particulate matters in the target atmosphere, and the catalyst 6-3 is one of a noble metal catalyst, a metal oxide low-temperature catalyst and a composite oxide low-temperature catalyst, which is used to convert impurities in the target atmosphere, which satisfy the first set condition with the target substance to be measured, into substances with a target absorption frequency under terahertz light.

[0079] In the embodiment of the present application, the catalytic filter 6 is provided with a heater 7, which comprises a resistance wire 7-1 and a temperature controller 7-2. The resistance wire 7-1 and the temperature controller 7-2 are arranged at the outer edge of the catalytic filter bed. The heater 7 is used to control the catalytic temperature of the target atmosphere in response to the control command of the monitoring control module. The temperature controller 7-2 in the heater 7 receives the control command of the monitoring control module, which includes the catalytic temperature. The temperature controller 7-2 controls the resistance wire 7-1 to heat according to the received control command until the resistance wire 7-1 is heated to the required catalytic temperature. Among them, Figure 1 7-3 in the above formula is a data transmission link for connecting the monitoring control module with the temperature controller 7-2. Preferably, the temperature controller 7-2 can adjust the resistance wire to 0-200℃.

[0080] In the embodiment of the present application, the flow monitoring controller 10 comprises a flow meter 10-1, a flow control valve 10-2 for controlling the flow rate of the target atmosphere through the gas pipeline 1; the flow meter 10-1 is connected with the monitoring control module through a data transmission link for transmitting the flow rate and flow of the target atmosphere through the gas pipeline 1 to the monitoring control module. Wherein, Figure 1 The data transmission link 10-3 is the data transmission link connecting the flow meter 10-1 with the monitoring control module.

[0081] In the embodiment of the present application, the bellows 11 connects the sample storage and terahertz spectrum test module with the flow monitoring controller 10, for changing the spatial position of the collector alignment.

[0082] In the present application, the sample storage and terahertz spectrum test module comprises: a terahertz multi-pass gas absorption cell, an adjusting base, an electronic manometer, a nitrogen cylinder; the electronic manometer comprises a pressure sensor and a pressure display, the monitoring control module is connected with the pressure sensor through a data transmission link; the terahertz multi-pass gas absorption cell is used for storing the target atmosphere meeting the second state and providing a space for terahertz spectrum test; the adjusting base is used for adjusting the exit angle of terahertz light; the manometer is used for monitoring the pressure in the terahertz multi-pass gas absorption cell and sending the monitoring result to the monitoring control module; the nitrogen cylinder is used for providing nitrogen to the terahertz multi-pass gas absorption cell to replace impurity gas in the terahertz multi-pass gas absorption cell.

[0083] In the embodiment of the present application, as shown in Figure 2 and Figure 3 The sample storage and terahertz spectrum test module comprises: a terahertz multi-pass gas absorption cell 13, an adjusting base 14, an electronic manometer 15, a nitrogen cylinder 16; the electronic manometer 15 comprises a pressure sensor 15-1 and a pressure display 15-2, and the monitoring control module is connected with the pressure display 15-2 through a data transmission link. Wherein, Figure 1 The data transmission link 15-3 is the data transmission link connecting the monitoring control module with the pressure display 15-2. The gas pump 9 is used for vacuumizing the terahertz multi-pass gas absorption cell 13.

[0084] The terahertz multi-pass gas absorption cell 13 is used for storing the target atmosphere meeting the second state and providing a space for terahertz spectrum test. The adjusting base 14 is used for adjusting the exit angle of terahertz light. The manometer 15 is used for monitoring the pressure in the terahertz multi-pass gas absorption cell 13 and sending the monitoring result to the monitoring control module; the nitrogen cylinder 16 stores high-purity nitrogen with a purity of 99.999%. The nitrogen cylinder 16 is used for providing nitrogen to the terahertz multi-pass gas absorption cell 13 to replace impurity gas in the terahertz multi-pass gas absorption cell 13, so as to provide a pure gas background.

[0085] In the embodiment of the present application, the electronic pressure gauge 15 has a range of 0-1 atm, including a pressure sensor 15-1 and a pressure display 15-2, the pressure sensor 15-1 and the pressure display 15-2 are used to monitor and record the pressure in the terahertz multi-pass gas absorption cell 13, and a data transmission link transmits the pressure data to the monitoring control module.

