CN116256338A - Gas detection device and multi-component gas filtering inversion method thereof - Google Patents
Gas detection device and multi-component gas filtering inversion method thereof Download PDFInfo
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Abstract
The invention discloses a gas detection device, which comprises a blackbody radiation source, a focusing mirror, an optical fiber, an absorption tank, a mechanical chopper, a photoelectric detector, a detector matching circuit, an FPGA (field programmable gate array) board and an upper computer which are sequentially connected, wherein full-spectrum radiation light emitted by the blackbody radiation source is coupled into the optical fiber through the focusing mirror, the radiation light enters the absorption tank after being transmitted by the optical fiber, the radiation light is emitted from the absorption tank after being reflected and absorbed for many times in the absorption tank, the mechanical chopper is used for carrying out mechanical modulation, the radiation light reaches the photoelectric detector, the detector matching circuit is used for carrying out noise filtering and signal amplification on electric signals on the surface of the photoelectric detector, then the FPGA board is used for collecting and completing signal processing, and the final gas concentration is inverted on the upper computer. The inversion concentration accuracy obtained by the device while distinguishing multiple gas components is higher, the stability is stronger, the efficiency is faster and the like through the multi-component gas filtering inversion method.
Description
Technical Field
The invention belongs to the technical field of gas detection, and particularly relates to a gas detection device and a multi-component gas filtering inversion method.
Background
The theoretical basis of the spectrum absorption method is Lambert-Beer law, when an optical signal passes through the gas to be detected, the optical signal interacts with gas molecules, when the central wavelength of a light source is consistent with the absorption peak of the gas, the gas can strongly absorb incident light to cause the change of light intensity, and the information of the gas concentration can be obtained by detecting the change of the transmitted light intensity or the reflected light intensity. Because of the different covalent bonds formed between different gas molecules, the vibration and rotation energy levels of the molecules are different, and thus, the self-characteristic absorption spectrum is formed in different wavelength ranges. By identifying the characteristic absorption spectrum of the gas molecules, the gas absorption peak wavelength, and detecting the change in luminous flux, the gas species and concentration can be identified. In recent years, the spectrum absorption method has been rapidly developed, and particularly in the field of environmental pollution monitoring, the main technologies include: single-spectrum laser spectrometry, quantum cascade broad-spectrum laser spectrometry, broad-spectrum LED spectrometry, and the like.
The laser spectrometry is the most widely used method at present, and has the characteristics of high precision, high cost and single measurable gas component. In order to realize concentration measurement of multi-component gas, the existing quantum cascade broad spectrum laser method connects a plurality of lasers in narrow spectrum through a wavelength division multiplexing or time division multiplexing method to realize concentration measurement of specific gas. With the increase of the target gas types, the required specific narrow-band lasers are increased, the requirements on the performance of the optical switch are increased, and the complexity and the cost of the system are greatly increased.
The wide-spectrum LED light source is an emerging measuring method with lower cost than laser spectrum, and has more application in measuring scenes with low precision requirements. The radiation emergent power spectrum cannot be adjusted to a large extent, so that the radiation emergent power spectrum cannot be matched with a high-cost filter wheel to realize multi-component gas concentration measurement. Because the energy can only concentrate near a specific wavelength, the energy can not switch different central absorption lines for detection. That is, when the LED light source model is determined, the central wavelength of the energy concentration is a specific value, and when the rest central wavelengths in the spectrum are detected, a signal with a high signal-to-noise ratio cannot be obtained.
In order to reduce the high cost of a laser spectrum system, the range of a detection center spectral line of a radiation source can be switched at will, the power spectrum distribution is changed greatly, the detection of a high signal-to-noise ratio signal is realized, and a detection system based on a blackbody radiation source is generated. The temperature control precision of a small blackbody radiation source (Micro-Hybrid company JSIR 360-4) is 0.1K, the highest temperature is 1000K, and the cost is only one twentieth of that of a same-power gas laser.
According to the Planckian formula and the Wen law that the blackbody radiation emittance meets, the peak emittance corresponding wavelength of the blackbody temperature is changed by changing the temperature, and then the blackbody radiation power spectrum is changed, so that the selection of different central gas absorption spectrum lines is carried out, the selection of different detection upper and lower limits and the detection precision of different gases is carried out, and the detection of the same kind of gases with different precision and the detection of the same concentration range of multi-component gases is realized through a single radiation source. The system solves the technical problems that the current laser system can only detect single-component gas at high cost, the wide-spectrum LED system can only detect single gas at low signal to noise ratio, the high-cost optical filter is matched to detect multi-component gas and the like.
