Method for rapidly eliminating magnetic pole residual magnetic effect of rare gas magnetic deflection mass spectrometer

Abstract

The invention relates to the technical field of magnetic deflection mass spectrometer testing and analysis, in particular to a method for rapidly eliminating the residual magnetic effect of a magnetic pole of a rare gas magnetic deflection mass spectrometer. According to the method, the configuration parameters of the rare gas magnetic deflection mass spectrometer with the magnetic pole residual magnetic effect are adjusted to the configuration of rare gas elements with medium mass, and the magnetic pole residual magnetic effect of the rare gas magnetic deflection mass spectrometer is eliminated after staying for 20-60 minutes. After heavy elements are tested by the rare gas magnetic deflection mass spectrometer, the calibration peak value of helium is shifted, configuration parameters of the mass spectrometer stay on configuration parameters of rare gas elements with medium mass, the elimination time of residual magnetism of a magnetic pole is shortened from more than 12h to less than 1h, and the use efficiency of the magnetic deflection mass spectrometer is greatly improved. The residual magnetic field is eliminated by utilizing the property of the ferromagnetic pole, and the method is simple to operate and easy to master; the method can eliminate the influence of the residual magnetic field on a mass spectrometer analysis system in a short time, and improves the overall working efficiency.

Description

Technical Field

[0001] The invention relates to the technical field of mass spectrometer testing and analysis, and in particular to a method for rapidly eliminating magnetic pole residual magnetic effect of a rare gas magnetic deflection mass spectrometer. Background Art

[0002] The magnetic deflection mass spectrometer needs a strong magnetic field to deflect the atoms with larger mass when testing them. After the test, a residual magnetic field will be left on the magnetic pole piece of the mass spectrometer. This phenomenon is called the residual magnetic effect. The residual magnetic effect will cause the peak center of light-mass elements to shift, affecting the testing of light-mass elements in subsequent samples. The current element peak shift caused by the residual magnetic field has a great impact on the efficiency of the magnetic deflection mass spectrometer, and usually the residual magnetic field can only disappear on its own by waiting for a long time (more than 12 hours). The residual magnetic effect is an inherent physical property of ferromagnets. Traditional methods of removing the residual magnetism of ferromagnetic poles include knocking and heating, which cannot be used on expensive and precision-demanding rare gas magnetic deflection mass spectrometers. Therefore, it is very important to find a method that can quickly remove the residual magnetic effect of rare gas magnetic deflection mass spectrometers. Summary of the invention

[0003] The object of the present invention is to provide a method for rapidly eliminating the residual magnetic effect of the magnetic poles of a rare gas magnetic deflection mass spectrometer, so as to improve the use efficiency of the magnetic deflection mass spectrometer.

[0004] In order to achieve the above-mentioned object of the invention, the present invention provides the following technical solutions:

[0005] The invention provides a method for rapidly eliminating the magnetic pole remanent magnetic effect of a rare gas magnetic deflection mass spectrometer, comprising the following steps: adjusting the configuration parameters of the rare gas magnetic deflection mass spectrometer with the magnetic pole remanent magnetic effect to the configuration of a rare gas element with a medium mass, staying for 20 to 60 minutes, and completing the elimination of the magnetic pole remanent magnetic effect of the rare gas magnetic deflection mass spectrometer.

[0006] Optionally, the medium-mass rare gas element is neon or argon.

[0007] Optionally, the residence time is 25 to 40 minutes.

[0008] Optionally, the residence time is 30 minutes.

[0009] Optionally, the method further comprises: after the stop, rotating the screw rod on the magnetic pole piece so that 3 He and 4 The center of the He signal peak is consistent.