[0086] In the present application, the terahertz multi-pass gas absorption cell includes: a cylinder, a shielding cylinder, an incident side terahertz mirror, an exit side terahertz mirror, an incident side flange cover assembly, an exit side flange cover assembly, the incident side terahertz mirror is used to provide an entrance for terahertz light incidence, the exit side terahertz mirror is used to provide an exit for terahertz light emission, and the shielding cylinder is used to absorb scattered terahertz light.

[0087] In the embodiment of the present application, the terahertz multi-pass gas absorption cell 13 is a sealed cavity, which can achieve a vacuum degree of absolute pressure <3 Pa, and a mass spectrometry leak <2.0. The terahertz multi-pass gas absorption cell 13 includes a cylinder 13-1, a shielding cylinder 13-2, an incident side terahertz mirror 13-3, an exit side terahertz mirror 13-4, an incident side flange cover assembly 13-5, and an exit side flange cover assembly 13-6. The incident side terahertz mirror 13-3 is used to provide an entrance for terahertz light incidence, the exit side terahertz mirror 13-4 is used to provide an exit for terahertz light emission, and the shielding cylinder 13-2 is used to absorb scattered terahertz light.

[0088] In the present application, the cylinder includes a pressure monitoring hole, a pumping hole, an atmospheric air inlet hole, a nitrogen gas inlet hole, a first stop valve, a second stop valve, and a third stop valve, the first stop valve is used to control the opening and closing of the pumping hole, the second stop valve is used to control the opening and closing of the atmospheric air inlet hole, and the third stop valve is used to control the opening and closing of the nitrogen gas inlet hole.

[0089] In the embodiment of the present application, the cylinder 13-1 is a stainless steel cavity, and the cavity inner diameter is preferably 82 mm. The cylinder 13-1 is provided with a pressure monitoring hole 13-1-1 and a pumping hole 13-1-2, the pumping hole 13-1-2 is switched controlled by a first stop valve 13-1-3, and is provided with an atmospheric air inlet hole 13-1-4, which is switched controlled by a second stop valve 13-1-5, and is provided with a nitrogen gas inlet hole 13-1-6, which is switched controlled by a third stop valve 13-1-7. The shielding cylinder 13-2 is a black aluminum-based cylinder, the shielding cylinder inner diameter is preferably 80 mm, and the thickness is preferably 2 mm, and is lined on the inside of the cylinder 13-1.

[0090] In the application, the incident side terahertz mirror and the exit side terahertz mirror are both spherical mirrors; the concave surfaces of the incident side terahertz mirror and the exit side terahertz mirror are opposite to each other, and the main optical axes are coincident and the concave sections are parallel to each other.

[0091] In the embodiment of the application, the incident side terahertz mirror 13-3 and the exit side terahertz mirror 13-4 are both spherical mirrors, the concave surfaces of the incident side terahertz mirror 13-3 and the exit side terahertz mirror 13-4 are opposite to each other, the main optical axes of the two are coincident, and the concave sections are parallel to each other, the distance between the concave surface and the intersection of the main optical axis is 300 mm, the radius of the concave section is 80 mm, and the curvature radius is 161 mm. The surface is a gold-plated film with a reflectivity of >99%, an incident light hole is formed on the incident side terahertz mirror 13-3, an exit light hole is formed on the exit side terahertz mirror 13-3, the radii of the exit light hole and the incident light hole are both 25 mm, the normal direction of the incident light hole is coincident with the direction of the incident terahertz wave, and the normal direction of the exit light hole is coincident with the direction of the exit terahertz wave. In this way, the optical path is increased by the back and forth reflection between the two spherical mirrors.

[0092] In the application, the incident side flange cover assembly comprises a flange cover, an observation window tube, a plano-convex lens, and a light hole flange; the flange cover is connected with the observation window tube; the light hole flange is connected with the observation window tube through a flange; and the plano-convex lens is sealed between the light hole flange and the observation window. The exit side flange cover assembly comprises a flange cover, an observation window tube, a plano-convex lens, and a light hole flange; the flange cover is connected with the observation window tube; the light hole flange is connected with the observation window tube through a flange; and the plano-convex lens is sealed between the light hole flange and the observation window.

