Ion trap demonstration device and method

Abstract

This invention discloses a demonstration tool and method for ion trapping and quadrupole mass spectrometry principles. A segmented trap assembly is fixedly mounted on a base, and a sample preparation component for storing sample particles is inserted within the segmented trap assembly. One end of the sample preparation component is connected to a gas pump. The segmented trap assembly includes four segmented rods arranged in a cross shape, each with a corresponding radio frequency electric field and DC field applied. The sample preparation component is located between the four segmented rods and is equidistant from them. Each segmented rod includes a radio frequency electrode, with a first cap electrode and a second cap electrode fixedly connected to its two ends. One end of the radio frequency electrode is electrically connected to a radio frequency electrode fixedly mounted on the first cap electrode. This invention can be used to demonstrate both the trapping principle of an ion trap and the mass selection principle of a quadrupole mass spectrometer. It has advantages such as high feasibility, simple operation, and low manufacturing cost, thus making it possible to conduct more widespread teaching demonstration experiments.

Description

Technical Field

[0001] This invention belongs to the technical field of teaching aids and related equipment, and particularly relates to a teaching aid and demonstration method for the principle of ion trapping and quadrupole mass spectrometry. Background Technology

[0002] Cold ions are increasingly recognized as an important carrier of quantum information research, while quadrupole mass spectrometers, as important equipment in the field of mass spectrometry, have been widely used. Linear ion traps and quadrupole mass spectrometers have the same basic structure and similar working principles. Studying these two devices together can promote students' integration of knowledge. Because ion traps and mass spectrometers target microscopic ions, which cannot be observed with the naked eye, they require high-magnification imaging systems and related laser technologies to indirectly observe. Furthermore, traditional ion trap and mass spectrometer systems require vacuuming the background environment to avoid collisions with ions by background gas molecules. Additionally, the ions used in traditional ion trap and quadrupole mass spectrometer systems generally require atomic ionization devices, typically photoionization or electron collision ionization, which increases system complexity and operating costs. Currently, ion trap systems are primarily found in research laboratories, and constructing a complete optically detectable ion trap system is quite expensive. Traditional quadrupole mass spectrometers are also mainly used in detection laboratories. According to the applicant's research, devices demonstrating the working principles of both systems do not currently exist.

[0003] Therefore, this application designs a demonstration tool and demonstration method for ion trapping and quadrupole mass spectrometry to solve the above-mentioned technical problems. Summary of the Invention

[0004] To address the aforementioned technical problems, this invention proposes a demonstration tool and method for illustrating the principles of ion trapping and quadrupole mass spectrometry.

[0005] To achieve the above objectives, the present invention provides a demonstration teaching aid for ion trap confinement and quadrupole mass spectrometry principles, including a base on which a segmented trap assembly is fixedly mounted. A sample preparation assembly is disposed inside the segmented trap assembly and is used to store sample particles. One end of the sample preparation assembly extends out of the segmented trap assembly and is connected to a gas pump.

[0006] The segmented trap assembly includes four segmented rods arranged in a cross shape, each segment of which is subjected to a corresponding radio frequency electric field and a DC electric field; the sample preparation assembly is located between the four segmented rods and is equally spaced from them.

[0007] The segmented rod includes a radio frequency pole, with a first cap pole and a second cap pole fixedly connected to its two ends respectively, and one end of the radio frequency pole being electrically connected to a radio frequency electrode fixedly installed on the first cap pole.

[0008] Preferably, the first cap rod and the second cap rod are hollow structures, the radio frequency electrode is fixedly connected to the end of the first cap rod away from the radio frequency electrode, the radio frequency electrode is a solid structure that is thick in the middle and thin at both ends, and one end of the radio frequency electrode passes through the first cap rod and is electrically connected to the radio frequency electrode.

