Electron impact ionization detector for chromatography

Abstract

The invention discloses an electron impact ionization detector for chromatography, and relates to the field of precise scientific instruments in the high-end manufacturing industry, the electron impact ionization detector comprises a base station, a dustproof cover is mounted at the top of the base station, an ionization chamber is mounted at one end of the top of the base station, a repulsion pole is movably connected in an inner cavity of the ionization chamber, and a chromatographic column is mounted at the top of the ionization chamber; the opposite sides of the inner cavities of the first installation assembly and the second installation assembly are respectively provided with a bias lens, a focusing lens, a cooperation lens and a plate bias lens. The top of the base station is respectively provided with a quadrupole rod mass analyzer and an electron multiplier. The electron impact ionization detector for chromatography provided by the invention is a universal detector, can ensure that all ionized ions directly reach the detector through passing, ensures that compound information of a sample to be detected is not lost to the greatest extent, and is high in sensitivity, complete in information and high in response speed; the linear range of the electron multiplier is wide, and positive ions or negative ions or positive and negative ion alternate detection can be carried out.

Description

Technical Field

[0001] The invention relates to the field of high-end manufacturing precision scientific instruments, and in particular to an electron bombardment ionization detector for chromatography. Background Art

[0002] Common ionization detectors include FID (hydrogen flame ionization detector) and PID (photoionization detector). The basic principle of FID is as follows: FID detector is a highly sensitive general-purpose detector with the characteristics of high sensitivity, wide linear range, and fast response. It mainly responds to volatile organic compounds and can be used to detect sodium cyclamate, dehydroacetic acid, parabens, solvent No. 6, methanol, tert-amyl alcohol, propylene glycol, ethyl acetate, ethyl hexanoate, n-amyl acetate, etc.

[0003] However, it has low sensitivity or no response to inorganic gases, water, carbon tetrachloride and other substances with little or no hydrogen, which means that it cannot be used to detect these types of compounds, limiting its application in certain specific analyses. Its working principle is based on the chemical ionization process of organic matter in a hydrogen-air flame. When the carrier gas containing organic matter is ejected from the nozzle into the flame, the organic matter is cracked into free radicals at high temperature. These free radicals react with oxygen or molecular oxygen in the flame to generate positive ions and electrons. Under the action of the electric field, the positive ions and electrons move toward the two poles in a directional manner to form a microcurrent. The size of the microcurrent is proportional to the amount of organic matter entering the flame. Therefore, the organic matter can be quantitatively analyzed by measuring the intensity of the microcurrent.

[0004] FID disadvantages: The hydrogen flame ionization detector needs to provide carrier gas, hydrogen and air at the same time. In order to improve the sensitivity and stability of the detector, high-purity carrier gas and hydrogen are required. The flow ratio of these three gases has a significant impact on the performance of the detector. The flow of these three gases needs to be accurately controlled, which increases the complexity of the operation. The detection process involves the use of hydrogen, which is flammable and explosive. Therefore, there are strict requirements on the explosion-proof performance of the equipment, which requires users to strictly abide by the operating procedures to ensure the safe operation of the equipment.

[0005] Basic working principle of PID: PID works based on the principle of photoionization. The concentration of gas is determined by measuring the ion concentration in the measured gas. When the high-energy ultraviolet light emitted by the sensor interacts with the molecules in the gas, the electrons in the gas molecules are excited to produce energy level transitions, generating negative electrons and forming positive ions that diffuse in the sensor. The current generated by the ions is collected and amplified by the detector, and the concentration of ppm or ppb is displayed on the instrument. Most gases have their specific ionization energy, which is expressed in electron volts. In the ionization chamber, the vacuum ultraviolet lamp is used to ionize the sample gas into charged ions. When the sample gas passes through the ionization chamber, all gases with ionization energy lower than the photon energy of the vacuum ultraviolet lamp will be ionized into ions and electrons by the ultraviolet lamp. PID technology is relatively mature for VOC detection, and the resolution of TVOC measurement can reach up to 1ppb, which fully meets the specified test accuracy requirements. By using ultraviolet light sources with different energies, it is possible to measure certain specific organic gases, such as styrene, benzene vapor, vinyl chloride, ethylene, pyruvic acid and methylene chloride. The ultraviolet light energy depends on the properties of the mixed gas in the bulb and the crystal material used in the bulb window.