[0010] Compared with the prior art, the present invention has the following beneficial effects:

[0011] The present invention provides a method for rapidly eliminating the residual magnetism effect of the magnetic pole of a rare gas magnetic deflection mass spectrometer. After the rare gas magnetic deflection mass spectrometer tests heavy elements such as krypton and xenon, the calibration peak of the magnetic deflection mass spectrometer for helium is significantly offset, which will seriously affect the ratio and content test results of helium isotopes. By keeping the configuration parameters of the rare gas magnetic deflection mass spectrometer at the configuration parameters of the rare gas elements with medium mass, the elimination time of the residual magnetism on the magnetic pole is shortened from more than 12 hours to less than 1 hour, thereby greatly improving the use efficiency of the rare gas magnetic deflection mass spectrometer.

[0012] The method for quickly eliminating the residual magnetism of the magnetic poles of a rare gas magnetic deflection mass spectrometer provided by the present invention utilizes the properties of the ferromagnetic poles themselves to remove the magnetic field, and is simple to operate and easy to use; and the method can eliminate the influence of the residual magnetic field on the mass spectrometer analysis system in a short time, thereby improving the overall working efficiency of the test and analysis system; at the same time, the method avoids introducing traditional physical means such as impact and heating of the magnetic poles, thereby avoiding affecting the test accuracy and stability of the mass spectrometer. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a scan image of the Helix SFT mass spectrometer after He mass calibration in Example 1.

[0014] Figure 2 This is a scan image of He by the rare gas magnetic deflection mass spectrometer after testing the heavy element Xe in Example 1.

[0015] Figure 3 This is a mass consistency scan of He after reverse adjustment in Example 1.

[0016] Figure 4 This is a mass consistency scan of He after final adjustment in Example 1.

[0017] Figure 5 This is the mass consistency scan diagram of He after reverse adjustment in Example 2.

[0018] Figure 6 This is a mass consistency scan of He after final adjustment in Example 2.

[0019] Figure 7 This is a scan of the quality consistency of He after placement and adjustment in Comparative Example 1. DETAILED DESCRIPTION

[0020] Various exemplary embodiments of the present invention will now be described in detail. This detailed description should not be considered as limiting the present invention, but should be understood as a more detailed description of certain aspects, features, and embodiments of the present invention.

[0021] It should be understood that the terms described in the present invention are only for describing special embodiments and are not intended to limit the present invention. In addition, for the numerical range in the present invention, it should be understood that each intermediate value between the upper and lower limits of the scope is also specifically disclosed. Each smaller range between the intermediate value in any stated value or stated range and any other stated value or intermediate value in the described range is also included in the present invention. The upper and lower limits of these smaller ranges can be independently included or excluded in the scope.

[0022] Unless otherwise indicated, all technical and scientific terms used herein have the same meanings as those generally understood by those skilled in the art. Although the present invention describes only preferred methods and materials, any methods and materials similar or equivalent to those described herein may also be used in the implementation or testing of the present invention. All documents mentioned in this specification are incorporated by reference to disclose and describe the methods and / or materials associated with the documents. In the event of a conflict with any incorporated document, the content of this specification shall prevail.

[0023] It will be apparent to those skilled in the art that various modifications and variations may be made to the specific embodiments of the present invention description without departing from the scope or spirit of the present invention. Other embodiments derived from the present invention description will be apparent to those skilled in the art. The present application description and examples are exemplary only.

[0024] The words “include,” “including,” “have,” “contain,” etc. used in this document are open-ended terms, meaning including but not limited to.

[0025] The invention provides a method for rapidly eliminating the magnetic pole remanent magnetic effect of a rare gas magnetic deflection mass spectrometer, comprising the following steps: adjusting the configuration parameters of the rare gas magnetic deflection mass spectrometer with the magnetic pole remanent magnetic effect to the configuration of a rare gas element with a medium mass, staying for 20 to 60 minutes, and completing the elimination of the magnetic pole remanent magnetic effect of the rare gas magnetic deflection mass spectrometer.

[0026] The present invention has no limitation on the specific model of the magnetic deflection mass spectrometer. The method of the present invention is applicable to any model of a rare gas magnetic deflection mass spectrometer. In the embodiment, a rare gas mass spectrometer Helix SFT is used.