[0009] Preferably, the outer diameters of the first cap rod, the second cap rod, the radio frequency electrode, and the middle section of the radio frequency pole are the same; insulating rings are respectively provided between the radio frequency pole and the first cap rod and the second cap rod, and between the first cap rod and the radio frequency electrode.

[0010] Preferably, a radio frequency electric field is applied to the radio frequency electrode, and a superposition field of radio frequency electric field and DC electric field is applied to the first cap rod and the second cap rod.

[0011] Preferably, the sample preparation assembly includes a glass tube containing sample particles, the glass tube being located at the center of the four segmented rods, and the two ends of the glass tube extending beyond the two ends of the segmented rods and respectively sealed and fixedly installed with end caps; an end cap is fitted and fixedly connected to an air pump cover connected to an air pipe, and the end cap corresponding to the air pump cover has several through holes evenly distributed on it.

[0012] Preferably, the top of the base is fixedly installed with two symmetrically arranged first mounting seats and two symmetrically arranged second mounting seats; the two second mounting seats are located between the two first mounting seats; both ends of the glass tube pass through the two first mounting seats respectively and are fixedly connected to the first mounting seats; the first cap rod and the second cap rod pass through a second mounting seat respectively and are fixedly connected to the second mounting seat; a first buckle is fixedly installed on the first mounting seat, and the first buckle fixes the glass tube on the first mounting seat.

[0013] Preferably, a second buckle with the same structure and compatible with it is fixedly installed at the top of the second mounting base; mounting holes adapted to the segment rod are respectively opened on the second mounting base and the second buckle, and the segment rod passes through the mounting holes and is fixedly connected to the mounting holes; a semi-circular through groove adapted to the glass tube is opened at the top of the second mounting base and the bottom of the second buckle, and the two through grooves are correspondingly arranged; the glass tube passes through the through groove and is fixedly connected to the through groove; a plurality of tightening bolts are threadedly connected to the side walls of the second mounting base and the second buckle, and the tightening bolts abut against the segment rod.

[0014] Preferably, the glass tube has a rough structure on one half and a smooth structure on the other half along the radial direction. The rough structure is used to rub against the sample particles to make the sample particles statically charged, while the smooth structure is used to enhance light transmittance and facilitate observation of experimental results.

[0015] Preferably, the sample particles are made of metal and vary in size, with multiple sizes available.

[0016] A method for demonstrating the principle of ion trapping and quadrupole mass spectrometry includes the following steps:

[0017] Step 1: Sample loading; Load sample particles of different sizes into the sample preparation assembly;

[0018] Step 2: Triboelectric charging; Connect the sample preparation assembly to the air pump, turn on the air pump to supply air to the sample preparation assembly to make the sample particles move randomly, thereby generating triboelectric charge;

[0019] Step 3: Set up the confinement field; stop the gas pump supply, and then apply the confinement field to the sample particles inside the glass tube;

[0020] Step 4: Principle Demonstration; Demonstrate the trapping principle of the ion trap and the mass selection principle of the quadrupole mass spectrometer according to different needs;

[0021] Step 5: Post-experiment processing; Properly dispose of the experimental equipment after the demonstration.

[0022] Compared with existing technologies, this invention has the following advantages and technical effects: When using this device, sample particles are loaded into the sample preparation assembly, and air is pumped into the sample preparation assembly to cause random frictional charging between the sample particles and the sample preparation assembly. Then, an external electric field is connected through the segmented trap assembly to achieve ion trap trapping of the charged sample particles, demonstrating the principle of ion trap trapping. At the same time, different electric fields can be applied through the segmented trap assembly to perform mass selection on sample particles of different sizes, demonstrating the mass selection principle of a quadrupole mass spectrometer. The four segmented rods of the segmented trap assembly are evenly distributed around the sample preparation assembly, which facilitates the uniform application of electric fields to the sample particles. The segmented rods are divided into a first cap rod, a radio frequency rod, and a second cap rod, which facilitates the application of different electric fields to the segmented rods and the adjustment of different combinations of electric and radio frequency fields, making the demonstration more applicable.