[0006] PID disadvantages: PID is a very accurate and sensitive detector that can detect levels as low as ppm or even ppb. However, PID is not a selective detection instrument and its ability to distinguish different compounds is relatively poor. If the IP of the gas molecules to be detected is lower than the emission energy of the lamp, then the gas molecules can be ionized and the gas or vapor can be detected by PID. Otherwise, it cannot be detected. Therefore, it can generally detect compounds with ionization energy lower than 11.77eV.

[0007] Therefore, it is necessary to propose an electron bombardment ionization detector for chromatography to solve the above problems. Summary of the invention

[0008] The main purpose of the present invention is to provide an electron bombardment ionization detector for chromatography, which can effectively solve the problems in the background technology.

[0009] To achieve the above object, the technical solution adopted by the present invention is:

[0010] An electron bombardment ionization detector for chromatography, comprising a base, a dust cover is installed on the top of the base, an ionization chamber is installed at one end of the top of the base, a mounting plate is installed at one end of the inner cavity of the ionization chamber, a driving assembly is installed on the outer wall of the mounting plate, a repeller is movably connected in the inner cavity of the ionization chamber, and a chromatographic column is installed on the top of the ionization chamber;

[0011] A first mounting assembly and a second mounting assembly are respectively arranged on both sides of the top of the base close to one end of the ionization chamber, a bias lens, a focusing lens, a cooperative lens and a plate bias lens are respectively installed on the opposite sides of the inner cavity of the first mounting assembly and the second mounting assembly, and an adjustment assembly is arranged at the bottom of the plate bias lens;

[0012] A clamping block is movably connected to one side of the second mounting component close to the first mounting component, a clamping slot is provided on one side of the first mounting component close to the second mounting component, and a quadrupole mass analyzer and an electron multiplier are respectively installed on the top of the base.

[0013] Preferably, a sampler is installed at one end of the chromatographic column, a quantitative loop ten-way valve is installed on the outer wall of the sampler, the other end of the chromatographic column is installed on the top of the ionization chamber and communicated with its inner cavity, a driving motor is installed on the outer wall of the driving assembly, gears are installed on both sides of the inner cavity of the driving assembly, the two gears are meshed with each other, and the driving motor is installed on the outer wall of the gear on the right side through a first rotating shaft.

[0014] Preferably, a threaded rod is installed at one end of the left gear close to the ionization chamber, the repeller is threadedly connected to the outer wall of the threaded rod, and the repeller includes a repeller lens, a focusing lens, an exit lens, and a filament.

[0015] Preferably, a first rotating cylinder is installed on the outer wall of the adjusting component, the center of the bottom of the plate offset lens is movably connected in the inner cavity of the adjusting component, one end of the first rotating cylinder is installed on the bottom of the plate offset lens through a second rotating shaft, the bottom of the adjusting component is movably connected with a movable block, a second rotating cylinder is installed on the top of the side of the movable block, and the second rotating cylinder is installed on the bottom of the adjusting component through a third rotating shaft.

[0016] Preferably, movable grooves are symmetrically opened at the bottom of the opposite sides of the first mounting component and the second mounting component, the movable block is movably connected in the inner cavity of the movable groove, a servo motor is installed on the outer wall of the second mounting component, the screw rod is rotatably connected in the inner cavity of the movable groove, the servo motor is installed on the outer wall of the screw rod through a fourth rotating shaft, the movable block is threadedly connected to the outer wall of the screw rod, and the plate offset lens is movably connected in the inner cavity of the first mounting component and the second mounting component.

[0017] Preferably, the bottom of the second mounting component is installed on the top of the base, the first mounting component is plugged into the top of the base, there are three card slots and three card blocks, the sizes of the card blocks and card slots are adapted, and the card blocks are plugged into the inner cavity of the first mounting component through the card slots.

[0018] Preferably, a movable groove is provided on the outer wall of the second mounting assembly, a guide column is fixedly connected to the inner cavity of the movable groove, a spring is wound around the outer wall of the guide column, a handle is installed on the left side of the spring, the left side of the handle is installed on the right side of the block, the handle is movably connected in the inner cavity of the movable groove, and the handle and the block are both sleeved on the outer wall of the guide column.

