CN114923972A - Mixed gas component detection device and method - Google Patents
Mixed gas component detection device and method Download PDFInfo
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- 238000001514 detection method Methods 0.000 title claims abstract description 73
- 238000000034 method Methods 0.000 title claims abstract description 22
- 239000000523 sample Substances 0.000 claims abstract description 22
- 239000007789 gas Substances 0.000 claims description 157
- 239000001307 helium Substances 0.000 claims description 28
- 229910052734 helium Inorganic materials 0.000 claims description 28
- SWQJXJOGLNCZEY-UHFFFAOYSA-N helium atom Chemical compound [He] SWQJXJOGLNCZEY-UHFFFAOYSA-N 0.000 claims description 28
- 230000007246 mechanism Effects 0.000 claims description 24
- XUIMIQQOPSSXEZ-UHFFFAOYSA-N Silicon Chemical compound [Si] XUIMIQQOPSSXEZ-UHFFFAOYSA-N 0.000 claims description 15
- 229910052710 silicon Inorganic materials 0.000 claims description 15
- 239000010703 silicon Substances 0.000 claims description 15
- 239000000758 substrate Substances 0.000 claims description 15
- 239000000203 mixture Substances 0.000 claims description 14
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 13
- 239000002041 carbon nanotube Substances 0.000 claims description 13
- 229910021393 carbon nanotube Inorganic materials 0.000 claims description 13
- VYPSYNLAJGMNEJ-UHFFFAOYSA-N Silicium dioxide Chemical compound O=[Si]=O VYPSYNLAJGMNEJ-UHFFFAOYSA-N 0.000 claims description 9
- ZOKXTWBITQBERF-UHFFFAOYSA-N Molybdenum Chemical compound [Mo] ZOKXTWBITQBERF-UHFFFAOYSA-N 0.000 claims description 8
- 238000005315 distribution function Methods 0.000 claims description 7
- 238000005229 chemical vapour deposition Methods 0.000 claims description 4
- 238000009795 derivation Methods 0.000 claims description 4
- 239000000463 material Substances 0.000 claims description 2
- 230000009286 beneficial effect Effects 0.000 abstract 1
- 230000015556 catabolic process Effects 0.000 description 13
- 238000004458 analytical method Methods 0.000 description 8
- 239000003595 mist Substances 0.000 description 8
- 239000012535 impurity Substances 0.000 description 7
- 238000001228 spectrum Methods 0.000 description 7
- XKRFYHLGVUSROY-UHFFFAOYSA-N Argon Chemical compound [Ar] XKRFYHLGVUSROY-UHFFFAOYSA-N 0.000 description 4
- 239000011261 inert gas Substances 0.000 description 4
- WHXSMMKQMYFTQS-UHFFFAOYSA-N Lithium Chemical compound [Li] WHXSMMKQMYFTQS-UHFFFAOYSA-N 0.000 description 3
- 230000007423 decrease Effects 0.000 description 3
- 229910052744 lithium Inorganic materials 0.000 description 3
- 229910052750 molybdenum Inorganic materials 0.000 description 3
- 239000011733 molybdenum Substances 0.000 description 3
- 238000012806 monitoring device Methods 0.000 description 3
- 238000004451 qualitative analysis Methods 0.000 description 3
- 238000004445 quantitative analysis Methods 0.000 description 3
- 229910052786 argon Inorganic materials 0.000 description 2
- 230000008859 change Effects 0.000 description 2
- 150000001875 compounds Chemical class 0.000 description 2
- 238000010292 electrical insulation Methods 0.000 description 2
- 230000005284 excitation Effects 0.000 description 2
- 230000005281 excited state Effects 0.000 description 2
- 238000004519 manufacturing process Methods 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 229910052754 neon Inorganic materials 0.000 description 2
- GKAOGPIIYCISHV-UHFFFAOYSA-N neon atom Chemical compound [Ne] GKAOGPIIYCISHV-UHFFFAOYSA-N 0.000 description 2
- 230000008569 process Effects 0.000 description 2
- 238000013459 approach Methods 0.000 description 1
- 239000008280 blood Substances 0.000 description 1
- 210000004369 blood Anatomy 0.000 description 1
- 238000009534 blood test Methods 0.000 description 1
- 239000010406 cathode material Substances 0.000 description 1
- 238000009535 clinical urine test Methods 0.000 description 1
- 238000010276 construction Methods 0.000 description 1
- 238000007599 discharging Methods 0.000 description 1
- 238000004868 gas analysis Methods 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000002086 nanomaterial Substances 0.000 description 1
- 238000002360 preparation method Methods 0.000 description 1
- 230000009467 reduction Effects 0.000 description 1
- 238000005070 sampling Methods 0.000 description 1
- 230000035945 sensitivity Effects 0.000 description 1
- 210000002700 urine Anatomy 0.000 description 1
- 230000000007 visual effect Effects 0.000 description 1