[0023] This invention can be used to demonstrate both the trapping principle of ion traps and the mass selection principle of quadrupole mass spectrometers. It has the advantages of high feasibility, simple operation and low manufacturing cost, thus making it possible to carry out its teaching demonstration experiments more widely. Attached Figure Description

[0024] The accompanying drawings, which form part of this application, are used to provide a further understanding of this application. The illustrative embodiments and descriptions of this application are used to explain this application and do not constitute an undue limitation of this application. In the drawings:

[0025] Figure 1 Axial view of the teaching aid demonstrating the principles of ion trap trapping and quadrupole mass spectrometry of this invention;

[0026] Figure 2 This is a side view of the teaching aid demonstrating the principles of ion trap trapping and quadrupole mass spectrometry of the present invention.

[0027] Figure 3 This is a diagram illustrating the pole markings of the present invention;

[0028] Figure 4 This is a schematic diagram of the wiring for the radio frequency voltage signal and the DC voltage signal of the present invention;

[0029] In the figure: 1. Base; 2. First mounting base; 3. First snap-fit; 4. End cap; 5. Glass tube; 6. Radio frequency electrode; 7. Insulating ring; 8. Second mounting base; 9. Second snap-fit; 10. First cap rod; 11. Radio frequency electrode rod; 12. Second cap rod; 13. Air pump cover; 14. Air tube; 15. Segmented trap assembly; 16. Sample preparation assembly; 17. Sample particles. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] Reference Figure 1-4 As shown, this embodiment provides a teaching aid for demonstrating the principles of ion trap confinement and quadrupole mass spectrometry, including a base 1, on which a segmented trap assembly 15 is fixedly installed, and a sample preparation assembly 16 is inserted inside the segmented trap assembly 15. The sample preparation assembly 16 is used to store sample particles 17; one end of the sample preparation assembly 16 extends out of the segmented trap assembly 15 and is connected to a gas pump.

[0033] The segmented trap assembly 15 includes four segmented rods arranged in a cross shape, each segment of which is subjected to a corresponding radio frequency electric field and a DC electric field; the sample preparation assembly 16 is located between the four segmented rods and is equally spaced from the four segmented rods.

[0034] The electrode includes a radio frequency electrode 11, with a first cap electrode 10 and a second cap electrode 12 fixedly connected to its two ends respectively. One end of the radio frequency electrode 11 is electrically connected to a radio frequency electrode 6 fixedly installed on the first cap electrode 10.

[0035] When using this device, sample particles 17 are loaded into the sample preparation assembly 16. Air is pumped into the sample preparation assembly 16, causing random frictional charging between the sample particles 17 and the assembly. An external electric field is then applied through the segmented trap assembly 15 to trap the charged sample particles 17, demonstrating the ion trap principle. Simultaneously, different electric fields can be applied through the segmented trap assembly 15 to perform mass selection on sample particles 17 of different sizes, demonstrating the mass selection principle of a quadrupole mass spectrometer. The four segmented rods of the segmented trap assembly 15 are evenly distributed around the sample preparation assembly 16, facilitating the uniform application of an electric field to the sample particles 17. The segmented rods are divided into a first cap rod 10, an RF rod 11, and a second cap rod 12, allowing for the application of different electric fields and the adjustment of different combinations of electric and RF fields, thus broadening the applicability of the demonstration. This invention can be used to demonstrate the trapping principle of ion traps and the mass selection principle of quadrupole mass spectrometers. It has the advantages of high feasibility, simple operation and low manufacturing cost, which makes it possible to carry out its teaching demonstration experiments more widely.

[0036] Furthermore, the base 1 of this application is made of stainless steel and has a downward-opening through hole for fixing the entire device.