[0027] The present invention does not specifically limit the specific parameters of the configuration of the medium-quality rare gas element. Different rare gas magnetic deflection mass spectrometers have different optimal configuration parameters for testing different elements. Those skilled in the art can adjust the specific configuration parameters of each element according to the specific model of the rare gas magnetic deflection mass spectrometer used.

[0028] In some embodiments of the present invention, the medium-quality rare gas element is neon or argon, preferably argon. In the present invention, adjusting the configuration parameters of the rare gas magnetic deflection mass spectrometer to the configuration of neon or argon can accelerate the elimination of the residual magnetic effect. However, the inventors have found through experiments that when the configuration parameters are adjusted to the configuration of argon, the residual magnetic effect can be eliminated faster.

[0029] In the present invention, the residence time is 20 to 60 min, for example, 20 min, 25 min, 30 min, 35 min, 40 min, 45 min, 50 min, 55 min and 60 min, preferably 25-40 min, more preferably 30 min.

[0030] In some embodiments of the present invention, the method further comprises: after the dwelling is completed, rotating the screw rod on the magnetic pole piece so that 3 He and 4 In the present invention, after the dwell is completed, there is still a trace residual magnetic field in the rare gas magnetic deflection mass spectrometer, but it does not affect the test results. If the user wants to obtain more accurate test results, the screw on the magnetic pole piece can be slightly turned to make 3 He and 4 The center of the signal peak of He is consistent. The present invention does not specifically limit the rotation direction and amplitude of the screw rod. A person skilled in the art can configure the parameters of the medium-quality rare gas element for a certain period of time. 3 He, 4 He was mass calibrated according to 3 The center position of the He signal peak is relative to 4 The deviation of the center position of the He signal peak confirms the rotation direction and amplitude of the screw rod; for example 3 The center position of the He signal peak is relative to 4 If the center position of the He signal peak is to the left, the screw rod is rotated clockwise, otherwise the screw rod is rotated counterclockwise. In the embodiment of the present invention, 3 The center position of the He signal peak is relative to 4 The center position of the He signal peak shifts to the left (i.e., the direction of light mass), so rotating 1 / 4 turn clockwise makes 3 He and 4 The center of the He signal peak is consistent.

[0031] The magnetic deflection mass spectrometer with residual magnetic effect used in the embodiment of the present invention is obtained by the following steps:

[0032] The laboratory was kept at a constant temperature of 20°C and a constant humidity of 40%. The following steps were performed using a magnetic deflection mass spectrometer Helix SFT:

[0033] The first step is to inject an appropriate amount of atmospheric standard samples into the pre-processing system to purify and separate the noble gases, and then inject the separated helium (He) into the magnetic deflection mass spectrometer to 3 He, 4 He was used for mass calibration and mass scanning (results were as follows Figure 1 As shown in the figure, 3 He (red left peak), 4 The center positions of the signal peaks of He (blue peak) are aligned, indicating good consistency.

[0034] In the second step, the configuration parameters of the magnetic deflection mass spectrometer are adjusted to the xenon (Xe) configuration. After staying for 10 minutes, the magnetic field configuration of the mass spectrometer is changed to a strong magnetic field. When the configuration parameters are switched to He, residual magnetism is left on the magnetic pole pieces of the magnetic deflection mass spectrometer, resulting in a magnetic deflection mass spectrometer with residual magnetism effect.

[0035] In order to verify whether the above method produces residual magnetic effect, the configuration parameters of the magnetic deflection mass spectrometer with residual magnetic effect are readjusted to the configuration parameters of He, and the mass scan of He is performed (the results are shown in Figure 2 ). Figure 2 It can be seen 3 The center of the He signal peak has drifted significantly toward lower mass, indicating that the above method has produced a residual magnetic effect.

[0036] Example 1

[0037] The configuration parameters of the rare gas magnetic deflection mass spectrometer with residual magnetic effect obtained by the above method are adjusted to the configuration parameters of argon and kept for 30 minutes to reversely adjust the magnetic poles of the magnetic deflection mass spectrometer.