[0093] In the embodiment of the application, as shown in Figure 2 and Figure 3 The incident side flange cover assembly comprises a flange cover 13-5-1, an observation window tube 13-5-2, a plano-convex lens 13-5-3, and a light hole flange 13-5-4. The flange cover 13-5-1 is connected with the observation window tube 13-5-2 through welding, the light hole flange 13-5-4 is connected with the observation window tube 13-5-2 through a flange, and the plano-convex lens 13-5-3 is sealed between the light hole flange 13-5-1 and the observation window tube 13-5-2. The inner diameter of the observation window tube is preferably 26.5 mm. The inner diameter of the observation window tube 13-5-2 is set to be greater than the radius of the light hole of the incident side terahertz mirror 13-3, the central axis of the observation window tube 13-5-2 is coincident with the direction of the incident terahertz wave, the inner diameter of the light hole flange 13-5-4 is slightly greater than the radius of the light hole of the incident side terahertz mirror 13-3, and the material of the plano-convex lens 13-5-3 is TPX (a polymer of 4-methylpentene).

[0094] The composition structure of the exit side flange cover group is same as that of the entrance side flange cover group, comprising a flange cover, an observation window tube, a plano-convex lens, a light hole flange, the flange cover is connected with the observation window tube through welding, the light hole flange is connected with the observation window tube through flange, and the plano-convex lens is sealed between the light hole flange and the observation window tube, wherein the inner diameter of the observation window tube is preferably 26.5mm, the inner diameter of the observation window tube is set to be greater than the radius of the light hole of the exit side terahertz reflector, the central axis of the observation window tube coincides with the exit direction of the terahertz wave, the inner diameter of the light hole flange is slightly larger than the radius of the light hole of the spherical reflector, and the material of the plano-convex lens is TPX.

[0095] In the application, the adjusting base comprises a base plate, a telescopic column, a fixed length column, a slide rail and a hinge; the base plate is connected with the telescopic column and the fixed length column respectively; the upper end of the telescopic column is connected with the slide rail; the slide rail is fixed to the lower end of the cylinder; the fixed length column is connected with the cylinder through the hinge; and the telescopic column adjusts the included angle between the cylinder and the horizontal plane by adjusting the length through a rotating nut.

[0096] In the embodiment of the application, the adjusting base 14 comprises a base plate 14-1, a telescopic column 14-2, a fixed length column 14-3, a slide rail 14-4 and a hinge 14-5. The base plate 14-1 is made of stainless steel and is connected with the telescopic column 14-2 and the fixed length column 14-3. The upper end of the telescopic column 14-2 is connected with the slide rail 14-4, the slide rail 14-4 is fixed to the lower end of the cylinder 13-1, and the fixed length column 14-3 is connected with the cylinder 13-1 through the hinge 14-4. The telescopic column 14-2 adjusts the length through a rotating nut to adjust the pitch angle of the cylinder 13-1 in the vertical direction, thereby adjusting the exit angle of the terahertz light. The range of the included angle between the cylinder and the horizontal plane is preferably -10° to 10°.

[0097] The application provides a sampling and measuring device for detecting atmosphere by using terahertz spectrum, which uses catalytic filtering and physical filtering methods to avoid the influence of external environment on terahertz spectrum testing, and increases the absorption of terahertz wave by the sample to be detected by increasing the absorption path, thereby improving the accuracy and sensitivity of system detection.

[0098] The application also provides a sampling and measuring method for detecting atmosphere by using terahertz spectrum, which comprises the following steps:

[0099] Step S11: close the first stop valve, the second stop valve, the third stop valve, the gas pump and the nitrogen cylinder valve of the sampling and measuring device for detecting atmosphere by terahertz spectrum, start the monitoring control module, and preset the heating temperature of the heater and the control flow of the flow monitoring controller;

[0100] Step S12: vacuumize the terahertz multi-pass gas cell by opening the gas pump and the first stop valve.

[0101] Step S13: close the first stop valve and the gas pump after vacuumizing the terahertz multi-pass gas cell.

[0102] Step S14: inject nitrogen gas with a set pressure into the terahertz multi-pass gas cell by opening the third stop valve and the nitrogen cylinder valve.

[0103] Step S15: vacuumize the terahertz multi-pass gas cell by closing the third stop valve and the nitrogen cylinder valve, and starting the gas pump and the first stop valve.

[0104] Step S16: extract a target atmosphere in a first state with a set volume into the terahertz multi-pass gas cell by opening the second stop valve.