[0019] Preferably, the repeller is used to release high-energy electrons through a filament to ionize sample molecules and convert the sample molecules into ion fragments, and the quadrupole mass analyzer achieves transmission focusing of the ion fragments through voltage control.

[0020] Compared with the prior art, the present invention provides an electron bombardment ionization detector for chromatography, which has the following beneficial effects:

[0021] 1. The chromatographic electron bombardment ionization detector has an adjustable linear ionization energy and is a universal detector that can ensure that all ionized ions pass directly to the detector, ensuring that the compound information of the sample to be tested is not lost to the greatest extent. At the same time, the detector has high sensitivity, complete information, and fast response speed. The electron multiplier has a wide linear range and can detect positive or negative ions or alternating positive and negative ions.

[0022] 2. The chromatogram uses an electron bombardment ionization detector. Its sample molecules are ionized in the ion source to form ion fragments. The ion fragments are formed into ion fragments through the combination effect of the lenses in the ion source and enter the quadrupole mass analyzer. The quadrupole mass analyzer uses a full-through transmission mode for the ion fragments to form focused ion flow fragments. After the ion flow fragments reach the electron multiplier, they are converted into total ion flow detection chromatograms of different samples through step-by-step amplification and signal collectors.

[0023] 3. The chromatograph uses an electron bombardment ionization detector. Through the ionization chamber, the sample molecules are ionized in the ion source to form ion fragments. The ion source includes a repeller, which includes a repeller lens, a focusing lens, an exit lens, and a filament. The filament releases high-energy electrons to ionize the sample molecules, and the sample molecules are converted into ion fragments.

[0024] 4. The chromatograph uses an electron bombardment ionization detector, which uses a quadrupole mass analyzer as an ion transmission channel. The voltage of the quadrupole mass analyzer can be controlled to achieve transmission focusing of ion fragments, thereby reducing the loss of ion fragments that reach the multiplier after the sample molecules are ionized in the ion source.

[0025] 5. The chromatographic electron bombardment ionization detector can drive the two gears to mesh with each other by starting the set drive motor, so as to drive the threaded rod, so that the repeller can move back and forth in the inner cavity of the ionization chamber. The position of the repeller can be adjusted according to the use requirements, based on which the accuracy and efficiency of the detection can be improved, and it can meet the detection of various materials.

[0026] 6. The electron bombardment ionization detector for chromatography can adjust the angle of the plate bias lens by starting the first rotating cylinder and the second rotating cylinder, thereby improving the working accuracy of the lens and adjusting the transmission direction and focusing effect of the ion fragments as required. At the same time, by starting the servo motor, the lead screw can be driven to rotate so that the movable block can be threadedly connected to it. At this time, the placement position of the plate bias lens can be controlled, and the transmission direction and focusing range of the ion fragments can be further adjusted.

[0027] 7. The chromatographic electron bombardment ionization detector is convenient for disassembly and assembly of the bias lens, the focusing lens and the cooperative lens through a detachable first mounting assembly, thereby facilitating maintenance and processing thereof. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is a schematic diagram of the overall structure of the present invention;

[0029] Figure 2 It is a structural schematic diagram of the top of the base platform of the present invention;

[0030] Figure 3 It is a structural schematic diagram of the ionization chamber of the present invention;

[0031] Figure 4 It is a schematic structural diagram of the biased lens of the present invention;

[0032] Figure 5 It is a schematic structural diagram of the plate-biased lens of the present invention;

[0033] Figure 6 It is a schematic structural diagram of the second installation component of the present invention.

[0034] In the figure: 1. base; 2. dust cover; 3. ionization chamber; 4. sampler; 5. chromatographic column; 6. drive assembly; 7. drive motor; 8. gear; 9. mounting plate; 10. repeller; 11. threaded rod; 12. first mounting assembly; 13. second mounting assembly; 14. bias lens; 15. focusing lens; 16. cooperative lens; 17. plate bias lens; 18. adjustment assembly; 19. first rotating cylinder; 20. movable block; 21. second rotating cylinder; 22. lead screw; 23. servo motor; 24. slot; 25. movable slot; 26. block; 27. movable slot; 28. guide column; 29. ​​spring; 30. handle; 31. electron multiplier; 32. quadrupole mass analyzer. DETAILED DESCRIPTION

[0035] In order to make the technical means, creative features, objectives and effects achieved by the present invention easy to understand, the present invention is further explained below in conjunction with specific implementation methods.