Disclosure of Invention
One of the purposes of the present invention is to provide a gas detection device, so as to realize different precision detection of the same kind of gas and detection of the same concentration range of the multi-component gas by a single radiation source. In order to achieve the above purpose, the specific scheme of the present application is as follows:
a gas detection device, which comprises a blackbody radiation source, a focusing lens, an optical fiber, an absorption tank, a mechanical chopper, a photoelectric detector, a detector matching circuit, an FPGA board and an upper computer which are connected in sequence,
the blackbody radiation source is used for emitting full-spectrum radiation light;
the focusing mirror is used for receiving blackbody radiation light emitted by the converging blackbody radiation source to perform space optical coupling;
the optical fiber is used for transmitting blackbody radiation light of a middle infrared band coupled by the focusing mirror;
the absorption cell is used for enabling the incident blackbody radiation light in the middle infrared band to be transmitted in the absorption cell for multiple times after being accessed by the optical fiber so as to increase the absorption optical path and then exit;
the mechanical chopper is used for mechanically modulating blackbody radiation light passing through the absorption tank;
the photoelectric detector is used for converting a thermal radiation signal reaching the surface of the photoelectric detector into an electric signal and accessing a subsequent circuit for processing;
the detector matching circuit is used for filtering, denoising and amplifying the electric signals on the photoelectric detector;
the FPGA board is used for collecting electric signals and performing data processing;
the upper computer is used for displaying inverted gas concentration data;
the full-spectrum radiation light emitted by the blackbody radiation source is coupled into an optical fiber through a focusing mirror, the radiation light enters an absorption tank after being transmitted by the optical fiber, the radiation light exits from the absorption tank after being reflected and absorbed for many times in the absorption tank, the radiation light reaches a photoelectric detector through mechanical chopper for mechanical modulation, a detector matching circuit carries out noise filtering and signal amplification on an electric signal on the surface of the photoelectric detector, and then an FPGA (field programmable gate array) board (acquiring and finishing signal processing and inverting the final gas concentration on an upper computer) is adopted.
Further, a temperature controller (% for maintaining the stable emission temperature of the radiant light) is arranged on the blackbody radiation source.
Further, the optical fiber comprises an incident coupling head, a mid-infrared band optical fiber and an outgoing connector.
Further, the absorption cell is a Herriott cell.
Further, the absorption cell is a white-type optical absorption cell.
The invention further aims to provide a multi-component gas filtering inversion method based on the blackbody radiation source, which is characterized in that the absorption line intensity is obtained by comprehensively calculating blackbody power spectrum distribution and gas absorption peak intensity at different temperatures, and when the gas concentration minimum detection limit and the gas concentration minimum detection resolution requirement change, different measurement requirements can be met by selecting different temperatures. In order to achieve the above purpose, the specific scheme of the present application is as follows:
the multi-component gas filtering inversion method based on the gas detection device comprises the following steps of:
s1, selecting a single-component gas measurement mode or a multi-component gas measurement mode;
s2, calculating and selecting a corresponding measurement temperature T according to the measurement time requirement 1 、T 2 、……T n ；
S3, calculating the transmittance tau of different gases at different temperatures a1 、τ a2 、……τ an ；τ b1 、τ b2 、……τ bn ；
S4, corresponding gas transmittance is combined according to an absorption law equation, and a weighted least square method is used for solving a coefficient matrix of the multi-transmittance equation set;
s5, solving a transmittance equation through judging the relation between the coefficient matrix rank and the unknown number, and calculating to obtain the gas concentrations of different components.
Further, based on the law of lambertian absorption of the gas of the single-wave number laser system in the step S3, the formula of the transmittance of the gas may be expressed as:
where τ is the light intensity transmission coefficient, I 1 To be absorbed light intensity, I 0 P is the pressure of the gas to be measured, and is the unit atm; s is S T Is of strong spectral line and is in cm -2 atm -1 The method comprises the steps of carrying out a first treatment on the surface of the X is the percent concentration of the gas in ppm (or considered to be dimensionless); l is gasBulk optical path, unit cm; phi is the linear function of the gas absorption spectrum line, and is in cm.