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- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
- G01N27/403—Cells and electrode assemblies
- G01N27/406—Cells and probes with solid electrolytes
- G01N27/407—Cells and probes with solid electrolytes for investigating or analysing gases
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- G—PHYSICS
- G01—MEASURING; TESTING
- G01N—INVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
- G01N27/00—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means
- G01N27/26—Investigating or analysing materials by the use of electric, electrochemical, or magnetic means by investigating electrochemical variables; by using electrolysis or electrophoresis
- G01N27/416—Systems
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Abstract
The invention provides a mixed gas component detection device and a method, the device comprises a box body, a plasma generation device and a Langmuir probe, wherein the plasma generation device comprises a cathode, an anode and a power supply, the cathode and the anode are arranged at intervals, are respectively positioned on the inner top wall and the inner bottom wall of the box body and are respectively connected with the power supply, the Langmuir probe is inserted into the box body and is positioned between the cathode and the anode, and the two opposite side walls of the box body are respectively provided with an air inlet and an air outlet. The invention has the beneficial effects that: the portability of the mixed gas detection device is realized, the detection cost is reduced, and the detection efficiency is improved.
Description
Technical Field
The invention relates to the technical field of gas analysis, in particular to a mixed gas component detection device and method.
Background
Currently, sampling is often required to detect a part of the human body function, and an invasive method and a non-invasive method are generally included. The invasive method mainly comprises blood test and urine test, needs to collect human blood and urine samples, and is complex to operate, while the non-invasive method mainly comprises an exhaled gas detection method.
At present, an electronic nose or a gas chromatography-mass spectrometer is mainly adopted to detect mixed gas exhaled by a human body. Where the electronic nose comprises an array of different compounds and different detectors that react with a given compound, the sensitivity and selectivity of the detectors is not suitable for analytically detecting exhaled gas mixtures. The experimental equipment used by the gas chromatography-mass spectrometer needs higher vacuum requirements, different detectors are needed for different types of detected gas, the detection equipment is expensive, large in size and low in detection efficiency, and meanwhile, the equipment needs to be operated by related professional technicians and needs to be maintained regularly, so that the detection cost is greatly increased.
Disclosure of Invention
The invention solves the problems of reducing the detection cost of the exhaled mixed gas and improving the detection efficiency.
In order to solve the above problems, the present invention provides a mixed gas component detection apparatus and method.
In a first aspect, the present invention provides a mixed gas component detecting device, including a box, a plasma generating device and a langmuir probe, wherein the plasma generating device includes a cathode, an anode and a power supply, the cathode and the anode are disposed at an interval, are respectively located on an inner top wall and an inner bottom wall of the box, and are respectively connected to the power supply, the langmuir probe is inserted into the box and is located between the cathode and the anode, and two opposite side walls of the box are respectively provided with an air inlet and an air outlet.
According to the mixed gas component detection device, a user can exhale from the gas inlet, gas can flow out of the gas outlet, in the process, power is supplied by the power supply, the cathode and the anode in the box body carry out discharge breakdown on the mixed gas exhaled by the user, plasma parameters generated by ionization can be obtained by using the Langmuir probe, and gas component analysis can be further carried out through a current-voltage relation, for example. The device simple structure conveniently carries, can effectively improve mist's detection efficiency, can correspondingly reduce simultaneously and detect the cost.