[0036] Embodiment 1:

[0037] like Figure 1-Figure 3 As shown, an electron bombardment ionization detector for chromatography comprises a base 1, a dust cover 2 is installed on the top of the base 1, an ionization chamber 3 is installed at one end of the top of the base 1, a mounting plate 9 is installed at one end of the inner cavity of the ionization chamber 3, a driving assembly 6 is installed on the outer wall of the mounting plate 9, a repeller 10 is movably connected in the inner cavity of the ionization chamber 3, a chromatographic column 5 is installed on the top of the ionization chamber 3, a sampler 4 is installed at one end of the chromatographic column 5, a quantitative loop ten-way valve is installed on the outer wall of the sampler 4, the other end of the chromatographic column 5 is installed on the top of the ionization chamber 3 and communicated with the inner cavity thereof, a driving motor 7 is installed on the outer wall of the driving assembly 6, gears 8 are installed on both sides of the inner cavity of the driving assembly 6, the two gears 8 are meshed with each other, the driving motor 7 is installed on the outer wall of the right gear 8 through a first rotating shaft, and the left gear 8 is installed on the outer wall of the right gear 8 through a first rotating shaft. A threaded rod 11 is installed at one end of the gear 8 close to the ionization chamber 3, and a repeller 10 is threadedly connected to the outer wall of the threaded rod 11. The repeller 10 includes a repeller lens, a focusing lens, an exit lens, and a filament. A first rotary cylinder 19 is installed on the outer wall of the adjustment component 18. The center of the bottom of the plate bias lens 17 is movably connected in the inner cavity of the adjustment component 18. One end of the first rotary cylinder 19 is installed at the bottom of the plate bias lens 17 through a second rotating shaft. A movable block 20 is movably connected to the bottom of the adjustment component 18. A second rotary cylinder 21 is installed on the top of the side of the movable block 20. The second rotary cylinder 21 is installed at the bottom of the adjustment component 18 through a third rotating shaft. The repeller 10 is used to release high-energy electrons through the filament to ionize the sample molecules and convert the sample molecules into ion fragments.

[0038] By starting the drive motor 7, the two gears 8 can be driven to mesh with each other, thereby driving the threaded rod 11, so that the repeller 10 can move back and forth in the inner cavity of the ionization chamber 3, so that the position of the repeller 10 can be adjusted according to the use requirements, based on which the accuracy and efficiency of the detection can be improved, and various materials can be tested.

[0039] Embodiment 2:

[0040] like Figure 1 , Figure 4 , Figure 5 As shown, an electron bombardment ionization detector for chromatography, a first mounting assembly 12 and a second mounting assembly 13 are respectively arranged on both sides of the top of a base 1 near one end of an ionization chamber 3, a bias lens 14, a focusing lens 15, a cooperative lens 16 and a plate bias lens 17 are respectively installed on the opposite sides of the inner cavities of the first mounting assembly 12 and the second mounting assembly 13, an adjustment assembly 18 is arranged at the bottom of the plate bias lens 17, movable grooves 25 are symmetrically opened at the bottoms of the opposite sides of the first mounting assembly 12 and the second mounting assembly 13, a movable block 20 is movably connected in the inner cavity of the movable groove 25, a servo motor 23 is installed on the outer wall of the second mounting assembly 13, a screw rod 22 is rotatably connected in the inner cavity of the movable groove 25, the servo motor 23 is installed on the outer wall of the screw rod 22 through a fourth rotating shaft, the movable block 20 is threadedly connected to the outer wall of the screw rod 22, and the plate bias lens 17 is movably connected in the inner cavities of the first mounting assembly 12 and the second mounting assembly 13;

[0041] By starting the first rotating cylinder 19 and the second rotating cylinder 21, the angle of the plate bias lens 17 can be adjusted, so as to improve the working accuracy of the lens, and the transmission direction and focusing effect of the ion fragments can be adjusted according to needs. At the same time, by starting the servo motor 23, the screw rod 22 can be driven to rotate so that the movable block 20 can be threadedly connected to it. At this time, the placement position of the plate bias lens 17 can be controlled, and the transmission direction and focusing range of the ion fragments can be further adjusted.