Further, in the step S4, for the law of lambertian absorption of gas based on the broad-band long wave number system, the formula of the transmittance of the gas may be expressed as:
wherein P is i In a broad spectrum light source system, the total gas transmittance is determined by the line intensity and the light source distribution law.
Further, the step S5 includes the following two cases:
when the rank is equal to the number of unknown numbers, directly solving a transmittance equation to obtain the gas concentrations of different components;
when the rank is greater than the number of unknown numbers, calculating the standard deviation sigma of the transmittance of each group, normalizing different standard deviations to obtain weights, and weighting to solve a transmittance equation to obtain the gas concentrations of different components.
Compared with the prior art, the invention has the following advantages:
(1) According to the invention, by combining a wavelength modulation spectrum and a filtering inversion optimization processing algorithm, according to a Planckian formula and a Wen law which are satisfied by the blackbody radiation emittance, the peak emittance corresponding wavelength of the blackbody temperature can be changed by changing the temperature, so that the blackbody radiation power spectrum is changed, the selection of different central gas absorption spectrum lines is carried out, the selection of different detection upper and lower limits and precision of different gases is realized, the detection of the same kind of gases with different precision and the detection of the same concentration range of the multi-component gases are realized by a single radiation source, and the problems that the current laser system can only detect the single component gases with high cost and the wide-spectrum LED system can only detect the single gas with low signal to noise ratio and the multi-component gases are detected by matching with a high-cost filter are solved;
(2) Compared with the traditional laser source, the blackbody is adopted as a radiation source, and has the characteristics of wide spectrum, capability of detecting a plurality of gas types at the same time, low cost and the like;
(3) The Herriott gas absorption cell is adopted, so that the gas absorption optical path and the gas minimum detection limit are greatly improved, and the ppm level is reached;
(4) Through the multi-component gas filtering inversion method, the inversion concentration accuracy obtained by the device while distinguishing the multi-component gas is higher, the stability is stronger, and the efficiency is faster. Therefore, the invention has wide development prospect in the field of gas detection.
Drawings
FIG. 1 is a schematic diagram of a detecting device according to the present invention;
FIG. 2 is a flow chart of the operation of the detection device of the present invention;
FIG. 3 is a flow chart of a multi-component gas filtering inversion method of the present invention.
Detailed Description
In order to better understand the purpose, structure and function of the present invention, a gas detection device and a multi-component gas filtering inversion method thereof according to the present invention are further described below with reference to the accompanying drawings.
As shown in fig. 1-2, the gas detection device of the invention comprises a blackbody radiation source 1, a focusing lens 3, an optical fiber 4, an absorption cell 5, a mechanical chopper 6, a photoelectric detector 7, a detector matching circuit 8, an FPGA board 9 and an upper computer 10 which are connected in sequence. Specifically, the blackbody radiation source 1 is used for emitting full-spectrum radiation light, the blackbody radiation source 1 is provided with a temperature controller 2 used for maintaining stable emission temperature of the radiation light, and the temperature controller 2 is arranged inside a shell of the blackbody radiation source 1; a focusing mirror 3 for receiving and converging the blackbody radiation light emitted from the blackbody radiation source 1 within a numerical aperture range for performing spatial optical coupling; the optical fiber 4 is used for transmitting the blackbody radiation light of the middle infrared band coupled by the focusing mirror 3, and the optical fiber 4 comprises an incident coupling head, a middle infrared band optical fiber and an emergent connector; an absorption cell 5, in which the incident blackbody radiation light of the mid-infrared band is transmitted multiple times in the absorption cell 5 after being accessed by the optical fiber 4, so as to enlarge the absorption optical path and then exit; a mechanical chopper 6 for mechanically modulating the blackbody radiation light passing through the absorption cell 5; the photoelectric detector 7 is used for converting a thermal radiation signal reaching the surface of the photoelectric detector 7 into an electric signal and accessing a subsequent circuit for processing; the detector matching circuit 8 is used for filtering, denoising and amplifying the electric signal on the photoelectric detector 7; the FPGA board 9 is used for collecting electric signals and performing data processing; the upper computer 10 is used for displaying the inverted gas concentration data; the full-spectrum radiation light emitted by the blackbody radiation source 1 is coupled into an optical fiber 4 through a focusing mirror 3, the radiation light enters an absorption tank 5 after being transmitted through the optical fiber 4, the radiation light exits from the absorption tank 5 after being reflected and absorbed for multiple times in the absorption tank 5, the radiation light is mechanically modulated through a mechanical chopper 6, the radiation light reaches a photoelectric detector 7, a detector matching circuit 8 carries out noise filtering and signal amplification on an electric signal on the surface of the photoelectric detector 7, then an FPGA (field programmable gate array) board 9 collects and completes signal processing, and the final gas concentration is inverted on an upper computer 10. When the device is specifically used, an operator only needs to open the blackbody radiation source 1 and the temperature controller 2 each time, and the final gas concentration is read out from the upper computer 10.