Further, the cathode includes a molybdenum sheet.
Further, the anode comprises a silicon substrate and carbon nanotubes, the silicon substrate is attached to the inner bottom wall of the box body, and the carbon nanotubes are grown on the top surface of the silicon substrate by a chemical vapor deposition method.
Furthermore, the box body is made of quartz glass.
Further, the power supply includes a battery and a voltage adjustment mechanism connected to the battery for adjusting the voltage applied to the cathode and the anode.
Further, the mixed gas component detection device further comprises a distance adjusting mechanism for adjusting the distance between the cathode and the anode.
Further, the mixed gas component detection device further comprises a helium supply mechanism, and the helium supply mechanism is used for being communicated with the box body.
In a second aspect, the present invention provides a mixed gas component detection method based on the mixed gas component detection apparatus described above, including:
introducing a gas to be detected mixed with a calibration gas into a box body, wherein the distance between a cathode and an anode and the applied voltage are determined based on the Paschen law and the calibration gas;
when the gas is ionized, obtaining plasma parameters through a Langmuir probe;
and determining the composition of the gas to be detected through the plasma parameters.
According to the mixed gas detection method, calibration gas can be determined in advance, usually inert gas such as helium is selected, based on relevant characteristics of the calibration gas, the optimal applied voltage and the optimal distance between a cathode and an anode of a mixture detection device can be determined according to the Paschen law, the product of the distance and the atmospheric pressure is located on the right of the lowest point of a U-shaped Paschen curve, therefore, when the mixed gas and the calibration gas exhaled by a user pass through a box body, due to the fact that the pressure in the box body is reduced, the product of the distance and the current pressure is reduced to the lowest point of the U-shaped Paschen curve, the mixed gas is further ionized to generate plasma, plasma parameters can be obtained by using a Langmuir probe, and gas composition analysis can be further carried out through the current-voltage relation. The method can ensure the detection precision of the mixed gas, effectively improve the detection efficiency and correspondingly reduce the detection cost.
Further, the determining the composition of the gas to be detected through the plasma parameters comprises:
acquiring a current/voltage curve of the plasma;
performing second-order derivation on the current/voltage curve to obtain an electron energy distribution function with a characteristic electron peak;
and determining the components of the gas to be detected according to the characteristic electron peak on the electron energy distribution function.
Further, the calibration gas is helium, the distance ranges from 40 to 50mm, and the applied voltage is 400V.
Drawings
FIG. 1 is a schematic structural view of a mixed gas component detection apparatus according to an embodiment of the present invention;
FIG. 2 is a Paschen curve for helium gas according to an embodiment of the invention;
FIG. 3 is a schematic flow chart of a mixed gas component detection method according to an embodiment of the present invention;
FIG. 4 shows an example of the present invention containing N 2 And CO.
Description of reference numerals:
1-a cathode; 2-an anode; 21-a silicon substrate; 22-carbon nanotubes; 3-a power supply; 4-a box body; 5-langmuir probe; 6-air inlet; and 7, air outlet holes.
Detailed Description
In order to make the aforementioned objects, features and advantages of the present invention comprehensible, embodiments accompanied with figures are described in detail below.
Referring to fig. 1, a mixed gas component detecting apparatus according to an embodiment of the present invention includes a case 4, a plasma generating device and a langmuir probe 5, wherein the plasma generating device includes a cathode 1, an anode 2 and a power supply 3, the cathode 1 and the anode 2 are disposed at an interval and are respectively located on an inner top wall and an inner bottom wall of the case 4, and are respectively connected to the power supply 3, the langmuir probe 5 is inserted into the case 4 and is located between the cathode 1 and the anode 2, and two opposite side walls of the case 4 are respectively provided with a gas inlet 6 and a gas outlet 7.