[0037] In a further optimized design, the first cap rod 10 and the second cap rod 12 are hollow structures. The radio frequency electrode 6 is fixed to the end of the first cap rod 10 away from the radio frequency electrode 11. The radio frequency electrode 11 is a solid structure that is thick in the middle and thin at both ends. One end of the radio frequency electrode 11 passes through the first cap rod 10 and is electrically connected to the radio frequency electrode 11. The outer diameters of the middle sections of the first cap rod 10, the second cap rod 12, the radio frequency electrode 6, and the radio frequency electrode 11 are the same. Insulating rings 7 are respectively provided between the radio frequency electrode 11 and the first cap rod 10 and the second cap rod 12, and between the first cap rod 10 and the radio frequency electrode 6. A radio frequency electric field is applied to the radio frequency electrode 6, and a superposition field of the radio frequency electric field and the DC electric field is applied to the first cap rod 10 and the second cap rod 12. In this embodiment, the segmented trap assembly 15 has a three-segment structure. Each segment has four identical poles arranged in a cross shape. The eight poles at both ends are four first cap poles 10 and four second cap poles 12, and the four poles in the middle are radio frequency poles 11. The radio frequency poles 11 in the middle and the first cap poles 10 and second cap poles 12 at both ends are separated by an insulating ring 7 composed of insulating ceramic gaskets. The first cap poles 10 and second cap poles 12 at both ends are hollow structures. The radio frequency poles 11 in the middle are solid structures that are thicker in the middle and thinner at both ends. One end of the poles extends beyond the first cap poles 10 and connects to the radio frequency electrode 6. The first cap poles 10, second cap poles 12, radio frequency poles 11 and radio frequency electrode 6 are all made of 316 stainless steel and have the same diameter. A radio frequency electric field is applied to the radio frequency electrode 6, and a superposition field of radio frequency electric field and DC electric field is applied to the first cap poles 10 and second cap poles 12.

[0038] Further optimizing the scheme, the sample preparation component 16 includes a glass tube 5 containing sample particles 17. The glass tube 5 is located at the center of four segmented rods. Both ends of the glass tube 5 pass over the ends of the segmented rods and are respectively sealed and fixedly installed with end caps 4. The end caps 4 are fitted and fixedly connected to the air pump cover 13 connected to the air pipe 14. The end caps 4, which are corresponding to the air pump cover 13, have several through holes evenly distributed on them. The glass tube 5 has a rough structure on one half and a smooth structure on the other half along the radial direction. The rough structure is used to rub against the sample particles 17 to make the sample particles 17 statically charged, and the smooth structure is used to enhance light transmittance and facilitate the observation of experimental results. The sample preparation assembly 16 is a glass tube 5 with end caps 4 at both ends. The glass tube 5 is placed at the center of the segment. The end caps 4 at both ends of the glass tube 5 are used to create a sealed environment. The end caps 4 have some holes evenly distributed on them. The end caps 4 can be wrapped by a funnel-shaped air pump cover 13 and connected to an air pump through an air pipe 14. The glass tube 5 has a rough structure on one half and a smooth structure on the other half along the radial direction. The rough structure is used to rub against the sample particles 17 to make the sample static electricity, while the smooth structure can enhance the light transmittance, making it easier for the experimenter to observe the experimental results.

[0039] Further optimization of the design: two symmetrically arranged first mounting seats 2 and two symmetrically arranged second mounting seats 8 are fixedly installed at the top of the base 1; the two second mounting seats 8 are located between the two first mounting seats 2; the two ends of the glass tube 5 pass through the two first mounting seats 2 respectively and are fixedly connected to the first mounting seats 2; the first cap rod 10 and the second cap rod 12 pass through a second mounting seat 8 respectively and are fixedly connected to the second mounting seat 8; a first buckle 3 is fixedly installed on the first mounting seat 2, and the first buckle 3 fixes the glass tube 5 on the first mounting seat 2. The first mounting base 2 and the second mounting base 8 are fixedly mounted on the base 1 to fix the sample preparation assembly 16 and the segmented trap assembly 15. The first mounting base 2 needs to be used in conjunction with the first buckle 3 to fix the glass tube 5. The first mounting base 2 and the first buckle 3 have the same diameter, which is slightly larger than the diameter of the glass tube 5. The cut of the first mounting base 2 is exactly a semicircle, while the cut of the first buckle 3 is slightly smaller than a semicircle. The glass tube 5 is fixed in place. Since the length of the segmented trap assembly 15 is less than that of the glass tube 5, the two second mounting bases 8 are located between the two first mounting bases 2 to fix and install the segmented trap assembly 15.