[0038] Inject He into the magnetic deflection mass spectrometer, switch the magnetic deflection mass spectrometer configuration parameters to the He configuration parameters, and 3 He, 4 He performed a mass consistency scan, and the results were as follows Figure 3 As shown. Figure 3 It can be seen that after the argon configuration parameters are reversed, Figure 1 and Figure 2 In comparison, 3 The center position of the He signal peak shows an obvious regression, but there is still a slight offset, but the degree of offset meets the requirements of routine testing.

[0039] After turning the screw on the pole piece clockwise 1 / 4 turn, 3 He, 4 He performed a mass consistency scan, and the results were as follows Figure 4 As shown. Figure 4 It can be seen that 3 He and 4The center positions of the He signal peaks are aligned, indicating that the residual magnetic effect is eliminated.

[0040] Example 2

[0041] The configuration parameters of the magnetic deflection mass spectrometer with residual magnetic effect obtained by the above method are adjusted to the neon configuration, and the configuration is kept for 30 minutes, and the magnetic poles of the magnetic deflection mass spectrometer are reversely adjusted.

[0042] Inject He into the magnetic deflection mass spectrometer, switch the magnetic deflection mass spectrometer configuration parameters to the He configuration parameters, and 3 He, 4 He performed a mass consistency scan, and the results were as follows Figure 5 As shown. Figure 5 It can be seen that after the Ar configuration reverse adjustment, Figure 1 and Figure 2 In comparison, 3 The center position of the He signal peak shows an obvious regression, but it can be seen that the effect of adjusting the configuration parameters compared to the use of argon is 3 The regression effect at the center of the He signal peak is slightly worse.

[0043] After turning the screw on the pole piece clockwise 1 / 4 turn, 3 He, 4 He performed a mass consistency scan, and the results were as follows Figure 6 As shown. Figure 6 It can be seen that 3 He and 4 The center positions of the He signal peaks are aligned, indicating that the residual magnetic effect is eliminated.

[0044] Comparative Example 1

[0045] After the magnetic deflection mass spectrometer with residual magnetic effect was placed for 12h and 14h respectively, the configuration parameters of the magnetic deflection mass spectrometer were readjusted to the He configuration and mass scanning of He was performed. Figure 7 As shown, after 14 hours, 3 The degree to which the center position of the He signal peak deviates toward the light mass direction is still large, indicating that natural placement cannot completely eliminate the residual magnetic effect.

[0046] As can be seen from the above embodiments, the present invention takes the rare gas mass spectrometer Helix SFT as an example. The mass spectrometer can test five elements: helium, neon, argon, krypton, and xenon. 3 He, 4 After mass correction, the center of the He signal peak has good consistency. After testing the heavy isotope, due to the influence of the magnetic pole residual magnetic effect, the mass spectrometer 3The He calibration peak shifts toward the light mass direction. By keeping the mass spectrometer configuration parameters at the configuration parameters of the medium-mass noble gas, 3 The center position of the He signal peak showed an obvious regression, which shortened the removal time of the mass spectrometer residual magnetism from 12 hours to less than 1 hour, greatly improving the utilization efficiency of the mass spectrometer.

[0047] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principle of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A method for rapidly eliminating the residual magnetic effect of the magnetic poles of a rare gas magnetic deflection mass spectrometer, comprising the following steps: The configuration parameters of the rare gas magnetic deflection mass spectrometer with magnetic pole remanent magnetic effect are adjusted to the configuration of the rare gas element with medium mass, and the configuration is kept for 20 to 60 minutes to complete the elimination of the magnetic pole remanent magnetic effect of the rare gas magnetic deflection mass spectrometer.

2. The method according to claim 1, characterized in that The medium-mass rare gas element is neon or argon.

3. The method according to claim 1 or 2, characterized in that: The residence time is 25 to 40 minutes.

4. The method according to claim 3, characterized in that: The residence time is 30 min.

5. The method according to claim 1 or 2, characterized in that: The method further comprises: after the stop, rotating the screw rod on the magnetic pole piece so that 3 He and 4 The center of the He signal peak is consistent.

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