Specifically, the box body 4 is a cavity structure, and the interior thereof can be in a hollow cuboid shape, and correspondingly, the exterior thereof can also be in a cuboid shape, so that the carrying and the use are convenient. The plasma generating device comprises a cathode 1, an anode 2 and a power supply 3, wherein the anode 2 can be arranged on the inner bottom wall of the box body 4 and can be connected with the negative electrode of the power supply 3 through a lead, and the cathode 1 can be arranged on the inner top wall of the box body 4 and can be connected with the positive electrode of the power supply 3 through a lead so as to discharge and breakdown mixed gas in the box body 4 to generate plasma. A through hole may be opened in the sidewall of the box 4 so that a Langmuir (Langmuir) probe 5 is inserted into the box 4 from the through hole and its tip is positioned between the cathode 1 and the anode 2 for obtaining plasma parameters and further performing gas impurity analysis. An air inlet 6 can be arranged on the left side wall of the box body 4 for introducing the mixed gas to be detected, for example, the mixed gas is directly exhaled by a user, and an air outlet is arranged on the right side wall of the box body 4 for discharging the detected mixed gas.
In the case of detection, a calibration gas, which can be determined in advance and is usually an inert gas such as helium (He), is also introduced into the cartridge 4 together with the mixed gas. Based on the relevant characteristics of the calibration gas, the optimum applied voltage and spacing of the cathode 1 and anode 2 may be determined according to paschen's law.
Paschen's law includes:
wherein constants a and B represent gas related parameters, for example, if the calibration gas is helium, it is the related parameter of helium, p represents the pressure of the ionization chamber, i.e., the gas pressure inside the box 4, V represents the breakdown voltage, γ represents the cathode secondary electron emission coefficient, which depends on the cathode material, L represents the distance between the cathode 1 and the anode 2, and pL represents the product of the pressure of the ionization chamber and the cathode anode-anode distance.
It can be seen that either pL or V has a minimum value, i.e., (pL) min And (V) min . As shown in fig. 2, the paschen curve of helium as the calibration gas is shown as a U-shaped curve, the breakdown voltage decreases as the product of the gas pressure and the distance between the anode 2 and the cathode 1 increases, the breakdown voltage has a minimum value, and the breakdown voltage increases as the product of the gas pressure and the distance between the anode 2 and the cathode 1 increases. The minimum value of the breakdown voltage is taken as the applied voltage of the mixed gas detection device of the embodiment, and the right side value of the minimum value of the breakdown voltage is taken to obtain the corresponding distance value between the cathode 1 and the anode 2, which is taken as the distance between the cathode 1 and the anode 2 of the mixed gas detection device of the embodiment. It can be understood that, at this time, the detecting device is in a stable state, when the user blows in gas from the gas inlet 6, the gas pressure in the box body 4 is reduced due to the increase of the gas flow, the product of the gas pressure and the distance between the cathode 1 and the anode 3 is reduced, the breakdown voltage is reduced accordingly, the breakdown voltage reaches the minimum value, and the discharge between the cathode 1 and the anode 2 of the detecting device breaks down to generate plasma.
In the embodiment, a user can exhale from the air inlet, the air flows out from the air outlet, in the process, the power supply supplies power, the cathode and the anode in the box body carry out discharge breakdown on the mixed air exhaled by the user, plasma parameters generated by ionization can be obtained by using the Langmuir probe, and further gas component analysis can be carried out through a current-voltage relation, for example. The device simple structure conveniently carries, can effectively improve mist's detection efficiency, simultaneously can corresponding reduction detection cost.
Optionally, the cathode 1 comprises a molybdenum sheet.
Specifically, the cathode 1 is made of metal molybdenum sheets, the conductivity is good, the size is small, the use requirement for space is low, the molybdenum sheets are used as the cathode 1, the portability of the mixed gas detection device can be improved, the price of the molybdenum sheets is reasonable, the production cost of the mixed gas detection device can be effectively reduced, and the practicability of the mixed gas detection device is improved. For example, a molybdenum sheet with a thickness of 0.15mm is selected as the cathode 1 of the mixed gas detecting device of the present embodiment.