[0040] Further optimizing the design, a second buckle 9 with the same structure and compatible design is fixedly installed on the top of the second mounting base 8; mounting holes adapted to the segment rod are respectively opened on the second mounting base 8 and the second buckle 9, and the segment rod passes through the mounting holes and is fixedly connected to the mounting holes; semi-circular through grooves adapted to the glass tube 5 are opened at the top of the second mounting base 8 and the bottom of the second buckle 9, and the two through grooves are set accordingly; the glass tube 5 passes through the through grooves and is fixedly connected to the through grooves; several tightening bolts are threadedly connected to the side walls of the second mounting base 8 and the second buckle 9, and the tightening bolts abut against the segment rod. The second buckle 9 and the second mounting base 8 have the same structure and are fixedly connected. The contact surfaces of the two are respectively provided with semi-circular through grooves, and the two through grooves form a complete circle to facilitate the passage of the glass tube 5 and support the glass tube 5. The second mounting base 8 and the second buckle 9 are respectively provided with two symmetrical mounting holes. The diameter of the mounting holes is slightly larger than that of the segment rod, and its shape is a 3 / 4 circle. The missing part is connected to the through groove used to install the glass tube 5. The first cap rod 10 and the second cap rod 12 are fixed by the second mounting base 8 and the second buckle 9 at both ends to achieve an equidistant arrangement with the glass tube 5. The tightening bolts on both sides are used to tighten against the outer wall of the segment rod after installation and adjustment, so as to play a fixing role.

[0041] Furthermore, the first mounting base 2, the second mounting base 8, the first clip 3, and the second clip 9 are all made of alumina insulating ceramic material to prevent them from affecting the electric field on the segment rod and the glass tube 5.

[0042] Further optimization of the scheme: the sample particles 17 are made of metal and vary in size. In this embodiment, the sample particles 17 are triboelectrically charged inside the glass tube 5, and the amount of charge varies. Given the inability to directly observe traditional microscopic ions with the naked eye, this device uses electrostatically charged sample particles 17 to replace microscopic ions, allowing the experimenter to directly observe the trapping and selection effects of ions. Furthermore, compared to background gas molecules, the visible sample particles 17 have a significant mass advantage, and their motion is largely unaffected by the background gas. Therefore, using sample particles 17 to replace traditional ions perfectly avoids the need for vacuuming.

[0043] like Figure 3 The diagram shows the three-segment structure of the segmented trap assembly 15. Each segment is numbered from left to right as A, B, and C. A is the first cap electrode 10, B is the RF electrode 11, and C is the second cap electrode 12. Each segment has four electrodes. Each electrode in segments A and C requires a DC electric field and an RF electric field, respectively, while each electrode in segment B requires an RF electric field. This embodiment designs a voltage application circuit, see [link to circuit]. Figure 4 As shown, the multi-channel DC voltage source outputs seven DC voltages, each with a corresponding operational effect: the voltage output by channel U1 achieves axial compression of sample particle 17; the voltage output by channel U2 achieves axial leftward pushing of sample particle 17; the voltage output by channel U3 achieves axial rightward pushing of sample particle 17; the voltage output by channel U4 achieves upward pushing of sample particle 17; the voltage output by channel U5 achieves downward pushing of sample particle 17; and the voltages output by channels U6 and U7 achieve radial diagonal compression of sample particle 17. To achieve the corresponding operational effects, the voltage applied to each pole is the superposition of the output voltages from multiple channels. Figure 4 As shown, the DC voltage applied to each pole in segments A and C is the sum of the voltages from the four channels, implemented using an adder circuit. The dual-channel RF signal source outputs two RF signals of equal amplitude and opposite phase. RF signals with zero phase are applied to A1, B1, C1 and A4, B4, C4, while RF signals with a phase of π are applied to the remaining six poles. The RF signals and DC signals are also superimposed using an adder. To avoid mutual interference, an inductor is connected in series in the DC circuit, and a capacitor is connected in series in the RF circuit. The values ​​of the capacitor and inductor are related to the RF frequency.