[0042] Embodiment three:

[0043] like Figure 1 , Figure 4 , Figure 6As shown, an electron bombardment ionization detector for chromatography, a second mounting component 13 is movably connected to a card block 26 on one side close to the first mounting component 12, a card slot 24 is provided on one side of the first mounting component 12 close to the second mounting component 13, a quadrupole mass analyzer 32 and an electron multiplier 31 are respectively installed on the top of the base 1, the bottom of the second mounting component 13 is installed on the top of the base 1, the first mounting component 12 is plugged into the top of the base 1, there are three card slots 24 and three card blocks 26, the sizes of the card blocks 26 and the card slots 24 are adapted, and the card blocks 26 The second mounting assembly 13 is inserted into the inner cavity of the first mounting assembly 12 through the card slot 24, and a movable slot 27 is opened on the outer wall of the second mounting assembly 13. A guide column 28 is fixedly connected in the inner cavity of the movable slot 27. A spring 29 is wound around the outer wall of the guide column 28. A handle 30 is installed on the left side of the spring 29. The left side of the handle 30 is installed on the right side of the card block 26. The handle 30 is movably connected in the inner cavity of the movable slot 27. The handle 30 and the card block 26 are both sleeved on the outer wall of the guide column 28. The quadrupole mass analyzer 32 realizes the transmission focusing effect of ion fragments through voltage control.

[0044] The detachable first mounting assembly 12 facilitates the disassembly and assembly of the bias lens 14, the focusing lens 15 and the cooperative lens 16, thereby facilitating their maintenance.

[0045] Its ionization energy is linearly adjustable, and it is a universal detector that can ensure that all ionized ions pass directly to the detector, ensuring that the compound information of the sample to be tested is not lost to the greatest extent. At the same time, the detector has high sensitivity, complete information, and fast response speed. The electron multiplier 31 has a wide linear range and can perform positive ion or negative ion or positive and negative ion alternation detection.

[0046] The sample molecules are ionized in the ion source to form ion fragments, and the ion fragments are formed into ion fragments through the lens combination effect in the ion source and enter the quadrupole mass analyzer 32. The quadrupole mass analyzer 32 adopts a full-through transmission mode for the ion fragments to form focused ion flow fragments. After the ion flow fragments reach the electron multiplier, they are converted into total ion flow detection chromatograms of different samples through step-by-step amplification and signal collectors.

[0047] Through the ionization chamber 3, the sample molecules are ionized in the ion source to form ion fragments. The ion source includes a repeller 10, which includes a repeller lens, a focusing lens, an exit lens, and a filament. The filament releases high-energy electrons to ionize the sample molecules, and the sample molecules are converted into ion fragments.

[0048] By using the quadrupole mass analyzer 32 as an ion transmission channel, the transmission focusing effect on the ion fragments can be achieved by controlling the voltage of the quadrupole mass analyzer 32, thereby reducing the loss of ion fragments that reach the multiplier after the sample molecules are ionized in the ion source.

[0049] It should be noted that the present invention is an electron bombardment ionization detector for chromatography. When in use, the sample enters the chromatographic column 5 from the sampler 4, and the sample is separated in the chromatographic column 5. Different substances have different retention times in the chromatogram, and leave the chromatographic column 5 in turn and enter the ionization chamber 3. The filament at the repeller 10 is started, and the material collides with the electron beam emitted by the filament to ionize and transform the neutral molecules into charged ion flow. Under the action of the electric field, the ion flow passes through the bias lens 14, the focusing lens 15, the cooperative lens 16, the plate bias lens 17 and the quadrupole mass analyzer 32 for collimation and focusing, and then flies into the electron multiplier 31 to form an electrical signal. Through digital-to-analog conversion, the electrical signal is converted into a digital signal, which is processed by software to become a chromatogram.