Optionally, the anode 2 includes a silicon substrate 21 and carbon nanotubes 22, the silicon substrate 21 is attached to the inner bottom wall of the box body 4, and the carbon nanotubes 22 are grown on the top surface of the silicon substrate 21 by a chemical vapor deposition method.
Specifically, as shown in fig. 1, the anode 2 includes a silicon substrate 21 and a carbon nanotube 22, one end of the silicon substrate 21 is attached to the inner bottom wall of the box 4, and the other end of the silicon substrate is used for growing a layer of carbon nanotube 22 by chemical vapor deposition, and the carbon nanotube 22 is disposed opposite to the cathode 1. The silicon substrate is wide in application and low in price, the feasibility of the mixed gas detection device is effectively improved, and the production cost is reduced; the carbon nano tube has higher conductivity and heat resistance, and is light as a one-dimensional nano material, stable in structure and high in hardness. The silicon substrate 21 and the carbon nanotube 22 are used as the anode 2, so that the portability of the mixed gas detection device can be effectively improved, the stability is high, the price is low, the maintenance, the replacement and the like of equipment are reduced, the service life of the mixed gas detection device is longer, and the detection cost is effectively reduced.
Optionally, the material of the box body 4 is quartz glass.
Specifically, box body 4 adopts quartz glass to make inside hollow cuboid shape, because quartz glass has advantages such as hardness is big, high temperature resistant to quartz glass preparation box body 4 for the mist detection device sound construction increases life, and simultaneously, quartz glass still has higher electrical insulation, produces electric leakage phenomenon when avoiding monitoring devices to carry out the mist ionization, increases the mist and detects the security. In addition, the size of the box body 4 can be set to be convenient for hand holding, thereby being convenient for carrying and using.
In this embodiment, as shown in fig. 1, the molybdenum sheet and the carbon nanotube with good electrical conductivity are respectively used as the cathode 1 and the anode 2, so as to ionize the mixed gas to generate plasma, thereby effectively increasing the detection efficiency, and meanwhile, the quartz glass is used as the box body 4 to protect the internal structure, thereby increasing the portability and the service life of the monitoring device, and the quartz glass has high electrical insulation property, so as to greatly improve the safety of the monitoring device.
Alternatively, the power supply 3 includes a battery and a voltage adjusting mechanism connected to the battery for adjusting the voltage applied to the cathode 1 and the anode 2.
Specifically, the power supply 3 includes a battery connected to the voltage adjustment mechanism for supplying the applied voltage to the cathode 1 and the anode 2, and a voltage adjustment mechanism for adjusting the applied voltage supplied from the battery so that the applied voltage satisfies a breakdown voltage required for the detection device. For example, a lithium battery is selected as the battery of the mixed gas detection device, as can be seen from fig. 2, when helium is selected as the calibration gas to perform component detection on the mixed gas, the required applied voltage is 400V, and the maximum safe voltage of the battery is 36V, at this time, the applied voltage is amplified to 400V by using the voltage adjustment mechanism, so as to meet the voltage required for detection, and the voltage adjustment mechanism may be a micro voltage power amplifier. In addition, if the required applied voltage is less than the maximum safe voltage 36V of the lithium battery, the lithium battery with proper voltage can be selected to meet the detection requirement.
In this embodiment, voltage adjustment mechanism is set up and voltage that the battery provided is adjusted for the applied voltage satisfies the required voltage of mist detection device, avoids leading to negative pole 1 and positive pole 2 can not normally discharge and puncture and produce plasma because of applying voltage not enough, guarantees detection device's normal operating.
Optionally, the mixed gas component detecting device further includes a distance adjusting mechanism for adjusting a distance between the cathode 1 and the anode 2.
Specifically, the mixed gas detection device further includes a spacing adjustment mechanism for adjusting the spacing between the cathode 1 and the anode 2. Illustratively, the distance adjusting structure can be a rack-and-pinion mechanism, and the rack is linearly moved by rotating the pinion to drive the cathode 1 and the anode 2 connected thereto to approach or move away from each other, thereby adjusting the distance between the two.