[0044] A method for demonstrating the principle of ion trapping and quadrupole mass spectrometry includes the following steps:

[0045] Step 1: Sample loading; Load sample particles 17 of different sizes into sample preparation assembly 16; Remove sample glass tube 5, load sample particles 17 of different sizes into it, and seal it with end caps 4 at both ends; One of the end caps 4 is provided with several vent holes.

[0046] Step 2: Triboelectric charging; Connect the sample preparation assembly 16 to the air pump, turn on the air pump to supply air to the sample preparation assembly 16 to make the sample particles 17 move randomly, thereby becoming triboelectrically charged; Cover the perforated end cap 4 with a funnel-shaped air pump cap 13, and connect the air pipe 14 to the air pump. The air pump can be manual or electric. By pumping air into the glass tube 5, the sample particles 17 are made to move randomly inside the glass tube 5, thereby rubbing against the frosted glass part of the glass tube 5, and thus becoming charged; If the sample particles 17 are all blown to one end of the glass tube 5, the two end caps 4 need to be interchanged, and the air pump needs to pump air from the other end, so that most of the particles are in the middle section of the glass tube 5.

[0047] Step 3: Set up the confinement field; stop the gas pump supply, and then apply the confinement field to the sample particles 17 in the glass tube 5; set the initial voltage of U1 to any value of about 2V, set the initial values ​​of other DC voltages to 0, and turn on the power output button to enable successful signal output; set the initial amplitude (peak-to-peak value) of the radio frequency electric field to 200V, the initial value of the radio frequency frequency to 10MHz, and turn on the radio frequency signal source output button to enable successful signal output;

[0048] Step Four: Principle Demonstration; Demonstrate the trapping principle of the ion trap and the mass selection principle of the quadrupole mass spectrometer according to different needs; Steps One to Three are general steps for demonstrating the trapping principle of the ion trap and the mass selection principle of the quadrupole mass spectrometer; The specific steps for demonstrating the trapping principle of the ion trap are as follows:

[0049] Adjusting the radio frequency field: Keeping the radio frequency field amplitude constant, gradually decrease the radio frequency and observe the condition of sample particles 17. It can be seen that initially all sample particles 17 are sunk at the lower end of glass tube 5. As the radio frequency decreases, some small particles slowly float up. Continuing to decrease the radio frequency, small particles slowly fall while large particles slowly float up, and the particles that can be floated become larger and larger until all particles can no longer float. All the floated particles are basically located at the center of the radio frequency electrode 11, which is actually trapped by the electric field. Since whether a particle can be successfully trapped in the ion trap depends on its charge-to-mass ratio, sample particles 17 with similar friction conditions have basically the same charge, while particles with different sizes have a relatively large difference in mass. Therefore, when the radio frequency field is changed, particles with different charge-to-mass ratios (particle sizes) will be trapped. This demonstration illustrates the principle of ion trap trapping.