[0105] Step S17: extract the target atmosphere in the first state from the terahertz multi-pass gas cell to a target atmosphere in a second state by closing the second stop valve.

[0106] Step S18: close the first stop valve when the target atmosphere in the second state is in the terahertz multi-pass gas cell.

[0107] Step S19: perform terahertz spectrum test on the target atmosphere in the second state in the terahertz multi-pass gas cell by injecting terahertz light into the terahertz multi-pass gas cell, and obtain a test result.

[0108] In the embodiment of the present application, the first stop valve 13-1-3, the second stop valve 13-1-5, the third stop valve 13-1-7, the gas pump and the nitrogen cylinder valve of the sampling and measuring device for detecting atmosphere by terahertz spectrum are closed in step S11, so that the terahertz multi-pass gas cell 13 is in a closed state. The sampling and measuring device for detecting atmosphere by terahertz spectrum is the sampling and measuring device for detecting atmosphere by terahertz spectrum of the first aspect of the present application. At this time, the monitoring control module is started, and the heating temperature of the heater 7 is preset to the temperature required for catalytic treatment, and the control flow of the flow monitoring controller 10 is preset.

[0109] Step S12, by opening the gas pump 9 and the first stop valve 13-1-3, the terahertz multi-pass gas cell 7 is pumped to vacuum by the gas pump 9. Step S13, after the terahertz multi-pass gas cell 9 is pumped to vacuum, the first stop valve 13-1-3 and the gas pump 9 are closed. Step S14, the third stop valve 13-1-7 and the nitrogen cylinder valve are opened, nitrogen gas with a set pressure, preferably 1 atm, is injected into the terahertz multi-pass gas cell 13 to dilute the impurity gas remaining in the terahertz multi-pass gas cell 13. Step S15, by closing the third stop valve 13-1-7 and the nitrogen cylinder valve, the terahertz multi-pass gas cell 13 is again in a closed state, and then the gas pump 9 and the first stop valve 13-1-3 are started to pump the terahertz multi-pass gas cell 13 to vacuum again. Step S16, the second stop valve 13-1-5 is opened to extract a set volume of target atmosphere in the first state into the terahertz multi-pass gas cell 13 by the gas pump 9, wherein the set volume v of the target atmosphere in the first state is greater than the volume V of the terahertz multi-pass gas cell. Step S17, the second stop valve 13-1-5 is closed, the target atmosphere in the first state is extracted from the terahertz multi-pass gas cell 13 to the target atmosphere in the second state, that is, the target atmosphere in the first state is first extracted into the terahertz multi-pass gas cell 13 in excess, and then a part of the target atmosphere in the first state is discharged until the target atmosphere in the terahertz multi-pass gas cell 13 meets the second state. Wherein, the target atmosphere in the terahertz multi-pass gas cell 13 meeting the second state represents that the pressure of the target atmosphere in the terahertz multi-pass gas cell 13 reaches the pressure for performing the terahertz spectrum test. Step S18, when the target atmosphere in the terahertz multi-pass gas cell 13 meets the second state, the first stop valve 13-1-3 is closed. Step S19, by injecting terahertz waves into the terahertz multi-pass gas cell 13, the target atmosphere in the terahertz multi-pass gas cell 13 in the second state is tested by terahertz spectrum, and a test result is obtained.

[0110] Each of the embodiments in the specification is described in a progressive manner, and each embodiment focuses on the difference from other embodiments. The same or similar parts between the embodiments can be referred to each other.

[0111] Although the preferred embodiments of the embodiments of the present application have been described, those skilled in the art can make further changes and modifications to the embodiments once they know the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the embodiments of the present application.

[0112] Finally, it is to be understood that the phraseology or terminology such as "first" and "second" etc. used herein is merely intended to differentiate one entity or operation from another entity or operation, without necessarily requiring or implying any actual such relationship or order between such entities or operations. Moreover, the terms "comprising", "including", or any other closure, are intended to cover the non-exclusive inclusion such that a process, method, article, or apparatus that comprises a list of elements does not include those elements alone but can include other elements not expressly listed or even include elements inherent in such process, method, article, or apparatus. Without more limitations, the element defined by the statement "comprising a" does not exclude the presence of additional identical elements in the process, method, article, or apparatus that includes the element.