In this embodiment, owing to can choose for use the demarcation gas of different grade type according to actual conditions, required electrode spacing is also different with the applied voltage among the mixed gas detection device, confirm the required applied voltage of gas ionization of demarcation and the electrode spacing that corresponds through paschen law, then utilize interval guiding mechanism to adjust electrode spacing, make detection device change after the gas of demarcation, can normal operating under the condition that keeps detecting the precision, realize a tractor serves several purposes, effectively increased mixed gas detection device practicality, reduce the detection cost.
Optionally, the mixed gas component detecting device further comprises a helium gas supply mechanism, and the helium gas supply mechanism is used for communicating with the box body 4.
The mixed gas detection device also comprises a helium supply mechanism, wherein the helium supply mechanism is communicated with the box body 4 and is used for introducing helium as calibration gas to detect the components of the mixed gas during the detection of the mixed gas. In addition, because the inert gas properties are similar, other inert gases such as neon, argon and the like can be selected as the calibration gas, and a neon supply mechanism or an argon supply mechanism and the like are correspondingly arranged.
In this embodiment, set up helium feed mechanism, let in the helium and carry out the component of mist and detect as calibration gas, can accomplish the component analysis of mist fast, reduce the time cost that detects, promote detection efficiency.
Referring to fig. 3, a mixed gas component detecting method according to another embodiment of the present invention is based on the above mixed gas component detecting device; the method comprises the following steps:
step S1, introducing the gas to be detected mixed with calibration gas into the box body 4, wherein the distance between the cathode 1 and the anode 2 and the applied voltage are determined based on Paschen law and the calibration gas;
step S2, when the gas is ionized, obtaining plasma parameters through the langmuir probe 5;
and step S3, determining the composition of the gas to be detected through the plasma parameters.
Specifically, when the gas composition is analyzed by using the mixed gas composition detection device, the calibration gas is determined first, and then the applied voltage required for the calibration gas and the distance between the cathode 1 and the anode 2 are determined according to paschen's law. In the present embodiment, helium is used as the calibration gas, and as can be seen from fig. 2, the voltage required to be applied by helium is 400V. During detection, a user blows air into the air inlet 6 and simultaneously introduces helium gas by using a helium gas supply device, 400V voltage is applied to the cathode 1 and the anode 2 through the power supply 3, and the mixed gas is discharged and broken down to generate plasma. Where it is sufficient to ionize almost all gases exhaled by the human body based on the metastable atomic energy of helium. Further, different voltages can be applied to the langmuir probe 5 and the plasma, so that the currents generated by the plasma at the different voltages can be obtained, and the composition analysis of the mixed gas can be realized according to the obtained current voltage data.
In this embodiment, the calibration gas may be determined in advance, and based on the relevant characteristics of the calibration gas, the optimum applied voltage and the optimum distance between the cathode and the anode of the mixture detecting apparatus may be determined according to paschen's law, such that the product of the distance and the atmospheric pressure is located on the right of the lowest point of the U-shaped paschen curve, so that when the mixed gas and the calibration gas exhaled by the user pass through the cartridge, the pressure in the cartridge decreases, and the product of the distance and the current pressure decreases to the lowest point of the U-shaped paschen curve, so as to ionize the mixed gas and generate plasma, and the plasma parameters may be obtained by using the mueller probe, and the gas composition may be further analyzed through, for example, the current-voltage relationship. The method can not only ensure the detection precision of the mixed gas, but also effectively improve the detection efficiency and correspondingly reduce the detection cost.
Optionally, the determining the composition of the gas to be detected by the plasma parameter comprises:
acquiring a current/voltage curve of the plasma;
performing second-order derivation on the current/voltage curve to obtain an electron energy distribution function with a characteristic electron peak;
and determining the components of the gas to be detected according to the characteristic electron peak on the electron energy distribution function.