The absorption cell can be a Herriott cell, infrared radiation is reflected in the gas absorption cell for multiple times by utilizing the light path of the confocal concave mirror, and the energy absorption capacity of the light path and the corresponding spectrum is increased; the absorption cell 5 can also be a white type optical absorption cell, the incident light beam is transmitted for a plurality of times after being accessed by the optical fiber, and the incident light beam is emitted after the absorption optical path is enlarged.
As shown in fig. 3, the specific algorithm in the upper computer 10 is a multi-component gas filtering inversion method of a gas detection device, which specifically includes the following steps:
s1, selecting a single-component gas measurement mode or a multi-component gas measurement mode;
s2, calculating and selecting a corresponding measurement temperature T according to the measurement time requirement 1 、T 2 、……T n ；
S3, calculating the transmittance tau of different gases at different temperatures a1 、τ a2 、……τ an ；τ b1 、τ b2 、……τ bn ；
S4, corresponding gas transmittance is combined according to an absorption law equation, and a weighted least square method is used for solving a coefficient matrix of the multi-transmittance equation set;
s5, solving a transmittance equation through judging the relation between the coefficient matrix rank and the unknown number, and calculating to obtain the gas concentrations of different components.
Specifically, the multi-component gas filtering inversion method comprises the steps of selecting a variety range of multi-component gas in a gas chamber, selecting a temperature of a corresponding radiation source, and solving a coefficient matrix of a multi-transmittance equation set by using a weighted least square method, so as to invert specific concentration values of different gas components, thereby realizing the solution of the multi-component gas by a single blackbody radiation source at different radiation temperatures. The specific deduction and operation flow are as follows:
for the gas lambert absorption law based on a single-wave number laser system, the gas transmittance formula can be expressed as:
where τ is the light intensity transmission coefficient, I 1 To be absorbed light intensity, I 0 Is the background light intensity before being absorbed. P is the pressure of the gas to be measured, and is the unit atm; s is S T Is of strong spectral line and is in cm -2 atm -1 The method comprises the steps of carrying out a first treatment on the surface of the X is the percent concentration of the gas in ppm (or considered to be dimensionless); l is the optical path of the gas, and the unit is cm; phi is the linear function of the gas absorption spectrum line, and is in cm.
For the gas lambert absorption law based on a wide-spectrum-segment long wave number system, the gas transmittance formula can be expressed as
Wherein P is i Is the energy distribution law of a wide-spectrum light source on a long wave number, lambda is the light source spectrum width, and delta lambda is the absorption line width.
Therefore, in a broad spectrum light source system, the total gas transmittance is determined by both the line intensity and the light source distribution law.
When a single type of gas is present in the gas cell: and the corresponding gas concentration X value can be obtained by combining the equations.