[0113] The above describes in detail the sampling measuring device and method for detecting atmosphere by using terahertz spectrum provided by the present application. The principle and implementation mode of the present application are described by using specific examples. The above description of the examples is only used to help understand the method of the present application and its core idea. Meanwhile, for the general technical personnel in the field, the specific implementation mode and application range will be changed according to the idea of the present application. In summary, the content of the specification should not be understood as the limitation of the present application.

Claims

1. A sampling measuring device for detecting atmosphere using terahertz spectroscopy, characterized by, The device comprises a sample injection filtering module, a sample storage and terahertz spectrum testing module, and a monitoring control module; The sample injection filtering module is configured to sample the atmosphere to obtain target atmosphere, and filter impurities in the target atmosphere to obtain target atmosphere meeting a first state; The monitoring control module is connected with the sample injection filtering module, configured to monitor the gas state of the target atmosphere in the sample injection filtering module, and control the target atmosphere to meet the first state when being discharged from the gas outlet of the sample injection filtering module; The monitoring control module is connected with the sample storage and terahertz spectrum testing module, configured to monitor the gas state of the target atmosphere meeting the first state in the sample storage and terahertz spectrum testing module, and control the target atmosphere meeting the first state to meet a second state in the sample storage and terahertz spectrum testing module; The sample storage and terahertz spectrum testing module is configured to store the target atmosphere meeting the second state, and perform terahertz spectrum testing on the target atmosphere meeting the second state to obtain a testing result; The sample injection filtering module comprises a gas pipeline, a flow collector, a physical filter, a gas pump, a flow monitoring controller, a temperature and humidity sensor, and a bellows; the gas pipeline comprises a catalytic filter; The gas inlet of the gas pipeline is connected with the flow collector; the gas outlet of the gas pipeline is connected with the physical filter; the gas outlet of the physical filter is connected with the flow monitoring controller; the gas outlet of the flow monitoring controller is connected with a pipe segment where the temperature and humidity sensor is arranged; the gas outlet of the pipe segment where the temperature and humidity sensor is arranged is connected with the bellows; the monitoring control module is connected with the flow monitoring controller through a data transmission link; the monitoring control module is connected with the temperature and humidity sensor through a data transmission link; The gas pipeline is configured to meet the sampling demand of target sampling type by replacing and / or increasing / decreasing the number of the gas pipeline; The catalytic filter is configured to convert impurities in the target atmosphere meeting a first set condition with the absorption frequency of the to-be-tested substance into substances with a target absorption frequency, and filter particulate matters in the target atmosphere meeting a second set condition; The physical filter is configured to filter water vapor in the target atmosphere passing through the catalytic filter, and filter particulate matters in the target atmosphere meeting the second set condition; The gas pump is configured to provide negative pressure for sampling the target atmosphere; The bellows is configured to adjust the target sampling point of the flow collector according to the sampling demand; The temperature and humidity sensor is configured to monitor the temperature and humidity of the target atmosphere, and send the monitoring result to the monitoring control module; The flow monitoring controller is configured to monitor the flow of the target atmosphere, and control the flow of the target atmosphere in response to the control command of the monitoring control module.

2. The sampling measurement device for detecting atmosphere using terahertz spectroscopy according to claim 1, wherein The catalytic filter comprises a condenser pipe, a filter bed chamber, a catalyst, glass wool, and a heater; The condenser pipe is configured to cool the target atmosphere after catalytic filtering; The filter bed chamber is configured to provide a catalytic space with a preset size and reduce the gas flow rate; The heater comprises a resistance wire and a temperature controller, and the monitoring control module is connected to the temperature controller through a data transmission link; The heater is used to control the catalytic temperature of the catalytic target atmosphere in response to the control command of the monitoring control module.

3. The sampling measurement device for detecting atmosphere using terahertz spectroscopy according to claim 1, wherein The sample storage and terahertz spectrum testing module comprises a terahertz multi-pass gas absorption cell, an adjusting base, an electronic manometer, and a nitrogen cylinder; the electronic manometer comprises a pressure sensor and a pressure display, and the monitoring control module is connected to the pressure sensor through a data transmission link; The terahertz multi-pass gas absorption cell is used to store the target atmosphere in the second state and provide a space for terahertz spectrum testing; The adjusting base is used to adjust the exit angle of the terahertz light; The manometer is used to monitor the pressure in the terahertz multi-pass gas absorption cell and send the monitoring result to the monitoring control module; The nitrogen cylinder is used to provide nitrogen to the terahertz multi-pass gas absorption cell to replace the impurity gas in the terahertz multi-pass gas absorption cell.