Specifically, the cathode 1 and the anode 2 are supplied with power by the power supply 3 to generate plasma through discharge breakdown, a certain voltage is applied to the plasma by using the langmuir probe 5 to obtain the current change of the plasma under the certain voltage to generate the current/voltage curve of the plasma, the probe current of the current/voltage curve is subjected to second-order derivation relative to the probe voltage to obtain an electron energy distribution function with characteristic electron peaks to generate a plasma electron energy spectrum, and as shown in fig. 4, by fitting the area ratio (the area corresponding to the dotted line part) of each characteristic electron peak, for example, N in the mixed gas can be obtained 2 And the ratio of the CO component, and realizes the analysis of the components of the mixed gas.
In the embodiment, the Langmuir probe is used for collecting a current/voltage curve, then a plasma electron energy spectrum is generated, the quantitative analysis of the mixed gas is carried out according to the area ratio in the plasma electron energy spectrum, the component detection of the mixed gas is completed, the quantitative analysis of the detected gas is carried out by calculating the plasma electron energy spectrum, the detection result is more visual, meanwhile, the method is simple to operate, and the component detection efficiency of the mixed gas is improved.
It can be understood that the plasma electron energy spectrum contains the energy of atoms and molecules of the components in the detected gas, and the ionization energy of each component is obtained according to the initial kinetic energy of different characteristic electron peaks on the plasma electron energy spectrum and the excitation energy of excited state atoms, so that the components of the impurity (i.e. the mixed gas to be detected) can be determined, and the qualitative analysis of the impurity is realized. For example, according to Penning (Penning) ionization reaction: a. the * +M→A+M + +e{E f Due to impurity atoms (molecules) having different ionization potentials E i Thus Penning (Penning) electrons have different initial kinetic energies E f . Determination of the ionization potential (E) of gas atoms (molecules) by analysis of the energies of these different electrons i ＝E m -E f ) Thereby achieving the purpose of identifying the gas components. In general, the transport gas (i.e., the calibration gas) may be helium, and the ionization energy of the impurity is obtained by knowing the initial kinetic energies of different characteristic electron peaks on the electron energy spectrum of the plasma and the excitation energy of excited state atoms (He), thereby obtaining the ionization energy of the impurityAnd determining the components of the impurities in one step to realize qualitative analysis of the impurities. Due to energy E of metastable He atoms m 19.8eV, is sufficient to ionize any (other than Ne) gas atom (molecule), and therefore helium is often used as the transport gas for qualitative analysis and detection of gas atoms (molecules). Therefore, the quantitative analysis of the detection gas can be completed quickly, the time cost of detection is reduced, and the detection efficiency is improved.
Alternatively, the calibration gas is helium, and the distance between the cathode 1 and the anode 2 is in the range of 40 to 50mm as calculated by paschen's law, and the minimum applied voltage is 400V. Helium is used as calibration gas, and a detection device is arranged according to obtained data to detect the components of the mixed gas, so that the detection efficiency can be improved while the accuracy of a detection result is ensured, and the detection cost is correspondingly reduced.
Although the present invention has been disclosed above, the scope of the present invention is not limited thereto. Various changes and modifications may be made by those skilled in the art without departing from the spirit and scope of the invention, and these changes and modifications are intended to be within the scope of the invention.
Claims (10)
1. The utility model provides a mixed gas composition detection device, its characterized in that includes box body (4), plasma generating device and Langmuir probe (5), plasma generating device includes negative pole (1), positive pole (2) and power (3), negative pole (1) with positive pole (2) interval sets up and is located respectively the interior roof and the interior bottom wall of box body (4), and respectively with power (3) are connected, Langmuir probe (5) insert in box body (4) and be located negative pole (1) with between the positive pole (2), the relative both sides wall of box body (4) is provided with air inlet (6) and gas outlet (7) respectively.
2. The mixed gas component detecting device according to claim 1, wherein the cathode (1) includes a molybdenum sheet.
3. The mixed gas component detecting device according to claim 1, wherein the anode (2) includes a silicon substrate (21) and carbon nanotubes (22), the silicon substrate (21) is attached to an inner bottom wall of the box body (4), and the carbon nanotubes (22) are grown on a top surface of the silicon substrate (21) by a chemical vapor deposition method.
4. The mixed gas component detecting device according to claim 1, wherein the material of the cartridge body (4) is quartz glass.