When there is a multicomponent gas in the gas cell and there is no or a small amount of coincident absorption peak between the two gases, it is assumed that there are two gases a and b: then when the blackbody radiation source temperature is selected to be T 1 And T is 2 For mixed gas at T 1 And T is 2 The total transmittance obtained by measurement in the presence of background radiation can be expressed as
And->
Wherein gas a is at T 1 And T is 2 The transmittance under the condition is +.>
And->
Gas b at T 1 And T is 2 The transmittance under the condition is +.>
And->
Because of P (1，i) And P (2，i) Is the known blackbody temperature T 1 And T is 2 Lower energy distributionThe distribution law is a known distribution calculated by the Planck formula, so that the concentration X of the gas a can be obtained by simultaneously solving a coefficient matrix a With the concentration X of gas b b 。
When the required time sensitivity is not high, three to multiple temperatures can be used to solve for the two mixed gases:
standard deviation sigma of gas transmittance data at three temperatures is obtained respectively 1 、σ 2 、σ 3 . Normalizing them to weights, solving two unknowns of three equations, and further obtaining a more accurate gas a concentration X a With the concentration X of gas b b 。
The device comprises a blackbody radiation source 1, a focusing mirror 3, an optical fiber 4, an absorption cell 5, a mechanical chopper 6, a photoelectric detector 7, a detector matching circuit 8, an FPGA board 9 and an upper computer 10.
When the device is particularly used, the blackbody radiation source 1 is placed at the position of the device light source, and the temperature is controlled and stabilized by the matched temperature controller 2; the emergent light of the blackbody radiation source 1 enters an optical fiber 4 for transmission after being spatially optically coupled by a focusing mirror 3; the output end of the optical fiber 4 is an absorption tank 5, after being absorbed by the absorption tank 5, emergent light is output to a photoelectric detector 7 from the optical fiber 4, an optical signal is converted into an electric signal in a detector matching circuit 8, and then the electric signal is acquired by an FPGA board 9 and is sent to an upper computer 10. In the algorithm processing process, the types of the multi-component gas in the gas chamber are respectively selected, the temperature of the corresponding radiation source is selected, the corresponding gas transmittance is combined, the weighting least square method is used for solving the coefficient matrix of the multi-transmittance equation set, and then the specific concentration values of different gas components are inverted, so that the multi-component gas is solved by the single blackbody radiation source at different radiation temperatures. The operator only needs to open the blackbody radiation source after configuration, and the upper computer 10 software is operated after the calibration of the standard air chamber, so that the inverted gas concentration is read. The equipment has the characteristics of small volume, convenient operation, low gas minimum detection limit and good stability, and can be used in the external field and laboratories.
Finally, it should be noted that: the above embodiments are only for illustrating the technical solution of the present invention, and not for limiting the same; although the invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some or all of the technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit of the invention.
Claims (9)
1. A gas detection device, characterized in that: comprises a blackbody radiation source (1), a focusing mirror (3), an optical fiber (4), an absorption tank (5), a mechanical chopper (6), a photoelectric detector (7), a detector matching circuit (8), an FPGA board (9) and an upper computer (10) which are connected in sequence,
the blackbody radiation source (1) is used for emitting full-spectrum radiation light;
the focusing mirror (3) is used for receiving blackbody radiation light emitted by the converging blackbody radiation source (1) to perform space optical coupling and summation;
the optical fiber (4) is used for transmitting blackbody radiation light of a middle infrared band coupled by the focusing mirror (3);
the absorption cell (5) enables the incident blackbody radiation light in the middle infrared band to be transmitted in the absorption cell (5) for a plurality of times after being accessed by the optical fiber (4) so as to increase the absorption optical path and then to be emitted;
the mechanical chopper (6) is used for mechanically modulating the blackbody radiation light passing through the absorption tank (5);
the photoelectric detector (7) is used for converting a thermal radiation signal reaching the surface of the photoelectric detector (7) into an electric signal and accessing a subsequent circuit for processing;
the detector matching circuit (8) is used for filtering, denoising and amplifying the electric signals on the photoelectric detector (7);
the FPGA board (9) is used for collecting electric signals and performing data processing;
the upper computer (10) is used for displaying inverted gas concentration data;
full spectrum radiation light emitted by the blackbody radiation source (1) is coupled into an optical fiber (4) through a focusing mirror (3), the radiation light enters an absorption tank (5) after being transmitted by the optical fiber (4), the radiation light exits from the absorption tank (5) after being reflected and absorbed for many times in the absorption tank (5), the radiation light is mechanically modulated through a mechanical chopper (6), the radiation light reaches a photoelectric detector (7), a detector matching circuit (8) carries out noise filtering and signal amplification on an electric signal on the surface of the photoelectric detector (7), then an FPGA (field programmable gate array) board (9) collects and completes signal processing, and the final gas concentration is inverted on an upper computer (10).