[0050] Adjusting the DC electric field: When sample particle 17 is successfully trapped, keep the magnitude and frequency of the radio frequency field constant, and change the magnitudes of U1, U2, U3, U4, U5, U6, and U7 respectively, and observe the position changes of sample particle 17; it can be found that as the voltage of each output channel of the multi-channel DC voltage source gradually increases, the corresponding position change of sample particle 17 can be observed; this demonstration process shows the method of adjusting the ion position in the ion trap experiment;

[0051] The specific steps for demonstrating the mass selection principle of a quadrupole mass spectrometer are as follows:

[0052] Adjusting the radio frequency field: Keep the radio frequency field amplitude constant and gradually decrease the radio frequency, and observe the condition of sample particles 17; it can be found that at the beginning, all sample particles 17 are sunk at the bottom of the glass tube 5. As the radio frequency decreases, some small particles slowly float up. Continue to decrease the radio frequency, and the small particles slowly fall down while the large particles slowly float up, and the particles that can be floated up are getting bigger and bigger.

[0053] Mass selection: Gradually increase the voltages U2 and U3 until they are equal, then adjust the voltage U1 to 0. At this point, sample particle 17 is stably trapped in the center of glass tube 5. Suddenly turn off the voltage output of U3, keeping U2 unchanged. It is observed that sample particle 17 flies to the left side of glass tube 5, and some particles even escape from the left port. Suddenly turn off the voltage output of U2, keeping U3 unchanged. It is observed that sample particle 17 flies to the right side of glass tube 5, and some particles even escape from the right port. The sample particle 17 that escaped is the sample particle 17 that was stably trapped before the voltage was turned off. By adjusting the radio frequency field, different particles can be trapped. Turning off the cap voltage on one side can select the specific sample particle 17. This process demonstrates the mass selection principle of a quadrupole mass spectrometer.

[0054] It should be noted that the sample particles 17 that can be trapped are relatively small and their size may not be distinguishable to the naked eye. In this case, sample particles 17 of different sizes can be tested separately, the corresponding radio frequency amplitude and frequency can be recorded, and the results can be analyzed and compared.

[0055] It should be noted that the demonstration of the trapping principle of the ion trap and the demonstration of the mass selection principle of the quadrupole mass spectrometer are different working processes and need to be demonstrated separately.

[0056] Step 5: Post-experiment processing; Properly dispose of the experimental equipment after the demonstration. After the demonstration, disconnect the power to the device, then remove and recover the sample particles 17 from glass tube 5, and clean glass tube 5 for future use.

[0057] In the description of this invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this invention, and are not intended to indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0058] The embodiments described above are merely preferred embodiments of the present invention and are not intended to limit the scope of the present invention. Various modifications and improvements made by those skilled in the art to the technical solutions of the present invention without departing from the spirit of the present invention should fall within the protection scope defined by the claims of the present invention.