5. The mixed gas component detecting apparatus according to claim 1, wherein the power source (3) includes a battery and a voltage adjusting mechanism connected to the battery and adapted to adjust the voltage applied to the cathode (1) and the anode (2).
6. The mixed gas component detecting apparatus according to claim 1, further comprising a spacing adjustment mechanism for adjusting a spacing between the cathode (1) and the anode (2).
7. The mixed gas component detecting device according to claim 1, further comprising a helium gas supply mechanism for communicating with the cartridge body (4).
8. A mixed gas component detecting method according to any one of claims 1 to 7, characterized by comprising:
introducing a gas to be detected mixed with a calibration gas into a box body (4), wherein the spacing between the cathode (1) and the anode (2) and the applied voltage are determined based on Paschen's law and the calibration gas;
obtaining plasma parameters through a Langmuir probe (5) when the gas is ionized;
and determining the composition of the gas to be detected through the plasma parameters.
9. The mixed gas component detecting method according to claim 8, wherein the determining the component of the gas to be detected by the plasma parameter includes:
acquiring a current/voltage curve of the plasma;
performing second-order derivation on the current/voltage curve to obtain an electron energy distribution function with a characteristic electron peak;
and determining the components of the gas to be detected according to the characteristic electron peak on the electron energy distribution function.
10. The mixed gas component detecting method according to claim 8, wherein the calibration gas is helium, the interval is in a range of 40 to 50mm, and the applied voltage is 400V.
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20060251543A1 (en) * | 2002-12-20 | 2006-11-09 | Rensselaer Polytechnic Institute | Miniaturized gas sensors featuring electrical breakdown in the vicinity of carbon nanotube tips |
| US20070172959A1 (en) * | 2003-12-15 | 2007-07-26 | Fuellemann Joerg | Method and device for electrically testing fuels and combustibles by generating a plasma |
| US20120084026A1 (en) * | 2010-10-04 | 2012-04-05 | Tokyo Electron Limited | Method and system for characterizing a plasma |
| KR20120074046A (en) * | 2010-12-27 | 2012-07-05 | 재단법인 포항산업과학연구원 | Plasma generating device and plasma controlling method using the same |
| CN106568805A (en) * | 2016-11-08 | 2017-04-19 | 华中科技大学 | Highly-integrated Langmuir probe diagnosis system and method |
| CN114088690A (en) * | 2021-11-09 | 2022-02-25 | 哈尔滨工业大学 | Device and method for analyzing and detecting gas impurities in open environment |
| CN114216808A (en) * | 2021-11-18 | 2022-03-22 | 中国人民解放军军事科学院国防工程研究院工程防护研究所 | Gas impurity detection device and detection method |
-
2022
- 2022-04-21 CN CN202210421312.4A patent/CN114923972A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20060251543A1 (en) * | 2002-12-20 | 2006-11-09 | Rensselaer Polytechnic Institute | Miniaturized gas sensors featuring electrical breakdown in the vicinity of carbon nanotube tips |
| US20070172959A1 (en) * | 2003-12-15 | 2007-07-26 | Fuellemann Joerg | Method and device for electrically testing fuels and combustibles by generating a plasma |
| US20120084026A1 (en) * | 2010-10-04 | 2012-04-05 | Tokyo Electron Limited | Method and system for characterizing a plasma |
| KR20120074046A (en) * | 2010-12-27 | 2012-07-05 | 재단법인 포항산업과학연구원 | Plasma generating device and plasma controlling method using the same |
| CN106568805A (en) * | 2016-11-08 | 2017-04-19 | 华中科技大学 | Highly-integrated Langmuir probe diagnosis system and method |
| CN114088690A (en) * | 2021-11-09 | 2022-02-25 | 哈尔滨工业大学 | Device and method for analyzing and detecting gas impurities in open environment |
| CN114216808A (en) * | 2021-11-18 | 2022-03-22 | 中国人民解放军军事科学院国防工程研究院工程防护研究所 | Gas impurity detection device and detection method |
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