4. The sampling measurement device for detecting atmosphere using terahertz spectroscopy according to claim 3, wherein The terahertz multi-pass gas absorption cell comprises a barrel, a shielding barrel, an incident-side terahertz mirror, an exit-side terahertz mirror, an incident-side flange cover assembly, and an exit-side flange cover assembly. The incident-side terahertz mirror is used to provide an entrance for the terahertz light; The exit-side terahertz mirror is used to provide an exit for the terahertz light; The shielding barrel is used to absorb the scattered terahertz light.

5. The sampling measurement device for detecting atmosphere using terahertz spectroscopy according to claim 4, wherein Both the incident-side terahertz mirror and the exit-side terahertz mirror are spherical mirrors; The concave surfaces of the incident-side terahertz mirror and the exit-side terahertz mirror are opposite to each other, and the principal axes are coincident and the notch sections are parallel to each other.

6. The sampling measurement device for detecting atmosphere using terahertz spectroscopy according to claim 4, wherein The barrel comprises a pressure monitoring hole, a gas extraction hole, an atmospheric air inlet hole, a nitrogen gas inlet hole, a first stop valve, a second stop valve, and a third stop valve; The first stop valve is used to control the opening and closing of the gas extraction hole; The second stop valve is used to control the opening and closing of the atmospheric air inlet hole; The third stop valve is used to control the opening and closing of the nitrogen gas inlet hole.

7. The sampling measurement device for detecting atmosphere using terahertz spectroscopy according to claim 4, wherein The incident-side flange cover assembly comprises a flange cover, a viewing window tube, a plano-convex lens, and a light hole flange; the flange cover is connected to the viewing window tube; the light hole flange is connected to the viewing window tube through a flange; and the plano-convex lens is sealed between the light hole flange and the viewing window. The exit-side flange cover assembly comprises a flange cover, a viewing window tube, a plano-convex lens, and a light hole flange; the flange cover is connected to the viewing window tube; the light hole flange is connected to the viewing window tube through a flange; and the plano-convex lens is sealed between the light hole flange and the viewing window.

8. The sampling measurement device for detecting atmosphere using terahertz spectroscopy according to claim 3, wherein The adjusting base comprises a base substrate, a telescopic column, a fixed-length column, a slide rail, and a hinge; The base substrate is connected to the telescopic column and the fixed-length column respectively; the upper end of the telescopic column is connected to the slide rail; the slide rail is fixed to the lower end of the barrel; the fixed-length column is connected to the barrel through the hinge; and the telescopic column adjusts the included angle between the barrel and the horizontal plane by adjusting the length through a rotating nut.

9. A sampling measurement method for detecting an atmosphere using terahertz spectroscopy, characterized by, The method comprises: Close the first stop valve, the second stop valve, the third stop valve, the gas pump and the nitrogen cylinder valve of the sampling measurement device for detecting atmosphere by terahertz spectrum, which is the sampling measurement device for detecting atmosphere by terahertz spectrum as claimed in any one of claims 1 to 8; start the monitoring control module, and preset the heating temperature of the heater and the control flow of the flow monitoring controller; Vacuumize the terahertz multi-pass gas cell by opening the gas pump and the first stop valve; After vacuumizing the terahertz multi-pass gas cell, close the first stop valve and the gas pump; Inject nitrogen with a set pressure into the terahertz multi-pass gas cell by opening the third stop valve and the nitrogen cylinder valve; Vacuumize the terahertz multi-pass gas cell by closing the third stop valve and the nitrogen cylinder valve, and starting the gas pump and the first stop valve; Extract a target atmosphere in the first state with a set volume from the terahertz multi-pass gas cell by opening the second stop valve; Extract the target atmosphere in the first state from the terahertz multi-pass gas cell to the target atmosphere in the second state by closing the second stop valve; Close the first stop valve when the target atmosphere in the second state is in the terahertz multi-pass gas cell; Perform terahertz spectrum test on the target atmosphere in the second state in the terahertz multi-pass gas cell by injecting terahertz light into the terahertz multi-pass gas cell, and obtain the test result.

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