Claims

1. An ion-trap confinement and quadrupole mass-spectrometry principle demonstration kit, characterized in that: Includes a base (1), on which a segmented trap assembly (15) is fixedly installed, and a sample preparation assembly (16) is inserted inside the segmented trap assembly (15). The sample preparation assembly (16) is used to store sample particles (17); one end of the sample preparation assembly (16) extends out of the segmented trap assembly (15) and is connected to an air pump. The segmented trap assembly (15) includes four segmented rods arranged in a cross shape, each segment of which is subjected to a corresponding radio frequency electric field and a DC electric field; the sample preparation assembly (16) is located between the four segmented rods and is equally spaced from the four segmented rods. The segmented rod includes a radio frequency pole (11), with a first cap pole (10) and a second cap pole (12) fixedly connected to both ends of the radio frequency pole (11), and one end of the radio frequency pole (11) is electrically connected to a radio frequency electrode (6) fixedly installed on the first cap pole (10). The first cap rod (10) and the second cap rod (12) are hollow structures. The radio frequency electrode (6) is fixed to the end of the first cap rod (10) away from the radio frequency electrode (11). The radio frequency electrode (11) is a solid structure that is thick in the middle and thin at both ends. One end of the radio frequency electrode (11) passes through the first cap rod (10) and is electrically connected to the radio frequency electrode (6). A radio frequency electric field is applied to the radio frequency electrode (6), and a superposition field of radio frequency electric field and DC electric field is applied to the first cap rod (10) and the second cap rod (12); The sample preparation assembly (16) includes a glass tube (5) containing sample particles (17). The glass tube (5) is located at the center of the four segmented rods. Both ends of the glass tube (5) extend beyond the ends of the segmented rods and are respectively sealed and fixedly installed with end caps (4). One of the end caps (4) is sleeved and fixedly connected to the air pump cover (13) connected to the air pipe (14). The end cap (4) corresponding to the air pump cover (13) has several through holes evenly distributed on it. The glass tube (5) has a rough structure on one half and a smooth structure on the other half along the radial direction. The rough structure is used to rub against the sample particles (17) to make the sample particles (17) carry static electricity, and the smooth structure is used to enhance light transmittance and facilitate the observation of experimental results. The demonstration method of the aforementioned ion trap trapping and quadrupole mass spectrometry principle demonstration teaching aid includes the following steps: Step 1: Sample loading; Load sample particles (17) of different sizes into the sample preparation assembly (16); Step 2: Triboelectric charging; Connect the sample preparation component (16) to the air pump, turn on the air pump to circulate air to the sample preparation component (16) to make the sample particles (17) move randomly, and thus become triboelectrically charged; Step 3: Set up the confinement field; stop the gas supply from the gas pump, and then apply the confinement field to the sample particles (17) in the glass tube (5); Step 4: Principle Demonstration; Demonstrate the trapping principle of the ion trap and the mass selection principle of the quadrupole mass spectrometer according to different needs; Step 5: Post-experiment processing; Properly dispose of the experimental equipment after the demonstration.

2. The ion-trap confinement and quadrupole mass-spectrometry principle demonstration kit according to claim 1, characterized in that: The outer diameters of the middle sections of the first cap rod (10), the second cap rod (12), the radio frequency electrode (6), and the radio frequency electrode (11) are the same; insulating rings (7) are respectively provided between the radio frequency electrode (11) and the first cap rod (10) and the second cap rod (12), and between the first cap rod (10) and the radio frequency electrode (6).

3. The teaching aid for demonstrating the principles of ion trapping and quadrupole mass spectrometry according to claim 1, characterized in that: The top of the base (1) is fixedly installed with two symmetrically arranged first mounting seats (2) and two symmetrically arranged second mounting seats (8); the two second mounting seats (8) are located between the two first mounting seats (2); the two ends of the glass tube (5) pass through the two first mounting seats (2) respectively and are fixedly connected to the first mounting seats (2); the first cap rod (10) and the second cap rod (12) pass through one of the second mounting seats (8) respectively and are fixedly connected to the second mounting seat (8); a first buckle (3) is fixedly installed on the first mounting seat (2), and the first buckle (3) fixes the glass tube (5) on the first mounting seat (2).

4. The teaching aid for demonstrating the principles of ion trapping and quadrupole mass spectrometry according to claim 3, characterized in that: The second mounting base (8) is fixedly mounted with a second buckle (9) that is compatible with it and has the same structure; the second mounting base (8) and the second buckle (9) are respectively provided with mounting holes that are compatible with the segment rod, the segment rod passes through the mounting holes and is fixedly connected to the mounting holes; the top end of the second mounting base (8) and the bottom end of the second buckle (9) are provided with semi-circular through grooves that are compatible with the glass tube (5), and the two through grooves are correspondingly provided; the glass tube (5) passes through the through grooves and is fixedly connected to the through grooves; the side walls of the second mounting base (8) and the second buckle (9) are respectively threaded with a number of tightening bolts, and the tightening bolts abut against the segment rod.

5. The teaching aid for demonstrating the principles of ion trapping and quadrupole mass spectrometry according to claim 1, characterized in that: The sample particles (17) are made of metal and vary in size, with multiple sizes available.

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