2. A gas detection apparatus according to claim 1, wherein: the blackbody radiation source (1) is provided with a temperature controller (2) for maintaining stable emission temperature of radiation light.
3. A gas detection apparatus according to claim 1, wherein: the optical fiber (4) comprises an incident coupling head, a middle infrared band optical fiber and an emergent connector.
4. A gas detection apparatus according to claim 1, wherein: the absorption tank is a Herriott tank.
5. A gas detection apparatus according to claim 1, wherein: the absorption cell is a white type optical absorption cell.
6. A multi-component gas filtering inversion method of a gas detection apparatus according to any one of claims 1 to 5, wherein: the method comprises the following steps:
s1, selecting a single-component gas measurement mode or a multi-component gas measurement mode;
s2, calculating and selecting a corresponding measurement temperature T according to the measurement time requirement 1 、T 2 、……T n ；
S3, calculating the transmittance tau of different gases at different temperatures a1 、τ a2 、……τ an ；τ b1 、τ b2 、……τ b n ；
S4, corresponding gas transmittance is combined according to an absorption law equation, and a weighted least square method is used for solving a coefficient matrix of the multi-transmittance equation set;
s5, solving a transmittance equation through judging the relation between the coefficient matrix rank and the unknown number, and calculating to obtain the gas concentrations of different components.
7. The multi-component gas filtering inversion method of claim 6 wherein: in the step S3, based on the law of lambert absorption of the gas of the single-wave number laser system, the formula of the transmittance of the gas may be expressed as:
where τ is the light intensity transmission coefficient, I 1 To be absorbed light intensity, I 0 Is the background light intensity before being absorbed. P is the pressure of the gas to be measured, and is the unit atm; s is S T Is of strong spectral line and is in cm -2 atm -1 The method comprises the steps of carrying out a first treatment on the surface of the X is the percent concentration of the gas in ppm (or considered to be dimensionless); l is the optical path of the gas, and the unit is cm; phi is the linear function of the gas absorption spectrum line, and is in cm.
8. The multi-component gas filtering inversion method of claim 7 wherein: in the step S4, for the law of lambert absorption of gas based on the broad-band long wave number system, the formula of the transmittance of gas may be expressed as:
wherein P is i In a broad spectrum light source system, the total gas transmittance is determined by the line intensity and the light source distribution law.
9. The multi-component gas filtering inversion method of claim 8 wherein: the step S5 includes the following two cases:
when the rank is equal to the number of unknown numbers, directly solving a transmittance equation to obtain the gas concentrations of different components;
when the rank is greater than the number of unknown numbers, calculating the standard deviation sigma of the transmittance of each group, normalizing different standard deviations to obtain weights, and weighting to solve a transmittance equation to obtain the gas concentrations of different components.
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| CN (1) | CN116256338A (en) |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116559105A (en) * | 2023-07-06 | 2023-08-08 | 国科大杭州高等研究院 | Linearization readout circuit system based on gas infrared spectrum detection technology |
| CN117091760A (en) * | 2023-10-20 | 2023-11-21 | 国科大杭州高等研究院 | Single photon time-dependent ranging and gas concentration detection method, device and medium |
| CN117871450A (en) * | 2024-03-12 | 2024-04-12 | 国科大杭州高等研究院 | Cross interference processing method in non-dispersive infrared gas detection |
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2023
- 2023-02-03 CN CN202310053504.9A patent/CN116256338A/en active Pending
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116559105A (en) * | 2023-07-06 | 2023-08-08 | 国科大杭州高等研究院 | Linearization readout circuit system based on gas infrared spectrum detection technology |
| CN116559105B (en) * | 2023-07-06 | 2023-11-14 | 国科大杭州高等研究院 | Linearization readout circuit system based on gas infrared spectrum detection technology |
| CN117091760A (en) * | 2023-10-20 | 2023-11-21 | 国科大杭州高等研究院 | Single photon time-dependent ranging and gas concentration detection method, device and medium |
| CN117091760B (en) * | 2023-10-20 | 2024-02-13 | 国科大杭州高等研究院 | Single photon time-dependent ranging and gas concentration detection method, device and medium |
| CN117871450A (en) * | 2024-03-12 | 2024-04-12 | 国科大杭州高等研究院 | Cross interference processing method in non-dispersive infrared gas detection |
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