[0050] The above shows and describes the basic principles and main features of the present invention and the advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. An electron bombardment ionization detector for chromatography, comprising a base station (1), characterized in that: A dust cover (2) is installed on the top of the base (1); an ionization chamber (3) is installed at one end of the top of the base (1); a mounting plate (9) is installed at one end of the inner cavity of the ionization chamber (3); a driving assembly (6) is installed on the outer wall of the mounting plate (9); a repeller (10) is movably connected in the inner cavity of the ionization chamber (3); and a chromatographic column (5) is installed on the top of the ionization chamber (3); A first mounting assembly (12) and a second mounting assembly (13) are respectively arranged on both sides of the top of the base (1) close to one end of the ionization chamber (3); a bias lens (14), a focusing lens (15), a cooperative lens (16) and a plate bias lens (17) are respectively arranged on the opposite sides of the inner cavities of the first mounting assembly (12) and the second mounting assembly (13); and an adjustment assembly (18) is arranged at the bottom of the plate bias lens (17); A clamping block (26) is movably connected to a side of the second mounting component (13) close to the first mounting component (12); a clamping slot (24) is provided on a side of the first mounting component (12) close to the second mounting component (13); and a quadrupole mass analyzer (32) and an electron multiplier (31) are respectively installed on the top of the base (1).

2. The electron impact ionization detector for chromatography according to claim 1, characterized in that: A sampler (4) is installed at one end of the chromatographic column (5), and a quantitative loop ten-way valve is installed on the outer wall of the sampler (4). The other end of the chromatographic column (5) is installed on the top of the ionization chamber (3) and communicates with its inner cavity. A drive motor (7) is installed on the outer wall of the drive component (6), and gears (8) are installed on both sides of the inner cavity of the drive component (6). The two gears (8) are meshed with each other, and the drive motor (7) is installed on the outer wall of the gear (8) on the right side through a first rotating shaft.

3. The electron impact ionization detector for chromatography according to claim 2, characterized in that: A threaded rod (11) is installed at one end of the left gear (8) close to the ionization chamber (3), and the repeller (10) is threadedly connected to the outer wall of the threaded rod (11). The repeller (10) includes a repeller lens, a focusing lens, an exit lens, and a filament.

4. The electron impact ionization detector for chromatography according to claim 1, characterized in that: A first rotating cylinder (19) is installed on the outer wall of the adjustment component (18); the center of the bottom of the plate-biased lens (17) is movably connected in the inner cavity of the adjustment component (18); one end of the first rotating cylinder (19) is installed on the bottom of the plate-biased lens (17) via a second rotating shaft; a movable block (20) is movably connected to the bottom of the adjustment component (18); a second rotating cylinder (21) is installed on the top of the side of the movable block (20); and the second rotating cylinder (21) is installed on the bottom of the adjustment component (18) via a third rotating shaft.

5. The electron impact ionization detector for chromatography according to claim 4, characterized in that: A movable groove (25) is symmetrically provided at the bottom of the opposite side of the first mounting component (12) and the second mounting component (13); the movable block (20) is movably connected in the inner cavity of the movable groove (25); a servo motor (23) is installed on the outer wall of the second mounting component (13); the screw rod (22) is rotatably connected in the inner cavity of the movable groove (25); the servo motor (23) is installed on the outer wall of the screw rod (22) through a fourth rotating shaft; the movable block (20) is threadedly connected to the outer wall of the screw rod (22); and the plate bias lens (17) is movably connected in the inner cavity of the first mounting component (12) and the second mounting component (13).

6. The electron impact ionization detector for chromatography according to claim 1, characterized in that: The bottom of the second mounting component (13) is mounted on the top of the base (1), and the first mounting component (12) is plugged into the top of the base (1). There are three card slots (24) and three card blocks (26), and the sizes of the card blocks (26) and the card slots (24) are adapted to each other. The card blocks (26) are plugged into the inner cavity of the first mounting component (12) through the card slots (24).

7. The electron impact ionization detector for chromatography according to claim 1, characterized in that: The outer wall of the second mounting assembly (13) is provided with a movable groove (27), a guide column (28) is fixedly connected to the inner cavity of the movable groove (27), a spring (29) is wound around the outer wall of the guide column (28), a handle (30) is installed on the left side of the spring (29), the left side of the handle (30) is installed on the right side of the block (26), the handle (30) is movably connected to the inner cavity of the movable groove (27), and the handle (30) and the block (26) are both sleeved on the outer wall of the guide column (28).

8. The electron impact ionization detector for chromatography according to claim 1, characterized in that: The repeller (10) is used to release high-energy electrons through a filament to ionize sample molecules and convert the sample molecules into ion fragments. The quadrupole mass analyzer (32) realizes a transmission focusing effect on the ion fragments through voltage control.

Images